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| author | Dan Gohman <gohman@apple.com> | 2009-11-09 19:29:11 +0000 |
|---|---|---|
| committer | Dan Gohman <gohman@apple.com> | 2009-11-09 19:29:11 +0000 |
| commit | ccb4584eddd133ff90fc0e19929c8ce4089a33ae (patch) | |
| tree | d8871bec5abdc9646dec5704d087c5f7cc9be5b0 /llvm/test/Transforms/GVN/null-aliases-nothing.ll | |
| parent | 1bc688dc6029ffc6975378d95f6f6d95051b1c11 (diff) | |
| download | bcm5719-llvm-ccb4584eddd133ff90fc0e19929c8ce4089a33ae.tar.gz bcm5719-llvm-ccb4584eddd133ff90fc0e19929c8ce4089a33ae.zip | |
Default-addressspace null pointers don't alias anything. This allows
GVN to be more aggressive. Patch by Hans Wennborg! (with a comment added by me)
llvm-svn: 86582
Diffstat (limited to 'llvm/test/Transforms/GVN/null-aliases-nothing.ll')
| -rw-r--r-- | llvm/test/Transforms/GVN/null-aliases-nothing.ll | 20 |
1 files changed, 20 insertions, 0 deletions
diff --git a/llvm/test/Transforms/GVN/null-aliases-nothing.ll b/llvm/test/Transforms/GVN/null-aliases-nothing.ll new file mode 100644 index 00000000000..bc5c850e5f2 --- /dev/null +++ b/llvm/test/Transforms/GVN/null-aliases-nothing.ll @@ -0,0 +1,20 @@ +; RUN: opt %s -gvn -S | FileCheck %s + +%t = type { i32 } +declare void @test1f(i8*) + +define void @test1(%t* noalias %stuff ) { + %p = getelementptr inbounds %t* %stuff, i32 0, i32 0 + %before = load i32* %p + + call void @test1f(i8* null) + + %after = load i32* %p ; <--- This should be a dead load + %sum = add i32 %before, %after; + + store i32 %sum, i32* %p + ret void +; CHECK: load +; CHECK-NOT: load +; CHECK: ret void +} |

