| 1 | // RUN: %clang_cc1 -triple x86_64-unknown-unknown -emit-llvm -o - %s | FileCheck %s |
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| 2 | |
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| 3 | // It could hit in @llvm.memcpy with "-triple x86_64-(mingw32|win32)". |
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| 4 | // CHECK-NOT: readonly |
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| 5 | // CHECK-NOT: readnone |
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| 6 | |
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| 7 | // The struct being passed byval means that we cannot mark the |
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| 8 | // function readnone. Readnone would allow stores to the arg to |
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| 9 | // be deleted in the caller. We also don't allow readonly since |
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| 10 | // the callee might write to the byval parameter. The inliner |
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| 11 | // would have to assume the worse and introduce an explicit |
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| 12 | // temporary when inlining such a function, which is costly for |
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| 13 | // the common case in which the byval argument is not written. |
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| 14 | struct S { int A[1000]; }; |
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| 15 | int __attribute__ ((const)) f(struct S x) { x.A[1] = 0; return x.A[0]; } |
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| 16 | int g(struct S x) __attribute__ ((pure)); |
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| 17 | int h(struct S x) { return g(x); } |
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| 18 | |
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