From 92346c315e001080f359f8d2ea10610941e98c6d Mon Sep 17 00:00:00 2001 From: Chris Lattner Date: Fri, 31 Mar 2006 18:25:14 +0000 Subject: extractelement(undef,x) -> undef llvm-svn: 27300 --- llvm/lib/Transforms/Scalar/InstructionCombining.cpp | 14 ++++++++------ 1 file changed, 8 insertions(+), 6 deletions(-) (limited to 'llvm/lib/Transforms') diff --git a/llvm/lib/Transforms/Scalar/InstructionCombining.cpp b/llvm/lib/Transforms/Scalar/InstructionCombining.cpp index cd734568ba5..f69d869c12e 100644 --- a/llvm/lib/Transforms/Scalar/InstructionCombining.cpp +++ b/llvm/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 -- cgit v1.2.3