ExprConstant.cpp source code [clang_source_code/lib/AST/ExprConstant.cpp]

1	//===--- ExprConstant.cpp - Expression Constant Evaluator -----------------===//
2	//
3	// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4	// See https://llvm.org/LICENSE.txt for license information.
5	// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6	//
7	//===----------------------------------------------------------------------===//
8	//
9	// This file implements the Expr constant evaluator.
10	//
11	// Constant expression evaluation produces four main results:
12	//
13	// * A success/failure flag indicating whether constant folding was successful.
14	// This is the 'bool' return value used by most of the code in this file. A
15	// 'false' return value indicates that constant folding has failed, and any
16	// appropriate diagnostic has already been produced.
17	//
18	// * An evaluated result, valid only if constant folding has not failed.
19	//
20	// * A flag indicating if evaluation encountered (unevaluated) side-effects.
21	// These arise in cases such as (sideEffect(), 0) and (sideEffect() \|\| 1),
22	// where it is possible to determine the evaluated result regardless.
23	//
24	// * A set of notes indicating why the evaluation was not a constant expression
25	// (under the C++11 / C++1y rules only, at the moment), or, if folding failed
26	// too, why the expression could not be folded.
27	//
28	// If we are checking for a potential constant expression, failure to constant
29	// fold a potential constant sub-expression will be indicated by a 'false'
30	// return value (the expression could not be folded) and no diagnostic (the
31	// expression is not necessarily non-constant).
32	//
33	//===----------------------------------------------------------------------===//
34
35	#include "clang/AST/APValue.h"
36	#include "clang/AST/ASTContext.h"
37	#include "clang/AST/ASTDiagnostic.h"
38	#include "clang/AST/ASTLambda.h"
39	#include "clang/AST/CharUnits.h"
40	#include "clang/AST/Expr.h"
41	#include "clang/AST/OSLog.h"
42	#include "clang/AST/RecordLayout.h"
43	#include "clang/AST/StmtVisitor.h"
44	#include "clang/AST/TypeLoc.h"
45	#include "clang/Basic/Builtins.h"
46	#include "clang/Basic/FixedPoint.h"
47	#include "clang/Basic/TargetInfo.h"
48	#include "llvm/Support/SaveAndRestore.h"
49	#include "llvm/Support/raw_ostream.h"
50	#include <cstring>
51	#include <functional>
52
53	#define DEBUG_TYPE "exprconstant"
54
55	using namespace clang;
56	using llvm::APSInt;
57	using llvm::APFloat;
58
59	static bool IsGlobalLValue(APValue::LValueBase B);
60
61	namespace {
62	struct LValue;
63	struct CallStackFrame;
64	struct EvalInfo;
65
66	static QualType getType(APValue::LValueBase B) {
67	if (!B) return QualType();
68	if (const ValueDecl D = B.dyn_cast<const ValueDecl>()) {
69	// FIXME: It's unclear where we're supposed to take the type from, and
70	// this actually matters for arrays of unknown bound. Eg:
71	//
72	// extern int arr[]; void f() { extern int arr[3]; };
73	// constexpr int *p = &arr[1]; // valid?
74	//
75	// For now, we take the array bound from the most recent declaration.
76	for (auto *Redecl = cast<ValueDecl>(D->getMostRecentDecl()); Redecl;
77	Redecl = cast_or_null<ValueDecl>(Redecl->getPreviousDecl())) {
78	QualType T = Redecl->getType();
79	if (!T->isIncompleteArrayType())
80	return T;
81	}
82	return D->getType();
83	}
84
85	const Expr Base = B.get<const Expr>();
86
87	// For a materialized temporary, the type of the temporary we materialized
88	// may not be the type of the expression.
89	if (const MaterializeTemporaryExpr *MTE =
90	dyn_cast<MaterializeTemporaryExpr>(Base)) {
91	SmallVector<const Expr *, 2> CommaLHSs;
92	SmallVector<SubobjectAdjustment, 2> Adjustments;
93	const Expr *Temp = MTE->GetTemporaryExpr();
94	const Expr *Inner = Temp->skipRValueSubobjectAdjustments(CommaLHSs,
95	Adjustments);
96	// Keep any cv-qualifiers from the reference if we generated a temporary
97	// for it directly. Otherwise use the type after adjustment.
98	if (!Adjustments.empty())
99	return Inner->getType();
100	}
101
102	return Base->getType();
103	}
104
105	/// Get an LValue path entry, which is known to not be an array index, as a
106	/// field or base class.
107	static
108	APValue::BaseOrMemberType getAsBaseOrMember(APValue::LValuePathEntry E) {
109	APValue::BaseOrMemberType Value;
110	Value.setFromOpaqueValue(E.BaseOrMember);
111	return Value;
112	}
113
114	/// Get an LValue path entry, which is known to not be an array index, as a
115	/// field declaration.
116	static const FieldDecl *getAsField(APValue::LValuePathEntry E) {
117	return dyn_cast<FieldDecl>(getAsBaseOrMember(E).getPointer());
118	}
119	/// Get an LValue path entry, which is known to not be an array index, as a
120	/// base class declaration.
121	static const CXXRecordDecl *getAsBaseClass(APValue::LValuePathEntry E) {
122	return dyn_cast<CXXRecordDecl>(getAsBaseOrMember(E).getPointer());
123	}
124	/// Determine whether this LValue path entry for a base class names a virtual
125	/// base class.
126	static bool isVirtualBaseClass(APValue::LValuePathEntry E) {
127	return getAsBaseOrMember(E).getInt();
128	}
129
130	/// Given a CallExpr, try to get the alloc_size attribute. May return null.
131	static const AllocSizeAttr getAllocSizeAttr(const CallExpr CE) {
132	const FunctionDecl *Callee = CE->getDirectCallee();
133	return Callee ? Callee->getAttr<AllocSizeAttr>() : nullptr;
134	}
135
136	/// Attempts to unwrap a CallExpr (with an alloc_size attribute) from an Expr.
137	/// This will look through a single cast.
138	///
139	/// Returns null if we couldn't unwrap a function with alloc_size.
140	static const CallExpr tryUnwrapAllocSizeCall(const Expr E) {
141	if (!E->getType()->isPointerType())
142	return nullptr;
143
144	E = E->IgnoreParens();
145	// If we're doing a variable assignment from e.g. malloc(N), there will
146	// probably be a cast of some kind. In exotic cases, we might also see a
147	// top-level ExprWithCleanups. Ignore them either way.
148	if (const auto *FE = dyn_cast<FullExpr>(E))
149	E = FE->getSubExpr()->IgnoreParens();
150
151	if (const auto *Cast = dyn_cast<CastExpr>(E))
152	E = Cast->getSubExpr()->IgnoreParens();
153
154	if (const auto *CE = dyn_cast<CallExpr>(E))
155	return getAllocSizeAttr(CE) ? CE : nullptr;
156	return nullptr;
157	}
158
159	/// Determines whether or not the given Base contains a call to a function
160	/// with the alloc_size attribute.
161	static bool isBaseAnAllocSizeCall(APValue::LValueBase Base) {
162	const auto E = Base.dyn_cast<const Expr >();
163	return E && E->getType()->isPointerType() && tryUnwrapAllocSizeCall(E);
164	}
165
166	/// The bound to claim that an array of unknown bound has.
167	/// The value in MostDerivedArraySize is undefined in this case. So, set it
168	/// to an arbitrary value that's likely to loudly break things if it's used.
169	static const uint64_t AssumedSizeForUnsizedArray =
170	std::numeric_limits<uint64_t>::max() / 2;
171
172	/// Determines if an LValue with the given LValueBase will have an unsized
173	/// array in its designator.
174	/// Find the path length and type of the most-derived subobject in the given
175	/// path, and find the size of the containing array, if any.
176	static unsigned
177	findMostDerivedSubobject(ASTContext &Ctx, APValue::LValueBase Base,
178	ArrayRef<APValue::LValuePathEntry> Path,
179	uint64_t &ArraySize, QualType &Type, bool &IsArray,
180	bool &FirstEntryIsUnsizedArray) {
181	// This only accepts LValueBases from APValues, and APValues don't support
182	// arrays that lack size info.
183	(0) . __assert_fail ("!isBaseAnAllocSizeCall(Base) && \"Unsized arrays shouldn't appear here\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 184, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(!isBaseAnAllocSizeCall(Base) &&
184	(0) . __assert_fail ("!isBaseAnAllocSizeCall(Base) && \"Unsized arrays shouldn't appear here\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 184, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true"> "Unsized arrays shouldn't appear here");
185	unsigned MostDerivedLength = 0;
186	Type = getType(Base);
187
188	for (unsigned I = 0, N = Path.size(); I != N; ++I) {
189	if (Type->isArrayType()) {
190	const ArrayType *AT = Ctx.getAsArrayType(Type);
191	Type = AT->getElementType();
192	MostDerivedLength = I + 1;
193	IsArray = true;
194
195	if (auto *CAT = dyn_cast<ConstantArrayType>(AT)) {
196	ArraySize = CAT->getSize().getZExtValue();
197	} else {
198	(0) . __assert_fail ("I == 0 && \"unexpected unsized array designator\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 198, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(I == 0 && "unexpected unsized array designator");
199	FirstEntryIsUnsizedArray = true;
200	ArraySize = AssumedSizeForUnsizedArray;
201	}
202	} else if (Type->isAnyComplexType()) {
203	const ComplexType *CT = Type->castAs<ComplexType>();
204	Type = CT->getElementType();
205	ArraySize = 2;
206	MostDerivedLength = I + 1;
207	IsArray = true;
208	} else if (const FieldDecl *FD = getAsField(Path[I])) {
209	Type = FD->getType();
210	ArraySize = 0;
211	MostDerivedLength = I + 1;
212	IsArray = false;
213	} else {
214	// Path[I] describes a base class.
215	ArraySize = 0;
216	IsArray = false;
217	}
218	}
219	return MostDerivedLength;
220	}
221
222	// The order of this enum is important for diagnostics.
223	enum CheckSubobjectKind {
224	CSK_Base, CSK_Derived, CSK_Field, CSK_ArrayToPointer, CSK_ArrayIndex,
225	CSK_This, CSK_Real, CSK_Imag
226	};
227
228	/// A path from a glvalue to a subobject of that glvalue.
229	struct SubobjectDesignator {
230	/// True if the subobject was named in a manner not supported by C++11. Such
231	/// lvalues can still be folded, but they are not core constant expressions
232	/// and we cannot perform lvalue-to-rvalue conversions on them.
233	unsigned Invalid : 1;
234
235	/// Is this a pointer one past the end of an object?
236	unsigned IsOnePastTheEnd : 1;
237
238	/// Indicator of whether the first entry is an unsized array.
239	unsigned FirstEntryIsAnUnsizedArray : 1;
240
241	/// Indicator of whether the most-derived object is an array element.
242	unsigned MostDerivedIsArrayElement : 1;
243
244	/// The length of the path to the most-derived object of which this is a
245	/// subobject.
246	unsigned MostDerivedPathLength : 28;
247
248	/// The size of the array of which the most-derived object is an element.
249	/// This will always be 0 if the most-derived object is not an array
250	/// element. 0 is not an indicator of whether or not the most-derived object
251	/// is an array, however, because 0-length arrays are allowed.
252	///
253	/// If the current array is an unsized array, the value of this is
254	/// undefined.
255	uint64_t MostDerivedArraySize;
256
257	/// The type of the most derived object referred to by this address.
258	QualType MostDerivedType;
259
260	typedef APValue::LValuePathEntry PathEntry;
261
262	/// The entries on the path from the glvalue to the designated subobject.
263	SmallVector<PathEntry, 8> Entries;
264
265	SubobjectDesignator() : Invalid(true) {}
266
267	explicit SubobjectDesignator(QualType T)
268	: Invalid(false), IsOnePastTheEnd(false),
269	FirstEntryIsAnUnsizedArray(false), MostDerivedIsArrayElement(false),
270	MostDerivedPathLength(0), MostDerivedArraySize(0),
271	MostDerivedType(T) {}
272
273	SubobjectDesignator(ASTContext &Ctx, const APValue &V)
274	: Invalid(!V.isLValue() \|\| !V.hasLValuePath()), IsOnePastTheEnd(false),
275	FirstEntryIsAnUnsizedArray(false), MostDerivedIsArrayElement(false),
276	MostDerivedPathLength(0), MostDerivedArraySize(0) {
277	(0) . __assert_fail ("V.isLValue() && \"Non-LValue used to make an LValue designator?\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 277, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(V.isLValue() && "Non-LValue used to make an LValue designator?");
278	if (!Invalid) {
279	IsOnePastTheEnd = V.isLValueOnePastTheEnd();
280	ArrayRef<PathEntry> VEntries = V.getLValuePath();
281	Entries.insert(Entries.end(), VEntries.begin(), VEntries.end());
282	if (V.getLValueBase()) {
283	bool IsArray = false;
284	bool FirstIsUnsizedArray = false;
285	MostDerivedPathLength = findMostDerivedSubobject(
286	Ctx, V.getLValueBase(), V.getLValuePath(), MostDerivedArraySize,
287	MostDerivedType, IsArray, FirstIsUnsizedArray);
288	MostDerivedIsArrayElement = IsArray;
289	FirstEntryIsAnUnsizedArray = FirstIsUnsizedArray;
290	}
291	}
292	}
293
294	void setInvalid() {
295	Invalid = true;
296	Entries.clear();
297	}
298
299	/// Determine whether the most derived subobject is an array without a
300	/// known bound.
301	bool isMostDerivedAnUnsizedArray() const {
302	(0) . __assert_fail ("!Invalid && \"Calling this makes no sense on invalid designators\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 302, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(!Invalid && "Calling this makes no sense on invalid designators");
303	return Entries.size() == 1 && FirstEntryIsAnUnsizedArray;
304	}
305
306	/// Determine what the most derived array's size is. Results in an assertion
307	/// failure if the most derived array lacks a size.
308	uint64_t getMostDerivedArraySize() const {
309	(0) . __assert_fail ("!isMostDerivedAnUnsizedArray() && \"Unsized array has no size\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 309, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(!isMostDerivedAnUnsizedArray() && "Unsized array has no size");
310	return MostDerivedArraySize;
311	}
312
313	/// Determine whether this is a one-past-the-end pointer.
314	bool isOnePastTheEnd() const {
315	assert(!Invalid);
316	if (IsOnePastTheEnd)
317	return true;
318	if (!isMostDerivedAnUnsizedArray() && MostDerivedIsArrayElement &&
319	Entries[MostDerivedPathLength - 1].ArrayIndex == MostDerivedArraySize)
320	return true;
321	return false;
322	}
323
324	/// Get the range of valid index adjustments in the form
325	/// {maximum value that can be subtracted from this pointer,
326	/// maximum value that can be added to this pointer}
327	std::pair<uint64_t, uint64_t> validIndexAdjustments() {
328	if (Invalid \|\| isMostDerivedAnUnsizedArray())
329	return {0, 0};
330
331	// [expr.add]p4: For the purposes of these operators, a pointer to a
332	// nonarray object behaves the same as a pointer to the first element of
333	// an array of length one with the type of the object as its element type.
334	bool IsArray = MostDerivedPathLength == Entries.size() &&
335	MostDerivedIsArrayElement;
336	uint64_t ArrayIndex =
337	IsArray ? Entries.back().ArrayIndex : (uint64_t)IsOnePastTheEnd;
338	uint64_t ArraySize =
339	IsArray ? getMostDerivedArraySize() : (uint64_t)1;
340	return {ArrayIndex, ArraySize - ArrayIndex};
341	}
342
343	/// Check that this refers to a valid subobject.
344	bool isValidSubobject() const {
345	if (Invalid)
346	return false;
347	return !isOnePastTheEnd();
348	}
349	/// Check that this refers to a valid subobject, and if not, produce a
350	/// relevant diagnostic and set the designator as invalid.
351	bool checkSubobject(EvalInfo &Info, const Expr *E, CheckSubobjectKind CSK);
352
353	/// Get the type of the designated object.
354	QualType getType(ASTContext &Ctx) const {
355	(0) . __assert_fail ("!Invalid && \"invalid designator has no subobject type\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 355, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(!Invalid && "invalid designator has no subobject type");
356	return MostDerivedPathLength == Entries.size()
357	? MostDerivedType
358	: Ctx.getRecordType(getAsBaseClass(Entries.back()));
359	}
360
361	/// Update this designator to refer to the first element within this array.
362	void addArrayUnchecked(const ConstantArrayType *CAT) {
363	PathEntry Entry;
364	Entry.ArrayIndex = 0;
365	Entries.push_back(Entry);
366
367	// This is a most-derived object.
368	MostDerivedType = CAT->getElementType();
369	MostDerivedIsArrayElement = true;
370	MostDerivedArraySize = CAT->getSize().getZExtValue();
371	MostDerivedPathLength = Entries.size();
372	}
373	/// Update this designator to refer to the first element within the array of
374	/// elements of type T. This is an array of unknown size.
375	void addUnsizedArrayUnchecked(QualType ElemTy) {
376	PathEntry Entry;
377	Entry.ArrayIndex = 0;
378	Entries.push_back(Entry);
379
380	MostDerivedType = ElemTy;
381	MostDerivedIsArrayElement = true;
382	// The value in MostDerivedArraySize is undefined in this case. So, set it
383	// to an arbitrary value that's likely to loudly break things if it's
384	// used.
385	MostDerivedArraySize = AssumedSizeForUnsizedArray;
386	MostDerivedPathLength = Entries.size();
387	}
388	/// Update this designator to refer to the given base or member of this
389	/// object.
390	void addDeclUnchecked(const Decl *D, bool Virtual = false) {
391	PathEntry Entry;
392	APValue::BaseOrMemberType Value(D, Virtual);
393	Entry.BaseOrMember = Value.getOpaqueValue();
394	Entries.push_back(Entry);
395
396	// If this isn't a base class, it's a new most-derived object.
397	if (const FieldDecl *FD = dyn_cast<FieldDecl>(D)) {
398	MostDerivedType = FD->getType();
399	MostDerivedIsArrayElement = false;
400	MostDerivedArraySize = 0;
401	MostDerivedPathLength = Entries.size();
402	}
403	}
404	/// Update this designator to refer to the given complex component.
405	void addComplexUnchecked(QualType EltTy, bool Imag) {
406	PathEntry Entry;
407	Entry.ArrayIndex = Imag;
408	Entries.push_back(Entry);
409
410	// This is technically a most-derived object, though in practice this
411	// is unlikely to matter.
412	MostDerivedType = EltTy;
413	MostDerivedIsArrayElement = true;
414	MostDerivedArraySize = 2;
415	MostDerivedPathLength = Entries.size();
416	}
417	void diagnoseUnsizedArrayPointerArithmetic(EvalInfo &Info, const Expr *E);
418	void diagnosePointerArithmetic(EvalInfo &Info, const Expr *E,
419	const APSInt &N);
420	/// Add N to the address of this subobject.
421	void adjustIndex(EvalInfo &Info, const Expr *E, APSInt N) {
422	if (Invalid \|\| !N) return;
423	uint64_t TruncatedN = N.extOrTrunc(64).getZExtValue();
424	if (isMostDerivedAnUnsizedArray()) {
425	diagnoseUnsizedArrayPointerArithmetic(Info, E);
426	// Can't verify -- trust that the user is doing the right thing (or if
427	// not, trust that the caller will catch the bad behavior).
428	// FIXME: Should we reject if this overflows, at least?
429	Entries.back().ArrayIndex += TruncatedN;
430	return;
431	}
432
433	// [expr.add]p4: For the purposes of these operators, a pointer to a
434	// nonarray object behaves the same as a pointer to the first element of
435	// an array of length one with the type of the object as its element type.
436	bool IsArray = MostDerivedPathLength == Entries.size() &&
437	MostDerivedIsArrayElement;
438	uint64_t ArrayIndex =
439	IsArray ? Entries.back().ArrayIndex : (uint64_t)IsOnePastTheEnd;
440	uint64_t ArraySize =
441	IsArray ? getMostDerivedArraySize() : (uint64_t)1;
442
443	if (N < -(int64_t)ArrayIndex \|\| N > ArraySize - ArrayIndex) {
444	// Calculate the actual index in a wide enough type, so we can include
445	// it in the note.
446	N = N.extend(std::max<unsigned>(N.getBitWidth() + 1, 65));
447	(llvm::APInt&)N += ArrayIndex;
448	(0) . __assert_fail ("N.ugt(ArraySize) && \"bounds check failed for in-bounds index\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 448, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(N.ugt(ArraySize) && "bounds check failed for in-bounds index");
449	diagnosePointerArithmetic(Info, E, N);
450	setInvalid();
451	return;
452	}
453
454	ArrayIndex += TruncatedN;
455	(0) . __assert_fail ("ArrayIndex <= ArraySize && \"bounds check succeeded for out-of-bounds index\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 456, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(ArrayIndex <= ArraySize &&
456	(0) . __assert_fail ("ArrayIndex <= ArraySize && \"bounds check succeeded for out-of-bounds index\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 456, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true"> "bounds check succeeded for out-of-bounds index");
457
458	if (IsArray)
459	Entries.back().ArrayIndex = ArrayIndex;
460	else
461	IsOnePastTheEnd = (ArrayIndex != 0);
462	}
463	};
464
465	/// A stack frame in the constexpr call stack.
466	struct CallStackFrame {
467	EvalInfo &Info;
468
469	/// Parent - The caller of this stack frame.
470	CallStackFrame *Caller;
471
472	/// Callee - The function which was called.
473	const FunctionDecl *Callee;
474
475	/// This - The binding for the this pointer in this call, if any.
476	const LValue *This;
477
478	/// Arguments - Parameter bindings for this function call, indexed by
479	/// parameters' function scope indices.
480	APValue *Arguments;
481
482	// Note that we intentionally use std::map here so that references to
483	// values are stable.
484	typedef std::pair<const void *, unsigned> MapKeyTy;
485	typedef std::map<MapKeyTy, APValue> MapTy;
486	/// Temporaries - Temporary lvalues materialized within this stack frame.
487	MapTy Temporaries;
488
489	/// CallLoc - The location of the call expression for this call.
490	SourceLocation CallLoc;
491
492	/// Index - The call index of this call.
493	unsigned Index;
494
495	/// The stack of integers for tracking version numbers for temporaries.
496	SmallVector<unsigned, 2> TempVersionStack = {1};
497	unsigned CurTempVersion = TempVersionStack.back();
498
499	unsigned getTempVersion() const { return TempVersionStack.back(); }
500
501	void pushTempVersion() {
502	TempVersionStack.push_back(++CurTempVersion);
503	}
504
505	void popTempVersion() {
506	TempVersionStack.pop_back();
507	}
508
509	// FIXME: Adding this to every 'CallStackFrame' may have a nontrivial impact
510	// on the overall stack usage of deeply-recursing constexpr evaluations.
511	// (We should cache this map rather than recomputing it repeatedly.)
512	// But let's try this and see how it goes; we can look into caching the map
513	// as a later change.
514
515	/// LambdaCaptureFields - Mapping from captured variables/this to
516	/// corresponding data members in the closure class.
517	llvm::DenseMap<const VarDecl , FieldDecl > LambdaCaptureFields;
518	FieldDecl *LambdaThisCaptureField;
519
520	CallStackFrame(EvalInfo &Info, SourceLocation CallLoc,
521	const FunctionDecl Callee, const LValue This,
522	APValue *Arguments);
523	~CallStackFrame();
524
525	// Return the temporary for Key whose version number is Version.
526	APValue getTemporary(const void Key, unsigned Version) {
527	MapKeyTy KV(Key, Version);
528	auto LB = Temporaries.lower_bound(KV);
529	if (LB != Temporaries.end() && LB->first == KV)
530	return &LB->second;
531	// Pair (Key,Version) wasn't found in the map. Check that no elements
532	// in the map have 'Key' as their key.
533	(0) . __assert_fail ("(LB == Temporaries.end() \|\| LB->first.first != Key) && (LB == Temporaries.begin() \|\| std..prev(LB)->first.first != Key) && \"Element with key 'Key' found in map\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 535, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert((LB == Temporaries.end() \|\| LB->first.first != Key) &&
534	(0) . __assert_fail ("(LB == Temporaries.end() \|\| LB->first.first != Key) && (LB == Temporaries.begin() \|\| std..prev(LB)->first.first != Key) && \"Element with key 'Key' found in map\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 535, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true"> (LB == Temporaries.begin() \|\| std::prev(LB)->first.first != Key) &&
535	(0) . __assert_fail ("(LB == Temporaries.end() \|\| LB->first.first != Key) && (LB == Temporaries.begin() \|\| std..prev(LB)->first.first != Key) && \"Element with key 'Key' found in map\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 535, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true"> "Element with key 'Key' found in map");
536	return nullptr;
537	}
538
539	// Return the current temporary for Key in the map.
540	APValue getCurrentTemporary(const void Key) {
541	auto UB = Temporaries.upper_bound(MapKeyTy(Key, UINT_MAX));
542	if (UB != Temporaries.begin() && std::prev(UB)->first.first == Key)
543	return &std::prev(UB)->second;
544	return nullptr;
545	}
546
547	// Return the version number of the current temporary for Key.
548	unsigned getCurrentTemporaryVersion(const void *Key) const {
549	auto UB = Temporaries.upper_bound(MapKeyTy(Key, UINT_MAX));
550	if (UB != Temporaries.begin() && std::prev(UB)->first.first == Key)
551	return std::prev(UB)->first.second;
552	return 0;
553	}
554
555	APValue &createTemporary(const void *Key, bool IsLifetimeExtended);
556	};
557
558	/// Temporarily override 'this'.
559	class ThisOverrideRAII {
560	public:
561	ThisOverrideRAII(CallStackFrame &Frame, const LValue *NewThis, bool Enable)
562	: Frame(Frame), OldThis(Frame.This) {
563	if (Enable)
564	Frame.This = NewThis;
565	}
566	~ThisOverrideRAII() {
567	Frame.This = OldThis;
568	}
569	private:
570	CallStackFrame &Frame;
571	const LValue *OldThis;
572	};
573
574	/// A partial diagnostic which we might know in advance that we are not going
575	/// to emit.
576	class OptionalDiagnostic {
577	PartialDiagnostic *Diag;
578
579	public:
580	explicit OptionalDiagnostic(PartialDiagnostic *Diag = nullptr)
581	: Diag(Diag) {}
582
583	template<typename T>
584	OptionalDiagnostic &operator<<(const T &v) {
585	if (Diag)
586	*Diag << v;
587	return *this;
588	}
589
590	OptionalDiagnostic &operator<<(const APSInt &I) {
591	if (Diag) {
592	SmallVector<char, 32> Buffer;
593	I.toString(Buffer);
594	*Diag << StringRef(Buffer.data(), Buffer.size());
595	}
596	return *this;
597	}
598
599	OptionalDiagnostic &operator<<(const APFloat &F) {
600	if (Diag) {
601	// FIXME: Force the precision of the source value down so we don't
602	// print digits which are usually useless (we don't really care here if
603	// we truncate a digit by accident in edge cases). Ideally,
604	// APFloat::toString would automatically print the shortest
605	// representation which rounds to the correct value, but it's a bit
606	// tricky to implement.
607	unsigned precision =
608	llvm::APFloat::semanticsPrecision(F.getSemantics());
609	precision = (precision * 59 + 195) / 196;
610	SmallVector<char, 32> Buffer;
611	F.toString(Buffer, precision);
612	*Diag << StringRef(Buffer.data(), Buffer.size());
613	}
614	return *this;
615	}
616
617	OptionalDiagnostic &operator<<(const APFixedPoint &FX) {
618	if (Diag) {
619	SmallVector<char, 32> Buffer;
620	FX.toString(Buffer);
621	*Diag << StringRef(Buffer.data(), Buffer.size());
622	}
623	return *this;
624	}
625	};
626
627	/// A cleanup, and a flag indicating whether it is lifetime-extended.
628	class Cleanup {
629	llvm::PointerIntPair<APValue*, 1, bool> Value;
630
631	public:
632	Cleanup(APValue *Val, bool IsLifetimeExtended)
633	: Value(Val, IsLifetimeExtended) {}
634
635	bool isLifetimeExtended() const { return Value.getInt(); }
636	void endLifetime() {
637	*Value.getPointer() = APValue();
638	}
639	};
640
641	/// EvalInfo - This is a private struct used by the evaluator to capture
642	/// information about a subexpression as it is folded. It retains information
643	/// about the AST context, but also maintains information about the folded
644	/// expression.
645	///
646	/// If an expression could be evaluated, it is still possible it is not a C
647	/// "integer constant expression" or constant expression. If not, this struct
648	/// captures information about how and why not.
649	///
650	/// One bit of information passed into the request for constant folding
651	/// indicates whether the subexpression is "evaluated" or not according to C
652	/// rules. For example, the RHS of (0 && foo()) is not evaluated. We can
653	/// evaluate the expression regardless of what the RHS is, but C only allows
654	/// certain things in certain situations.
655	struct EvalInfo {
656	ASTContext &Ctx;
657
658	/// EvalStatus - Contains information about the evaluation.
659	Expr::EvalStatus &EvalStatus;
660
661	/// CurrentCall - The top of the constexpr call stack.
662	CallStackFrame *CurrentCall;
663
664	/// CallStackDepth - The number of calls in the call stack right now.
665	unsigned CallStackDepth;
666
667	/// NextCallIndex - The next call index to assign.
668	unsigned NextCallIndex;
669
670	/// StepsLeft - The remaining number of evaluation steps we're permitted
671	/// to perform. This is essentially a limit for the number of statements
672	/// we will evaluate.
673	unsigned StepsLeft;
674
675	/// BottomFrame - The frame in which evaluation started. This must be
676	/// initialized after CurrentCall and CallStackDepth.
677	CallStackFrame BottomFrame;
678
679	/// A stack of values whose lifetimes end at the end of some surrounding
680	/// evaluation frame.
681	llvm::SmallVector<Cleanup, 16> CleanupStack;
682
683	/// EvaluatingDecl - This is the declaration whose initializer is being
684	/// evaluated, if any.
685	APValue::LValueBase EvaluatingDecl;
686
687	/// EvaluatingDeclValue - This is the value being constructed for the
688	/// declaration whose initializer is being evaluated, if any.
689	APValue *EvaluatingDeclValue;
690
691	/// EvaluatingObject - Pair of the AST node that an lvalue represents and
692	/// the call index that that lvalue was allocated in.
693	typedef std::pair<APValue::LValueBase, std::pair<unsigned, unsigned>>
694	EvaluatingObject;
695
696	/// EvaluatingConstructors - Set of objects that are currently being
697	/// constructed.
698	llvm::DenseSet<EvaluatingObject> EvaluatingConstructors;
699
700	struct EvaluatingConstructorRAII {
701	EvalInfo &EI;
702	EvaluatingObject Object;
703	bool DidInsert;
704	EvaluatingConstructorRAII(EvalInfo &EI, EvaluatingObject Object)
705	: EI(EI), Object(Object) {
706	DidInsert = EI.EvaluatingConstructors.insert(Object).second;
707	}
708	~EvaluatingConstructorRAII() {
709	if (DidInsert) EI.EvaluatingConstructors.erase(Object);
710	}
711	};
712
713	bool isEvaluatingConstructor(APValue::LValueBase Decl, unsigned CallIndex,
714	unsigned Version) {
715	return EvaluatingConstructors.count(
716	EvaluatingObject(Decl, {CallIndex, Version}));
717	}
718
719	/// The current array initialization index, if we're performing array
720	/// initialization.
721	uint64_t ArrayInitIndex = -1;
722
723	/// HasActiveDiagnostic - Was the previous diagnostic stored? If so, further
724	/// notes attached to it will also be stored, otherwise they will not be.
725	bool HasActiveDiagnostic;
726
727	/// Have we emitted a diagnostic explaining why we couldn't constant
728	/// fold (not just why it's not strictly a constant expression)?
729	bool HasFoldFailureDiagnostic;
730
731	/// Whether or not we're currently speculatively evaluating.
732	bool IsSpeculativelyEvaluating;
733
734	/// Whether or not we're in a context where the front end requires a
735	/// constant value.
736	bool InConstantContext;
737
738	enum EvaluationMode {
739	/// Evaluate as a constant expression. Stop if we find that the expression
740	/// is not a constant expression.
741	EM_ConstantExpression,
742
743	/// Evaluate as a potential constant expression. Keep going if we hit a
744	/// construct that we can't evaluate yet (because we don't yet know the
745	/// value of something) but stop if we hit something that could never be
746	/// a constant expression.
747	EM_PotentialConstantExpression,
748
749	/// Fold the expression to a constant. Stop if we hit a side-effect that
750	/// we can't model.
751	EM_ConstantFold,
752
753	/// Evaluate the expression looking for integer overflow and similar
754	/// issues. Don't worry about side-effects, and try to visit all
755	/// subexpressions.
756	EM_EvaluateForOverflow,
757
758	/// Evaluate in any way we know how. Don't worry about side-effects that
759	/// can't be modeled.
760	EM_IgnoreSideEffects,
761
762	/// Evaluate as a constant expression. Stop if we find that the expression
763	/// is not a constant expression. Some expressions can be retried in the
764	/// optimizer if we don't constant fold them here, but in an unevaluated
765	/// context we try to fold them immediately since the optimizer never
766	/// gets a chance to look at it.
767	EM_ConstantExpressionUnevaluated,
768
769	/// Evaluate as a potential constant expression. Keep going if we hit a
770	/// construct that we can't evaluate yet (because we don't yet know the
771	/// value of something) but stop if we hit something that could never be
772	/// a constant expression. Some expressions can be retried in the
773	/// optimizer if we don't constant fold them here, but in an unevaluated
774	/// context we try to fold them immediately since the optimizer never
775	/// gets a chance to look at it.
776	EM_PotentialConstantExpressionUnevaluated,
777	} EvalMode;
778
779	/// Are we checking whether the expression is a potential constant
780	/// expression?
781	bool checkingPotentialConstantExpression() const {
782	return EvalMode == EM_PotentialConstantExpression \|\|
783	EvalMode == EM_PotentialConstantExpressionUnevaluated;
784	}
785
786	/// Are we checking an expression for overflow?
787	// FIXME: We should check for any kind of undefined or suspicious behavior
788	// in such constructs, not just overflow.
789	bool checkingForOverflow() { return EvalMode == EM_EvaluateForOverflow; }
790
791	EvalInfo(const ASTContext &C, Expr::EvalStatus &S, EvaluationMode Mode)
792	: Ctx(const_cast<ASTContext &>(C)), EvalStatus(S), CurrentCall(nullptr),
793	CallStackDepth(0), NextCallIndex(1),
794	StepsLeft(getLangOpts().ConstexprStepLimit),
795	BottomFrame(*this, SourceLocation(), nullptr, nullptr, nullptr),
796	EvaluatingDecl((const ValueDecl *)nullptr),
797	EvaluatingDeclValue(nullptr), HasActiveDiagnostic(false),
798	HasFoldFailureDiagnostic(false), IsSpeculativelyEvaluating(false),
799	InConstantContext(false), EvalMode(Mode) {}
800
801	void setEvaluatingDecl(APValue::LValueBase Base, APValue &Value) {
802	EvaluatingDecl = Base;
803	EvaluatingDeclValue = &Value;
804	EvaluatingConstructors.insert({Base, {0, 0}});
805	}
806
807	const LangOptions &getLangOpts() const { return Ctx.getLangOpts(); }
808
809	bool CheckCallLimit(SourceLocation Loc) {
810	// Don't perform any constexpr calls (other than the call we're checking)
811	// when checking a potential constant expression.
812	if (checkingPotentialConstantExpression() && CallStackDepth > 1)
813	return false;
814	if (NextCallIndex == 0) {
815	// NextCallIndex has wrapped around.
816	FFDiag(Loc, diag::note_constexpr_call_limit_exceeded);
817	return false;
818	}
819	if (CallStackDepth <= getLangOpts().ConstexprCallDepth)
820	return true;
821	FFDiag(Loc, diag::note_constexpr_depth_limit_exceeded)
822	<< getLangOpts().ConstexprCallDepth;
823	return false;
824	}
825
826	CallStackFrame *getCallFrame(unsigned CallIndex) {
827	(0) . __assert_fail ("CallIndex && \"no call index in getCallFrame\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 827, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(CallIndex && "no call index in getCallFrame");
828	// We will eventually hit BottomFrame, which has Index 1, so Frame can't
829	// be null in this loop.
830	CallStackFrame *Frame = CurrentCall;
831	while (Frame->Index > CallIndex)
832	Frame = Frame->Caller;
833	return (Frame->Index == CallIndex) ? Frame : nullptr;
834	}
835
836	bool nextStep(const Stmt *S) {
837	if (!StepsLeft) {
838	FFDiag(S->getBeginLoc(), diag::note_constexpr_step_limit_exceeded);
839	return false;
840	}
841	--StepsLeft;
842	return true;
843	}
844
845	private:
846	/// Add a diagnostic to the diagnostics list.
847	PartialDiagnostic &addDiag(SourceLocation Loc, diag::kind DiagId) {
848	PartialDiagnostic PD(DiagId, Ctx.getDiagAllocator());
849	EvalStatus.Diag->push_back(std::make_pair(Loc, PD));
850	return EvalStatus.Diag->back().second;
851	}
852
853	/// Add notes containing a call stack to the current point of evaluation.
854	void addCallStack(unsigned Limit);
855
856	private:
857	OptionalDiagnostic Diag(SourceLocation Loc, diag::kind DiagId,
858	unsigned ExtraNotes, bool IsCCEDiag) {
859
860	if (EvalStatus.Diag) {
861	// If we have a prior diagnostic, it will be noting that the expression
862	// isn't a constant expression. This diagnostic is more important,
863	// unless we require this evaluation to produce a constant expression.
864	//
865	// FIXME: We might want to show both diagnostics to the user in
866	// EM_ConstantFold mode.
867	if (!EvalStatus.Diag->empty()) {
868	switch (EvalMode) {
869	case EM_ConstantFold:
870	case EM_IgnoreSideEffects:
871	case EM_EvaluateForOverflow:
872	if (!HasFoldFailureDiagnostic)
873	break;
874	// We've already failed to fold something. Keep that diagnostic.
875	LLVM_FALLTHROUGH;
876	case EM_ConstantExpression:
877	case EM_PotentialConstantExpression:
878	case EM_ConstantExpressionUnevaluated:
879	case EM_PotentialConstantExpressionUnevaluated:
880	HasActiveDiagnostic = false;
881	return OptionalDiagnostic();
882	}
883	}
884
885	unsigned CallStackNotes = CallStackDepth - 1;
886	unsigned Limit = Ctx.getDiagnostics().getConstexprBacktraceLimit();
887	if (Limit)
888	CallStackNotes = std::min(CallStackNotes, Limit + 1);
889	if (checkingPotentialConstantExpression())
890	CallStackNotes = 0;
891
892	HasActiveDiagnostic = true;
893	HasFoldFailureDiagnostic = !IsCCEDiag;
894	EvalStatus.Diag->clear();
895	EvalStatus.Diag->reserve(1 + ExtraNotes + CallStackNotes);
896	addDiag(Loc, DiagId);
897	if (!checkingPotentialConstantExpression())
898	addCallStack(Limit);
899	return OptionalDiagnostic(&(*EvalStatus.Diag)[0].second);
900	}
901	HasActiveDiagnostic = false;
902	return OptionalDiagnostic();
903	}
904	public:
905	// Diagnose that the evaluation could not be folded (FF => FoldFailure)
906	OptionalDiagnostic
907	FFDiag(SourceLocation Loc,
908	diag::kind DiagId = diag::note_invalid_subexpr_in_const_expr,
909	unsigned ExtraNotes = 0) {
910	return Diag(Loc, DiagId, ExtraNotes, false);
911	}
912
913	OptionalDiagnostic FFDiag(const Expr *E, diag::kind DiagId
914	= diag::note_invalid_subexpr_in_const_expr,
915	unsigned ExtraNotes = 0) {
916	if (EvalStatus.Diag)
917	return Diag(E->getExprLoc(), DiagId, ExtraNotes, /IsCCEDiag/false);
918	HasActiveDiagnostic = false;
919	return OptionalDiagnostic();
920	}
921
922	/// Diagnose that the evaluation does not produce a C++11 core constant
923	/// expression.
924	///
925	/// FIXME: Stop evaluating if we're in EM_ConstantExpression or
926	/// EM_PotentialConstantExpression mode and we produce one of these.
927	OptionalDiagnostic CCEDiag(SourceLocation Loc, diag::kind DiagId
928	= diag::note_invalid_subexpr_in_const_expr,
929	unsigned ExtraNotes = 0) {
930	// Don't override a previous diagnostic. Don't bother collecting
931	// diagnostics if we're evaluating for overflow.
932	if (!EvalStatus.Diag \|\| !EvalStatus.Diag->empty()) {
933	HasActiveDiagnostic = false;
934	return OptionalDiagnostic();
935	}
936	return Diag(Loc, DiagId, ExtraNotes, true);
937	}
938	OptionalDiagnostic CCEDiag(const Expr *E, diag::kind DiagId
939	= diag::note_invalid_subexpr_in_const_expr,
940	unsigned ExtraNotes = 0) {
941	return CCEDiag(E->getExprLoc(), DiagId, ExtraNotes);
942	}
943	/// Add a note to a prior diagnostic.
944	OptionalDiagnostic Note(SourceLocation Loc, diag::kind DiagId) {
945	if (!HasActiveDiagnostic)
946	return OptionalDiagnostic();
947	return OptionalDiagnostic(&addDiag(Loc, DiagId));
948	}
949
950	/// Add a stack of notes to a prior diagnostic.
951	void addNotes(ArrayRef<PartialDiagnosticAt> Diags) {
952	if (HasActiveDiagnostic) {
953	EvalStatus.Diag->insert(EvalStatus.Diag->end(),
954	Diags.begin(), Diags.end());
955	}
956	}
957
958	/// Should we continue evaluation after encountering a side-effect that we
959	/// couldn't model?
960	bool keepEvaluatingAfterSideEffect() {
961	switch (EvalMode) {
962	case EM_PotentialConstantExpression:
963	case EM_PotentialConstantExpressionUnevaluated:
964	case EM_EvaluateForOverflow:
965	case EM_IgnoreSideEffects:
966	return true;
967
968	case EM_ConstantExpression:
969	case EM_ConstantExpressionUnevaluated:
970	case EM_ConstantFold:
971	return false;
972	}
973	llvm_unreachable("Missed EvalMode case");
974	}
975
976	/// Note that we have had a side-effect, and determine whether we should
977	/// keep evaluating.
978	bool noteSideEffect() {
979	EvalStatus.HasSideEffects = true;
980	return keepEvaluatingAfterSideEffect();
981	}
982
983	/// Should we continue evaluation after encountering undefined behavior?
984	bool keepEvaluatingAfterUndefinedBehavior() {
985	switch (EvalMode) {
986	case EM_EvaluateForOverflow:
987	case EM_IgnoreSideEffects:
988	case EM_ConstantFold:
989	return true;
990
991	case EM_PotentialConstantExpression:
992	case EM_PotentialConstantExpressionUnevaluated:
993	case EM_ConstantExpression:
994	case EM_ConstantExpressionUnevaluated:
995	return false;
996	}
997	llvm_unreachable("Missed EvalMode case");
998	}
999
1000	/// Note that we hit something that was technically undefined behavior, but
1001	/// that we can evaluate past it (such as signed overflow or floating-point
1002	/// division by zero.)
1003	bool noteUndefinedBehavior() {
1004	EvalStatus.HasUndefinedBehavior = true;
1005	return keepEvaluatingAfterUndefinedBehavior();
1006	}
1007
1008	/// Should we continue evaluation as much as possible after encountering a
1009	/// construct which can't be reduced to a value?
1010	bool keepEvaluatingAfterFailure() {
1011	if (!StepsLeft)
1012	return false;
1013
1014	switch (EvalMode) {
1015	case EM_PotentialConstantExpression:
1016	case EM_PotentialConstantExpressionUnevaluated:
1017	case EM_EvaluateForOverflow:
1018	return true;
1019
1020	case EM_ConstantExpression:
1021	case EM_ConstantExpressionUnevaluated:
1022	case EM_ConstantFold:
1023	case EM_IgnoreSideEffects:
1024	return false;
1025	}
1026	llvm_unreachable("Missed EvalMode case");
1027	}
1028
1029	/// Notes that we failed to evaluate an expression that other expressions
1030	/// directly depend on, and determine if we should keep evaluating. This
1031	/// should only be called if we actually intend to keep evaluating.
1032	///
1033	/// Call noteSideEffect() instead if we may be able to ignore the value that
1034	/// we failed to evaluate, e.g. if we failed to evaluate Foo() in:
1035	///
1036	/// (Foo(), 1) // use noteSideEffect
1037	/// (Foo() \|\| true) // use noteSideEffect
1038	/// Foo() + 1 // use noteFailure
1039	LLVM_NODISCARD bool noteFailure() {
1040	// Failure when evaluating some expression often means there is some
1041	// subexpression whose evaluation was skipped. Therefore, (because we
1042	// don't track whether we skipped an expression when unwinding after an
1043	// evaluation failure) every evaluation failure that bubbles up from a
1044	// subexpression implies that a side-effect has potentially happened. We
1045	// skip setting the HasSideEffects flag to true until we decide to
1046	// continue evaluating after that point, which happens here.
1047	bool KeepGoing = keepEvaluatingAfterFailure();
1048	EvalStatus.HasSideEffects \|= KeepGoing;
1049	return KeepGoing;
1050	}
1051
1052	class ArrayInitLoopIndex {
1053	EvalInfo &Info;
1054	uint64_t OuterIndex;
1055
1056	public:
1057	ArrayInitLoopIndex(EvalInfo &Info)
1058	: Info(Info), OuterIndex(Info.ArrayInitIndex) {
1059	Info.ArrayInitIndex = 0;
1060	}
1061	~ArrayInitLoopIndex() { Info.ArrayInitIndex = OuterIndex; }
1062
1063	operator uint64_t&() { return Info.ArrayInitIndex; }
1064	};
1065	};
1066
1067	/// Object used to treat all foldable expressions as constant expressions.
1068	struct FoldConstant {
1069	EvalInfo &Info;
1070	bool Enabled;
1071	bool HadNoPriorDiags;
1072	EvalInfo::EvaluationMode OldMode;
1073
1074	explicit FoldConstant(EvalInfo &Info, bool Enabled)
1075	: Info(Info),
1076	Enabled(Enabled),
1077	HadNoPriorDiags(Info.EvalStatus.Diag &&
1078	Info.EvalStatus.Diag->empty() &&
1079	!Info.EvalStatus.HasSideEffects),
1080	OldMode(Info.EvalMode) {
1081	if (Enabled &&
1082	(Info.EvalMode == EvalInfo::EM_ConstantExpression \|\|
1083	Info.EvalMode == EvalInfo::EM_ConstantExpressionUnevaluated))
1084	Info.EvalMode = EvalInfo::EM_ConstantFold;
1085	}
1086	void keepDiagnostics() { Enabled = false; }
1087	~FoldConstant() {
1088	if (Enabled && HadNoPriorDiags && !Info.EvalStatus.Diag->empty() &&
1089	!Info.EvalStatus.HasSideEffects)
1090	Info.EvalStatus.Diag->clear();
1091	Info.EvalMode = OldMode;
1092	}
1093	};
1094
1095	/// RAII object used to set the current evaluation mode to ignore
1096	/// side-effects.
1097	struct IgnoreSideEffectsRAII {
1098	EvalInfo &Info;
1099	EvalInfo::EvaluationMode OldMode;
1100	explicit IgnoreSideEffectsRAII(EvalInfo &Info)
1101	: Info(Info), OldMode(Info.EvalMode) {
1102	if (!Info.checkingPotentialConstantExpression())
1103	Info.EvalMode = EvalInfo::EM_IgnoreSideEffects;
1104	}
1105
1106	~IgnoreSideEffectsRAII() { Info.EvalMode = OldMode; }
1107	};
1108
1109	/// RAII object used to optionally suppress diagnostics and side-effects from
1110	/// a speculative evaluation.
1111	class SpeculativeEvaluationRAII {
1112	EvalInfo *Info = nullptr;
1113	Expr::EvalStatus OldStatus;
1114	bool OldIsSpeculativelyEvaluating;
1115
1116	void moveFromAndCancel(SpeculativeEvaluationRAII &&Other) {
1117	Info = Other.Info;
1118	OldStatus = Other.OldStatus;
1119	OldIsSpeculativelyEvaluating = Other.OldIsSpeculativelyEvaluating;
1120	Other.Info = nullptr;
1121	}
1122
1123	void maybeRestoreState() {
1124	if (!Info)
1125	return;
1126
1127	Info->EvalStatus = OldStatus;
1128	Info->IsSpeculativelyEvaluating = OldIsSpeculativelyEvaluating;
1129	}
1130
1131	public:
1132	SpeculativeEvaluationRAII() = default;
1133
1134	SpeculativeEvaluationRAII(
1135	EvalInfo &Info, SmallVectorImpl<PartialDiagnosticAt> *NewDiag = nullptr)
1136	: Info(&Info), OldStatus(Info.EvalStatus),
1137	OldIsSpeculativelyEvaluating(Info.IsSpeculativelyEvaluating) {
1138	Info.EvalStatus.Diag = NewDiag;
1139	Info.IsSpeculativelyEvaluating = true;
1140	}
1141
1142	SpeculativeEvaluationRAII(const SpeculativeEvaluationRAII &Other) = delete;
1143	SpeculativeEvaluationRAII(SpeculativeEvaluationRAII &&Other) {
1144	moveFromAndCancel(std::move(Other));
1145	}
1146
1147	SpeculativeEvaluationRAII &operator=(SpeculativeEvaluationRAII &&Other) {
1148	maybeRestoreState();
1149	moveFromAndCancel(std::move(Other));
1150	return *this;
1151	}
1152
1153	~SpeculativeEvaluationRAII() { maybeRestoreState(); }
1154	};
1155
1156	/// RAII object wrapping a full-expression or block scope, and handling
1157	/// the ending of the lifetime of temporaries created within it.
1158	template<bool IsFullExpression>
1159	class ScopeRAII {
1160	EvalInfo &Info;
1161	unsigned OldStackSize;
1162	public:
1163	ScopeRAII(EvalInfo &Info)
1164	: Info(Info), OldStackSize(Info.CleanupStack.size()) {
1165	// Push a new temporary version. This is needed to distinguish between
1166	// temporaries created in different iterations of a loop.
1167	Info.CurrentCall->pushTempVersion();
1168	}
1169	~ScopeRAII() {
1170	// Body moved to a static method to encourage the compiler to inline away
1171	// instances of this class.
1172	cleanup(Info, OldStackSize);
1173	Info.CurrentCall->popTempVersion();
1174	}
1175	private:
1176	static void cleanup(EvalInfo &Info, unsigned OldStackSize) {
1177	unsigned NewEnd = OldStackSize;
1178	for (unsigned I = OldStackSize, N = Info.CleanupStack.size();
1179	I != N; ++I) {
1180	if (IsFullExpression && Info.CleanupStack[I].isLifetimeExtended()) {
1181	// Full-expression cleanup of a lifetime-extended temporary: nothing
1182	// to do, just move this cleanup to the right place in the stack.
1183	std::swap(Info.CleanupStack[I], Info.CleanupStack[NewEnd]);
1184	++NewEnd;
1185	} else {
1186	// End the lifetime of the object.
1187	Info.CleanupStack[I].endLifetime();
1188	}
1189	}
1190	Info.CleanupStack.erase(Info.CleanupStack.begin() + NewEnd,
1191	Info.CleanupStack.end());
1192	}
1193	};
1194	typedef ScopeRAII<false> BlockScopeRAII;
1195	typedef ScopeRAII<true> FullExpressionRAII;
1196	}
1197
1198	bool SubobjectDesignator::checkSubobject(EvalInfo &Info, const Expr *E,
1199	CheckSubobjectKind CSK) {
1200	if (Invalid)
1201	return false;
1202	if (isOnePastTheEnd()) {
1203	Info.CCEDiag(E, diag::note_constexpr_past_end_subobject)
1204	<< CSK;
1205	setInvalid();
1206	return false;
1207	}
1208	// Note, we do not diagnose if isMostDerivedAnUnsizedArray(), because there
1209	// must actually be at least one array element; even a VLA cannot have a
1210	// bound of zero. And if our index is nonzero, we already had a CCEDiag.
1211	return true;
1212	}
1213
1214	void SubobjectDesignator::diagnoseUnsizedArrayPointerArithmetic(EvalInfo &Info,
1215	const Expr *E) {
1216	Info.CCEDiag(E, diag::note_constexpr_unsized_array_indexed);
1217	// Do not set the designator as invalid: we can represent this situation,
1218	// and correct handling of __builtin_object_size requires us to do so.
1219	}
1220
1221	void SubobjectDesignator::diagnosePointerArithmetic(EvalInfo &Info,
1222	const Expr *E,
1223	const APSInt &N) {
1224	// If we're complaining, we must be able to statically determine the size of
1225	// the most derived array.
1226	if (MostDerivedPathLength == Entries.size() && MostDerivedIsArrayElement)
1227	Info.CCEDiag(E, diag::note_constexpr_array_index)
1228	<< N << /array/ 0
1229	<< static_cast<unsigned>(getMostDerivedArraySize());
1230	else
1231	Info.CCEDiag(E, diag::note_constexpr_array_index)
1232	<< N << /non-array/ 1;
1233	setInvalid();
1234	}
1235
1236	CallStackFrame::CallStackFrame(EvalInfo &Info, SourceLocation CallLoc,
1237	const FunctionDecl Callee, const LValue This,
1238	APValue *Arguments)
1239	: Info(Info), Caller(Info.CurrentCall), Callee(Callee), This(This),
1240	Arguments(Arguments), CallLoc(CallLoc), Index(Info.NextCallIndex++) {
1241	Info.CurrentCall = this;
1242	++Info.CallStackDepth;
1243	}
1244
1245	CallStackFrame::~CallStackFrame() {
1246	(0) . __assert_fail ("Info.CurrentCall == this && \"calls retired out of order\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 1246, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(Info.CurrentCall == this && "calls retired out of order");
1247	--Info.CallStackDepth;
1248	Info.CurrentCall = Caller;
1249	}
1250
1251	APValue &CallStackFrame::createTemporary(const void *Key,
1252	bool IsLifetimeExtended) {
1253	unsigned Version = Info.CurrentCall->getTempVersion();
1254	APValue &Result = Temporaries[MapKeyTy(Key, Version)];
1255	(0) . __assert_fail ("Result.isUninit() && \"temporary created multiple times\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 1255, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(Result.isUninit() && "temporary created multiple times");
1256	Info.CleanupStack.push_back(Cleanup(&Result, IsLifetimeExtended));
1257	return Result;
1258	}
1259
1260	static void describeCall(CallStackFrame *Frame, raw_ostream &Out);
1261
1262	void EvalInfo::addCallStack(unsigned Limit) {
1263	// Determine which calls to skip, if any.
1264	unsigned ActiveCalls = CallStackDepth - 1;
1265	unsigned SkipStart = ActiveCalls, SkipEnd = SkipStart;
1266	if (Limit && Limit < ActiveCalls) {
1267	SkipStart = Limit / 2 + Limit % 2;
1268	SkipEnd = ActiveCalls - Limit / 2;
1269	}
1270
1271	// Walk the call stack and add the diagnostics.
1272	unsigned CallIdx = 0;
1273	for (CallStackFrame *Frame = CurrentCall; Frame != &BottomFrame;
1274	Frame = Frame->Caller, ++CallIdx) {
1275	// Skip this call?
1276	if (CallIdx >= SkipStart && CallIdx < SkipEnd) {
1277	if (CallIdx == SkipStart) {
1278	// Note that we're skipping calls.
1279	addDiag(Frame->CallLoc, diag::note_constexpr_calls_suppressed)
1280	<< unsigned(ActiveCalls - Limit);
1281	}
1282	continue;
1283	}
1284
1285	// Use a different note for an inheriting constructor, because from the
1286	// user's perspective it's not really a function at all.
1287	if (auto *CD = dyn_cast_or_null<CXXConstructorDecl>(Frame->Callee)) {
1288	if (CD->isInheritingConstructor()) {
1289	addDiag(Frame->CallLoc, diag::note_constexpr_inherited_ctor_call_here)
1290	<< CD->getParent();
1291	continue;
1292	}
1293	}
1294
1295	SmallVector<char, 128> Buffer;
1296	llvm::raw_svector_ostream Out(Buffer);
1297	describeCall(Frame, Out);
1298	addDiag(Frame->CallLoc, diag::note_constexpr_call_here) << Out.str();
1299	}
1300	}
1301
1302	/// Kinds of access we can perform on an object, for diagnostics.
1303	enum AccessKinds {
1304	AK_Read,
1305	AK_Assign,
1306	AK_Increment,
1307	AK_Decrement
1308	};
1309
1310	namespace {
1311	struct ComplexValue {
1312	private:
1313	bool IsInt;
1314
1315	public:
1316	APSInt IntReal, IntImag;
1317	APFloat FloatReal, FloatImag;
1318
1319	ComplexValue() : FloatReal(APFloat::Bogus()), FloatImag(APFloat::Bogus()) {}
1320
1321	void makeComplexFloat() { IsInt = false; }
1322	bool isComplexFloat() const { return !IsInt; }
1323	APFloat &getComplexFloatReal() { return FloatReal; }
1324	APFloat &getComplexFloatImag() { return FloatImag; }
1325
1326	void makeComplexInt() { IsInt = true; }
1327	bool isComplexInt() const { return IsInt; }
1328	APSInt &getComplexIntReal() { return IntReal; }
1329	APSInt &getComplexIntImag() { return IntImag; }
1330
1331	void moveInto(APValue &v) const {
1332	if (isComplexFloat())
1333	v = APValue(FloatReal, FloatImag);
1334	else
1335	v = APValue(IntReal, IntImag);
1336	}
1337	void setFrom(const APValue &v) {
1338	assert(v.isComplexFloat() \|\| v.isComplexInt());
1339	if (v.isComplexFloat()) {
1340	makeComplexFloat();
1341	FloatReal = v.getComplexFloatReal();
1342	FloatImag = v.getComplexFloatImag();
1343	} else {
1344	makeComplexInt();
1345	IntReal = v.getComplexIntReal();
1346	IntImag = v.getComplexIntImag();
1347	}
1348	}
1349	};
1350
1351	struct LValue {
1352	APValue::LValueBase Base;
1353	CharUnits Offset;
1354	SubobjectDesignator Designator;
1355	bool IsNullPtr : 1;
1356	bool InvalidBase : 1;
1357
1358	const APValue::LValueBase getLValueBase() const { return Base; }
1359	CharUnits &getLValueOffset() { return Offset; }
1360	const CharUnits &getLValueOffset() const { return Offset; }
1361	SubobjectDesignator &getLValueDesignator() { return Designator; }
1362	const SubobjectDesignator &getLValueDesignator() const { return Designator;}
1363	bool isNullPointer() const { return IsNullPtr;}
1364
1365	unsigned getLValueCallIndex() const { return Base.getCallIndex(); }
1366	unsigned getLValueVersion() const { return Base.getVersion(); }
1367
1368	void moveInto(APValue &V) const {
1369	if (Designator.Invalid)
1370	V = APValue(Base, Offset, APValue::NoLValuePath(), IsNullPtr);
1371	else {
1372	(0) . __assert_fail ("!InvalidBase && \"APValues can't handle invalid LValue bases\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 1372, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(!InvalidBase && "APValues can't handle invalid LValue bases");
1373	V = APValue(Base, Offset, Designator.Entries,
1374	Designator.IsOnePastTheEnd, IsNullPtr);
1375	}
1376	}
1377	void setFrom(ASTContext &Ctx, const APValue &V) {
1378	(0) . __assert_fail ("V.isLValue() && \"Setting LValue from a non-LValue?\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 1378, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(V.isLValue() && "Setting LValue from a non-LValue?");
1379	Base = V.getLValueBase();
1380	Offset = V.getLValueOffset();
1381	InvalidBase = false;
1382	Designator = SubobjectDesignator(Ctx, V);
1383	IsNullPtr = V.isNullPointer();
1384	}
1385
1386	void set(APValue::LValueBase B, bool BInvalid = false) {
1387	#ifndef NDEBUG
1388	// We only allow a few types of invalid bases. Enforce that here.
1389	if (BInvalid) {
1390	const auto E = B.get<const Expr >();
1391	(0) . __assert_fail ("(isa(E) \|\| tryUnwrapAllocSizeCall(E)) && \"Unexpected type of invalid base\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 1392, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert((isa<MemberExpr>(E) \|\| tryUnwrapAllocSizeCall(E)) &&
1392	(0) . __assert_fail ("(isa(E) \|\| tryUnwrapAllocSizeCall(E)) && \"Unexpected type of invalid base\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 1392, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true"> "Unexpected type of invalid base");
1393	}
1394	#endif
1395
1396	Base = B;
1397	Offset = CharUnits::fromQuantity(0);
1398	InvalidBase = BInvalid;
1399	Designator = SubobjectDesignator(getType(B));
1400	IsNullPtr = false;
1401	}
1402
1403	void setNull(QualType PointerTy, uint64_t TargetVal) {
1404	Base = (Expr *)nullptr;
1405	Offset = CharUnits::fromQuantity(TargetVal);
1406	InvalidBase = false;
1407	Designator = SubobjectDesignator(PointerTy->getPointeeType());
1408	IsNullPtr = true;
1409	}
1410
1411	void setInvalid(APValue::LValueBase B, unsigned I = 0) {
1412	set(B, true);
1413	}
1414
1415	private:
1416	// Check that this LValue is not based on a null pointer. If it is, produce
1417	// a diagnostic and mark the designator as invalid.
1418	template <typename GenDiagType>
1419	bool checkNullPointerDiagnosingWith(const GenDiagType &GenDiag) {
1420	if (Designator.Invalid)
1421	return false;
1422	if (IsNullPtr) {
1423	GenDiag();
1424	Designator.setInvalid();
1425	return false;
1426	}
1427	return true;
1428	}
1429
1430	public:
1431	bool checkNullPointer(EvalInfo &Info, const Expr *E,
1432	CheckSubobjectKind CSK) {
1433	return checkNullPointerDiagnosingWith([&Info, E, CSK] {
1434	Info.CCEDiag(E, diag::note_constexpr_null_subobject) << CSK;
1435	});
1436	}
1437
1438	bool checkNullPointerForFoldAccess(EvalInfo &Info, const Expr *E,
1439	AccessKinds AK) {
1440	return checkNullPointerDiagnosingWith([&Info, E, AK] {
1441	Info.FFDiag(E, diag::note_constexpr_access_null) << AK;
1442	});
1443	}
1444
1445	// Check this LValue refers to an object. If not, set the designator to be
1446	// invalid and emit a diagnostic.
1447	bool checkSubobject(EvalInfo &Info, const Expr *E, CheckSubobjectKind CSK) {
1448	return (CSK == CSK_ArrayToPointer \|\| checkNullPointer(Info, E, CSK)) &&
1449	Designator.checkSubobject(Info, E, CSK);
1450	}
1451
1452	void addDecl(EvalInfo &Info, const Expr *E,
1453	const Decl *D, bool Virtual = false) {
1454	if (checkSubobject(Info, E, isa<FieldDecl>(D) ? CSK_Field : CSK_Base))
1455	Designator.addDeclUnchecked(D, Virtual);
1456	}
1457	void addUnsizedArray(EvalInfo &Info, const Expr *E, QualType ElemTy) {
1458	if (!Designator.Entries.empty()) {
1459	Info.CCEDiag(E, diag::note_constexpr_unsupported_unsized_array);
1460	Designator.setInvalid();
1461	return;
1462	}
1463	if (checkSubobject(Info, E, CSK_ArrayToPointer)) {
1464	isPointerType() \|\| getType(Base)->isArrayType()", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 1464, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(getType(Base)->isPointerType() \|\| getType(Base)->isArrayType());
1465	Designator.FirstEntryIsAnUnsizedArray = true;
1466	Designator.addUnsizedArrayUnchecked(ElemTy);
1467	}
1468	}
1469	void addArray(EvalInfo &Info, const Expr E, const ConstantArrayType CAT) {
1470	if (checkSubobject(Info, E, CSK_ArrayToPointer))
1471	Designator.addArrayUnchecked(CAT);
1472	}
1473	void addComplex(EvalInfo &Info, const Expr *E, QualType EltTy, bool Imag) {
1474	if (checkSubobject(Info, E, Imag ? CSK_Imag : CSK_Real))
1475	Designator.addComplexUnchecked(EltTy, Imag);
1476	}
1477	void clearIsNullPointer() {
1478	IsNullPtr = false;
1479	}
1480	void adjustOffsetAndIndex(EvalInfo &Info, const Expr *E,
1481	const APSInt &Index, CharUnits ElementSize) {
1482	// An index of 0 has no effect. (In C, adding 0 to a null pointer is UB,
1483	// but we're not required to diagnose it and it's valid in C++.)
1484	if (!Index)
1485	return;
1486
1487	// Compute the new offset in the appropriate width, wrapping at 64 bits.
1488	// FIXME: When compiling for a 32-bit target, we should use 32-bit
1489	// offsets.
1490	uint64_t Offset64 = Offset.getQuantity();
1491	uint64_t ElemSize64 = ElementSize.getQuantity();
1492	uint64_t Index64 = Index.extOrTrunc(64).getZExtValue();
1493	Offset = CharUnits::fromQuantity(Offset64 + ElemSize64 * Index64);
1494
1495	if (checkNullPointer(Info, E, CSK_ArrayIndex))
1496	Designator.adjustIndex(Info, E, Index);
1497	clearIsNullPointer();
1498	}
1499	void adjustOffset(CharUnits N) {
1500	Offset += N;
1501	if (N.getQuantity())
1502	clearIsNullPointer();
1503	}
1504	};
1505
1506	struct MemberPtr {
1507	MemberPtr() {}
1508	explicit MemberPtr(const ValueDecl *Decl) :
1509	DeclAndIsDerivedMember(Decl, false), Path() {}
1510
1511	/// The member or (direct or indirect) field referred to by this member
1512	/// pointer, or 0 if this is a null member pointer.
1513	const ValueDecl *getDecl() const {
1514	return DeclAndIsDerivedMember.getPointer();
1515	}
1516	/// Is this actually a member of some type derived from the relevant class?
1517	bool isDerivedMember() const {
1518	return DeclAndIsDerivedMember.getInt();
1519	}
1520	/// Get the class which the declaration actually lives in.
1521	const CXXRecordDecl *getContainingRecord() const {
1522	return cast<CXXRecordDecl>(
1523	DeclAndIsDerivedMember.getPointer()->getDeclContext());
1524	}
1525
1526	void moveInto(APValue &V) const {
1527	V = APValue(getDecl(), isDerivedMember(), Path);
1528	}
1529	void setFrom(const APValue &V) {
1530	assert(V.isMemberPointer());
1531	DeclAndIsDerivedMember.setPointer(V.getMemberPointerDecl());
1532	DeclAndIsDerivedMember.setInt(V.isMemberPointerToDerivedMember());
1533	Path.clear();
1534	ArrayRef<const CXXRecordDecl*> P = V.getMemberPointerPath();
1535	Path.insert(Path.end(), P.begin(), P.end());
1536	}
1537
1538	/// DeclAndIsDerivedMember - The member declaration, and a flag indicating
1539	/// whether the member is a member of some class derived from the class type
1540	/// of the member pointer.
1541	llvm::PointerIntPair<const ValueDecl*, 1, bool> DeclAndIsDerivedMember;
1542	/// Path - The path of base/derived classes from the member declaration's
1543	/// class (exclusive) to the class type of the member pointer (inclusive).
