diff options
| -rw-r--r-- | lib/Transforms/InstCombine/InstCombineCompares.cpp | 9 | ||||
| -rw-r--r-- | test/Transforms/InstCombine/fcmp.ll | 11 |
2 files changed, 17 insertions, 3 deletions
diff --git a/lib/Transforms/InstCombine/InstCombineCompares.cpp b/lib/Transforms/InstCombine/InstCombineCompares.cpp index d2faab5215..26432d2eed 100644 --- a/lib/Transforms/InstCombine/InstCombineCompares.cpp +++ b/lib/Transforms/InstCombine/InstCombineCompares.cpp @@ -2837,10 +2837,13 @@ Instruction *InstCombiner::visitFCmpInst(FCmpInst &I) { APFloat F = RHSF->getValueAPF(); F.convert(*Sem, APFloat::rmNearestTiesToEven, &Lossy); - // Avoid lossy conversions and denormals. + // Avoid lossy conversions and denormals. Zero is a special case + // that's OK to convert. + F.clearSign(); if (!Lossy && - F.compare(APFloat::getSmallestNormalized(*Sem)) != - APFloat::cmpLessThan) + ((F.compare(APFloat::getSmallestNormalized(*Sem)) != + APFloat::cmpLessThan) || F.isZero())) + return new FCmpInst(I.getPredicate(), LHSExt->getOperand(0), ConstantFP::get(RHSC->getContext(), F)); break; diff --git a/test/Transforms/InstCombine/fcmp.ll b/test/Transforms/InstCombine/fcmp.ll index 2eb4f05869..d08cbf574a 100644 --- a/test/Transforms/InstCombine/fcmp.ll +++ b/test/Transforms/InstCombine/fcmp.ll @@ -58,3 +58,14 @@ define i1 @test7(float %x) nounwind readnone ssp noredzone { ; CHECK: @test7 ; CHECK-NEXT: fpext float %x to ppc_fp128 } + +define float @test8(float %x) nounwind readnone optsize ssp { + %conv = fpext float %x to double + %cmp = fcmp olt double %conv, 0.000000e+00 + %conv1 = zext i1 %cmp to i32 + %conv2 = sitofp i32 %conv1 to float + ret float %conv2 +; Float comparison to zero shouldn't cast to double. +; CHECK: @test8 +; CHECK-NEXT: fcmp olt float %x, 0.000000e+00 +} |