Transforms.h source code [clang_source_code/lib/ARCMigrate/Transforms.h]

1	//===-- Transforms.h - Transformations to ARC mode --------------- C++ --===//
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	#ifndef LLVM_CLANG_LIB_ARCMIGRATE_TRANSFORMS_H
10	#define LLVM_CLANG_LIB_ARCMIGRATE_TRANSFORMS_H
11
12	#include "clang/AST/ParentMap.h"
13	#include "clang/AST/RecursiveASTVisitor.h"
14	#include "llvm/ADT/DenseSet.h"
15	#include "llvm/Support/SaveAndRestore.h"
16
17	namespace clang {
18	class Decl;
19	class Stmt;
20	class BlockDecl;
21	class ObjCMethodDecl;
22	class FunctionDecl;
23
24	namespace arcmt {
25	class MigrationPass;
26
27	namespace trans {
28
29	class MigrationContext;
30
31	//===----------------------------------------------------------------------===//
32	// Transformations.
33	//===----------------------------------------------------------------------===//
34
35	void rewriteAutoreleasePool(MigrationPass &pass);
36	void rewriteUnbridgedCasts(MigrationPass &pass);
37	void makeAssignARCSafe(MigrationPass &pass);
38	void removeRetainReleaseDeallocFinalize(MigrationPass &pass);
39	void removeZeroOutPropsInDeallocFinalize(MigrationPass &pass);
40	void rewriteUnusedInitDelegate(MigrationPass &pass);
41	void checkAPIUses(MigrationPass &pass);
42
43	void removeEmptyStatementsAndDeallocFinalize(MigrationPass &pass);
44
45	class BodyContext {
46	MigrationContext &MigrateCtx;
47	ParentMap PMap;
48	Stmt *TopStmt;
49
50	public:
51	BodyContext(MigrationContext &MigrateCtx, Stmt *S)
52	: MigrateCtx(MigrateCtx), PMap(S), TopStmt(S) {}
53
54	MigrationContext &getMigrationContext() { return MigrateCtx; }
55	ParentMap &getParentMap() { return PMap; }
56	Stmt *getTopStmt() { return TopStmt; }
57	};
58
59	class ObjCImplementationContext {
60	MigrationContext &MigrateCtx;
61	ObjCImplementationDecl *ImpD;
62
63	public:
64	ObjCImplementationContext(MigrationContext &MigrateCtx,
65	ObjCImplementationDecl *D)
66	: MigrateCtx(MigrateCtx), ImpD(D) {}
67
68	MigrationContext &getMigrationContext() { return MigrateCtx; }
69	ObjCImplementationDecl *getImplementationDecl() { return ImpD; }
70	};
71
72	class ASTTraverser {
73	public:
74	virtual ~ASTTraverser();
75	virtual void traverseTU(MigrationContext &MigrateCtx) { }
76	virtual void traverseBody(BodyContext &BodyCtx) { }
77	virtual void traverseObjCImplementation(ObjCImplementationContext &ImplCtx) {}
78	};
79
80	class MigrationContext {
81	std::vector<ASTTraverser *> Traversers;
82
83	public:
84	MigrationPass &Pass;
85
86	struct GCAttrOccurrence {
87	enum AttrKind { Weak, Strong } Kind;
88	SourceLocation Loc;
89	QualType ModifiedType;
90	Decl *Dcl;
91	/// true if the attribute is owned, e.g. it is in a body and not just
92	/// in an interface.
93	bool FullyMigratable;
94	};
95	std::vector<GCAttrOccurrence> GCAttrs;
96	llvm::DenseSet<unsigned> AttrSet;
97	llvm::DenseSet<unsigned> RemovedAttrSet;
98
99	/// Set of raw '@' locations for 'assign' properties group that contain
100	/// GC __weak.