1544	SmallVector<const CXXRecordDecl*, 4> Path;
1545
1546	/// Perform a cast towards the class of the Decl (either up or down the
1547	/// hierarchy).
1548	bool castBack(const CXXRecordDecl *Class) {
1549	assert(!Path.empty());
1550	const CXXRecordDecl *Expected;
1551	if (Path.size() >= 2)
1552	Expected = Path[Path.size() - 2];
1553	else
1554	Expected = getContainingRecord();
1555	if (Expected->getCanonicalDecl() != Class->getCanonicalDecl()) {
1556	// C++11 [expr.static.cast]p12: In a conversion from (D::) to (B::),
1557	// if B does not contain the original member and is not a base or
1558	// derived class of the class containing the original member, the result
1559	// of the cast is undefined.
1560	// C++11 [conv.mem]p2 does not cover this case for a cast from (B::*) to
1561	// (D::*). We consider that to be a language defect.
1562	return false;
1563	}
1564	Path.pop_back();
1565	return true;
1566	}
1567	/// Perform a base-to-derived member pointer cast.
1568	bool castToDerived(const CXXRecordDecl *Derived) {
1569	if (!getDecl())
1570	return true;
1571	if (!isDerivedMember()) {
1572	Path.push_back(Derived);
1573	return true;
1574	}
1575	if (!castBack(Derived))
1576	return false;
1577	if (Path.empty())
1578	DeclAndIsDerivedMember.setInt(false);
1579	return true;
1580	}
1581	/// Perform a derived-to-base member pointer cast.
1582	bool castToBase(const CXXRecordDecl *Base) {
1583	if (!getDecl())
1584	return true;
1585	if (Path.empty())
1586	DeclAndIsDerivedMember.setInt(true);
1587	if (isDerivedMember()) {
1588	Path.push_back(Base);
1589	return true;
1590	}
1591	return castBack(Base);
1592	}
1593	};
1594
1595	/// Compare two member pointers, which are assumed to be of the same type.
1596	static bool operator==(const MemberPtr &LHS, const MemberPtr &RHS) {
1597	if (!LHS.getDecl() \|\| !RHS.getDecl())
1598	return !LHS.getDecl() && !RHS.getDecl();
1599	if (LHS.getDecl()->getCanonicalDecl() != RHS.getDecl()->getCanonicalDecl())
1600	return false;
1601	return LHS.Path == RHS.Path;
1602	}
1603	}
1604
1605	static bool Evaluate(APValue &Result, EvalInfo &Info, const Expr *E);
1606	static bool EvaluateInPlace(APValue &Result, EvalInfo &Info,
1607	const LValue &This, const Expr *E,
1608	bool AllowNonLiteralTypes = false);
1609	static bool EvaluateLValue(const Expr *E, LValue &Result, EvalInfo &Info,
1610	bool InvalidBaseOK = false);
1611	static bool EvaluatePointer(const Expr *E, LValue &Result, EvalInfo &Info,
1612	bool InvalidBaseOK = false);
1613	static bool EvaluateMemberPointer(const Expr *E, MemberPtr &Result,
1614	EvalInfo &Info);
1615	static bool EvaluateTemporary(const Expr *E, LValue &Result, EvalInfo &Info);
1616	static bool EvaluateInteger(const Expr *E, APSInt &Result, EvalInfo &Info);
1617	static bool EvaluateIntegerOrLValue(const Expr *E, APValue &Result,
1618	EvalInfo &Info);
1619	static bool EvaluateFloat(const Expr *E, APFloat &Result, EvalInfo &Info);
1620	static bool EvaluateComplex(const Expr *E, ComplexValue &Res, EvalInfo &Info);
1621	static bool EvaluateAtomic(const Expr E, const LValue This, APValue &Result,
1622	EvalInfo &Info);
1623	static bool EvaluateAsRValue(EvalInfo &Info, const Expr *E, APValue &Result);
1624
1625	/// Evaluate an integer or fixed point expression into an APResult.
1626	static bool EvaluateFixedPointOrInteger(const Expr *E, APFixedPoint &Result,
1627	EvalInfo &Info);
1628
1629	/// Evaluate only a fixed point expression into an APResult.
1630	static bool EvaluateFixedPoint(const Expr *E, APFixedPoint &Result,
1631	EvalInfo &Info);
1632
1633	//===----------------------------------------------------------------------===//
1634	// Misc utilities
1635	//===----------------------------------------------------------------------===//
1636
1637	/// A helper function to create a temporary and set an LValue.
1638	template <class KeyTy>
1639	static APValue &createTemporary(const KeyTy *Key, bool IsLifetimeExtended,
1640	LValue &LV, CallStackFrame &Frame) {
1641	LV.set({Key, Frame.Info.CurrentCall->Index,
1642	Frame.Info.CurrentCall->getTempVersion()});
1643	return Frame.createTemporary(Key, IsLifetimeExtended);
1644	}
1645
1646	/// Negate an APSInt in place, converting it to a signed form if necessary, and
1647	/// preserving its value (by extending by up to one bit as needed).
1648	static void negateAsSigned(APSInt &Int) {
1649	if (Int.isUnsigned() \|\| Int.isMinSignedValue()) {
1650	Int = Int.extend(Int.getBitWidth() + 1);
1651	Int.setIsSigned(true);
1652	}
1653	Int = -Int;
1654	}
1655
1656	/// Produce a string describing the given constexpr call.
1657	static void describeCall(CallStackFrame *Frame, raw_ostream &Out) {
1658	unsigned ArgIndex = 0;
1659	bool IsMemberCall = isa<CXXMethodDecl>(Frame->Callee) &&
1660	!isa<CXXConstructorDecl>(Frame->Callee) &&
1661	cast<CXXMethodDecl>(Frame->Callee)->isInstance();
1662
1663	if (!IsMemberCall)
1664	Out << *Frame->Callee << '(';
1665
1666	if (Frame->This && IsMemberCall) {
1667	APValue Val;
1668	Frame->This->moveInto(Val);
1669	Val.printPretty(Out, Frame->Info.Ctx,
1670	Frame->This->Designator.MostDerivedType);
1671	// FIXME: Add parens around Val if needed.
1672	Out << "->" << *Frame->Callee << '(';
1673	IsMemberCall = false;
1674	}
1675
1676	for (FunctionDecl::param_const_iterator I = Frame->Callee->param_begin(),
1677	E = Frame->Callee->param_end(); I != E; ++I, ++ArgIndex) {
1678	if (ArgIndex > (unsigned)IsMemberCall)
1679	Out << ", ";
1680
1681	const ParmVarDecl Param = I;
1682	const APValue &Arg = Frame->Arguments[ArgIndex];
1683	Arg.printPretty(Out, Frame->Info.Ctx, Param->getType());
1684
1685	if (ArgIndex == 0 && IsMemberCall)
1686	Out << "->" << *Frame->Callee << '(';
1687	}
1688
1689	Out << ')';
1690	}
1691
1692	/// Evaluate an expression to see if it had side-effects, and discard its
1693	/// result.
1694	/// \return \c true if the caller should keep evaluating.
1695	static bool EvaluateIgnoredValue(EvalInfo &Info, const Expr *E) {
1696	APValue Scratch;
1697	if (!Evaluate(Scratch, Info, E))
1698	// We don't need the value, but we might have skipped a side effect here.
1699	return Info.noteSideEffect();
1700	return true;
1701	}
1702
1703	/// Should this call expression be treated as a string literal?
1704	static bool IsStringLiteralCall(const CallExpr *E) {
1705	unsigned Builtin = E->getBuiltinCallee();
1706	return (Builtin == Builtin::BI__builtin___CFStringMakeConstantString \|\|
1707	Builtin == Builtin::BI__builtin___NSStringMakeConstantString);
1708	}
1709
1710	static bool IsGlobalLValue(APValue::LValueBase B) {
1711	// C++11 [expr.const]p3 An address constant expression is a prvalue core
1712	// constant expression of pointer type that evaluates to...
1713
1714	// ... a null pointer value, or a prvalue core constant expression of type
1715	// std::nullptr_t.
1716	if (!B) return true;
1717
1718	if (const ValueDecl D = B.dyn_cast<const ValueDecl>()) {
1719	// ... the address of an object with static storage duration,
1720	if (const VarDecl *VD = dyn_cast<VarDecl>(D))
1721	return VD->hasGlobalStorage();
1722	// ... the address of a function,
1723	return isa<FunctionDecl>(D);
1724	}
1725
1726	const Expr E = B.get<const Expr>();
1727	switch (E->getStmtClass()) {
1728	default:
1729	return false;
1730	case Expr::CompoundLiteralExprClass: {
1731	const CompoundLiteralExpr *CLE = cast<CompoundLiteralExpr>(E);
1732	return CLE->isFileScope() && CLE->isLValue();
1733	}
1734	case Expr::MaterializeTemporaryExprClass:
1735	// A materialized temporary might have been lifetime-extended to static
1736	// storage duration.
1737	return cast<MaterializeTemporaryExpr>(E)->getStorageDuration() == SD_Static;
1738	// A string literal has static storage duration.
1739	case Expr::StringLiteralClass:
1740	case Expr::PredefinedExprClass:
1741	case Expr::ObjCStringLiteralClass:
1742	case Expr::ObjCEncodeExprClass:
1743	case Expr::CXXTypeidExprClass:
1744	case Expr::CXXUuidofExprClass:
1745	return true;
1746	case Expr::ObjCBoxedExprClass:
1747	return cast<ObjCBoxedExpr>(E)->isExpressibleAsConstantInitializer();
1748	case Expr::CallExprClass:
1749	return IsStringLiteralCall(cast<CallExpr>(E));
1750	// For GCC compatibility, &&label has static storage duration.
1751	case Expr::AddrLabelExprClass:
1752	return true;
1753	// A Block literal expression may be used as the initialization value for
1754	// Block variables at global or local static scope.
1755	case Expr::BlockExprClass:
1756	return !cast<BlockExpr>(E)->getBlockDecl()->hasCaptures();
1757	case Expr::ImplicitValueInitExprClass:
1758	// FIXME:
1759	// We can never form an lvalue with an implicit value initialization as its
1760	// base through expression evaluation, so these only appear in one case: the
1761	// implicit variable declaration we invent when checking whether a constexpr
1762	// constructor can produce a constant expression. We must assume that such
1763	// an expression might be a global lvalue.
1764	return true;
1765	}
1766	}
1767
1768	static const ValueDecl *GetLValueBaseDecl(const LValue &LVal) {
1769	return LVal.Base.dyn_cast<const ValueDecl*>();
1770	}
1771
1772	static bool IsLiteralLValue(const LValue &Value) {
1773	if (Value.getLValueCallIndex())
1774	return false;
1775	const Expr E = Value.Base.dyn_cast<const Expr>();
1776	return E && !isa<MaterializeTemporaryExpr>(E);
1777	}
1778
1779	static bool IsWeakLValue(const LValue &Value) {
1780	const ValueDecl *Decl = GetLValueBaseDecl(Value);
1781	return Decl && Decl->isWeak();
1782	}
1783
1784	static bool isZeroSized(const LValue &Value) {
1785	const ValueDecl *Decl = GetLValueBaseDecl(Value);
1786	if (Decl && isa<VarDecl>(Decl)) {
1787	QualType Ty = Decl->getType();
1788	if (Ty->isArrayType())
1789	return Ty->isIncompleteType() \|\|
1790	Decl->getASTContext().getTypeSize(Ty) == 0;
1791	}
1792	return false;
1793	}
1794
1795	static bool HasSameBase(const LValue &A, const LValue &B) {
1796	if (!A.getLValueBase())
1797	return !B.getLValueBase();
1798	if (!B.getLValueBase())
1799	return false;
1800
1801	if (A.getLValueBase().getOpaqueValue() !=
1802	B.getLValueBase().getOpaqueValue()) {
1803	const Decl *ADecl = GetLValueBaseDecl(A);
1804	if (!ADecl)
1805	return false;
1806	const Decl *BDecl = GetLValueBaseDecl(B);
1807	if (!BDecl \|\| ADecl->getCanonicalDecl() != BDecl->getCanonicalDecl())
1808	return false;
1809	}
1810
1811	return IsGlobalLValue(A.getLValueBase()) \|\|
1812	(A.getLValueCallIndex() == B.getLValueCallIndex() &&
1813	A.getLValueVersion() == B.getLValueVersion());
1814	}
1815
1816	static void NoteLValueLocation(EvalInfo &Info, APValue::LValueBase Base) {
1817	(0) . __assert_fail ("Base && \"no location for a null lvalue\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 1817, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(Base && "no location for a null lvalue");
1818	const ValueDecl VD = Base.dyn_cast<const ValueDecl>();
1819	if (VD)
1820	Info.Note(VD->getLocation(), diag::note_declared_at);
1821	else
1822	Info.Note(Base.get<const Expr*>()->getExprLoc(),
1823	diag::note_constexpr_temporary_here);
1824	}
1825
1826	/// Check that this reference or pointer core constant expression is a valid
1827	/// value for an address or reference constant expression. Return true if we
1828	/// can fold this expression, whether or not it's a constant expression.
1829	static bool CheckLValueConstantExpression(EvalInfo &Info, SourceLocation Loc,
1830	QualType Type, const LValue &LVal,
1831	Expr::ConstExprUsage Usage) {
1832	bool IsReferenceType = Type->isReferenceType();
1833
1834	APValue::LValueBase Base = LVal.getLValueBase();
1835	const SubobjectDesignator &Designator = LVal.getLValueDesignator();
1836
1837	// Check that the object is a global. Note that the fake 'this' object we
1838	// manufacture when checking potential constant expressions is conservatively
1839	// assumed to be global here.
1840	if (!IsGlobalLValue(Base)) {
1841	if (Info.getLangOpts().CPlusPlus11) {
1842	const ValueDecl VD = Base.dyn_cast<const ValueDecl>();
1843	Info.FFDiag(Loc, diag::note_constexpr_non_global, 1)
1844	<< IsReferenceType << !Designator.Entries.empty()
1845	<< !!VD << VD;
1846	NoteLValueLocation(Info, Base);
1847	} else {
1848	Info.FFDiag(Loc);
1849	}
1850	// Don't allow references to temporaries to escape.
1851	return false;
1852	}
1853	(0) . __assert_fail ("(Info.checkingPotentialConstantExpression() \|\| LVal.getLValueCallIndex() == 0) && \"have call index for global lvalue\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 1855, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert((Info.checkingPotentialConstantExpression() \|\|
1854	(0) . __assert_fail ("(Info.checkingPotentialConstantExpression() \|\| LVal.getLValueCallIndex() == 0) && \"have call index for global lvalue\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 1855, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true"> LVal.getLValueCallIndex() == 0) &&
1855	(0) . __assert_fail ("(Info.checkingPotentialConstantExpression() \|\| LVal.getLValueCallIndex() == 0) && \"have call index for global lvalue\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 1855, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true"> "have call index for global lvalue");
1856
1857	if (const ValueDecl VD = Base.dyn_cast<const ValueDecl>()) {
1858	if (const VarDecl *Var = dyn_cast<const VarDecl>(VD)) {
1859	// Check if this is a thread-local variable.
1860	if (Var->getTLSKind())
1861	return false;
1862
1863	// A dllimport variable never acts like a constant.
1864	if (Usage == Expr::EvaluateForCodeGen && Var->hasAttr<DLLImportAttr>())
1865	return false;
1866	}
1867	if (const auto *FD = dyn_cast<const FunctionDecl>(VD)) {
1868	// __declspec(dllimport) must be handled very carefully:
1869	// We must never initialize an expression with the thunk in C++.
1870	// Doing otherwise would allow the same id-expression to yield
1871	// different addresses for the same function in different translation
1872	// units. However, this means that we must dynamically initialize the
1873	// expression with the contents of the import address table at runtime.
1874	//
1875	// The C language has no notion of ODR; furthermore, it has no notion of
1876	// dynamic initialization. This means that we are permitted to
1877	// perform initialization with the address of the thunk.
1878	if (Info.getLangOpts().CPlusPlus && Usage == Expr::EvaluateForCodeGen &&
1879	FD->hasAttr<DLLImportAttr>())
1880	return false;
1881	}
1882	}
1883
1884	// Allow address constant expressions to be past-the-end pointers. This is
1885	// an extension: the standard requires them to point to an object.
1886	if (!IsReferenceType)
1887	return true;
1888
1889	// A reference constant expression must refer to an object.
1890	if (!Base) {
1891	// FIXME: diagnostic
1892	Info.CCEDiag(Loc);
1893	return true;
1894	}
1895
1896	// Does this refer one past the end of some object?
1897	if (!Designator.Invalid && Designator.isOnePastTheEnd()) {
1898	const ValueDecl VD = Base.dyn_cast<const ValueDecl>();
1899	Info.FFDiag(Loc, diag::note_constexpr_past_end, 1)
1900	<< !Designator.Entries.empty() << !!VD << VD;
1901	NoteLValueLocation(Info, Base);
1902	}
1903
1904	return true;
1905	}
1906
1907	/// Member pointers are constant expressions unless they point to a
1908	/// non-virtual dllimport member function.
1909	static bool CheckMemberPointerConstantExpression(EvalInfo &Info,
1910	SourceLocation Loc,
1911	QualType Type,
1912	const APValue &Value,
1913	Expr::ConstExprUsage Usage) {
1914	const ValueDecl *Member = Value.getMemberPointerDecl();
1915	const auto *FD = dyn_cast_or_null<CXXMethodDecl>(Member);
1916	if (!FD)
1917	return true;
1918	return Usage == Expr::EvaluateForMangling \|\| FD->isVirtual() \|\|
1919	!FD->hasAttr<DLLImportAttr>();
1920	}
1921
1922	/// Check that this core constant expression is of literal type, and if not,
1923	/// produce an appropriate diagnostic.
1924	static bool CheckLiteralType(EvalInfo &Info, const Expr *E,
1925	const LValue *This = nullptr) {
1926	if (!E->isRValue() \|\| E->getType()->isLiteralType(Info.Ctx))
1927	return true;
1928
1929	// C++1y: A constant initializer for an object o [...] may also invoke
1930	// constexpr constructors for o and its subobjects even if those objects
1931	// are of non-literal class types.
1932	//
1933	// C++11 missed this detail for aggregates, so classes like this:
1934	// struct foo_t { union { int i; volatile int j; } u; };
1935	// are not (obviously) initializable like so:
1936	// __attribute__((__require_constant_initialization__))
1937	// static const foo_t x = {{0}};
1938	// because "i" is a subobject with non-literal initialization (due to the
1939	// volatile member of the union). See:
1940	// http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#1677
1941	// Therefore, we use the C++1y behavior.
1942	if (This && Info.EvaluatingDecl == This->getLValueBase())
1943	return true;
1944
1945	// Prvalue constant expressions must be of literal types.
1946	if (Info.getLangOpts().CPlusPlus11)
1947	Info.FFDiag(E, diag::note_constexpr_nonliteral)
1948	<< E->getType();
1949	else
1950	Info.FFDiag(E, diag::note_invalid_subexpr_in_const_expr);
1951	return false;
1952	}
1953
1954	/// Check that this core constant expression value is a valid value for a
1955	/// constant expression. If not, report an appropriate diagnostic. Does not
1956	/// check that the expression is of literal type.
1957	static bool
1958	CheckConstantExpression(EvalInfo &Info, SourceLocation DiagLoc, QualType Type,
1959	const APValue &Value,
1960	Expr::ConstExprUsage Usage = Expr::EvaluateForCodeGen) {
1961	if (Value.isUninit()) {
1962	Info.FFDiag(DiagLoc, diag::note_constexpr_uninitialized)
1963	<< true << Type;
1964	return false;
1965	}
1966
1967	// We allow _Atomic(T) to be initialized from anything that T can be
1968	// initialized from.
1969	if (const AtomicType *AT = Type->getAs<AtomicType>())
1970	Type = AT->getValueType();
1971
1972	// Core issue 1454: For a literal constant expression of array or class type,
1973	// each subobject of its value shall have been initialized by a constant
1974	// expression.
1975	if (Value.isArray()) {
1976	QualType EltTy = Type->castAsArrayTypeUnsafe()->getElementType();
1977	for (unsigned I = 0, N = Value.getArrayInitializedElts(); I != N; ++I) {
1978	if (!CheckConstantExpression(Info, DiagLoc, EltTy,
1979	Value.getArrayInitializedElt(I), Usage))
1980	return false;
1981	}
1982	if (!Value.hasArrayFiller())
1983	return true;
1984	return CheckConstantExpression(Info, DiagLoc, EltTy, Value.getArrayFiller(),
1985	Usage);
1986	}
1987	if (Value.isUnion() && Value.getUnionField()) {
1988	return CheckConstantExpression(Info, DiagLoc,
1989	Value.getUnionField()->getType(),
1990	Value.getUnionValue(), Usage);
1991	}
1992	if (Value.isStruct()) {
1993	RecordDecl *RD = Type->castAs<RecordType>()->getDecl();
1994	if (const CXXRecordDecl *CD = dyn_cast<CXXRecordDecl>(RD)) {
1995	unsigned BaseIndex = 0;
1996	for (const CXXBaseSpecifier &BS : CD->bases()) {
1997	if (!CheckConstantExpression(Info, DiagLoc, BS.getType(),
1998	Value.getStructBase(BaseIndex), Usage))
1999	return false;
2000	++BaseIndex;
2001	}
2002	}
2003	for (const auto *I : RD->fields()) {
2004	if (I->isUnnamedBitfield())
2005	continue;
2006
2007	if (!CheckConstantExpression(Info, DiagLoc, I->getType(),
2008	Value.getStructField(I->getFieldIndex()),
2009	Usage))
2010	return false;
2011	}
2012	}
2013
2014	if (Value.isLValue()) {
2015	LValue LVal;
2016	LVal.setFrom(Info.Ctx, Value);
2017	return CheckLValueConstantExpression(Info, DiagLoc, Type, LVal, Usage);
2018	}
2019
2020	if (Value.isMemberPointer())
2021	return CheckMemberPointerConstantExpression(Info, DiagLoc, Type, Value, Usage);
2022
2023	// Everything else is fine.
2024	return true;
2025	}
2026
2027	static bool EvalPointerValueAsBool(const APValue &Value, bool &Result) {
2028	// A null base expression indicates a null pointer. These are always
2029	// evaluatable, and they are false unless the offset is zero.
2030	if (!Value.getLValueBase()) {
2031	Result = !Value.getLValueOffset().isZero();
2032	return true;
2033	}
2034
2035	// We have a non-null base. These are generally known to be true, but if it's
2036	// a weak declaration it can be null at runtime.
2037	Result = true;
2038	const ValueDecl Decl = Value.getLValueBase().dyn_cast<const ValueDecl>();
2039	return !Decl \|\| !Decl->isWeak();
2040	}
2041
2042	static bool HandleConversionToBool(const APValue &Val, bool &Result) {
2043	switch (Val.getKind()) {
2044	case APValue::Uninitialized:
2045	return false;
2046	case APValue::Int:
2047	Result = Val.getInt().getBoolValue();
2048	return true;
2049	case APValue::FixedPoint:
2050	Result = Val.getFixedPoint().getBoolValue();
2051	return true;
2052	case APValue::Float:
2053	Result = !Val.getFloat().isZero();
2054	return true;
2055	case APValue::ComplexInt:
2056	Result = Val.getComplexIntReal().getBoolValue() \|\|
2057	Val.getComplexIntImag().getBoolValue();
2058	return true;
2059	case APValue::ComplexFloat:
2060	Result = !Val.getComplexFloatReal().isZero() \|\|
2061	!Val.getComplexFloatImag().isZero();
2062	return true;
2063	case APValue::LValue:
2064	return EvalPointerValueAsBool(Val, Result);
2065	case APValue::MemberPointer:
2066	Result = Val.getMemberPointerDecl();
2067	return true;
2068	case APValue::Vector:
2069	case APValue::Array:
2070	case APValue::Struct:
2071	case APValue::Union:
2072	case APValue::AddrLabelDiff:
2073	return false;
2074	}
2075
2076	llvm_unreachable("unknown APValue kind");
2077	}
2078
2079	static bool EvaluateAsBooleanCondition(const Expr *E, bool &Result,
2080	EvalInfo &Info) {
2081	(0) . __assert_fail ("E->isRValue() && \"missing lvalue-to-rvalue conv in bool condition\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 2081, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(E->isRValue() && "missing lvalue-to-rvalue conv in bool condition");
2082	APValue Val;
2083	if (!Evaluate(Val, Info, E))
2084	return false;
2085	return HandleConversionToBool(Val, Result);
2086	}
2087
2088	template<typename T>
2089	static bool HandleOverflow(EvalInfo &Info, const Expr *E,
2090	const T &SrcValue, QualType DestType) {
2091	Info.CCEDiag(E, diag::note_constexpr_overflow)
2092	<< SrcValue << DestType;
2093	return Info.noteUndefinedBehavior();
2094	}
2095
2096	static bool HandleFloatToIntCast(EvalInfo &Info, const Expr *E,
2097	QualType SrcType, const APFloat &Value,
2098	QualType DestType, APSInt &Result) {
2099	unsigned DestWidth = Info.Ctx.getIntWidth(DestType);
2100	// Determine whether we are converting to unsigned or signed.
2101	bool DestSigned = DestType->isSignedIntegerOrEnumerationType();
2102
2103	Result = APSInt(DestWidth, !DestSigned);
2104	bool ignored;
2105	if (Value.convertToInteger(Result, llvm::APFloat::rmTowardZero, &ignored)
2106	& APFloat::opInvalidOp)
2107	return HandleOverflow(Info, E, Value, DestType);
2108	return true;
2109	}
2110
2111	static bool HandleFloatToFloatCast(EvalInfo &Info, const Expr *E,
2112	QualType SrcType, QualType DestType,
2113	APFloat &Result) {
2114	APFloat Value = Result;
2115	bool ignored;
2116	if (Result.convert(Info.Ctx.getFloatTypeSemantics(DestType),
2117	APFloat::rmNearestTiesToEven, &ignored)
2118	& APFloat::opOverflow)
2119	return HandleOverflow(Info, E, Value, DestType);
2120	return true;
2121	}
2122
2123	static APSInt HandleIntToIntCast(EvalInfo &Info, const Expr *E,
2124	QualType DestType, QualType SrcType,
2125	const APSInt &Value) {
2126	unsigned DestWidth = Info.Ctx.getIntWidth(DestType);
2127	// Figure out if this is a truncate, extend or noop cast.
2128	// If the input is signed, do a sign extend, noop, or truncate.
2129	APSInt Result = Value.extOrTrunc(DestWidth);
2130	Result.setIsUnsigned(DestType->isUnsignedIntegerOrEnumerationType());
2131	if (DestType->isBooleanType())
2132	Result = Value.getBoolValue();
2133	return Result;
2134	}
2135
2136	static bool HandleIntToFloatCast(EvalInfo &Info, const Expr *E,
2137	QualType SrcType, const APSInt &Value,
2138	QualType DestType, APFloat &Result) {
2139	Result = APFloat(Info.Ctx.getFloatTypeSemantics(DestType), 1);
2140	if (Result.convertFromAPInt(Value, Value.isSigned(),
2141	APFloat::rmNearestTiesToEven)
2142	& APFloat::opOverflow)
2143	return HandleOverflow(Info, E, Value, DestType);
2144	return true;
2145	}
2146
2147	static bool truncateBitfieldValue(EvalInfo &Info, const Expr *E,
2148	APValue &Value, const FieldDecl *FD) {
2149	(0) . __assert_fail ("FD->isBitField() && \"truncateBitfieldValue on non-bitfield\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 2149, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(FD->isBitField() && "truncateBitfieldValue on non-bitfield");
2150
2151	if (!Value.isInt()) {
2152	// Trying to store a pointer-cast-to-integer into a bitfield.
2153	// FIXME: In this case, we should provide the diagnostic for casting
2154	// a pointer to an integer.
2155	(0) . __assert_fail ("Value.isLValue() && \"integral value neither int nor lvalue?\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 2155, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(Value.isLValue() && "integral value neither int nor lvalue?");
2156	Info.FFDiag(E);
2157	return false;
2158	}
2159
2160	APSInt &Int = Value.getInt();
2161	unsigned OldBitWidth = Int.getBitWidth();
2162	unsigned NewBitWidth = FD->getBitWidthValue(Info.Ctx);
2163	if (NewBitWidth < OldBitWidth)
2164	Int = Int.trunc(NewBitWidth).extend(OldBitWidth);
2165	return true;
2166	}
2167
2168	static bool EvalAndBitcastToAPInt(EvalInfo &Info, const Expr *E,
2169	llvm::APInt &Res) {
2170	APValue SVal;
2171	if (!Evaluate(SVal, Info, E))
2172	return false;
2173	if (SVal.isInt()) {
2174	Res = SVal.getInt();
2175	return true;
2176	}
2177	if (SVal.isFloat()) {
2178	Res = SVal.getFloat().bitcastToAPInt();
2179	return true;
2180	}
2181	if (SVal.isVector()) {
2182	QualType VecTy = E->getType();
2183	unsigned VecSize = Info.Ctx.getTypeSize(VecTy);
2184	QualType EltTy = VecTy->castAs<VectorType>()->getElementType();
2185	unsigned EltSize = Info.Ctx.getTypeSize(EltTy);
2186	bool BigEndian = Info.Ctx.getTargetInfo().isBigEndian();
2187	Res = llvm::APInt::getNullValue(VecSize);
2188	for (unsigned i = 0; i < SVal.getVectorLength(); i++) {
2189	APValue &Elt = SVal.getVectorElt(i);
2190	llvm::APInt EltAsInt;
2191	if (Elt.isInt()) {
2192	EltAsInt = Elt.getInt();
2193	} else if (Elt.isFloat()) {
2194	EltAsInt = Elt.getFloat().bitcastToAPInt();
2195	} else {
2196	// Don't try to handle vectors of anything other than int or float
2197	// (not sure if it's possible to hit this case).
2198	Info.FFDiag(E, diag::note_invalid_subexpr_in_const_expr);
2199	return false;
2200	}
2201	unsigned BaseEltSize = EltAsInt.getBitWidth();
2202	if (BigEndian)
2203	Res \|= EltAsInt.zextOrTrunc(VecSize).rotr(i*EltSize+BaseEltSize);
2204	else
2205	Res \|= EltAsInt.zextOrTrunc(VecSize).rotl(i*EltSize);
2206	}
2207	return true;
2208	}
2209	// Give up if the input isn't an int, float, or vector. For example, we
2210	// reject "(v4i16)(intptr_t)&a".
2211	Info.FFDiag(E, diag::note_invalid_subexpr_in_const_expr);
2212	return false;
2213	}
2214
2215	/// Perform the given integer operation, which is known to need at most BitWidth
2216	/// bits, and check for overflow in the original type (if that type was not an
2217	/// unsigned type).
2218	template<typename Operation>
2219	static bool CheckedIntArithmetic(EvalInfo &Info, const Expr *E,
2220	const APSInt &LHS, const APSInt &RHS,
2221	unsigned BitWidth, Operation Op,
2222	APSInt &Result) {
2223	if (LHS.isUnsigned()) {
2224	Result = Op(LHS, RHS);
2225	return true;
2226	}
2227
2228	APSInt Value(Op(LHS.extend(BitWidth), RHS.extend(BitWidth)), false);
2229	Result = Value.trunc(LHS.getBitWidth());
2230	if (Result.extend(BitWidth) != Value) {
2231	if (Info.checkingForOverflow())
2232	Info.Ctx.getDiagnostics().Report(E->getExprLoc(),
2233	diag::warn_integer_constant_overflow)
2234	<< Result.toString(10) << E->getType();
2235	else
2236	return HandleOverflow(Info, E, Value, E->getType());
2237	}
2238	return true;
2239	}
2240
2241	/// Perform the given binary integer operation.
2242	static bool handleIntIntBinOp(EvalInfo &Info, const Expr *E, const APSInt &LHS,
2243	BinaryOperatorKind Opcode, APSInt RHS,
2244	APSInt &Result) {
2245	switch (Opcode) {
2246	default:
2247	Info.FFDiag(E);
2248	return false;
2249	case BO_Mul:
2250	return CheckedIntArithmetic(Info, E, LHS, RHS, LHS.getBitWidth() * 2,
2251	std::multiplies<APSInt>(), Result);
2252	case BO_Add:
2253	return CheckedIntArithmetic(Info, E, LHS, RHS, LHS.getBitWidth() + 1,
2254	std::plus<APSInt>(), Result);
2255	case BO_Sub:
2256	return CheckedIntArithmetic(Info, E, LHS, RHS, LHS.getBitWidth() + 1,
2257	std::minus<APSInt>(), Result);
2258	case BO_And: Result = LHS & RHS; return true;
2259	case BO_Xor: Result = LHS ^ RHS; return true;
2260	case BO_Or: Result = LHS \| RHS; return true;
2261	case BO_Div:
2262	case BO_Rem:
2263	if (RHS == 0) {
2264	Info.FFDiag(E, diag::note_expr_divide_by_zero);
2265	return false;
2266	}
2267	Result = (Opcode == BO_Rem ? LHS % RHS : LHS / RHS);
2268	// Check for overflow case: INT_MIN / -1 or INT_MIN % -1. APSInt supports
2269	// this operation and gives the two's complement result.
2270	if (RHS.isNegative() && RHS.isAllOnesValue() &&
2271	LHS.isSigned() && LHS.isMinSignedValue())
2272	return HandleOverflow(Info, E, -LHS.extend(LHS.getBitWidth() + 1),
2273	E->getType());
2274	return true;
2275	case BO_Shl: {
2276	if (Info.getLangOpts().OpenCL)
2277	// OpenCL 6.3j: shift values are effectively % word size of LHS.
2278	RHS &= APSInt(llvm::APInt(RHS.getBitWidth(),
2279	static_cast<uint64_t>(LHS.getBitWidth() - 1)),
2280	RHS.isUnsigned());
2281	else if (RHS.isSigned() && RHS.isNegative()) {
2282	// During constant-folding, a negative shift is an opposite shift. Such
2283	// a shift is not a constant expression.
2284	Info.CCEDiag(E, diag::note_constexpr_negative_shift) << RHS;
2285	RHS = -RHS;
2286	goto shift_right;
2287	}
2288	shift_left:
2289	// C++11 [expr.shift]p1: Shift width must be less than the bit width of
2290	// the shifted type.
2291	unsigned SA = (unsigned) RHS.getLimitedValue(LHS.getBitWidth()-1);
2292	if (SA != RHS) {
2293	Info.CCEDiag(E, diag::note_constexpr_large_shift)
2294	<< RHS << E->getType() << LHS.getBitWidth();
2295	} else if (LHS.isSigned()) {
2296	// C++11 [expr.shift]p2: A signed left shift must have a non-negative
2297	// operand, and must not overflow the corresponding unsigned type.
2298	if (LHS.isNegative())
2299	Info.CCEDiag(E, diag::note_constexpr_lshift_of_negative) << LHS;
2300	else if (LHS.countLeadingZeros() < SA)
2301	Info.CCEDiag(E, diag::note_constexpr_lshift_discards);
2302	}
2303	Result = LHS << SA;
2304	return true;
2305	}
2306	case BO_Shr: {
2307	if (Info.getLangOpts().OpenCL)
2308	// OpenCL 6.3j: shift values are effectively % word size of LHS.
2309	RHS &= APSInt(llvm::APInt(RHS.getBitWidth(),
2310	static_cast<uint64_t>(LHS.getBitWidth() - 1)),
2311	RHS.isUnsigned());
2312	else if (RHS.isSigned() && RHS.isNegative()) {
2313	// During constant-folding, a negative shift is an opposite shift. Such a
2314	// shift is not a constant expression.
2315	Info.CCEDiag(E, diag::note_constexpr_negative_shift) << RHS;
2316	RHS = -RHS;
2317	goto shift_left;
2318	}
2319	shift_right:
2320	// C++11 [expr.shift]p1: Shift width must be less than the bit width of the
2321	// shifted type.
2322	unsigned SA = (unsigned) RHS.getLimitedValue(LHS.getBitWidth()-1);
2323	if (SA != RHS)
2324	Info.CCEDiag(E, diag::note_constexpr_large_shift)
2325	<< RHS << E->getType() << LHS.getBitWidth();
2326	Result = LHS >> SA;
2327	return true;
2328	}
2329
2330	case BO_LT: Result = LHS < RHS; return true;
2331	case BO_GT: Result = LHS > RHS; return true;
2332	case BO_LE: Result = LHS <= RHS; return true;
2333	case BO_GE: Result = LHS >= RHS; return true;
2334	case BO_EQ: Result = LHS == RHS; return true;
2335	case BO_NE: Result = LHS != RHS; return true;
2336	case BO_Cmp:
2337	llvm_unreachable("BO_Cmp should be handled elsewhere");
2338	}
2339	}
2340
2341	/// Perform the given binary floating-point operation, in-place, on LHS.
2342	static bool handleFloatFloatBinOp(EvalInfo &Info, const Expr *E,
2343	APFloat &LHS, BinaryOperatorKind Opcode,
2344	const APFloat &RHS) {
2345	switch (Opcode) {
2346	default:
2347	Info.FFDiag(E);
2348	return false;
2349	case BO_Mul:
2350	LHS.multiply(RHS, APFloat::rmNearestTiesToEven);
2351	break;
2352	case BO_Add:
2353	LHS.add(RHS, APFloat::rmNearestTiesToEven);
2354	break;
2355	case BO_Sub:
2356	LHS.subtract(RHS, APFloat::rmNearestTiesToEven);
2357	break;
2358	case BO_Div:
2359	LHS.divide(RHS, APFloat::rmNearestTiesToEven);
2360	break;
2361	}
2362
2363	if (LHS.isInfinity() \|\| LHS.isNaN()) {
2364	Info.CCEDiag(E, diag::note_constexpr_float_arithmetic) << LHS.isNaN();
2365	return Info.noteUndefinedBehavior();
2366	}
2367	return true;
2368	}
2369
2370	/// Cast an lvalue referring to a base subobject to a derived class, by
2371	/// truncating the lvalue's path to the given length.
2372	static bool CastToDerivedClass(EvalInfo &Info, const Expr *E, LValue &Result,
2373	const RecordDecl *TruncatedType,
2374	unsigned TruncatedElements) {
2375	SubobjectDesignator &D = Result.Designator;
2376
2377	// Check we actually point to a derived class object.
2378	if (TruncatedElements == D.Entries.size())
2379	return true;
2380	(0) . __assert_fail ("TruncatedElements >= D.MostDerivedPathLength && \"not casting to a derived class\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 2381, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(TruncatedElements >= D.MostDerivedPathLength &&
2381	(0) . __assert_fail ("TruncatedElements >= D.MostDerivedPathLength && \"not casting to a derived class\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 2381, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true"> "not casting to a derived class");
2382	if (!Result.checkSubobject(Info, E, CSK_Derived))
2383	return false;
2384
2385	// Truncate the path to the subobject, and remove any derived-to-base offsets.
2386	const RecordDecl *RD = TruncatedType;
2387	for (unsigned I = TruncatedElements, N = D.Entries.size(); I != N; ++I) {
2388	if (RD->isInvalidDecl()) return false;
2389	const ASTRecordLayout &Layout = Info.Ctx.getASTRecordLayout(RD);
2390	const CXXRecordDecl *Base = getAsBaseClass(D.Entries[I]);
2391	if (isVirtualBaseClass(D.Entries[I]))
2392	Result.Offset -= Layout.getVBaseClassOffset(Base);
2393	else
2394	Result.Offset -= Layout.getBaseClassOffset(Base);
2395	RD = Base;
2396	}
2397	D.Entries.resize(TruncatedElements);
2398	return true;
2399	}
2400
2401	static bool HandleLValueDirectBase(EvalInfo &Info, const Expr *E, LValue &Obj,
2402	const CXXRecordDecl *Derived,
2403	const CXXRecordDecl *Base,
2404	const ASTRecordLayout *RL = nullptr) {
2405	if (!RL) {
2406	if (Derived->isInvalidDecl()) return false;
2407	RL = &Info.Ctx.getASTRecordLayout(Derived);
2408	}
2409
2410	Obj.getLValueOffset() += RL->getBaseClassOffset(Base);
2411	Obj.addDecl(Info, E, Base, /Virtual/ false);
2412	return true;
2413	}
2414
2415	static bool HandleLValueBase(EvalInfo &Info, const Expr *E, LValue &Obj,
2416	const CXXRecordDecl *DerivedDecl,
2417	const CXXBaseSpecifier *Base) {
2418	const CXXRecordDecl *BaseDecl = Base->getType()->getAsCXXRecordDecl();
2419
2420	if (!Base->isVirtual())
2421	return HandleLValueDirectBase(Info, E, Obj, DerivedDecl, BaseDecl);
2422
2423	SubobjectDesignator &D = Obj.Designator;
2424	if (D.Invalid)
2425	return false;
2426
2427	// Extract most-derived object and corresponding type.
2428	DerivedDecl = D.MostDerivedType->getAsCXXRecordDecl();
2429	if (!CastToDerivedClass(Info, E, Obj, DerivedDecl, D.MostDerivedPathLength))
2430	return false;
2431
2432	// Find the virtual base class.
2433	if (DerivedDecl->isInvalidDecl()) return false;
2434	const ASTRecordLayout &Layout = Info.Ctx.getASTRecordLayout(DerivedDecl);
2435	Obj.getLValueOffset() += Layout.getVBaseClassOffset(BaseDecl);
2436	Obj.addDecl(Info, E, BaseDecl, /Virtual/ true);
2437	return true;
2438	}
2439
2440	static bool HandleLValueBasePath(EvalInfo &Info, const CastExpr *E,
2441	QualType Type, LValue &Result) {
2442	for (CastExpr::path_const_iterator PathI = E->path_begin(),
2443	PathE = E->path_end();
2444	PathI != PathE; ++PathI) {
2445	if (!HandleLValueBase(Info, E, Result, Type->getAsCXXRecordDecl(),
2446	*PathI))
2447	return false;
2448	Type = (*PathI)->getType();
2449	}
2450	return true;
2451	}
2452
2453	/// Update LVal to refer to the given field, which must be a member of the type
2454	/// currently described by LVal.
2455	static bool HandleLValueMember(EvalInfo &Info, const Expr *E, LValue &LVal,
2456	const FieldDecl *FD,
2457	const ASTRecordLayout *RL = nullptr) {
2458	if (!RL) {
2459	if (FD->getParent()->isInvalidDecl()) return false;
2460	RL = &Info.Ctx.getASTRecordLayout(FD->getParent());
2461	}
2462
2463	unsigned I = FD->getFieldIndex();
2464	LVal.adjustOffset(Info.Ctx.toCharUnitsFromBits(RL->getFieldOffset(I)));
2465	LVal.addDecl(Info, E, FD);
2466	return true;
2467	}
2468
2469	/// Update LVal to refer to the given indirect field.
2470	static bool HandleLValueIndirectMember(EvalInfo &Info, const Expr *E,
2471	LValue &LVal,
2472	const IndirectFieldDecl *IFD) {
2473	for (const auto *C : IFD->chain())
2474	if (!HandleLValueMember(Info, E, LVal, cast<FieldDecl>(C)))
2475	return false;
2476	return true;
2477	}
2478
2479	/// Get the size of the given type in char units.
2480	static bool HandleSizeof(EvalInfo &Info, SourceLocation Loc,
2481	QualType Type, CharUnits &Size) {
2482	// sizeof(void), __alignof__(void), sizeof(function) = 1 as a gcc
2483	// extension.
2484	if (Type->isVoidType() \|\| Type->isFunctionType()) {
2485	Size = CharUnits::One();
2486	return true;
2487	}
2488
2489	if (Type->isDependentType()) {
2490	Info.FFDiag(Loc);
2491	return false;
2492	}
2493
2494	if (!Type->isConstantSizeType()) {
2495	// sizeof(vla) is not a constantexpr: C99 6.5.3.4p2.
2496	// FIXME: Better diagnostic.
2497	Info.FFDiag(Loc);
2498	return false;
2499	}
2500
2501	Size = Info.Ctx.getTypeSizeInChars(Type);
2502	return true;
2503	}
2504
2505	/// Update a pointer value to model pointer arithmetic.
2506	/// \param Info - Information about the ongoing evaluation.
2507	/// \param E - The expression being evaluated, for diagnostic purposes.
2508	/// \param LVal - The pointer value to be updated.
2509	/// \param EltTy - The pointee type represented by LVal.
2510	/// \param Adjustment - The adjustment, in objects of type EltTy, to add.
2511	static bool HandleLValueArrayAdjustment(EvalInfo &Info, const Expr *E,
2512	LValue &LVal, QualType EltTy,
2513	APSInt Adjustment) {
2514	CharUnits SizeOfPointee;
2515	if (!HandleSizeof(Info, E->getExprLoc(), EltTy, SizeOfPointee))
2516	return false;
2517
2518	LVal.adjustOffsetAndIndex(Info, E, Adjustment, SizeOfPointee);
2519	return true;
2520	}
2521
2522	static bool HandleLValueArrayAdjustment(EvalInfo &Info, const Expr *E,
2523	LValue &LVal, QualType EltTy,
2524	int64_t Adjustment) {
2525	return HandleLValueArrayAdjustment(Info, E, LVal, EltTy,
2526	APSInt::get(Adjustment));
2527	}
2528
2529	/// Update an lvalue to refer to a component of a complex number.
2530	/// \param Info - Information about the ongoing evaluation.
2531	/// \param LVal - The lvalue to be updated.
2532	/// \param EltTy - The complex number's component type.
2533	/// \param Imag - False for the real component, true for the imaginary.
2534	static bool HandleLValueComplexElement(EvalInfo &Info, const Expr *E,
2535	LValue &LVal, QualType EltTy,
2536	bool Imag) {
2537	if (Imag) {
2538	CharUnits SizeOfComponent;
2539	if (!HandleSizeof(Info, E->getExprLoc(), EltTy, SizeOfComponent))
2540	return false;
2541	LVal.Offset += SizeOfComponent;
2542	}
2543	LVal.addComplex(Info, E, EltTy, Imag);
2544	return true;
2545	}
2546
2547	static bool handleLValueToRValueConversion(EvalInfo &Info, const Expr *Conv,
2548	QualType Type, const LValue &LVal,
2549	APValue &RVal);
2550
2551	/// Try to evaluate the initializer for a variable declaration.
2552	///
2553	/// \param Info Information about the ongoing evaluation.
2554	/// \param E An expression to be used when printing diagnostics.
2555	/// \param VD The variable whose initializer should be obtained.
2556	/// \param Frame The frame in which the variable was created. Must be null
2557	/// if this variable is not local to the evaluation.
2558	/// \param Result Filled in with a pointer to the value of the variable.
2559	static bool evaluateVarDeclInit(EvalInfo &Info, const Expr *E,
2560	const VarDecl VD, CallStackFrame Frame,
2561	APValue &Result, const LValue LVal) {
2562
2563	// If this is a parameter to an active constexpr function call, perform
2564	// argument substitution.
2565	if (const ParmVarDecl *PVD = dyn_cast<ParmVarDecl>(VD)) {
2566	// Assume arguments of a potential constant expression are unknown
2567	// constant expressions.
2568	if (Info.checkingPotentialConstantExpression())
2569	return false;
2570	if (!Frame \|\| !Frame->Arguments) {
2571	Info.FFDiag(E, diag::note_invalid_subexpr_in_const_expr);
2572	return false;
2573	}
2574	Result = &Frame->Arguments[PVD->getFunctionScopeIndex()];
2575	return true;
2576	}
2577
2578	// If this is a local variable, dig out its value.
2579	if (Frame) {
2580	Result = LVal ? Frame->getTemporary(VD, LVal->getLValueVersion())
2581	: Frame->getCurrentTemporary(VD);
2582	if (!Result) {
2583	// Assume variables referenced within a lambda's call operator that were
2584	// not declared within the call operator are captures and during checking
2585	// of a potential constant expression, assume they are unknown constant
2586	// expressions.
2587	(0) . __assert_fail ("isLambdaCallOperator(Frame->Callee) && (VD->getDeclContext() != Frame->Callee \|\| VD->isInitCapture()) && \"missing value for local variable\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 2589, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(isLambdaCallOperator(Frame->Callee) &&
2588	(0) . __assert_fail ("isLambdaCallOperator(Frame->Callee) && (VD->getDeclContext() != Frame->Callee \|\| VD->isInitCapture()) && \"missing value for local variable\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 2589, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true"> (VD->getDeclContext() != Frame->Callee \|\| VD->isInitCapture()) &&
2589	(0) . __assert_fail ("isLambdaCallOperator(Frame->Callee) && (VD->getDeclContext() != Frame->Callee \|\| VD->isInitCapture()) && \"missing value for local variable\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 2589, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true"> "missing value for local variable");
2590	if (Info.checkingPotentialConstantExpression())
2591	return false;
2592	// FIXME: implement capture evaluation during constant expr evaluation.
2593	Info.FFDiag(E->getBeginLoc(),
2594	diag::note_unimplemented_constexpr_lambda_feature_ast)
2595	<< "captures not currently allowed";
2596	return false;
2597	}
2598	return true;
2599	}
2600
2601	// Dig out the initializer, and use the declaration which it's attached to.
2602	const Expr *Init = VD->getAnyInitializer(VD);
2603	if (!Init \|\| Init->isValueDependent()) {
2604	// If we're checking a potential constant expression, the variable could be
2605	// initialized later.
2606	if (!Info.checkingPotentialConstantExpression())
2607	Info.FFDiag(E, diag::note_invalid_subexpr_in_const_expr);
2608	return false;
2609	}
2610
2611	// If we're currently evaluating the initializer of this declaration, use that
2612	// in-flight value.
2613	if (Info.EvaluatingDecl.dyn_cast<const ValueDecl*>() == VD) {
2614	Result = Info.EvaluatingDeclValue;
2615	return true;
2616	}
2617
2618	// Never evaluate the initializer of a weak variable. We can't be sure that
2619	// this is the definition which will be used.
2620	if (VD->isWeak()) {
2621	Info.FFDiag(E, diag::note_invalid_subexpr_in_const_expr);
2622	return false;
2623	}
2624
2625	// Check that we can fold the initializer. In C++, we will have already done
2626	// this in the cases where it matters for conformance.
2627	SmallVector<PartialDiagnosticAt, 8> Notes;
2628	if (!VD->evaluateValue(Notes)) {
2629	Info.FFDiag(E, diag::note_constexpr_var_init_non_constant,
2630	Notes.size() + 1) << VD;
2631	Info.Note(VD->getLocation(), diag::note_declared_at);
2632	Info.addNotes(Notes);
2633	return false;
2634	} else if (!VD->checkInitIsICE()) {
2635	Info.CCEDiag(E, diag::note_constexpr_var_init_non_constant,
2636	Notes.size() + 1) << VD;
2637	Info.Note(VD->getLocation(), diag::note_declared_at);
2638	Info.addNotes(Notes);
2639	}
2640
2641	Result = VD->getEvaluatedValue();
2642	return true;
2643	}
2644
2645	static bool IsConstNonVolatile(QualType T) {
2646	Qualifiers Quals = T.getQualifiers();
2647	return Quals.hasConst() && !Quals.hasVolatile();
2648	}
2649
2650	/// Get the base index of the given base class within an APValue representing
2651	/// the given derived class.
2652	static unsigned getBaseIndex(const CXXRecordDecl *Derived,
2653	const CXXRecordDecl *Base) {
2654	Base = Base->getCanonicalDecl();
2655	unsigned Index = 0;
2656	for (CXXRecordDecl::base_class_const_iterator I = Derived->bases_begin(),
2657	E = Derived->bases_end(); I != E; ++I, ++Index) {
2658	if (I->getType()->getAsCXXRecordDecl()->getCanonicalDecl() == Base)
2659	return Index;
2660	}
2661
2662	llvm_unreachable("base class missing from derived class's bases list");
2663	}
2664
2665	/// Extract the value of a character from a string literal.
2666	static APSInt extractStringLiteralCharacter(EvalInfo &Info, const Expr *Lit,
2667	uint64_t Index) {
2668	// FIXME: Support MakeStringConstant
2669	if (const auto *ObjCEnc = dyn_cast<ObjCEncodeExpr>(Lit)) {
2670	std::string Str;
2671	Info.Ctx.getObjCEncodingForType(ObjCEnc->getEncodedType(), Str);
2672	(0) . __assert_fail ("Index <= Str.size() && \"Index too large\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 2672, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(Index <= Str.size() && "Index too large");
2673	return APSInt::getUnsigned(Str.c_str()[Index]);
2674	}
2675
2676	if (auto PE = dyn_cast<PredefinedExpr>(Lit))
2677	Lit = PE->getFunctionName();
2678	const StringLiteral *S = cast<StringLiteral>(Lit);
2679	const ConstantArrayType *CAT =
2680	Info.Ctx.getAsConstantArrayType(S->getType());
2681	(0) . __assert_fail ("CAT && \"string literal isn't an array\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 2681, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(CAT && "string literal isn't an array");
2682	QualType CharType = CAT->getElementType();
2683	(0) . __assert_fail ("CharType->isIntegerType() && \"unexpected character type\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 2683, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(CharType->isIntegerType() && "unexpected character type");
2684
2685	APSInt Value(S->getCharByteWidth() * Info.Ctx.getCharWidth(),
2686	CharType->isUnsignedIntegerType());
2687	if (Index < S->getLength())
2688	Value = S->getCodeUnit(Index);
2689	return Value;
2690	}
2691
2692	// Expand a string literal into an array of characters.
2693	//
2694	// FIXME: This is inefficient; we should probably introduce something similar
2695	// to the LLVM ConstantDataArray to make this cheaper.
2696	static void expandStringLiteral(EvalInfo &Info, const StringLiteral *S,
2697	APValue &Result) {
2698	const ConstantArrayType *CAT =
2699	Info.Ctx.getAsConstantArrayType(S->getType());
2700	(0) . __assert_fail ("CAT && \"string literal isn't an array\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 2700, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(CAT && "string literal isn't an array");
2701	QualType CharType = CAT->getElementType();
2702	(0) . __assert_fail ("CharType->isIntegerType() && \"unexpected character type\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 2702, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(CharType->isIntegerType() && "unexpected character type");
2703
2704	unsigned Elts = CAT->getSize().getZExtValue();
2705	Result = APValue(APValue::UninitArray(),
2706	std::min(S->getLength(), Elts), Elts);
2707	APSInt Value(S->getCharByteWidth() * Info.Ctx.getCharWidth(),
2708	CharType->isUnsignedIntegerType());
2709	if (Result.hasArrayFiller())
2710	Result.getArrayFiller() = APValue(Value);
2711	for (unsigned I = 0, N = Result.getArrayInitializedElts(); I != N; ++I) {
2712	Value = S->getCodeUnit(I);
2713	Result.getArrayInitializedElt(I) = APValue(Value);
2714	}
2715	}
2716
2717	// Expand an array so that it has more than Index filled elements.
2718	static void expandArray(APValue &Array, unsigned Index) {
2719	unsigned Size = Array.getArraySize();
2720	assert(Index < Size);
2721
2722	// Always at least double the number of elements for which we store a value.
2723	unsigned OldElts = Array.getArrayInitializedElts();
2724	unsigned NewElts = std::max(Index+1, OldElts * 2);
2725	NewElts = std::min(Size, std::max(NewElts, 8u));
2726
2727	// Copy the data across.
2728	APValue NewValue(APValue::UninitArray(), NewElts, Size);
2729	for (unsigned I = 0; I != OldElts; ++I)
2730	NewValue.getArrayInitializedElt(I).swap(Array.getArrayInitializedElt(I));
2731	for (unsigned I = OldElts; I != NewElts; ++I)
2732	NewValue.getArrayInitializedElt(I) = Array.getArrayFiller();
2733	if (NewValue.hasArrayFiller())
2734	NewValue.getArrayFiller() = Array.getArrayFiller();
2735	Array.swap(NewValue);
2736	}
2737
2738	/// Determine whether a type would actually be read by an lvalue-to-rvalue
2739	/// conversion. If it's of class type, we may assume that the copy operation
2740	/// is trivial. Note that this is never true for a union type with fields
2741	/// (because the copy always "reads" the active member) and always true for
2742	/// a non-class type.
2743	static bool isReadByLvalueToRvalueConversion(QualType T) {
2744	CXXRecordDecl *RD = T->getBaseElementTypeUnsafe()->getAsCXXRecordDecl();
2745	if (!RD \|\| (RD->isUnion() && !RD->field_empty()))
2746	return true;
2747	if (RD->isEmpty())
2748	return false;
2749
2750	for (auto *Field : RD->fields())
2751	if (isReadByLvalueToRvalueConversion(Field->getType()))
2752	return true;
2753
2754	for (auto &BaseSpec : RD->bases())
2755	if (isReadByLvalueToRvalueConversion(BaseSpec.getType()))
2756	return true;
2757
2758	return false;
2759	}
2760
2761	/// Diagnose an attempt to read from any unreadable field within the specified
2762	/// type, which might be a class type.
2763	static bool diagnoseUnreadableFields(EvalInfo &Info, const Expr *E,
2764	QualType T) {
2765	CXXRecordDecl *RD = T->getBaseElementTypeUnsafe()->getAsCXXRecordDecl();
2766	if (!RD)
2767	return false;
2768
2769	if (!RD->hasMutableFields())
2770	return false;
2771
2772	for (auto *Field : RD->fields()) {
2773	// If we're actually going to read this field in some way, then it can't
2774	// be mutable. If we're in a union, then assigning to a mutable field
2775	// (even an empty one) can change the active member, so that's not OK.
2776	// FIXME: Add core issue number for the union case.
2777	if (Field->isMutable() &&
2778	(RD->isUnion() \|\| isReadByLvalueToRvalueConversion(Field->getType()))) {
2779	Info.FFDiag(E, diag::note_constexpr_ltor_mutable, 1) << Field;
2780	Info.Note(Field->getLocation(), diag::note_declared_at);
2781	return true;
2782	}
2783
2784	if (diagnoseUnreadableFields(Info, E, Field->getType()))
2785	return true;
2786	}
2787
2788	for (auto &BaseSpec : RD->bases())
2789	if (diagnoseUnreadableFields(Info, E, BaseSpec.getType()))
2790	return true;
2791
2792	// All mutable fields were empty, and thus not actually read.
2793	return false;
2794	}
2795
2796	namespace {
2797	/// A handle to a complete object (an object that is not a subobject of
2798	/// another object).
2799	struct CompleteObject {
2800	/// The value of the complete object.
2801	APValue *Value;
2802	/// The type of the complete object.
2803	QualType Type;
2804	bool LifetimeStartedInEvaluation;
2805
2806	CompleteObject() : Value(nullptr) {}
2807	CompleteObject(APValue *Value, QualType Type,
2808	bool LifetimeStartedInEvaluation)
2809	: Value(Value), Type(Type),
2810	LifetimeStartedInEvaluation(LifetimeStartedInEvaluation) {
2811	(0) . __assert_fail ("Value && \"missing value for complete object\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 2811, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(Value && "missing value for complete object");
2812	}
2813
2814	explicit operator bool() const { return Value; }
2815	};
2816	} // end anonymous namespace
2817
2818	/// Find the designated sub-object of an rvalue.
2819	template<typename SubobjectHandler>
2820	typename SubobjectHandler::result_type
2821	findSubobject(EvalInfo &Info, const Expr *E, const CompleteObject &Obj,
2822	const SubobjectDesignator &Sub, SubobjectHandler &handler) {
2823	if (Sub.Invalid)
2824	// A diagnostic will have already been produced.
2825	return handler.failed();
2826	if (Sub.isOnePastTheEnd() \|\| Sub.isMostDerivedAnUnsizedArray()) {
2827	if (Info.getLangOpts().CPlusPlus11)
2828	Info.FFDiag(E, Sub.isOnePastTheEnd()
2829	? diag::note_constexpr_access_past_end
2830	: diag::note_constexpr_access_unsized_array)
2831	<< handler.AccessKind;
2832	else
2833	Info.FFDiag(E);
2834	return handler.failed();
2835	}
2836
2837	APValue *O = Obj.Value;
2838	QualType ObjType = Obj.Type;
2839	const FieldDecl *LastField = nullptr;
2840	const bool MayReadMutableMembers =
2841	Obj.LifetimeStartedInEvaluation && Info.getLangOpts().CPlusPlus14;
2842
2843	// Walk the designator's path to find the subobject.
2844	for (unsigned I = 0, N = Sub.Entries.size(); /**/; ++I) {
2845	if (O->isUninit()) {
2846	if (!Info.checkingPotentialConstantExpression())
2847	Info.FFDiag(E, diag::note_constexpr_access_uninit) << handler.AccessKind;
2848	return handler.failed();
2849	}
2850
2851	if (I == N) {
2852	// If we are reading an object of class type, there may still be more
2853	// things we need to check: if there are any mutable subobjects, we
2854	// cannot perform this read. (This only happens when performing a trivial
2855	// copy or assignment.)
2856	if (ObjType->isRecordType() && handler.AccessKind == AK_Read &&
2857	!MayReadMutableMembers && diagnoseUnreadableFields(Info, E, ObjType))
2858	return handler.failed();
2859
2860	if (!handler.found(*O, ObjType))
2861	return false;
2862
2863	// If we modified a bit-field, truncate it to the right width.
2864	if (handler.AccessKind != AK_Read &&
2865	LastField && LastField->isBitField() &&
2866	!truncateBitfieldValue(Info, E, *O, LastField))
2867	return false;
2868
2869	return true;
2870	}
2871
2872	LastField = nullptr;
2873	if (ObjType->isArrayType()) {
2874	// Next subobject is an array element.
2875	const ConstantArrayType *CAT = Info.Ctx.getAsConstantArrayType(ObjType);
2876	(0) . __assert_fail ("CAT && \"vla in literal type?\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 2876, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(CAT && "vla in literal type?");
2877	uint64_t Index = Sub.Entries[I].ArrayIndex;
2878	if (CAT->getSize().ule(Index)) {
2879	// Note, it should not be possible to form a pointer with a valid
2880	// designator which points more than one past the end of the array.
2881	if (Info.getLangOpts().CPlusPlus11)
2882	Info.FFDiag(E, diag::note_constexpr_access_past_end)
2883	<< handler.AccessKind;
2884	else
2885	Info.FFDiag(E);
2886	return handler.failed();
2887	}
2888
2889	ObjType = CAT->getElementType();
2890
2891	if (O->getArrayInitializedElts() > Index)
2892	O = &O->getArrayInitializedElt(Index);
2893	else if (handler.AccessKind != AK_Read) {
2894	expandArray(*O, Index);
2895	O = &O->getArrayInitializedElt(Index);
2896	} else
2897	O = &O->getArrayFiller();
2898	} else if (ObjType->isAnyComplexType()) {
2899	// Next subobject is a complex number.
2900	uint64_t Index = Sub.Entries[I].ArrayIndex;
2901	if (Index > 1) {
2902	if (Info.getLangOpts().CPlusPlus11)
2903	Info.FFDiag(E, diag::note_constexpr_access_past_end)
2904	<< handler.AccessKind;
2905	else
2906	Info.FFDiag(E);
2907	return handler.failed();
2908	}
2909
2910	bool WasConstQualified = ObjType.isConstQualified();
2911	ObjType = ObjType->castAs<ComplexType>()->getElementType();
2912	if (WasConstQualified)
2913	ObjType.addConst();
2914
2915	(0) . __assert_fail ("I == N - 1 && \"extracting subobject of scalar?\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 2915, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(I == N - 1 && "extracting subobject of scalar?");
2916	if (O->isComplexInt()) {
2917	return handler.found(Index ? O->getComplexIntImag()
2918	: O->getComplexIntReal(), ObjType);
2919	} else {
2920	isComplexFloat()", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 2920, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(O->isComplexFloat());
2921	return handler.found(Index ? O->getComplexFloatImag()
2922	: O->getComplexFloatReal(), ObjType);
2923	}
2924	} else if (const FieldDecl *Field = getAsField(Sub.Entries[I])) {
2925	// In C++14 onwards, it is permitted to read a mutable member whose
2926	// lifetime began within the evaluation.
2927	// FIXME: Should we also allow this in C++11?
2928	if (Field->isMutable() && handler.AccessKind == AK_Read &&
2929	!MayReadMutableMembers) {
2930	Info.FFDiag(E, diag::note_constexpr_ltor_mutable, 1)
2931	<< Field;
2932	Info.Note(Field->getLocation(), diag::note_declared_at);
2933	return handler.failed();
2934	}
2935
2936	// Next subobject is a class, struct or union field.
2937	RecordDecl *RD = ObjType->castAs<RecordType>()->getDecl();
2938	if (RD->isUnion()) {
2939	const FieldDecl *UnionField = O->getUnionField();
2940	if (!UnionField \|\|
2941	UnionField->getCanonicalDecl() != Field->getCanonicalDecl()) {
2942	Info.FFDiag(E, diag::note_constexpr_access_inactive_union_member)
2943	<< handler.AccessKind << Field << !UnionField << UnionField;
2944	return handler.failed();
2945	}
2946	O = &O->getUnionValue();
2947	} else
2948	O = &O->getStructField(Field->getFieldIndex());
2949
2950	bool WasConstQualified = ObjType.isConstQualified();
2951	ObjType = Field->getType();
2952	if (WasConstQualified && !Field->isMutable())
2953	ObjType.addConst();
2954
2955	if (ObjType.isVolatileQualified()) {
2956	if (Info.getLangOpts().CPlusPlus) {
2957	// FIXME: Include a description of the path to the volatile subobject.
2958	Info.FFDiag(E, diag::note_constexpr_access_volatile_obj, 1)
2959	<< handler.AccessKind << 2 << Field;
2960	Info.Note(Field->getLocation(), diag::note_declared_at);
2961	} else {
2962	Info.FFDiag(E, diag::note_invalid_subexpr_in_const_expr);
2963	}
2964	return handler.failed();
2965	}
2966
2967	LastField = Field;
2968	} else {
2969	// Next subobject is a base class.
2970	const CXXRecordDecl *Derived = ObjType->getAsCXXRecordDecl();
2971	const CXXRecordDecl *Base = getAsBaseClass(Sub.Entries[I]);
2972	O = &O->getStructBase(getBaseIndex(Derived, Base));
2973
2974	bool WasConstQualified = ObjType.isConstQualified();
2975	ObjType = Info.Ctx.getRecordType(Base);
2976	if (WasConstQualified)
2977	ObjType.addConst();
2978	}
2979	}
2980	}
2981
2982	namespace {
2983	struct ExtractSubobjectHandler {
2984	EvalInfo &Info;
2985	APValue &Result;
2986
2987	static const AccessKinds AccessKind = AK_Read;
2988
2989	typedef bool result_type;
2990	bool failed() { return false; }
2991	bool found(APValue &Subobj, QualType SubobjType) {
2992	Result = Subobj;
2993	return true;
2994	}
2995	bool found(APSInt &Value, QualType SubobjType) {
2996	Result = APValue(Value);
2997	return true;
2998	}
2999	bool found(APFloat &Value, QualType SubobjType) {
3000	Result = APValue(Value);
3001	return true;
3002	}
3003	};
3004	} // end anonymous namespace
3005
3006	const AccessKinds ExtractSubobjectHandler::AccessKind;
3007
3008	/// Extract the designated sub-object of an rvalue.
