From 703e488ed9229ac50a54c69f207074e7ec0715bd Mon Sep 17 00:00:00 2001 From: Nick Lewycky Date: Mon, 14 Jul 2014 18:52:02 +0000 Subject: Don't eliminate memcpy's when the address of the pointer may itself be relevant. Fixes PR18304. Patch by David Wiberg! llvm-svn: 212970 --- llvm/test/Transforms/MemCpyOpt/capturing-func.ll | 22 ++++++++++++++++++++++ 1 file changed, 22 insertions(+) create mode 100644 llvm/test/Transforms/MemCpyOpt/capturing-func.ll (limited to 'llvm/test/Transforms/MemCpyOpt/capturing-func.ll') diff --git a/llvm/test/Transforms/MemCpyOpt/capturing-func.ll b/llvm/test/Transforms/MemCpyOpt/capturing-func.ll new file mode 100644 index 00000000000..17614fd181d --- /dev/null +++ b/llvm/test/Transforms/MemCpyOpt/capturing-func.ll @@ -0,0 +1,22 @@ +; RUN: opt < %s -basicaa -memcpyopt -S | FileCheck %s + +target datalayout = "e" + +declare void @foo(i8*) +declare void @llvm.memcpy.p0i8.p0i8.i32(i8* nocapture, i8* nocapture, i32, i32, i1) nounwind + +define void @test() { + %ptr1 = alloca i8 + %ptr2 = alloca i8 + call void @foo(i8* %ptr2) + call void @llvm.memcpy.p0i8.p0i8.i32(i8* %ptr1, i8* %ptr2, i32 1, i32 1, i1 false) + call void @foo(i8* %ptr1) + ret void + + ; Check that the transformation isn't applied if the called function can + ; capture the pointer argument (i.e. the nocapture attribute isn't present) + ; CHECK-LABEL: @test( + ; CHECK: call void @foo(i8* %ptr2) + ; CHECK-NEXT: call void @llvm.memcpy + ; CHECK-NEXT: call void @foo(i8* %ptr1) +} -- cgit v1.2.3