From 1f13c88939e2d243c9802f7da83ae8daccb285eb Mon Sep 17 00:00:00 2001 From: Chris Lattner Date: Fri, 31 Mar 2006 18:25:14 +0000 Subject: [PATCH] extractelement(undef,x) -> undef git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@27300 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/Transforms/Scalar/InstructionCombining.cpp | 14 ++++++++------ 1 file changed, 8 insertions(+), 6 deletions(-) diff --git a/lib/Transforms/Scalar/InstructionCombining.cpp b/lib/Transforms/Scalar/InstructionCombining.cpp index cd734568ba5..f69d869c12e 100644 --- a/lib/Transforms/Scalar/InstructionCombining.cpp +++ b/lib/Transforms/Scalar/InstructionCombining.cpp @@ -6655,12 +6655,14 @@ static bool CheapToScalarize(Value *V, bool isConstant) { } Instruction *InstCombiner::visitExtractElementInst(ExtractElementInst &EI) { - if (ConstantAggregateZero *C = - dyn_cast(EI.getOperand(0))) { - // If packed val is constant 0, replace extract with scalar 0 - const Type *Ty = cast(C->getType())->getElementType(); - return ReplaceInstUsesWith(EI, Constant::getNullValue(Ty)); - } + // If packed val is undef, replace extract with scalar undef. + if (isa(EI.getOperand(0))) + return ReplaceInstUsesWith(EI, UndefValue::get(EI.getType())); + + // If packed val is constant 0, replace extract with scalar 0. + if (isa(EI.getOperand(0))) + return ReplaceInstUsesWith(EI, Constant::getNullValue(EI.getType())); + if (ConstantPacked *C = dyn_cast(EI.getOperand(0))) { // If packed val is constant with uniform operands, replace EI // with that operand -- 2.34.1