3009	static bool extractSubobject(EvalInfo &Info, const Expr *E,
3010	const CompleteObject &Obj,
3011	const SubobjectDesignator &Sub,
3012	APValue &Result) {
3013	ExtractSubobjectHandler Handler = { Info, Result };
3014	return findSubobject(Info, E, Obj, Sub, Handler);
3015	}
3016
3017	namespace {
3018	struct ModifySubobjectHandler {
3019	EvalInfo &Info;
3020	APValue &NewVal;
3021	const Expr *E;
3022
3023	typedef bool result_type;
3024	static const AccessKinds AccessKind = AK_Assign;
3025
3026	bool checkConst(QualType QT) {
3027	// Assigning to a const object has undefined behavior.
3028	if (QT.isConstQualified()) {
3029	Info.FFDiag(E, diag::note_constexpr_modify_const_type) << QT;
3030	return false;
3031	}
3032	return true;
3033	}
3034
3035	bool failed() { return false; }
3036	bool found(APValue &Subobj, QualType SubobjType) {
3037	if (!checkConst(SubobjType))
3038	return false;
3039	// We've been given ownership of NewVal, so just swap it in.
3040	Subobj.swap(NewVal);
3041	return true;
3042	}
3043	bool found(APSInt &Value, QualType SubobjType) {
3044	if (!checkConst(SubobjType))
3045	return false;
3046	if (!NewVal.isInt()) {
3047	// Maybe trying to write a cast pointer value into a complex?
3048	Info.FFDiag(E);
3049	return false;
3050	}
3051	Value = NewVal.getInt();
3052	return true;
3053	}
3054	bool found(APFloat &Value, QualType SubobjType) {
3055	if (!checkConst(SubobjType))
3056	return false;
3057	Value = NewVal.getFloat();
3058	return true;
3059	}
3060	};
3061	} // end anonymous namespace
3062
3063	const AccessKinds ModifySubobjectHandler::AccessKind;
3064
3065	/// Update the designated sub-object of an rvalue to the given value.
3066	static bool modifySubobject(EvalInfo &Info, const Expr *E,
3067	const CompleteObject &Obj,
3068	const SubobjectDesignator &Sub,
3069	APValue &NewVal) {
3070	ModifySubobjectHandler Handler = { Info, NewVal, E };
3071	return findSubobject(Info, E, Obj, Sub, Handler);
3072	}
3073
3074	/// Find the position where two subobject designators diverge, or equivalently
3075	/// the length of the common initial subsequence.
3076	static unsigned FindDesignatorMismatch(QualType ObjType,
3077	const SubobjectDesignator &A,
3078	const SubobjectDesignator &B,
3079	bool &WasArrayIndex) {
3080	unsigned I = 0, N = std::min(A.Entries.size(), B.Entries.size());
3081	for (/**/; I != N; ++I) {
3082	if (!ObjType.isNull() &&
3083	(ObjType->isArrayType() \|\| ObjType->isAnyComplexType())) {
3084	// Next subobject is an array element.
3085	if (A.Entries[I].ArrayIndex != B.Entries[I].ArrayIndex) {
3086	WasArrayIndex = true;
3087	return I;
3088	}
3089	if (ObjType->isAnyComplexType())
3090	ObjType = ObjType->castAs<ComplexType>()->getElementType();
3091	else
3092	ObjType = ObjType->castAsArrayTypeUnsafe()->getElementType();
3093	} else {
3094	if (A.Entries[I].BaseOrMember != B.Entries[I].BaseOrMember) {
3095	WasArrayIndex = false;
3096	return I;
3097	}
3098	if (const FieldDecl *FD = getAsField(A.Entries[I]))
3099	// Next subobject is a field.
3100	ObjType = FD->getType();
3101	else
3102	// Next subobject is a base class.
3103	ObjType = QualType();
3104	}
3105	}
3106	WasArrayIndex = false;
3107	return I;
3108	}
3109
3110	/// Determine whether the given subobject designators refer to elements of the
3111	/// same array object.
3112	static bool AreElementsOfSameArray(QualType ObjType,
3113	const SubobjectDesignator &A,
3114	const SubobjectDesignator &B) {
3115	if (A.Entries.size() != B.Entries.size())
3116	return false;
3117
3118	bool IsArray = A.MostDerivedIsArrayElement;
3119	if (IsArray && A.MostDerivedPathLength != A.Entries.size())
3120	// A is a subobject of the array element.
3121	return false;
3122
3123	// If A (and B) designates an array element, the last entry will be the array
3124	// index. That doesn't have to match. Otherwise, we're in the 'implicit array
3125	// of length 1' case, and the entire path must match.
3126	bool WasArrayIndex;
3127	unsigned CommonLength = FindDesignatorMismatch(ObjType, A, B, WasArrayIndex);
3128	return CommonLength >= A.Entries.size() - IsArray;
3129	}
3130
3131	/// Find the complete object to which an LValue refers.
3132	static CompleteObject findCompleteObject(EvalInfo &Info, const Expr *E,
3133	AccessKinds AK, const LValue &LVal,
3134	QualType LValType) {
3135	if (!LVal.Base) {
3136	Info.FFDiag(E, diag::note_constexpr_access_null) << AK;
3137	return CompleteObject();
3138	}
3139
3140	CallStackFrame *Frame = nullptr;
3141	if (LVal.getLValueCallIndex()) {
3142	Frame = Info.getCallFrame(LVal.getLValueCallIndex());
3143	if (!Frame) {
3144	Info.FFDiag(E, diag::note_constexpr_lifetime_ended, 1)
3145	<< AK << LVal.Base.is<const ValueDecl*>();
3146	NoteLValueLocation(Info, LVal.Base);
3147	return CompleteObject();
3148	}
3149	}
3150
3151	// C++11 DR1311: An lvalue-to-rvalue conversion on a volatile-qualified type
3152	// is not a constant expression (even if the object is non-volatile). We also
3153	// apply this rule to C++98, in order to conform to the expected 'volatile'
3154	// semantics.
3155	if (LValType.isVolatileQualified()) {
3156	if (Info.getLangOpts().CPlusPlus)
3157	Info.FFDiag(E, diag::note_constexpr_access_volatile_type)
3158	<< AK << LValType;
3159	else
3160	Info.FFDiag(E);
3161	return CompleteObject();
3162	}
3163
3164	// Compute value storage location and type of base object.
3165	APValue *BaseVal = nullptr;
3166	QualType BaseType = getType(LVal.Base);
3167	bool LifetimeStartedInEvaluation = Frame;
3168
3169	if (const ValueDecl D = LVal.Base.dyn_cast<const ValueDecl>()) {
3170	// In C++98, const, non-volatile integers initialized with ICEs are ICEs.
3171	// In C++11, constexpr, non-volatile variables initialized with constant
3172	// expressions are constant expressions too. Inside constexpr functions,
3173	// parameters are constant expressions even if they're non-const.
3174	// In C++1y, objects local to a constant expression (those with a Frame) are
3175	// both readable and writable inside constant expressions.
3176	// In C, such things can also be folded, although they are not ICEs.
3177	const VarDecl *VD = dyn_cast<VarDecl>(D);
3178	if (VD) {
3179	if (const VarDecl *VDef = VD->getDefinition(Info.Ctx))
3180	VD = VDef;
3181	}
3182	if (!VD \|\| VD->isInvalidDecl()) {
3183	Info.FFDiag(E);
3184	return CompleteObject();
3185	}
3186
3187	// Accesses of volatile-qualified objects are not allowed.
3188	if (BaseType.isVolatileQualified()) {
3189	if (Info.getLangOpts().CPlusPlus) {
3190	Info.FFDiag(E, diag::note_constexpr_access_volatile_obj, 1)
3191	<< AK << 1 << VD;
3192	Info.Note(VD->getLocation(), diag::note_declared_at);
3193	} else {
3194	Info.FFDiag(E);
3195	}
3196	return CompleteObject();
3197	}
3198
3199	// Unless we're looking at a local variable or argument in a constexpr call,
3200	// the variable we're reading must be const.
3201	if (!Frame) {
3202	if (Info.getLangOpts().CPlusPlus14 &&
3203	VD == Info.EvaluatingDecl.dyn_cast<const ValueDecl *>()) {
3204	// OK, we can read and modify an object if we're in the process of
3205	// evaluating its initializer, because its lifetime began in this
3206	// evaluation.
3207	} else if (AK != AK_Read) {
3208	// All the remaining cases only permit reading.
3209	Info.FFDiag(E, diag::note_constexpr_modify_global);
3210	return CompleteObject();
3211	} else if (VD->isConstexpr()) {
3212	// OK, we can read this variable.
3213	} else if (BaseType->isIntegralOrEnumerationType()) {
3214	// In OpenCL if a variable is in constant address space it is a const value.
3215	if (!(BaseType.isConstQualified() \|\|
3216	(Info.getLangOpts().OpenCL &&
3217	BaseType.getAddressSpace() == LangAS::opencl_constant))) {
3218	if (Info.getLangOpts().CPlusPlus) {
3219	Info.FFDiag(E, diag::note_constexpr_ltor_non_const_int, 1) << VD;
3220	Info.Note(VD->getLocation(), diag::note_declared_at);
3221	} else {
3222	Info.FFDiag(E);
3223	}
3224	return CompleteObject();
3225	}
3226	} else if (BaseType->isFloatingType() && BaseType.isConstQualified()) {
3227	// We support folding of const floating-point types, in order to make
3228	// static const data members of such types (supported as an extension)
3229	// more useful.
3230	if (Info.getLangOpts().CPlusPlus11) {
3231	Info.CCEDiag(E, diag::note_constexpr_ltor_non_constexpr, 1) << VD;
3232	Info.Note(VD->getLocation(), diag::note_declared_at);
3233	} else {
3234	Info.CCEDiag(E);
3235	}
3236	} else if (BaseType.isConstQualified() && VD->hasDefinition(Info.Ctx)) {
3237	Info.CCEDiag(E, diag::note_constexpr_ltor_non_constexpr) << VD;
3238	// Keep evaluating to see what we can do.
3239	} else {
3240	// FIXME: Allow folding of values of any literal type in all languages.
3241	if (Info.checkingPotentialConstantExpression() &&
3242	VD->getType().isConstQualified() && !VD->hasDefinition(Info.Ctx)) {
3243	// The definition of this variable could be constexpr. We can't
3244	// access it right now, but may be able to in future.
3245	} else if (Info.getLangOpts().CPlusPlus11) {
3246	Info.FFDiag(E, diag::note_constexpr_ltor_non_constexpr, 1) << VD;
3247	Info.Note(VD->getLocation(), diag::note_declared_at);
3248	} else {
3249	Info.FFDiag(E);
3250	}
3251	return CompleteObject();
3252	}
3253	}
3254
3255	if (!evaluateVarDeclInit(Info, E, VD, Frame, BaseVal, &LVal))
3256	return CompleteObject();
3257	} else {
3258	const Expr Base = LVal.Base.dyn_cast<const Expr>();
3259
3260	if (!Frame) {
3261	if (const MaterializeTemporaryExpr *MTE =
3262	dyn_cast<MaterializeTemporaryExpr>(Base)) {
3263	(0) . __assert_fail ("MTE->getStorageDuration() == SD_Static && \"should have a frame for a non-global materialized temporary\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 3264, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(MTE->getStorageDuration() == SD_Static &&
3264	(0) . __assert_fail ("MTE->getStorageDuration() == SD_Static && \"should have a frame for a non-global materialized temporary\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 3264, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true"> "should have a frame for a non-global materialized temporary");
3265
3266	// Per C++1y [expr.const]p2:
3267	// an lvalue-to-rvalue conversion [is not allowed unless it applies to]
3268	// - a [...] glvalue of integral or enumeration type that refers to
3269	// a non-volatile const object [...]
3270	// [...]
3271	// - a [...] glvalue of literal type that refers to a non-volatile
3272	// object whose lifetime began within the evaluation of e.
3273	//
3274	// C++11 misses the 'began within the evaluation of e' check and
3275	// instead allows all temporaries, including things like:
3276	// int &&r = 1;
3277	// int x = ++r;
3278	// constexpr int k = r;
3279	// Therefore we use the C++14 rules in C++11 too.
3280	const ValueDecl VD = Info.EvaluatingDecl.dyn_cast<const ValueDecl>();
3281	const ValueDecl *ED = MTE->getExtendingDecl();
3282	if (!(BaseType.isConstQualified() &&
3283	BaseType->isIntegralOrEnumerationType()) &&
3284	!(VD && VD->getCanonicalDecl() == ED->getCanonicalDecl())) {
3285	Info.FFDiag(E, diag::note_constexpr_access_static_temporary, 1) << AK;
3286	Info.Note(MTE->getExprLoc(), diag::note_constexpr_temporary_here);
3287	return CompleteObject();
3288	}
3289
3290	BaseVal = Info.Ctx.getMaterializedTemporaryValue(MTE, false);
3291	(0) . __assert_fail ("BaseVal && \"got reference to unevaluated temporary\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 3291, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(BaseVal && "got reference to unevaluated temporary");
3292	LifetimeStartedInEvaluation = true;
3293	} else {
3294	Info.FFDiag(E);
3295	return CompleteObject();
3296	}
3297	} else {
3298	BaseVal = Frame->getTemporary(Base, LVal.Base.getVersion());
3299	(0) . __assert_fail ("BaseVal && \"missing value for temporary\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 3299, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(BaseVal && "missing value for temporary");
3300	}
3301
3302	// Volatile temporary objects cannot be accessed in constant expressions.
3303	if (BaseType.isVolatileQualified()) {
3304	if (Info.getLangOpts().CPlusPlus) {
3305	Info.FFDiag(E, diag::note_constexpr_access_volatile_obj, 1)
3306	<< AK << 0;
3307	Info.Note(Base->getExprLoc(), diag::note_constexpr_temporary_here);
3308	} else {
3309	Info.FFDiag(E);
3310	}
3311	return CompleteObject();
3312	}
3313	}
3314
3315	// During the construction of an object, it is not yet 'const'.
3316	// FIXME: This doesn't do quite the right thing for const subobjects of the
3317	// object under construction.
3318	if (Info.isEvaluatingConstructor(LVal.getLValueBase(),
3319	LVal.getLValueCallIndex(),
3320	LVal.getLValueVersion())) {
3321	BaseType = Info.Ctx.getCanonicalType(BaseType);
3322	BaseType.removeLocalConst();
3323	LifetimeStartedInEvaluation = true;
3324	}
3325
3326	// In C++14, we can't safely access any mutable state when we might be
3327	// evaluating after an unmodeled side effect.
3328	//
3329	// FIXME: Not all local state is mutable. Allow local constant subobjects
3330	// to be read here (but take care with 'mutable' fields).
3331	if ((Frame && Info.getLangOpts().CPlusPlus14 &&
3332	Info.EvalStatus.HasSideEffects) \|\|
3333	(AK != AK_Read && Info.IsSpeculativelyEvaluating))
3334	return CompleteObject();
3335
3336	return CompleteObject(BaseVal, BaseType, LifetimeStartedInEvaluation);
3337	}
3338
3339	/// Perform an lvalue-to-rvalue conversion on the given glvalue. This
3340	/// can also be used for 'lvalue-to-lvalue' conversions for looking up the
3341	/// glvalue referred to by an entity of reference type.
3342	///
3343	/// \param Info - Information about the ongoing evaluation.
3344	/// \param Conv - The expression for which we are performing the conversion.
3345	/// Used for diagnostics.
3346	/// \param Type - The type of the glvalue (before stripping cv-qualifiers in the
3347	/// case of a non-class type).
3348	/// \param LVal - The glvalue on which we are attempting to perform this action.
3349	/// \param RVal - The produced value will be placed here.
3350	static bool handleLValueToRValueConversion(EvalInfo &Info, const Expr *Conv,
3351	QualType Type,
3352	const LValue &LVal, APValue &RVal) {
3353	if (LVal.Designator.Invalid)
3354	return false;
3355
3356	// Check for special cases where there is no existing APValue to look at.
3357	const Expr Base = LVal.Base.dyn_cast<const Expr>();
3358	if (Base && !LVal.getLValueCallIndex() && !Type.isVolatileQualified()) {
3359	if (const CompoundLiteralExpr *CLE = dyn_cast<CompoundLiteralExpr>(Base)) {
3360	// In C99, a CompoundLiteralExpr is an lvalue, and we defer evaluating the
3361	// initializer until now for such expressions. Such an expression can't be
3362	// an ICE in C, so this only matters for fold.
3363	if (Type.isVolatileQualified()) {
3364	Info.FFDiag(Conv);
3365	return false;
3366	}
3367	APValue Lit;
3368	if (!Evaluate(Lit, Info, CLE->getInitializer()))
3369	return false;
3370	CompleteObject LitObj(&Lit, Base->getType(), false);
3371	return extractSubobject(Info, Conv, LitObj, LVal.Designator, RVal);
3372	} else if (isa<StringLiteral>(Base) \|\| isa<PredefinedExpr>(Base)) {
3373	// Special-case character extraction so we don't have to construct an
3374	// APValue for the whole string.
3375	(0) . __assert_fail ("LVal.Designator.Entries.size() <= 1 && \"Can only read characters from string literals\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 3376, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(LVal.Designator.Entries.size() <= 1 &&
3376	(0) . __assert_fail ("LVal.Designator.Entries.size() <= 1 && \"Can only read characters from string literals\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 3376, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true"> "Can only read characters from string literals");
3377	if (LVal.Designator.Entries.empty()) {
3378	// Fail for now for LValue to RValue conversion of an array.
3379	// (This shouldn't show up in C/C++, but it could be triggered by a
3380	// weird EvaluateAsRValue call from a tool.)
3381	Info.FFDiag(Conv);
3382	return false;
3383	}
3384	if (LVal.Designator.isOnePastTheEnd()) {
3385	if (Info.getLangOpts().CPlusPlus11)
3386	Info.FFDiag(Conv, diag::note_constexpr_access_past_end) << AK_Read;
3387	else
3388	Info.FFDiag(Conv);
3389	return false;
3390	}
3391	uint64_t CharIndex = LVal.Designator.Entries[0].ArrayIndex;
3392	RVal = APValue(extractStringLiteralCharacter(Info, Base, CharIndex));
3393	return true;
3394	}
3395	}
3396
3397	CompleteObject Obj = findCompleteObject(Info, Conv, AK_Read, LVal, Type);
3398	return Obj && extractSubobject(Info, Conv, Obj, LVal.Designator, RVal);
3399	}
3400
3401	/// Perform an assignment of Val to LVal. Takes ownership of Val.
3402	static bool handleAssignment(EvalInfo &Info, const Expr *E, const LValue &LVal,
3403	QualType LValType, APValue &Val) {
3404	if (LVal.Designator.Invalid)
3405	return false;
3406
3407	if (!Info.getLangOpts().CPlusPlus14) {
3408	Info.FFDiag(E);
3409	return false;
3410	}
3411
3412	CompleteObject Obj = findCompleteObject(Info, E, AK_Assign, LVal, LValType);
3413	return Obj && modifySubobject(Info, E, Obj, LVal.Designator, Val);
3414	}
3415
3416	namespace {
3417	struct CompoundAssignSubobjectHandler {
3418	EvalInfo &Info;
3419	const Expr *E;
3420	QualType PromotedLHSType;
3421	BinaryOperatorKind Opcode;
3422	const APValue &RHS;
3423
3424	static const AccessKinds AccessKind = AK_Assign;
3425
3426	typedef bool result_type;
3427
3428	bool checkConst(QualType QT) {
3429	// Assigning to a const object has undefined behavior.
3430	if (QT.isConstQualified()) {
3431	Info.FFDiag(E, diag::note_constexpr_modify_const_type) << QT;
3432	return false;
3433	}
3434	return true;
3435	}
3436
3437	bool failed() { return false; }
3438	bool found(APValue &Subobj, QualType SubobjType) {
3439	switch (Subobj.getKind()) {
3440	case APValue::Int:
3441	return found(Subobj.getInt(), SubobjType);
3442	case APValue::Float:
3443	return found(Subobj.getFloat(), SubobjType);
3444	case APValue::ComplexInt:
3445	case APValue::ComplexFloat:
3446	// FIXME: Implement complex compound assignment.
3447	Info.FFDiag(E);
3448	return false;
3449	case APValue::LValue:
3450	return foundPointer(Subobj, SubobjType);
3451	default:
3452	// FIXME: can this happen?
3453	Info.FFDiag(E);
3454	return false;
3455	}
3456	}
3457	bool found(APSInt &Value, QualType SubobjType) {
3458	if (!checkConst(SubobjType))
3459	return false;
3460
3461	if (!SubobjType->isIntegerType()) {
3462	// We don't support compound assignment on integer-cast-to-pointer
3463	// values.
3464	Info.FFDiag(E);
3465	return false;
3466	}
3467
3468	if (RHS.isInt()) {
3469	APSInt LHS =
3470	HandleIntToIntCast(Info, E, PromotedLHSType, SubobjType, Value);
3471	if (!handleIntIntBinOp(Info, E, LHS, Opcode, RHS.getInt(), LHS))
3472	return false;
3473	Value = HandleIntToIntCast(Info, E, SubobjType, PromotedLHSType, LHS);
3474	return true;
3475	} else if (RHS.isFloat()) {
3476	APFloat FValue(0.0);
3477	return HandleIntToFloatCast(Info, E, SubobjType, Value, PromotedLHSType,
3478	FValue) &&
3479	handleFloatFloatBinOp(Info, E, FValue, Opcode, RHS.getFloat()) &&
3480	HandleFloatToIntCast(Info, E, PromotedLHSType, FValue, SubobjType,
3481	Value);
3482	}
3483
3484	Info.FFDiag(E);
3485	return false;
3486	}
3487	bool found(APFloat &Value, QualType SubobjType) {
3488	return checkConst(SubobjType) &&
3489	HandleFloatToFloatCast(Info, E, SubobjType, PromotedLHSType,
3490	Value) &&
3491	handleFloatFloatBinOp(Info, E, Value, Opcode, RHS.getFloat()) &&
3492	HandleFloatToFloatCast(Info, E, PromotedLHSType, SubobjType, Value);
3493	}
3494	bool foundPointer(APValue &Subobj, QualType SubobjType) {
3495	if (!checkConst(SubobjType))
3496	return false;
3497
3498	QualType PointeeType;
3499	if (const PointerType *PT = SubobjType->getAs<PointerType>())
3500	PointeeType = PT->getPointeeType();
3501
3502	if (PointeeType.isNull() \|\| !RHS.isInt() \|\|
3503	(Opcode != BO_Add && Opcode != BO_Sub)) {
3504	Info.FFDiag(E);
3505	return false;
3506	}
3507
3508	APSInt Offset = RHS.getInt();
3509	if (Opcode == BO_Sub)
3510	negateAsSigned(Offset);
3511
3512	LValue LVal;
3513	LVal.setFrom(Info.Ctx, Subobj);
3514	if (!HandleLValueArrayAdjustment(Info, E, LVal, PointeeType, Offset))
3515	return false;
3516	LVal.moveInto(Subobj);
3517	return true;
3518	}
3519	};
3520	} // end anonymous namespace
3521
3522	const AccessKinds CompoundAssignSubobjectHandler::AccessKind;
3523
3524	/// Perform a compound assignment of LVal <op>= RVal.
3525	static bool handleCompoundAssignment(
3526	EvalInfo &Info, const Expr *E,
3527	const LValue &LVal, QualType LValType, QualType PromotedLValType,
3528	BinaryOperatorKind Opcode, const APValue &RVal) {
3529	if (LVal.Designator.Invalid)
3530	return false;
3531
3532	if (!Info.getLangOpts().CPlusPlus14) {
3533	Info.FFDiag(E);
3534	return false;
3535	}
3536
3537	CompleteObject Obj = findCompleteObject(Info, E, AK_Assign, LVal, LValType);
3538	CompoundAssignSubobjectHandler Handler = { Info, E, PromotedLValType, Opcode,
3539	RVal };
3540	return Obj && findSubobject(Info, E, Obj, LVal.Designator, Handler);
3541	}
3542
3543	namespace {
3544	struct IncDecSubobjectHandler {
3545	EvalInfo &Info;
3546	const UnaryOperator *E;
3547	AccessKinds AccessKind;
3548	APValue *Old;
3549
3550	typedef bool result_type;
3551
3552	bool checkConst(QualType QT) {
3553	// Assigning to a const object has undefined behavior.
3554	if (QT.isConstQualified()) {
3555	Info.FFDiag(E, diag::note_constexpr_modify_const_type) << QT;
3556	return false;
3557	}
3558	return true;
3559	}
3560
3561	bool failed() { return false; }
3562	bool found(APValue &Subobj, QualType SubobjType) {
3563	// Stash the old value. Also clear Old, so we don't clobber it later
3564	// if we're post-incrementing a complex.
3565	if (Old) {
3566	*Old = Subobj;
3567	Old = nullptr;
3568	}
3569
3570	switch (Subobj.getKind()) {
3571	case APValue::Int:
3572	return found(Subobj.getInt(), SubobjType);
3573	case APValue::Float:
3574	return found(Subobj.getFloat(), SubobjType);
3575	case APValue::ComplexInt:
3576	return found(Subobj.getComplexIntReal(),
3577	SubobjType->castAs<ComplexType>()->getElementType()
3578	.withCVRQualifiers(SubobjType.getCVRQualifiers()));
3579	case APValue::ComplexFloat:
3580	return found(Subobj.getComplexFloatReal(),
3581	SubobjType->castAs<ComplexType>()->getElementType()
3582	.withCVRQualifiers(SubobjType.getCVRQualifiers()));
3583	case APValue::LValue:
3584	return foundPointer(Subobj, SubobjType);
3585	default:
3586	// FIXME: can this happen?
3587	Info.FFDiag(E);
3588	return false;
3589	}
3590	}
3591	bool found(APSInt &Value, QualType SubobjType) {
3592	if (!checkConst(SubobjType))
3593	return false;
3594
3595	if (!SubobjType->isIntegerType()) {
3596	// We don't support increment / decrement on integer-cast-to-pointer
3597	// values.
3598	Info.FFDiag(E);
3599	return false;
3600	}
3601
3602	if (Old) *Old = APValue(Value);
3603
3604	// bool arithmetic promotes to int, and the conversion back to bool
3605	// doesn't reduce mod 2^n, so special-case it.
3606	if (SubobjType->isBooleanType()) {
3607	if (AccessKind == AK_Increment)
3608	Value = 1;
3609	else
3610	Value = !Value;
3611	return true;
3612	}
3613
3614	bool WasNegative = Value.isNegative();
3615	if (AccessKind == AK_Increment) {
3616	++Value;
3617
3618	if (!WasNegative && Value.isNegative() && E->canOverflow()) {
3619	APSInt ActualValue(Value, /IsUnsigned/true);
3620	return HandleOverflow(Info, E, ActualValue, SubobjType);
3621	}
3622	} else {
3623	--Value;
3624
3625	if (WasNegative && !Value.isNegative() && E->canOverflow()) {
3626	unsigned BitWidth = Value.getBitWidth();
3627	APSInt ActualValue(Value.sext(BitWidth + 1), /IsUnsigned/false);
3628	ActualValue.setBit(BitWidth);
3629	return HandleOverflow(Info, E, ActualValue, SubobjType);
3630	}
3631	}
3632	return true;
3633	}
3634	bool found(APFloat &Value, QualType SubobjType) {
3635	if (!checkConst(SubobjType))
3636	return false;
3637
3638	if (Old) *Old = APValue(Value);
3639
3640	APFloat One(Value.getSemantics(), 1);
3641	if (AccessKind == AK_Increment)
3642	Value.add(One, APFloat::rmNearestTiesToEven);
3643	else
3644	Value.subtract(One, APFloat::rmNearestTiesToEven);
3645	return true;
3646	}
3647	bool foundPointer(APValue &Subobj, QualType SubobjType) {
3648	if (!checkConst(SubobjType))
3649	return false;
3650
3651	QualType PointeeType;
3652	if (const PointerType *PT = SubobjType->getAs<PointerType>())
3653	PointeeType = PT->getPointeeType();
3654	else {
3655	Info.FFDiag(E);
3656	return false;
3657	}
3658
3659	LValue LVal;
3660	LVal.setFrom(Info.Ctx, Subobj);
3661	if (!HandleLValueArrayAdjustment(Info, E, LVal, PointeeType,
3662	AccessKind == AK_Increment ? 1 : -1))
3663	return false;
3664	LVal.moveInto(Subobj);
3665	return true;
3666	}
3667	};
3668	} // end anonymous namespace
3669
3670	/// Perform an increment or decrement on LVal.
3671	static bool handleIncDec(EvalInfo &Info, const Expr *E, const LValue &LVal,
3672	QualType LValType, bool IsIncrement, APValue *Old) {
3673	if (LVal.Designator.Invalid)
3674	return false;
3675
3676	if (!Info.getLangOpts().CPlusPlus14) {
3677	Info.FFDiag(E);
3678	return false;
3679	}
3680
3681	AccessKinds AK = IsIncrement ? AK_Increment : AK_Decrement;
3682	CompleteObject Obj = findCompleteObject(Info, E, AK, LVal, LValType);
3683	IncDecSubobjectHandler Handler = {Info, cast<UnaryOperator>(E), AK, Old};
3684	return Obj && findSubobject(Info, E, Obj, LVal.Designator, Handler);
3685	}
3686
3687	/// Build an lvalue for the object argument of a member function call.
3688	static bool EvaluateObjectArgument(EvalInfo &Info, const Expr *Object,
3689	LValue &This) {
3690	if (Object->getType()->isPointerType())
3691	return EvaluatePointer(Object, This, Info);
3692
3693	if (Object->isGLValue())
3694	return EvaluateLValue(Object, This, Info);
3695
3696	if (Object->getType()->isLiteralType(Info.Ctx))
3697	return EvaluateTemporary(Object, This, Info);
3698
3699	Info.FFDiag(Object, diag::note_constexpr_nonliteral) << Object->getType();
3700	return false;
3701	}
3702
3703	/// HandleMemberPointerAccess - Evaluate a member access operation and build an
3704	/// lvalue referring to the result.
3705	///
3706	/// \param Info - Information about the ongoing evaluation.
3707	/// \param LV - An lvalue referring to the base of the member pointer.
3708	/// \param RHS - The member pointer expression.
3709	/// \param IncludeMember - Specifies whether the member itself is included in
3710	/// the resulting LValue subobject designator. This is not possible when
3711	/// creating a bound member function.
3712	/// \return The field or method declaration to which the member pointer refers,
3713	/// or 0 if evaluation fails.
3714	static const ValueDecl *HandleMemberPointerAccess(EvalInfo &Info,
3715	QualType LVType,
3716	LValue &LV,
3717	const Expr *RHS,
3718	bool IncludeMember = true) {
3719	MemberPtr MemPtr;
3720	if (!EvaluateMemberPointer(RHS, MemPtr, Info))
3721	return nullptr;
3722
3723	// C++11 [expr.mptr.oper]p6: If the second operand is the null pointer to
3724	// member value, the behavior is undefined.
3725	if (!MemPtr.getDecl()) {
3726	// FIXME: Specific diagnostic.
3727	Info.FFDiag(RHS);
3728	return nullptr;
3729	}
3730
3731	if (MemPtr.isDerivedMember()) {
3732	// This is a member of some derived class. Truncate LV appropriately.
3733	// The end of the derived-to-base path for the base object must match the
3734	// derived-to-base path for the member pointer.
3735	if (LV.Designator.MostDerivedPathLength + MemPtr.Path.size() >
3736	LV.Designator.Entries.size()) {
3737	Info.FFDiag(RHS);
3738	return nullptr;
3739	}
3740	unsigned PathLengthToMember =
3741	LV.Designator.Entries.size() - MemPtr.Path.size();
3742	for (unsigned I = 0, N = MemPtr.Path.size(); I != N; ++I) {
3743	const CXXRecordDecl *LVDecl = getAsBaseClass(
3744	LV.Designator.Entries[PathLengthToMember + I]);
3745	const CXXRecordDecl *MPDecl = MemPtr.Path[I];
3746	if (LVDecl->getCanonicalDecl() != MPDecl->getCanonicalDecl()) {
3747	Info.FFDiag(RHS);
3748	return nullptr;
3749	}
3750	}
3751
3752	// Truncate the lvalue to the appropriate derived class.
3753	if (!CastToDerivedClass(Info, RHS, LV, MemPtr.getContainingRecord(),
3754	PathLengthToMember))
3755	return nullptr;
3756	} else if (!MemPtr.Path.empty()) {
3757	// Extend the LValue path with the member pointer's path.
3758	LV.Designator.Entries.reserve(LV.Designator.Entries.size() +
3759	MemPtr.Path.size() + IncludeMember);
3760
3761	// Walk down to the appropriate base class.
3762	if (const PointerType *PT = LVType->getAs<PointerType>())
3763	LVType = PT->getPointeeType();
3764	const CXXRecordDecl *RD = LVType->getAsCXXRecordDecl();
3765	(0) . __assert_fail ("RD && \"member pointer access on non-class-type expression\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 3765, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(RD && "member pointer access on non-class-type expression");
3766	// The first class in the path is that of the lvalue.
3767	for (unsigned I = 1, N = MemPtr.Path.size(); I != N; ++I) {
3768	const CXXRecordDecl *Base = MemPtr.Path[N - I - 1];
3769	if (!HandleLValueDirectBase(Info, RHS, LV, RD, Base))
3770	return nullptr;
3771	RD = Base;
3772	}
3773	// Finally cast to the class containing the member.
3774	if (!HandleLValueDirectBase(Info, RHS, LV, RD,
3775	MemPtr.getContainingRecord()))
3776	return nullptr;
3777	}
3778
3779	// Add the member. Note that we cannot build bound member functions here.
3780	if (IncludeMember) {
3781	if (const FieldDecl *FD = dyn_cast<FieldDecl>(MemPtr.getDecl())) {
3782	if (!HandleLValueMember(Info, RHS, LV, FD))
3783	return nullptr;
3784	} else if (const IndirectFieldDecl *IFD =
3785	dyn_cast<IndirectFieldDecl>(MemPtr.getDecl())) {
3786	if (!HandleLValueIndirectMember(Info, RHS, LV, IFD))
3787	return nullptr;
3788	} else {
3789	llvm_unreachable("can't construct reference to bound member function");
3790	}
3791	}
3792
3793	return MemPtr.getDecl();
3794	}
3795
3796	static const ValueDecl *HandleMemberPointerAccess(EvalInfo &Info,
3797	const BinaryOperator *BO,
3798	LValue &LV,
3799	bool IncludeMember = true) {
3800	getOpcode() == BO_PtrMemD \|\| BO->getOpcode() == BO_PtrMemI", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 3800, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(BO->getOpcode() == BO_PtrMemD \|\| BO->getOpcode() == BO_PtrMemI);
3801
3802	if (!EvaluateObjectArgument(Info, BO->getLHS(), LV)) {
3803	if (Info.noteFailure()) {
3804	MemberPtr MemPtr;
3805	EvaluateMemberPointer(BO->getRHS(), MemPtr, Info);
3806	}
3807	return nullptr;
3808	}
3809
3810	return HandleMemberPointerAccess(Info, BO->getLHS()->getType(), LV,
3811	BO->getRHS(), IncludeMember);
3812	}
3813
3814	/// HandleBaseToDerivedCast - Apply the given base-to-derived cast operation on
3815	/// the provided lvalue, which currently refers to the base object.
3816	static bool HandleBaseToDerivedCast(EvalInfo &Info, const CastExpr *E,
3817	LValue &Result) {
3818	SubobjectDesignator &D = Result.Designator;
3819	if (D.Invalid \|\| !Result.checkNullPointer(Info, E, CSK_Derived))
3820	return false;
3821
3822	QualType TargetQT = E->getType();
3823	if (const PointerType *PT = TargetQT->getAs<PointerType>())
3824	TargetQT = PT->getPointeeType();
3825
3826	// Check this cast lands within the final derived-to-base subobject path.
3827	if (D.MostDerivedPathLength + E->path_size() > D.Entries.size()) {
3828	Info.CCEDiag(E, diag::note_constexpr_invalid_downcast)
3829	<< D.MostDerivedType << TargetQT;
3830	return false;
3831	}
3832
3833	// Check the type of the final cast. We don't need to check the path,
3834	// since a cast can only be formed if the path is unique.
3835	unsigned NewEntriesSize = D.Entries.size() - E->path_size();
3836	const CXXRecordDecl *TargetType = TargetQT->getAsCXXRecordDecl();
3837	const CXXRecordDecl *FinalType;
3838	if (NewEntriesSize == D.MostDerivedPathLength)
3839	FinalType = D.MostDerivedType->getAsCXXRecordDecl();
3840	else
3841	FinalType = getAsBaseClass(D.Entries[NewEntriesSize - 1]);
3842	if (FinalType->getCanonicalDecl() != TargetType->getCanonicalDecl()) {
3843	Info.CCEDiag(E, diag::note_constexpr_invalid_downcast)
3844	<< D.MostDerivedType << TargetQT;
3845	return false;
3846	}
3847
3848	// Truncate the lvalue to the appropriate derived class.
3849	return CastToDerivedClass(Info, E, Result, TargetType, NewEntriesSize);
3850	}
3851
3852	namespace {
3853	enum EvalStmtResult {
3854	/// Evaluation failed.
3855	ESR_Failed,
3856	/// Hit a 'return' statement.
3857	ESR_Returned,
3858	/// Evaluation succeeded.
3859	ESR_Succeeded,
3860	/// Hit a 'continue' statement.
3861	ESR_Continue,
3862	/// Hit a 'break' statement.
3863	ESR_Break,
3864	/// Still scanning for 'case' or 'default' statement.
3865	ESR_CaseNotFound
3866	};
3867	}
3868
3869	static bool EvaluateVarDecl(EvalInfo &Info, const VarDecl *VD) {
3870	// We don't need to evaluate the initializer for a static local.
3871	if (!VD->hasLocalStorage())
3872	return true;
3873
3874	LValue Result;
3875	APValue &Val = createTemporary(VD, true, Result, *Info.CurrentCall);
3876
3877	const Expr *InitE = VD->getInit();
3878	if (!InitE) {
3879	Info.FFDiag(VD->getBeginLoc(), diag::note_constexpr_uninitialized)
3880	<< false << VD->getType();
3881	Val = APValue();
3882	return false;
3883	}
3884
3885	if (InitE->isValueDependent())
3886	return false;
3887
3888	if (!EvaluateInPlace(Val, Info, Result, InitE)) {
3889	// Wipe out any partially-computed value, to allow tracking that this
3890	// evaluation failed.
3891	Val = APValue();
3892	return false;
3893	}
3894
3895	return true;
3896	}
3897
3898	static bool EvaluateDecl(EvalInfo &Info, const Decl *D) {
3899	bool OK = true;
3900
3901	if (const VarDecl *VD = dyn_cast<VarDecl>(D))
3902	OK &= EvaluateVarDecl(Info, VD);
3903
3904	if (const DecompositionDecl *DD = dyn_cast<DecompositionDecl>(D))
3905	for (auto *BD : DD->bindings())
3906	if (auto *VD = BD->getHoldingVar())
3907	OK &= EvaluateDecl(Info, VD);
3908
3909	return OK;
3910	}
3911
3912
3913	/// Evaluate a condition (either a variable declaration or an expression).
3914	static bool EvaluateCond(EvalInfo &Info, const VarDecl *CondDecl,
3915	const Expr *Cond, bool &Result) {
3916	FullExpressionRAII Scope(Info);
3917	if (CondDecl && !EvaluateDecl(Info, CondDecl))
3918	return false;
3919	return EvaluateAsBooleanCondition(Cond, Result, Info);
3920	}
3921
3922	namespace {
3923	/// A location where the result (returned value) of evaluating a
3924	/// statement should be stored.
3925	struct StmtResult {
3926	/// The APValue that should be filled in with the returned value.
3927	APValue &Value;
3928	/// The location containing the result, if any (used to support RVO).
3929	const LValue *Slot;
3930	};
3931
3932	struct TempVersionRAII {
3933	CallStackFrame &Frame;
3934
3935	TempVersionRAII(CallStackFrame &Frame) : Frame(Frame) {
3936	Frame.pushTempVersion();
3937	}
3938
3939	~TempVersionRAII() {
3940	Frame.popTempVersion();
3941	}
3942	};
3943
3944	}
3945
3946	static EvalStmtResult EvaluateStmt(StmtResult &Result, EvalInfo &Info,
3947	const Stmt *S,
3948	const SwitchCase *SC = nullptr);
3949
3950	/// Evaluate the body of a loop, and translate the result as appropriate.
3951	static EvalStmtResult EvaluateLoopBody(StmtResult &Result, EvalInfo &Info,
3952	const Stmt *Body,
3953	const SwitchCase *Case = nullptr) {
3954	BlockScopeRAII Scope(Info);
3955	switch (EvalStmtResult ESR = EvaluateStmt(Result, Info, Body, Case)) {
3956	case ESR_Break:
3957	return ESR_Succeeded;
3958	case ESR_Succeeded:
3959	case ESR_Continue:
3960	return ESR_Continue;
3961	case ESR_Failed:
3962	case ESR_Returned:
3963	case ESR_CaseNotFound:
3964	return ESR;
3965	}
3966	llvm_unreachable("Invalid EvalStmtResult!");
3967	}
3968
3969	/// Evaluate a switch statement.
3970	static EvalStmtResult EvaluateSwitch(StmtResult &Result, EvalInfo &Info,
3971	const SwitchStmt *SS) {
3972	BlockScopeRAII Scope(Info);
3973
3974	// Evaluate the switch condition.
3975	APSInt Value;
3976	{
3977	FullExpressionRAII Scope(Info);
3978	if (const Stmt *Init = SS->getInit()) {
3979	EvalStmtResult ESR = EvaluateStmt(Result, Info, Init);
3980	if (ESR != ESR_Succeeded)
3981	return ESR;
3982	}
3983	if (SS->getConditionVariable() &&
3984	!EvaluateDecl(Info, SS->getConditionVariable()))
3985	return ESR_Failed;
3986	if (!EvaluateInteger(SS->getCond(), Value, Info))
3987	return ESR_Failed;
3988	}
3989
3990	// Find the switch case corresponding to the value of the condition.
3991	// FIXME: Cache this lookup.
3992	const SwitchCase *Found = nullptr;
3993	for (const SwitchCase *SC = SS->getSwitchCaseList(); SC;
3994	SC = SC->getNextSwitchCase()) {
3995	if (isa<DefaultStmt>(SC)) {
3996	Found = SC;
3997	continue;
3998	}
3999
4000	const CaseStmt *CS = cast<CaseStmt>(SC);
4001	APSInt LHS = CS->getLHS()->EvaluateKnownConstInt(Info.Ctx);
4002	APSInt RHS = CS->getRHS() ? CS->getRHS()->EvaluateKnownConstInt(Info.Ctx)
4003	: LHS;
4004	if (LHS <= Value && Value <= RHS) {
4005	Found = SC;
4006	break;
4007	}
4008	}
4009
4010	if (!Found)
4011	return ESR_Succeeded;
4012
4013	// Search the switch body for the switch case and evaluate it from there.
4014	switch (EvalStmtResult ESR = EvaluateStmt(Result, Info, SS->getBody(), Found)) {
4015	case ESR_Break:
4016	return ESR_Succeeded;
4017	case ESR_Succeeded:
4018	case ESR_Continue:
4019	case ESR_Failed:
4020	case ESR_Returned:
4021	return ESR;
4022	case ESR_CaseNotFound:
4023	// This can only happen if the switch case is nested within a statement
4024	// expression. We have no intention of supporting that.
4025	Info.FFDiag(Found->getBeginLoc(),
4026	diag::note_constexpr_stmt_expr_unsupported);
4027	return ESR_Failed;
4028	}
4029	llvm_unreachable("Invalid EvalStmtResult!");
4030	}
4031
4032	// Evaluate a statement.
4033	static EvalStmtResult EvaluateStmt(StmtResult &Result, EvalInfo &Info,
4034	const Stmt S, const SwitchCase Case) {
4035	if (!Info.nextStep(S))
4036	return ESR_Failed;
4037
4038	// If we're hunting down a 'case' or 'default' label, recurse through
4039	// substatements until we hit the label.
4040	if (Case) {
4041	// FIXME: We don't start the lifetime of objects whose initialization we
4042	// jump over. However, such objects must be of class type with a trivial
4043	// default constructor that initialize all subobjects, so must be empty,
4044	// so this almost never matters.
4045	switch (S->getStmtClass()) {
4046	case Stmt::CompoundStmtClass:
4047	// FIXME: Precompute which substatement of a compound statement we
4048	// would jump to, and go straight there rather than performing a
4049	// linear scan each time.
4050	case Stmt::LabelStmtClass:
4051	case Stmt::AttributedStmtClass:
4052	case Stmt::DoStmtClass:
4053	break;
4054
4055	case Stmt::CaseStmtClass:
4056	case Stmt::DefaultStmtClass:
4057	if (Case == S)
4058	Case = nullptr;
4059	break;
4060
4061	case Stmt::IfStmtClass: {
4062	// FIXME: Precompute which side of an 'if' we would jump to, and go
4063	// straight there rather than scanning both sides.
4064	const IfStmt *IS = cast<IfStmt>(S);
4065
4066	// Wrap the evaluation in a block scope, in case it's a DeclStmt
4067	// preceded by our switch label.
4068	BlockScopeRAII Scope(Info);
4069
4070	EvalStmtResult ESR = EvaluateStmt(Result, Info, IS->getThen(), Case);
4071	if (ESR != ESR_CaseNotFound \|\| !IS->getElse())
4072	return ESR;
4073	return EvaluateStmt(Result, Info, IS->getElse(), Case);
4074	}
4075
4076	case Stmt::WhileStmtClass: {
4077	EvalStmtResult ESR =
4078	EvaluateLoopBody(Result, Info, cast<WhileStmt>(S)->getBody(), Case);
4079	if (ESR != ESR_Continue)
4080	return ESR;
4081	break;
4082	}
4083
4084	case Stmt::ForStmtClass: {
4085	const ForStmt *FS = cast<ForStmt>(S);
4086	EvalStmtResult ESR =
4087	EvaluateLoopBody(Result, Info, FS->getBody(), Case);
4088	if (ESR != ESR_Continue)
4089	return ESR;
4090	if (FS->getInc()) {
4091	FullExpressionRAII IncScope(Info);
4092	if (!EvaluateIgnoredValue(Info, FS->getInc()))
4093	return ESR_Failed;
4094	}
4095	break;
4096	}
4097
4098	case Stmt::DeclStmtClass:
4099	// FIXME: If the variable has initialization that can't be jumped over,
4100	// bail out of any immediately-surrounding compound-statement too.
4101	default:
4102	return ESR_CaseNotFound;
4103	}
4104	}
4105
4106	switch (S->getStmtClass()) {
4107	default:
4108	if (const Expr *E = dyn_cast<Expr>(S)) {
4109	// Don't bother evaluating beyond an expression-statement which couldn't
4110	// be evaluated.
4111	FullExpressionRAII Scope(Info);
4112	if (!EvaluateIgnoredValue(Info, E))
4113	return ESR_Failed;
4114	return ESR_Succeeded;
4115	}
4116
4117	Info.FFDiag(S->getBeginLoc());
4118	return ESR_Failed;
4119
4120	case Stmt::NullStmtClass:
4121	return ESR_Succeeded;
4122
4123	case Stmt::DeclStmtClass: {
4124	const DeclStmt *DS = cast<DeclStmt>(S);
4125	for (const auto *DclIt : DS->decls()) {
4126	// Each declaration initialization is its own full-expression.
4127	// FIXME: This isn't quite right; if we're performing aggregate
4128	// initialization, each braced subexpression is its own full-expression.
4129	FullExpressionRAII Scope(Info);
4130	if (!EvaluateDecl(Info, DclIt) && !Info.noteFailure())
4131	return ESR_Failed;
4132	}
4133	return ESR_Succeeded;
4134	}
4135
4136	case Stmt::ReturnStmtClass: {
4137	const Expr *RetExpr = cast<ReturnStmt>(S)->getRetValue();
4138	FullExpressionRAII Scope(Info);
4139	if (RetExpr &&
4140	!(Result.Slot
4141	? EvaluateInPlace(Result.Value, Info, *Result.Slot, RetExpr)
4142	: Evaluate(Result.Value, Info, RetExpr)))
4143	return ESR_Failed;
4144	return ESR_Returned;
4145	}
4146
4147	case Stmt::CompoundStmtClass: {
4148	BlockScopeRAII Scope(Info);
4149
4150	const CompoundStmt *CS = cast<CompoundStmt>(S);
4151	for (const auto *BI : CS->body()) {
4152	EvalStmtResult ESR = EvaluateStmt(Result, Info, BI, Case);
4153	if (ESR == ESR_Succeeded)
4154	Case = nullptr;
4155	else if (ESR != ESR_CaseNotFound)
4156	return ESR;
4157	}
4158	return Case ? ESR_CaseNotFound : ESR_Succeeded;
4159	}
4160
4161	case Stmt::IfStmtClass: {
4162	const IfStmt *IS = cast<IfStmt>(S);
4163
4164	// Evaluate the condition, as either a var decl or as an expression.
4165	BlockScopeRAII Scope(Info);
4166	if (const Stmt *Init = IS->getInit()) {
4167	EvalStmtResult ESR = EvaluateStmt(Result, Info, Init);
4168	if (ESR != ESR_Succeeded)
4169	return ESR;
4170	}
4171	bool Cond;
4172	if (!EvaluateCond(Info, IS->getConditionVariable(), IS->getCond(), Cond))
4173	return ESR_Failed;
4174
4175	if (const Stmt *SubStmt = Cond ? IS->getThen() : IS->getElse()) {
4176	EvalStmtResult ESR = EvaluateStmt(Result, Info, SubStmt);
4177	if (ESR != ESR_Succeeded)
4178	return ESR;
4179	}
4180	return ESR_Succeeded;
4181	}
4182
4183	case Stmt::WhileStmtClass: {
4184	const WhileStmt *WS = cast<WhileStmt>(S);
4185	while (true) {
4186	BlockScopeRAII Scope(Info);
4187	bool Continue;
4188	if (!EvaluateCond(Info, WS->getConditionVariable(), WS->getCond(),
4189	Continue))
4190	return ESR_Failed;
4191	if (!Continue)
4192	break;
4193
4194	EvalStmtResult ESR = EvaluateLoopBody(Result, Info, WS->getBody());
4195	if (ESR != ESR_Continue)
4196	return ESR;
4197	}
4198	return ESR_Succeeded;
4199	}
4200
4201	case Stmt::DoStmtClass: {
4202	const DoStmt *DS = cast<DoStmt>(S);
4203	bool Continue;
4204	do {
4205	EvalStmtResult ESR = EvaluateLoopBody(Result, Info, DS->getBody(), Case);
4206	if (ESR != ESR_Continue)
4207	return ESR;
4208	Case = nullptr;
4209
4210	FullExpressionRAII CondScope(Info);
4211	if (!EvaluateAsBooleanCondition(DS->getCond(), Continue, Info))
4212	return ESR_Failed;
4213	} while (Continue);
4214	return ESR_Succeeded;
4215	}
4216
4217	case Stmt::ForStmtClass: {
4218	const ForStmt *FS = cast<ForStmt>(S);
4219	BlockScopeRAII Scope(Info);
4220	if (FS->getInit()) {
4221	EvalStmtResult ESR = EvaluateStmt(Result, Info, FS->getInit());
4222	if (ESR != ESR_Succeeded)
4223	return ESR;
4224	}
4225	while (true) {
4226	BlockScopeRAII Scope(Info);
4227	bool Continue = true;
4228	if (FS->getCond() && !EvaluateCond(Info, FS->getConditionVariable(),
4229	FS->getCond(), Continue))
4230	return ESR_Failed;
4231	if (!Continue)
4232	break;
4233
4234	EvalStmtResult ESR = EvaluateLoopBody(Result, Info, FS->getBody());
4235	if (ESR != ESR_Continue)
4236	return ESR;
4237
4238	if (FS->getInc()) {
4239	FullExpressionRAII IncScope(Info);
4240	if (!EvaluateIgnoredValue(Info, FS->getInc()))
4241	return ESR_Failed;
4242	}
4243	}
4244	return ESR_Succeeded;
4245	}
4246
4247	case Stmt::CXXForRangeStmtClass: {
4248	const CXXForRangeStmt *FS = cast<CXXForRangeStmt>(S);
4249	BlockScopeRAII Scope(Info);
4250
4251	// Evaluate the init-statement if present.
4252	if (FS->getInit()) {
4253	EvalStmtResult ESR = EvaluateStmt(Result, Info, FS->getInit());
4254	if (ESR != ESR_Succeeded)
4255	return ESR;
4256	}
4257
4258	// Initialize the __range variable.
4259	EvalStmtResult ESR = EvaluateStmt(Result, Info, FS->getRangeStmt());
4260	if (ESR != ESR_Succeeded)
4261	return ESR;
4262
4263	// Create the __begin and __end iterators.
4264	ESR = EvaluateStmt(Result, Info, FS->getBeginStmt());
4265	if (ESR != ESR_Succeeded)
4266	return ESR;
4267	ESR = EvaluateStmt(Result, Info, FS->getEndStmt());
4268	if (ESR != ESR_Succeeded)
4269	return ESR;
4270
4271	while (true) {
4272	// Condition: __begin != __end.
4273	{
4274	bool Continue = true;
4275	FullExpressionRAII CondExpr(Info);
4276	if (!EvaluateAsBooleanCondition(FS->getCond(), Continue, Info))
4277	return ESR_Failed;
4278	if (!Continue)
4279	break;
4280	}
4281
4282	// User's variable declaration, initialized by *__begin.
4283	BlockScopeRAII InnerScope(Info);
4284	ESR = EvaluateStmt(Result, Info, FS->getLoopVarStmt());
4285	if (ESR != ESR_Succeeded)
4286	return ESR;
4287
4288	// Loop body.
4289	ESR = EvaluateLoopBody(Result, Info, FS->getBody());
4290	if (ESR != ESR_Continue)
4291	return ESR;
4292
4293	// Increment: ++__begin
4294	if (!EvaluateIgnoredValue(Info, FS->getInc()))
4295	return ESR_Failed;
4296	}
4297
4298	return ESR_Succeeded;
4299	}
4300
4301	case Stmt::SwitchStmtClass:
4302	return EvaluateSwitch(Result, Info, cast<SwitchStmt>(S));
4303
4304	case Stmt::ContinueStmtClass:
4305	return ESR_Continue;
4306
4307	case Stmt::BreakStmtClass:
4308	return ESR_Break;
4309
4310	case Stmt::LabelStmtClass:
4311	return EvaluateStmt(Result, Info, cast<LabelStmt>(S)->getSubStmt(), Case);
4312
4313	case Stmt::AttributedStmtClass:
4314	// As a general principle, C++11 attributes can be ignored without
4315	// any semantic impact.
4316	return EvaluateStmt(Result, Info, cast<AttributedStmt>(S)->getSubStmt(),
4317	Case);
4318
4319	case Stmt::CaseStmtClass:
4320	case Stmt::DefaultStmtClass:
4321	return EvaluateStmt(Result, Info, cast<SwitchCase>(S)->getSubStmt(), Case);
4322	case Stmt::CXXTryStmtClass:
4323	// Evaluate try blocks by evaluating all sub statements.
4324	return EvaluateStmt(Result, Info, cast<CXXTryStmt>(S)->getTryBlock(), Case);
4325	}
4326	}
4327
4328	/// CheckTrivialDefaultConstructor - Check whether a constructor is a trivial
4329	/// default constructor. If so, we'll fold it whether or not it's marked as
4330	/// constexpr. If it is marked as constexpr, we will never implicitly define it,
4331	/// so we need special handling.
4332	static bool CheckTrivialDefaultConstructor(EvalInfo &Info, SourceLocation Loc,
4333	const CXXConstructorDecl *CD,
4334	bool IsValueInitialization) {
4335	if (!CD->isTrivial() \|\| !CD->isDefaultConstructor())
4336	return false;
4337
4338	// Value-initialization does not call a trivial default constructor, so such a
4339	// call is a core constant expression whether or not the constructor is
4340	// constexpr.
4341	if (!CD->isConstexpr() && !IsValueInitialization) {
4342	if (Info.getLangOpts().CPlusPlus11) {
4343	// FIXME: If DiagDecl is an implicitly-declared special member function,
4344	// we should be much more explicit about why it's not constexpr.
4345	Info.CCEDiag(Loc, diag::note_constexpr_invalid_function, 1)
4346	<< /IsConstexpr/0 << /IsConstructor/1 << CD;
4347	Info.Note(CD->getLocation(), diag::note_declared_at);
4348	} else {
4349	Info.CCEDiag(Loc, diag::note_invalid_subexpr_in_const_expr);
4350	}
4351	}
4352	return true;
4353	}
4354
4355	/// CheckConstexprFunction - Check that a function can be called in a constant
4356	/// expression.
4357	static bool CheckConstexprFunction(EvalInfo &Info, SourceLocation CallLoc,
4358	const FunctionDecl *Declaration,
4359	const FunctionDecl *Definition,
4360	const Stmt *Body) {
4361	// Potential constant expressions can contain calls to declared, but not yet
4362	// defined, constexpr functions.
4363	if (Info.checkingPotentialConstantExpression() && !Definition &&
4364	Declaration->isConstexpr())
4365	return false;
4366
4367	// Bail out if the function declaration itself is invalid. We will
4368	// have produced a relevant diagnostic while parsing it, so just
4369	// note the problematic sub-expression.
4370	if (Declaration->isInvalidDecl()) {
4371	Info.FFDiag(CallLoc, diag::note_invalid_subexpr_in_const_expr);
4372	return false;
4373	}
4374
4375	// Can we evaluate this function call?
4376	if (Definition && Definition->isConstexpr() &&
4377	!Definition->isInvalidDecl() && Body)
4378	return true;
4379
4380	if (Info.getLangOpts().CPlusPlus11) {
4381	const FunctionDecl *DiagDecl = Definition ? Definition : Declaration;
4382
4383	// If this function is not constexpr because it is an inherited
4384	// non-constexpr constructor, diagnose that directly.
4385	auto *CD = dyn_cast<CXXConstructorDecl>(DiagDecl);
4386	if (CD && CD->isInheritingConstructor()) {
4387	auto *Inherited = CD->getInheritedConstructor().getConstructor();
4388	if (!Inherited->isConstexpr())
4389	DiagDecl = CD = Inherited;
4390	}
4391
4392	// FIXME: If DiagDecl is an implicitly-declared special member function
4393	// or an inheriting constructor, we should be much more explicit about why
4394	// it's not constexpr.
4395	if (CD && CD->isInheritingConstructor())
4396	Info.FFDiag(CallLoc, diag::note_constexpr_invalid_inhctor, 1)
4397	<< CD->getInheritedConstructor().getConstructor()->getParent();
4398	else
4399	Info.FFDiag(CallLoc, diag::note_constexpr_invalid_function, 1)
4400	<< DiagDecl->isConstexpr() << (bool)CD << DiagDecl;
4401	Info.Note(DiagDecl->getLocation(), diag::note_declared_at);
4402	} else {
4403	Info.FFDiag(CallLoc, diag::note_invalid_subexpr_in_const_expr);
4404	}
4405	return false;
4406	}
4407
4408	/// Determine if a class has any fields that might need to be copied by a
4409	/// trivial copy or move operation.
4410	static bool hasFields(const CXXRecordDecl *RD) {
4411	if (!RD \|\| RD->isEmpty())
4412	return false;
4413	for (auto *FD : RD->fields()) {
4414	if (FD->isUnnamedBitfield())
4415	continue;
4416	return true;
4417	}
4418	for (auto &Base : RD->bases())
4419	if (hasFields(Base.getType()->getAsCXXRecordDecl()))
4420	return true;
4421	return false;
4422	}
4423
4424	namespace {
4425	typedef SmallVector<APValue, 8> ArgVector;
4426	}
4427
4428	/// EvaluateArgs - Evaluate the arguments to a function call.
4429	static bool EvaluateArgs(ArrayRef<const Expr*> Args, ArgVector &ArgValues,
4430	EvalInfo &Info) {
4431	bool Success = true;
4432	for (ArrayRef<const Expr*>::iterator I = Args.begin(), E = Args.end();
4433	I != E; ++I) {
4434	if (!Evaluate(ArgValues[I - Args.begin()], Info, *I)) {
4435	// If we're checking for a potential constant expression, evaluate all
4436	// initializers even if some of them fail.
4437	if (!Info.noteFailure())
4438	return false;
4439	Success = false;
4440	}
4441	}
4442	return Success;
4443	}
4444
4445	/// Evaluate a function call.
4446	static bool HandleFunctionCall(SourceLocation CallLoc,
4447	const FunctionDecl Callee, const LValue This,
4448	ArrayRef<const Expr> Args, const Stmt Body,
4449	EvalInfo &Info, APValue &Result,
4450	const LValue *ResultSlot) {
4451	ArgVector ArgValues(Args.size());
4452	if (!EvaluateArgs(Args, ArgValues, Info))
4453	return false;
4454
4455	if (!Info.CheckCallLimit(CallLoc))
4456	return false;
4457
4458	CallStackFrame Frame(Info, CallLoc, Callee, This, ArgValues.data());
4459
4460	// For a trivial copy or move assignment, perform an APValue copy. This is
4461	// essential for unions, where the operations performed by the assignment
4462	// operator cannot be represented as statements.
4463	//
4464	// Skip this for non-union classes with no fields; in that case, the defaulted
4465	// copy/move does not actually read the object.
4466	const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(Callee);
4467	if (MD && MD->isDefaulted() &&
4468	(MD->getParent()->isUnion() \|\|
4469	(MD->isTrivial() && hasFields(MD->getParent())))) {
4470	isCopyAssignmentOperator() \|\| MD->isMoveAssignmentOperator())", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 4471, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(This &&
4471	isCopyAssignmentOperator() \|\| MD->isMoveAssignmentOperator())", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 4471, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true"> (MD->isCopyAssignmentOperator() \|\| MD->isMoveAssignmentOperator()));
4472	LValue RHS;
4473	RHS.setFrom(Info.Ctx, ArgValues[0]);
4474	APValue RHSValue;
4475	if (!handleLValueToRValueConversion(Info, Args[0], Args[0]->getType(),
4476	RHS, RHSValue))
4477	return false;
4478	if (!handleAssignment(Info, Args[0], *This, MD->getThisType(),
4479	RHSValue))
4480	return false;
4481	This->moveInto(Result);
4482	return true;
4483	} else if (MD && isLambdaCallOperator(MD)) {
4484	// We're in a lambda; determine the lambda capture field maps unless we're
4485	// just constexpr checking a lambda's call operator. constexpr checking is
4486	// done before the captures have been added to the closure object (unless
4487	// we're inferring constexpr-ness), so we don't have access to them in this
4488	// case. But since we don't need the captures to constexpr check, we can
4489	// just ignore them.
4490	if (!Info.checkingPotentialConstantExpression())
4491	MD->getParent()->getCaptureFields(Frame.LambdaCaptureFields,
4492	Frame.LambdaThisCaptureField);
4493	}
4494
4495	StmtResult Ret = {Result, ResultSlot};
4496	EvalStmtResult ESR = EvaluateStmt(Ret, Info, Body);
4497	if (ESR == ESR_Succeeded) {
4498	if (Callee->getReturnType()->isVoidType())
4499	return true;
4500	Info.FFDiag(Callee->getEndLoc(), diag::note_constexpr_no_return);
4501	}
4502	return ESR == ESR_Returned;
4503	}
4504
4505	/// Evaluate a constructor call.
4506	static bool HandleConstructorCall(const Expr *E, const LValue &This,
4507	APValue *ArgValues,
4508	const CXXConstructorDecl *Definition,
4509	EvalInfo &Info, APValue &Result) {
4510	SourceLocation CallLoc = E->getExprLoc();
4511	if (!Info.CheckCallLimit(CallLoc))
4512	return false;
4513
4514	const CXXRecordDecl *RD = Definition->getParent();
4515	if (RD->getNumVBases()) {
4516	Info.FFDiag(CallLoc, diag::note_constexpr_virtual_base) << RD;
4517	return false;
4518	}
4519
4520	EvalInfo::EvaluatingConstructorRAII EvalObj(
4521	Info, {This.getLValueBase(),
4522	{This.getLValueCallIndex(), This.getLValueVersion()}});
4523	CallStackFrame Frame(Info, CallLoc, Definition, &This, ArgValues);
4524
4525	// FIXME: Creating an APValue just to hold a nonexistent return value is
4526	// wasteful.
4527	APValue RetVal;
4528	StmtResult Ret = {RetVal, nullptr};
4529
4530	// If it's a delegating constructor, delegate.
4531	if (Definition->isDelegatingConstructor()) {
4532	CXXConstructorDecl::init_const_iterator I = Definition->init_begin();
4533	{
4534	FullExpressionRAII InitScope(Info);
4535	if (!EvaluateInPlace(Result, Info, This, (*I)->getInit()))
4536	return false;
4537	}
4538	return EvaluateStmt(Ret, Info, Definition->getBody()) != ESR_Failed;
4539	}
4540
4541	// For a trivial copy or move constructor, perform an APValue copy. This is
4542	// essential for unions (or classes with anonymous union members), where the
4543	// operations performed by the constructor cannot be represented by
4544	// ctor-initializers.
4545	//
4546	// Skip this for empty non-union classes; we should not perform an
4547	// lvalue-to-rvalue conversion on them because their copy constructor does not
4548	// actually read them.
4549	if (Definition->isDefaulted() && Definition->isCopyOrMoveConstructor() &&
4550	(Definition->getParent()->isUnion() \|\|
4551	(Definition->isTrivial() && hasFields(Definition->getParent())))) {
4552	LValue RHS;
4553	RHS.setFrom(Info.Ctx, ArgValues[0]);
4554	return handleLValueToRValueConversion(
4555	Info, E, Definition->getParamDecl(0)->getType().getNonReferenceType(),
4556	RHS, Result);
4557	}
4558
4559	// Reserve space for the struct members.
4560	if (!RD->isUnion() && Result.isUninit())
4561	Result = APValue(APValue::UninitStruct(), RD->getNumBases(),
4562	std::distance(RD->field_begin(), RD->field_end()));
4563
4564	if (RD->isInvalidDecl()) return false;
4565	const ASTRecordLayout &Layout = Info.Ctx.getASTRecordLayout(RD);
4566
4567	// A scope for temporaries lifetime-extended by reference members.
4568	BlockScopeRAII LifetimeExtendedScope(Info);
4569
4570	bool Success = true;
4571	unsigned BasesSeen = 0;
4572	#ifndef NDEBUG
4573	CXXRecordDecl::base_class_const_iterator BaseIt = RD->bases_begin();
4574	#endif
4575	for (const auto *I : Definition->inits()) {
4576	LValue Subobject = This;
4577	LValue SubobjectParent = This;
4578	APValue *Value = &Result;
4579
4580	// Determine the subobject to initialize.
4581	FieldDecl *FD = nullptr;
4582	if (I->isBaseInitializer()) {
4583	QualType BaseType(I->getBaseClass(), 0);
4584	#ifndef NDEBUG
4585	// Non-virtual base classes are initialized in the order in the class
4586	// definition. We have already checked for virtual base classes.
