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