From 2c5cc6887412597518ca4a585625b0af1ea71622 Mon Sep 17 00:00:00 2001 From: Benjamin Kramer Date: Sat, 28 May 2011 10:16:58 +0000 Subject: ConstantFoldInstOperands doesn't like compares, hand it off to instsimplify instead. Fixes PR10040. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@132254 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/Transforms/InstCombine/InstCombineSelect.cpp | 10 ++++++++++ test/Transforms/InstCombine/select.ll | 10 ++++++++++ 2 files changed, 20 insertions(+) diff --git a/lib/Transforms/InstCombine/InstCombineSelect.cpp b/lib/Transforms/InstCombine/InstCombineSelect.cpp index 2a451ce5f1..aeb3c3e880 100644 --- a/lib/Transforms/InstCombine/InstCombineSelect.cpp +++ b/lib/Transforms/InstCombine/InstCombineSelect.cpp @@ -298,6 +298,16 @@ static Value *SimplifyWithOpReplaced(Value *V, Value *Op, Value *RepOp, return SimplifyBinOp(B->getOpcode(), B->getOperand(0), RepOp, TD); } + // Same for CmpInsts. + if (CmpInst *C = dyn_cast(I)) { + if (C->getOperand(0) == Op) + return SimplifyCmpInst(C->getPredicate(), RepOp, C->getOperand(1), TD); + if (C->getOperand(1) == Op) + return SimplifyCmpInst(C->getPredicate(), C->getOperand(0), RepOp, TD); + } + + // TODO: We could hand off more cases to instsimplify here. + // If all operands are constant after substituting Op for RepOp then we can // constant fold the instruction. if (Constant *CRepOp = dyn_cast(RepOp)) { diff --git a/test/Transforms/InstCombine/select.ll b/test/Transforms/InstCombine/select.ll index 379228512c..4ca9bd2c07 100644 --- a/test/Transforms/InstCombine/select.ll +++ b/test/Transforms/InstCombine/select.ll @@ -789,3 +789,13 @@ define i32 @test59(i32 %x, i32 %y) nounwind { ; CHECK-NEXT: and i32 %x, %y ; CHECK-NEXT: ret } + +define i1 @test60(i32 %x, i1* %y) nounwind { + %cmp = icmp eq i32 %x, 0 + %load = load i1* %y, align 1 + %cmp1 = icmp slt i32 %x, 1 + %sel = select i1 %cmp, i1 %load, i1 %cmp1 + ret i1 %sel +; CHECK: @test60 +; CHECK: select +} -- cgit v1.2.3