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author | Chris Lattner <sabre@nondot.org> | 2010-09-07 20:01:38 +0000 |
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committer | Chris Lattner <sabre@nondot.org> | 2010-09-07 20:01:38 +0000 |
commit | 979ed44feb1be70e641275aaef5460320fab86a3 (patch) | |
tree | 4c8b7cb5ad9020dd64c16e19807b41574acb0012 | |
parent | dc0b06c8150071f75597a97d43529a5227031858 (diff) | |
download | external_llvm-979ed44feb1be70e641275aaef5460320fab86a3.zip external_llvm-979ed44feb1be70e641275aaef5460320fab86a3.tar.gz external_llvm-979ed44feb1be70e641275aaef5460320fab86a3.tar.bz2 |
Fix a serious performance regression introduced by r108687 on linux:
turning (fptrunc (sqrt (fpext x))) -> (sqrtf x) is great, but we have
to delete the original sqrt as well. Not doing so causes us to do
two sqrt's when building with -fmath-errno (the default on linux).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@113260 91177308-0d34-0410-b5e6-96231b3b80d8
-rw-r--r-- | lib/Transforms/InstCombine/InstCombineCasts.cpp | 7 | ||||
-rw-r--r-- | test/Transforms/InstCombine/sqrt.ll | 22 |
2 files changed, 25 insertions, 4 deletions
diff --git a/lib/Transforms/InstCombine/InstCombineCasts.cpp b/lib/Transforms/InstCombine/InstCombineCasts.cpp index 6c2477d..79a9b09 100644 --- a/lib/Transforms/InstCombine/InstCombineCasts.cpp +++ b/lib/Transforms/InstCombine/InstCombineCasts.cpp @@ -1139,7 +1139,7 @@ Instruction *InstCombiner::visitFPTrunc(FPTruncInst &CI) { Arg->getOperand(0)->getType()->isFloatTy()) { Function *Callee = Call->getCalledFunction(); Module *M = CI.getParent()->getParent()->getParent(); - Constant* SqrtfFunc = M->getOrInsertFunction("sqrtf", + Constant *SqrtfFunc = M->getOrInsertFunction("sqrtf", Callee->getAttributes(), Builder->getFloatTy(), Builder->getFloatTy(), @@ -1147,6 +1147,11 @@ Instruction *InstCombiner::visitFPTrunc(FPTruncInst &CI) { CallInst *ret = CallInst::Create(SqrtfFunc, Arg->getOperand(0), "sqrtfcall"); ret->setAttributes(Callee->getAttributes()); + + + // Remove the old Call. With -fmath-errno, it won't get marked readnone. + Call->replaceAllUsesWith(UndefValue::get(Call->getType())); + EraseInstFromFunction(*Call); return ret; } } diff --git a/test/Transforms/InstCombine/sqrt.ll b/test/Transforms/InstCombine/sqrt.ll index 6505382..69e511b 100644 --- a/test/Transforms/InstCombine/sqrt.ll +++ b/test/Transforms/InstCombine/sqrt.ll @@ -1,16 +1,32 @@ ; RUN: opt -S -instcombine %s | FileCheck %s -define float @foo(float %x) nounwind readnone ssp { +define float @test1(float %x) nounwind readnone ssp { entry: +; CHECK: @test1 ; CHECK-NOT: fpext ; CHECK-NOT: sqrt( ; CHECK: sqrtf( ; CHECK-NOT: fptrunc %conv = fpext float %x to double ; <double> [#uses=1] - %call = tail call double @sqrt(double %conv) nounwind ; <double> [#uses=1] + %call = tail call double @sqrt(double %conv) readnone nounwind ; <double> [#uses=1] %conv1 = fptrunc double %call to float ; <float> [#uses=1] ; CHECK: ret float ret float %conv1 } -declare double @sqrt(double) readnone +declare double @sqrt(double) + +; PR8096 +define float @test2(float %x) nounwind readnone ssp { +entry: +; CHECK: @test2 +; CHECK-NOT: fpext +; CHECK-NOT: sqrt( +; CHECK: sqrtf( +; CHECK-NOT: fptrunc + %conv = fpext float %x to double ; <double> [#uses=1] + %call = tail call double @sqrt(double %conv) nounwind ; <double> [#uses=1] + %conv1 = fptrunc double %call to float ; <float> [#uses=1] +; CHECK: ret float + ret float %conv1 +} |