4587	(0) . __assert_fail ("!BaseIt->isVirtual() && \"virtual base for literal type\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 4587, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(!BaseIt->isVirtual() && "virtual base for literal type");
4588	(0) . __assert_fail ("Info.Ctx.hasSameType(BaseIt->getType(), BaseType) && \"base class initializers not in expected order\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 4589, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(Info.Ctx.hasSameType(BaseIt->getType(), BaseType) &&
4589	(0) . __assert_fail ("Info.Ctx.hasSameType(BaseIt->getType(), BaseType) && \"base class initializers not in expected order\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 4589, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true"> "base class initializers not in expected order");
4590	++BaseIt;
4591	#endif
4592	if (!HandleLValueDirectBase(Info, I->getInit(), Subobject, RD,
4593	BaseType->getAsCXXRecordDecl(), &Layout))
4594	return false;
4595	Value = &Result.getStructBase(BasesSeen++);
4596	} else if ((FD = I->getMember())) {
4597	if (!HandleLValueMember(Info, I->getInit(), Subobject, FD, &Layout))
4598	return false;
4599	if (RD->isUnion()) {
4600	Result = APValue(FD);
4601	Value = &Result.getUnionValue();
4602	} else {
4603	Value = &Result.getStructField(FD->getFieldIndex());
4604	}
4605	} else if (IndirectFieldDecl *IFD = I->getIndirectMember()) {
4606	// Walk the indirect field decl's chain to find the object to initialize,
4607	// and make sure we've initialized every step along it.
4608	auto IndirectFieldChain = IFD->chain();
4609	for (auto *C : IndirectFieldChain) {
4610	FD = cast<FieldDecl>(C);
4611	CXXRecordDecl *CD = cast<CXXRecordDecl>(FD->getParent());
4612	// Switch the union field if it differs. This happens if we had
4613	// preceding zero-initialization, and we're now initializing a union
4614	// subobject other than the first.
4615	// FIXME: In this case, the values of the other subobjects are
4616	// specified, since zero-initialization sets all padding bits to zero.
4617	if (Value->isUninit() \|\|
4618	(Value->isUnion() && Value->getUnionField() != FD)) {
4619	if (CD->isUnion())
4620	*Value = APValue(FD);
4621	else
4622	*Value = APValue(APValue::UninitStruct(), CD->getNumBases(),
4623	std::distance(CD->field_begin(), CD->field_end()));
4624	}
4625	// Store Subobject as its parent before updating it for the last element
4626	// in the chain.
4627	if (C == IndirectFieldChain.back())
4628	SubobjectParent = Subobject;
4629	if (!HandleLValueMember(Info, I->getInit(), Subobject, FD))
4630	return false;
4631	if (CD->isUnion())
4632	Value = &Value->getUnionValue();
4633	else
4634	Value = &Value->getStructField(FD->getFieldIndex());
4635	}
4636	} else {
4637	llvm_unreachable("unknown base initializer kind");
4638	}
4639
4640	// Need to override This for implicit field initializers as in this case
4641	// This refers to innermost anonymous struct/union containing initializer,
4642	// not to currently constructed class.
4643	const Expr *Init = I->getInit();
4644	ThisOverrideRAII ThisOverride(*Info.CurrentCall, &SubobjectParent,
4645	isa<CXXDefaultInitExpr>(Init));
4646	FullExpressionRAII InitScope(Info);
4647	if (!EvaluateInPlace(*Value, Info, Subobject, Init) \|\|
4648	(FD && FD->isBitField() &&
4649	!truncateBitfieldValue(Info, Init, *Value, FD))) {
4650	// If we're checking for a potential constant expression, evaluate all
4651	// initializers even if some of them fail.
4652	if (!Info.noteFailure())
4653	return false;
4654	Success = false;
4655	}
4656	}
4657
4658	return Success &&
4659	EvaluateStmt(Ret, Info, Definition->getBody()) != ESR_Failed;
4660	}
4661
4662	static bool HandleConstructorCall(const Expr *E, const LValue &This,
4663	ArrayRef<const Expr*> Args,
4664	const CXXConstructorDecl *Definition,
4665	EvalInfo &Info, APValue &Result) {
4666	ArgVector ArgValues(Args.size());
4667	if (!EvaluateArgs(Args, ArgValues, Info))
4668	return false;
4669
4670	return HandleConstructorCall(E, This, ArgValues.data(), Definition,
4671	Info, Result);
4672	}
4673
4674	//===----------------------------------------------------------------------===//
4675	// Generic Evaluation
4676	//===----------------------------------------------------------------------===//
4677	namespace {
4678
4679	template <class Derived>
4680	class ExprEvaluatorBase
4681	: public ConstStmtVisitor<Derived, bool> {
4682	private:
4683	Derived &getDerived() { return static_cast<Derived&>(*this); }
4684	bool DerivedSuccess(const APValue &V, const Expr *E) {
4685	return getDerived().Success(V, E);
4686	}
4687	bool DerivedZeroInitialization(const Expr *E) {
4688	return getDerived().ZeroInitialization(E);
4689	}
4690
4691	// Check whether a conditional operator with a non-constant condition is a
4692	// potential constant expression. If neither arm is a potential constant
4693	// expression, then the conditional operator is not either.
4694	template<typename ConditionalOperator>
4695	void CheckPotentialConstantConditional(const ConditionalOperator *E) {
4696	assert(Info.checkingPotentialConstantExpression());
4697
4698	// Speculatively evaluate both arms.
4699	SmallVector<PartialDiagnosticAt, 8> Diag;
4700	{
4701	SpeculativeEvaluationRAII Speculate(Info, &Diag);
4702	StmtVisitorTy::Visit(E->getFalseExpr());
4703	if (Diag.empty())
4704	return;
4705	}
4706
4707	{
4708	SpeculativeEvaluationRAII Speculate(Info, &Diag);
4709	Diag.clear();
4710	StmtVisitorTy::Visit(E->getTrueExpr());
4711	if (Diag.empty())
4712	return;
4713	}
4714
4715	Error(E, diag::note_constexpr_conditional_never_const);
4716	}
4717
4718
4719	template<typename ConditionalOperator>
4720	bool HandleConditionalOperator(const ConditionalOperator *E) {
4721	bool BoolResult;
4722	if (!EvaluateAsBooleanCondition(E->getCond(), BoolResult, Info)) {
4723	if (Info.checkingPotentialConstantExpression() && Info.noteFailure()) {
4724	CheckPotentialConstantConditional(E);
4725	return false;
4726	}
4727	if (Info.noteFailure()) {
4728	StmtVisitorTy::Visit(E->getTrueExpr());
4729	StmtVisitorTy::Visit(E->getFalseExpr());
4730	}
4731	return false;
4732	}
4733
4734	Expr *EvalExpr = BoolResult ? E->getTrueExpr() : E->getFalseExpr();
4735	return StmtVisitorTy::Visit(EvalExpr);
4736	}
4737
4738	protected:
4739	EvalInfo &Info;
4740	typedef ConstStmtVisitor<Derived, bool> StmtVisitorTy;
4741	typedef ExprEvaluatorBase ExprEvaluatorBaseTy;
4742
4743	OptionalDiagnostic CCEDiag(const Expr *E, diag::kind D) {
4744	return Info.CCEDiag(E, D);
4745	}
4746
4747	bool ZeroInitialization(const Expr *E) { return Error(E); }
4748
4749	public:
4750	ExprEvaluatorBase(EvalInfo &Info) : Info(Info) {}
4751
4752	EvalInfo &getEvalInfo() { return Info; }
4753
4754	/// Report an evaluation error. This should only be called when an error is
4755	/// first discovered. When propagating an error, just return false.
4756	bool Error(const Expr *E, diag::kind D) {
4757	Info.FFDiag(E, D);
4758	return false;
4759	}
4760	bool Error(const Expr *E) {
4761	return Error(E, diag::note_invalid_subexpr_in_const_expr);
4762	}
4763
4764	bool VisitStmt(const Stmt *) {
4765	llvm_unreachable("Expression evaluator should not be called on stmts");
4766	}
4767	bool VisitExpr(const Expr *E) {
4768	return Error(E);
4769	}
4770
4771	bool VisitConstantExpr(const ConstantExpr *E)
4772	{ return StmtVisitorTy::Visit(E->getSubExpr()); }
4773	bool VisitParenExpr(const ParenExpr *E)
4774	{ return StmtVisitorTy::Visit(E->getSubExpr()); }
4775	bool VisitUnaryExtension(const UnaryOperator *E)
4776	{ return StmtVisitorTy::Visit(E->getSubExpr()); }
4777	bool VisitUnaryPlus(const UnaryOperator *E)
4778	{ return StmtVisitorTy::Visit(E->getSubExpr()); }
4779	bool VisitChooseExpr(const ChooseExpr *E)
4780	{ return StmtVisitorTy::Visit(E->getChosenSubExpr()); }
4781	bool VisitGenericSelectionExpr(const GenericSelectionExpr *E)
4782	{ return StmtVisitorTy::Visit(E->getResultExpr()); }
4783	bool VisitSubstNonTypeTemplateParmExpr(const SubstNonTypeTemplateParmExpr *E)
4784	{ return StmtVisitorTy::Visit(E->getReplacement()); }
4785	bool VisitCXXDefaultArgExpr(const CXXDefaultArgExpr *E) {
4786	TempVersionRAII RAII(*Info.CurrentCall);
4787	return StmtVisitorTy::Visit(E->getExpr());
4788	}
4789	bool VisitCXXDefaultInitExpr(const CXXDefaultInitExpr *E) {
4790	TempVersionRAII RAII(*Info.CurrentCall);
4791	// The initializer may not have been parsed yet, or might be erroneous.
4792	if (!E->getExpr())
4793	return Error(E);
4794	return StmtVisitorTy::Visit(E->getExpr());
4795	}
4796	// We cannot create any objects for which cleanups are required, so there is
4797	// nothing to do here; all cleanups must come from unevaluated subexpressions.
4798	bool VisitExprWithCleanups(const ExprWithCleanups *E)
4799	{ return StmtVisitorTy::Visit(E->getSubExpr()); }
4800
4801	bool VisitCXXReinterpretCastExpr(const CXXReinterpretCastExpr *E) {
4802	CCEDiag(E, diag::note_constexpr_invalid_cast) << 0;
4803	return static_cast<Derived*>(this)->VisitCastExpr(E);
4804	}
4805	bool VisitCXXDynamicCastExpr(const CXXDynamicCastExpr *E) {
4806	CCEDiag(E, diag::note_constexpr_invalid_cast) << 1;
4807	return static_cast<Derived*>(this)->VisitCastExpr(E);
4808	}
4809
4810	bool VisitBinaryOperator(const BinaryOperator *E) {
4811	switch (E->getOpcode()) {
4812	default:
4813	return Error(E);
4814
4815	case BO_Comma:
4816	VisitIgnoredValue(E->getLHS());
4817	return StmtVisitorTy::Visit(E->getRHS());
4818
4819	case BO_PtrMemD:
4820	case BO_PtrMemI: {
4821	LValue Obj;
4822	if (!HandleMemberPointerAccess(Info, E, Obj))
4823	return false;
4824	APValue Result;
4825	if (!handleLValueToRValueConversion(Info, E, E->getType(), Obj, Result))
4826	return false;
4827	return DerivedSuccess(Result, E);
4828	}
4829	}
4830	}
4831
4832	bool VisitBinaryConditionalOperator(const BinaryConditionalOperator *E) {
4833	// Evaluate and cache the common expression. We treat it as a temporary,
4834	// even though it's not quite the same thing.
4835	if (!Evaluate(Info.CurrentCall->createTemporary(E->getOpaqueValue(), false),
4836	Info, E->getCommon()))
4837	return false;
4838
4839	return HandleConditionalOperator(E);
4840	}
4841
4842	bool VisitConditionalOperator(const ConditionalOperator *E) {
4843	bool IsBcpCall = false;
4844	// If the condition (ignoring parens) is a __builtin_constant_p call,
4845	// the result is a constant expression if it can be folded without
4846	// side-effects. This is an important GNU extension. See GCC PR38377
4847	// for discussion.
4848	if (const CallExpr *CallCE =
4849	dyn_cast<CallExpr>(E->getCond()->IgnoreParenCasts()))
4850	if (CallCE->getBuiltinCallee() == Builtin::BI__builtin_constant_p)
4851	IsBcpCall = true;
4852
4853	// Always assume __builtin_constant_p(...) ? ... : ... is a potential
4854	// constant expression; we can't check whether it's potentially foldable.
4855	if (Info.checkingPotentialConstantExpression() && IsBcpCall)
4856	return false;
4857
4858	FoldConstant Fold(Info, IsBcpCall);
4859	if (!HandleConditionalOperator(E)) {
4860	Fold.keepDiagnostics();
4861	return false;
4862	}
4863
4864	return true;
4865	}
4866
4867	bool VisitOpaqueValueExpr(const OpaqueValueExpr *E) {
4868	if (APValue *Value = Info.CurrentCall->getCurrentTemporary(E))
4869	return DerivedSuccess(*Value, E);
4870
4871	const Expr *Source = E->getSourceExpr();
4872	if (!Source)
4873	return Error(E);
4874	if (Source == E) { // sanity checking.
4875	(0) . __assert_fail ("0 && \"OpaqueValueExpr recursively refers to itself\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 4875, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(0 && "OpaqueValueExpr recursively refers to itself");
4876	return Error(E);
4877	}
4878	return StmtVisitorTy::Visit(Source);
4879	}
4880
4881	bool VisitCallExpr(const CallExpr *E) {
4882	APValue Result;
4883	if (!handleCallExpr(E, Result, nullptr))
4884	return false;
4885	return DerivedSuccess(Result, E);
4886	}
4887
4888	bool handleCallExpr(const CallExpr *E, APValue &Result,
4889	const LValue *ResultSlot) {
4890	const Expr *Callee = E->getCallee()->IgnoreParens();
4891	QualType CalleeType = Callee->getType();
4892
4893	const FunctionDecl *FD = nullptr;
4894	LValue *This = nullptr, ThisVal;
4895	auto Args = llvm::makeArrayRef(E->getArgs(), E->getNumArgs());
4896	bool HasQualifier = false;
4897
4898	// Extract function decl and 'this' pointer from the callee.
4899	if (CalleeType->isSpecificBuiltinType(BuiltinType::BoundMember)) {
4900	const ValueDecl *Member = nullptr;
4901	if (const MemberExpr *ME = dyn_cast<MemberExpr>(Callee)) {
4902	// Explicit bound member calls, such as x.f() or p->g();
4903	if (!EvaluateObjectArgument(Info, ME->getBase(), ThisVal))
4904	return false;
4905	Member = ME->getMemberDecl();
4906	This = &ThisVal;
4907	HasQualifier = ME->hasQualifier();
4908	} else if (const BinaryOperator *BE = dyn_cast<BinaryOperator>(Callee)) {
4909	// Indirect bound member calls ('.' or '->').
4910	Member = HandleMemberPointerAccess(Info, BE, ThisVal, false);
4911	if (!Member) return false;
4912	This = &ThisVal;
4913	} else
4914	return Error(Callee);
4915
4916	FD = dyn_cast<FunctionDecl>(Member);
4917	if (!FD)
4918	return Error(Callee);
4919	} else if (CalleeType->isFunctionPointerType()) {
4920	LValue Call;
4921	if (!EvaluatePointer(Callee, Call, Info))
4922	return false;
4923
4924	if (!Call.getLValueOffset().isZero())
4925	return Error(Callee);
4926	FD = dyn_cast_or_null<FunctionDecl>(
4927	Call.getLValueBase().dyn_cast<const ValueDecl*>());
4928	if (!FD)
4929	return Error(Callee);
4930	// Don't call function pointers which have been cast to some other type.
4931	// Per DR (no number yet), the caller and callee can differ in noexcept.
4932	if (!Info.Ctx.hasSameFunctionTypeIgnoringExceptionSpec(
4933	CalleeType->getPointeeType(), FD->getType())) {
4934	return Error(E);
4935	}
4936
4937	// Overloaded operator calls to member functions are represented as normal
4938	// calls with '*this' as the first argument.
4939	const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD);
4940	if (MD && !MD->isStatic()) {
4941	// FIXME: When selecting an implicit conversion for an overloaded
4942	// operator delete, we sometimes try to evaluate calls to conversion
4943	// operators without a 'this' parameter!
4944	if (Args.empty())
4945	return Error(E);
4946
4947	if (!EvaluateObjectArgument(Info, Args[0], ThisVal))
4948	return false;
4949	This = &ThisVal;
4950	Args = Args.slice(1);
4951	} else if (MD && MD->isLambdaStaticInvoker()) {
4952	// Map the static invoker for the lambda back to the call operator.
4953	// Conveniently, we don't have to slice out the 'this' argument (as is
4954	// being done for the non-static case), since a static member function
4955	// doesn't have an implicit argument passed in.
4956	const CXXRecordDecl *ClosureClass = MD->getParent();
4957	(0) . __assert_fail ("ClosureClass->captures_begin() == ClosureClass->captures_end() && \"Number of captures must be zero for conversion to function-ptr\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 4959, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(
4958	(0) . __assert_fail ("ClosureClass->captures_begin() == ClosureClass->captures_end() && \"Number of captures must be zero for conversion to function-ptr\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 4959, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true"> ClosureClass->captures_begin() == ClosureClass->captures_end() &&
4959	(0) . __assert_fail ("ClosureClass->captures_begin() == ClosureClass->captures_end() && \"Number of captures must be zero for conversion to function-ptr\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 4959, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true"> "Number of captures must be zero for conversion to function-ptr");
4960
4961	const CXXMethodDecl *LambdaCallOp =
4962	ClosureClass->getLambdaCallOperator();
4963
4964	// Set 'FD', the function that will be called below, to the call
4965	// operator. If the closure object represents a generic lambda, find
4966	// the corresponding specialization of the call operator.
4967
4968	if (ClosureClass->isGenericLambda()) {
4969	(0) . __assert_fail ("MD->isFunctionTemplateSpecialization() && \"A generic lambda's static-invoker function must be a \" \"template specialization\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 4971, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(MD->isFunctionTemplateSpecialization() &&
4970	(0) . __assert_fail ("MD->isFunctionTemplateSpecialization() && \"A generic lambda's static-invoker function must be a \" \"template specialization\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 4971, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true"> "A generic lambda's static-invoker function must be a "
4971	(0) . __assert_fail ("MD->isFunctionTemplateSpecialization() && \"A generic lambda's static-invoker function must be a \" \"template specialization\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 4971, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true"> "template specialization");
4972	const TemplateArgumentList *TAL = MD->getTemplateSpecializationArgs();
4973	FunctionTemplateDecl *CallOpTemplate =
4974	LambdaCallOp->getDescribedFunctionTemplate();
4975	void *InsertPos = nullptr;
4976	FunctionDecl *CorrespondingCallOpSpecialization =
4977	CallOpTemplate->findSpecialization(TAL->asArray(), InsertPos);
4978	(0) . __assert_fail ("CorrespondingCallOpSpecialization && \"We must always have a function call operator specialization \" \"that corresponds to our static invoker specialization\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 4980, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(CorrespondingCallOpSpecialization &&
4979	(0) . __assert_fail ("CorrespondingCallOpSpecialization && \"We must always have a function call operator specialization \" \"that corresponds to our static invoker specialization\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 4980, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true"> "We must always have a function call operator specialization "
4980	(0) . __assert_fail ("CorrespondingCallOpSpecialization && \"We must always have a function call operator specialization \" \"that corresponds to our static invoker specialization\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 4980, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true"> "that corresponds to our static invoker specialization");
4981	FD = cast<CXXMethodDecl>(CorrespondingCallOpSpecialization);
4982	} else
4983	FD = LambdaCallOp;
4984	}
4985
4986
4987	} else
4988	return Error(E);
4989
4990	if (This && !This->checkSubobject(Info, E, CSK_This))
4991	return false;
4992
4993	// DR1358 allows virtual constexpr functions in some cases. Don't allow
4994	// calls to such functions in constant expressions.
4995	if (This && !HasQualifier &&
4996	isa<CXXMethodDecl>(FD) && cast<CXXMethodDecl>(FD)->isVirtual())
4997	return Error(E, diag::note_constexpr_virtual_call);
4998
4999	const FunctionDecl *Definition = nullptr;
5000	Stmt *Body = FD->getBody(Definition);
5001
5002	if (!CheckConstexprFunction(Info, E->getExprLoc(), FD, Definition, Body) \|\|
5003	!HandleFunctionCall(E->getExprLoc(), Definition, This, Args, Body, Info,
5004	Result, ResultSlot))
5005	return false;
5006
5007	return true;
5008	}
5009
5010	bool VisitCompoundLiteralExpr(const CompoundLiteralExpr *E) {
5011	return StmtVisitorTy::Visit(E->getInitializer());
5012	}
5013	bool VisitInitListExpr(const InitListExpr *E) {
5014	if (E->getNumInits() == 0)
5015	return DerivedZeroInitialization(E);
5016	if (E->getNumInits() == 1)
5017	return StmtVisitorTy::Visit(E->getInit(0));
5018	return Error(E);
5019	}
5020	bool VisitImplicitValueInitExpr(const ImplicitValueInitExpr *E) {
5021	return DerivedZeroInitialization(E);
5022	}
5023	bool VisitCXXScalarValueInitExpr(const CXXScalarValueInitExpr *E) {
5024	return DerivedZeroInitialization(E);
5025	}
5026	bool VisitCXXNullPtrLiteralExpr(const CXXNullPtrLiteralExpr *E) {
5027	return DerivedZeroInitialization(E);
5028	}
5029
5030	/// A member expression where the object is a prvalue is itself a prvalue.
5031	bool VisitMemberExpr(const MemberExpr *E) {
5032	(0) . __assert_fail ("!E->isArrow() && \"missing call to bound member function?\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 5032, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(!E->isArrow() && "missing call to bound member function?");
5033
5034	APValue Val;
5035	if (!Evaluate(Val, Info, E->getBase()))
5036	return false;
5037
5038	QualType BaseTy = E->getBase()->getType();
5039
5040	const FieldDecl *FD = dyn_cast<FieldDecl>(E->getMemberDecl());
5041	if (!FD) return Error(E);
5042	(0) . __assert_fail ("!FD->getType()->isReferenceType() && \"prvalue reference?\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 5042, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(!FD->getType()->isReferenceType() && "prvalue reference?");
5043	(0) . __assert_fail ("BaseTy->castAs()->getDecl()->getCanonicalDecl() == FD->getParent()->getCanonicalDecl() && \"record / field mismatch\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 5044, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(BaseTy->castAs<RecordType>()->getDecl()->getCanonicalDecl() ==
5044	(0) . __assert_fail ("BaseTy->castAs()->getDecl()->getCanonicalDecl() == FD->getParent()->getCanonicalDecl() && \"record / field mismatch\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 5044, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true"> FD->getParent()->getCanonicalDecl() && "record / field mismatch");
5045
5046	CompleteObject Obj(&Val, BaseTy, true);
5047	SubobjectDesignator Designator(BaseTy);
5048	Designator.addDeclUnchecked(FD);
5049
5050	APValue Result;
5051	return extractSubobject(Info, E, Obj, Designator, Result) &&
5052	DerivedSuccess(Result, E);
5053	}
5054
5055	bool VisitCastExpr(const CastExpr *E) {
5056	switch (E->getCastKind()) {
5057	default:
5058	break;
5059
5060	case CK_AtomicToNonAtomic: {
5061	APValue AtomicVal;
5062	// This does not need to be done in place even for class/array types:
5063	// atomic-to-non-atomic conversion implies copying the object
5064	// representation.
5065	if (!Evaluate(AtomicVal, Info, E->getSubExpr()))
5066	return false;
5067	return DerivedSuccess(AtomicVal, E);
5068	}
5069
5070	case CK_NoOp:
5071	case CK_UserDefinedConversion:
5072	return StmtVisitorTy::Visit(E->getSubExpr());
5073
5074	case CK_LValueToRValue: {
5075	LValue LVal;
5076	if (!EvaluateLValue(E->getSubExpr(), LVal, Info))
5077	return false;
5078	APValue RVal;
5079	// Note, we use the subexpression's type in order to retain cv-qualifiers.
5080	if (!handleLValueToRValueConversion(Info, E, E->getSubExpr()->getType(),
5081	LVal, RVal))
5082	return false;
5083	return DerivedSuccess(RVal, E);
5084	}
5085	}
5086
5087	return Error(E);
5088	}
5089
5090	bool VisitUnaryPostInc(const UnaryOperator *UO) {
5091	return VisitUnaryPostIncDec(UO);
5092	}
5093	bool VisitUnaryPostDec(const UnaryOperator *UO) {
5094	return VisitUnaryPostIncDec(UO);
5095	}
5096	bool VisitUnaryPostIncDec(const UnaryOperator *UO) {
5097	if (!Info.getLangOpts().CPlusPlus14 && !Info.keepEvaluatingAfterFailure())
5098	return Error(UO);
5099
5100	LValue LVal;
5101	if (!EvaluateLValue(UO->getSubExpr(), LVal, Info))
5102	return false;
5103	APValue RVal;
5104	if (!handleIncDec(this->Info, UO, LVal, UO->getSubExpr()->getType(),
5105	UO->isIncrementOp(), &RVal))
5106	return false;
5107	return DerivedSuccess(RVal, UO);
5108	}
5109
5110	bool VisitStmtExpr(const StmtExpr *E) {
5111	// We will have checked the full-expressions inside the statement expression
5112	// when they were completed, and don't need to check them again now.
5113	if (Info.checkingForOverflow())
5114	return Error(E);
5115
5116	BlockScopeRAII Scope(Info);
5117	const CompoundStmt *CS = E->getSubStmt();
5118	if (CS->body_empty())
5119	return true;
5120
5121	for (CompoundStmt::const_body_iterator BI = CS->body_begin(),
5122	BE = CS->body_end();
5123	/**/; ++BI) {
5124	if (BI + 1 == BE) {
5125	const Expr FinalExpr = dyn_cast<Expr>(BI);
5126	if (!FinalExpr) {
5127	Info.FFDiag((*BI)->getBeginLoc(),
5128	diag::note_constexpr_stmt_expr_unsupported);
5129	return false;
5130	}
5131	return this->Visit(FinalExpr);
5132	}
5133
5134	APValue ReturnValue;
5135	StmtResult Result = { ReturnValue, nullptr };
5136	EvalStmtResult ESR = EvaluateStmt(Result, Info, *BI);
5137	if (ESR != ESR_Succeeded) {
5138	// FIXME: If the statement-expression terminated due to 'return',
5139	// 'break', or 'continue', it would be nice to propagate that to
5140	// the outer statement evaluation rather than bailing out.
5141	if (ESR != ESR_Failed)
5142	Info.FFDiag((*BI)->getBeginLoc(),
5143	diag::note_constexpr_stmt_expr_unsupported);
5144	return false;
5145	}
5146	}
5147
5148	llvm_unreachable("Return from function from the loop above.");
5149	}
5150
5151	/// Visit a value which is evaluated, but whose value is ignored.
5152	void VisitIgnoredValue(const Expr *E) {
5153	EvaluateIgnoredValue(Info, E);
5154	}
5155
5156	/// Potentially visit a MemberExpr's base expression.
5157	void VisitIgnoredBaseExpression(const Expr *E) {
5158	// While MSVC doesn't evaluate the base expression, it does diagnose the
5159	// presence of side-effecting behavior.
5160	if (Info.getLangOpts().MSVCCompat && !E->HasSideEffects(Info.Ctx))
5161	return;
5162	VisitIgnoredValue(E);
5163	}
5164	};
5165
5166	} // namespace
5167
5168	//===----------------------------------------------------------------------===//
5169	// Common base class for lvalue and temporary evaluation.
5170	//===----------------------------------------------------------------------===//
5171	namespace {
5172	template<class Derived>
5173	class LValueExprEvaluatorBase
5174	: public ExprEvaluatorBase<Derived> {
5175	protected:
5176	LValue &Result;
5177	bool InvalidBaseOK;
5178	typedef LValueExprEvaluatorBase LValueExprEvaluatorBaseTy;
5179	typedef ExprEvaluatorBase<Derived> ExprEvaluatorBaseTy;
5180
5181	bool Success(APValue::LValueBase B) {
5182	Result.set(B);
5183	return true;
5184	}
5185
5186	bool evaluatePointer(const Expr *E, LValue &Result) {
5187	return EvaluatePointer(E, Result, this->Info, InvalidBaseOK);
5188	}
5189
5190	public:
5191	LValueExprEvaluatorBase(EvalInfo &Info, LValue &Result, bool InvalidBaseOK)
5192	: ExprEvaluatorBaseTy(Info), Result(Result),
5193	InvalidBaseOK(InvalidBaseOK) {}
5194
5195	bool Success(const APValue &V, const Expr *E) {
5196	Result.setFrom(this->Info.Ctx, V);
5197	return true;
5198	}
5199
5200	bool VisitMemberExpr(const MemberExpr *E) {
5201	// Handle non-static data members.
5202	QualType BaseTy;
5203	bool EvalOK;
5204	if (E->isArrow()) {
5205	EvalOK = evaluatePointer(E->getBase(), Result);
5206	BaseTy = E->getBase()->getType()->castAs<PointerType>()->getPointeeType();
5207	} else if (E->getBase()->isRValue()) {
5208	getBase()->getType()->isRecordType()", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 5208, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(E->getBase()->getType()->isRecordType());
5209	EvalOK = EvaluateTemporary(E->getBase(), Result, this->Info);
5210	BaseTy = E->getBase()->getType();
5211	} else {
5212	EvalOK = this->Visit(E->getBase());
5213	BaseTy = E->getBase()->getType();
5214	}
5215	if (!EvalOK) {
5216	if (!InvalidBaseOK)
5217	return false;
5218	Result.setInvalid(E);
5219	return true;
5220	}
5221
5222	const ValueDecl *MD = E->getMemberDecl();
5223	if (const FieldDecl *FD = dyn_cast<FieldDecl>(E->getMemberDecl())) {
5224	(0) . __assert_fail ("BaseTy->getAs()->getDecl()->getCanonicalDecl() == FD->getParent()->getCanonicalDecl() && \"record / field mismatch\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 5225, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(BaseTy->getAs<RecordType>()->getDecl()->getCanonicalDecl() ==
5225	(0) . __assert_fail ("BaseTy->getAs()->getDecl()->getCanonicalDecl() == FD->getParent()->getCanonicalDecl() && \"record / field mismatch\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 5225, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true"> FD->getParent()->getCanonicalDecl() && "record / field mismatch");
5226	(void)BaseTy;
5227	if (!HandleLValueMember(this->Info, E, Result, FD))
5228	return false;
5229	} else if (const IndirectFieldDecl *IFD = dyn_cast<IndirectFieldDecl>(MD)) {
5230	if (!HandleLValueIndirectMember(this->Info, E, Result, IFD))
5231	return false;
5232	} else
5233	return this->Error(E);
5234
5235	if (MD->getType()->isReferenceType()) {
5236	APValue RefValue;
5237	if (!handleLValueToRValueConversion(this->Info, E, MD->getType(), Result,
5238	RefValue))
5239	return false;
5240	return Success(RefValue, E);
5241	}
5242	return true;
5243	}
5244
5245	bool VisitBinaryOperator(const BinaryOperator *E) {
5246	switch (E->getOpcode()) {
5247	default:
5248	return ExprEvaluatorBaseTy::VisitBinaryOperator(E);
5249
5250	case BO_PtrMemD:
5251	case BO_PtrMemI:
5252	return HandleMemberPointerAccess(this->Info, E, Result);
5253	}
5254	}
5255
5256	bool VisitCastExpr(const CastExpr *E) {
5257	switch (E->getCastKind()) {
5258	default:
5259	return ExprEvaluatorBaseTy::VisitCastExpr(E);
5260
5261	case CK_DerivedToBase:
5262	case CK_UncheckedDerivedToBase:
5263	if (!this->Visit(E->getSubExpr()))
5264	return false;
5265
5266	// Now figure out the necessary offset to add to the base LV to get from
5267	// the derived class to the base class.
5268	return HandleLValueBasePath(this->Info, E, E->getSubExpr()->getType(),
5269	Result);
5270	}
5271	}
5272	};
5273	}
5274
5275	//===----------------------------------------------------------------------===//
5276	// LValue Evaluation
5277	//
5278	// This is used for evaluating lvalues (in C and C++), xvalues (in C++11),
5279	// function designators (in C), decl references to void objects (in C), and
5280	// temporaries (if building with -Wno-address-of-temporary).
5281	//
5282	// LValue evaluation produces values comprising a base expression of one of the
5283	// following types:
5284	// - Declarations
5285	// * VarDecl
5286	// * FunctionDecl
5287	// - Literals
5288	// * CompoundLiteralExpr in C (and in global scope in C++)
5289	// * StringLiteral
5290	// * CXXTypeidExpr
5291	// * PredefinedExpr
5292	// * ObjCStringLiteralExpr
5293	// * ObjCEncodeExpr
5294	// * AddrLabelExpr
5295	// * BlockExpr
5296	// * CallExpr for a MakeStringConstant builtin
5297	// - Locals and temporaries
5298	// * MaterializeTemporaryExpr
5299	// * Any Expr, with a CallIndex indicating the function in which the temporary
5300	// was evaluated, for cases where the MaterializeTemporaryExpr is missing
5301	// from the AST (FIXME).
5302	// * A MaterializeTemporaryExpr that has static storage duration, with no
5303	// CallIndex, for a lifetime-extended temporary.
5304	// plus an offset in bytes.
5305	//===----------------------------------------------------------------------===//
5306	namespace {
5307	class LValueExprEvaluator
5308	: public LValueExprEvaluatorBase<LValueExprEvaluator> {
5309	public:
5310	LValueExprEvaluator(EvalInfo &Info, LValue &Result, bool InvalidBaseOK) :
5311	LValueExprEvaluatorBaseTy(Info, Result, InvalidBaseOK) {}
5312
5313	bool VisitVarDecl(const Expr E, const VarDecl VD);
5314	bool VisitUnaryPreIncDec(const UnaryOperator *UO);
5315
5316	bool VisitDeclRefExpr(const DeclRefExpr *E);
5317	bool VisitPredefinedExpr(const PredefinedExpr *E) { return Success(E); }
5318	bool VisitMaterializeTemporaryExpr(const MaterializeTemporaryExpr *E);
5319	bool VisitCompoundLiteralExpr(const CompoundLiteralExpr *E);
5320	bool VisitMemberExpr(const MemberExpr *E);
5321	bool VisitStringLiteral(const StringLiteral *E) { return Success(E); }
5322	bool VisitObjCEncodeExpr(const ObjCEncodeExpr *E) { return Success(E); }
5323	bool VisitCXXTypeidExpr(const CXXTypeidExpr *E);
5324	bool VisitCXXUuidofExpr(const CXXUuidofExpr *E);
5325	bool VisitArraySubscriptExpr(const ArraySubscriptExpr *E);
5326	bool VisitUnaryDeref(const UnaryOperator *E);
5327	bool VisitUnaryReal(const UnaryOperator *E);
5328	bool VisitUnaryImag(const UnaryOperator *E);
5329	bool VisitUnaryPreInc(const UnaryOperator *UO) {
5330	return VisitUnaryPreIncDec(UO);
5331	}
5332	bool VisitUnaryPreDec(const UnaryOperator *UO) {
5333	return VisitUnaryPreIncDec(UO);
5334	}
5335	bool VisitBinAssign(const BinaryOperator *BO);
5336	bool VisitCompoundAssignOperator(const CompoundAssignOperator *CAO);
5337
5338	bool VisitCastExpr(const CastExpr *E) {
5339	switch (E->getCastKind()) {
5340	default:
5341	return LValueExprEvaluatorBaseTy::VisitCastExpr(E);
5342
5343	case CK_LValueBitCast:
5344	this->CCEDiag(E, diag::note_constexpr_invalid_cast) << 2;
5345	if (!Visit(E->getSubExpr()))
5346	return false;
5347	Result.Designator.setInvalid();
5348	return true;
5349
5350	case CK_BaseToDerived:
5351	if (!Visit(E->getSubExpr()))
5352	return false;
5353	return HandleBaseToDerivedCast(Info, E, Result);
5354	}
5355	}
5356	};
5357	} // end anonymous namespace
5358
5359	/// Evaluate an expression as an lvalue. This can be legitimately called on
5360	/// expressions which are not glvalues, in three cases:
5361	/// * function designators in C, and
5362	/// * "extern void" objects
5363	/// * @selector() expressions in Objective-C
5364	static bool EvaluateLValue(const Expr *E, LValue &Result, EvalInfo &Info,
5365	bool InvalidBaseOK) {
5366	isGLValue() \|\| E->getType()->isFunctionType() \|\| E->getType()->isVoidType() \|\| isa(E)", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 5367, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(E->isGLValue() \|\| E->getType()->isFunctionType() \|\|
5367	isGLValue() \|\| E->getType()->isFunctionType() \|\| E->getType()->isVoidType() \|\| isa(E)", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 5367, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true"> E->getType()->isVoidType() \|\| isa<ObjCSelectorExpr>(E));
5368	return LValueExprEvaluator(Info, Result, InvalidBaseOK).Visit(E);
5369	}
5370
5371	bool LValueExprEvaluator::VisitDeclRefExpr(const DeclRefExpr *E) {
5372	if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(E->getDecl()))
5373	return Success(FD);
5374	if (const VarDecl *VD = dyn_cast<VarDecl>(E->getDecl()))
5375	return VisitVarDecl(E, VD);
5376	if (const BindingDecl *BD = dyn_cast<BindingDecl>(E->getDecl()))
5377	return Visit(BD->getBinding());
5378	return Error(E);
5379	}
5380
5381
5382	bool LValueExprEvaluator::VisitVarDecl(const Expr E, const VarDecl VD) {
5383
5384	// If we are within a lambda's call operator, check whether the 'VD' referred
5385	// to within 'E' actually represents a lambda-capture that maps to a
5386	// data-member/field within the closure object, and if so, evaluate to the
5387	// field or what the field refers to.
5388	if (Info.CurrentCall && isLambdaCallOperator(Info.CurrentCall->Callee) &&
5389	isa<DeclRefExpr>(E) &&
5390	cast<DeclRefExpr>(E)->refersToEnclosingVariableOrCapture()) {
5391	// We don't always have a complete capture-map when checking or inferring if
5392	// the function call operator meets the requirements of a constexpr function
5393	// - but we don't need to evaluate the captures to determine constexprness
5394	// (dcl.constexpr C++17).
5395	if (Info.checkingPotentialConstantExpression())
5396	return false;
5397
5398	if (auto *FD = Info.CurrentCall->LambdaCaptureFields.lookup(VD)) {
5399	// Start with 'Result' referring to the complete closure object...
5400	Result = *Info.CurrentCall->This;
5401	// ... then update it to refer to the field of the closure object
5402	// that represents the capture.
5403	if (!HandleLValueMember(Info, E, Result, FD))
5404	return false;
5405	// And if the field is of reference type, update 'Result' to refer to what
5406	// the field refers to.
5407	if (FD->getType()->isReferenceType()) {
5408	APValue RVal;
5409	if (!handleLValueToRValueConversion(Info, E, FD->getType(), Result,
5410	RVal))
5411	return false;
5412	Result.setFrom(Info.Ctx, RVal);
5413	}
5414	return true;
5415	}
5416	}
5417	CallStackFrame *Frame = nullptr;
5418	if (VD->hasLocalStorage() && Info.CurrentCall->Index > 1) {
5419	// Only if a local variable was declared in the function currently being
5420	// evaluated, do we expect to be able to find its value in the current
5421	// frame. (Otherwise it was likely declared in an enclosing context and
5422	// could either have a valid evaluatable value (for e.g. a constexpr
5423	// variable) or be ill-formed (and trigger an appropriate evaluation
5424	// diagnostic)).
5425	if (Info.CurrentCall->Callee &&
5426	Info.CurrentCall->Callee->Equals(VD->getDeclContext())) {
5427	Frame = Info.CurrentCall;
5428	}
5429	}
5430
5431	if (!VD->getType()->isReferenceType()) {
5432	if (Frame) {
5433	Result.set({VD, Frame->Index,
5434	Info.CurrentCall->getCurrentTemporaryVersion(VD)});
5435	return true;
5436	}
5437	return Success(VD);
5438	}
5439
5440	APValue *V;
5441	if (!evaluateVarDeclInit(Info, E, VD, Frame, V, nullptr))
5442	return false;
5443	if (V->isUninit()) {
5444	if (!Info.checkingPotentialConstantExpression())
5445	Info.FFDiag(E, diag::note_constexpr_use_uninit_reference);
5446	return false;
5447	}
5448	return Success(*V, E);
5449	}
5450
5451	bool LValueExprEvaluator::VisitMaterializeTemporaryExpr(
5452	const MaterializeTemporaryExpr *E) {
5453	// Walk through the expression to find the materialized temporary itself.
5454	SmallVector<const Expr *, 2> CommaLHSs;
5455	SmallVector<SubobjectAdjustment, 2> Adjustments;
5456	const Expr *Inner = E->GetTemporaryExpr()->
5457	skipRValueSubobjectAdjustments(CommaLHSs, Adjustments);
5458
5459	// If we passed any comma operators, evaluate their LHSs.
5460	for (unsigned I = 0, N = CommaLHSs.size(); I != N; ++I)
5461	if (!EvaluateIgnoredValue(Info, CommaLHSs[I]))
5462	return false;
5463
5464	// A materialized temporary with static storage duration can appear within the
5465	// result of a constant expression evaluation, so we need to preserve its
5466	// value for use outside this evaluation.
5467	APValue *Value;
5468	if (E->getStorageDuration() == SD_Static) {
5469	Value = Info.Ctx.getMaterializedTemporaryValue(E, true);
5470	*Value = APValue();
5471	Result.set(E);
5472	} else {
5473	Value = &createTemporary(E, E->getStorageDuration() == SD_Automatic, Result,
5474	*Info.CurrentCall);
5475	}
5476
5477	QualType Type = Inner->getType();
5478
5479	// Materialize the temporary itself.
5480	if (!EvaluateInPlace(*Value, Info, Result, Inner) \|\|
5481	(E->getStorageDuration() == SD_Static &&
5482	!CheckConstantExpression(Info, E->getExprLoc(), Type, *Value))) {
5483	*Value = APValue();
5484	return false;
5485	}
5486
5487	// Adjust our lvalue to refer to the desired subobject.
5488	for (unsigned I = Adjustments.size(); I != 0; /**/) {
5489	--I;
5490	switch (Adjustments[I].Kind) {
5491	case SubobjectAdjustment::DerivedToBaseAdjustment:
5492	if (!HandleLValueBasePath(Info, Adjustments[I].DerivedToBase.BasePath,
5493	Type, Result))
5494	return false;
5495	Type = Adjustments[I].DerivedToBase.BasePath->getType();
5496	break;
5497
5498	case SubobjectAdjustment::FieldAdjustment:
5499	if (!HandleLValueMember(Info, E, Result, Adjustments[I].Field))
5500	return false;
5501	Type = Adjustments[I].Field->getType();
5502	break;
5503
5504	case SubobjectAdjustment::MemberPointerAdjustment:
5505	if (!HandleMemberPointerAccess(this->Info, Type, Result,
5506	Adjustments[I].Ptr.RHS))
5507	return false;
5508	Type = Adjustments[I].Ptr.MPT->getPointeeType();
5509	break;
5510	}
5511	}
5512
5513	return true;
5514	}
5515
5516	bool
5517	LValueExprEvaluator::VisitCompoundLiteralExpr(const CompoundLiteralExpr *E) {
5518	(0) . __assert_fail ("(!Info.getLangOpts().CPlusPlus \|\| E->isFileScope()) && \"lvalue compound literal in c++?\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 5519, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert((!Info.getLangOpts().CPlusPlus \|\| E->isFileScope()) &&
5519	(0) . __assert_fail ("(!Info.getLangOpts().CPlusPlus \|\| E->isFileScope()) && \"lvalue compound literal in c++?\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 5519, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true"> "lvalue compound literal in c++?");
5520	// Defer visiting the literal until the lvalue-to-rvalue conversion. We can
5521	// only see this when folding in C, so there's no standard to follow here.
5522	return Success(E);
5523	}
5524
5525	bool LValueExprEvaluator::VisitCXXTypeidExpr(const CXXTypeidExpr *E) {
5526	if (!E->isPotentiallyEvaluated())
5527	return Success(E);
5528
5529	Info.FFDiag(E, diag::note_constexpr_typeid_polymorphic)
5530	<< E->getExprOperand()->getType()
5531	<< E->getExprOperand()->getSourceRange();
5532	return false;
5533	}
5534
5535	bool LValueExprEvaluator::VisitCXXUuidofExpr(const CXXUuidofExpr *E) {
5536	return Success(E);
5537	}
5538
5539	bool LValueExprEvaluator::VisitMemberExpr(const MemberExpr *E) {
5540	// Handle static data members.
5541	if (const VarDecl *VD = dyn_cast<VarDecl>(E->getMemberDecl())) {
5542	VisitIgnoredBaseExpression(E->getBase());
5543	return VisitVarDecl(E, VD);
5544	}
5545
5546	// Handle static member functions.
5547	if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(E->getMemberDecl())) {
5548	if (MD->isStatic()) {
5549	VisitIgnoredBaseExpression(E->getBase());
5550	return Success(MD);
5551	}
5552	}
5553
5554	// Handle non-static data members.
5555	return LValueExprEvaluatorBaseTy::VisitMemberExpr(E);
5556	}
5557
5558	bool LValueExprEvaluator::VisitArraySubscriptExpr(const ArraySubscriptExpr *E) {
5559	// FIXME: Deal with vectors as array subscript bases.
5560	if (E->getBase()->getType()->isVectorType())
5561	return Error(E);
5562
5563	bool Success = true;
5564	if (!evaluatePointer(E->getBase(), Result)) {
5565	if (!Info.noteFailure())
5566	return false;
5567	Success = false;
5568	}
5569
5570	APSInt Index;
5571	if (!EvaluateInteger(E->getIdx(), Index, Info))
5572	return false;
5573
5574	return Success &&
5575	HandleLValueArrayAdjustment(Info, E, Result, E->getType(), Index);
5576	}
5577
5578	bool LValueExprEvaluator::VisitUnaryDeref(const UnaryOperator *E) {
5579	return evaluatePointer(E->getSubExpr(), Result);
5580	}
5581
5582	bool LValueExprEvaluator::VisitUnaryReal(const UnaryOperator *E) {
5583	if (!Visit(E->getSubExpr()))
5584	return false;
5585	// __real is a no-op on scalar lvalues.
5586	if (E->getSubExpr()->getType()->isAnyComplexType())
5587	HandleLValueComplexElement(Info, E, Result, E->getType(), false);
5588	return true;
5589	}
5590
5591	bool LValueExprEvaluator::VisitUnaryImag(const UnaryOperator *E) {
5592	(0) . __assert_fail ("E->getSubExpr()->getType()->isAnyComplexType() && \"lvalue __imag__ on scalar?\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 5593, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(E->getSubExpr()->getType()->isAnyComplexType() &&
5593	(0) . __assert_fail ("E->getSubExpr()->getType()->isAnyComplexType() && \"lvalue __imag__ on scalar?\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 5593, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true"> "lvalue __imag__ on scalar?");
5594	if (!Visit(E->getSubExpr()))
5595	return false;
5596	HandleLValueComplexElement(Info, E, Result, E->getType(), true);
5597	return true;
5598	}
5599
5600	bool LValueExprEvaluator::VisitUnaryPreIncDec(const UnaryOperator *UO) {
5601	if (!Info.getLangOpts().CPlusPlus14 && !Info.keepEvaluatingAfterFailure())
5602	return Error(UO);
5603
5604	if (!this->Visit(UO->getSubExpr()))
5605	return false;
5606
5607	return handleIncDec(
5608	this->Info, UO, Result, UO->getSubExpr()->getType(),
5609	UO->isIncrementOp(), nullptr);
5610	}
5611
5612	bool LValueExprEvaluator::VisitCompoundAssignOperator(
5613	const CompoundAssignOperator *CAO) {
5614	if (!Info.getLangOpts().CPlusPlus14 && !Info.keepEvaluatingAfterFailure())
5615	return Error(CAO);
5616
5617	APValue RHS;
5618
5619	// The overall lvalue result is the result of evaluating the LHS.
5620	if (!this->Visit(CAO->getLHS())) {
5621	if (Info.noteFailure())
5622	Evaluate(RHS, this->Info, CAO->getRHS());
5623	return false;
5624	}
5625
5626	if (!Evaluate(RHS, this->Info, CAO->getRHS()))
5627	return false;
5628
5629	return handleCompoundAssignment(
5630	this->Info, CAO,
5631	Result, CAO->getLHS()->getType(), CAO->getComputationLHSType(),
5632	CAO->getOpForCompoundAssignment(CAO->getOpcode()), RHS);
5633	}
5634
5635	bool LValueExprEvaluator::VisitBinAssign(const BinaryOperator *E) {
5636	if (!Info.getLangOpts().CPlusPlus14 && !Info.keepEvaluatingAfterFailure())
5637	return Error(E);
5638
5639	APValue NewVal;
5640
5641	if (!this->Visit(E->getLHS())) {
5642	if (Info.noteFailure())
5643	Evaluate(NewVal, this->Info, E->getRHS());
5644	return false;
5645	}
5646
5647	if (!Evaluate(NewVal, this->Info, E->getRHS()))
5648	return false;
5649
5650	return handleAssignment(this->Info, E, Result, E->getLHS()->getType(),
5651	NewVal);
5652	}
5653
5654	//===----------------------------------------------------------------------===//
5655	// Pointer Evaluation
5656	//===----------------------------------------------------------------------===//
5657
5658	/// Attempts to compute the number of bytes available at the pointer
5659	/// returned by a function with the alloc_size attribute. Returns true if we
5660	/// were successful. Places an unsigned number into `Result`.
5661	///
5662	/// This expects the given CallExpr to be a call to a function with an
5663	/// alloc_size attribute.
5664	static bool getBytesReturnedByAllocSizeCall(const ASTContext &Ctx,
5665	const CallExpr *Call,
5666	llvm::APInt &Result) {
5667	const AllocSizeAttr *AllocSize = getAllocSizeAttr(Call);
5668
5669	getElemSizeParam().isValid()", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 5669, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(AllocSize && AllocSize->getElemSizeParam().isValid());
5670	unsigned SizeArgNo = AllocSize->getElemSizeParam().getASTIndex();
5671	unsigned BitsInSizeT = Ctx.getTypeSize(Ctx.getSizeType());
5672	if (Call->getNumArgs() <= SizeArgNo)
5673	return false;
5674
5675	auto EvaluateAsSizeT = [&](const Expr *E, APSInt &Into) {
5676	Expr::EvalResult ExprResult;
5677	if (!E->EvaluateAsInt(ExprResult, Ctx, Expr::SE_AllowSideEffects))
5678	return false;
5679	Into = ExprResult.Val.getInt();
5680	if (Into.isNegative() \|\| !Into.isIntN(BitsInSizeT))
5681	return false;
5682	Into = Into.zextOrSelf(BitsInSizeT);
5683	return true;
5684	};
5685
5686	APSInt SizeOfElem;
5687	if (!EvaluateAsSizeT(Call->getArg(SizeArgNo), SizeOfElem))
5688	return false;
5689
5690	if (!AllocSize->getNumElemsParam().isValid()) {
5691	Result = std::move(SizeOfElem);
5692	return true;
5693	}
5694
5695	APSInt NumberOfElems;
5696	unsigned NumArgNo = AllocSize->getNumElemsParam().getASTIndex();
5697	if (!EvaluateAsSizeT(Call->getArg(NumArgNo), NumberOfElems))
5698	return false;
5699
5700	bool Overflow;
5701	llvm::APInt BytesAvailable = SizeOfElem.umul_ov(NumberOfElems, Overflow);
5702	if (Overflow)
5703	return false;
5704
5705	Result = std::move(BytesAvailable);
5706	return true;
5707	}
5708
5709	/// Convenience function. LVal's base must be a call to an alloc_size
5710	/// function.
5711	static bool getBytesReturnedByAllocSizeCall(const ASTContext &Ctx,
5712	const LValue &LVal,
5713	llvm::APInt &Result) {
5714	(0) . __assert_fail ("isBaseAnAllocSizeCall(LVal.getLValueBase()) && \"Can't get the size of a non alloc_size function\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 5715, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(isBaseAnAllocSizeCall(LVal.getLValueBase()) &&
5715	(0) . __assert_fail ("isBaseAnAllocSizeCall(LVal.getLValueBase()) && \"Can't get the size of a non alloc_size function\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 5715, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true"> "Can't get the size of a non alloc_size function");
5716	const auto Base = LVal.getLValueBase().get<const Expr >();
5717	const CallExpr *CE = tryUnwrapAllocSizeCall(Base);
5718	return getBytesReturnedByAllocSizeCall(Ctx, CE, Result);
5719	}
5720
5721	/// Attempts to evaluate the given LValueBase as the result of a call to
5722	/// a function with the alloc_size attribute. If it was possible to do so, this
5723	/// function will return true, make Result's Base point to said function call,
5724	/// and mark Result's Base as invalid.
5725	static bool evaluateLValueAsAllocSize(EvalInfo &Info, APValue::LValueBase Base,
5726	LValue &Result) {
5727	if (Base.isNull())
5728	return false;
5729
5730	// Because we do no form of static analysis, we only support const variables.
5731	//
5732	// Additionally, we can't support parameters, nor can we support static
5733	// variables (in the latter case, use-before-assign isn't UB; in the former,
5734	// we have no clue what they'll be assigned to).
5735	const auto *VD =
5736	dyn_cast_or_null<VarDecl>(Base.dyn_cast<const ValueDecl *>());
5737	if (!VD \|\| !VD->isLocalVarDecl() \|\| !VD->getType().isConstQualified())
5738	return false;
5739
5740	const Expr *Init = VD->getAnyInitializer();
5741	if (!Init)
5742	return false;
5743
5744	const Expr *E = Init->IgnoreParens();
5745	if (!tryUnwrapAllocSizeCall(E))
5746	return false;
5747
5748	// Store E instead of E unwrapped so that the type of the LValue's base is
5749	// what the user wanted.
5750	Result.setInvalid(E);
5751
5752	QualType Pointee = E->getType()->castAs<PointerType>()->getPointeeType();
5753	Result.addUnsizedArray(Info, E, Pointee);
5754	return true;
5755	}
5756
5757	namespace {
5758	class PointerExprEvaluator
5759	: public ExprEvaluatorBase<PointerExprEvaluator> {
5760	LValue &Result;
5761	bool InvalidBaseOK;
5762
5763	bool Success(const Expr *E) {
5764	Result.set(E);
5765	return true;
5766	}
5767
5768	bool evaluateLValue(const Expr *E, LValue &Result) {
5769	return EvaluateLValue(E, Result, Info, InvalidBaseOK);
5770	}
5771
5772	bool evaluatePointer(const Expr *E, LValue &Result) {
5773	return EvaluatePointer(E, Result, Info, InvalidBaseOK);
5774	}
5775
5776	bool visitNonBuiltinCallExpr(const CallExpr *E);
5777	public:
5778
5779	PointerExprEvaluator(EvalInfo &info, LValue &Result, bool InvalidBaseOK)
5780	: ExprEvaluatorBaseTy(info), Result(Result),
5781	InvalidBaseOK(InvalidBaseOK) {}
5782
5783	bool Success(const APValue &V, const Expr *E) {
5784	Result.setFrom(Info.Ctx, V);
5785	return true;
5786	}
5787	bool ZeroInitialization(const Expr *E) {
5788	auto TargetVal = Info.Ctx.getTargetNullPointerValue(E->getType());
5789	Result.setNull(E->getType(), TargetVal);
5790	return true;
5791	}
5792
5793	bool VisitBinaryOperator(const BinaryOperator *E);
5794	bool VisitCastExpr(const CastExpr* E);
5795	bool VisitUnaryAddrOf(const UnaryOperator *E);
5796	bool VisitObjCStringLiteral(const ObjCStringLiteral *E)
5797	{ return Success(E); }
5798	bool VisitObjCBoxedExpr(const ObjCBoxedExpr *E) {
5799	if (E->isExpressibleAsConstantInitializer())
5800	return Success(E);
5801	if (Info.noteFailure())
5802	EvaluateIgnoredValue(Info, E->getSubExpr());
5803	return Error(E);
5804	}
5805	bool VisitAddrLabelExpr(const AddrLabelExpr *E)
5806	{ return Success(E); }
5807	bool VisitCallExpr(const CallExpr *E);
5808	bool VisitBuiltinCallExpr(const CallExpr *E, unsigned BuiltinOp);
5809	bool VisitBlockExpr(const BlockExpr *E) {
5810	if (!E->getBlockDecl()->hasCaptures())
5811	return Success(E);
5812	return Error(E);
5813	}
5814	bool VisitCXXThisExpr(const CXXThisExpr *E) {
5815	// Can't look at 'this' when checking a potential constant expression.
5816	if (Info.checkingPotentialConstantExpression())
5817	return false;
5818	if (!Info.CurrentCall->This) {
5819	if (Info.getLangOpts().CPlusPlus11)
5820	Info.FFDiag(E, diag::note_constexpr_this) << E->isImplicit();
5821	else
5822	Info.FFDiag(E);
5823	return false;
5824	}
5825	Result = *Info.CurrentCall->This;
5826	// If we are inside a lambda's call operator, the 'this' expression refers
5827	// to the enclosing '*this' object (either by value or reference) which is
5828	// either copied into the closure object's field that represents the '*this'
5829	// or refers to '*this'.
5830	if (isLambdaCallOperator(Info.CurrentCall->Callee)) {
5831	// Update 'Result' to refer to the data member/field of the closure object
5832	// that represents the '*this' capture.
5833	if (!HandleLValueMember(Info, E, Result,
5834	Info.CurrentCall->LambdaThisCaptureField))
5835	return false;
5836	// If we captured '*this' by reference, replace the field with its referent.
5837	if (Info.CurrentCall->LambdaThisCaptureField->getType()
5838	->isPointerType()) {
5839	APValue RVal;
5840	if (!handleLValueToRValueConversion(Info, E, E->getType(), Result,
5841	RVal))
5842	return false;
5843
5844	Result.setFrom(Info.Ctx, RVal);
5845	}
5846	}
5847	return true;
5848	}
5849
5850	// FIXME: Missing: @protocol, @selector
5851	};
5852	} // end anonymous namespace
5853
5854	static bool EvaluatePointer(const Expr* E, LValue& Result, EvalInfo &Info,
5855	bool InvalidBaseOK) {
5856	isRValue() && E->getType()->hasPointerRepresentation()", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 5856, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(E->isRValue() && E->getType()->hasPointerRepresentation());
5857	return PointerExprEvaluator(Info, Result, InvalidBaseOK).Visit(E);
5858	}
5859
5860	bool PointerExprEvaluator::VisitBinaryOperator(const BinaryOperator *E) {
5861	if (E->getOpcode() != BO_Add &&
5862	E->getOpcode() != BO_Sub)
5863	return ExprEvaluatorBaseTy::VisitBinaryOperator(E);
5864
5865	const Expr *PExp = E->getLHS();
5866	const Expr *IExp = E->getRHS();
5867	if (IExp->getType()->isPointerType())
5868	std::swap(PExp, IExp);
5869
5870	bool EvalPtrOK = evaluatePointer(PExp, Result);
5871	if (!EvalPtrOK && !Info.noteFailure())
5872	return false;
5873
5874	llvm::APSInt Offset;
5875	if (!EvaluateInteger(IExp, Offset, Info) \|\| !EvalPtrOK)
5876	return false;
5877
5878	if (E->getOpcode() == BO_Sub)
5879	negateAsSigned(Offset);
5880
5881	QualType Pointee = PExp->getType()->castAs<PointerType>()->getPointeeType();
5882	return HandleLValueArrayAdjustment(Info, E, Result, Pointee, Offset);
5883	}
5884
5885	bool PointerExprEvaluator::VisitUnaryAddrOf(const UnaryOperator *E) {
5886	return evaluateLValue(E->getSubExpr(), Result);
5887	}
5888
5889	bool PointerExprEvaluator::VisitCastExpr(const CastExpr *E) {
5890	const Expr *SubExpr = E->getSubExpr();
5891
5892	switch (E->getCastKind()) {
5893	default:
5894	break;
5895
5896	case CK_BitCast:
5897	case CK_CPointerToObjCPointerCast:
5898	case CK_BlockPointerToObjCPointerCast:
5899	case CK_AnyPointerToBlockPointerCast:
5900	case CK_AddressSpaceConversion:
5901	if (!Visit(SubExpr))
5902	return false;
5903	// Bitcasts to cv void* are static_casts, not reinterpret_casts, so are
5904	// permitted in constant expressions in C++11. Bitcasts from cv void* are
5905	// also static_casts, but we disallow them as a resolution to DR1312.
5906	if (!E->getType()->isVoidPointerType()) {
5907	Result.Designator.setInvalid();
5908	if (SubExpr->getType()->isVoidPointerType())
5909	CCEDiag(E, diag::note_constexpr_invalid_cast)
5910	<< 3 << SubExpr->getType();
5911	else
5912	CCEDiag(E, diag::note_constexpr_invalid_cast) << 2;
5913	}
5914	if (E->getCastKind() == CK_AddressSpaceConversion && Result.IsNullPtr)
5915	ZeroInitialization(E);
5916	return true;
5917
5918	case CK_DerivedToBase:
5919	case CK_UncheckedDerivedToBase:
5920	if (!evaluatePointer(E->getSubExpr(), Result))
5921	return false;
5922	if (!Result.Base && Result.Offset.isZero())
5923	return true;
5924
5925	// Now figure out the necessary offset to add to the base LV to get from
5926	// the derived class to the base class.
5927	return HandleLValueBasePath(Info, E, E->getSubExpr()->getType()->
5928	castAs<PointerType>()->getPointeeType(),
5929	Result);
5930
5931	case CK_BaseToDerived:
5932	if (!Visit(E->getSubExpr()))
5933	return false;
5934	if (!Result.Base && Result.Offset.isZero())
5935	return true;
5936	return HandleBaseToDerivedCast(Info, E, Result);
5937
5938	case CK_NullToPointer:
5939	VisitIgnoredValue(E->getSubExpr());
5940	return ZeroInitialization(E);
5941
5942	case CK_IntegralToPointer: {
5943	CCEDiag(E, diag::note_constexpr_invalid_cast) << 2;
5944
5945	APValue Value;
5946	if (!EvaluateIntegerOrLValue(SubExpr, Value, Info))
5947	break;
5948
5949	if (Value.isInt()) {
5950	unsigned Size = Info.Ctx.getTypeSize(E->getType());
5951	uint64_t N = Value.getInt().extOrTrunc(Size).getZExtValue();
5952	Result.Base = (Expr*)nullptr;
5953	Result.InvalidBase = false;
5954	Result.Offset = CharUnits::fromQuantity(N);
5955	Result.Designator.setInvalid();
5956	Result.IsNullPtr = false;
5957	return true;
5958	} else {
5959	// Cast is of an lvalue, no need to change value.
5960	Result.setFrom(Info.Ctx, Value);
5961	return true;
5962	}
5963	}
5964
5965	case CK_ArrayToPointerDecay: {
5966	if (SubExpr->isGLValue()) {
5967	if (!evaluateLValue(SubExpr, Result))
5968	return false;
5969	} else {
5970	APValue &Value = createTemporary(SubExpr, false, Result,
5971	*Info.CurrentCall);
5972	if (!EvaluateInPlace(Value, Info, Result, SubExpr))
5973	return false;
5974	}
5975	// The result is a pointer to the first element of the array.
5976	auto *AT = Info.Ctx.getAsArrayType(SubExpr->getType());
5977	if (auto *CAT = dyn_cast<ConstantArrayType>(AT))
5978	Result.addArray(Info, E, CAT);
5979	else
5980	Result.addUnsizedArray(Info, E, AT->getElementType());
5981	return true;
5982	}
5983
5984	case CK_FunctionToPointerDecay:
5985	return evaluateLValue(SubExpr, Result);
5986
5987	case CK_LValueToRValue: {
5988	LValue LVal;
5989	if (!evaluateLValue(E->getSubExpr(), LVal))
5990	return false;
5991
5992	APValue RVal;
5993	// Note, we use the subexpression's type in order to retain cv-qualifiers.
5994	if (!handleLValueToRValueConversion(Info, E, E->getSubExpr()->getType(),
5995	LVal, RVal))
5996	return InvalidBaseOK &&
5997	evaluateLValueAsAllocSize(Info, LVal.Base, Result);
5998	return Success(RVal, E);
5999	}
6000	}
6001
6002	return ExprEvaluatorBaseTy::VisitCastExpr(E);
6003	}
6004
6005	static CharUnits GetAlignOfType(EvalInfo &Info, QualType T,
6006	UnaryExprOrTypeTrait ExprKind) {
6007	// C++ [expr.alignof]p3:
6008	// When alignof is applied to a reference type, the result is the
6009	// alignment of the referenced type.
6010	if (const ReferenceType *Ref = T->getAs<ReferenceType>())
6011	T = Ref->getPointeeType();
6012
6013	if (T.getQualifiers().hasUnaligned())
6014	return CharUnits::One();
6015
6016	const bool AlignOfReturnsPreferred =
6017	Info.Ctx.getLangOpts().getClangABICompat() <= LangOptions::ClangABI::Ver7;
6018
6019	// __alignof is defined to return the preferred alignment.
6020	// Before 8, clang returned the preferred alignment for alignof and _Alignof
6021	// as well.
6022	if (ExprKind == UETT_PreferredAlignOf \|\| AlignOfReturnsPreferred)
6023	return Info.Ctx.toCharUnitsFromBits(
6024	Info.Ctx.getPreferredTypeAlign(T.getTypePtr()));
6025	// alignof and _Alignof are defined to return the ABI alignment.
6026	else if (ExprKind == UETT_AlignOf)
6027	return Info.Ctx.getTypeAlignInChars(T.getTypePtr());
6028	else
6029	llvm_unreachable("GetAlignOfType on a non-alignment ExprKind");
6030	}
6031
6032	static CharUnits GetAlignOfExpr(EvalInfo &Info, const Expr *E,
6033	UnaryExprOrTypeTrait ExprKind) {
6034	E = E->IgnoreParens();
6035
6036	// The kinds of expressions that we have special-case logic here for
6037	// should be kept up to date with the special checks for those
6038	// expressions in Sema.
6039
6040	// alignof decl is always accepted, even if it doesn't make sense: we default
6041	// to 1 in those cases.
6042	if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E))
6043	return Info.Ctx.getDeclAlign(DRE->getDecl(),
6044	/RefAsPointee/true);
6045
6046	if (const MemberExpr *ME = dyn_cast<MemberExpr>(E))
6047	return Info.Ctx.getDeclAlign(ME->getMemberDecl(),
6048	/RefAsPointee/true);
6049
6050	return GetAlignOfType(Info, E->getType(), ExprKind);
6051	}
6052
6053	// To be clear: this happily visits unsupported builtins. Better name welcomed.
6054	bool PointerExprEvaluator::visitNonBuiltinCallExpr(const CallExpr *E) {
6055	if (ExprEvaluatorBaseTy::VisitCallExpr(E))
6056	return true;
6057
6058	if (!(InvalidBaseOK && getAllocSizeAttr(E)))
6059	return false;
6060
6061	Result.setInvalid(E);
6062	QualType PointeeTy = E->getType()->castAs<PointerType>()->getPointeeType();
6063	Result.addUnsizedArray(Info, E, PointeeTy);
6064	return true;
6065	}
6066
6067	bool PointerExprEvaluator::VisitCallExpr(const CallExpr *E) {
6068	if (IsStringLiteralCall(E))
6069	return Success(E);
6070
6071	if (unsigned BuiltinOp = E->getBuiltinCallee())
6072	return VisitBuiltinCallExpr(E, BuiltinOp);
6073
6074	return visitNonBuiltinCallExpr(E);
6075	}
6076
6077	bool PointerExprEvaluator::VisitBuiltinCallExpr(const CallExpr *E,
6078	unsigned BuiltinOp) {
6079	switch (BuiltinOp) {
6080	case Builtin::BI__builtin_addressof:
6081	return evaluateLValue(E->getArg(0), Result);
6082	case Builtin::BI__builtin_assume_aligned: {
6083	// We need to be very careful here because: if the pointer does not have the
6084	// asserted alignment, then the behavior is undefined, and undefined
6085	// behavior is non-constant.
