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A splat of a vector constant of all zero or all one is the vector constant. 

llvm-svn: 29234
This commit is contained in:
Evan Cheng 2006-07-20 23:09:47 +00:00
parent f98bc5288e
commit 4cf0238720
1 changed files with 2 additions and 0 deletions
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2
llvm/lib/Target/X86/X86ISelLowering.cpp
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@ -2393,6 +2393,8 @@ X86TargetLowering::LowerVECTOR_SHUFFLE(SDOperand Op, SelectionDAG &DAG) {
bool V2IsUndef = V2.getOpcode() == ISD::UNDEF;
if (isSplatMask(PermMask.Val)) {
if (ISD::isBuildVectorAllZeros(V1.Val) || ISD::isBuildVectorAllOnes(V1.Val))
return V1;
if (NumElems <= 4) return Op;
// Promote it to a v4i32 splat.
return PromoteSplat(Op, DAG);