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| author | Arnold Schwaighofer <aschwaighofer@apple.com> | 2014-06-26 19:51:19 +0000 |
|---|---|---|
| committer | Arnold Schwaighofer <aschwaighofer@apple.com> | 2014-06-26 19:51:19 +0000 |
| commit | c2d93c404820178d55f440d4aa46e75d4b5c7b64 (patch) | |
| tree | 9b7fc72267dce99c537c439ee88b0a7fc0f52774 | |
| parent | db1c4942760e926a6c606b924d47ec18d513b674 (diff) | |
| download | llvm-c2d93c404820178d55f440d4aa46e75d4b5c7b64.tar.gz llvm-c2d93c404820178d55f440d4aa46e75d4b5c7b64.tar.bz2 llvm-c2d93c404820178d55f440d4aa46e75d4b5c7b64.tar.xz | |
GVN: Preserve invariant.load metadata
If both instructions to be replaced are marked invariant the resulting
instruction is invariant.
rdar://13358910
Fix by Erik Eckstein!
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211801 91177308-0d34-0410-b5e6-96231b3b80d8
| -rw-r--r-- | lib/Transforms/Scalar/GVN.cpp | 4 | ||||
| -rw-r--r-- | test/Transforms/GVN/invariant-load.ll | 30 |
2 files changed, 34 insertions, 0 deletions
diff --git a/lib/Transforms/Scalar/GVN.cpp b/lib/Transforms/Scalar/GVN.cpp index 56781d44aa..106eba099c 100644 --- a/lib/Transforms/Scalar/GVN.cpp +++ b/lib/Transforms/Scalar/GVN.cpp @@ -1798,6 +1798,10 @@ static void patchReplacementInstruction(Instruction *I, Value *Repl) { case LLVMContext::MD_fpmath: ReplInst->setMetadata(Kind, MDNode::getMostGenericFPMath(IMD, ReplMD)); break; + case LLVMContext::MD_invariant_load: + // Only set the !invariant.load if it is present in both instructions. + ReplInst->setMetadata(Kind, IMD); + break; } } } diff --git a/test/Transforms/GVN/invariant-load.ll b/test/Transforms/GVN/invariant-load.ll new file mode 100644 index 0000000000..73a12787fb --- /dev/null +++ b/test/Transforms/GVN/invariant-load.ll @@ -0,0 +1,30 @@ +; RUN: opt -basicaa -gvn -S < %s | FileCheck %s + +define i32 @test1(i32* nocapture %p, i8* nocapture %q) { +; CHECK-LABEL: test1 +; CHECK: %x = load i32* %p, align 4, !invariant.load !0 +; CHECK-NOT: %y = load +entry: + %x = load i32* %p, align 4, !invariant.load !0 + %conv = trunc i32 %x to i8 + store i8 %conv, i8* %q, align 1 + %y = load i32* %p, align 4, !invariant.load !0 + %add = add i32 %y, 1 + ret i32 %add +} + +define i32 @test2(i32* nocapture %p, i8* nocapture %q) { +; CHECK-LABEL: test2 +; CHECK-NOT: !invariant.load +; CHECK-NOT: %y = load +entry: + %x = load i32* %p, align 4 + %conv = trunc i32 %x to i8 + store i8 %conv, i8* %q, align 1 + %y = load i32* %p, align 4, !invariant.load !0 + %add = add i32 %y, 1 + ret i32 %add +} + +!0 = metadata !{ } + |