6086	if (!evaluatePointer(E->getArg(0), Result))
6087	return false;
6088
6089	LValue OffsetResult(Result);
6090	APSInt Alignment;
6091	if (!EvaluateInteger(E->getArg(1), Alignment, Info))
6092	return false;
6093	CharUnits Align = CharUnits::fromQuantity(Alignment.getZExtValue());
6094
6095	if (E->getNumArgs() > 2) {
6096	APSInt Offset;
6097	if (!EvaluateInteger(E->getArg(2), Offset, Info))
6098	return false;
6099
6100	int64_t AdditionalOffset = -Offset.getZExtValue();
6101	OffsetResult.Offset += CharUnits::fromQuantity(AdditionalOffset);
6102	}
6103
6104	// If there is a base object, then it must have the correct alignment.
6105	if (OffsetResult.Base) {
6106	CharUnits BaseAlignment;
6107	if (const ValueDecl *VD =
6108	OffsetResult.Base.dyn_cast<const ValueDecl*>()) {
6109	BaseAlignment = Info.Ctx.getDeclAlign(VD);
6110	} else {
6111	BaseAlignment = GetAlignOfExpr(
6112	Info, OffsetResult.Base.get<const Expr *>(), UETT_AlignOf);
6113	}
6114
6115	if (BaseAlignment < Align) {
6116	Result.Designator.setInvalid();
6117	// FIXME: Add support to Diagnostic for long / long long.
6118	CCEDiag(E->getArg(0),
6119	diag::note_constexpr_baa_insufficient_alignment) << 0
6120	<< (unsigned)BaseAlignment.getQuantity()
6121	<< (unsigned)Align.getQuantity();
6122	return false;
6123	}
6124	}
6125
6126	// The offset must also have the correct alignment.
6127	if (OffsetResult.Offset.alignTo(Align) != OffsetResult.Offset) {
6128	Result.Designator.setInvalid();
6129
6130	(OffsetResult.Base
6131	? CCEDiag(E->getArg(0),
6132	diag::note_constexpr_baa_insufficient_alignment) << 1
6133	: CCEDiag(E->getArg(0),
6134	diag::note_constexpr_baa_value_insufficient_alignment))
6135	<< (int)OffsetResult.Offset.getQuantity()
6136	<< (unsigned)Align.getQuantity();
6137	return false;
6138	}
6139
6140	return true;
6141	}
6142	case Builtin::BI__builtin_launder:
6143	return evaluatePointer(E->getArg(0), Result);
6144	case Builtin::BIstrchr:
6145	case Builtin::BIwcschr:
6146	case Builtin::BImemchr:
6147	case Builtin::BIwmemchr:
6148	if (Info.getLangOpts().CPlusPlus11)
6149	Info.CCEDiag(E, diag::note_constexpr_invalid_function)
6150	<< /isConstexpr/0 << /isConstructor/0
6151	<< (std::string("'") + Info.Ctx.BuiltinInfo.getName(BuiltinOp) + "'");
6152	else
6153	Info.CCEDiag(E, diag::note_invalid_subexpr_in_const_expr);
6154	LLVM_FALLTHROUGH;
6155	case Builtin::BI__builtin_strchr:
6156	case Builtin::BI__builtin_wcschr:
6157	case Builtin::BI__builtin_memchr:
6158	case Builtin::BI__builtin_char_memchr:
6159	case Builtin::BI__builtin_wmemchr: {
6160	if (!Visit(E->getArg(0)))
6161	return false;
6162	APSInt Desired;
6163	if (!EvaluateInteger(E->getArg(1), Desired, Info))
6164	return false;
6165	uint64_t MaxLength = uint64_t(-1);
6166	if (BuiltinOp != Builtin::BIstrchr &&
6167	BuiltinOp != Builtin::BIwcschr &&
6168	BuiltinOp != Builtin::BI__builtin_strchr &&
6169	BuiltinOp != Builtin::BI__builtin_wcschr) {
6170	APSInt N;
6171	if (!EvaluateInteger(E->getArg(2), N, Info))
6172	return false;
6173	MaxLength = N.getExtValue();
6174	}
6175	// We cannot find the value if there are no candidates to match against.
6176	if (MaxLength == 0u)
6177	return ZeroInitialization(E);
6178	if (!Result.checkNullPointerForFoldAccess(Info, E, AK_Read) \|\|
6179	Result.Designator.Invalid)
6180	return false;
6181	QualType CharTy = Result.Designator.getType(Info.Ctx);
6182	bool IsRawByte = BuiltinOp == Builtin::BImemchr \|\|
6183	BuiltinOp == Builtin::BI__builtin_memchr;
6184	getArg(0)->getType()->getPointeeType())", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 6186, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(IsRawByte \|\|
6185	getArg(0)->getType()->getPointeeType())", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 6186, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true"> Info.Ctx.hasSameUnqualifiedType(
6186	getArg(0)->getType()->getPointeeType())", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 6186, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true"> CharTy, E->getArg(0)->getType()->getPointeeType()));
6187	// Pointers to const void may point to objects of incomplete type.
6188	if (IsRawByte && CharTy->isIncompleteType()) {
6189	Info.FFDiag(E, diag::note_constexpr_ltor_incomplete_type) << CharTy;
6190	return false;
6191	}
6192	// Give up on byte-oriented matching against multibyte elements.
6193	// FIXME: We can compare the bytes in the correct order.
6194	if (IsRawByte && Info.Ctx.getTypeSizeInChars(CharTy) != CharUnits::One())
6195	return false;
6196	// Figure out what value we're actually looking for (after converting to
6197	// the corresponding unsigned type if necessary).
6198	uint64_t DesiredVal;
6199	bool StopAtNull = false;
6200	switch (BuiltinOp) {
6201	case Builtin::BIstrchr:
6202	case Builtin::BI__builtin_strchr:
6203	// strchr compares directly to the passed integer, and therefore
6204	// always fails if given an int that is not a char.
6205	if (!APSInt::isSameValue(HandleIntToIntCast(Info, E, CharTy,
6206	E->getArg(1)->getType(),
6207	Desired),
6208	Desired))
6209	return ZeroInitialization(E);
6210	StopAtNull = true;
6211	LLVM_FALLTHROUGH;
6212	case Builtin::BImemchr:
6213	case Builtin::BI__builtin_memchr:
6214	case Builtin::BI__builtin_char_memchr:
6215	// memchr compares by converting both sides to unsigned char. That's also
6216	// correct for strchr if we get this far (to cope with plain char being
6217	// unsigned in the strchr case).
6218	DesiredVal = Desired.trunc(Info.Ctx.getCharWidth()).getZExtValue();
6219	break;
6220
6221	case Builtin::BIwcschr:
6222	case Builtin::BI__builtin_wcschr:
6223	StopAtNull = true;
6224	LLVM_FALLTHROUGH;
6225	case Builtin::BIwmemchr:
6226	case Builtin::BI__builtin_wmemchr:
6227	// wcschr and wmemchr are given a wchar_t to look for. Just use it.
6228	DesiredVal = Desired.getZExtValue();
6229	break;
6230	}
6231
6232	for (; MaxLength; --MaxLength) {
6233	APValue Char;
6234	if (!handleLValueToRValueConversion(Info, E, CharTy, Result, Char) \|\|
6235	!Char.isInt())
6236	return false;
6237	if (Char.getInt().getZExtValue() == DesiredVal)
6238	return true;
6239	if (StopAtNull && !Char.getInt())
6240	break;
6241	if (!HandleLValueArrayAdjustment(Info, E, Result, CharTy, 1))
6242	return false;
6243	}
6244	// Not found: return nullptr.
6245	return ZeroInitialization(E);
6246	}
6247
6248	case Builtin::BImemcpy:
6249	case Builtin::BImemmove:
6250	case Builtin::BIwmemcpy:
6251	case Builtin::BIwmemmove:
6252	if (Info.getLangOpts().CPlusPlus11)
6253	Info.CCEDiag(E, diag::note_constexpr_invalid_function)
6254	<< /isConstexpr/0 << /isConstructor/0
6255	<< (std::string("'") + Info.Ctx.BuiltinInfo.getName(BuiltinOp) + "'");
6256	else
6257	Info.CCEDiag(E, diag::note_invalid_subexpr_in_const_expr);
6258	LLVM_FALLTHROUGH;
6259	case Builtin::BI__builtin_memcpy:
6260	case Builtin::BI__builtin_memmove:
6261	case Builtin::BI__builtin_wmemcpy:
6262	case Builtin::BI__builtin_wmemmove: {
6263	bool WChar = BuiltinOp == Builtin::BIwmemcpy \|\|
6264	BuiltinOp == Builtin::BIwmemmove \|\|
6265	BuiltinOp == Builtin::BI__builtin_wmemcpy \|\|
6266	BuiltinOp == Builtin::BI__builtin_wmemmove;
6267	bool Move = BuiltinOp == Builtin::BImemmove \|\|
6268	BuiltinOp == Builtin::BIwmemmove \|\|
6269	BuiltinOp == Builtin::BI__builtin_memmove \|\|
6270	BuiltinOp == Builtin::BI__builtin_wmemmove;
6271
6272	// The result of mem* is the first argument.
6273	if (!Visit(E->getArg(0)))
6274	return false;
6275	LValue Dest = Result;
6276
6277	LValue Src;
6278	if (!EvaluatePointer(E->getArg(1), Src, Info))
6279	return false;
6280
6281	APSInt N;
6282	if (!EvaluateInteger(E->getArg(2), N, Info))
6283	return false;
6284	(0) . __assert_fail ("!N.isSigned() && \"memcpy and friends take an unsigned size\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 6284, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(!N.isSigned() && "memcpy and friends take an unsigned size");
6285
6286	// If the size is zero, we treat this as always being a valid no-op.
6287	// (Even if one of the src and dest pointers is null.)
6288	if (!N)
6289	return true;
6290
6291	// Otherwise, if either of the operands is null, we can't proceed. Don't
6292	// try to determine the type of the copied objects, because there aren't
6293	// any.
6294	if (!Src.Base \|\| !Dest.Base) {
6295	APValue Val;
6296	(!Src.Base ? Src : Dest).moveInto(Val);
6297	Info.FFDiag(E, diag::note_constexpr_memcpy_null)
6298	<< Move << WChar << !!Src.Base
6299	<< Val.getAsString(Info.Ctx, E->getArg(0)->getType());
6300	return false;
6301	}
6302	if (Src.Designator.Invalid \|\| Dest.Designator.Invalid)
6303	return false;
6304
6305	// We require that Src and Dest are both pointers to arrays of
6306	// trivially-copyable type. (For the wide version, the designator will be
6307	// invalid if the designated object is not a wchar_t.)
6308	QualType T = Dest.Designator.getType(Info.Ctx);
6309	QualType SrcT = Src.Designator.getType(Info.Ctx);
6310	if (!Info.Ctx.hasSameUnqualifiedType(T, SrcT)) {
6311	Info.FFDiag(E, diag::note_constexpr_memcpy_type_pun) << Move << SrcT << T;
6312	return false;
6313	}
6314	if (T->isIncompleteType()) {
6315	Info.FFDiag(E, diag::note_constexpr_memcpy_incomplete_type) << Move << T;
6316	return false;
6317	}
6318	if (!T.isTriviallyCopyableType(Info.Ctx)) {
6319	Info.FFDiag(E, diag::note_constexpr_memcpy_nontrivial) << Move << T;
6320	return false;
6321	}
6322
6323	// Figure out how many T's we're copying.
6324	uint64_t TSize = Info.Ctx.getTypeSizeInChars(T).getQuantity();
6325	if (!WChar) {
6326	uint64_t Remainder;
6327	llvm::APInt OrigN = N;
6328	llvm::APInt::udivrem(OrigN, TSize, N, Remainder);
6329	if (Remainder) {
6330	Info.FFDiag(E, diag::note_constexpr_memcpy_unsupported)
6331	<< Move << WChar << 0 << T << OrigN.toString(10, /Signed/false)
6332	<< (unsigned)TSize;
6333	return false;
6334	}
6335	}
6336
6337	// Check that the copying will remain within the arrays, just so that we
6338	// can give a more meaningful diagnostic. This implicitly also checks that
6339	// N fits into 64 bits.
6340	uint64_t RemainingSrcSize = Src.Designator.validIndexAdjustments().second;
6341	uint64_t RemainingDestSize = Dest.Designator.validIndexAdjustments().second;
6342	if (N.ugt(RemainingSrcSize) \|\| N.ugt(RemainingDestSize)) {
6343	Info.FFDiag(E, diag::note_constexpr_memcpy_unsupported)
6344	<< Move << WChar << (N.ugt(RemainingSrcSize) ? 1 : 2) << T
6345	<< N.toString(10, /Signed/false);
6346	return false;
6347	}
6348	uint64_t NElems = N.getZExtValue();
6349	uint64_t NBytes = NElems * TSize;
6350
6351	// Check for overlap.
6352	int Direction = 1;
6353	if (HasSameBase(Src, Dest)) {
6354	uint64_t SrcOffset = Src.getLValueOffset().getQuantity();
6355	uint64_t DestOffset = Dest.getLValueOffset().getQuantity();
6356	if (DestOffset >= SrcOffset && DestOffset - SrcOffset < NBytes) {
6357	// Dest is inside the source region.
6358	if (!Move) {
6359	Info.FFDiag(E, diag::note_constexpr_memcpy_overlap) << WChar;
6360	return false;
6361	}
6362	// For memmove and friends, copy backwards.
6363	if (!HandleLValueArrayAdjustment(Info, E, Src, T, NElems - 1) \|\|
6364	!HandleLValueArrayAdjustment(Info, E, Dest, T, NElems - 1))
6365	return false;
6366	Direction = -1;
6367	} else if (!Move && SrcOffset >= DestOffset &&
6368	SrcOffset - DestOffset < NBytes) {
6369	// Src is inside the destination region for memcpy: invalid.
6370	Info.FFDiag(E, diag::note_constexpr_memcpy_overlap) << WChar;
6371	return false;
6372	}
6373	}
6374
6375	while (true) {
6376	APValue Val;
6377	if (!handleLValueToRValueConversion(Info, E, T, Src, Val) \|\|
6378	!handleAssignment(Info, E, Dest, T, Val))
6379	return false;
6380	// Do not iterate past the last element; if we're copying backwards, that
6381	// might take us off the start of the array.
6382	if (--NElems == 0)
6383	return true;
6384	if (!HandleLValueArrayAdjustment(Info, E, Src, T, Direction) \|\|
6385	!HandleLValueArrayAdjustment(Info, E, Dest, T, Direction))
6386	return false;
6387	}
6388	}
6389
6390	default:
6391	return visitNonBuiltinCallExpr(E);
6392	}
6393	}
6394
6395	//===----------------------------------------------------------------------===//
6396	// Member Pointer Evaluation
6397	//===----------------------------------------------------------------------===//
6398
6399	namespace {
6400	class MemberPointerExprEvaluator
6401	: public ExprEvaluatorBase<MemberPointerExprEvaluator> {
6402	MemberPtr &Result;
6403
6404	bool Success(const ValueDecl *D) {
6405	Result = MemberPtr(D);
6406	return true;
6407	}
6408	public:
6409
6410	MemberPointerExprEvaluator(EvalInfo &Info, MemberPtr &Result)
6411	: ExprEvaluatorBaseTy(Info), Result(Result) {}
6412
6413	bool Success(const APValue &V, const Expr *E) {
6414	Result.setFrom(V);
6415	return true;
6416	}
6417	bool ZeroInitialization(const Expr *E) {
6418	return Success((const ValueDecl*)nullptr);
6419	}
6420
6421	bool VisitCastExpr(const CastExpr *E);
6422	bool VisitUnaryAddrOf(const UnaryOperator *E);
6423	};
6424	} // end anonymous namespace
6425
6426	static bool EvaluateMemberPointer(const Expr *E, MemberPtr &Result,
6427	EvalInfo &Info) {
6428	isRValue() && E->getType()->isMemberPointerType()", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 6428, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(E->isRValue() && E->getType()->isMemberPointerType());
6429	return MemberPointerExprEvaluator(Info, Result).Visit(E);
6430	}
6431
6432	bool MemberPointerExprEvaluator::VisitCastExpr(const CastExpr *E) {
6433	switch (E->getCastKind()) {
6434	default:
6435	return ExprEvaluatorBaseTy::VisitCastExpr(E);
6436
6437	case CK_NullToMemberPointer:
6438	VisitIgnoredValue(E->getSubExpr());
6439	return ZeroInitialization(E);
6440
6441	case CK_BaseToDerivedMemberPointer: {
6442	if (!Visit(E->getSubExpr()))
6443	return false;
6444	if (E->path_empty())
6445	return true;
6446	// Base-to-derived member pointer casts store the path in derived-to-base
6447	// order, so iterate backwards. The CXXBaseSpecifier also provides us with
6448	// the wrong end of the derived->base arc, so stagger the path by one class.
6449	typedef std::reverse_iterator<CastExpr::path_const_iterator> ReverseIter;
6450	for (ReverseIter PathI(E->path_end() - 1), PathE(E->path_begin());
6451	PathI != PathE; ++PathI) {
6452	(0) . __assert_fail ("!(PathI)->isVirtual() && \"memptr cast through vbase\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 6452, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(!(PathI)->isVirtual() && "memptr cast through vbase");
6453	const CXXRecordDecl Derived = (PathI)->getType()->getAsCXXRecordDecl();
6454	if (!Result.castToDerived(Derived))
6455	return Error(E);
6456	}
6457	const Type *FinalTy = E->getType()->castAs<MemberPointerType>()->getClass();
6458	if (!Result.castToDerived(FinalTy->getAsCXXRecordDecl()))
6459	return Error(E);
6460	return true;
6461	}
6462
6463	case CK_DerivedToBaseMemberPointer:
6464	if (!Visit(E->getSubExpr()))
6465	return false;
6466	for (CastExpr::path_const_iterator PathI = E->path_begin(),
6467	PathE = E->path_end(); PathI != PathE; ++PathI) {
6468	(0) . __assert_fail ("!(PathI)->isVirtual() && \"memptr cast through vbase\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 6468, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(!(PathI)->isVirtual() && "memptr cast through vbase");
6469	const CXXRecordDecl Base = (PathI)->getType()->getAsCXXRecordDecl();
6470	if (!Result.castToBase(Base))
6471	return Error(E);
6472	}
6473	return true;
6474	}
6475	}
6476
6477	bool MemberPointerExprEvaluator::VisitUnaryAddrOf(const UnaryOperator *E) {
6478	// C++11 [expr.unary.op]p3 has very strict rules on how the address of a
6479	// member can be formed.
6480	return Success(cast<DeclRefExpr>(E->getSubExpr())->getDecl());
6481	}
6482
6483	//===----------------------------------------------------------------------===//
6484	// Record Evaluation
6485	//===----------------------------------------------------------------------===//
6486
6487	namespace {
6488	class RecordExprEvaluator
6489	: public ExprEvaluatorBase<RecordExprEvaluator> {
6490	const LValue &This;
6491	APValue &Result;
6492	public:
6493
6494	RecordExprEvaluator(EvalInfo &info, const LValue &This, APValue &Result)
6495	: ExprEvaluatorBaseTy(info), This(This), Result(Result) {}
6496
6497	bool Success(const APValue &V, const Expr *E) {
6498	Result = V;
6499	return true;
6500	}
6501	bool ZeroInitialization(const Expr *E) {
6502	return ZeroInitialization(E, E->getType());
6503	}
6504	bool ZeroInitialization(const Expr *E, QualType T);
6505
6506	bool VisitCallExpr(const CallExpr *E) {
6507	return handleCallExpr(E, Result, &This);
6508	}
6509	bool VisitCastExpr(const CastExpr *E);
6510	bool VisitInitListExpr(const InitListExpr *E);
6511	bool VisitCXXConstructExpr(const CXXConstructExpr *E) {
6512	return VisitCXXConstructExpr(E, E->getType());
6513	}
6514	bool VisitLambdaExpr(const LambdaExpr *E);
6515	bool VisitCXXInheritedCtorInitExpr(const CXXInheritedCtorInitExpr *E);
6516	bool VisitCXXConstructExpr(const CXXConstructExpr *E, QualType T);
6517	bool VisitCXXStdInitializerListExpr(const CXXStdInitializerListExpr *E);
6518
6519	bool VisitBinCmp(const BinaryOperator *E);
6520	};
6521	}
6522
6523	/// Perform zero-initialization on an object of non-union class type.
6524	/// C++11 [dcl.init]p5:
6525	/// To zero-initialize an object or reference of type T means:
6526	/// [...]
6527	/// -- if T is a (possibly cv-qualified) non-union class type,
6528	/// each non-static data member and each base-class subobject is
6529	/// zero-initialized
6530	static bool HandleClassZeroInitialization(EvalInfo &Info, const Expr *E,
6531	const RecordDecl *RD,
6532	const LValue &This, APValue &Result) {
6533	(0) . __assert_fail ("!RD->isUnion() && \"Expected non-union class type\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 6533, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(!RD->isUnion() && "Expected non-union class type");
6534	const CXXRecordDecl *CD = dyn_cast<CXXRecordDecl>(RD);
6535	Result = APValue(APValue::UninitStruct(), CD ? CD->getNumBases() : 0,
6536	std::distance(RD->field_begin(), RD->field_end()));
6537
6538	if (RD->isInvalidDecl()) return false;
6539	const ASTRecordLayout &Layout = Info.Ctx.getASTRecordLayout(RD);
6540
6541	if (CD) {
6542	unsigned Index = 0;
6543	for (CXXRecordDecl::base_class_const_iterator I = CD->bases_begin(),
6544	End = CD->bases_end(); I != End; ++I, ++Index) {
6545	const CXXRecordDecl *Base = I->getType()->getAsCXXRecordDecl();
6546	LValue Subobject = This;
6547	if (!HandleLValueDirectBase(Info, E, Subobject, CD, Base, &Layout))
6548	return false;
6549	if (!HandleClassZeroInitialization(Info, E, Base, Subobject,
6550	Result.getStructBase(Index)))
6551	return false;
6552	}
6553	}
6554
6555	for (const auto *I : RD->fields()) {
6556	// -- if T is a reference type, no initialization is performed.
6557	if (I->getType()->isReferenceType())
6558	continue;
6559
6560	LValue Subobject = This;
6561	if (!HandleLValueMember(Info, E, Subobject, I, &Layout))
6562	return false;
6563
6564	ImplicitValueInitExpr VIE(I->getType());
6565	if (!EvaluateInPlace(
6566	Result.getStructField(I->getFieldIndex()), Info, Subobject, &VIE))
6567	return false;
6568	}
6569
6570	return true;
6571	}
6572
6573	bool RecordExprEvaluator::ZeroInitialization(const Expr *E, QualType T) {
6574	const RecordDecl *RD = T->castAs<RecordType>()->getDecl();
6575	if (RD->isInvalidDecl()) return false;
6576	if (RD->isUnion()) {
6577	// C++11 [dcl.init]p5: If T is a (possibly cv-qualified) union type, the
6578	// object's first non-static named data member is zero-initialized
6579	RecordDecl::field_iterator I = RD->field_begin();
6580	if (I == RD->field_end()) {
6581	Result = APValue((const FieldDecl*)nullptr);
6582	return true;
6583	}
6584
6585	LValue Subobject = This;
6586	if (!HandleLValueMember(Info, E, Subobject, *I))
6587	return false;
6588	Result = APValue(*I);
6589	ImplicitValueInitExpr VIE(I->getType());
6590	return EvaluateInPlace(Result.getUnionValue(), Info, Subobject, &VIE);
6591	}
6592
6593	if (isa<CXXRecordDecl>(RD) && cast<CXXRecordDecl>(RD)->getNumVBases()) {
6594	Info.FFDiag(E, diag::note_constexpr_virtual_base) << RD;
6595	return false;
6596	}
6597
6598	return HandleClassZeroInitialization(Info, E, RD, This, Result);
6599	}
6600
6601	bool RecordExprEvaluator::VisitCastExpr(const CastExpr *E) {
6602	switch (E->getCastKind()) {
6603	default:
6604	return ExprEvaluatorBaseTy::VisitCastExpr(E);
6605
6606	case CK_ConstructorConversion:
6607	return Visit(E->getSubExpr());
6608
6609	case CK_DerivedToBase:
6610	case CK_UncheckedDerivedToBase: {
6611	APValue DerivedObject;
6612	if (!Evaluate(DerivedObject, Info, E->getSubExpr()))
6613	return false;
6614	if (!DerivedObject.isStruct())
6615	return Error(E->getSubExpr());
6616
6617	// Derived-to-base rvalue conversion: just slice off the derived part.
6618	APValue *Value = &DerivedObject;
6619	const CXXRecordDecl *RD = E->getSubExpr()->getType()->getAsCXXRecordDecl();
6620	for (CastExpr::path_const_iterator PathI = E->path_begin(),
6621	PathE = E->path_end(); PathI != PathE; ++PathI) {
6622	(0) . __assert_fail ("!(PathI)->isVirtual() && \"record rvalue with virtual base\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 6622, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(!(PathI)->isVirtual() && "record rvalue with virtual base");
6623	const CXXRecordDecl Base = (PathI)->getType()->getAsCXXRecordDecl();
6624	Value = &Value->getStructBase(getBaseIndex(RD, Base));
6625	RD = Base;
6626	}
6627	Result = *Value;
6628	return true;
6629	}
6630	}
6631	}
6632
6633	bool RecordExprEvaluator::VisitInitListExpr(const InitListExpr *E) {
6634	if (E->isTransparent())
6635	return Visit(E->getInit(0));
6636
6637	const RecordDecl *RD = E->getType()->castAs<RecordType>()->getDecl();
6638	if (RD->isInvalidDecl()) return false;
6639	const ASTRecordLayout &Layout = Info.Ctx.getASTRecordLayout(RD);
6640
6641	if (RD->isUnion()) {
6642	const FieldDecl *Field = E->getInitializedFieldInUnion();
6643	Result = APValue(Field);
6644	if (!Field)
6645	return true;
6646
6647	// If the initializer list for a union does not contain any elements, the
6648	// first element of the union is value-initialized.
6649	// FIXME: The element should be initialized from an initializer list.
6650	// Is this difference ever observable for initializer lists which
6651	// we don't build?
6652	ImplicitValueInitExpr VIE(Field->getType());
6653	const Expr *InitExpr = E->getNumInits() ? E->getInit(0) : &VIE;
6654
6655	LValue Subobject = This;
6656	if (!HandleLValueMember(Info, InitExpr, Subobject, Field, &Layout))
6657	return false;
6658
6659	// Temporarily override This, in case there's a CXXDefaultInitExpr in here.
6660	ThisOverrideRAII ThisOverride(*Info.CurrentCall, &This,
6661	isa<CXXDefaultInitExpr>(InitExpr));
6662
6663	return EvaluateInPlace(Result.getUnionValue(), Info, Subobject, InitExpr);
6664	}
6665
6666	auto *CXXRD = dyn_cast<CXXRecordDecl>(RD);
6667	if (Result.isUninit())
6668	Result = APValue(APValue::UninitStruct(), CXXRD ? CXXRD->getNumBases() : 0,
6669	std::distance(RD->field_begin(), RD->field_end()));
6670	unsigned ElementNo = 0;
6671	bool Success = true;
6672
6673	// Initialize base classes.
6674	if (CXXRD) {
6675	for (const auto &Base : CXXRD->bases()) {
6676	(0) . __assert_fail ("ElementNo < E->getNumInits() && \"missing init for base class\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 6676, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(ElementNo < E->getNumInits() && "missing init for base class");
6677	const Expr *Init = E->getInit(ElementNo);
6678
6679	LValue Subobject = This;
6680	if (!HandleLValueBase(Info, Init, Subobject, CXXRD, &Base))
6681	return false;
6682
6683	APValue &FieldVal = Result.getStructBase(ElementNo);
6684	if (!EvaluateInPlace(FieldVal, Info, Subobject, Init)) {
6685	if (!Info.noteFailure())
6686	return false;
6687	Success = false;
6688	}
6689	++ElementNo;
6690	}
6691	}
6692
6693	// Initialize members.
6694	for (const auto *Field : RD->fields()) {
6695	// Anonymous bit-fields are not considered members of the class for
6696	// purposes of aggregate initialization.
6697	if (Field->isUnnamedBitfield())
6698	continue;
6699
6700	LValue Subobject = This;
6701
6702	bool HaveInit = ElementNo < E->getNumInits();
6703
6704	// FIXME: Diagnostics here should point to the end of the initializer
6705	// list, not the start.
6706	if (!HandleLValueMember(Info, HaveInit ? E->getInit(ElementNo) : E,
6707	Subobject, Field, &Layout))
6708	return false;
6709
6710	// Perform an implicit value-initialization for members beyond the end of
6711	// the initializer list.
6712	ImplicitValueInitExpr VIE(HaveInit ? Info.Ctx.IntTy : Field->getType());
6713	const Expr *Init = HaveInit ? E->getInit(ElementNo++) : &VIE;
6714
6715	// Temporarily override This, in case there's a CXXDefaultInitExpr in here.
6716	ThisOverrideRAII ThisOverride(*Info.CurrentCall, &This,
6717	isa<CXXDefaultInitExpr>(Init));
6718
6719	APValue &FieldVal = Result.getStructField(Field->getFieldIndex());
6720	if (!EvaluateInPlace(FieldVal, Info, Subobject, Init) \|\|
6721	(Field->isBitField() && !truncateBitfieldValue(Info, Init,
6722	FieldVal, Field))) {
6723	if (!Info.noteFailure())
6724	return false;
6725	Success = false;
6726	}
6727	}
6728
6729	return Success;
6730	}
6731
6732	bool RecordExprEvaluator::VisitCXXConstructExpr(const CXXConstructExpr *E,
6733	QualType T) {
6734	// Note that E's type is not necessarily the type of our class here; we might
6735	// be initializing an array element instead.
6736	const CXXConstructorDecl *FD = E->getConstructor();
6737	if (FD->isInvalidDecl() \|\| FD->getParent()->isInvalidDecl()) return false;
6738
6739	bool ZeroInit = E->requiresZeroInitialization();
6740	if (CheckTrivialDefaultConstructor(Info, E->getExprLoc(), FD, ZeroInit)) {
6741	// If we've already performed zero-initialization, we're already done.
6742	if (!Result.isUninit())
6743	return true;
6744
6745	// We can get here in two different ways:
6746	// 1) We're performing value-initialization, and should zero-initialize
6747	// the object, or
6748	// 2) We're performing default-initialization of an object with a trivial
6749	// constexpr default constructor, in which case we should start the
6750	// lifetimes of all the base subobjects (there can be no data member
6751	// subobjects in this case) per [basic.life]p1.
6752	// Either way, ZeroInitialization is appropriate.
6753	return ZeroInitialization(E, T);
6754	}
6755
6756	const FunctionDecl *Definition = nullptr;
6757	auto Body = FD->getBody(Definition);
6758
6759	if (!CheckConstexprFunction(Info, E->getExprLoc(), FD, Definition, Body))
6760	return false;
6761
6762	// Avoid materializing a temporary for an elidable copy/move constructor.
6763	if (E->isElidable() && !ZeroInit)
6764	if (const MaterializeTemporaryExpr *ME
6765	= dyn_cast<MaterializeTemporaryExpr>(E->getArg(0)))
6766	return Visit(ME->GetTemporaryExpr());
6767
6768	if (ZeroInit && !ZeroInitialization(E, T))
6769	return false;
6770
6771	auto Args = llvm::makeArrayRef(E->getArgs(), E->getNumArgs());
6772	return HandleConstructorCall(E, This, Args,
6773	cast<CXXConstructorDecl>(Definition), Info,
6774	Result);
6775	}
6776
6777	bool RecordExprEvaluator::VisitCXXInheritedCtorInitExpr(
6778	const CXXInheritedCtorInitExpr *E) {
6779	if (!Info.CurrentCall) {
6780	assert(Info.checkingPotentialConstantExpression());
6781	return false;
6782	}
6783
6784	const CXXConstructorDecl *FD = E->getConstructor();
6785	if (FD->isInvalidDecl() \|\| FD->getParent()->isInvalidDecl())
6786	return false;
6787
6788	const FunctionDecl *Definition = nullptr;
6789	auto Body = FD->getBody(Definition);
6790
6791	if (!CheckConstexprFunction(Info, E->getExprLoc(), FD, Definition, Body))
6792	return false;
6793
6794	return HandleConstructorCall(E, This, Info.CurrentCall->Arguments,
6795	cast<CXXConstructorDecl>(Definition), Info,
6796	Result);
6797	}
6798
6799	bool RecordExprEvaluator::VisitCXXStdInitializerListExpr(
6800	const CXXStdInitializerListExpr *E) {
6801	const ConstantArrayType *ArrayType =
6802	Info.Ctx.getAsConstantArrayType(E->getSubExpr()->getType());
6803
6804	LValue Array;
6805	if (!EvaluateLValue(E->getSubExpr(), Array, Info))
6806	return false;
6807
6808	// Get a pointer to the first element of the array.
6809	Array.addArray(Info, E, ArrayType);
6810
6811	// FIXME: Perform the checks on the field types in SemaInit.
6812	RecordDecl *Record = E->getType()->castAs<RecordType>()->getDecl();
6813	RecordDecl::field_iterator Field = Record->field_begin();
6814	if (Field == Record->field_end())
6815	return Error(E);
6816
6817	// Start pointer.
6818	if (!Field->getType()->isPointerType() \|\|
6819	!Info.Ctx.hasSameType(Field->getType()->getPointeeType(),
6820	ArrayType->getElementType()))
6821	return Error(E);
6822
6823	// FIXME: What if the initializer_list type has base classes, etc?
6824	Result = APValue(APValue::UninitStruct(), 0, 2);
6825	Array.moveInto(Result.getStructField(0));
6826
6827	if (++Field == Record->field_end())
6828	return Error(E);
6829
6830	if (Field->getType()->isPointerType() &&
6831	Info.Ctx.hasSameType(Field->getType()->getPointeeType(),
6832	ArrayType->getElementType())) {
6833	// End pointer.
6834	if (!HandleLValueArrayAdjustment(Info, E, Array,
6835	ArrayType->getElementType(),
6836	ArrayType->getSize().getZExtValue()))
6837	return false;
6838	Array.moveInto(Result.getStructField(1));
6839	} else if (Info.Ctx.hasSameType(Field->getType(), Info.Ctx.getSizeType()))
6840	// Length.
6841	Result.getStructField(1) = APValue(APSInt(ArrayType->getSize()));
6842	else
6843	return Error(E);
6844
6845	if (++Field != Record->field_end())
6846	return Error(E);
6847
6848	return true;
6849	}
6850
6851	bool RecordExprEvaluator::VisitLambdaExpr(const LambdaExpr *E) {
6852	const CXXRecordDecl *ClosureClass = E->getLambdaClass();
6853	if (ClosureClass->isInvalidDecl()) return false;
6854
6855	if (Info.checkingPotentialConstantExpression()) return true;
6856
6857	const size_t NumFields =
6858	std::distance(ClosureClass->field_begin(), ClosureClass->field_end());
6859
6860	(0) . __assert_fail ("NumFields == (size_t)std..distance(E->capture_init_begin(), E->capture_init_end()) && \"The number of lambda capture initializers should equal the number of \" \"fields within the closure type\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 6863, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(NumFields == (size_t)std::distance(E->capture_init_begin(),
6861	(0) . __assert_fail ("NumFields == (size_t)std..distance(E->capture_init_begin(), E->capture_init_end()) && \"The number of lambda capture initializers should equal the number of \" \"fields within the closure type\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 6863, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true"> E->capture_init_end()) &&
6862	(0) . __assert_fail ("NumFields == (size_t)std..distance(E->capture_init_begin(), E->capture_init_end()) && \"The number of lambda capture initializers should equal the number of \" \"fields within the closure type\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 6863, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true"> "The number of lambda capture initializers should equal the number of "
6863	(0) . __assert_fail ("NumFields == (size_t)std..distance(E->capture_init_begin(), E->capture_init_end()) && \"The number of lambda capture initializers should equal the number of \" \"fields within the closure type\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 6863, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true"> "fields within the closure type");
6864
6865	Result = APValue(APValue::UninitStruct(), /NumBases/0, NumFields);
6866	// Iterate through all the lambda's closure object's fields and initialize
6867	// them.
6868	auto *CaptureInitIt = E->capture_init_begin();
6869	const LambdaCapture *CaptureIt = ClosureClass->captures_begin();
6870	bool Success = true;
6871	for (const auto *Field : ClosureClass->fields()) {
6872	capture_init_end()", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 6872, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(CaptureInitIt != E->capture_init_end());
6873	// Get the initializer for this field
6874	Expr const CurFieldInit = CaptureInitIt++;
6875
6876	// If there is no initializer, either this is a VLA or an error has
6877	// occurred.
6878	if (!CurFieldInit)
6879	return Error(E);
6880
6881	APValue &FieldVal = Result.getStructField(Field->getFieldIndex());
6882	if (!EvaluateInPlace(FieldVal, Info, This, CurFieldInit)) {
6883	if (!Info.keepEvaluatingAfterFailure())
6884	return false;
6885	Success = false;
6886	}
6887	++CaptureIt;
6888	}
6889	return Success;
6890	}
6891
6892	static bool EvaluateRecord(const Expr *E, const LValue &This,
6893	APValue &Result, EvalInfo &Info) {
6894	(0) . __assert_fail ("E->isRValue() && E->getType()->isRecordType() && \"can't evaluate expression as a record rvalue\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 6895, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(E->isRValue() && E->getType()->isRecordType() &&
6895	(0) . __assert_fail ("E->isRValue() && E->getType()->isRecordType() && \"can't evaluate expression as a record rvalue\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 6895, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true"> "can't evaluate expression as a record rvalue");
6896	return RecordExprEvaluator(Info, This, Result).Visit(E);
6897	}
6898
6899	//===----------------------------------------------------------------------===//
6900	// Temporary Evaluation
6901	//
6902	// Temporaries are represented in the AST as rvalues, but generally behave like
6903	// lvalues. The full-object of which the temporary is a subobject is implicitly
6904	// materialized so that a reference can bind to it.
6905	//===----------------------------------------------------------------------===//
6906	namespace {
6907	class TemporaryExprEvaluator
6908	: public LValueExprEvaluatorBase<TemporaryExprEvaluator> {
6909	public:
6910	TemporaryExprEvaluator(EvalInfo &Info, LValue &Result) :
6911	LValueExprEvaluatorBaseTy(Info, Result, false) {}
6912
6913	/// Visit an expression which constructs the value of this temporary.
6914	bool VisitConstructExpr(const Expr *E) {
6915	APValue &Value = createTemporary(E, false, Result, *Info.CurrentCall);
6916	return EvaluateInPlace(Value, Info, Result, E);
6917	}
6918
6919	bool VisitCastExpr(const CastExpr *E) {
6920	switch (E->getCastKind()) {
6921	default:
6922	return LValueExprEvaluatorBaseTy::VisitCastExpr(E);
6923
6924	case CK_ConstructorConversion:
6925	return VisitConstructExpr(E->getSubExpr());
6926	}
6927	}
6928	bool VisitInitListExpr(const InitListExpr *E) {
6929	return VisitConstructExpr(E);
6930	}
6931	bool VisitCXXConstructExpr(const CXXConstructExpr *E) {
6932	return VisitConstructExpr(E);
6933	}
6934	bool VisitCallExpr(const CallExpr *E) {
6935	return VisitConstructExpr(E);
6936	}
6937	bool VisitCXXStdInitializerListExpr(const CXXStdInitializerListExpr *E) {
6938	return VisitConstructExpr(E);
6939	}
6940	bool VisitLambdaExpr(const LambdaExpr *E) {
6941	return VisitConstructExpr(E);
6942	}
6943	};
6944	} // end anonymous namespace
6945
6946	/// Evaluate an expression of record type as a temporary.
6947	static bool EvaluateTemporary(const Expr *E, LValue &Result, EvalInfo &Info) {
6948	isRValue() && E->getType()->isRecordType()", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 6948, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(E->isRValue() && E->getType()->isRecordType());
6949	return TemporaryExprEvaluator(Info, Result).Visit(E);
6950	}
6951
6952	//===----------------------------------------------------------------------===//
6953	// Vector Evaluation
6954	//===----------------------------------------------------------------------===//
6955
6956	namespace {
6957	class VectorExprEvaluator
6958	: public ExprEvaluatorBase<VectorExprEvaluator> {
6959	APValue &Result;
6960	public:
6961
6962	VectorExprEvaluator(EvalInfo &info, APValue &Result)
6963	: ExprEvaluatorBaseTy(info), Result(Result) {}
6964
6965	bool Success(ArrayRef<APValue> V, const Expr *E) {
6966	getType()->castAs()->getNumElements()", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 6966, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(V.size() == E->getType()->castAs<VectorType>()->getNumElements());
6967	// FIXME: remove this APValue copy.
6968	Result = APValue(V.data(), V.size());
6969	return true;
6970	}
6971	bool Success(const APValue &V, const Expr *E) {
6972	assert(V.isVector());
6973	Result = V;
6974	return true;
6975	}
6976	bool ZeroInitialization(const Expr *E);
6977
6978	bool VisitUnaryReal(const UnaryOperator *E)
6979	{ return Visit(E->getSubExpr()); }
6980	bool VisitCastExpr(const CastExpr* E);
6981	bool VisitInitListExpr(const InitListExpr *E);
6982	bool VisitUnaryImag(const UnaryOperator *E);
6983	// FIXME: Missing: unary -, unary ~, binary add/sub/mul/div,
6984	// binary comparisons, binary and/or/xor,
6985	// shufflevector, ExtVectorElementExpr
6986	};
6987	} // end anonymous namespace
6988
6989	static bool EvaluateVector(const Expr* E, APValue& Result, EvalInfo &Info) {
6990	(0) . __assert_fail ("E->isRValue() && E->getType()->isVectorType() &&\"not a vector rvalue\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 6990, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(E->isRValue() && E->getType()->isVectorType() &&"not a vector rvalue");
6991	return VectorExprEvaluator(Info, Result).Visit(E);
6992	}
6993
6994	bool VectorExprEvaluator::VisitCastExpr(const CastExpr *E) {
6995	const VectorType *VTy = E->getType()->castAs<VectorType>();
6996	unsigned NElts = VTy->getNumElements();
6997
6998	const Expr *SE = E->getSubExpr();
6999	QualType SETy = SE->getType();
7000
7001	switch (E->getCastKind()) {
7002	case CK_VectorSplat: {
7003	APValue Val = APValue();
7004	if (SETy->isIntegerType()) {
7005	APSInt IntResult;
7006	if (!EvaluateInteger(SE, IntResult, Info))
7007	return false;
7008	Val = APValue(std::move(IntResult));
7009	} else if (SETy->isRealFloatingType()) {
7010	APFloat FloatResult(0.0);
7011	if (!EvaluateFloat(SE, FloatResult, Info))
7012	return false;
7013	Val = APValue(std::move(FloatResult));
7014	} else {
7015	return Error(E);
7016	}
7017
7018	// Splat and create vector APValue.
7019	SmallVector<APValue, 4> Elts(NElts, Val);
7020	return Success(Elts, E);
7021	}
7022	case CK_BitCast: {
7023	// Evaluate the operand into an APInt we can extract from.
7024	llvm::APInt SValInt;
7025	if (!EvalAndBitcastToAPInt(Info, SE, SValInt))
7026	return false;
7027	// Extract the elements
7028	QualType EltTy = VTy->getElementType();
7029	unsigned EltSize = Info.Ctx.getTypeSize(EltTy);
7030	bool BigEndian = Info.Ctx.getTargetInfo().isBigEndian();
7031	SmallVector<APValue, 4> Elts;
7032	if (EltTy->isRealFloatingType()) {
7033	const llvm::fltSemantics &Sem = Info.Ctx.getFloatTypeSemantics(EltTy);
7034	unsigned FloatEltSize = EltSize;
7035	if (&Sem == &APFloat::x87DoubleExtended())
7036	FloatEltSize = 80;
7037	for (unsigned i = 0; i < NElts; i++) {
7038	llvm::APInt Elt;
7039	if (BigEndian)
7040	Elt = SValInt.rotl(i*EltSize+FloatEltSize).trunc(FloatEltSize);
7041	else
7042	Elt = SValInt.rotr(i*EltSize).trunc(FloatEltSize);
7043	Elts.push_back(APValue(APFloat(Sem, Elt)));
7044	}
7045	} else if (EltTy->isIntegerType()) {
7046	for (unsigned i = 0; i < NElts; i++) {
7047	llvm::APInt Elt;
7048	if (BigEndian)
7049	Elt = SValInt.rotl(i*EltSize+EltSize).zextOrTrunc(EltSize);
7050	else
7051	Elt = SValInt.rotr(i*EltSize).zextOrTrunc(EltSize);
7052	Elts.push_back(APValue(APSInt(Elt, EltTy->isSignedIntegerType())));
7053	}
7054	} else {
7055	return Error(E);
7056	}
7057	return Success(Elts, E);
7058	}
7059	default:
7060	return ExprEvaluatorBaseTy::VisitCastExpr(E);
7061	}
7062	}
7063
7064	bool
7065	VectorExprEvaluator::VisitInitListExpr(const InitListExpr *E) {
7066	const VectorType *VT = E->getType()->castAs<VectorType>();
7067	unsigned NumInits = E->getNumInits();
7068	unsigned NumElements = VT->getNumElements();
7069
7070	QualType EltTy = VT->getElementType();
7071	SmallVector<APValue, 4> Elements;
7072
7073	// The number of initializers can be less than the number of
7074	// vector elements. For OpenCL, this can be due to nested vector
7075	// initialization. For GCC compatibility, missing trailing elements
7076	// should be initialized with zeroes.
7077	unsigned CountInits = 0, CountElts = 0;
7078	while (CountElts < NumElements) {
7079	// Handle nested vector initialization.
7080	if (CountInits < NumInits
7081	&& E->getInit(CountInits)->getType()->isVectorType()) {
7082	APValue v;
7083	if (!EvaluateVector(E->getInit(CountInits), v, Info))
7084	return Error(E);
7085	unsigned vlen = v.getVectorLength();
7086	for (unsigned j = 0; j < vlen; j++)
7087	Elements.push_back(v.getVectorElt(j));
7088	CountElts += vlen;
7089	} else if (EltTy->isIntegerType()) {
7090	llvm::APSInt sInt(32);
7091	if (CountInits < NumInits) {
7092	if (!EvaluateInteger(E->getInit(CountInits), sInt, Info))
7093	return false;
7094	} else // trailing integer zero.
7095	sInt = Info.Ctx.MakeIntValue(0, EltTy);
7096	Elements.push_back(APValue(sInt));
7097	CountElts++;
7098	} else {
7099	llvm::APFloat f(0.0);
7100	if (CountInits < NumInits) {
7101	if (!EvaluateFloat(E->getInit(CountInits), f, Info))
7102	return false;
7103	} else // trailing float zero.
7104	f = APFloat::getZero(Info.Ctx.getFloatTypeSemantics(EltTy));
7105	Elements.push_back(APValue(f));
7106	CountElts++;
7107	}
7108	CountInits++;
7109	}
7110	return Success(Elements, E);
7111	}
7112
7113	bool
7114	VectorExprEvaluator::ZeroInitialization(const Expr *E) {
7115	const VectorType *VT = E->getType()->getAs<VectorType>();
7116	QualType EltTy = VT->getElementType();
7117	APValue ZeroElement;
7118	if (EltTy->isIntegerType())
7119	ZeroElement = APValue(Info.Ctx.MakeIntValue(0, EltTy));
7120	else
7121	ZeroElement =
7122	APValue(APFloat::getZero(Info.Ctx.getFloatTypeSemantics(EltTy)));
7123
7124	SmallVector<APValue, 4> Elements(VT->getNumElements(), ZeroElement);
7125	return Success(Elements, E);
7126	}
7127
7128	bool VectorExprEvaluator::VisitUnaryImag(const UnaryOperator *E) {
7129	VisitIgnoredValue(E->getSubExpr());
7130	return ZeroInitialization(E);
7131	}
7132
7133	//===----------------------------------------------------------------------===//
7134	// Array Evaluation
7135	//===----------------------------------------------------------------------===//
7136
7137	namespace {
7138	class ArrayExprEvaluator
7139	: public ExprEvaluatorBase<ArrayExprEvaluator> {
7140	const LValue &This;
7141	APValue &Result;
7142	public:
7143
7144	ArrayExprEvaluator(EvalInfo &Info, const LValue &This, APValue &Result)
7145	: ExprEvaluatorBaseTy(Info), This(This), Result(Result) {}
7146
7147	bool Success(const APValue &V, const Expr *E) {
7148	(0) . __assert_fail ("V.isArray() && \"expected array\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 7148, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(V.isArray() && "expected array");
7149	Result = V;
7150	return true;
7151	}
7152
7153	bool ZeroInitialization(const Expr *E) {
7154	const ConstantArrayType *CAT =
7155	Info.Ctx.getAsConstantArrayType(E->getType());
7156	if (!CAT)
7157	return Error(E);
7158
7159	Result = APValue(APValue::UninitArray(), 0,
7160	CAT->getSize().getZExtValue());
7161	if (!Result.hasArrayFiller()) return true;
7162
7163	// Zero-initialize all elements.
7164	LValue Subobject = This;
7165	Subobject.addArray(Info, E, CAT);
7166	ImplicitValueInitExpr VIE(CAT->getElementType());
7167	return EvaluateInPlace(Result.getArrayFiller(), Info, Subobject, &VIE);
7168	}
7169
7170	bool VisitCallExpr(const CallExpr *E) {
7171	return handleCallExpr(E, Result, &This);
7172	}
7173	bool VisitInitListExpr(const InitListExpr *E);
7174	bool VisitArrayInitLoopExpr(const ArrayInitLoopExpr *E);
7175	bool VisitCXXConstructExpr(const CXXConstructExpr *E);
7176	bool VisitCXXConstructExpr(const CXXConstructExpr *E,
7177	const LValue &Subobject,
7178	APValue *Value, QualType Type);
7179	bool VisitStringLiteral(const StringLiteral *E) {
7180	expandStringLiteral(Info, E, Result);
7181	return true;
7182	}
7183	};
7184	} // end anonymous namespace
7185
7186	static bool EvaluateArray(const Expr *E, const LValue &This,
7187	APValue &Result, EvalInfo &Info) {
7188	(0) . __assert_fail ("E->isRValue() && E->getType()->isArrayType() && \"not an array rvalue\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 7188, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(E->isRValue() && E->getType()->isArrayType() && "not an array rvalue");
7189	return ArrayExprEvaluator(Info, This, Result).Visit(E);
7190	}
7191
7192	// Return true iff the given array filler may depend on the element index.
7193	static bool MaybeElementDependentArrayFiller(const Expr *FillerExpr) {
7194	// For now, just whitelist non-class value-initialization and initialization
7195	// lists comprised of them.
7196	if (isa<ImplicitValueInitExpr>(FillerExpr))
7197	return false;
7198	if (const InitListExpr *ILE = dyn_cast<InitListExpr>(FillerExpr)) {
7199	for (unsigned I = 0, E = ILE->getNumInits(); I != E; ++I) {
7200	if (MaybeElementDependentArrayFiller(ILE->getInit(I)))
7201	return true;
7202	}
7203	return false;
7204	}
7205	return true;
7206	}
7207
7208	bool ArrayExprEvaluator::VisitInitListExpr(const InitListExpr *E) {
7209	const ConstantArrayType *CAT = Info.Ctx.getAsConstantArrayType(E->getType());
7210	if (!CAT)
7211	return Error(E);
7212
7213	// C++11 [dcl.init.string]p1: A char array [...] can be initialized by [...]
7214	// an appropriately-typed string literal enclosed in braces.
7215	if (E->isStringLiteralInit())
7216	return Visit(E->getInit(0));
7217
7218	bool Success = true;
7219
7220	(0) . __assert_fail ("(!Result.isArray() \|\| Result.getArrayInitializedElts() == 0) && \"zero-initialized array shouldn't have any initialized elts\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 7221, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert((!Result.isArray() \|\| Result.getArrayInitializedElts() == 0) &&
7221	(0) . __assert_fail ("(!Result.isArray() \|\| Result.getArrayInitializedElts() == 0) && \"zero-initialized array shouldn't have any initialized elts\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 7221, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true"> "zero-initialized array shouldn't have any initialized elts");
7222	APValue Filler;
7223	if (Result.isArray() && Result.hasArrayFiller())
7224	Filler = Result.getArrayFiller();
7225
7226	unsigned NumEltsToInit = E->getNumInits();
7227	unsigned NumElts = CAT->getSize().getZExtValue();
7228	const Expr *FillerExpr = E->hasArrayFiller() ? E->getArrayFiller() : nullptr;
7229
7230	// If the initializer might depend on the array index, run it for each
7231	// array element.
7232	if (NumEltsToInit != NumElts && MaybeElementDependentArrayFiller(FillerExpr))
7233	NumEltsToInit = NumElts;
7234
7235	LLVM_DEBUG(llvm::dbgs() << "The number of elements to initialize: "
7236	<< NumEltsToInit << ".\n");
7237
7238	Result = APValue(APValue::UninitArray(), NumEltsToInit, NumElts);
7239
7240	// If the array was previously zero-initialized, preserve the
7241	// zero-initialized values.
7242	if (!Filler.isUninit()) {
7243	for (unsigned I = 0, E = Result.getArrayInitializedElts(); I != E; ++I)
7244	Result.getArrayInitializedElt(I) = Filler;
7245	if (Result.hasArrayFiller())
7246	Result.getArrayFiller() = Filler;
7247	}
7248
7249	LValue Subobject = This;
7250	Subobject.addArray(Info, E, CAT);
7251	for (unsigned Index = 0; Index != NumEltsToInit; ++Index) {
7252	const Expr *Init =
7253	Index < E->getNumInits() ? E->getInit(Index) : FillerExpr;
7254	if (!EvaluateInPlace(Result.getArrayInitializedElt(Index),
7255	Info, Subobject, Init) \|\|
7256	!HandleLValueArrayAdjustment(Info, Init, Subobject,
7257	CAT->getElementType(), 1)) {
7258	if (!Info.noteFailure())
7259	return false;
7260	Success = false;
7261	}
7262	}
7263
7264	if (!Result.hasArrayFiller())
7265	return Success;
7266
7267	// If we get here, we have a trivial filler, which we can just evaluate
7268	// once and splat over the rest of the array elements.
7269	(0) . __assert_fail ("FillerExpr && \"no array filler for incomplete init list\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 7269, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(FillerExpr && "no array filler for incomplete init list");
7270	return EvaluateInPlace(Result.getArrayFiller(), Info, Subobject,
7271	FillerExpr) && Success;
7272	}
7273
7274	bool ArrayExprEvaluator::VisitArrayInitLoopExpr(const ArrayInitLoopExpr *E) {
7275	if (E->getCommonExpr() &&
7276	!Evaluate(Info.CurrentCall->createTemporary(E->getCommonExpr(), false),
7277	Info, E->getCommonExpr()->getSourceExpr()))
7278	return false;
7279
7280	auto *CAT = cast<ConstantArrayType>(E->getType()->castAsArrayTypeUnsafe());
7281
7282	uint64_t Elements = CAT->getSize().getZExtValue();
7283	Result = APValue(APValue::UninitArray(), Elements, Elements);
7284
7285	LValue Subobject = This;
7286	Subobject.addArray(Info, E, CAT);
7287
7288	bool Success = true;
7289	for (EvalInfo::ArrayInitLoopIndex Index(Info); Index != Elements; ++Index) {
7290	if (!EvaluateInPlace(Result.getArrayInitializedElt(Index),
7291	Info, Subobject, E->getSubExpr()) \|\|
7292	!HandleLValueArrayAdjustment(Info, E, Subobject,
7293	CAT->getElementType(), 1)) {
7294	if (!Info.noteFailure())
7295	return false;
7296	Success = false;
7297	}
7298	}
7299
7300	return Success;
7301	}
7302
7303	bool ArrayExprEvaluator::VisitCXXConstructExpr(const CXXConstructExpr *E) {
7304	return VisitCXXConstructExpr(E, This, &Result, E->getType());
7305	}
7306
7307	bool ArrayExprEvaluator::VisitCXXConstructExpr(const CXXConstructExpr *E,
7308	const LValue &Subobject,
7309	APValue *Value,
7310	QualType Type) {
7311	bool HadZeroInit = !Value->isUninit();
7312
7313	if (const ConstantArrayType *CAT = Info.Ctx.getAsConstantArrayType(Type)) {
7314	unsigned N = CAT->getSize().getZExtValue();
7315
7316	// Preserve the array filler if we had prior zero-initialization.
7317	APValue Filler =
7318	HadZeroInit && Value->hasArrayFiller() ? Value->getArrayFiller()
7319	: APValue();
7320
7321	*Value = APValue(APValue::UninitArray(), N, N);
7322
7323	if (HadZeroInit)
7324	for (unsigned I = 0; I != N; ++I)
7325	Value->getArrayInitializedElt(I) = Filler;
7326
7327	// Initialize the elements.
7328	LValue ArrayElt = Subobject;
7329	ArrayElt.addArray(Info, E, CAT);
7330	for (unsigned I = 0; I != N; ++I)
7331	if (!VisitCXXConstructExpr(E, ArrayElt, &Value->getArrayInitializedElt(I),
7332	CAT->getElementType()) \|\|
7333	!HandleLValueArrayAdjustment(Info, E, ArrayElt,
7334	CAT->getElementType(), 1))
7335	return false;
7336
7337	return true;
7338	}
7339
7340	if (!Type->isRecordType())
7341	return Error(E);
7342
7343	return RecordExprEvaluator(Info, Subobject, *Value)
7344	.VisitCXXConstructExpr(E, Type);
7345	}
7346
7347	//===----------------------------------------------------------------------===//
7348	// Integer Evaluation
7349	//
7350	// As a GNU extension, we support casting pointers to sufficiently-wide integer
7351	// types and back in constant folding. Integer values are thus represented
7352	// either as an integer-valued APValue, or as an lvalue-valued APValue.
7353	//===----------------------------------------------------------------------===//
7354
7355	namespace {
7356	class IntExprEvaluator
7357	: public ExprEvaluatorBase<IntExprEvaluator> {
7358	APValue &Result;
7359	public:
7360	IntExprEvaluator(EvalInfo &info, APValue &result)
7361	: ExprEvaluatorBaseTy(info), Result(result) {}
7362
7363	bool Success(const llvm::APSInt &SI, const Expr *E, APValue &Result) {
7364	(0) . __assert_fail ("E->getType()->isIntegralOrEnumerationType() && \"Invalid evaluation result.\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 7365, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(E->getType()->isIntegralOrEnumerationType() &&
7365	(0) . __assert_fail ("E->getType()->isIntegralOrEnumerationType() && \"Invalid evaluation result.\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 7365, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true"> "Invalid evaluation result.");
7366	(0) . __assert_fail ("SI.isSigned() == E->getType()->isSignedIntegerOrEnumerationType() && \"Invalid evaluation result.\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 7367, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(SI.isSigned() == E->getType()->isSignedIntegerOrEnumerationType() &&
7367	(0) . __assert_fail ("SI.isSigned() == E->getType()->isSignedIntegerOrEnumerationType() && \"Invalid evaluation result.\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 7367, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true"> "Invalid evaluation result.");
7368	(0) . __assert_fail ("SI.getBitWidth() == Info.Ctx.getIntWidth(E->getType()) && \"Invalid evaluation result.\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 7369, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(SI.getBitWidth() == Info.Ctx.getIntWidth(E->getType()) &&
7369	(0) . __assert_fail ("SI.getBitWidth() == Info.Ctx.getIntWidth(E->getType()) && \"Invalid evaluation result.\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 7369, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true"> "Invalid evaluation result.");
7370	Result = APValue(SI);
7371	return true;
7372	}
7373	bool Success(const llvm::APSInt &SI, const Expr *E) {
7374	return Success(SI, E, Result);
7375	}
7376
7377	bool Success(const llvm::APInt &I, const Expr *E, APValue &Result) {
7378	(0) . __assert_fail ("E->getType()->isIntegralOrEnumerationType() && \"Invalid evaluation result.\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 7379, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(E->getType()->isIntegralOrEnumerationType() &&
7379	(0) . __assert_fail ("E->getType()->isIntegralOrEnumerationType() && \"Invalid evaluation result.\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 7379, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true"> "Invalid evaluation result.");
7380	(0) . __assert_fail ("I.getBitWidth() == Info.Ctx.getIntWidth(E->getType()) && \"Invalid evaluation result.\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 7381, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(I.getBitWidth() == Info.Ctx.getIntWidth(E->getType()) &&
7381	(0) . __assert_fail ("I.getBitWidth() == Info.Ctx.getIntWidth(E->getType()) && \"Invalid evaluation result.\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 7381, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true"> "Invalid evaluation result.");
7382	Result = APValue(APSInt(I));
7383	Result.getInt().setIsUnsigned(
7384	E->getType()->isUnsignedIntegerOrEnumerationType());
7385	return true;
7386	}
7387	bool Success(const llvm::APInt &I, const Expr *E) {
7388	return Success(I, E, Result);
7389	}
7390
7391	bool Success(uint64_t Value, const Expr *E, APValue &Result) {
7392	(0) . __assert_fail ("E->getType()->isIntegralOrEnumerationType() && \"Invalid evaluation result.\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 7393, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(E->getType()->isIntegralOrEnumerationType() &&
7393	(0) . __assert_fail ("E->getType()->isIntegralOrEnumerationType() && \"Invalid evaluation result.\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 7393, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true"> "Invalid evaluation result.");
7394	Result = APValue(Info.Ctx.MakeIntValue(Value, E->getType()));
7395	return true;
7396	}
7397	bool Success(uint64_t Value, const Expr *E) {
7398	return Success(Value, E, Result);
7399	}
7400
7401	bool Success(CharUnits Size, const Expr *E) {
7402	return Success(Size.getQuantity(), E);
7403	}
7404
7405	bool Success(const APValue &V, const Expr *E) {
7406	if (V.isLValue() \|\| V.isAddrLabelDiff()) {
7407	Result = V;
7408	return true;
7409	}
7410	return Success(V.getInt(), E);
7411	}
7412
7413	bool ZeroInitialization(const Expr *E) { return Success(0, E); }
7414
7415	//===--------------------------------------------------------------------===//
7416	// Visitor Methods
7417	//===--------------------------------------------------------------------===//
7418
7419	bool VisitConstantExpr(const ConstantExpr *E);
7420
7421	bool VisitIntegerLiteral(const IntegerLiteral *E) {
7422	return Success(E->getValue(), E);
7423	}
7424	bool VisitCharacterLiteral(const CharacterLiteral *E) {
7425	return Success(E->getValue(), E);
7426	}
7427
7428	bool CheckReferencedDecl(const Expr E, const Decl D);
7429	bool VisitDeclRefExpr(const DeclRefExpr *E) {
7430	if (CheckReferencedDecl(E, E->getDecl()))
7431	return true;
7432
7433	return ExprEvaluatorBaseTy::VisitDeclRefExpr(E);
7434	}
7435	bool VisitMemberExpr(const MemberExpr *E) {
7436	if (CheckReferencedDecl(E, E->getMemberDecl())) {
7437	VisitIgnoredBaseExpression(E->getBase());
7438	return true;
7439	}
7440
7441	return ExprEvaluatorBaseTy::VisitMemberExpr(E);
7442	}
7443
7444	bool VisitCallExpr(const CallExpr *E);
7445	bool VisitBuiltinCallExpr(const CallExpr *E, unsigned BuiltinOp);
7446	bool VisitBinaryOperator(const BinaryOperator *E);
7447	bool VisitOffsetOfExpr(const OffsetOfExpr *E);
7448	bool VisitUnaryOperator(const UnaryOperator *E);
7449
7450	bool VisitCastExpr(const CastExpr* E);
7451	bool VisitUnaryExprOrTypeTraitExpr(const UnaryExprOrTypeTraitExpr *E);
7452
7453	bool VisitCXXBoolLiteralExpr(const CXXBoolLiteralExpr *E) {
7454	return Success(E->getValue(), E);
7455	}
7456
7457	bool VisitObjCBoolLiteralExpr(const ObjCBoolLiteralExpr *E) {
7458	return Success(E->getValue(), E);
7459	}
7460
7461	bool VisitArrayInitIndexExpr(const ArrayInitIndexExpr *E) {
7462	if (Info.ArrayInitIndex == uint64_t(-1)) {
7463	// We were asked to evaluate this subexpression independent of the
7464	// enclosing ArrayInitLoopExpr. We can't do that.
7465	Info.FFDiag(E);
7466	return false;
7467	}
7468	return Success(Info.ArrayInitIndex, E);
7469	}
7470
7471	// Note, GNU defines __null as an integer, not a pointer.
7472	bool VisitGNUNullExpr(const GNUNullExpr *E) {
7473	return ZeroInitialization(E);
7474	}
7475
7476	bool VisitTypeTraitExpr(const TypeTraitExpr *E) {
7477	return Success(E->getValue(), E);
7478	}
7479
7480	bool VisitArrayTypeTraitExpr(const ArrayTypeTraitExpr *E) {
7481	return Success(E->getValue(), E);
7482	}
7483
7484	bool VisitExpressionTraitExpr(const ExpressionTraitExpr *E) {
7485	return Success(E->getValue(), E);
7486	}
7487
7488	bool VisitUnaryReal(const UnaryOperator *E);
7489	bool VisitUnaryImag(const UnaryOperator *E);
7490
7491	bool VisitCXXNoexceptExpr(const CXXNoexceptExpr *E);
7492	bool VisitSizeOfPackExpr(const SizeOfPackExpr *E);
7493
7494	// FIXME: Missing: array subscript of vector, member of vector
7495	};
7496
7497	class FixedPointExprEvaluator
7498	: public ExprEvaluatorBase<FixedPointExprEvaluator> {
7499	APValue &Result;
7500
7501	public:
7502	FixedPointExprEvaluator(EvalInfo &info, APValue &result)
7503	: ExprEvaluatorBaseTy(info), Result(result) {}
7504
7505	bool Success(const llvm::APInt &I, const Expr *E) {
7506	return Success(
7507	APFixedPoint(I, Info.Ctx.getFixedPointSemantics(E->getType())), E);
7508	}
7509
7510	bool Success(uint64_t Value, const Expr *E) {
7511	return Success(
7512	APFixedPoint(Value, Info.Ctx.getFixedPointSemantics(E->getType())), E);
7513	}
7514
7515	bool Success(const APValue &V, const Expr *E) {
7516	return Success(V.getFixedPoint(), E);
7517	}
7518
7519	bool Success(const APFixedPoint &V, const Expr *E) {
7520	(0) . __assert_fail ("E->getType()->isFixedPointType() && \"Invalid evaluation result.\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 7520, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(E->getType()->isFixedPointType() && "Invalid evaluation result.");
7521	(0) . __assert_fail ("V.getWidth() == Info.Ctx.getIntWidth(E->getType()) && \"Invalid evaluation result.\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 7522, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(V.getWidth() == Info.Ctx.getIntWidth(E->getType()) &&
7522	(0) . __assert_fail ("V.getWidth() == Info.Ctx.getIntWidth(E->getType()) && \"Invalid evaluation result.\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 7522, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true"> "Invalid evaluation result.");
7523	Result = APValue(V);
7524	return true;
7525	}
7526
7527	//===--------------------------------------------------------------------===//
7528	// Visitor Methods
7529	//===--------------------------------------------------------------------===//
7530
7531	bool VisitFixedPointLiteral(const FixedPointLiteral *E) {
7532	return Success(E->getValue(), E);
7533	}
7534
7535	bool VisitCastExpr(const CastExpr *E);
7536	bool VisitUnaryOperator(const UnaryOperator *E);
7537	bool VisitBinaryOperator(const BinaryOperator *E);
7538	};
7539	} // end anonymous namespace
7540
7541	/// EvaluateIntegerOrLValue - Evaluate an rvalue integral-typed expression, and
7542	/// produce either the integer value or a pointer.