101	llvm::DenseSet<unsigned> AtPropsWeak;
102
103	explicit MigrationContext(MigrationPass &pass) : Pass(pass) {}
104	~MigrationContext();
105
106	typedef std::vector<ASTTraverser *>::iterator traverser_iterator;
107	traverser_iterator traversers_begin() { return Traversers.begin(); }
108	traverser_iterator traversers_end() { return Traversers.end(); }
109
110	void addTraverser(ASTTraverser *traverser) {
111	Traversers.push_back(traverser);
112	}
113
114	bool isGCOwnedNonObjC(QualType T);
115	bool removePropertyAttribute(StringRef fromAttr, SourceLocation atLoc) {
116	return rewritePropertyAttribute(fromAttr, StringRef(), atLoc);
117	}
118	bool rewritePropertyAttribute(StringRef fromAttr, StringRef toAttr,
119	SourceLocation atLoc);
120	bool addPropertyAttribute(StringRef attr, SourceLocation atLoc);
121
122	void traverse(TranslationUnitDecl *TU);
123
124	void dumpGCAttrs();
125	};
126
127	class PropertyRewriteTraverser : public ASTTraverser {
128	public:
129	void traverseObjCImplementation(ObjCImplementationContext &ImplCtx) override;
130	};
131
132	class BlockObjCVariableTraverser : public ASTTraverser {
133	public:
134	void traverseBody(BodyContext &BodyCtx) override;
135	};
136
137	class ProtectedScopeTraverser : public ASTTraverser {
138	public:
139	void traverseBody(BodyContext &BodyCtx) override;
140	};
141
142	// GC transformations
143
144	class GCAttrsTraverser : public ASTTraverser {
145	public:
146	void traverseTU(MigrationContext &MigrateCtx) override;
147	};
148
149	class GCCollectableCallsTraverser : public ASTTraverser {
150	public:
151	void traverseBody(BodyContext &BodyCtx) override;
152	};
153
154	//===----------------------------------------------------------------------===//
155	// Helpers.
156	//===----------------------------------------------------------------------===//
157
158	/// Determine whether we can add weak to the given type.
159	bool canApplyWeak(ASTContext &Ctx, QualType type,
160	bool AllowOnUnknownClass = false);
161
162	bool isPlusOneAssign(const BinaryOperator *E);
163	bool isPlusOne(const Expr *E);
164
165	/// 'Loc' is the end of a statement range. This returns the location
166	/// immediately after the semicolon following the statement.
167	/// If no semicolon is found or the location is inside a macro, the returned
168	/// source location will be invalid.
169	SourceLocation findLocationAfterSemi(SourceLocation loc, ASTContext &Ctx,
170	bool IsDecl = false);
171
172	/// 'Loc' is the end of a statement range. This returns the location
173	/// of the semicolon following the statement.
174	/// If no semicolon is found or the location is inside a macro, the returned
175	/// source location will be invalid.
176	SourceLocation findSemiAfterLocation(SourceLocation loc, ASTContext &Ctx,
177	bool IsDecl = false);
178
179	bool hasSideEffects(Expr *E, ASTContext &Ctx);
180	bool isGlobalVar(Expr *E);
181	/// Returns "nil" or "0" if 'nil' macro is not actually defined.
182	StringRef getNilString(MigrationPass &Pass);
183
184	template <typename BODY_TRANS>
185	class BodyTransform : public RecursiveASTVisitor<BodyTransform<BODY_TRANS> > {
186	MigrationPass &Pass;
187	Decl *ParentD;
188
189	typedef RecursiveASTVisitor<BodyTransform<BODY_TRANS> > base;
190	public:
191	BodyTransform(MigrationPass &pass) : Pass(pass), ParentD(nullptr) { }
192
193	bool TraverseStmt(Stmt *rootS) {
194	if (rootS)
195	BODY_TRANS(Pass).transformBody(rootS, ParentD);
196	return true;
197	}
198
199	bool TraverseObjCMethodDecl(ObjCMethodDecl *D) {
200	SaveAndRestore<Decl *> SetParent(ParentD, D);
201	return base::TraverseObjCMethodDecl(D);
202	}
203	};
204
205	typedef llvm::DenseSet<Expr *> ExprSet;
206
207	void clearRefsIn(Stmt *S, ExprSet &refs);
208	template <typename iterator>
209	void clearRefsIn(iterator begin, iterator end, ExprSet &refs) {
210	for (; begin != end; ++begin)
211	clearRefsIn(*begin, refs);
212	}
213
214	void collectRefs(ValueDecl D, Stmt S, ExprSet &refs);
215
216	void collectRemovables(Stmt *S, ExprSet &exprs);
217
218	} // end namespace trans
219
220	} // end namespace arcmt
221
222	} // end namespace clang
223
224	#endif
225