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1// RUN: %clang_cc1 -triple x86_64-unknown-unknown -emit-llvm -o - %s | FileCheck %s2 3// It could hit in @llvm.memcpy with "-triple x86_64-(mingw32|win32)".4// CHECK-NOT: readonly5// CHECK-NOT: readnone6 7// The struct being passed byval means that we cannot mark the8// function readnone. Readnone would allow stores to the arg to9// be deleted in the caller. We also don't allow readonly since10// the callee might write to the byval parameter. The inliner11// would have to assume the worse and introduce an explicit12// temporary when inlining such a function, which is costly for13// the common case in which the byval argument is not written.14struct S { int A[1000]; };15int __attribute__ ((const)) f(struct S x) { x.A[1] = 0; return x.A[0]; }16int g(struct S x) __attribute__ ((pure));17int h(struct S x) { return g(x); }18