7543	///
7544	/// GCC has a heinous extension which folds casts between pointer types and
7545	/// pointer-sized integral types. We support this by allowing the evaluation of
7546	/// an integer rvalue to produce a pointer (represented as an lvalue) instead.
7547	/// Some simple arithmetic on such values is supported (they are treated much
7548	/// like char*).
7549	static bool EvaluateIntegerOrLValue(const Expr *E, APValue &Result,
7550	EvalInfo &Info) {
7551	isRValue() && E->getType()->isIntegralOrEnumerationType()", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 7551, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(E->isRValue() && E->getType()->isIntegralOrEnumerationType());
7552	return IntExprEvaluator(Info, Result).Visit(E);
7553	}
7554
7555	static bool EvaluateInteger(const Expr *E, APSInt &Result, EvalInfo &Info) {
7556	APValue Val;
7557	if (!EvaluateIntegerOrLValue(E, Val, Info))
7558	return false;
7559	if (!Val.isInt()) {
7560	// FIXME: It would be better to produce the diagnostic for casting
7561	// a pointer to an integer.
7562	Info.FFDiag(E, diag::note_invalid_subexpr_in_const_expr);
7563	return false;
7564	}
7565	Result = Val.getInt();
7566	return true;
7567	}
7568
7569	static bool EvaluateFixedPoint(const Expr *E, APFixedPoint &Result,
7570	EvalInfo &Info) {
7571	if (E->getType()->isFixedPointType()) {
7572	APValue Val;
7573	if (!FixedPointExprEvaluator(Info, Val).Visit(E))
7574	return false;
7575	if (!Val.isFixedPoint())
7576	return false;
7577
7578	Result = Val.getFixedPoint();
7579	return true;
7580	}
7581	return false;
7582	}
7583
7584	static bool EvaluateFixedPointOrInteger(const Expr *E, APFixedPoint &Result,
7585	EvalInfo &Info) {
7586	if (E->getType()->isIntegerType()) {
7587	auto FXSema = Info.Ctx.getFixedPointSemantics(E->getType());
7588	APSInt Val;
7589	if (!EvaluateInteger(E, Val, Info))
7590	return false;
7591	Result = APFixedPoint(Val, FXSema);
7592	return true;
7593	} else if (E->getType()->isFixedPointType()) {
7594	return EvaluateFixedPoint(E, Result, Info);
7595	}
7596	return false;
7597	}
7598
7599	/// Check whether the given declaration can be directly converted to an integral
7600	/// rvalue. If not, no diagnostic is produced; there are other things we can
7601	/// try.
7602	bool IntExprEvaluator::CheckReferencedDecl(const Expr* E, const Decl* D) {
7603	// Enums are integer constant exprs.
7604	if (const EnumConstantDecl *ECD = dyn_cast<EnumConstantDecl>(D)) {
7605	// Check for signedness/width mismatches between E type and ECD value.
7606	bool SameSign = (ECD->getInitVal().isSigned()
7607	== E->getType()->isSignedIntegerOrEnumerationType());
7608	bool SameWidth = (ECD->getInitVal().getBitWidth()
7609	== Info.Ctx.getIntWidth(E->getType()));
7610	if (SameSign && SameWidth)
7611	return Success(ECD->getInitVal(), E);
7612	else {
7613	// Get rid of mismatch (otherwise Success assertions will fail)
7614	// by computing a new value matching the type of E.
7615	llvm::APSInt Val = ECD->getInitVal();
7616	if (!SameSign)
7617	Val.setIsSigned(!ECD->getInitVal().isSigned());
7618	if (!SameWidth)
7619	Val = Val.extOrTrunc(Info.Ctx.getIntWidth(E->getType()));
7620	return Success(Val, E);
7621	}
7622	}
7623	return false;
7624	}
7625
7626	/// Values returned by __builtin_classify_type, chosen to match the values
7627	/// produced by GCC's builtin.
7628	enum class GCCTypeClass {
7629	None = -1,
7630	Void = 0,
7631	Integer = 1,
7632	// GCC reserves 2 for character types, but instead classifies them as
7633	// integers.
7634	Enum = 3,
7635	Bool = 4,
7636	Pointer = 5,
7637	// GCC reserves 6 for references, but appears to never use it (because
7638	// expressions never have reference type, presumably).
7639	PointerToDataMember = 7,
7640	RealFloat = 8,
7641	Complex = 9,
7642	// GCC reserves 10 for functions, but does not use it since GCC version 6 due
7643	// to decay to pointer. (Prior to version 6 it was only used in C++ mode).
7644	// GCC claims to reserve 11 for pointers to member functions, but actually
7645	// uses 12 for that purpose, same as for a class or struct. Maybe it
7646	// internally implements a pointer to member as a struct? Who knows.
7647	PointerToMemberFunction = 12, // Not a bug, see above.
7648	ClassOrStruct = 12,
7649	Union = 13,
7650	// GCC reserves 14 for arrays, but does not use it since GCC version 6 due to
7651	// decay to pointer. (Prior to version 6 it was only used in C++ mode).
7652	// GCC reserves 15 for strings, but actually uses 5 (pointer) for string
7653	// literals.
7654	};
7655
7656	/// EvaluateBuiltinClassifyType - Evaluate __builtin_classify_type the same way
7657	/// as GCC.
7658	static GCCTypeClass
7659	EvaluateBuiltinClassifyType(QualType T, const LangOptions &LangOpts) {
7660	(0) . __assert_fail ("!T->isDependentType() && \"unexpected dependent type\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 7660, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(!T->isDependentType() && "unexpected dependent type");
7661
7662	QualType CanTy = T.getCanonicalType();
7663	const BuiltinType *BT = dyn_cast<BuiltinType>(CanTy);
7664
7665	switch (CanTy->getTypeClass()) {
7666	#define TYPE(ID, BASE)
7667	#define DEPENDENT_TYPE(ID, BASE) case Type::ID:
7668	#define NON_CANONICAL_TYPE(ID, BASE) case Type::ID:
7669	#define NON_CANONICAL_UNLESS_DEPENDENT_TYPE(ID, BASE) case Type::ID:
7670	#include "clang/AST/TypeNodes.def"
7671	case Type::Auto:
7672	case Type::DeducedTemplateSpecialization:
7673	llvm_unreachable("unexpected non-canonical or dependent type");
7674
7675	case Type::Builtin:
7676	switch (BT->getKind()) {
7677	#define BUILTIN_TYPE(ID, SINGLETON_ID)
7678	#define SIGNED_TYPE(ID, SINGLETON_ID) \
7679	case BuiltinType::ID: return GCCTypeClass::Integer;
7680	#define FLOATING_TYPE(ID, SINGLETON_ID) \
7681	case BuiltinType::ID: return GCCTypeClass::RealFloat;
7682	#define PLACEHOLDER_TYPE(ID, SINGLETON_ID) \
7683	case BuiltinType::ID: break;
7684	#include "clang/AST/BuiltinTypes.def"
7685	case BuiltinType::Void:
7686	return GCCTypeClass::Void;
7687
7688	case BuiltinType::Bool:
7689	return GCCTypeClass::Bool;
7690
7691	case BuiltinType::Char_U:
7692	case BuiltinType::UChar:
7693	case BuiltinType::WChar_U:
7694	case BuiltinType::Char8:
7695	case BuiltinType::Char16:
7696	case BuiltinType::Char32:
7697	case BuiltinType::UShort:
7698	case BuiltinType::UInt:
7699	case BuiltinType::ULong:
7700	case BuiltinType::ULongLong:
7701	case BuiltinType::UInt128:
7702	return GCCTypeClass::Integer;
7703
7704	case BuiltinType::UShortAccum:
7705	case BuiltinType::UAccum:
7706	case BuiltinType::ULongAccum:
7707	case BuiltinType::UShortFract:
7708	case BuiltinType::UFract:
7709	case BuiltinType::ULongFract:
7710	case BuiltinType::SatUShortAccum:
7711	case BuiltinType::SatUAccum:
7712	case BuiltinType::SatULongAccum:
7713	case BuiltinType::SatUShortFract:
7714	case BuiltinType::SatUFract:
7715	case BuiltinType::SatULongFract:
7716	return GCCTypeClass::None;
7717
7718	case BuiltinType::NullPtr:
7719
7720	case BuiltinType::ObjCId:
7721	case BuiltinType::ObjCClass:
7722	case BuiltinType::ObjCSel:
7723	#define IMAGE_TYPE(ImgType, Id, SingletonId, Access, Suffix) \
7724	case BuiltinType::Id:
7725	#include "clang/Basic/OpenCLImageTypes.def"
7726	#define EXT_OPAQUE_TYPE(ExtType, Id, Ext) \
7727	case BuiltinType::Id:
7728	#include "clang/Basic/OpenCLExtensionTypes.def"
7729	case BuiltinType::OCLSampler:
7730	case BuiltinType::OCLEvent:
7731	case BuiltinType::OCLClkEvent:
7732	case BuiltinType::OCLQueue:
7733	case BuiltinType::OCLReserveID:
7734	return GCCTypeClass::None;
7735
7736	case BuiltinType::Dependent:
7737	llvm_unreachable("unexpected dependent type");
7738	};
7739	llvm_unreachable("unexpected placeholder type");
7740
7741	case Type::Enum:
7742	return LangOpts.CPlusPlus ? GCCTypeClass::Enum : GCCTypeClass::Integer;
7743
7744	case Type::Pointer:
7745	case Type::ConstantArray:
7746	case Type::VariableArray:
7747	case Type::IncompleteArray:
7748	case Type::FunctionNoProto:
7749	case Type::FunctionProto:
7750	return GCCTypeClass::Pointer;
7751
7752	case Type::MemberPointer:
7753	return CanTy->isMemberDataPointerType()
7754	? GCCTypeClass::PointerToDataMember
7755	: GCCTypeClass::PointerToMemberFunction;
7756
7757	case Type::Complex:
7758	return GCCTypeClass::Complex;
7759
7760	case Type::Record:
7761	return CanTy->isUnionType() ? GCCTypeClass::Union
7762	: GCCTypeClass::ClassOrStruct;
7763
7764	case Type::Atomic:
7765	// GCC classifies _Atomic T the same as T.
7766	return EvaluateBuiltinClassifyType(
7767	CanTy->castAs<AtomicType>()->getValueType(), LangOpts);
7768
7769	case Type::BlockPointer:
7770	case Type::Vector:
7771	case Type::ExtVector:
7772	case Type::ObjCObject:
7773	case Type::ObjCInterface:
7774	case Type::ObjCObjectPointer:
7775	case Type::Pipe:
7776	// GCC classifies vectors as None. We follow its lead and classify all
7777	// other types that don't fit into the regular classification the same way.
7778	return GCCTypeClass::None;
7779
7780	case Type::LValueReference:
7781	case Type::RValueReference:
7782	llvm_unreachable("invalid type for expression");
7783	}
7784
7785	llvm_unreachable("unexpected type class");
7786	}
7787
7788	/// EvaluateBuiltinClassifyType - Evaluate __builtin_classify_type the same way
7789	/// as GCC.
7790	static GCCTypeClass
7791	EvaluateBuiltinClassifyType(const CallExpr *E, const LangOptions &LangOpts) {
7792	// If no argument was supplied, default to None. This isn't
7793	// ideal, however it is what gcc does.
7794	if (E->getNumArgs() == 0)
7795	return GCCTypeClass::None;
7796
7797	// FIXME: Bizarrely, GCC treats a call with more than one argument as not
7798	// being an ICE, but still folds it to a constant using the type of the first
7799	// argument.
7800	return EvaluateBuiltinClassifyType(E->getArg(0)->getType(), LangOpts);
7801	}
7802
7803	/// EvaluateBuiltinConstantPForLValue - Determine the result of
7804	/// __builtin_constant_p when applied to the given lvalue.
7805	///
7806	/// An lvalue is only "constant" if it is a pointer or reference to the first
7807	/// character of a string literal.
7808	template<typename LValue>
7809	static bool EvaluateBuiltinConstantPForLValue(const LValue &LV) {
7810	const Expr E = LV.getLValueBase().template dyn_cast<const Expr>();
7811	return E && isa<StringLiteral>(E) && LV.getLValueOffset().isZero();
7812	}
7813
7814	/// EvaluateBuiltinConstantP - Evaluate __builtin_constant_p as similarly to
7815	/// GCC as we can manage.
7816	static bool EvaluateBuiltinConstantP(ASTContext &Ctx, const Expr *Arg) {
7817	QualType ArgType = Arg->getType();
7818
7819	// __builtin_constant_p always has one operand. The rules which gcc follows
7820	// are not precisely documented, but are as follows:
7821	//
7822	// - If the operand is of integral, floating, complex or enumeration type,
7823	// and can be folded to a known value of that type, it returns 1.
7824	// - If the operand and can be folded to a pointer to the first character
7825	// of a string literal (or such a pointer cast to an integral type), it
7826	// returns 1.
7827	//
7828	// Otherwise, it returns 0.
7829	//
7830	// FIXME: GCC also intends to return 1 for literals of aggregate types, but
7831	// its support for this does not currently work.
7832	if (ArgType->isIntegralOrEnumerationType()) {
7833	Expr::EvalResult Result;
7834	if (!Arg->EvaluateAsRValue(Result, Ctx) \|\| Result.HasSideEffects)
7835	return false;
7836
7837	APValue &V = Result.Val;
7838	if (V.getKind() == APValue::Int)
7839	return true;
7840	if (V.getKind() == APValue::LValue)
7841	return EvaluateBuiltinConstantPForLValue(V);
7842	} else if (ArgType->isFloatingType() \|\| ArgType->isAnyComplexType()) {
7843	return Arg->isEvaluatable(Ctx);
7844	} else if (ArgType->isPointerType() \|\| Arg->isGLValue()) {
7845	LValue LV;
7846	Expr::EvalStatus Status;
7847	EvalInfo Info(Ctx, Status, EvalInfo::EM_ConstantFold);
7848	if ((Arg->isGLValue() ? EvaluateLValue(Arg, LV, Info)
7849	: EvaluatePointer(Arg, LV, Info)) &&
7850	!Status.HasSideEffects)
7851	return EvaluateBuiltinConstantPForLValue(LV);
7852	}
7853
7854	// Anything else isn't considered to be sufficiently constant.
7855	return false;
7856	}
7857
7858	/// Retrieves the "underlying object type" of the given expression,
7859	/// as used by __builtin_object_size.
7860	static QualType getObjectType(APValue::LValueBase B) {
7861	if (const ValueDecl D = B.dyn_cast<const ValueDecl>()) {
7862	if (const VarDecl *VD = dyn_cast<VarDecl>(D))
7863	return VD->getType();
7864	} else if (const Expr E = B.get<const Expr>()) {
7865	if (isa<CompoundLiteralExpr>(E))
7866	return E->getType();
7867	}
7868
7869	return QualType();
7870	}
7871
7872	/// A more selective version of E->IgnoreParenCasts for
7873	/// tryEvaluateBuiltinObjectSize. This ignores some casts/parens that serve only
7874	/// to change the type of E.
7875	/// Ex. For E = `(short)((char)(&foo))`, returns `&foo`
7876	///
7877	/// Always returns an RValue with a pointer representation.
7878	static const Expr ignorePointerCastsAndParens(const Expr E) {
7879	isRValue() && E->getType()->hasPointerRepresentation()", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 7879, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(E->isRValue() && E->getType()->hasPointerRepresentation());
7880
7881	auto *NoParens = E->IgnoreParens();
7882	auto *Cast = dyn_cast<CastExpr>(NoParens);
7883	if (Cast == nullptr)
7884	return NoParens;
7885
7886	// We only conservatively allow a few kinds of casts, because this code is
7887	// inherently a simple solution that seeks to support the common case.
7888	auto CastKind = Cast->getCastKind();
7889	if (CastKind != CK_NoOp && CastKind != CK_BitCast &&
7890	CastKind != CK_AddressSpaceConversion)
7891	return NoParens;
7892
7893	auto *SubExpr = Cast->getSubExpr();
7894	if (!SubExpr->getType()->hasPointerRepresentation() \|\| !SubExpr->isRValue())
7895	return NoParens;
7896	return ignorePointerCastsAndParens(SubExpr);
7897	}
7898
7899	/// Checks to see if the given LValue's Designator is at the end of the LValue's
7900	/// record layout. e.g.
7901	/// struct { struct { int a, b; } fst, snd; } obj;
7902	/// obj.fst // no
7903	/// obj.snd // yes
7904	/// obj.fst.a // no
7905	/// obj.fst.b // no
7906	/// obj.snd.a // no
7907	/// obj.snd.b // yes
7908	///
7909	/// Please note: this function is specialized for how __builtin_object_size
7910	/// views "objects".
7911	///
7912	/// If this encounters an invalid RecordDecl or otherwise cannot determine the
7913	/// correct result, it will always return true.
7914	static bool isDesignatorAtObjectEnd(const ASTContext &Ctx, const LValue &LVal) {
7915	assert(!LVal.Designator.Invalid);
7916
7917	auto IsLastOrInvalidFieldDecl = [&Ctx](const FieldDecl *FD, bool &Invalid) {
7918	const RecordDecl *Parent = FD->getParent();
7919	Invalid = Parent->isInvalidDecl();
7920	if (Invalid \|\| Parent->isUnion())
7921	return true;
7922	const ASTRecordLayout &Layout = Ctx.getASTRecordLayout(Parent);
7923	return FD->getFieldIndex() + 1 == Layout.getFieldCount();
7924	};
7925
7926	auto &Base = LVal.getLValueBase();
7927	if (auto ME = dyn_cast_or_null<MemberExpr>(Base.dyn_cast<const Expr >())) {
7928	if (auto *FD = dyn_cast<FieldDecl>(ME->getMemberDecl())) {
7929	bool Invalid;
7930	if (!IsLastOrInvalidFieldDecl(FD, Invalid))
7931	return Invalid;
7932	} else if (auto *IFD = dyn_cast<IndirectFieldDecl>(ME->getMemberDecl())) {
7933	for (auto *FD : IFD->chain()) {
7934	bool Invalid;
7935	if (!IsLastOrInvalidFieldDecl(cast<FieldDecl>(FD), Invalid))
7936	return Invalid;
7937	}
7938	}
7939	}
7940
7941	unsigned I = 0;
7942	QualType BaseType = getType(Base);
7943	if (LVal.Designator.FirstEntryIsAnUnsizedArray) {
7944	// If we don't know the array bound, conservatively assume we're looking at
7945	// the final array element.
7946	++I;
7947	if (BaseType->isIncompleteArrayType())
7948	BaseType = Ctx.getAsArrayType(BaseType)->getElementType();
7949	else
7950	BaseType = BaseType->castAs<PointerType>()->getPointeeType();
7951	}
7952
7953	for (unsigned E = LVal.Designator.Entries.size(); I != E; ++I) {
7954	const auto &Entry = LVal.Designator.Entries[I];
7955	if (BaseType->isArrayType()) {
7956	// Because __builtin_object_size treats arrays as objects, we can ignore
7957	// the index iff this is the last array in the Designator.
7958	if (I + 1 == E)
7959	return true;
7960	const auto *CAT = cast<ConstantArrayType>(Ctx.getAsArrayType(BaseType));
7961	uint64_t Index = Entry.ArrayIndex;
7962	if (Index + 1 != CAT->getSize())
7963	return false;
7964	BaseType = CAT->getElementType();
7965	} else if (BaseType->isAnyComplexType()) {
7966	const auto *CT = BaseType->castAs<ComplexType>();
7967	uint64_t Index = Entry.ArrayIndex;
7968	if (Index != 1)
7969	return false;
7970	BaseType = CT->getElementType();
7971	} else if (auto *FD = getAsField(Entry)) {
7972	bool Invalid;
7973	if (!IsLastOrInvalidFieldDecl(FD, Invalid))
7974	return Invalid;
7975	BaseType = FD->getType();
7976	} else {
7977	(0) . __assert_fail ("getAsBaseClass(Entry) && \"Expecting cast to a base class\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 7977, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(getAsBaseClass(Entry) && "Expecting cast to a base class");
7978	return false;
7979	}
7980	}
7981	return true;
7982	}
7983
7984	/// Tests to see if the LValue has a user-specified designator (that isn't
7985	/// necessarily valid). Note that this always returns 'true' if the LValue has
7986	/// an unsized array as its first designator entry, because there's currently no
7987	/// way to tell if the user typed *foo or foo[0].
7988	static bool refersToCompleteObject(const LValue &LVal) {
7989	if (LVal.Designator.Invalid)
7990	return false;
7991
7992	if (!LVal.Designator.Entries.empty())
7993	return LVal.Designator.isMostDerivedAnUnsizedArray();
7994
7995	if (!LVal.InvalidBase)
7996	return true;
7997
7998	// If `E` is a MemberExpr, then the first part of the designator is hiding in
7999	// the LValueBase.
8000	const auto E = LVal.Base.dyn_cast<const Expr >();
8001	return !E \|\| !isa<MemberExpr>(E);
8002	}
8003
8004	/// Attempts to detect a user writing into a piece of memory that's impossible
8005	/// to figure out the size of by just using types.
8006	static bool isUserWritingOffTheEnd(const ASTContext &Ctx, const LValue &LVal) {
8007	const SubobjectDesignator &Designator = LVal.Designator;
8008	// Notes:
8009	// - Users can only write off of the end when we have an invalid base. Invalid
8010	// bases imply we don't know where the memory came from.
8011	// - We used to be a bit more aggressive here; we'd only be conservative if
8012	// the array at the end was flexible, or if it had 0 or 1 elements. This
8013	// broke some common standard library extensions (PR30346), but was
8014	// otherwise seemingly fine. It may be useful to reintroduce this behavior
8015	// with some sort of whitelist. OTOH, it seems that GCC is always
8016	// conservative with the last element in structs (if it's an array), so our
8017	// current behavior is more compatible than a whitelisting approach would
8018	// be.
8019	return LVal.InvalidBase &&
8020	Designator.Entries.size() == Designator.MostDerivedPathLength &&
8021	Designator.MostDerivedIsArrayElement &&
8022	isDesignatorAtObjectEnd(Ctx, LVal);
8023	}
8024
8025	/// Converts the given APInt to CharUnits, assuming the APInt is unsigned.
8026	/// Fails if the conversion would cause loss of precision.
8027	static bool convertUnsignedAPIntToCharUnits(const llvm::APInt &Int,
8028	CharUnits &Result) {
8029	auto CharUnitsMax = std::numeric_limits<CharUnits::QuantityType>::max();
8030	if (Int.ugt(CharUnitsMax))
8031	return false;
8032	Result = CharUnits::fromQuantity(Int.getZExtValue());
8033	return true;
8034	}
8035
8036	/// Helper for tryEvaluateBuiltinObjectSize -- Given an LValue, this will
8037	/// determine how many bytes exist from the beginning of the object to either
8038	/// the end of the current subobject, or the end of the object itself, depending
8039	/// on what the LValue looks like + the value of Type.
8040	///
8041	/// If this returns false, the value of Result is undefined.
8042	static bool determineEndOffset(EvalInfo &Info, SourceLocation ExprLoc,
8043	unsigned Type, const LValue &LVal,
8044	CharUnits &EndOffset) {
8045	bool DetermineForCompleteObject = refersToCompleteObject(LVal);
8046
8047	auto CheckedHandleSizeof = [&](QualType Ty, CharUnits &Result) {
8048	if (Ty.isNull() \|\| Ty->isIncompleteType() \|\| Ty->isFunctionType())
8049	return false;
8050	return HandleSizeof(Info, ExprLoc, Ty, Result);
8051	};
8052
8053	// We want to evaluate the size of the entire object. This is a valid fallback
8054	// for when Type=1 and the designator is invalid, because we're asked for an
8055	// upper-bound.
8056	if (!(Type & 1) \|\| LVal.Designator.Invalid \|\| DetermineForCompleteObject) {
8057	// Type=3 wants a lower bound, so we can't fall back to this.
8058	if (Type == 3 && !DetermineForCompleteObject)
8059	return false;
8060
8061	llvm::APInt APEndOffset;
8062	if (isBaseAnAllocSizeCall(LVal.getLValueBase()) &&
8063	getBytesReturnedByAllocSizeCall(Info.Ctx, LVal, APEndOffset))
8064	return convertUnsignedAPIntToCharUnits(APEndOffset, EndOffset);
8065
8066	if (LVal.InvalidBase)
8067	return false;
8068
8069	QualType BaseTy = getObjectType(LVal.getLValueBase());
8070	return CheckedHandleSizeof(BaseTy, EndOffset);
8071	}
8072
8073	// We want to evaluate the size of a subobject.
8074	const SubobjectDesignator &Designator = LVal.Designator;
8075
8076	// The following is a moderately common idiom in C:
8077	//
8078	// struct Foo { int a; char c[1]; };
8079	// struct Foo F = (struct Foo )malloc(sizeof(struct Foo) + strlen(Bar));
8080	// strcpy(&F->c[0], Bar);
8081	//
8082	// In order to not break too much legacy code, we need to support it.
8083	if (isUserWritingOffTheEnd(Info.Ctx, LVal)) {
8084	// If we can resolve this to an alloc_size call, we can hand that back,
8085	// because we know for certain how many bytes there are to write to.
8086	llvm::APInt APEndOffset;
8087	if (isBaseAnAllocSizeCall(LVal.getLValueBase()) &&
8088	getBytesReturnedByAllocSizeCall(Info.Ctx, LVal, APEndOffset))
8089	return convertUnsignedAPIntToCharUnits(APEndOffset, EndOffset);
8090
8091	// If we cannot determine the size of the initial allocation, then we can't
8092	// given an accurate upper-bound. However, we are still able to give
8093	// conservative lower-bounds for Type=3.
8094	if (Type == 1)
8095	return false;
8096	}
8097
8098	CharUnits BytesPerElem;
8099	if (!CheckedHandleSizeof(Designator.MostDerivedType, BytesPerElem))
8100	return false;
8101
8102	// According to the GCC documentation, we want the size of the subobject
8103	// denoted by the pointer. But that's not quite right -- what we actually
8104	// want is the size of the immediately-enclosing array, if there is one.
8105	int64_t ElemsRemaining;
8106	if (Designator.MostDerivedIsArrayElement &&
8107	Designator.Entries.size() == Designator.MostDerivedPathLength) {
8108	uint64_t ArraySize = Designator.getMostDerivedArraySize();
8109	uint64_t ArrayIndex = Designator.Entries.back().ArrayIndex;
8110	ElemsRemaining = ArraySize <= ArrayIndex ? 0 : ArraySize - ArrayIndex;
8111	} else {
8112	ElemsRemaining = Designator.isOnePastTheEnd() ? 0 : 1;
8113	}
8114
8115	EndOffset = LVal.getLValueOffset() + BytesPerElem * ElemsRemaining;
8116	return true;
8117	}
8118
8119	/// Tries to evaluate the __builtin_object_size for @p E. If successful,
8120	/// returns true and stores the result in @p Size.
8121	///
8122	/// If @p WasError is non-null, this will report whether the failure to evaluate
8123	/// is to be treated as an Error in IntExprEvaluator.
8124	static bool tryEvaluateBuiltinObjectSize(const Expr *E, unsigned Type,
8125	EvalInfo &Info, uint64_t &Size) {
8126	// Determine the denoted object.
8127	LValue LVal;
8128	{
8129	// The operand of __builtin_object_size is never evaluated for side-effects.
8130	// If there are any, but we can determine the pointed-to object anyway, then
8131	// ignore the side-effects.
8132	SpeculativeEvaluationRAII SpeculativeEval(Info);
8133	IgnoreSideEffectsRAII Fold(Info);
8134
8135	if (E->isGLValue()) {
8136	// It's possible for us to be given GLValues if we're called via
8137	// Expr::tryEvaluateObjectSize.
8138	APValue RVal;
8139	if (!EvaluateAsRValue(Info, E, RVal))
8140	return false;
8141	LVal.setFrom(Info.Ctx, RVal);
8142	} else if (!EvaluatePointer(ignorePointerCastsAndParens(E), LVal, Info,
8143	/InvalidBaseOK=/true))
8144	return false;
8145	}
8146
8147	// If we point to before the start of the object, there are no accessible
8148	// bytes.
8149	if (LVal.getLValueOffset().isNegative()) {
8150	Size = 0;
8151	return true;
8152	}
8153
8154	CharUnits EndOffset;
8155	if (!determineEndOffset(Info, E->getExprLoc(), Type, LVal, EndOffset))
8156	return false;
8157
8158	// If we've fallen outside of the end offset, just pretend there's nothing to
8159	// write to/read from.
8160	if (EndOffset <= LVal.getLValueOffset())
8161	Size = 0;
8162	else
8163	Size = (EndOffset - LVal.getLValueOffset()).getQuantity();
8164	return true;
8165	}
8166
8167	bool IntExprEvaluator::VisitConstantExpr(const ConstantExpr *E) {
8168	llvm::SaveAndRestore<bool> InConstantContext(Info.InConstantContext, true);
8169	return ExprEvaluatorBaseTy::VisitConstantExpr(E);
8170	}
8171
8172	bool IntExprEvaluator::VisitCallExpr(const CallExpr *E) {
8173	if (unsigned BuiltinOp = E->getBuiltinCallee())
8174	return VisitBuiltinCallExpr(E, BuiltinOp);
8175
8176	return ExprEvaluatorBaseTy::VisitCallExpr(E);
8177	}
8178
8179	bool IntExprEvaluator::VisitBuiltinCallExpr(const CallExpr *E,
8180	unsigned BuiltinOp) {
8181	switch (unsigned BuiltinOp = E->getBuiltinCallee()) {
8182	default:
8183	return ExprEvaluatorBaseTy::VisitCallExpr(E);
8184
8185	case Builtin::BI__builtin_dynamic_object_size:
8186	case Builtin::BI__builtin_object_size: {
8187	// The type was checked when we built the expression.
8188	unsigned Type =
8189	E->getArg(1)->EvaluateKnownConstInt(Info.Ctx).getZExtValue();
8190	(0) . __assert_fail ("Type <= 3 && \"unexpected type\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 8190, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(Type <= 3 && "unexpected type");
8191
8192	uint64_t Size;
8193	if (tryEvaluateBuiltinObjectSize(E->getArg(0), Type, Info, Size))
8194	return Success(Size, E);
8195
8196	if (E->getArg(0)->HasSideEffects(Info.Ctx))
8197	return Success((Type & 2) ? 0 : -1, E);
8198
8199	// Expression had no side effects, but we couldn't statically determine the
8200	// size of the referenced object.
8201	switch (Info.EvalMode) {
8202	case EvalInfo::EM_ConstantExpression:
8203	case EvalInfo::EM_PotentialConstantExpression:
8204	case EvalInfo::EM_ConstantFold:
8205	case EvalInfo::EM_EvaluateForOverflow:
8206	case EvalInfo::EM_IgnoreSideEffects:
8207	// Leave it to IR generation.
8208	return Error(E);
8209	case EvalInfo::EM_ConstantExpressionUnevaluated:
8210	case EvalInfo::EM_PotentialConstantExpressionUnevaluated:
8211	// Reduce it to a constant now.
8212	return Success((Type & 2) ? 0 : -1, E);
8213	}
8214
8215	llvm_unreachable("unexpected EvalMode");
8216	}
8217
8218	case Builtin::BI__builtin_os_log_format_buffer_size: {
8219	analyze_os_log::OSLogBufferLayout Layout;
8220	analyze_os_log::computeOSLogBufferLayout(Info.Ctx, E, Layout);
8221	return Success(Layout.size().getQuantity(), E);
8222	}
8223
8224	case Builtin::BI__builtin_bswap16:
8225	case Builtin::BI__builtin_bswap32:
8226	case Builtin::BI__builtin_bswap64: {
8227	APSInt Val;
8228	if (!EvaluateInteger(E->getArg(0), Val, Info))
8229	return false;
8230
8231	return Success(Val.byteSwap(), E);
8232	}
8233
8234	case Builtin::BI__builtin_classify_type:
8235	return Success((int)EvaluateBuiltinClassifyType(E, Info.getLangOpts()), E);
8236
8237	case Builtin::BI__builtin_clrsb:
8238	case Builtin::BI__builtin_clrsbl:
8239	case Builtin::BI__builtin_clrsbll: {
8240	APSInt Val;
8241	if (!EvaluateInteger(E->getArg(0), Val, Info))
8242	return false;
8243
8244	return Success(Val.getBitWidth() - Val.getMinSignedBits(), E);
8245	}
8246
8247	case Builtin::BI__builtin_clz:
8248	case Builtin::BI__builtin_clzl:
8249	case Builtin::BI__builtin_clzll:
8250	case Builtin::BI__builtin_clzs: {
8251	APSInt Val;
8252	if (!EvaluateInteger(E->getArg(0), Val, Info))
8253	return false;
8254	if (!Val)
8255	return Error(E);
8256
8257	return Success(Val.countLeadingZeros(), E);
8258	}
8259
8260	case Builtin::BI__builtin_constant_p: {
8261	auto Arg = E->getArg(0);
8262	if (EvaluateBuiltinConstantP(Info.Ctx, Arg))
8263	return Success(true, E);
8264	auto ArgTy = Arg->IgnoreImplicit()->getType();
8265	if (!Info.InConstantContext && !Arg->HasSideEffects(Info.Ctx) &&
8266	!ArgTy->isAggregateType() && !ArgTy->isPointerType()) {
8267	// We can delay calculation of __builtin_constant_p until after
8268	// inlining. Note: This diagnostic won't be shown to the user.
8269	Info.FFDiag(E, diag::note_invalid_subexpr_in_const_expr);
8270	return false;
8271	}
8272	return Success(false, E);
8273	}
8274
8275	case Builtin::BI__builtin_ctz:
8276	case Builtin::BI__builtin_ctzl:
8277	case Builtin::BI__builtin_ctzll:
8278	case Builtin::BI__builtin_ctzs: {
8279	APSInt Val;
8280	if (!EvaluateInteger(E->getArg(0), Val, Info))
8281	return false;
8282	if (!Val)
8283	return Error(E);
8284
8285	return Success(Val.countTrailingZeros(), E);
8286	}
8287
8288	case Builtin::BI__builtin_eh_return_data_regno: {
8289	int Operand = E->getArg(0)->EvaluateKnownConstInt(Info.Ctx).getZExtValue();
8290	Operand = Info.Ctx.getTargetInfo().getEHDataRegisterNumber(Operand);
8291	return Success(Operand, E);
8292	}
8293
8294	case Builtin::BI__builtin_expect:
8295	return Visit(E->getArg(0));
8296
8297	case Builtin::BI__builtin_ffs:
8298	case Builtin::BI__builtin_ffsl:
8299	case Builtin::BI__builtin_ffsll: {
8300	APSInt Val;
8301	if (!EvaluateInteger(E->getArg(0), Val, Info))
8302	return false;
8303
8304	unsigned N = Val.countTrailingZeros();
8305	return Success(N == Val.getBitWidth() ? 0 : N + 1, E);
8306	}
8307
8308	case Builtin::BI__builtin_fpclassify: {
8309	APFloat Val(0.0);
8310	if (!EvaluateFloat(E->getArg(5), Val, Info))
8311	return false;
8312	unsigned Arg;
8313	switch (Val.getCategory()) {
8314	case APFloat::fcNaN: Arg = 0; break;
8315	case APFloat::fcInfinity: Arg = 1; break;
8316	case APFloat::fcNormal: Arg = Val.isDenormal() ? 3 : 2; break;
8317	case APFloat::fcZero: Arg = 4; break;
8318	}
8319	return Visit(E->getArg(Arg));
8320	}
8321
8322	case Builtin::BI__builtin_isinf_sign: {
8323	APFloat Val(0.0);
8324	return EvaluateFloat(E->getArg(0), Val, Info) &&
8325	Success(Val.isInfinity() ? (Val.isNegative() ? -1 : 1) : 0, E);
8326	}
8327
8328	case Builtin::BI__builtin_isinf: {
8329	APFloat Val(0.0);
8330	return EvaluateFloat(E->getArg(0), Val, Info) &&
8331	Success(Val.isInfinity() ? 1 : 0, E);
8332	}
8333
8334	case Builtin::BI__builtin_isfinite: {
8335	APFloat Val(0.0);
8336	return EvaluateFloat(E->getArg(0), Val, Info) &&
8337	Success(Val.isFinite() ? 1 : 0, E);
8338	}
8339
8340	case Builtin::BI__builtin_isnan: {
8341	APFloat Val(0.0);
8342	return EvaluateFloat(E->getArg(0), Val, Info) &&
8343	Success(Val.isNaN() ? 1 : 0, E);
8344	}
8345
8346	case Builtin::BI__builtin_isnormal: {
8347	APFloat Val(0.0);
8348	return EvaluateFloat(E->getArg(0), Val, Info) &&
8349	Success(Val.isNormal() ? 1 : 0, E);
8350	}
8351
8352	case Builtin::BI__builtin_parity:
8353	case Builtin::BI__builtin_parityl:
8354	case Builtin::BI__builtin_parityll: {
8355	APSInt Val;
8356	if (!EvaluateInteger(E->getArg(0), Val, Info))
8357	return false;
8358
8359	return Success(Val.countPopulation() % 2, E);
8360	}
8361
8362	case Builtin::BI__builtin_popcount:
8363	case Builtin::BI__builtin_popcountl:
8364	case Builtin::BI__builtin_popcountll: {
8365	APSInt Val;
8366	if (!EvaluateInteger(E->getArg(0), Val, Info))
8367	return false;
8368
8369	return Success(Val.countPopulation(), E);
8370	}
8371
8372	case Builtin::BIstrlen:
8373	case Builtin::BIwcslen:
8374	// A call to strlen is not a constant expression.
8375	if (Info.getLangOpts().CPlusPlus11)
8376	Info.CCEDiag(E, diag::note_constexpr_invalid_function)
8377	<< /isConstexpr/0 << /isConstructor/0
8378	<< (std::string("'") + Info.Ctx.BuiltinInfo.getName(BuiltinOp) + "'");
8379	else
8380	Info.CCEDiag(E, diag::note_invalid_subexpr_in_const_expr);
8381	LLVM_FALLTHROUGH;
8382	case Builtin::BI__builtin_strlen:
8383	case Builtin::BI__builtin_wcslen: {
8384	// As an extension, we support __builtin_strlen() as a constant expression,
8385	// and support folding strlen() to a constant.
8386	LValue String;
8387	if (!EvaluatePointer(E->getArg(0), String, Info))
8388	return false;
8389
8390	QualType CharTy = E->getArg(0)->getType()->getPointeeType();
8391
8392	// Fast path: if it's a string literal, search the string value.
8393	if (const StringLiteral *S = dyn_cast_or_null<StringLiteral>(
8394	String.getLValueBase().dyn_cast<const Expr *>())) {
8395	// The string literal may have embedded null characters. Find the first
8396	// one and truncate there.
8397	StringRef Str = S->getBytes();
8398	int64_t Off = String.Offset.getQuantity();
8399	if (Off >= 0 && (uint64_t)Off <= (uint64_t)Str.size() &&
8400	S->getCharByteWidth() == 1 &&
8401	// FIXME: Add fast-path for wchar_t too.
8402	Info.Ctx.hasSameUnqualifiedType(CharTy, Info.Ctx.CharTy)) {
8403	Str = Str.substr(Off);
8404
8405	StringRef::size_type Pos = Str.find(0);
8406	if (Pos != StringRef::npos)
8407	Str = Str.substr(0, Pos);
8408
8409	return Success(Str.size(), E);
8410	}
8411
8412	// Fall through to slow path to issue appropriate diagnostic.
8413	}
8414
8415	// Slow path: scan the bytes of the string looking for the terminating 0.
8416	for (uint64_t Strlen = 0; /**/; ++Strlen) {
8417	APValue Char;
8418	if (!handleLValueToRValueConversion(Info, E, CharTy, String, Char) \|\|
8419	!Char.isInt())
8420	return false;
8421	if (!Char.getInt())
8422	return Success(Strlen, E);
8423	if (!HandleLValueArrayAdjustment(Info, E, String, CharTy, 1))
8424	return false;
8425	}
8426	}
8427
8428	case Builtin::BIstrcmp:
8429	case Builtin::BIwcscmp:
8430	case Builtin::BIstrncmp:
8431	case Builtin::BIwcsncmp:
8432	case Builtin::BImemcmp:
8433	case Builtin::BIbcmp:
8434	case Builtin::BIwmemcmp:
8435	// A call to strlen is not a constant expression.
8436	if (Info.getLangOpts().CPlusPlus11)
8437	Info.CCEDiag(E, diag::note_constexpr_invalid_function)
8438	<< /isConstexpr/0 << /isConstructor/0
8439	<< (std::string("'") + Info.Ctx.BuiltinInfo.getName(BuiltinOp) + "'");
8440	else
8441	Info.CCEDiag(E, diag::note_invalid_subexpr_in_const_expr);
8442	LLVM_FALLTHROUGH;
8443	case Builtin::BI__builtin_strcmp:
8444	case Builtin::BI__builtin_wcscmp:
8445	case Builtin::BI__builtin_strncmp:
8446	case Builtin::BI__builtin_wcsncmp:
8447	case Builtin::BI__builtin_memcmp:
8448	case Builtin::BI__builtin_bcmp:
8449	case Builtin::BI__builtin_wmemcmp: {
8450	LValue String1, String2;
8451	if (!EvaluatePointer(E->getArg(0), String1, Info) \|\|
8452	!EvaluatePointer(E->getArg(1), String2, Info))
8453	return false;
8454
8455	uint64_t MaxLength = uint64_t(-1);
8456	if (BuiltinOp != Builtin::BIstrcmp &&
8457	BuiltinOp != Builtin::BIwcscmp &&
8458	BuiltinOp != Builtin::BI__builtin_strcmp &&
8459	BuiltinOp != Builtin::BI__builtin_wcscmp) {
8460	APSInt N;
8461	if (!EvaluateInteger(E->getArg(2), N, Info))
8462	return false;
8463	MaxLength = N.getExtValue();
8464	}
8465
8466	// Empty substrings compare equal by definition.
8467	if (MaxLength == 0u)
8468	return Success(0, E);
8469
8470	if (!String1.checkNullPointerForFoldAccess(Info, E, AK_Read) \|\|
8471	!String2.checkNullPointerForFoldAccess(Info, E, AK_Read) \|\|
8472	String1.Designator.Invalid \|\| String2.Designator.Invalid)
8473	return false;
8474
8475	QualType CharTy1 = String1.Designator.getType(Info.Ctx);
8476	QualType CharTy2 = String2.Designator.getType(Info.Ctx);
8477
8478	bool IsRawByte = BuiltinOp == Builtin::BImemcmp \|\|
8479	BuiltinOp == Builtin::BIbcmp \|\|
8480	BuiltinOp == Builtin::BI__builtin_memcmp \|\|
8481	BuiltinOp == Builtin::BI__builtin_bcmp;
8482
8483	getArg(0)->getType()->getPointeeType()) && Info.Ctx.hasSameUnqualifiedType(CharTy1, CharTy2))", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 8486, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(IsRawByte \|\|
8484	getArg(0)->getType()->getPointeeType()) && Info.Ctx.hasSameUnqualifiedType(CharTy1, CharTy2))", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 8486, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true"> (Info.Ctx.hasSameUnqualifiedType(
8485	getArg(0)->getType()->getPointeeType()) && Info.Ctx.hasSameUnqualifiedType(CharTy1, CharTy2))", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 8486, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true"> CharTy1, E->getArg(0)->getType()->getPointeeType()) &&
8486	getArg(0)->getType()->getPointeeType()) && Info.Ctx.hasSameUnqualifiedType(CharTy1, CharTy2))", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 8486, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true"> Info.Ctx.hasSameUnqualifiedType(CharTy1, CharTy2)));
8487
8488	const auto &ReadCurElems = [&](APValue &Char1, APValue &Char2) {
8489	return handleLValueToRValueConversion(Info, E, CharTy1, String1, Char1) &&
8490	handleLValueToRValueConversion(Info, E, CharTy2, String2, Char2) &&
8491	Char1.isInt() && Char2.isInt();
8492	};
8493	const auto &AdvanceElems = [&] {
8494	return HandleLValueArrayAdjustment(Info, E, String1, CharTy1, 1) &&
8495	HandleLValueArrayAdjustment(Info, E, String2, CharTy2, 1);
8496	};
8497
8498	if (IsRawByte) {
8499	uint64_t BytesRemaining = MaxLength;
8500	// Pointers to const void may point to objects of incomplete type.
8501	if (CharTy1->isIncompleteType()) {
8502	Info.FFDiag(E, diag::note_constexpr_ltor_incomplete_type) << CharTy1;
8503	return false;
8504	}
8505	if (CharTy2->isIncompleteType()) {
8506	Info.FFDiag(E, diag::note_constexpr_ltor_incomplete_type) << CharTy2;
8507	return false;
8508	}
8509	uint64_t CharTy1Width{Info.Ctx.getTypeSize(CharTy1)};
8510	CharUnits CharTy1Size = Info.Ctx.toCharUnitsFromBits(CharTy1Width);
8511	// Give up on comparing between elements with disparate widths.
8512	if (CharTy1Size != Info.Ctx.getTypeSizeInChars(CharTy2))
8513	return false;
8514	uint64_t BytesPerElement = CharTy1Size.getQuantity();
8515	(0) . __assert_fail ("BytesRemaining && \"BytesRemaining should not be zero. the \" \"following loop considers at least one element\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 8516, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(BytesRemaining && "BytesRemaining should not be zero: the "
8516	(0) . __assert_fail ("BytesRemaining && \"BytesRemaining should not be zero. the \" \"following loop considers at least one element\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 8516, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true"> "following loop considers at least one element");
8517	while (true) {
8518	APValue Char1, Char2;
8519	if (!ReadCurElems(Char1, Char2))
8520	return false;
8521	// We have compatible in-memory widths, but a possible type and
8522	// (for `bool`) internal representation mismatch.
8523	// Assuming two's complement representation, including 0 for `false` and
8524	// 1 for `true`, we can check an appropriate number of elements for
8525	// equality even if they are not byte-sized.
8526	APSInt Char1InMem = Char1.getInt().extOrTrunc(CharTy1Width);
8527	APSInt Char2InMem = Char2.getInt().extOrTrunc(CharTy1Width);
8528	if (Char1InMem.ne(Char2InMem)) {
8529	// If the elements are byte-sized, then we can produce a three-way
8530	// comparison result in a straightforward manner.
8531	if (BytesPerElement == 1u) {
8532	// memcmp always compares unsigned chars.
8533	return Success(Char1InMem.ult(Char2InMem) ? -1 : 1, E);
8534	}
8535	// The result is byte-order sensitive, and we have multibyte elements.
8536	// FIXME: We can compare the remaining bytes in the correct order.
8537	return false;
8538	}
8539	if (!AdvanceElems())
8540	return false;
8541	if (BytesRemaining <= BytesPerElement)
8542	break;
8543	BytesRemaining -= BytesPerElement;
8544	}
8545	// Enough elements are equal to account for the memcmp limit.
8546	return Success(0, E);
8547	}
8548
8549	bool StopAtNull =
8550	(BuiltinOp != Builtin::BImemcmp && BuiltinOp != Builtin::BIbcmp &&
8551	BuiltinOp != Builtin::BIwmemcmp &&
8552	BuiltinOp != Builtin::BI__builtin_memcmp &&
8553	BuiltinOp != Builtin::BI__builtin_bcmp &&
8554	BuiltinOp != Builtin::BI__builtin_wmemcmp);
8555	bool IsWide = BuiltinOp == Builtin::BIwcscmp \|\|
8556	BuiltinOp == Builtin::BIwcsncmp \|\|
8557	BuiltinOp == Builtin::BIwmemcmp \|\|
8558	BuiltinOp == Builtin::BI__builtin_wcscmp \|\|
8559	BuiltinOp == Builtin::BI__builtin_wcsncmp \|\|
8560	BuiltinOp == Builtin::BI__builtin_wmemcmp;
8561
8562	for (; MaxLength; --MaxLength) {
8563	APValue Char1, Char2;
8564	if (!ReadCurElems(Char1, Char2))
8565	return false;
8566	if (Char1.getInt() != Char2.getInt()) {
8567	if (IsWide) // wmemcmp compares with wchar_t signedness.
8568	return Success(Char1.getInt() < Char2.getInt() ? -1 : 1, E);
8569	// memcmp always compares unsigned chars.
8570	return Success(Char1.getInt().ult(Char2.getInt()) ? -1 : 1, E);
8571	}
8572	if (StopAtNull && !Char1.getInt())
8573	return Success(0, E);
8574	assert(!(StopAtNull && !Char2.getInt()));
8575	if (!AdvanceElems())
8576	return false;
8577	}
8578	// We hit the strncmp / memcmp limit.
8579	return Success(0, E);
8580	}
8581
8582	case Builtin::BI__atomic_always_lock_free:
8583	case Builtin::BI__atomic_is_lock_free:
8584	case Builtin::BI__c11_atomic_is_lock_free: {
8585	APSInt SizeVal;
8586	if (!EvaluateInteger(E->getArg(0), SizeVal, Info))
8587	return false;
8588
8589	// For __atomic_is_lock_free(sizeof(_Atomic(T))), if the size is a power
8590	// of two less than the maximum inline atomic width, we know it is
8591	// lock-free. If the size isn't a power of two, or greater than the
8592	// maximum alignment where we promote atomics, we know it is not lock-free
8593	// (at least not in the sense of atomic_is_lock_free). Otherwise,
8594	// the answer can only be determined at runtime; for example, 16-byte
8595	// atomics have lock-free implementations on some, but not all,
8596	// x86-64 processors.
8597
8598	// Check power-of-two.
8599	CharUnits Size = CharUnits::fromQuantity(SizeVal.getZExtValue());
8600	if (Size.isPowerOfTwo()) {
8601	// Check against inlining width.
8602	unsigned InlineWidthBits =
8603	Info.Ctx.getTargetInfo().getMaxAtomicInlineWidth();
8604	if (Size <= Info.Ctx.toCharUnitsFromBits(InlineWidthBits)) {
8605	if (BuiltinOp == Builtin::BI__c11_atomic_is_lock_free \|\|
8606	Size == CharUnits::One() \|\|
8607	E->getArg(1)->isNullPointerConstant(Info.Ctx,
8608	Expr::NPC_NeverValueDependent))
8609	// OK, we will inline appropriately-aligned operations of this size,
8610	// and _Atomic(T) is appropriately-aligned.
8611	return Success(1, E);
8612
8613	QualType PointeeType = E->getArg(1)->IgnoreImpCasts()->getType()->
8614	castAs<PointerType>()->getPointeeType();
8615	if (!PointeeType->isIncompleteType() &&
8616	Info.Ctx.getTypeAlignInChars(PointeeType) >= Size) {
8617	// OK, we will inline operations on this object.
8618	return Success(1, E);
8619	}
8620	}
8621	}
8622
8623	return BuiltinOp == Builtin::BI__atomic_always_lock_free ?
8624	Success(0, E) : Error(E);
8625	}
8626	case Builtin::BIomp_is_initial_device:
8627	// We can decide statically which value the runtime would return if called.
8628	return Success(Info.getLangOpts().OpenMPIsDevice ? 0 : 1, E);
8629	case Builtin::BI__builtin_add_overflow:
8630	case Builtin::BI__builtin_sub_overflow:
8631	case Builtin::BI__builtin_mul_overflow:
8632	case Builtin::BI__builtin_sadd_overflow:
8633	case Builtin::BI__builtin_uadd_overflow:
8634	case Builtin::BI__builtin_uaddl_overflow:
8635	case Builtin::BI__builtin_uaddll_overflow:
8636	case Builtin::BI__builtin_usub_overflow:
8637	case Builtin::BI__builtin_usubl_overflow:
8638	case Builtin::BI__builtin_usubll_overflow:
8639	case Builtin::BI__builtin_umul_overflow:
8640	case Builtin::BI__builtin_umull_overflow:
8641	case Builtin::BI__builtin_umulll_overflow:
8642	case Builtin::BI__builtin_saddl_overflow:
8643	case Builtin::BI__builtin_saddll_overflow:
8644	case Builtin::BI__builtin_ssub_overflow:
8645	case Builtin::BI__builtin_ssubl_overflow:
8646	case Builtin::BI__builtin_ssubll_overflow:
8647	case Builtin::BI__builtin_smul_overflow:
8648	case Builtin::BI__builtin_smull_overflow:
8649	case Builtin::BI__builtin_smulll_overflow: {
8650	LValue ResultLValue;
8651	APSInt LHS, RHS;
8652
8653	QualType ResultType = E->getArg(2)->getType()->getPointeeType();
8654	if (!EvaluateInteger(E->getArg(0), LHS, Info) \|\|
8655	!EvaluateInteger(E->getArg(1), RHS, Info) \|\|
8656	!EvaluatePointer(E->getArg(2), ResultLValue, Info))
8657	return false;
8658
8659	APSInt Result;
8660	bool DidOverflow = false;
8661
8662	// If the types don't have to match, enlarge all 3 to the largest of them.
8663	if (BuiltinOp == Builtin::BI__builtin_add_overflow \|\|
8664	BuiltinOp == Builtin::BI__builtin_sub_overflow \|\|
8665	BuiltinOp == Builtin::BI__builtin_mul_overflow) {
8666	bool IsSigned = LHS.isSigned() \|\| RHS.isSigned() \|\|
8667	ResultType->isSignedIntegerOrEnumerationType();
8668	bool AllSigned = LHS.isSigned() && RHS.isSigned() &&
8669	ResultType->isSignedIntegerOrEnumerationType();
8670	uint64_t LHSSize = LHS.getBitWidth();
8671	uint64_t RHSSize = RHS.getBitWidth();
8672	uint64_t ResultSize = Info.Ctx.getTypeSize(ResultType);
8673	uint64_t MaxBits = std::max(std::max(LHSSize, RHSSize), ResultSize);
8674
8675	// Add an additional bit if the signedness isn't uniformly agreed to. We
8676	// could do this ONLY if there is a signed and an unsigned that both have
8677	// MaxBits, but the code to check that is pretty nasty. The issue will be
8678	// caught in the shrink-to-result later anyway.
8679	if (IsSigned && !AllSigned)
8680	++MaxBits;
8681
8682	LHS = APSInt(IsSigned ? LHS.sextOrSelf(MaxBits) : LHS.zextOrSelf(MaxBits),
8683	!IsSigned);
8684	RHS = APSInt(IsSigned ? RHS.sextOrSelf(MaxBits) : RHS.zextOrSelf(MaxBits),
8685	!IsSigned);
8686	Result = APSInt(MaxBits, !IsSigned);
8687	}
8688
8689	// Find largest int.
8690	switch (BuiltinOp) {
8691	default:
8692	llvm_unreachable("Invalid value for BuiltinOp");
8693	case Builtin::BI__builtin_add_overflow:
8694	case Builtin::BI__builtin_sadd_overflow:
8695	case Builtin::BI__builtin_saddl_overflow:
8696	case Builtin::BI__builtin_saddll_overflow:
8697	case Builtin::BI__builtin_uadd_overflow:
8698	case Builtin::BI__builtin_uaddl_overflow:
8699	case Builtin::BI__builtin_uaddll_overflow:
8700	Result = LHS.isSigned() ? LHS.sadd_ov(RHS, DidOverflow)
8701	: LHS.uadd_ov(RHS, DidOverflow);
8702	break;
8703	case Builtin::BI__builtin_sub_overflow:
8704	case Builtin::BI__builtin_ssub_overflow:
8705	case Builtin::BI__builtin_ssubl_overflow:
8706	case Builtin::BI__builtin_ssubll_overflow:
8707	case Builtin::BI__builtin_usub_overflow:
8708	case Builtin::BI__builtin_usubl_overflow:
8709	case Builtin::BI__builtin_usubll_overflow:
8710	Result = LHS.isSigned() ? LHS.ssub_ov(RHS, DidOverflow)
8711	: LHS.usub_ov(RHS, DidOverflow);
8712	break;
8713	case Builtin::BI__builtin_mul_overflow:
8714	case Builtin::BI__builtin_smul_overflow:
8715	case Builtin::BI__builtin_smull_overflow:
8716	case Builtin::BI__builtin_smulll_overflow:
8717	case Builtin::BI__builtin_umul_overflow:
8718	case Builtin::BI__builtin_umull_overflow:
8719	case Builtin::BI__builtin_umulll_overflow:
8720	Result = LHS.isSigned() ? LHS.smul_ov(RHS, DidOverflow)
8721	: LHS.umul_ov(RHS, DidOverflow);
8722	break;
8723	}
8724
8725	// In the case where multiple sizes are allowed, truncate and see if
8726	// the values are the same.
8727	if (BuiltinOp == Builtin::BI__builtin_add_overflow \|\|
8728	BuiltinOp == Builtin::BI__builtin_sub_overflow \|\|
8729	BuiltinOp == Builtin::BI__builtin_mul_overflow) {
8730	// APSInt doesn't have a TruncOrSelf, so we use extOrTrunc instead,
8731	// since it will give us the behavior of a TruncOrSelf in the case where
8732	// its parameter <= its size. We previously set Result to be at least the
8733	// type-size of the result, so getTypeSize(ResultType) <= Result.BitWidth
8734	// will work exactly like TruncOrSelf.
8735	APSInt Temp = Result.extOrTrunc(Info.Ctx.getTypeSize(ResultType));
8736	Temp.setIsSigned(ResultType->isSignedIntegerOrEnumerationType());
8737
8738	if (!APSInt::isSameValue(Temp, Result))
8739	DidOverflow = true;
8740	Result = Temp;
8741	}
8742
8743	APValue APV{Result};
8744	if (!handleAssignment(Info, E, ResultLValue, ResultType, APV))
8745	return false;
8746	return Success(DidOverflow, E);
8747	}
8748	}
8749	}
8750
8751	/// Determine whether this is a pointer past the end of the complete
8752	/// object referred to by the lvalue.
8753	static bool isOnePastTheEndOfCompleteObject(const ASTContext &Ctx,
8754	const LValue &LV) {
8755	// A null pointer can be viewed as being "past the end" but we don't
8756	// choose to look at it that way here.
8757	if (!LV.getLValueBase())
8758	return false;
8759
8760	// If the designator is valid and refers to a subobject, we're not pointing
8761	// past the end.
8762	if (!LV.getLValueDesignator().Invalid &&
8763	!LV.getLValueDesignator().isOnePastTheEnd())
8764	return false;
8765
8766	// A pointer to an incomplete type might be past-the-end if the type's size is
8767	// zero. We cannot tell because the type is incomplete.
8768	QualType Ty = getType(LV.getLValueBase());
8769	if (Ty->isIncompleteType())
8770	return true;
8771
8772	// We're a past-the-end pointer if we point to the byte after the object,
8773	// no matter what our type or path is.
8774	auto Size = Ctx.getTypeSizeInChars(Ty);
8775	return LV.getLValueOffset() == Size;
8776	}
8777
8778	namespace {
8779
8780	/// Data recursive integer evaluator of certain binary operators.
8781	///
8782	/// We use a data recursive algorithm for binary operators so that we are able
8783	/// to handle extreme cases of chained binary operators without causing stack
8784	/// overflow.
8785	class DataRecursiveIntBinOpEvaluator {
8786	struct EvalResult {
8787	APValue Val;
8788	bool Failed;
8789
8790	EvalResult() : Failed(false) { }
8791
8792	void swap(EvalResult &RHS) {
8793	Val.swap(RHS.Val);
8794	Failed = RHS.Failed;
8795	RHS.Failed = false;
8796	}
8797	};
8798
8799	struct Job {
8800	const Expr *E;
8801	EvalResult LHSResult; // meaningful only for binary operator expression.
8802	enum { AnyExprKind, BinOpKind, BinOpVisitedLHSKind } Kind;
8803
8804	Job() = default;
8805	Job(Job &&) = default;
8806
8807	void startSpeculativeEval(EvalInfo &Info) {
8808	SpecEvalRAII = SpeculativeEvaluationRAII(Info);
8809	}
8810
8811	private:
8812	SpeculativeEvaluationRAII SpecEvalRAII;
8813	};
8814
8815	SmallVector<Job, 16> Queue;
8816
8817	IntExprEvaluator &IntEval;
8818	EvalInfo &Info;
8819	APValue &FinalResult;
8820
8821	public:
8822	DataRecursiveIntBinOpEvaluator(IntExprEvaluator &IntEval, APValue &Result)
8823	: IntEval(IntEval), Info(IntEval.getEvalInfo()), FinalResult(Result) { }
8824
8825	/// True if \param E is a binary operator that we are going to handle
8826	/// data recursively.
8827	/// We handle binary operators that are comma, logical, or that have operands
8828	/// with integral or enumeration type.
8829	static bool shouldEnqueue(const BinaryOperator *E) {
8830	return E->getOpcode() == BO_Comma \|\| E->isLogicalOp() \|\|
8831	(E->isRValue() && E->getType()->isIntegralOrEnumerationType() &&
8832	E->getLHS()->getType()->isIntegralOrEnumerationType() &&
8833	E->getRHS()->getType()->isIntegralOrEnumerationType());
8834	}
8835
8836	bool Traverse(const BinaryOperator *E) {
8837	enqueue(E);
8838	EvalResult PrevResult;
8839	while (!Queue.empty())
8840	process(PrevResult);
8841
8842	if (PrevResult.Failed) return false;
8843
8844	FinalResult.swap(PrevResult.Val);
8845	return true;
8846	}
8847
8848	private:
8849	bool Success(uint64_t Value, const Expr *E, APValue &Result) {
8850	return IntEval.Success(Value, E, Result);
8851	}
8852	bool Success(const APSInt &Value, const Expr *E, APValue &Result) {
8853	return IntEval.Success(Value, E, Result);
8854	}
8855	bool Error(const Expr *E) {
8856	return IntEval.Error(E);
8857	}
8858	bool Error(const Expr *E, diag::kind D) {
8859	return IntEval.Error(E, D);
8860	}
8861
8862	OptionalDiagnostic CCEDiag(const Expr *E, diag::kind D) {
8863	return Info.CCEDiag(E, D);
8864	}
8865
8866	// Returns true if visiting the RHS is necessary, false otherwise.
8867	bool VisitBinOpLHSOnly(EvalResult &LHSResult, const BinaryOperator *E,
8868	bool &SuppressRHSDiags);
8869
8870	bool VisitBinOp(const EvalResult &LHSResult, const EvalResult &RHSResult,
8871	const BinaryOperator *E, APValue &Result);
8872
8873	void EvaluateExpr(const Expr *E, EvalResult &Result) {
8874	Result.Failed = !Evaluate(Result.Val, Info, E);
8875	if (Result.Failed)
8876	Result.Val = APValue();
8877	}
8878
8879	void process(EvalResult &Result);
8880
8881	void enqueue(const Expr *E) {
8882	E = E->IgnoreParens();
8883	Queue.resize(Queue.size()+1);
8884	Queue.back().E = E;
8885	Queue.back().Kind = Job::AnyExprKind;
8886	}
8887	};
8888
8889	}
8890
8891	bool DataRecursiveIntBinOpEvaluator::
8892	VisitBinOpLHSOnly(EvalResult &LHSResult, const BinaryOperator *E,
8893	bool &SuppressRHSDiags) {
8894	if (E->getOpcode() == BO_Comma) {
8895	// Ignore LHS but note if we could not evaluate it.
8896	if (LHSResult.Failed)
8897	return Info.noteSideEffect();
8898	return true;
8899	}
8900
8901	if (E->isLogicalOp()) {
8902	bool LHSAsBool;
8903	if (!LHSResult.Failed && HandleConversionToBool(LHSResult.Val, LHSAsBool)) {
8904	// We were able to evaluate the LHS, see if we can get away with not
8905	// evaluating the RHS: 0 && X -> 0, 1 \|\| X -> 1
8906	if (LHSAsBool == (E->getOpcode() == BO_LOr)) {
8907	Success(LHSAsBool, E, LHSResult.Val);
8908	return false; // Ignore RHS
8909	}
8910	} else {
8911	LHSResult.Failed = true;
8912
8913	// Since we weren't able to evaluate the left hand side, it
8914	// might have had side effects.
8915	if (!Info.noteSideEffect())
8916	return false;
8917
8918	// We can't evaluate the LHS; however, sometimes the result
8919	// is determined by the RHS: X && 0 -> 0, X \|\| 1 -> 1.
8920	// Don't ignore RHS and suppress diagnostics from this arm.
8921	SuppressRHSDiags = true;
8922	}
8923
8924	return true;
8925	}
8926
8927	getLHS()->getType()->isIntegralOrEnumerationType() && E->getRHS()->getType()->isIntegralOrEnumerationType()", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 8928, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(E->getLHS()->getType()->isIntegralOrEnumerationType() &&
8928	getLHS()->getType()->isIntegralOrEnumerationType() && E->getRHS()->getType()->isIntegralOrEnumerationType()", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 8928, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true"> E->getRHS()->getType()->isIntegralOrEnumerationType());
8929
8930	if (LHSResult.Failed && !Info.noteFailure())
8931	return false; // Ignore RHS;
8932
8933	return true;
8934	}
8935
8936	static void addOrSubLValueAsInteger(APValue &LVal, const APSInt &Index,
8937	bool IsSub) {
8938	// Compute the new offset in the appropriate width, wrapping at 64 bits.
8939	// FIXME: When compiling for a 32-bit target, we should use 32-bit
8940	// offsets.
8941	(0) . __assert_fail ("!LVal.hasLValuePath() && \"have designator for integer lvalue\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 8941, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(!LVal.hasLValuePath() && "have designator for integer lvalue");
8942	CharUnits &Offset = LVal.getLValueOffset();
8943	uint64_t Offset64 = Offset.getQuantity();
8944	uint64_t Index64 = Index.extOrTrunc(64).getZExtValue();
8945	Offset = CharUnits::fromQuantity(IsSub ? Offset64 - Index64
8946	: Offset64 + Index64);
8947	}
8948
8949	bool DataRecursiveIntBinOpEvaluator::
8950	VisitBinOp(const EvalResult &LHSResult, const EvalResult &RHSResult,
8951	const BinaryOperator *E, APValue &Result) {
8952	if (E->getOpcode() == BO_Comma) {
8953	if (RHSResult.Failed)
8954	return false;
8955	Result = RHSResult.Val;
8956	return true;
8957	}
8958
8959	if (E->isLogicalOp()) {
8960	bool lhsResult, rhsResult;
8961	bool LHSIsOK = HandleConversionToBool(LHSResult.Val, lhsResult);
8962	bool RHSIsOK = HandleConversionToBool(RHSResult.Val, rhsResult);
8963
8964	if (LHSIsOK) {
8965	if (RHSIsOK) {
8966	if (E->getOpcode() == BO_LOr)
8967	return Success(lhsResult \|\| rhsResult, E, Result);
8968	else
8969	return Success(lhsResult && rhsResult, E, Result);
8970	}
8971	} else {
8972	if (RHSIsOK) {
8973	// We can't evaluate the LHS; however, sometimes the result
8974	// is determined by the RHS: X && 0 -> 0, X \|\| 1 -> 1.
