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| author | Dan Gohman <gohman@apple.com> | 2009-09-14 23:39:10 +0000 |
|---|---|---|
| committer | Dan Gohman <gohman@apple.com> | 2009-09-14 23:39:10 +0000 |
| commit | 264d245851173bbace9281a2378a6cc51162b030 (patch) | |
| tree | dabb1141b0c57693d16f4653eb6c7232320cb3bb | |
| parent | 46262684285cd7baf74425610228ac8b4547dab1 (diff) | |
When extending a memset range past the front, set the alignment of the
memset region to the alignment of the new start address.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@81810 91177308-0d34-0410-b5e6-96231b3b80d8
| -rw-r--r-- | lib/Transforms/Scalar/MemCpyOptimizer.cpp | 1 | ||||
| -rw-r--r-- | test/Transforms/MemCpyOpt/align.ll | 18 |
2 files changed, 19 insertions, 0 deletions
diff --git a/lib/Transforms/Scalar/MemCpyOptimizer.cpp b/lib/Transforms/Scalar/MemCpyOptimizer.cpp index 389b3b740c..b13138415d 100644 --- a/lib/Transforms/Scalar/MemCpyOptimizer.cpp +++ b/lib/Transforms/Scalar/MemCpyOptimizer.cpp @@ -273,6 +273,7 @@ void MemsetRanges::addStore(int64_t Start, StoreInst *SI) { if (Start < I->Start) { I->Start = Start; I->StartPtr = SI->getPointerOperand(); + I->Alignment = SI->getAlignment(); } // Now we know that Start <= I->End and Start >= I->Start (so the startpoint diff --git a/test/Transforms/MemCpyOpt/align.ll b/test/Transforms/MemCpyOpt/align.ll new file mode 100644 index 0000000000..a9d0337852 --- /dev/null +++ b/test/Transforms/MemCpyOpt/align.ll @@ -0,0 +1,18 @@ +; RUN: opt < %s -S -memcpyopt | FileCheck %s + +; The resulting memset is only 4-byte aligned, despite containing +; a 16-byte alignmed store in the middle. + +; CHECK: call void @llvm.memset.i64(i8* %a01, i8 0, i64 16, i32 4) + +define void @foo(i32* %p) { + %a0 = getelementptr i32* %p, i64 0 + store i32 0, i32* %a0, align 4 + %a1 = getelementptr i32* %p, i64 1 + store i32 0, i32* %a1, align 16 + %a2 = getelementptr i32* %p, i64 2 + store i32 0, i32* %a2, align 4 + %a3 = getelementptr i32* %p, i64 3 + store i32 0, i32* %a3, align 4 + ret void +} |