8975	if (rhsResult == (E->getOpcode() == BO_LOr))
8976	return Success(rhsResult, E, Result);
8977	}
8978	}
8979
8980	return false;
8981	}
8982
8983	getLHS()->getType()->isIntegralOrEnumerationType() && E->getRHS()->getType()->isIntegralOrEnumerationType()", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 8984, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(E->getLHS()->getType()->isIntegralOrEnumerationType() &&
8984	getLHS()->getType()->isIntegralOrEnumerationType() && E->getRHS()->getType()->isIntegralOrEnumerationType()", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 8984, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true"> E->getRHS()->getType()->isIntegralOrEnumerationType());
8985
8986	if (LHSResult.Failed \|\| RHSResult.Failed)
8987	return false;
8988
8989	const APValue &LHSVal = LHSResult.Val;
8990	const APValue &RHSVal = RHSResult.Val;
8991
8992	// Handle cases like (unsigned long)&a + 4.
8993	if (E->isAdditiveOp() && LHSVal.isLValue() && RHSVal.isInt()) {
8994	Result = LHSVal;
8995	addOrSubLValueAsInteger(Result, RHSVal.getInt(), E->getOpcode() == BO_Sub);
8996	return true;
8997	}
8998
8999	// Handle cases like 4 + (unsigned long)&a
9000	if (E->getOpcode() == BO_Add &&
9001	RHSVal.isLValue() && LHSVal.isInt()) {
9002	Result = RHSVal;
9003	addOrSubLValueAsInteger(Result, LHSVal.getInt(), /IsSub/false);
9004	return true;
9005	}
9006
9007	if (E->getOpcode() == BO_Sub && LHSVal.isLValue() && RHSVal.isLValue()) {
9008	// Handle (intptr_t)&&A - (intptr_t)&&B.
9009	if (!LHSVal.getLValueOffset().isZero() \|\|
9010	!RHSVal.getLValueOffset().isZero())
9011	return false;
9012	const Expr LHSExpr = LHSVal.getLValueBase().dyn_cast<const Expr>();
9013	const Expr RHSExpr = RHSVal.getLValueBase().dyn_cast<const Expr>();
9014	if (!LHSExpr \|\| !RHSExpr)
9015	return false;
9016	const AddrLabelExpr *LHSAddrExpr = dyn_cast<AddrLabelExpr>(LHSExpr);
9017	const AddrLabelExpr *RHSAddrExpr = dyn_cast<AddrLabelExpr>(RHSExpr);
9018	if (!LHSAddrExpr \|\| !RHSAddrExpr)
9019	return false;
9020	// Make sure both labels come from the same function.
9021	if (LHSAddrExpr->getLabel()->getDeclContext() !=
9022	RHSAddrExpr->getLabel()->getDeclContext())
9023	return false;
9024	Result = APValue(LHSAddrExpr, RHSAddrExpr);
9025	return true;
9026	}
9027
9028	// All the remaining cases expect both operands to be an integer
9029	if (!LHSVal.isInt() \|\| !RHSVal.isInt())
9030	return Error(E);
9031
9032	// Set up the width and signedness manually, in case it can't be deduced
9033	// from the operation we're performing.
9034	// FIXME: Don't do this in the cases where we can deduce it.
9035	APSInt Value(Info.Ctx.getIntWidth(E->getType()),
9036	E->getType()->isUnsignedIntegerOrEnumerationType());
9037	if (!handleIntIntBinOp(Info, E, LHSVal.getInt(), E->getOpcode(),
9038	RHSVal.getInt(), Value))
9039	return false;
9040	return Success(Value, E, Result);
9041	}
9042
9043	void DataRecursiveIntBinOpEvaluator::process(EvalResult &Result) {
9044	Job &job = Queue.back();
9045
9046	switch (job.Kind) {
9047	case Job::AnyExprKind: {
9048	if (const BinaryOperator *Bop = dyn_cast<BinaryOperator>(job.E)) {
9049	if (shouldEnqueue(Bop)) {
9050	job.Kind = Job::BinOpKind;
9051	enqueue(Bop->getLHS());
9052	return;
9053	}
9054	}
9055
9056	EvaluateExpr(job.E, Result);
9057	Queue.pop_back();
9058	return;
9059	}
9060
9061	case Job::BinOpKind: {
9062	const BinaryOperator *Bop = cast<BinaryOperator>(job.E);
9063	bool SuppressRHSDiags = false;
9064	if (!VisitBinOpLHSOnly(Result, Bop, SuppressRHSDiags)) {
9065	Queue.pop_back();
9066	return;
9067	}
9068	if (SuppressRHSDiags)
9069	job.startSpeculativeEval(Info);
9070	job.LHSResult.swap(Result);
9071	job.Kind = Job::BinOpVisitedLHSKind;
9072	enqueue(Bop->getRHS());
9073	return;
9074	}
9075
9076	case Job::BinOpVisitedLHSKind: {
9077	const BinaryOperator *Bop = cast<BinaryOperator>(job.E);
9078	EvalResult RHS;
9079	RHS.swap(Result);
9080	Result.Failed = !VisitBinOp(job.LHSResult, RHS, Bop, Result.Val);
9081	Queue.pop_back();
9082	return;
9083	}
9084	}
9085
9086	llvm_unreachable("Invalid Job::Kind!");
9087	}
9088
9089	namespace {
9090	/// Used when we determine that we should fail, but can keep evaluating prior to
9091	/// noting that we had a failure.
9092	class DelayedNoteFailureRAII {
9093	EvalInfo &Info;
9094	bool NoteFailure;
9095
9096	public:
9097	DelayedNoteFailureRAII(EvalInfo &Info, bool NoteFailure = true)
9098	: Info(Info), NoteFailure(NoteFailure) {}
9099	~DelayedNoteFailureRAII() {
9100	if (NoteFailure) {
9101	bool ContinueAfterFailure = Info.noteFailure();
9102	(void)ContinueAfterFailure;
9103	(0) . __assert_fail ("ContinueAfterFailure && \"Shouldn't have kept evaluating on failure.\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 9104, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(ContinueAfterFailure &&
9104	(0) . __assert_fail ("ContinueAfterFailure && \"Shouldn't have kept evaluating on failure.\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 9104, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true"> "Shouldn't have kept evaluating on failure.");
9105	}
9106	}
9107	};
9108	}
9109
9110	template <class SuccessCB, class AfterCB>
9111	static bool
9112	EvaluateComparisonBinaryOperator(EvalInfo &Info, const BinaryOperator *E,
9113	SuccessCB &&Success, AfterCB &&DoAfter) {
9114	(0) . __assert_fail ("E->isComparisonOp() && \"expected comparison operator\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 9114, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(E->isComparisonOp() && "expected comparison operator");
9115	(0) . __assert_fail ("(E->getOpcode() == BO_Cmp \|\| E->getType()->isIntegralOrEnumerationType()) && \"unsupported binary expression evaluation\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 9117, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert((E->getOpcode() == BO_Cmp \|\|
9116	(0) . __assert_fail ("(E->getOpcode() == BO_Cmp \|\| E->getType()->isIntegralOrEnumerationType()) && \"unsupported binary expression evaluation\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 9117, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true"> E->getType()->isIntegralOrEnumerationType()) &&
9117	(0) . __assert_fail ("(E->getOpcode() == BO_Cmp \|\| E->getType()->isIntegralOrEnumerationType()) && \"unsupported binary expression evaluation\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 9117, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true"> "unsupported binary expression evaluation");
9118	auto Error = [&](const Expr *E) {
9119	Info.FFDiag(E, diag::note_invalid_subexpr_in_const_expr);
9120	return false;
9121	};
9122
9123	using CCR = ComparisonCategoryResult;
9124	bool IsRelational = E->isRelationalOp();
9125	bool IsEquality = E->isEqualityOp();
9126	if (E->getOpcode() == BO_Cmp) {
9127	const ComparisonCategoryInfo &CmpInfo =
9128	Info.Ctx.CompCategories.getInfoForType(E->getType());
9129	IsRelational = CmpInfo.isOrdered();
9130	IsEquality = CmpInfo.isEquality();
9131	}
9132
9133	QualType LHSTy = E->getLHS()->getType();
9134	QualType RHSTy = E->getRHS()->getType();
9135
9136	if (LHSTy->isIntegralOrEnumerationType() &&
9137	RHSTy->isIntegralOrEnumerationType()) {
9138	APSInt LHS, RHS;
9139	bool LHSOK = EvaluateInteger(E->getLHS(), LHS, Info);
9140	if (!LHSOK && !Info.noteFailure())
9141	return false;
9142	if (!EvaluateInteger(E->getRHS(), RHS, Info) \|\| !LHSOK)
9143	return false;
9144	if (LHS < RHS)
9145	return Success(CCR::Less, E);
9146	if (LHS > RHS)
9147	return Success(CCR::Greater, E);
9148	return Success(CCR::Equal, E);
9149	}
9150
9151	if (LHSTy->isFixedPointType() \|\| RHSTy->isFixedPointType()) {
9152	APFixedPoint LHSFX(Info.Ctx.getFixedPointSemantics(LHSTy));
9153	APFixedPoint RHSFX(Info.Ctx.getFixedPointSemantics(RHSTy));
9154
9155	bool LHSOK = EvaluateFixedPointOrInteger(E->getLHS(), LHSFX, Info);
9156	if (!LHSOK && !Info.noteFailure())
9157	return false;
9158	if (!EvaluateFixedPointOrInteger(E->getRHS(), RHSFX, Info) \|\| !LHSOK)
9159	return false;
9160	if (LHSFX < RHSFX)
9161	return Success(CCR::Less, E);
9162	if (LHSFX > RHSFX)
9163	return Success(CCR::Greater, E);
9164	return Success(CCR::Equal, E);
9165	}
9166
9167	if (LHSTy->isAnyComplexType() \|\| RHSTy->isAnyComplexType()) {
9168	ComplexValue LHS, RHS;
9169	bool LHSOK;
9170	if (E->isAssignmentOp()) {
9171	LValue LV;
9172	EvaluateLValue(E->getLHS(), LV, Info);
9173	LHSOK = false;
9174	} else if (LHSTy->isRealFloatingType()) {
9175	LHSOK = EvaluateFloat(E->getLHS(), LHS.FloatReal, Info);
9176	if (LHSOK) {
9177	LHS.makeComplexFloat();
9178	LHS.FloatImag = APFloat(LHS.FloatReal.getSemantics());
9179	}
9180	} else {
9181	LHSOK = EvaluateComplex(E->getLHS(), LHS, Info);
9182	}
9183	if (!LHSOK && !Info.noteFailure())
9184	return false;
9185
9186	if (E->getRHS()->getType()->isRealFloatingType()) {
9187	if (!EvaluateFloat(E->getRHS(), RHS.FloatReal, Info) \|\| !LHSOK)
9188	return false;
9189	RHS.makeComplexFloat();
9190	RHS.FloatImag = APFloat(RHS.FloatReal.getSemantics());
9191	} else if (!EvaluateComplex(E->getRHS(), RHS, Info) \|\| !LHSOK)
9192	return false;
9193
9194	if (LHS.isComplexFloat()) {
9195	APFloat::cmpResult CR_r =
9196	LHS.getComplexFloatReal().compare(RHS.getComplexFloatReal());
9197	APFloat::cmpResult CR_i =
9198	LHS.getComplexFloatImag().compare(RHS.getComplexFloatImag());
9199	bool IsEqual = CR_r == APFloat::cmpEqual && CR_i == APFloat::cmpEqual;
9200	return Success(IsEqual ? CCR::Equal : CCR::Nonequal, E);
9201	} else {
9202	(0) . __assert_fail ("IsEquality && \"invalid complex comparison\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 9202, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(IsEquality && "invalid complex comparison");
9203	bool IsEqual = LHS.getComplexIntReal() == RHS.getComplexIntReal() &&
9204	LHS.getComplexIntImag() == RHS.getComplexIntImag();
9205	return Success(IsEqual ? CCR::Equal : CCR::Nonequal, E);
9206	}
9207	}
9208
9209	if (LHSTy->isRealFloatingType() &&
9210	RHSTy->isRealFloatingType()) {
9211	APFloat RHS(0.0), LHS(0.0);
9212
9213	bool LHSOK = EvaluateFloat(E->getRHS(), RHS, Info);
9214	if (!LHSOK && !Info.noteFailure())
9215	return false;
9216
9217	if (!EvaluateFloat(E->getLHS(), LHS, Info) \|\| !LHSOK)
9218	return false;
9219
9220	(0) . __assert_fail ("E->isComparisonOp() && \"Invalid binary operator!\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 9220, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(E->isComparisonOp() && "Invalid binary operator!");
9221	auto GetCmpRes = [&]() {
9222	switch (LHS.compare(RHS)) {
9223	case APFloat::cmpEqual:
9224	return CCR::Equal;
9225	case APFloat::cmpLessThan:
9226	return CCR::Less;
9227	case APFloat::cmpGreaterThan:
9228	return CCR::Greater;
9229	case APFloat::cmpUnordered:
9230	return CCR::Unordered;
9231	}
9232	llvm_unreachable("Unrecognised APFloat::cmpResult enum");
9233	};
9234	return Success(GetCmpRes(), E);
9235	}
9236
9237	if (LHSTy->isPointerType() && RHSTy->isPointerType()) {
9238	LValue LHSValue, RHSValue;
9239
9240	bool LHSOK = EvaluatePointer(E->getLHS(), LHSValue, Info);
9241	if (!LHSOK && !Info.noteFailure())
9242	return false;
9243
9244	if (!EvaluatePointer(E->getRHS(), RHSValue, Info) \|\| !LHSOK)
9245	return false;
9246
9247	// Reject differing bases from the normal codepath; we special-case
9248	// comparisons to null.
9249	if (!HasSameBase(LHSValue, RHSValue)) {
9250	// Inequalities and subtractions between unrelated pointers have
9251	// unspecified or undefined behavior.
9252	if (!IsEquality)
9253	return Error(E);
9254	// A constant address may compare equal to the address of a symbol.
9255	// The one exception is that address of an object cannot compare equal
9256	// to a null pointer constant.
9257	if ((!LHSValue.Base && !LHSValue.Offset.isZero()) \|\|
9258	(!RHSValue.Base && !RHSValue.Offset.isZero()))
9259	return Error(E);
9260	// It's implementation-defined whether distinct literals will have
9261	// distinct addresses. In clang, the result of such a comparison is
9262	// unspecified, so it is not a constant expression. However, we do know
9263	// that the address of a literal will be non-null.
9264	if ((IsLiteralLValue(LHSValue) \|\| IsLiteralLValue(RHSValue)) &&
9265	LHSValue.Base && RHSValue.Base)
9266	return Error(E);
9267	// We can't tell whether weak symbols will end up pointing to the same
9268	// object.
9269	if (IsWeakLValue(LHSValue) \|\| IsWeakLValue(RHSValue))
9270	return Error(E);
9271	// We can't compare the address of the start of one object with the
9272	// past-the-end address of another object, per C++ DR1652.
9273	if ((LHSValue.Base && LHSValue.Offset.isZero() &&
9274	isOnePastTheEndOfCompleteObject(Info.Ctx, RHSValue)) \|\|
9275	(RHSValue.Base && RHSValue.Offset.isZero() &&
9276	isOnePastTheEndOfCompleteObject(Info.Ctx, LHSValue)))
9277	return Error(E);
9278	// We can't tell whether an object is at the same address as another
9279	// zero sized object.
9280	if ((RHSValue.Base && isZeroSized(LHSValue)) \|\|
9281	(LHSValue.Base && isZeroSized(RHSValue)))
9282	return Error(E);
9283	return Success(CCR::Nonequal, E);
9284	}
9285
9286	const CharUnits &LHSOffset = LHSValue.getLValueOffset();
9287	const CharUnits &RHSOffset = RHSValue.getLValueOffset();
9288
9289	SubobjectDesignator &LHSDesignator = LHSValue.getLValueDesignator();
9290	SubobjectDesignator &RHSDesignator = RHSValue.getLValueDesignator();
9291
9292	// C++11 [expr.rel]p3:
9293	// Pointers to void (after pointer conversions) can be compared, with a
9294	// result defined as follows: If both pointers represent the same
9295	// address or are both the null pointer value, the result is true if the
9296	// operator is <= or >= and false otherwise; otherwise the result is
9297	// unspecified.
9298	// We interpret this as applying to pointers to cv void.
9299	if (LHSTy->isVoidPointerType() && LHSOffset != RHSOffset && IsRelational)
9300	Info.CCEDiag(E, diag::note_constexpr_void_comparison);
9301
9302	// C++11 [expr.rel]p2:
9303	// - If two pointers point to non-static data members of the same object,
9304	// or to subobjects or array elements fo such members, recursively, the
9305	// pointer to the later declared member compares greater provided the
9306	// two members have the same access control and provided their class is
9307	// not a union.
9308	// [...]
9309	// - Otherwise pointer comparisons are unspecified.
9310	if (!LHSDesignator.Invalid && !RHSDesignator.Invalid && IsRelational) {
9311	bool WasArrayIndex;
9312	unsigned Mismatch = FindDesignatorMismatch(
9313	getType(LHSValue.Base), LHSDesignator, RHSDesignator, WasArrayIndex);
9314	// At the point where the designators diverge, the comparison has a
9315	// specified value if:
9316	// - we are comparing array indices
9317	// - we are comparing fields of a union, or fields with the same access
9318	// Otherwise, the result is unspecified and thus the comparison is not a
9319	// constant expression.
9320	if (!WasArrayIndex && Mismatch < LHSDesignator.Entries.size() &&
9321	Mismatch < RHSDesignator.Entries.size()) {
9322	const FieldDecl *LF = getAsField(LHSDesignator.Entries[Mismatch]);
9323	const FieldDecl *RF = getAsField(RHSDesignator.Entries[Mismatch]);
9324	if (!LF && !RF)
9325	Info.CCEDiag(E, diag::note_constexpr_pointer_comparison_base_classes);
9326	else if (!LF)
9327	Info.CCEDiag(E, diag::note_constexpr_pointer_comparison_base_field)
9328	<< getAsBaseClass(LHSDesignator.Entries[Mismatch])
9329	<< RF->getParent() << RF;
9330	else if (!RF)
9331	Info.CCEDiag(E, diag::note_constexpr_pointer_comparison_base_field)
9332	<< getAsBaseClass(RHSDesignator.Entries[Mismatch])
9333	<< LF->getParent() << LF;
9334	else if (!LF->getParent()->isUnion() &&
9335	LF->getAccess() != RF->getAccess())
9336	Info.CCEDiag(E,
9337	diag::note_constexpr_pointer_comparison_differing_access)
9338	<< LF << LF->getAccess() << RF << RF->getAccess()
9339	<< LF->getParent();
9340	}
9341	}
9342
9343	// The comparison here must be unsigned, and performed with the same
9344	// width as the pointer.
9345	unsigned PtrSize = Info.Ctx.getTypeSize(LHSTy);
9346	uint64_t CompareLHS = LHSOffset.getQuantity();
9347	uint64_t CompareRHS = RHSOffset.getQuantity();
9348	(0) . __assert_fail ("PtrSize <= 64 && \"Unexpected pointer width\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 9348, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(PtrSize <= 64 && "Unexpected pointer width");
9349	uint64_t Mask = ~0ULL >> (64 - PtrSize);
9350	CompareLHS &= Mask;
9351	CompareRHS &= Mask;
9352
9353	// If there is a base and this is a relational operator, we can only
9354	// compare pointers within the object in question; otherwise, the result
9355	// depends on where the object is located in memory.
9356	if (!LHSValue.Base.isNull() && IsRelational) {
9357	QualType BaseTy = getType(LHSValue.Base);
9358	if (BaseTy->isIncompleteType())
9359	return Error(E);
9360	CharUnits Size = Info.Ctx.getTypeSizeInChars(BaseTy);
9361	uint64_t OffsetLimit = Size.getQuantity();
9362	if (CompareLHS > OffsetLimit \|\| CompareRHS > OffsetLimit)
9363	return Error(E);
9364	}
9365
9366	if (CompareLHS < CompareRHS)
9367	return Success(CCR::Less, E);
9368	if (CompareLHS > CompareRHS)
9369	return Success(CCR::Greater, E);
9370	return Success(CCR::Equal, E);
9371	}
9372
9373	if (LHSTy->isMemberPointerType()) {
9374	(0) . __assert_fail ("IsEquality && \"unexpected member pointer operation\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 9374, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(IsEquality && "unexpected member pointer operation");
9375	(0) . __assert_fail ("RHSTy->isMemberPointerType() && \"invalid comparison\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 9375, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(RHSTy->isMemberPointerType() && "invalid comparison");
9376
9377	MemberPtr LHSValue, RHSValue;
9378
9379	bool LHSOK = EvaluateMemberPointer(E->getLHS(), LHSValue, Info);
9380	if (!LHSOK && !Info.noteFailure())
9381	return false;
9382
9383	if (!EvaluateMemberPointer(E->getRHS(), RHSValue, Info) \|\| !LHSOK)
9384	return false;
9385
9386	// C++11 [expr.eq]p2:
9387	// If both operands are null, they compare equal. Otherwise if only one is
9388	// null, they compare unequal.
9389	if (!LHSValue.getDecl() \|\| !RHSValue.getDecl()) {
9390	bool Equal = !LHSValue.getDecl() && !RHSValue.getDecl();
9391	return Success(Equal ? CCR::Equal : CCR::Nonequal, E);
9392	}
9393
9394	// Otherwise if either is a pointer to a virtual member function, the
9395	// result is unspecified.
9396	if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(LHSValue.getDecl()))
9397	if (MD->isVirtual())
9398	Info.CCEDiag(E, diag::note_constexpr_compare_virtual_mem_ptr) << MD;
9399	if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(RHSValue.getDecl()))
9400	if (MD->isVirtual())
9401	Info.CCEDiag(E, diag::note_constexpr_compare_virtual_mem_ptr) << MD;
9402
9403	// Otherwise they compare equal if and only if they would refer to the
9404	// same member of the same most derived object or the same subobject if
9405	// they were dereferenced with a hypothetical object of the associated
9406	// class type.
9407	bool Equal = LHSValue == RHSValue;
9408	return Success(Equal ? CCR::Equal : CCR::Nonequal, E);
9409	}
9410
9411	if (LHSTy->isNullPtrType()) {
9412	(0) . __assert_fail ("E->isComparisonOp() && \"unexpected nullptr operation\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 9412, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(E->isComparisonOp() && "unexpected nullptr operation");
9413	(0) . __assert_fail ("RHSTy->isNullPtrType() && \"missing pointer conversion\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 9413, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(RHSTy->isNullPtrType() && "missing pointer conversion");
9414	// C++11 [expr.rel]p4, [expr.eq]p3: If two operands of type std::nullptr_t
9415	// are compared, the result is true of the operator is <=, >= or ==, and
9416	// false otherwise.
9417	return Success(CCR::Equal, E);
9418	}
9419
9420	return DoAfter();
9421	}
9422
9423	bool RecordExprEvaluator::VisitBinCmp(const BinaryOperator *E) {
9424	if (!CheckLiteralType(Info, E))
9425	return false;
9426
9427	auto OnSuccess = [&](ComparisonCategoryResult ResKind,
9428	const BinaryOperator *E) {
9429	// Evaluation succeeded. Lookup the information for the comparison category
9430	// type and fetch the VarDecl for the result.
9431	const ComparisonCategoryInfo &CmpInfo =
9432	Info.Ctx.CompCategories.getInfoForType(E->getType());
9433	const VarDecl *VD =
9434	CmpInfo.getValueInfo(CmpInfo.makeWeakResult(ResKind))->VD;
9435	// Check and evaluate the result as a constant expression.
9436	LValue LV;
9437	LV.set(VD);
9438	if (!handleLValueToRValueConversion(Info, E, E->getType(), LV, Result))
9439	return false;
9440	return CheckConstantExpression(Info, E->getExprLoc(), E->getType(), Result);
9441	};
9442	return EvaluateComparisonBinaryOperator(Info, E, OnSuccess, [&]() {
9443	return ExprEvaluatorBaseTy::VisitBinCmp(E);
9444	});
9445	}
9446
9447	bool IntExprEvaluator::VisitBinaryOperator(const BinaryOperator *E) {
9448	// We don't call noteFailure immediately because the assignment happens after
9449	// we evaluate LHS and RHS.
9450	if (!Info.keepEvaluatingAfterFailure() && E->isAssignmentOp())
9451	return Error(E);
9452
9453	DelayedNoteFailureRAII MaybeNoteFailureLater(Info, E->isAssignmentOp());
9454	if (DataRecursiveIntBinOpEvaluator::shouldEnqueue(E))
9455	return DataRecursiveIntBinOpEvaluator(*this, Result).Traverse(E);
9456
9457	(0) . __assert_fail ("(!E->getLHS()->getType()->isIntegralOrEnumerationType() \|\| !E->getRHS()->getType()->isIntegralOrEnumerationType()) && \"DataRecursiveIntBinOpEvaluator should have handled integral types\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 9459, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert((!E->getLHS()->getType()->isIntegralOrEnumerationType() \|\|
9458	(0) . __assert_fail ("(!E->getLHS()->getType()->isIntegralOrEnumerationType() \|\| !E->getRHS()->getType()->isIntegralOrEnumerationType()) && \"DataRecursiveIntBinOpEvaluator should have handled integral types\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 9459, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true"> !E->getRHS()->getType()->isIntegralOrEnumerationType()) &&
9459	(0) . __assert_fail ("(!E->getLHS()->getType()->isIntegralOrEnumerationType() \|\| !E->getRHS()->getType()->isIntegralOrEnumerationType()) && \"DataRecursiveIntBinOpEvaluator should have handled integral types\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 9459, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true"> "DataRecursiveIntBinOpEvaluator should have handled integral types");
9460
9461	if (E->isComparisonOp()) {
9462	// Evaluate builtin binary comparisons by evaluating them as C++2a three-way
9463	// comparisons and then translating the result.
9464	auto OnSuccess = [&](ComparisonCategoryResult ResKind,
9465	const BinaryOperator *E) {
9466	using CCR = ComparisonCategoryResult;
9467	bool IsEqual = ResKind == CCR::Equal,
9468	IsLess = ResKind == CCR::Less,
9469	IsGreater = ResKind == CCR::Greater;
9470	auto Op = E->getOpcode();
9471	switch (Op) {
9472	default:
9473	llvm_unreachable("unsupported binary operator");
9474	case BO_EQ:
9475	case BO_NE:
9476	return Success(IsEqual == (Op == BO_EQ), E);
9477	case BO_LT: return Success(IsLess, E);
9478	case BO_GT: return Success(IsGreater, E);
9479	case BO_LE: return Success(IsEqual \|\| IsLess, E);
9480	case BO_GE: return Success(IsEqual \|\| IsGreater, E);
9481	}
9482	};
9483	return EvaluateComparisonBinaryOperator(Info, E, OnSuccess, [&]() {
9484	return ExprEvaluatorBaseTy::VisitBinaryOperator(E);
9485	});
9486	}
9487
9488	QualType LHSTy = E->getLHS()->getType();
9489	QualType RHSTy = E->getRHS()->getType();
9490
9491	if (LHSTy->isPointerType() && RHSTy->isPointerType() &&
9492	E->getOpcode() == BO_Sub) {
9493	LValue LHSValue, RHSValue;
9494
9495	bool LHSOK = EvaluatePointer(E->getLHS(), LHSValue, Info);
9496	if (!LHSOK && !Info.noteFailure())
9497	return false;
9498
9499	if (!EvaluatePointer(E->getRHS(), RHSValue, Info) \|\| !LHSOK)
9500	return false;
9501
9502	// Reject differing bases from the normal codepath; we special-case
9503	// comparisons to null.
9504	if (!HasSameBase(LHSValue, RHSValue)) {
9505	// Handle &&A - &&B.
9506	if (!LHSValue.Offset.isZero() \|\| !RHSValue.Offset.isZero())
9507	return Error(E);
9508	const Expr LHSExpr = LHSValue.Base.dyn_cast<const Expr >();
9509	const Expr RHSExpr = RHSValue.Base.dyn_cast<const Expr >();
9510	if (!LHSExpr \|\| !RHSExpr)
9511	return Error(E);
9512	const AddrLabelExpr *LHSAddrExpr = dyn_cast<AddrLabelExpr>(LHSExpr);
9513	const AddrLabelExpr *RHSAddrExpr = dyn_cast<AddrLabelExpr>(RHSExpr);
9514	if (!LHSAddrExpr \|\| !RHSAddrExpr)
9515	return Error(E);
9516	// Make sure both labels come from the same function.
9517	if (LHSAddrExpr->getLabel()->getDeclContext() !=
9518	RHSAddrExpr->getLabel()->getDeclContext())
9519	return Error(E);
9520	return Success(APValue(LHSAddrExpr, RHSAddrExpr), E);
9521	}
9522	const CharUnits &LHSOffset = LHSValue.getLValueOffset();
9523	const CharUnits &RHSOffset = RHSValue.getLValueOffset();
9524
9525	SubobjectDesignator &LHSDesignator = LHSValue.getLValueDesignator();
9526	SubobjectDesignator &RHSDesignator = RHSValue.getLValueDesignator();
9527
9528	// C++11 [expr.add]p6:
9529	// Unless both pointers point to elements of the same array object, or
9530	// one past the last element of the array object, the behavior is
9531	// undefined.
9532	if (!LHSDesignator.Invalid && !RHSDesignator.Invalid &&
9533	!AreElementsOfSameArray(getType(LHSValue.Base), LHSDesignator,
9534	RHSDesignator))
9535	Info.CCEDiag(E, diag::note_constexpr_pointer_subtraction_not_same_array);
9536
9537	QualType Type = E->getLHS()->getType();
9538	QualType ElementType = Type->getAs<PointerType>()->getPointeeType();
9539
9540	CharUnits ElementSize;
9541	if (!HandleSizeof(Info, E->getExprLoc(), ElementType, ElementSize))
9542	return false;
9543
9544	// As an extension, a type may have zero size (empty struct or union in
9545	// C, array of zero length). Pointer subtraction in such cases has
9546	// undefined behavior, so is not constant.
9547	if (ElementSize.isZero()) {
9548	Info.FFDiag(E, diag::note_constexpr_pointer_subtraction_zero_size)
9549	<< ElementType;
9550	return false;
9551	}
9552
9553	// FIXME: LLVM and GCC both compute LHSOffset - RHSOffset at runtime,
9554	// and produce incorrect results when it overflows. Such behavior
9555	// appears to be non-conforming, but is common, so perhaps we should
9556	// assume the standard intended for such cases to be undefined behavior
9557	// and check for them.
9558
9559	// Compute (LHSOffset - RHSOffset) / Size carefully, checking for
9560	// overflow in the final conversion to ptrdiff_t.
9561	APSInt LHS(llvm::APInt(65, (int64_t)LHSOffset.getQuantity(), true), false);
9562	APSInt RHS(llvm::APInt(65, (int64_t)RHSOffset.getQuantity(), true), false);
9563	APSInt ElemSize(llvm::APInt(65, (int64_t)ElementSize.getQuantity(), true),
9564	false);
9565	APSInt TrueResult = (LHS - RHS) / ElemSize;
9566	APSInt Result = TrueResult.trunc(Info.Ctx.getIntWidth(E->getType()));
9567
9568	if (Result.extend(65) != TrueResult &&
9569	!HandleOverflow(Info, E, TrueResult, E->getType()))
9570	return false;
9571	return Success(Result, E);
9572	}
9573
9574	return ExprEvaluatorBaseTy::VisitBinaryOperator(E);
9575	}
9576
9577	/// VisitUnaryExprOrTypeTraitExpr - Evaluate a sizeof, alignof or vec_step with
9578	/// a result as the expression's type.
9579	bool IntExprEvaluator::VisitUnaryExprOrTypeTraitExpr(
9580	const UnaryExprOrTypeTraitExpr *E) {
9581	switch(E->getKind()) {
9582	case UETT_PreferredAlignOf:
9583	case UETT_AlignOf: {
9584	if (E->isArgumentType())
9585	return Success(GetAlignOfType(Info, E->getArgumentType(), E->getKind()),
9586	E);
9587	else
9588	return Success(GetAlignOfExpr(Info, E->getArgumentExpr(), E->getKind()),
9589	E);
9590	}
9591
9592	case UETT_VecStep: {
9593	QualType Ty = E->getTypeOfArgument();
9594
9595	if (Ty->isVectorType()) {
9596	unsigned n = Ty->castAs<VectorType>()->getNumElements();
9597
9598	// The vec_step built-in functions that take a 3-component
9599	// vector return 4. (OpenCL 1.1 spec 6.11.12)
9600	if (n == 3)
9601	n = 4;
9602
9603	return Success(n, E);
9604	} else
9605	return Success(1, E);
9606	}
9607
9608	case UETT_SizeOf: {
9609	QualType SrcTy = E->getTypeOfArgument();
9610	// C++ [expr.sizeof]p2: "When applied to a reference or a reference type,
9611	// the result is the size of the referenced type."
9612	if (const ReferenceType *Ref = SrcTy->getAs<ReferenceType>())
9613	SrcTy = Ref->getPointeeType();
9614
9615	CharUnits Sizeof;
9616	if (!HandleSizeof(Info, E->getExprLoc(), SrcTy, Sizeof))
9617	return false;
9618	return Success(Sizeof, E);
9619	}
9620	case UETT_OpenMPRequiredSimdAlign:
9621	isArgumentType()", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 9621, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(E->isArgumentType());
9622	return Success(
9623	Info.Ctx.toCharUnitsFromBits(
9624	Info.Ctx.getOpenMPDefaultSimdAlign(E->getArgumentType()))
9625	.getQuantity(),
9626	E);
9627	}
9628
9629	llvm_unreachable("unknown expr/type trait");
9630	}
9631
9632	bool IntExprEvaluator::VisitOffsetOfExpr(const OffsetOfExpr *OOE) {
9633	CharUnits Result;
9634	unsigned n = OOE->getNumComponents();
9635	if (n == 0)
9636	return Error(OOE);
9637	QualType CurrentType = OOE->getTypeSourceInfo()->getType();
9638	for (unsigned i = 0; i != n; ++i) {
9639	OffsetOfNode ON = OOE->getComponent(i);
9640	switch (ON.getKind()) {
9641	case OffsetOfNode::Array: {
9642	const Expr *Idx = OOE->getIndexExpr(ON.getArrayExprIndex());
9643	APSInt IdxResult;
9644	if (!EvaluateInteger(Idx, IdxResult, Info))
9645	return false;
9646	const ArrayType *AT = Info.Ctx.getAsArrayType(CurrentType);
9647	if (!AT)
9648	return Error(OOE);
9649	CurrentType = AT->getElementType();
9650	CharUnits ElementSize = Info.Ctx.getTypeSizeInChars(CurrentType);
9651	Result += IdxResult.getSExtValue() * ElementSize;
9652	break;
9653	}
9654
9655	case OffsetOfNode::Field: {
9656	FieldDecl *MemberDecl = ON.getField();
9657	const RecordType *RT = CurrentType->getAs<RecordType>();
9658	if (!RT)
9659	return Error(OOE);
9660	RecordDecl *RD = RT->getDecl();
9661	if (RD->isInvalidDecl()) return false;
9662	const ASTRecordLayout &RL = Info.Ctx.getASTRecordLayout(RD);
9663	unsigned i = MemberDecl->getFieldIndex();
9664	(0) . __assert_fail ("i < RL.getFieldCount() && \"offsetof field in wrong type\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 9664, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(i < RL.getFieldCount() && "offsetof field in wrong type");
9665	Result += Info.Ctx.toCharUnitsFromBits(RL.getFieldOffset(i));
9666	CurrentType = MemberDecl->getType().getNonReferenceType();
9667	break;
9668	}
9669
9670	case OffsetOfNode::Identifier:
9671	llvm_unreachable("dependent __builtin_offsetof");
9672
9673	case OffsetOfNode::Base: {
9674	CXXBaseSpecifier *BaseSpec = ON.getBase();
9675	if (BaseSpec->isVirtual())
9676	return Error(OOE);
9677
9678	// Find the layout of the class whose base we are looking into.
9679	const RecordType *RT = CurrentType->getAs<RecordType>();
9680	if (!RT)
9681	return Error(OOE);
9682	RecordDecl *RD = RT->getDecl();
9683	if (RD->isInvalidDecl()) return false;
9684	const ASTRecordLayout &RL = Info.Ctx.getASTRecordLayout(RD);
9685
9686	// Find the base class itself.
9687	CurrentType = BaseSpec->getType();
9688	const RecordType *BaseRT = CurrentType->getAs<RecordType>();
9689	if (!BaseRT)
9690	return Error(OOE);
9691
9692	// Add the offset to the base.
9693	Result += RL.getBaseClassOffset(cast<CXXRecordDecl>(BaseRT->getDecl()));
9694	break;
9695	}
9696	}
9697	}
9698	return Success(Result, OOE);
9699	}
9700
9701	bool IntExprEvaluator::VisitUnaryOperator(const UnaryOperator *E) {
9702	switch (E->getOpcode()) {
9703	default:
9704	// Address, indirect, pre/post inc/dec, etc are not valid constant exprs.
9705	// See C99 6.6p3.
9706	return Error(E);
9707	case UO_Extension:
9708	// FIXME: Should extension allow i-c-e extension expressions in its scope?
9709	// If so, we could clear the diagnostic ID.
9710	return Visit(E->getSubExpr());
9711	case UO_Plus:
9712	// The result is just the value.
9713	return Visit(E->getSubExpr());
9714	case UO_Minus: {
9715	if (!Visit(E->getSubExpr()))
9716	return false;
9717	if (!Result.isInt()) return Error(E);
9718	const APSInt &Value = Result.getInt();
9719	if (Value.isSigned() && Value.isMinSignedValue() && E->canOverflow() &&
9720	!HandleOverflow(Info, E, -Value.extend(Value.getBitWidth() + 1),
9721	E->getType()))
9722	return false;
9723	return Success(-Value, E);
9724	}
9725	case UO_Not: {
9726	if (!Visit(E->getSubExpr()))
9727	return false;
9728	if (!Result.isInt()) return Error(E);
9729	return Success(~Result.getInt(), E);
9730	}
9731	case UO_LNot: {
9732	bool bres;
9733	if (!EvaluateAsBooleanCondition(E->getSubExpr(), bres, Info))
9734	return false;
9735	return Success(!bres, E);
9736	}
9737	}
9738	}
9739
9740	/// HandleCast - This is used to evaluate implicit or explicit casts where the
9741	/// result type is integer.
9742	bool IntExprEvaluator::VisitCastExpr(const CastExpr *E) {
9743	const Expr *SubExpr = E->getSubExpr();
9744	QualType DestType = E->getType();
9745	QualType SrcType = SubExpr->getType();
9746
9747	switch (E->getCastKind()) {
9748	case CK_BaseToDerived:
9749	case CK_DerivedToBase:
9750	case CK_UncheckedDerivedToBase:
9751	case CK_Dynamic:
9752	case CK_ToUnion:
9753	case CK_ArrayToPointerDecay:
9754	case CK_FunctionToPointerDecay:
9755	case CK_NullToPointer:
9756	case CK_NullToMemberPointer:
9757	case CK_BaseToDerivedMemberPointer:
9758	case CK_DerivedToBaseMemberPointer:
9759	case CK_ReinterpretMemberPointer:
9760	case CK_ConstructorConversion:
9761	case CK_IntegralToPointer:
9762	case CK_ToVoid:
9763	case CK_VectorSplat:
9764	case CK_IntegralToFloating:
9765	case CK_FloatingCast:
9766	case CK_CPointerToObjCPointerCast:
9767	case CK_BlockPointerToObjCPointerCast:
9768	case CK_AnyPointerToBlockPointerCast:
9769	case CK_ObjCObjectLValueCast:
9770	case CK_FloatingRealToComplex:
9771	case CK_FloatingComplexToReal:
9772	case CK_FloatingComplexCast:
9773	case CK_FloatingComplexToIntegralComplex:
9774	case CK_IntegralRealToComplex:
9775	case CK_IntegralComplexCast:
9776	case CK_IntegralComplexToFloatingComplex:
9777	case CK_BuiltinFnToFnPtr:
9778	case CK_ZeroToOCLOpaqueType:
9779	case CK_NonAtomicToAtomic:
9780	case CK_AddressSpaceConversion:
9781	case CK_IntToOCLSampler:
9782	case CK_FixedPointCast:
9783	case CK_IntegralToFixedPoint:
9784	llvm_unreachable("invalid cast kind for integral value");
9785
9786	case CK_BitCast:
9787	case CK_Dependent:
9788	case CK_LValueBitCast:
9789	case CK_ARCProduceObject:
9790	case CK_ARCConsumeObject:
9791	case CK_ARCReclaimReturnedObject:
9792	case CK_ARCExtendBlockObject:
9793	case CK_CopyAndAutoreleaseBlockObject:
9794	return Error(E);
9795
9796	case CK_UserDefinedConversion:
9797	case CK_LValueToRValue:
9798	case CK_AtomicToNonAtomic:
9799	case CK_NoOp:
9800	return ExprEvaluatorBaseTy::VisitCastExpr(E);
9801
9802	case CK_MemberPointerToBoolean:
9803	case CK_PointerToBoolean:
9804	case CK_IntegralToBoolean:
9805	case CK_FloatingToBoolean:
9806	case CK_BooleanToSignedIntegral:
9807	case CK_FloatingComplexToBoolean:
9808	case CK_IntegralComplexToBoolean: {
9809	bool BoolResult;
9810	if (!EvaluateAsBooleanCondition(SubExpr, BoolResult, Info))
9811	return false;
9812	uint64_t IntResult = BoolResult;
9813	if (BoolResult && E->getCastKind() == CK_BooleanToSignedIntegral)
9814	IntResult = (uint64_t)-1;
9815	return Success(IntResult, E);
9816	}
9817
9818	case CK_FixedPointToIntegral: {
9819	APFixedPoint Src(Info.Ctx.getFixedPointSemantics(SrcType));
9820	if (!EvaluateFixedPoint(SubExpr, Src, Info))
9821	return false;
9822	bool Overflowed;
9823	llvm::APSInt Result = Src.convertToInt(
9824	Info.Ctx.getIntWidth(DestType),
9825	DestType->isSignedIntegerOrEnumerationType(), &Overflowed);
9826	if (Overflowed && !HandleOverflow(Info, E, Result, DestType))
9827	return false;
9828	return Success(Result, E);
9829	}
9830
9831	case CK_FixedPointToBoolean: {
9832	// Unsigned padding does not affect this.
9833	APValue Val;
9834	if (!Evaluate(Val, Info, SubExpr))
9835	return false;
9836	return Success(Val.getFixedPoint().getBoolValue(), E);
9837	}
9838
9839	case CK_IntegralCast: {
9840	if (!Visit(SubExpr))
9841	return false;
9842
9843	if (!Result.isInt()) {
9844	// Allow casts of address-of-label differences if they are no-ops
9845	// or narrowing. (The narrowing case isn't actually guaranteed to
9846	// be constant-evaluatable except in some narrow cases which are hard
9847	// to detect here. We let it through on the assumption the user knows
9848	// what they are doing.)
9849	if (Result.isAddrLabelDiff())
9850	return Info.Ctx.getTypeSize(DestType) <= Info.Ctx.getTypeSize(SrcType);
9851	// Only allow casts of lvalues if they are lossless.
9852	return Info.Ctx.getTypeSize(DestType) == Info.Ctx.getTypeSize(SrcType);
9853	}
9854
9855	return Success(HandleIntToIntCast(Info, E, DestType, SrcType,
9856	Result.getInt()), E);
9857	}
9858
9859	case CK_PointerToIntegral: {
9860	CCEDiag(E, diag::note_constexpr_invalid_cast) << 2;
9861
9862	LValue LV;
9863	if (!EvaluatePointer(SubExpr, LV, Info))
9864	return false;
9865
9866	if (LV.getLValueBase()) {
9867	// Only allow based lvalue casts if they are lossless.
9868	// FIXME: Allow a larger integer size than the pointer size, and allow
9869	// narrowing back down to pointer width in subsequent integral casts.
9870	// FIXME: Check integer type's active bits, not its type size.
9871	if (Info.Ctx.getTypeSize(DestType) != Info.Ctx.getTypeSize(SrcType))
9872	return Error(E);
9873
9874	LV.Designator.setInvalid();
9875	LV.moveInto(Result);
9876	return true;
9877	}
9878
9879	APSInt AsInt;
9880	APValue V;
9881	LV.moveInto(V);
9882	if (!V.toIntegralConstant(AsInt, SrcType, Info.Ctx))
9883	llvm_unreachable("Can't cast this!");
9884
9885	return Success(HandleIntToIntCast(Info, E, DestType, SrcType, AsInt), E);
9886	}
9887
9888	case CK_IntegralComplexToReal: {
9889	ComplexValue C;
9890	if (!EvaluateComplex(SubExpr, C, Info))
9891	return false;
9892	return Success(C.getComplexIntReal(), E);
9893	}
9894
9895	case CK_FloatingToIntegral: {
9896	APFloat F(0.0);
9897	if (!EvaluateFloat(SubExpr, F, Info))
9898	return false;
9899
9900	APSInt Value;
9901	if (!HandleFloatToIntCast(Info, E, SrcType, F, DestType, Value))
9902	return false;
9903	return Success(Value, E);
9904	}
9905	}
9906
9907	llvm_unreachable("unknown cast resulting in integral value");
9908	}
9909
9910	bool IntExprEvaluator::VisitUnaryReal(const UnaryOperator *E) {
9911	if (E->getSubExpr()->getType()->isAnyComplexType()) {
9912	ComplexValue LV;
9913	if (!EvaluateComplex(E->getSubExpr(), LV, Info))
9914	return false;
9915	if (!LV.isComplexInt())
9916	return Error(E);
9917	return Success(LV.getComplexIntReal(), E);
9918	}
9919
9920	return Visit(E->getSubExpr());
9921	}
9922
9923	bool IntExprEvaluator::VisitUnaryImag(const UnaryOperator *E) {
9924	if (E->getSubExpr()->getType()->isComplexIntegerType()) {
9925	ComplexValue LV;
9926	if (!EvaluateComplex(E->getSubExpr(), LV, Info))
9927	return false;
9928	if (!LV.isComplexInt())
9929	return Error(E);
9930	return Success(LV.getComplexIntImag(), E);
9931	}
9932
9933	VisitIgnoredValue(E->getSubExpr());
9934	return Success(0, E);
9935	}
9936
9937	bool IntExprEvaluator::VisitSizeOfPackExpr(const SizeOfPackExpr *E) {
9938	return Success(E->getPackLength(), E);
9939	}
9940
9941	bool IntExprEvaluator::VisitCXXNoexceptExpr(const CXXNoexceptExpr *E) {
9942	return Success(E->getValue(), E);
9943	}
9944
9945	bool FixedPointExprEvaluator::VisitUnaryOperator(const UnaryOperator *E) {
9946	switch (E->getOpcode()) {
9947	default:
9948	// Invalid unary operators
9949	return Error(E);
9950	case UO_Plus:
9951	// The result is just the value.
9952	return Visit(E->getSubExpr());
9953	case UO_Minus: {
9954	if (!Visit(E->getSubExpr())) return false;
9955	if (!Result.isFixedPoint())
9956	return Error(E);
9957	bool Overflowed;
9958	APFixedPoint Negated = Result.getFixedPoint().negate(&Overflowed);
9959	if (Overflowed && !HandleOverflow(Info, E, Negated, E->getType()))
9960	return false;
9961	return Success(Negated, E);
9962	}
9963	case UO_LNot: {
9964	bool bres;
9965	if (!EvaluateAsBooleanCondition(E->getSubExpr(), bres, Info))
9966	return false;
9967	return Success(!bres, E);
9968	}
9969	}
9970	}
9971
9972	bool FixedPointExprEvaluator::VisitCastExpr(const CastExpr *E) {
9973	const Expr *SubExpr = E->getSubExpr();
9974	QualType DestType = E->getType();
9975	(0) . __assert_fail ("DestType->isFixedPointType() && \"Expected destination type to be a fixed point type\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 9976, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(DestType->isFixedPointType() &&
9976	(0) . __assert_fail ("DestType->isFixedPointType() && \"Expected destination type to be a fixed point type\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 9976, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true"> "Expected destination type to be a fixed point type");
9977	auto DestFXSema = Info.Ctx.getFixedPointSemantics(DestType);
9978
9979	switch (E->getCastKind()) {
9980	case CK_FixedPointCast: {
9981	APFixedPoint Src(Info.Ctx.getFixedPointSemantics(SubExpr->getType()));
9982	if (!EvaluateFixedPoint(SubExpr, Src, Info))
9983	return false;
9984	bool Overflowed;
9985	APFixedPoint Result = Src.convert(DestFXSema, &Overflowed);
9986	if (Overflowed && !HandleOverflow(Info, E, Result, DestType))
9987	return false;
9988	return Success(Result, E);
9989	}
9990	case CK_IntegralToFixedPoint: {
9991	APSInt Src;
9992	if (!EvaluateInteger(SubExpr, Src, Info))
9993	return false;
9994
9995	bool Overflowed;
9996	APFixedPoint IntResult = APFixedPoint::getFromIntValue(
9997	Src, Info.Ctx.getFixedPointSemantics(DestType), &Overflowed);
9998
9999	if (Overflowed && !HandleOverflow(Info, E, IntResult, DestType))
10000	return false;
10001
10002	return Success(IntResult, E);
10003	}
10004	case CK_NoOp:
10005	case CK_LValueToRValue:
10006	return ExprEvaluatorBaseTy::VisitCastExpr(E);
10007	default:
10008	return Error(E);
10009	}
10010	}
10011
10012	bool FixedPointExprEvaluator::VisitBinaryOperator(const BinaryOperator *E) {
10013	const Expr *LHS = E->getLHS();
10014	const Expr *RHS = E->getRHS();
10015	FixedPointSemantics ResultFXSema =
10016	Info.Ctx.getFixedPointSemantics(E->getType());
10017
10018	APFixedPoint LHSFX(Info.Ctx.getFixedPointSemantics(LHS->getType()));
10019	if (!EvaluateFixedPointOrInteger(LHS, LHSFX, Info))
10020	return false;
10021	APFixedPoint RHSFX(Info.Ctx.getFixedPointSemantics(RHS->getType()));
10022	if (!EvaluateFixedPointOrInteger(RHS, RHSFX, Info))
10023	return false;
10024
10025	switch (E->getOpcode()) {
10026	case BO_Add: {
10027	bool AddOverflow, ConversionOverflow;
10028	APFixedPoint Result = LHSFX.add(RHSFX, &AddOverflow)
10029	.convert(ResultFXSema, &ConversionOverflow);
10030	if ((AddOverflow \|\| ConversionOverflow) &&
10031	!HandleOverflow(Info, E, Result, E->getType()))
10032	return false;
10033	return Success(Result, E);
10034	}
10035	default:
10036	return false;
10037	}
10038	llvm_unreachable("Should've exited before this");
10039	}
10040
10041	//===----------------------------------------------------------------------===//
10042	// Float Evaluation
10043	//===----------------------------------------------------------------------===//
10044
10045	namespace {
10046	class FloatExprEvaluator
10047	: public ExprEvaluatorBase<FloatExprEvaluator> {
10048	APFloat &Result;
10049	public:
10050	FloatExprEvaluator(EvalInfo &info, APFloat &result)
10051	: ExprEvaluatorBaseTy(info), Result(result) {}
10052
10053	bool Success(const APValue &V, const Expr *e) {
10054	Result = V.getFloat();
10055	return true;
10056	}
10057
10058	bool ZeroInitialization(const Expr *E) {
10059	Result = APFloat::getZero(Info.Ctx.getFloatTypeSemantics(E->getType()));
10060	return true;
10061	}
10062
10063	bool VisitCallExpr(const CallExpr *E);
10064
10065	bool VisitUnaryOperator(const UnaryOperator *E);
10066	bool VisitBinaryOperator(const BinaryOperator *E);
10067	bool VisitFloatingLiteral(const FloatingLiteral *E);
10068	bool VisitCastExpr(const CastExpr *E);
10069
10070	bool VisitUnaryReal(const UnaryOperator *E);
10071	bool VisitUnaryImag(const UnaryOperator *E);
10072
10073	// FIXME: Missing: array subscript of vector, member of vector
10074	};
10075	} // end anonymous namespace
10076
10077	static bool EvaluateFloat(const Expr* E, APFloat& Result, EvalInfo &Info) {
10078	isRValue() && E->getType()->isRealFloatingType()", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 10078, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(E->isRValue() && E->getType()->isRealFloatingType());
10079	return FloatExprEvaluator(Info, Result).Visit(E);
10080	}
10081
10082	static bool TryEvaluateBuiltinNaN(const ASTContext &Context,
10083	QualType ResultTy,
10084	const Expr *Arg,
10085	bool SNaN,
10086	llvm::APFloat &Result) {
10087	const StringLiteral *S = dyn_cast<StringLiteral>(Arg->IgnoreParenCasts());
10088	if (!S) return false;
10089
10090	const llvm::fltSemantics &Sem = Context.getFloatTypeSemantics(ResultTy);
10091
10092	llvm::APInt fill;
10093
10094	// Treat empty strings as if they were zero.
10095	if (S->getString().empty())
10096	fill = llvm::APInt(32, 0);
10097	else if (S->getString().getAsInteger(0, fill))
10098	return false;
10099
10100	if (Context.getTargetInfo().isNan2008()) {
10101	if (SNaN)
10102	Result = llvm::APFloat::getSNaN(Sem, false, &fill);
10103	else
10104	Result = llvm::APFloat::getQNaN(Sem, false, &fill);
10105	} else {
10106	// Prior to IEEE 754-2008, architectures were allowed to choose whether
10107	// the first bit of their significand was set for qNaN or sNaN. MIPS chose
10108	// a different encoding to what became a standard in 2008, and for pre-
10109	// 2008 revisions, MIPS interpreted sNaN-2008 as qNan and qNaN-2008 as
10110	// sNaN. This is now known as "legacy NaN" encoding.
10111	if (SNaN)
10112	Result = llvm::APFloat::getQNaN(Sem, false, &fill);
10113	else
10114	Result = llvm::APFloat::getSNaN(Sem, false, &fill);
10115	}
10116
10117	return true;
10118	}
10119
10120	bool FloatExprEvaluator::VisitCallExpr(const CallExpr *E) {
10121	switch (E->getBuiltinCallee()) {
10122	default:
10123	return ExprEvaluatorBaseTy::VisitCallExpr(E);
10124
10125	case Builtin::BI__builtin_huge_val:
10126	case Builtin::BI__builtin_huge_valf:
10127	case Builtin::BI__builtin_huge_vall:
10128	case Builtin::BI__builtin_huge_valf128:
10129	case Builtin::BI__builtin_inf:
10130	case Builtin::BI__builtin_inff:
10131	case Builtin::BI__builtin_infl:
10132	case Builtin::BI__builtin_inff128: {
10133	const llvm::fltSemantics &Sem =
10134	Info.Ctx.getFloatTypeSemantics(E->getType());
10135	Result = llvm::APFloat::getInf(Sem);
10136	return true;
10137	}
10138
10139	case Builtin::BI__builtin_nans:
10140	case Builtin::BI__builtin_nansf:
10141	case Builtin::BI__builtin_nansl:
10142	case Builtin::BI__builtin_nansf128:
10143	if (!TryEvaluateBuiltinNaN(Info.Ctx, E->getType(), E->getArg(0),
10144	true, Result))
10145	return Error(E);
10146	return true;
10147
10148	case Builtin::BI__builtin_nan:
10149	case Builtin::BI__builtin_nanf:
10150	case Builtin::BI__builtin_nanl:
10151	case Builtin::BI__builtin_nanf128:
10152	// If this is __builtin_nan() turn this into a nan, otherwise we
10153	// can't constant fold it.
10154	if (!TryEvaluateBuiltinNaN(Info.Ctx, E->getType(), E->getArg(0),
10155	false, Result))
10156	return Error(E);
10157	return true;
10158
10159	case Builtin::BI__builtin_fabs:
10160	case Builtin::BI__builtin_fabsf:
10161	case Builtin::BI__builtin_fabsl:
10162	case Builtin::BI__builtin_fabsf128:
10163	if (!EvaluateFloat(E->getArg(0), Result, Info))
10164	return false;
10165
10166	if (Result.isNegative())
10167	Result.changeSign();
10168	return true;
10169
10170	// FIXME: Builtin::BI__builtin_powi
10171	// FIXME: Builtin::BI__builtin_powif
10172	// FIXME: Builtin::BI__builtin_powil
10173
10174	case Builtin::BI__builtin_copysign:
10175	case Builtin::BI__builtin_copysignf:
10176	case Builtin::BI__builtin_copysignl:
10177	case Builtin::BI__builtin_copysignf128: {
10178	APFloat RHS(0.);
10179	if (!EvaluateFloat(E->getArg(0), Result, Info) \|\|
10180	!EvaluateFloat(E->getArg(1), RHS, Info))
10181	return false;
10182	Result.copySign(RHS);
10183	return true;
10184	}
10185	}
10186	}
10187
10188	bool FloatExprEvaluator::VisitUnaryReal(const UnaryOperator *E) {
10189	if (E->getSubExpr()->getType()->isAnyComplexType()) {
10190	ComplexValue CV;
10191	if (!EvaluateComplex(E->getSubExpr(), CV, Info))
10192	return false;
10193	Result = CV.FloatReal;
10194	return true;
10195	}
10196
10197	return Visit(E->getSubExpr());
10198	}
10199
10200	bool FloatExprEvaluator::VisitUnaryImag(const UnaryOperator *E) {
10201	if (E->getSubExpr()->getType()->isAnyComplexType()) {
10202	ComplexValue CV;
10203	if (!EvaluateComplex(E->getSubExpr(), CV, Info))
10204	return false;
10205	Result = CV.FloatImag;
10206	return true;
10207	}
10208
10209	VisitIgnoredValue(E->getSubExpr());
10210	const llvm::fltSemantics &Sem = Info.Ctx.getFloatTypeSemantics(E->getType());
10211	Result = llvm::APFloat::getZero(Sem);
10212	return true;
10213	}
10214
10215	bool FloatExprEvaluator::VisitUnaryOperator(const UnaryOperator *E) {
10216	switch (E->getOpcode()) {
10217	default: return Error(E);
10218	case UO_Plus:
10219	return EvaluateFloat(E->getSubExpr(), Result, Info);
10220	case UO_Minus:
10221	if (!EvaluateFloat(E->getSubExpr(), Result, Info))
10222	return false;
10223	Result.changeSign();
10224	return true;
10225	}
10226	}
10227
10228	bool FloatExprEvaluator::VisitBinaryOperator(const BinaryOperator *E) {
10229	if (E->isPtrMemOp() \|\| E->isAssignmentOp() \|\| E->getOpcode() == BO_Comma)
10230	return ExprEvaluatorBaseTy::VisitBinaryOperator(E);
10231
10232	APFloat RHS(0.0);
10233	bool LHSOK = EvaluateFloat(E->getLHS(), Result, Info);
10234	if (!LHSOK && !Info.noteFailure())
10235	return false;
10236	return EvaluateFloat(E->getRHS(), RHS, Info) && LHSOK &&
10237	handleFloatFloatBinOp(Info, E, Result, E->getOpcode(), RHS);
10238	}
10239
10240	bool FloatExprEvaluator::VisitFloatingLiteral(const FloatingLiteral *E) {
10241	Result = E->getValue();
10242	return true;
10243	}
10244
10245	bool FloatExprEvaluator::VisitCastExpr(const CastExpr *E) {
10246	const Expr* SubExpr = E->getSubExpr();
10247
10248	switch (E->getCastKind()) {
10249	default:
10250	return ExprEvaluatorBaseTy::VisitCastExpr(E);
10251
10252	case CK_IntegralToFloating: {
10253	APSInt IntResult;
10254	return EvaluateInteger(SubExpr, IntResult, Info) &&
10255	HandleIntToFloatCast(Info, E, SubExpr->getType(), IntResult,
10256	E->getType(), Result);
10257	}
10258
10259	case CK_FloatingCast: {
10260	if (!Visit(SubExpr))
10261	return false;
10262	return HandleFloatToFloatCast(Info, E, SubExpr->getType(), E->getType(),
10263	Result);
10264	}
10265
10266	case CK_FloatingComplexToReal: {
10267	ComplexValue V;
10268	if (!EvaluateComplex(SubExpr, V, Info))
10269	return false;
10270	Result = V.getComplexFloatReal();
10271	return true;
10272	}
10273	}
10274	}
10275
10276	//===----------------------------------------------------------------------===//
10277	// Complex Evaluation (for float and integer)
10278	//===----------------------------------------------------------------------===//
10279
10280	namespace {
10281	class ComplexExprEvaluator
10282	: public ExprEvaluatorBase<ComplexExprEvaluator> {
10283	ComplexValue &Result;
10284
10285	public:
10286	ComplexExprEvaluator(EvalInfo &info, ComplexValue &Result)
10287	: ExprEvaluatorBaseTy(info), Result(Result) {}
10288
10289	bool Success(const APValue &V, const Expr *e) {
10290	Result.setFrom(V);
10291	return true;
10292	}
10293
10294	bool ZeroInitialization(const Expr *E);
10295
10296	//===--------------------------------------------------------------------===//
10297	// Visitor Methods
10298	//===--------------------------------------------------------------------===//
10299
10300	bool VisitImaginaryLiteral(const ImaginaryLiteral *E);
10301	bool VisitCastExpr(const CastExpr *E);
10302	bool VisitBinaryOperator(const BinaryOperator *E);
10303	bool VisitUnaryOperator(const UnaryOperator *E);
10304	bool VisitInitListExpr(const InitListExpr *E);
10305	};
10306	} // end anonymous namespace
10307
10308	static bool EvaluateComplex(const Expr *E, ComplexValue &Result,
10309	EvalInfo &Info) {
10310	isRValue() && E->getType()->isAnyComplexType()", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 10310, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(E->isRValue() && E->getType()->isAnyComplexType());
10311	return ComplexExprEvaluator(Info, Result).Visit(E);
10312	}
10313
10314	bool ComplexExprEvaluator::ZeroInitialization(const Expr *E) {
10315	QualType ElemTy = E->getType()->castAs<ComplexType>()->getElementType();
10316	if (ElemTy->isRealFloatingType()) {
10317	Result.makeComplexFloat();
10318	APFloat Zero = APFloat::getZero(Info.Ctx.getFloatTypeSemantics(ElemTy));
10319	Result.FloatReal = Zero;
10320	Result.FloatImag = Zero;
10321	} else {
10322	Result.makeComplexInt();
10323	APSInt Zero = Info.Ctx.MakeIntValue(0, ElemTy);
10324	Result.IntReal = Zero;
10325	Result.IntImag = Zero;
10326	}
10327	return true;
10328	}
10329
10330	bool ComplexExprEvaluator::VisitImaginaryLiteral(const ImaginaryLiteral *E) {
10331	const Expr* SubExpr = E->getSubExpr();
10332
10333	if (SubExpr->getType()->isRealFloatingType()) {
10334	Result.makeComplexFloat();
10335	APFloat &Imag = Result.FloatImag;
10336	if (!EvaluateFloat(SubExpr, Imag, Info))
10337	return false;
10338
10339	Result.FloatReal = APFloat(Imag.getSemantics());
10340	return true;
10341	} else {
10342	(0) . __assert_fail ("SubExpr->getType()->isIntegerType() && \"Unexpected imaginary literal.\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 10343, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(SubExpr->getType()->isIntegerType() &&
10343	(0) . __assert_fail ("SubExpr->getType()->isIntegerType() && \"Unexpected imaginary literal.\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 10343, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true"> "Unexpected imaginary literal.");
10344
10345	Result.makeComplexInt();
10346	APSInt &Imag = Result.IntImag;
10347	if (!EvaluateInteger(SubExpr, Imag, Info))
10348	return false;
10349
10350	Result.IntReal = APSInt(Imag.getBitWidth(), !Imag.isSigned());
10351	return true;
10352	}
10353	}
10354
10355	bool ComplexExprEvaluator::VisitCastExpr(const CastExpr *E) {
10356
10357	switch (E->getCastKind()) {
10358	case CK_BitCast:
10359	case CK_BaseToDerived:
10360	case CK_DerivedToBase:
10361	case CK_UncheckedDerivedToBase:
10362	case CK_Dynamic:
10363	case CK_ToUnion:
10364	case CK_ArrayToPointerDecay:
10365	case CK_FunctionToPointerDecay:
10366	case CK_NullToPointer:
10367	case CK_NullToMemberPointer:
10368	case CK_BaseToDerivedMemberPointer:
10369	case CK_DerivedToBaseMemberPointer:
10370	case CK_MemberPointerToBoolean:
10371	case CK_ReinterpretMemberPointer:
10372	case CK_ConstructorConversion:
10373	case CK_IntegralToPointer:
10374	case CK_PointerToIntegral:
10375	case CK_PointerToBoolean:
10376	case CK_ToVoid:
10377	case CK_VectorSplat:
10378	case CK_IntegralCast:
10379	case CK_BooleanToSignedIntegral:
10380	case CK_IntegralToBoolean:
10381	case CK_IntegralToFloating:
10382	case CK_FloatingToIntegral:
10383	case CK_FloatingToBoolean:
10384	case CK_FloatingCast:
10385	case CK_CPointerToObjCPointerCast:
10386	case CK_BlockPointerToObjCPointerCast:
10387	case CK_AnyPointerToBlockPointerCast:
10388	case CK_ObjCObjectLValueCast:
10389	case CK_FloatingComplexToReal:
10390	case CK_FloatingComplexToBoolean:
10391	case CK_IntegralComplexToReal:
10392	case CK_IntegralComplexToBoolean:
10393	case CK_ARCProduceObject:
10394	case CK_ARCConsumeObject:
10395	case CK_ARCReclaimReturnedObject:
10396	case CK_ARCExtendBlockObject:
10397	case CK_CopyAndAutoreleaseBlockObject:
10398	case CK_BuiltinFnToFnPtr:
10399	case CK_ZeroToOCLOpaqueType:
10400	case CK_NonAtomicToAtomic:
10401	case CK_AddressSpaceConversion:
10402	case CK_IntToOCLSampler:
10403	case CK_FixedPointCast:
10404	case CK_FixedPointToBoolean:
10405	case CK_FixedPointToIntegral:
10406	case CK_IntegralToFixedPoint:
10407	llvm_unreachable("invalid cast kind for complex value");
10408
10409	case CK_LValueToRValue:
10410	case CK_AtomicToNonAtomic:
10411	case CK_NoOp:
10412	return ExprEvaluatorBaseTy::VisitCastExpr(E);
10413
10414	case CK_Dependent:
10415	case CK_LValueBitCast:
10416	case CK_UserDefinedConversion:
10417	return Error(E);
10418
10419	case CK_FloatingRealToComplex: {
10420	APFloat &Real = Result.FloatReal;
10421	if (!EvaluateFloat(E->getSubExpr(), Real, Info))
10422	return false;
10423
10424	Result.makeComplexFloat();
10425	Result.FloatImag = APFloat(Real.getSemantics());
10426	return true;
10427	}
10428
10429	case CK_FloatingComplexCast: {
10430	if (!Visit(E->getSubExpr()))
10431	return false;
10432
10433	QualType To = E->getType()->getAs<ComplexType>()->getElementType();
10434	QualType From
10435	= E->getSubExpr()->getType()->getAs<ComplexType>()->getElementType();
10436
10437	return HandleFloatToFloatCast(Info, E, From, To, Result.FloatReal) &&
10438	HandleFloatToFloatCast(Info, E, From, To, Result.FloatImag);
10439	}
10440
10441	case CK_FloatingComplexToIntegralComplex: {
10442	if (!Visit(E->getSubExpr()))
10443	return false;
10444
10445	QualType To = E->getType()->getAs<ComplexType>()->getElementType();
10446	QualType From
10447	= E->getSubExpr()->getType()->getAs<ComplexType>()->getElementType();
10448	Result.makeComplexInt();
10449	return HandleFloatToIntCast(Info, E, From, Result.FloatReal,
10450	To, Result.IntReal) &&
10451	HandleFloatToIntCast(Info, E, From, Result.FloatImag,
10452	To, Result.IntImag);
10453	}
10454
10455	case CK_IntegralRealToComplex: {
10456	APSInt &Real = Result.IntReal;
10457	if (!EvaluateInteger(E->getSubExpr(), Real, Info))
10458	return false;
10459
10460	Result.makeComplexInt();
10461	Result.IntImag = APSInt(Real.getBitWidth(), !Real.isSigned());
10462	return true;
10463	}
10464
10465	case CK_IntegralComplexCast: {
10466	if (!Visit(E->getSubExpr()))
10467	return false;
10468
10469	QualType To = E->getType()->getAs<ComplexType>()->getElementType();
10470	QualType From
10471	= E->getSubExpr()->getType()->getAs<ComplexType>()->getElementType();
10472
10473	Result.IntReal = HandleIntToIntCast(Info, E, To, From, Result.IntReal);
10474	Result.IntImag = HandleIntToIntCast(Info, E, To, From, Result.IntImag);
10475	return true;
10476	}
10477
10478	case CK_IntegralComplexToFloatingComplex: {
10479	if (!Visit(E->getSubExpr()))
10480	return false;
10481
10482	QualType To = E->getType()->castAs<ComplexType>()->getElementType();
10483	QualType From
10484	= E->getSubExpr()->getType()->castAs<ComplexType>()->getElementType();
10485	Result.makeComplexFloat();
10486	return HandleIntToFloatCast(Info, E, From, Result.IntReal,
10487	To, Result.FloatReal) &&
10488	HandleIntToFloatCast(Info, E, From, Result.IntImag,
10489	To, Result.FloatImag);
10490	}
10491	}
10492
10493	llvm_unreachable("unknown cast resulting in complex value");
10494	}
10495
10496	bool ComplexExprEvaluator::VisitBinaryOperator(const BinaryOperator *E) {
10497	if (E->isPtrMemOp() \|\| E->isAssignmentOp() \|\| E->getOpcode() == BO_Comma)
10498	return ExprEvaluatorBaseTy::VisitBinaryOperator(E);
10499
10500	// Track whether the LHS or RHS is real at the type system level. When this is
10501	// the case we can simplify our evaluation strategy.
10502	bool LHSReal = false, RHSReal = false;
10503
10504	bool LHSOK;
10505	if (E->getLHS()->getType()->isRealFloatingType()) {
10506	LHSReal = true;
10507	APFloat &Real = Result.FloatReal;
10508	LHSOK = EvaluateFloat(E->getLHS(), Real, Info);
10509	if (LHSOK) {
10510	Result.makeComplexFloat();
10511	Result.FloatImag = APFloat(Real.getSemantics());
10512	}
10513	} else {
10514	LHSOK = Visit(E->getLHS());
10515	}
10516	if (!LHSOK && !Info.noteFailure())
10517	return false;
10518
10519	ComplexValue RHS;
10520	if (E->getRHS()->getType()->isRealFloatingType()) {
10521	RHSReal = true;
10522	APFloat &Real = RHS.FloatReal;
10523	if (!EvaluateFloat(E->getRHS(), Real, Info) \|\| !LHSOK)
10524	return false;
10525	RHS.makeComplexFloat();
10526	RHS.FloatImag = APFloat(Real.getSemantics());
10527	} else if (!EvaluateComplex(E->getRHS(), RHS, Info) \|\| !LHSOK)
10528	return false;
10529
10530	(0) . __assert_fail ("!(LHSReal && RHSReal) && \"Cannot have both operands of a complex operation be real.\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 10531, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(!(LHSReal && RHSReal) &&
10531	(0) . __assert_fail ("!(LHSReal && RHSReal) && \"Cannot have both operands of a complex operation be real.\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 10531, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true"> "Cannot have both operands of a complex operation be real.");
10532	switch (E->getOpcode()) {
10533	default: return Error(E);
10534	case BO_Add:
10535	if (Result.isComplexFloat()) {
10536	Result.getComplexFloatReal().add(RHS.getComplexFloatReal(),
10537	APFloat::rmNearestTiesToEven);
10538	if (LHSReal)
10539	Result.getComplexFloatImag() = RHS.getComplexFloatImag();
10540	else if (!RHSReal)
10541	Result.getComplexFloatImag().add(RHS.getComplexFloatImag(),
10542	APFloat::rmNearestTiesToEven);
10543	} else {
10544	Result.getComplexIntReal() += RHS.getComplexIntReal();
10545	Result.getComplexIntImag() += RHS.getComplexIntImag();
10546	}
10547	break;
10548	case BO_Sub:
10549	if (Result.isComplexFloat()) {
10550	Result.getComplexFloatReal().subtract(RHS.getComplexFloatReal(),
10551	APFloat::rmNearestTiesToEven);
10552	if (LHSReal) {
10553	Result.getComplexFloatImag() = RHS.getComplexFloatImag();
10554	Result.getComplexFloatImag().changeSign();
10555	} else if (!RHSReal) {
10556	Result.getComplexFloatImag().subtract(RHS.getComplexFloatImag(),
10557	APFloat::rmNearestTiesToEven);
10558	}
10559	} else {
10560	Result.getComplexIntReal() -= RHS.getComplexIntReal();
10561	Result.getComplexIntImag() -= RHS.getComplexIntImag();
10562	}
10563	break;
10564	case BO_Mul:
10565	if (Result.isComplexFloat()) {
10566	// This is an implementation of complex multiplication according to the
10567	// constraints laid out in C11 Annex G. The implementation uses the
10568	// following naming scheme:
10569	// (a + ib) * (c + id)
10570	ComplexValue LHS = Result;
10571	APFloat &A = LHS.getComplexFloatReal();
10572	APFloat &B = LHS.getComplexFloatImag();
10573	APFloat &C = RHS.getComplexFloatReal();
10574	APFloat &D = RHS.getComplexFloatImag();
10575	APFloat &ResR = Result.getComplexFloatReal();
10576	APFloat &ResI = Result.getComplexFloatImag();
10577	if (LHSReal) {
10578	(0) . __assert_fail ("!RHSReal && \"Cannot have two real operands for a complex op!\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 10578, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(!RHSReal && "Cannot have two real operands for a complex op!");
10579	ResR = A * C;
10580	ResI = A * D;
10581	} else if (RHSReal) {
10582	ResR = C * A;
10583	ResI = C * B;
10584	} else {
10585	// In the fully general case, we need to handle NaNs and infinities
10586	// robustly.
10587	APFloat AC = A * C;
10588	APFloat BD = B * D;
10589	APFloat AD = A * D;
10590	APFloat BC = B * C;
10591	ResR = AC - BD;
10592	ResI = AD + BC;
10593	if (ResR.isNaN() && ResI.isNaN()) {
10594	bool Recalc = false;
10595	if (A.isInfinity() \|\| B.isInfinity()) {
10596	A = APFloat::copySign(
10597	APFloat(A.getSemantics(), A.isInfinity() ? 1 : 0), A);
10598	B = APFloat::copySign(
10599	APFloat(B.getSemantics(), B.isInfinity() ? 1 : 0), B);
10600	if (C.isNaN())
10601	C = APFloat::copySign(APFloat(C.getSemantics()), C);
10602	if (D.isNaN())
10603	D = APFloat::copySign(APFloat(D.getSemantics()), D);
10604	Recalc = true;
10605	}
10606	if (C.isInfinity() \|\| D.isInfinity()) {
10607	C = APFloat::copySign(
10608	APFloat(C.getSemantics(), C.isInfinity() ? 1 : 0), C);
10609	D = APFloat::copySign(
10610	APFloat(D.getSemantics(), D.isInfinity() ? 1 : 0), D);
10611	if (A.isNaN())
10612	A = APFloat::copySign(APFloat(A.getSemantics()), A);
10613	if (B.isNaN())
10614	B = APFloat::copySign(APFloat(B.getSemantics()), B);
10615	Recalc = true;
10616	}
10617	if (!Recalc && (AC.isInfinity() \|\| BD.isInfinity() \|\|
10618	AD.isInfinity() \|\| BC.isInfinity())) {
10619	if (A.isNaN())
10620	A = APFloat::copySign(APFloat(A.getSemantics()), A);
10621	if (B.isNaN())
10622	B = APFloat::copySign(APFloat(B.getSemantics()), B);
10623	if (C.isNaN())
10624	C = APFloat::copySign(APFloat(C.getSemantics()), C);
10625	if (D.isNaN())
10626	D = APFloat::copySign(APFloat(D.getSemantics()), D);
10627	Recalc = true;
10628	}
10629	if (Recalc) {
10630	ResR = APFloat::getInf(A.getSemantics()) * (A * C - B * D);
10631	ResI = APFloat::getInf(A.getSemantics()) * (A * D + B * C);
10632	}
10633	}
10634	}
10635	} else {
10636	ComplexValue LHS = Result;
10637	Result.getComplexIntReal() =
10638	(LHS.getComplexIntReal() * RHS.getComplexIntReal() -
10639	LHS.getComplexIntImag() * RHS.getComplexIntImag());
10640	Result.getComplexIntImag() =
10641	(LHS.getComplexIntReal() * RHS.getComplexIntImag() +
10642	LHS.getComplexIntImag() * RHS.getComplexIntReal());
10643	}
10644	break;
10645	case BO_Div:
10646	if (Result.isComplexFloat()) {
10647	// This is an implementation of complex division according to the
10648	// constraints laid out in C11 Annex G. The implementation uses the
10649	// following naming scheme:
10650	// (a + ib) / (c + id)
10651	ComplexValue LHS = Result;
10652	APFloat &A = LHS.getComplexFloatReal();
10653	APFloat &B = LHS.getComplexFloatImag();
10654	APFloat &C = RHS.getComplexFloatReal();
10655	APFloat &D = RHS.getComplexFloatImag();
10656	APFloat &ResR = Result.getComplexFloatReal();
10657	APFloat &ResI = Result.getComplexFloatImag();
10658	if (RHSReal) {
10659	ResR = A / C;
10660	ResI = B / C;
10661	} else {
10662	if (LHSReal) {
10663	// No real optimizations we can do here, stub out with zero.
10664	B = APFloat::getZero(A.getSemantics());
10665	}
10666	int DenomLogB = 0;
10667	APFloat MaxCD = maxnum(abs(C), abs(D));
10668	if (MaxCD.isFinite()) {
10669	DenomLogB = ilogb(MaxCD);
10670	C = scalbn(C, -DenomLogB, APFloat::rmNearestTiesToEven);
10671	D = scalbn(D, -DenomLogB, APFloat::rmNearestTiesToEven);
10672	}
10673	APFloat Denom = C * C + D * D;
10674	ResR = scalbn((A * C + B * D) / Denom, -DenomLogB,
10675	APFloat::rmNearestTiesToEven);
10676	ResI = scalbn((B * C - A * D) / Denom, -DenomLogB,
10677	APFloat::rmNearestTiesToEven);
10678	if (ResR.isNaN() && ResI.isNaN()) {
10679	if (Denom.isPosZero() && (!A.isNaN() \|\| !B.isNaN())) {
10680	ResR = APFloat::getInf(ResR.getSemantics(), C.isNegative()) * A;
10681	ResI = APFloat::getInf(ResR.getSemantics(), C.isNegative()) * B;
10682	} else if ((A.isInfinity() \|\| B.isInfinity()) && C.isFinite() &&
10683	D.isFinite()) {
10684	A = APFloat::copySign(
10685	APFloat(A.getSemantics(), A.isInfinity() ? 1 : 0), A);
10686	B = APFloat::copySign(
10687	APFloat(B.getSemantics(), B.isInfinity() ? 1 : 0), B);
10688	ResR = APFloat::getInf(ResR.getSemantics()) * (A * C + B * D);
10689	ResI = APFloat::getInf(ResI.getSemantics()) * (B * C - A * D);
10690	} else if (MaxCD.isInfinity() && A.isFinite() && B.isFinite()) {
10691	C = APFloat::copySign(
10692	APFloat(C.getSemantics(), C.isInfinity() ? 1 : 0), C);
10693	D = APFloat::copySign(
10694	APFloat(D.getSemantics(), D.isInfinity() ? 1 : 0), D);
10695	ResR = APFloat::getZero(ResR.getSemantics()) * (A * C + B * D);
10696	ResI = APFloat::getZero(ResI.getSemantics()) * (B * C - A * D);
10697	}
10698	}
10699	}
10700	} else {
10701	if (RHS.getComplexIntReal() == 0 && RHS.getComplexIntImag() == 0)
10702	return Error(E, diag::note_expr_divide_by_zero);
10703
10704	ComplexValue LHS = Result;
10705	APSInt Den = RHS.getComplexIntReal() * RHS.getComplexIntReal() +
10706	RHS.getComplexIntImag() * RHS.getComplexIntImag();
10707	Result.getComplexIntReal() =
10708	(LHS.getComplexIntReal() * RHS.getComplexIntReal() +
10709	LHS.getComplexIntImag() * RHS.getComplexIntImag()) / Den;
10710	Result.getComplexIntImag() =
10711	(LHS.getComplexIntImag() * RHS.getComplexIntReal() -
10712	LHS.getComplexIntReal() * RHS.getComplexIntImag()) / Den;
10713	}
10714	break;
10715	}
10716
10717	return true;
10718	}
10719
10720	bool ComplexExprEvaluator::VisitUnaryOperator(const UnaryOperator *E) {
10721	// Get the operand value into 'Result'.
10722	if (!Visit(E->getSubExpr()))
10723	return false;
10724
10725	switch (E->getOpcode()) {
10726	default:
10727	return Error(E);
10728	case UO_Extension:
10729	return true;
10730	case UO_Plus:
10731	// The result is always just the subexpr.
10732	return true;
10733	case UO_Minus:
10734	if (Result.isComplexFloat()) {
10735	Result.getComplexFloatReal().changeSign();
10736	Result.getComplexFloatImag().changeSign();
10737	}
10738	else {
10739	Result.getComplexIntReal() = -Result.getComplexIntReal();
10740	Result.getComplexIntImag() = -Result.getComplexIntImag();
10741	}
10742	return true;
10743	case UO_Not:
10744	if (Result.isComplexFloat())
10745	Result.getComplexFloatImag().changeSign();
10746	else
10747	Result.getComplexIntImag() = -Result.getComplexIntImag();
10748	return true;
10749	}
10750	}
10751
10752	bool ComplexExprEvaluator::VisitInitListExpr(const InitListExpr *E) {
10753	if (E->getNumInits() == 2) {
10754	if (E->getType()->isComplexType()) {
10755	Result.makeComplexFloat();
10756	if (!EvaluateFloat(E->getInit(0), Result.FloatReal, Info))
10757	return false;
10758	if (!EvaluateFloat(E->getInit(1), Result.FloatImag, Info))
10759	return false;
10760	} else {
10761	Result.makeComplexInt();
10762	if (!EvaluateInteger(E->getInit(0), Result.IntReal, Info))
10763	return false;
10764	if (!EvaluateInteger(E->getInit(1), Result.IntImag, Info))
10765	return false;
10766	}
10767	return true;
10768	}
10769	return ExprEvaluatorBaseTy::VisitInitListExpr(E);
10770	}
10771
10772	//===----------------------------------------------------------------------===//
10773	// Atomic expression evaluation, essentially just handling the NonAtomicToAtomic
10774	// implicit conversion.
10775	//===----------------------------------------------------------------------===//
10776
10777	namespace {
10778	class AtomicExprEvaluator :
10779	public ExprEvaluatorBase<AtomicExprEvaluator> {
10780	const LValue *This;
10781	APValue &Result;
10782	public:
10783	AtomicExprEvaluator(EvalInfo &Info, const LValue *This, APValue &Result)
10784	: ExprEvaluatorBaseTy(Info), This(This), Result(Result) {}
10785
10786	bool Success(const APValue &V, const Expr *E) {
10787	Result = V;
10788	return true;
10789	}
10790
10791	bool ZeroInitialization(const Expr *E) {
10792	ImplicitValueInitExpr VIE(
10793	E->getType()->castAs<AtomicType>()->getValueType());
10794	// For atomic-qualified class (and array) types in C++, initialize the
10795	// _Atomic-wrapped subobject directly, in-place.
10796	return This ? EvaluateInPlace(Result, Info, *This, &VIE)
10797	: Evaluate(Result, Info, &VIE);
10798	}
10799
10800	bool VisitCastExpr(const CastExpr *E) {
10801	switch (E->getCastKind()) {
10802	default:
10803	return ExprEvaluatorBaseTy::VisitCastExpr(E);
10804	case CK_NonAtomicToAtomic:
10805	return This ? EvaluateInPlace(Result, Info, *This, E->getSubExpr())
10806	: Evaluate(Result, Info, E->getSubExpr());
10807	}
10808	}
10809	};
10810	} // end anonymous namespace
10811
10812	static bool EvaluateAtomic(const Expr E, const LValue This, APValue &Result,
10813	EvalInfo &Info) {
10814	isRValue() && E->getType()->isAtomicType()", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 10814, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(E->isRValue() && E->getType()->isAtomicType());
10815	return AtomicExprEvaluator(Info, This, Result).Visit(E);
10816	}
10817
10818	//===----------------------------------------------------------------------===//
10819	// Void expression evaluation, primarily for a cast to void on the LHS of a
10820	// comma operator
10821	//===----------------------------------------------------------------------===//
10822
10823	namespace {
10824	class VoidExprEvaluator
10825	: public ExprEvaluatorBase<VoidExprEvaluator> {
10826	public:
10827	VoidExprEvaluator(EvalInfo &Info) : ExprEvaluatorBaseTy(Info) {}
10828
10829	bool Success(const APValue &V, const Expr *e) { return true; }
10830
10831	bool ZeroInitialization(const Expr *E) { return true; }
10832
10833	bool VisitCastExpr(const CastExpr *E) {
10834	switch (E->getCastKind()) {
10835	default:
10836	return ExprEvaluatorBaseTy::VisitCastExpr(E);
10837	case CK_ToVoid:
10838	VisitIgnoredValue(E->getSubExpr());
10839	return true;
10840	}
10841	}
10842
10843	bool VisitCallExpr(const CallExpr *E) {
10844	switch (E->getBuiltinCallee()) {
10845	default:
10846	return ExprEvaluatorBaseTy::VisitCallExpr(E);
10847	case Builtin::BI__assume:
10848	case Builtin::BI__builtin_assume:
10849	// The argument is not evaluated!
10850	return true;
10851	}
10852	}
10853	};
10854	} // end anonymous namespace
10855
10856	static bool EvaluateVoid(const Expr *E, EvalInfo &Info) {
10857	isRValue() && E->getType()->isVoidType()", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 10857, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(E->isRValue() && E->getType()->isVoidType());
10858	return VoidExprEvaluator(Info).Visit(E);
10859	}
10860
10861	//===----------------------------------------------------------------------===//
10862	// Top level Expr::EvaluateAsRValue method.
10863	//===----------------------------------------------------------------------===//
10864
10865	static bool Evaluate(APValue &Result, EvalInfo &Info, const Expr *E) {
10866	// In C, function designators are not lvalues, but we evaluate them as if they
10867	// are.
10868	QualType T = E->getType();
10869	if (E->isGLValue() \|\| T->isFunctionType()) {
10870	LValue LV;
10871	if (!EvaluateLValue(E, LV, Info))
10872	return false;
10873	LV.moveInto(Result);
10874	} else if (T->isVectorType()) {
10875	if (!EvaluateVector(E, Result, Info))
10876	return false;
10877	} else if (T->isIntegralOrEnumerationType()) {
10878	if (!IntExprEvaluator(Info, Result).Visit(E))
10879	return false;
10880	} else if (T->hasPointerRepresentation()) {
10881	LValue LV;
10882	if (!EvaluatePointer(E, LV, Info))
10883	return false;
10884	LV.moveInto(Result);
10885	} else if (T->isRealFloatingType()) {
10886	llvm::APFloat F(0.0);
10887	if (!EvaluateFloat(E, F, Info))
10888	return false;
10889	Result = APValue(F);
10890	} else if (T->isAnyComplexType()) {
10891	ComplexValue C;
10892	if (!EvaluateComplex(E, C, Info))
10893	return false;
10894	C.moveInto(Result);
10895	} else if (T->isFixedPointType()) {
10896	if (!FixedPointExprEvaluator(Info, Result).Visit(E)) return false;
10897	} else if (T->isMemberPointerType()) {
10898	MemberPtr P;
10899	if (!EvaluateMemberPointer(E, P, Info))
10900	return false;
10901	P.moveInto(Result);
10902	return true;
10903	} else if (T->isArrayType()) {
10904	LValue LV;
10905	APValue &Value = createTemporary(E, false, LV, *Info.CurrentCall);
10906	if (!EvaluateArray(E, LV, Value, Info))
10907	return false;
10908	Result = Value;
10909	} else if (T->isRecordType()) {
10910	LValue LV;
10911	APValue &Value = createTemporary(E, false, LV, *Info.CurrentCall);
10912	if (!EvaluateRecord(E, LV, Value, Info))
10913	return false;
10914	Result = Value;
10915	} else if (T->isVoidType()) {
10916	if (!Info.getLangOpts().CPlusPlus11)
10917	Info.CCEDiag(E, diag::note_constexpr_nonliteral)
10918	<< E->getType();
10919	if (!EvaluateVoid(E, Info))
10920	return false;
10921	} else if (T->isAtomicType()) {
10922	QualType Unqual = T.getAtomicUnqualifiedType();
10923	if (Unqual->isArrayType() \|\| Unqual->isRecordType()) {
10924	LValue LV;
10925	APValue &Value = createTemporary(E, false, LV, *Info.CurrentCall);
10926	if (!EvaluateAtomic(E, &LV, Value, Info))
10927	return false;
10928	} else {
10929	if (!EvaluateAtomic(E, nullptr, Result, Info))
10930	return false;
10931	}
10932	} else if (Info.getLangOpts().CPlusPlus11) {
10933	Info.FFDiag(E, diag::note_constexpr_nonliteral) << E->getType();
10934	return false;
10935	} else {
10936	Info.FFDiag(E, diag::note_invalid_subexpr_in_const_expr);
10937	return false;
10938	}
10939
10940	return true;
10941	}
10942
10943	/// EvaluateInPlace - Evaluate an expression in-place in an APValue. In some
10944	/// cases, the in-place evaluation is essential, since later initializers for
10945	/// an object can indirectly refer to subobjects which were initialized earlier.
10946	static bool EvaluateInPlace(APValue &Result, EvalInfo &Info, const LValue &This,
10947	const Expr *E, bool AllowNonLiteralTypes) {
10948	isValueDependent()", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 10948, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(!E->isValueDependent());
10949
10950	if (!AllowNonLiteralTypes && !CheckLiteralType(Info, E, &This))
10951	return false;
10952
10953	if (E->isRValue()) {
10954	// Evaluate arrays and record types in-place, so that later initializers can
10955	// refer to earlier-initialized members of the object.
10956	QualType T = E->getType();
10957	if (T->isArrayType())
10958	return EvaluateArray(E, This, Result, Info);
10959	else if (T->isRecordType())
10960	return EvaluateRecord(E, This, Result, Info);
10961	else if (T->isAtomicType()) {
10962	QualType Unqual = T.getAtomicUnqualifiedType();
10963	if (Unqual->isArrayType() \|\| Unqual->isRecordType())
10964	return EvaluateAtomic(E, &This, Result, Info);
10965	}
10966	}
10967
10968	// For any other type, in-place evaluation is unimportant.
10969	return Evaluate(Result, Info, E);
10970	}
10971
10972	/// EvaluateAsRValue - Try to evaluate this expression, performing an implicit
10973	/// lvalue-to-rvalue cast if it is an lvalue.
10974	static bool EvaluateAsRValue(EvalInfo &Info, const Expr *E, APValue &Result) {
10975	if (E->getType().isNull())
10976	return false;
10977
10978	if (!CheckLiteralType(Info, E))
10979	return false;
10980
10981	if (!::Evaluate(Result, Info, E))
10982	return false;
10983
10984	if (E->isGLValue()) {
10985	LValue LV;
10986	LV.setFrom(Info.Ctx, Result);
10987	if (!handleLValueToRValueConversion(Info, E, E->getType(), LV, Result))
10988	return false;
10989	}
10990
10991	// Check this core constant expression is a constant expression.
10992	return CheckConstantExpression(Info, E->getExprLoc(), E->getType(), Result);
10993	}
10994
10995	static bool FastEvaluateAsRValue(const Expr *Exp, Expr::EvalResult &Result,
10996	const ASTContext &Ctx, bool &IsConst) {
10997	// Fast-path evaluations of integer literals, since we sometimes see files
10998	// containing vast quantities of these.
10999	if (const IntegerLiteral *L = dyn_cast<IntegerLiteral>(Exp)) {
11000	Result.Val = APValue(APSInt(L->getValue(),
11001	L->getType()->isUnsignedIntegerType()));
11002	IsConst = true;
11003	return true;
11004	}
11005
11006	// This case should be rare, but we need to check it before we check on
11007	// the type below.
11008	if (Exp->getType().isNull()) {
11009	IsConst = false;
11010	return true;
11011	}
11012
11013	// FIXME: Evaluating values of large array and record types can cause
11014	// performance problems. Only do so in C++11 for now.
11015	if (Exp->isRValue() && (Exp->getType()->isArrayType() \|\|
11016	Exp->getType()->isRecordType()) &&
11017	!Ctx.getLangOpts().CPlusPlus11) {
11018	IsConst = false;
11019	return true;
11020	}
11021	return false;
11022	}
11023
11024	static bool hasUnacceptableSideEffect(Expr::EvalStatus &Result,
11025	Expr::SideEffectsKind SEK) {
11026	return (SEK < Expr::SE_AllowSideEffects && Result.HasSideEffects) \|\|
11027	(SEK < Expr::SE_AllowUndefinedBehavior && Result.HasUndefinedBehavior);
11028	}
11029
11030	static bool EvaluateAsRValue(const Expr *E, Expr::EvalResult &Result,
11031	const ASTContext &Ctx, EvalInfo &Info) {
11032	bool IsConst;
11033	if (FastEvaluateAsRValue(E, Result, Ctx, IsConst))
11034	return IsConst;
11035
11036	return EvaluateAsRValue(Info, E, Result.Val);
11037	}
11038
11039	static bool EvaluateAsInt(const Expr *E, Expr::EvalResult &ExprResult,
11040	const ASTContext &Ctx,
11041	Expr::SideEffectsKind AllowSideEffects,
11042	EvalInfo &Info) {
11043	if (!E->getType()->isIntegralOrEnumerationType())
11044	return false;
11045
11046	if (!::EvaluateAsRValue(E, ExprResult, Ctx, Info) \|\|
11047	!ExprResult.Val.isInt() \|\|
11048	hasUnacceptableSideEffect(ExprResult, AllowSideEffects))
11049	return false;
11050
11051	return true;
11052	}
11053
11054	static bool EvaluateAsFixedPoint(const Expr *E, Expr::EvalResult &ExprResult,
11055	const ASTContext &Ctx,
11056	Expr::SideEffectsKind AllowSideEffects,
11057	EvalInfo &Info) {
11058	if (!E->getType()->isFixedPointType())
11059	return false;
11060
11061	if (!::EvaluateAsRValue(E, ExprResult, Ctx, Info))
11062	return false;
11063
11064	if (!ExprResult.Val.isFixedPoint() \|\|
11065	hasUnacceptableSideEffect(ExprResult, AllowSideEffects))
11066	return false;
11067
11068	return true;
11069	}
11070
11071	/// EvaluateAsRValue - Return true if this is a constant which we can fold using
11072	/// any crazy technique (that has nothing to do with language standards) that
11073	/// we want to. If this function returns true, it returns the folded constant
11074	/// in Result. If this expression is a glvalue, an lvalue-to-rvalue conversion
11075	/// will be applied to the result.
11076	bool Expr::EvaluateAsRValue(EvalResult &Result, const ASTContext &Ctx,
11077	bool InConstantContext) const {
11078	EvalInfo Info(Ctx, Result, EvalInfo::EM_IgnoreSideEffects);
11079	Info.InConstantContext = InConstantContext;
11080	return ::EvaluateAsRValue(this, Result, Ctx, Info);
11081	}
11082
11083	bool Expr::EvaluateAsBooleanCondition(bool &Result,
11084	const ASTContext &Ctx) const {
11085	EvalResult Scratch;
11086	return EvaluateAsRValue(Scratch, Ctx) &&
11087	HandleConversionToBool(Scratch.Val, Result);
11088	}
11089
11090	bool Expr::EvaluateAsInt(EvalResult &Result, const ASTContext &Ctx,
11091	SideEffectsKind AllowSideEffects) const {
11092	EvalInfo Info(Ctx, Result, EvalInfo::EM_IgnoreSideEffects);
11093	return ::EvaluateAsInt(this, Result, Ctx, AllowSideEffects, Info);
11094	}
11095
11096	bool Expr::EvaluateAsFixedPoint(EvalResult &Result, const ASTContext &Ctx,
11097	SideEffectsKind AllowSideEffects) const {
11098	EvalInfo Info(Ctx, Result, EvalInfo::EM_IgnoreSideEffects);
11099	return ::EvaluateAsFixedPoint(this, Result, Ctx, AllowSideEffects, Info);
11100	}
11101
11102	bool Expr::EvaluateAsFloat(APFloat &Result, const ASTContext &Ctx,
11103	SideEffectsKind AllowSideEffects) const {
11104	if (!getType()->isRealFloatingType())
11105	return false;
11106
11107	EvalResult ExprResult;
11108	if (!EvaluateAsRValue(ExprResult, Ctx) \|\| !ExprResult.Val.isFloat() \|\|
11109	hasUnacceptableSideEffect(ExprResult, AllowSideEffects))
11110	return false;
11111
11112	Result = ExprResult.Val.getFloat();
11113	return true;
11114	}
11115
11116	bool Expr::EvaluateAsLValue(EvalResult &Result, const ASTContext &Ctx) const {
11117	EvalInfo Info(Ctx, Result, EvalInfo::EM_ConstantFold);
11118
11119	LValue LV;
11120	if (!EvaluateLValue(this, LV, Info) \|\| Result.HasSideEffects \|\|
11121	!CheckLValueConstantExpression(Info, getExprLoc(),
11122	Ctx.getLValueReferenceType(getType()), LV,
11123	Expr::EvaluateForCodeGen))
11124	return false;
11125
11126	LV.moveInto(Result.Val);
11127	return true;
11128	}
11129
11130	bool Expr::EvaluateAsConstantExpr(EvalResult &Result, ConstExprUsage Usage,
11131	const ASTContext &Ctx) const {
11132	EvalInfo::EvaluationMode EM = EvalInfo::EM_ConstantExpression;
11133	EvalInfo Info(Ctx, Result, EM);
11134	Info.InConstantContext = true;
11135	if (!::Evaluate(Result.Val, Info, this))
11136	return false;
11137
11138	return CheckConstantExpression(Info, getExprLoc(), getType(), Result.Val,
11139	Usage);
11140	}
11141
11142	bool Expr::EvaluateAsInitializer(APValue &Value, const ASTContext &Ctx,
11143	const VarDecl *VD,
11144	SmallVectorImpl<PartialDiagnosticAt> &Notes) const {
11145	// FIXME: Evaluating initializers for large array and record types can cause
11146	// performance problems. Only do so in C++11 for now.
11147	if (isRValue() && (getType()->isArrayType() \|\| getType()->isRecordType()) &&
11148	!Ctx.getLangOpts().CPlusPlus11)
11149	return false;
11150
11151	Expr::EvalStatus EStatus;
11152	EStatus.Diag = &Notes;
11153
11154	EvalInfo InitInfo(Ctx, EStatus, VD->isConstexpr()
11155	? EvalInfo::EM_ConstantExpression
11156	: EvalInfo::EM_ConstantFold);
11157	InitInfo.setEvaluatingDecl(VD, Value);
11158	InitInfo.InConstantContext = true;
11159
11160	LValue LVal;
11161	LVal.set(VD);
11162
11163	// C++11 [basic.start.init]p2:
11164	// Variables with static storage duration or thread storage duration shall be
11165	// zero-initialized before any other initialization takes place.
11166	// This behavior is not present in C.
11167	if (Ctx.getLangOpts().CPlusPlus && !VD->hasLocalStorage() &&
11168	!VD->getType()->isReferenceType()) {
11169	ImplicitValueInitExpr VIE(VD->getType());
11170	if (!EvaluateInPlace(Value, InitInfo, LVal, &VIE,
11171	/AllowNonLiteralTypes=/true))
11172	return false;
11173	}
11174
11175	if (!EvaluateInPlace(Value, InitInfo, LVal, this,
11176	/AllowNonLiteralTypes=/true) \|\|
11177	EStatus.HasSideEffects)
11178	return false;
11179
11180	return CheckConstantExpression(InitInfo, VD->getLocation(), VD->getType(),
11181	Value);
11182	}
11183
11184	/// isEvaluatable - Call EvaluateAsRValue to see if this expression can be
11185	/// constant folded, but discard the result.
11186	bool Expr::isEvaluatable(const ASTContext &Ctx, SideEffectsKind SEK) const {
11187	EvalResult Result;
11188	return EvaluateAsRValue(Result, Ctx, /* in constant context */ true) &&
11189	!hasUnacceptableSideEffect(Result, SEK);
11190	}
11191
11192	APSInt Expr::EvaluateKnownConstInt(const ASTContext &Ctx,
11193	SmallVectorImpl<PartialDiagnosticAt> *Diag) const {
11194	EvalResult EVResult;
11195	EVResult.Diag = Diag;
11196	EvalInfo Info(Ctx, EVResult, EvalInfo::EM_IgnoreSideEffects);
11197	Info.InConstantContext = true;
11198
11199	bool Result = ::EvaluateAsRValue(this, EVResult, Ctx, Info);
11200	(void)Result;
11201	(0) . __assert_fail ("Result && \"Could not evaluate expression\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 11201, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(Result && "Could not evaluate expression");
11202	(0) . __assert_fail ("EVResult.Val.isInt() && \"Expression did not evaluate to integer\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 11202, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(EVResult.Val.isInt() && "Expression did not evaluate to integer");
11203
11204	return EVResult.Val.getInt();
11205	}
11206
11207	APSInt Expr::EvaluateKnownConstIntCheckOverflow(
11208	const ASTContext &Ctx, SmallVectorImpl<PartialDiagnosticAt> *Diag) const {
11209	EvalResult EVResult;
11210	EVResult.Diag = Diag;
11211	EvalInfo Info(Ctx, EVResult, EvalInfo::EM_EvaluateForOverflow);
11212	Info.InConstantContext = true;
11213
11214	bool Result = ::EvaluateAsRValue(Info, this, EVResult.Val);
11215	(void)Result;
11216	(0) . __assert_fail ("Result && \"Could not evaluate expression\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 11216, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(Result && "Could not evaluate expression");
11217	(0) . __assert_fail ("EVResult.Val.isInt() && \"Expression did not evaluate to integer\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 11217, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(EVResult.Val.isInt() && "Expression did not evaluate to integer");
11218
11219	return EVResult.Val.getInt();
11220	}
11221
11222	void Expr::EvaluateForOverflow(const ASTContext &Ctx) const {
11223	bool IsConst;
11224	EvalResult EVResult;
11225	if (!FastEvaluateAsRValue(this, EVResult, Ctx, IsConst)) {
11226	EvalInfo Info(Ctx, EVResult, EvalInfo::EM_EvaluateForOverflow);
11227	(void)::EvaluateAsRValue(Info, this, EVResult.Val);
11228	}
11229	}
11230
11231	bool Expr::EvalResult::isGlobalLValue() const {
11232	assert(Val.isLValue());
11233	return IsGlobalLValue(Val.getLValueBase());
11234	}
11235
11236
11237	/// isIntegerConstantExpr - this recursive routine will test if an expression is
11238	/// an integer constant expression.
11239
11240	/// FIXME: Pass up a reason why! Invalid operation in i-c-e, division by zero,
11241	/// comma, etc
11242
11243	// CheckICE - This function does the fundamental ICE checking: the returned
11244	// ICEDiag contains an ICEKind indicating whether the expression is an ICE,
11245	// and a (possibly null) SourceLocation indicating the location of the problem.
11246	//
11247	// Note that to reduce code duplication, this helper does no evaluation
11248	// itself; the caller checks whether the expression is evaluatable, and
11249	// in the rare cases where CheckICE actually cares about the evaluated
11250	// value, it calls into Evaluate.
11251
11252	namespace {
11253
11254	enum ICEKind {
11255	/// This expression is an ICE.
11256	IK_ICE,
11257	/// This expression is not an ICE, but if it isn't evaluated, it's
11258	/// a legal subexpression for an ICE. This return value is used to handle
11259	/// the comma operator in C99 mode, and non-constant subexpressions.
11260	IK_ICEIfUnevaluated,
11261	/// This expression is not an ICE, and is not a legal subexpression for one.
11262	IK_NotICE
11263	};
11264
11265	struct ICEDiag {
11266	ICEKind Kind;
11267	SourceLocation Loc;
11268
11269	ICEDiag(ICEKind IK, SourceLocation l) : Kind(IK), Loc(l) {}
11270	};
11271
11272	}
11273
11274	static ICEDiag NoDiag() { return ICEDiag(IK_ICE, SourceLocation()); }
11275
11276	static ICEDiag Worst(ICEDiag A, ICEDiag B) { return A.Kind >= B.Kind ? A : B; }
11277
11278	static ICEDiag CheckEvalInICE(const Expr* E, const ASTContext &Ctx) {
11279	Expr::EvalResult EVResult;
11280	Expr::EvalStatus Status;
11281	EvalInfo Info(Ctx, Status, EvalInfo::EM_ConstantExpression);
11282
11283	Info.InConstantContext = true;
11284	if (!::EvaluateAsRValue(E, EVResult, Ctx, Info) \|\| EVResult.HasSideEffects \|\|
11285	!EVResult.Val.isInt())
11286	return ICEDiag(IK_NotICE, E->getBeginLoc());
11287
11288	return NoDiag();
11289	}
11290
11291	static ICEDiag CheckICE(const Expr* E, const ASTContext &Ctx) {
11292	(0) . __assert_fail ("!E->isValueDependent() && \"Should not see value dependent exprs!\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 11292, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(!E->isValueDependent() && "Should not see value dependent exprs!");
11293	if (!E->getType()->isIntegralOrEnumerationType())
11294	return ICEDiag(IK_NotICE, E->getBeginLoc());
11295
11296	switch (E->getStmtClass()) {
11297	#define ABSTRACT_STMT(Node)
11298	#define STMT(Node, Base) case Expr::Node##Class:
11299	#define EXPR(Node, Base)
11300	#include "clang/AST/StmtNodes.inc"
11301	case Expr::PredefinedExprClass:
11302	case Expr::FloatingLiteralClass:
11303	case Expr::ImaginaryLiteralClass:
11304	case Expr::StringLiteralClass:
11305	case Expr::ArraySubscriptExprClass:
11306	case Expr::OMPArraySectionExprClass:
11307	case Expr::MemberExprClass:
11308	case Expr::CompoundAssignOperatorClass:
11309	case Expr::CompoundLiteralExprClass:
11310	case Expr::ExtVectorElementExprClass:
11311	case Expr::DesignatedInitExprClass:
11312	case Expr::ArrayInitLoopExprClass:
11313	case Expr::ArrayInitIndexExprClass:
11314	case Expr::NoInitExprClass:
11315	case Expr::DesignatedInitUpdateExprClass:
11316	case Expr::ImplicitValueInitExprClass:
11317	case Expr::ParenListExprClass:
11318	case Expr::VAArgExprClass:
11319	case Expr::AddrLabelExprClass:
11320	case Expr::StmtExprClass:
11321	case Expr::CXXMemberCallExprClass:
11322	case Expr::CUDAKernelCallExprClass:
11323	case Expr::CXXDynamicCastExprClass:
11324	case Expr::CXXTypeidExprClass:
11325	case Expr::CXXUuidofExprClass:
11326	case Expr::MSPropertyRefExprClass:
11327	case Expr::MSPropertySubscriptExprClass:
11328	case Expr::CXXNullPtrLiteralExprClass:
11329	case Expr::UserDefinedLiteralClass:
11330	case Expr::CXXThisExprClass:
11331	case Expr::CXXThrowExprClass:
11332	case Expr::CXXNewExprClass:
11333	case Expr::CXXDeleteExprClass:
11334	case Expr::CXXPseudoDestructorExprClass:
11335	case Expr::UnresolvedLookupExprClass:
11336	case Expr::TypoExprClass:
11337	case Expr::DependentScopeDeclRefExprClass:
11338	case Expr::CXXConstructExprClass:
11339	case Expr::CXXInheritedCtorInitExprClass:
11340	case Expr::CXXStdInitializerListExprClass:
11341	case Expr::CXXBindTemporaryExprClass:
11342	case Expr::ExprWithCleanupsClass:
11343	case Expr::CXXTemporaryObjectExprClass:
11344	case Expr::CXXUnresolvedConstructExprClass:
11345	case Expr::CXXDependentScopeMemberExprClass:
11346	case Expr::UnresolvedMemberExprClass:
11347	case Expr::ObjCStringLiteralClass:
11348	case Expr::ObjCBoxedExprClass:
11349	case Expr::ObjCArrayLiteralClass:
11350	case Expr::ObjCDictionaryLiteralClass:
11351	case Expr::ObjCEncodeExprClass:
11352	case Expr::ObjCMessageExprClass:
11353	case Expr::ObjCSelectorExprClass:
11354	case Expr::ObjCProtocolExprClass:
11355	case Expr::ObjCIvarRefExprClass:
11356	case Expr::ObjCPropertyRefExprClass:
11357	case Expr::ObjCSubscriptRefExprClass:
11358	case Expr::ObjCIsaExprClass:
11359	case Expr::ObjCAvailabilityCheckExprClass:
11360	case Expr::ShuffleVectorExprClass:
11361	case Expr::ConvertVectorExprClass:
11362	case Expr::BlockExprClass:
11363	case Expr::NoStmtClass:
11364	case Expr::OpaqueValueExprClass:
11365	case Expr::PackExpansionExprClass:
11366	case Expr::SubstNonTypeTemplateParmPackExprClass:
11367	case Expr::FunctionParmPackExprClass:
11368	case Expr::AsTypeExprClass:
11369	case Expr::ObjCIndirectCopyRestoreExprClass:
11370	case Expr::MaterializeTemporaryExprClass:
11371	case Expr::PseudoObjectExprClass:
11372	case Expr::AtomicExprClass:
11373	case Expr::LambdaExprClass:
11374	case Expr::CXXFoldExprClass:
11375	case Expr::CoawaitExprClass:
11376	case Expr::DependentCoawaitExprClass:
11377	case Expr::CoyieldExprClass:
11378	return ICEDiag(IK_NotICE, E->getBeginLoc());
11379
11380	case Expr::InitListExprClass: {
11381	// C++03 [dcl.init]p13: If T is a scalar type, then a declaration of the
11382	// form "T x = { a };" is equivalent to "T x = a;".
11383	// Unless we're initializing a reference, T is a scalar as it is known to be
11384	// of integral or enumeration type.
11385	if (E->isRValue())
11386	if (cast<InitListExpr>(E)->getNumInits() == 1)
11387	return CheckICE(cast<InitListExpr>(E)->getInit(0), Ctx);
11388	return ICEDiag(IK_NotICE, E->getBeginLoc());
11389	}
11390
11391	case Expr::SizeOfPackExprClass:
11392	case Expr::GNUNullExprClass:
11393	// GCC considers the GNU __null value to be an integral constant expression.
11394	return NoDiag();
11395
11396	case Expr::SubstNonTypeTemplateParmExprClass:
11397	return
11398	CheckICE(cast<SubstNonTypeTemplateParmExpr>(E)->getReplacement(), Ctx);
11399
11400	case Expr::ConstantExprClass:
11401	return CheckICE(cast<ConstantExpr>(E)->getSubExpr(), Ctx);
11402
11403	case Expr::ParenExprClass:
11404	return CheckICE(cast<ParenExpr>(E)->getSubExpr(), Ctx);
11405	case Expr::GenericSelectionExprClass:
11406	return CheckICE(cast<GenericSelectionExpr>(E)->getResultExpr(), Ctx);
11407	case Expr::IntegerLiteralClass:
11408	case Expr::FixedPointLiteralClass:
11409	case Expr::CharacterLiteralClass:
11410	case Expr::ObjCBoolLiteralExprClass:
11411	case Expr::CXXBoolLiteralExprClass:
11412	case Expr::CXXScalarValueInitExprClass:
11413	case Expr::TypeTraitExprClass:
11414	case Expr::ArrayTypeTraitExprClass:
11415	case Expr::ExpressionTraitExprClass:
11416	case Expr::CXXNoexceptExprClass:
11417	return NoDiag();
11418	case Expr::CallExprClass:
11419	case Expr::CXXOperatorCallExprClass: {
11420	// C99 6.6/3 allows function calls within unevaluated subexpressions of
11421	// constant expressions, but they can never be ICEs because an ICE cannot
11422	// contain an operand of (pointer to) function type.
11423	const CallExpr *CE = cast<CallExpr>(E);
11424	if (CE->getBuiltinCallee())
11425	return CheckEvalInICE(E, Ctx);
11426	return ICEDiag(IK_NotICE, E->getBeginLoc());
11427	}
11428	case Expr::DeclRefExprClass: {
11429	if (isa<EnumConstantDecl>(cast<DeclRefExpr>(E)->getDecl()))
11430	return NoDiag();
11431	const ValueDecl *D = cast<DeclRefExpr>(E)->getDecl();
11432	if (Ctx.getLangOpts().CPlusPlus &&
11433	D && IsConstNonVolatile(D->getType())) {
11434	// Parameter variables are never constants. Without this check,
11435	// getAnyInitializer() can find a default argument, which leads
11436	// to chaos.
11437	if (isa<ParmVarDecl>(D))
11438	return ICEDiag(IK_NotICE, cast<DeclRefExpr>(E)->getLocation());
11439
11440	// C++ 7.1.5.1p2
11441	// A variable of non-volatile const-qualified integral or enumeration
11442	// type initialized by an ICE can be used in ICEs.
11443	if (const VarDecl *Dcl = dyn_cast<VarDecl>(D)) {
11444	if (!Dcl->getType()->isIntegralOrEnumerationType())
11445	return ICEDiag(IK_NotICE, cast<DeclRefExpr>(E)->getLocation());
11446
11447	const VarDecl *VD;
11448	// Look for a declaration of this variable that has an initializer, and
11449	// check whether it is an ICE.
11450	if (Dcl->getAnyInitializer(VD) && VD->checkInitIsICE())
11451	return NoDiag();
11452	else
11453	return ICEDiag(IK_NotICE, cast<DeclRefExpr>(E)->getLocation());
11454	}
11455	}
11456	return ICEDiag(IK_NotICE, E->getBeginLoc());
11457	}
11458	case Expr::UnaryOperatorClass: {
11459	const UnaryOperator *Exp = cast<UnaryOperator>(E);
11460	switch (Exp->getOpcode()) {
11461	case UO_PostInc:
11462	case UO_PostDec:
11463	case UO_PreInc:
11464	case UO_PreDec:
11465	case UO_AddrOf:
11466	case UO_Deref:
11467	case UO_Coawait:
11468	// C99 6.6/3 allows increment and decrement within unevaluated
11469	// subexpressions of constant expressions, but they can never be ICEs
11470	// because an ICE cannot contain an lvalue operand.
11471	return ICEDiag(IK_NotICE, E->getBeginLoc());
11472	case UO_Extension:
11473	case UO_LNot:
11474	case UO_Plus:
11475	case UO_Minus:
11476	case UO_Not:
11477	case UO_Real:
11478	case UO_Imag:
11479	return CheckICE(Exp->getSubExpr(), Ctx);
11480	}
11481	llvm_unreachable("invalid unary operator class");
11482	}
11483	case Expr::OffsetOfExprClass: {
11484	// Note that per C99, offsetof must be an ICE. And AFAIK, using
11485	// EvaluateAsRValue matches the proposed gcc behavior for cases like
11486	// "offsetof(struct s{int x[4];}, x[1.0])". This doesn't affect
11487	// compliance: we should warn earlier for offsetof expressions with
11488	// array subscripts that aren't ICEs, and if the array subscripts
11489	// are ICEs, the value of the offsetof must be an integer constant.
11490	return CheckEvalInICE(E, Ctx);
11491	}
11492	case Expr::UnaryExprOrTypeTraitExprClass: {
11493	const UnaryExprOrTypeTraitExpr *Exp = cast<UnaryExprOrTypeTraitExpr>(E);
11494	if ((Exp->getKind() == UETT_SizeOf) &&
11495	Exp->getTypeOfArgument()->isVariableArrayType())
11496	return ICEDiag(IK_NotICE, E->getBeginLoc());
11497	return NoDiag();
11498	}
11499	case Expr::BinaryOperatorClass: {
11500	const BinaryOperator *Exp = cast<BinaryOperator>(E);
11501	switch (Exp->getOpcode()) {
11502	case BO_PtrMemD:
11503	case BO_PtrMemI:
11504	case BO_Assign:
11505	case BO_MulAssign:
11506	case BO_DivAssign:
11507	case BO_RemAssign:
11508	case BO_AddAssign:
11509	case BO_SubAssign:
11510	case BO_ShlAssign:
11511	case BO_ShrAssign:
11512	case BO_AndAssign:
11513	case BO_XorAssign:
11514	case BO_OrAssign:
11515	// C99 6.6/3 allows assignments within unevaluated subexpressions of
11516	// constant expressions, but they can never be ICEs because an ICE cannot
11517	// contain an lvalue operand.
11518	return ICEDiag(IK_NotICE, E->getBeginLoc());
11519
11520	case BO_Mul:
11521	case BO_Div:
11522	case BO_Rem:
11523	case BO_Add:
11524	case BO_Sub:
11525	case BO_Shl:
11526	case BO_Shr:
11527	case BO_LT:
11528	case BO_GT:
11529	case BO_LE:
11530	case BO_GE:
11531	case BO_EQ:
11532	case BO_NE:
11533	case BO_And:
11534	case BO_Xor:
11535	case BO_Or:
11536	case BO_Comma:
11537	case BO_Cmp: {
11538	ICEDiag LHSResult = CheckICE(Exp->getLHS(), Ctx);
11539	ICEDiag RHSResult = CheckICE(Exp->getRHS(), Ctx);
11540	if (Exp->getOpcode() == BO_Div \|\|
11541	Exp->getOpcode() == BO_Rem) {
11542	// EvaluateAsRValue gives an error for undefined Div/Rem, so make sure
11543	// we don't evaluate one.
11544	if (LHSResult.Kind == IK_ICE && RHSResult.Kind == IK_ICE) {
11545	llvm::APSInt REval = Exp->getRHS()->EvaluateKnownConstInt(Ctx);
11546	if (REval == 0)
11547	return ICEDiag(IK_ICEIfUnevaluated, E->getBeginLoc());
11548	if (REval.isSigned() && REval.isAllOnesValue()) {
11549	llvm::APSInt LEval = Exp->getLHS()->EvaluateKnownConstInt(Ctx);
11550	if (LEval.isMinSignedValue())
11551	return ICEDiag(IK_ICEIfUnevaluated, E->getBeginLoc());
11552	}
11553	}
11554	}
11555	if (Exp->getOpcode() == BO_Comma) {
11556	if (Ctx.getLangOpts().C99) {
11557	// C99 6.6p3 introduces a strange edge case: comma can be in an ICE
11558	// if it isn't evaluated.
11559	if (LHSResult.Kind == IK_ICE && RHSResult.Kind == IK_ICE)
11560	return ICEDiag(IK_ICEIfUnevaluated, E->getBeginLoc());
11561	} else {
11562	// In both C89 and C++, commas in ICEs are illegal.
11563	return ICEDiag(IK_NotICE, E->getBeginLoc());
11564	}
11565	}
11566	return Worst(LHSResult, RHSResult);
11567	}
11568	case BO_LAnd:
11569	case BO_LOr: {
11570	ICEDiag LHSResult = CheckICE(Exp->getLHS(), Ctx);
11571	ICEDiag RHSResult = CheckICE(Exp->getRHS(), Ctx);
11572	if (LHSResult.Kind == IK_ICE && RHSResult.Kind == IK_ICEIfUnevaluated) {
11573	// Rare case where the RHS has a comma "side-effect"; we need
11574	// to actually check the condition to see whether the side
11575	// with the comma is evaluated.
11576	if ((Exp->getOpcode() == BO_LAnd) !=
11577	(Exp->getLHS()->EvaluateKnownConstInt(Ctx) == 0))
11578	return RHSResult;
11579	return NoDiag();
11580	}
11581
11582	return Worst(LHSResult, RHSResult);
11583	}
11584	}
11585	llvm_unreachable("invalid binary operator kind");
11586	}
11587	case Expr::ImplicitCastExprClass:
11588	case Expr::CStyleCastExprClass:
11589	case Expr::CXXFunctionalCastExprClass:
11590	case Expr::CXXStaticCastExprClass:
11591	case Expr::CXXReinterpretCastExprClass:
11592	case Expr::CXXConstCastExprClass:
11593	case Expr::ObjCBridgedCastExprClass: {
11594	const Expr *SubExpr = cast<CastExpr>(E)->getSubExpr();
11595	if (isa<ExplicitCastExpr>(E)) {
11596	if (const FloatingLiteral *FL
11597	= dyn_cast<FloatingLiteral>(SubExpr->IgnoreParenImpCasts())) {
11598	unsigned DestWidth = Ctx.getIntWidth(E->getType());
11599	bool DestSigned = E->getType()->isSignedIntegerOrEnumerationType();
11600	APSInt IgnoredVal(DestWidth, !DestSigned);
11601	bool Ignored;
11602	// If the value does not fit in the destination type, the behavior is
11603	// undefined, so we are not required to treat it as a constant
11604	// expression.
11605	if (FL->getValue().convertToInteger(IgnoredVal,
11606	llvm::APFloat::rmTowardZero,
11607	&Ignored) & APFloat::opInvalidOp)
11608	return ICEDiag(IK_NotICE, E->getBeginLoc());
11609	return NoDiag();
11610	}
11611	}
11612	switch (cast<CastExpr>(E)->getCastKind()) {
11613	case CK_LValueToRValue:
11614	case CK_AtomicToNonAtomic:
11615	case CK_NonAtomicToAtomic:
11616	case CK_NoOp:
11617	case CK_IntegralToBoolean:
11618	case CK_IntegralCast:
11619	return CheckICE(SubExpr, Ctx);
11620	default:
11621	return ICEDiag(IK_NotICE, E->getBeginLoc());
11622	}
11623	}
11624	case Expr::BinaryConditionalOperatorClass: {
11625	const BinaryConditionalOperator *Exp = cast<BinaryConditionalOperator>(E);
11626	ICEDiag CommonResult = CheckICE(Exp->getCommon(), Ctx);
11627	if (CommonResult.Kind == IK_NotICE) return CommonResult;
11628	ICEDiag FalseResult = CheckICE(Exp->getFalseExpr(), Ctx);
11629	if (FalseResult.Kind == IK_NotICE) return FalseResult;
11630	if (CommonResult.Kind == IK_ICEIfUnevaluated) return CommonResult;
11631	if (FalseResult.Kind == IK_ICEIfUnevaluated &&
11632	Exp->getCommon()->EvaluateKnownConstInt(Ctx) != 0) return NoDiag();
11633	return FalseResult;
11634	}
11635	case Expr::ConditionalOperatorClass: {
11636	const ConditionalOperator *Exp = cast<ConditionalOperator>(E);
11637	// If the condition (ignoring parens) is a __builtin_constant_p call,
11638	// then only the true side is actually considered in an integer constant
11639	// expression, and it is fully evaluated. This is an important GNU
11640	// extension. See GCC PR38377 for discussion.
11641	if (const CallExpr *CallCE
11642	= dyn_cast<CallExpr>(Exp->getCond()->IgnoreParenCasts()))
11643	if (CallCE->getBuiltinCallee() == Builtin::BI__builtin_constant_p)
11644	return CheckEvalInICE(E, Ctx);
11645	ICEDiag CondResult = CheckICE(Exp->getCond(), Ctx);
11646	if (CondResult.Kind == IK_NotICE)
11647	return CondResult;
11648
11649	ICEDiag TrueResult = CheckICE(Exp->getTrueExpr(), Ctx);
11650	ICEDiag FalseResult = CheckICE(Exp->getFalseExpr(), Ctx);
11651
11652	if (TrueResult.Kind == IK_NotICE)
11653	return TrueResult;
11654	if (FalseResult.Kind == IK_NotICE)
11655	return FalseResult;
11656	if (CondResult.Kind == IK_ICEIfUnevaluated)
11657	return CondResult;
11658	if (TrueResult.Kind == IK_ICE && FalseResult.Kind == IK_ICE)
11659	return NoDiag();
11660	// Rare case where the diagnostics depend on which side is evaluated
11661	// Note that if we get here, CondResult is 0, and at least one of
11662	// TrueResult and FalseResult is non-zero.
11663	if (Exp->getCond()->EvaluateKnownConstInt(Ctx) == 0)
11664	return FalseResult;
11665	return TrueResult;
11666	}
11667	case Expr::CXXDefaultArgExprClass:
11668	return CheckICE(cast<CXXDefaultArgExpr>(E)->getExpr(), Ctx);
11669	case Expr::CXXDefaultInitExprClass:
11670	return CheckICE(cast<CXXDefaultInitExpr>(E)->getExpr(), Ctx);
11671	case Expr::ChooseExprClass: {
11672	return CheckICE(cast<ChooseExpr>(E)->getChosenSubExpr(), Ctx);
11673	}
11674	}
11675
11676	llvm_unreachable("Invalid StmtClass!");
11677	}
11678
11679	/// Evaluate an expression as a C++11 integral constant expression.
11680	static bool EvaluateCPlusPlus11IntegralConstantExpr(const ASTContext &Ctx,
11681	const Expr *E,
11682	llvm::APSInt *Value,
11683	SourceLocation *Loc) {
11684	if (!E->getType()->isIntegralOrUnscopedEnumerationType()) {
11685	if (Loc) *Loc = E->getExprLoc();
11686	return false;
11687	}
11688
11689	APValue Result;
11690	if (!E->isCXX11ConstantExpr(Ctx, &Result, Loc))
11691	return false;
11692
11693	if (!Result.isInt()) {
11694	if (Loc) *Loc = E->getExprLoc();
11695	return false;
11696	}
11697
11698	if (Value) *Value = Result.getInt();
11699	return true;
11700	}
11701
11702	bool Expr::isIntegerConstantExpr(const ASTContext &Ctx,
11703	SourceLocation *Loc) const {
11704	if (Ctx.getLangOpts().CPlusPlus11)
11705	return EvaluateCPlusPlus11IntegralConstantExpr(Ctx, this, nullptr, Loc);
11706
11707	ICEDiag D = CheckICE(this, Ctx);
11708	if (D.Kind != IK_ICE) {
11709	if (Loc) *Loc = D.Loc;
11710	return false;
11711	}
11712	return true;
11713	}
11714
11715	bool Expr::isIntegerConstantExpr(llvm::APSInt &Value, const ASTContext &Ctx,
11716	SourceLocation *Loc, bool isEvaluated) const {
11717	if (Ctx.getLangOpts().CPlusPlus11)
11718	return EvaluateCPlusPlus11IntegralConstantExpr(Ctx, this, &Value, Loc);
11719
11720	if (!isIntegerConstantExpr(Ctx, Loc))
11721	return false;
11722
11723	// The only possible side-effects here are due to UB discovered in the
11724	// evaluation (for instance, INT_MAX + 1). In such a case, we are still
11725	// required to treat the expression as an ICE, so we produce the folded
11726	// value.
11727	EvalResult ExprResult;
11728	Expr::EvalStatus Status;
11729	EvalInfo Info(Ctx, Status, EvalInfo::EM_IgnoreSideEffects);
11730	Info.InConstantContext = true;
11731
11732	if (!::EvaluateAsInt(this, ExprResult, Ctx, SE_AllowSideEffects, Info))
11733	llvm_unreachable("ICE cannot be evaluated!");
11734
11735	Value = ExprResult.Val.getInt();
11736	return true;
11737	}
11738
11739	bool Expr::isCXX98IntegralConstantExpr(const ASTContext &Ctx) const {
11740	return CheckICE(this, Ctx).Kind == IK_ICE;
11741	}
11742
11743	bool Expr::isCXX11ConstantExpr(const ASTContext &Ctx, APValue *Result,
11744	SourceLocation *Loc) const {
11745	// We support this checking in C++98 mode in order to diagnose compatibility
11746	// issues.
11747	assert(Ctx.getLangOpts().CPlusPlus);
11748
11749	// Build evaluation settings.
11750	Expr::EvalStatus Status;
11751	SmallVector<PartialDiagnosticAt, 8> Diags;
11752	Status.Diag = &Diags;
11753	EvalInfo Info(Ctx, Status, EvalInfo::EM_ConstantExpression);
11754
11755	APValue Scratch;
11756	bool IsConstExpr = ::EvaluateAsRValue(Info, this, Result ? *Result : Scratch);
11757
11758	if (!Diags.empty()) {
11759	IsConstExpr = false;
11760	if (Loc) *Loc = Diags[0].first;
11761	} else if (!IsConstExpr) {
11762	// FIXME: This shouldn't happen.
11763	if (Loc) *Loc = getExprLoc();
11764	}
11765
11766	return IsConstExpr;
11767	}
11768
11769	bool Expr::EvaluateWithSubstitution(APValue &Value, ASTContext &Ctx,
11770	const FunctionDecl *Callee,
11771	ArrayRef<const Expr*> Args,
11772	const Expr *This) const {
11773	Expr::EvalStatus Status;
11774	EvalInfo Info(Ctx, Status, EvalInfo::EM_ConstantExpressionUnevaluated);
11775	Info.InConstantContext = true;
11776
11777	LValue ThisVal;
11778	const LValue *ThisPtr = nullptr;
11779	if (This) {
11780	#ifndef NDEBUG
11781	auto *MD = dyn_cast<CXXMethodDecl>(Callee);
11782	(0) . __assert_fail ("MD && \"Don't provide `this` for non-methods.\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 11782, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(MD && "Don't provide `this` for non-methods.");
11783	(0) . __assert_fail ("!MD->isStatic() && \"Don't provide `this` for static methods.\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 11783, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(!MD->isStatic() && "Don't provide `this` for static methods.");
11784	#endif
11785	if (EvaluateObjectArgument(Info, This, ThisVal))
11786	ThisPtr = &ThisVal;
11787	if (Info.EvalStatus.HasSideEffects)
11788	return false;
11789	}
11790
11791	ArgVector ArgValues(Args.size());
11792	for (ArrayRef<const Expr*>::iterator I = Args.begin(), E = Args.end();
11793	I != E; ++I) {
11794	if ((*I)->isValueDependent() \|\|
11795	!Evaluate(ArgValues[I - Args.begin()], Info, *I))
11796	// If evaluation fails, throw away the argument entirely.
11797	ArgValues[I - Args.begin()] = APValue();
11798	if (Info.EvalStatus.HasSideEffects)
11799	return false;
11800	}
11801
11802	// Build fake call to Callee.
11803	CallStackFrame Frame(Info, Callee->getLocation(), Callee, ThisPtr,
11804	ArgValues.data());
11805	return Evaluate(Value, Info, this) && !Info.EvalStatus.HasSideEffects;
11806	}
11807
11808	bool Expr::isPotentialConstantExpr(const FunctionDecl *FD,
11809	SmallVectorImpl<
11810	PartialDiagnosticAt> &Diags) {
11811	// FIXME: It would be useful to check constexpr function templates, but at the
11812	// moment the constant expression evaluator cannot cope with the non-rigorous
11813	// ASTs which we build for dependent expressions.
11814	if (FD->isDependentContext())
11815	return true;
11816
11817	Expr::EvalStatus Status;
11818	Status.Diag = &Diags;
11819
11820	EvalInfo Info(FD->getASTContext(), Status,
11821	EvalInfo::EM_PotentialConstantExpression);
11822	Info.InConstantContext = true;
11823
11824	const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD);
11825	const CXXRecordDecl *RD = MD ? MD->getParent()->getCanonicalDecl() : nullptr;
11826
11827	// Fabricate an arbitrary expression on the stack and pretend that it
11828	// is a temporary being used as the 'this' pointer.
11829	LValue This;
11830	ImplicitValueInitExpr VIE(RD ? Info.Ctx.getRecordType(RD) : Info.Ctx.IntTy);
11831	This.set({&VIE, Info.CurrentCall->Index});
11832
11833	ArrayRef<const Expr*> Args;
11834
11835	APValue Scratch;
11836	if (const CXXConstructorDecl *CD = dyn_cast<CXXConstructorDecl>(FD)) {
11837	// Evaluate the call as a constant initializer, to allow the construction
11838	// of objects of non-literal types.
11839	Info.setEvaluatingDecl(This.getLValueBase(), Scratch);
11840	HandleConstructorCall(&VIE, This, Args, CD, Info, Scratch);
11841	} else {
11842	SourceLocation Loc = FD->getLocation();
11843	HandleFunctionCall(Loc, FD, (MD && MD->isInstance()) ? &This : nullptr,
11844	Args, FD->getBody(), Info, Scratch, nullptr);
11845	}
11846
11847	return Diags.empty();
11848	}
11849
11850	bool Expr::isPotentialConstantExprUnevaluated(Expr *E,
11851	const FunctionDecl *FD,
11852	SmallVectorImpl<
11853	PartialDiagnosticAt> &Diags) {
11854	Expr::EvalStatus Status;
11855	Status.Diag = &Diags;
11856
11857	EvalInfo Info(FD->getASTContext(), Status,
11858	EvalInfo::EM_PotentialConstantExpressionUnevaluated);
11859	Info.InConstantContext = true;
11860
11861	// Fabricate a call stack frame to give the arguments a plausible cover story.
11862	ArrayRef<const Expr*> Args;
11863	ArgVector ArgValues(0);
11864	bool Success = EvaluateArgs(Args, ArgValues, Info);
11865	(void)Success;
11866	(0) . __assert_fail ("Success && \"Failed to set up arguments for potential constant evaluation\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 11867, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(Success &&
11867	(0) . __assert_fail ("Success && \"Failed to set up arguments for potential constant evaluation\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/ExprConstant.cpp", 11867, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true"> "Failed to set up arguments for potential constant evaluation");
11868	CallStackFrame Frame(Info, SourceLocation(), FD, nullptr, ArgValues.data());
11869
11870	APValue ResultScratch;
11871	Evaluate(ResultScratch, Info, E);
11872	return Diags.empty();
11873	}
11874
11875	bool Expr::tryEvaluateObjectSize(uint64_t &Result, ASTContext &Ctx,
11876	unsigned Type) const {
11877	if (!getType()->isPointerType())
11878	return false;
11879
11880	Expr::EvalStatus Status;
11881	EvalInfo Info(Ctx, Status, EvalInfo::EM_ConstantFold);
11882	return tryEvaluateBuiltinObjectSize(this, Type, Info, Result);
11883	}
11884

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