[X86] Use DAG.getConstant instead of getZeroVector in combinePMULDQ.

getZeroVector canonicalizes the type to vXi32, but that's a
legalization action. We should use the most correct type if
possible.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@371345 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Target/X86/X86ISelLowering.cpp b/lib/Target/X86/X86ISelLowering.cpp
index c7844220dfcb037785f249423f3e2b99151e7307..3950b292ab3a3ae032bb1296bd9673cf1170b0e3 100644 (file)
--- a/lib/Target/X86/X86ISelLowering.cpp
+++ b/lib/Target/X86/X86ISelLowering.cpp
@@ -44768,7 +44768,7 @@ static SDValue combinePMULDQ(SDNode *N, SelectionDAG &DAG,
   // Multiply by zero.
   // Don't return RHS as it may contain UNDEFs.
   if (ISD::isBuildVectorAllZeros(RHS.getNode()))
-    return getZeroVector(N->getSimpleValueType(0), Subtarget, DAG, SDLoc(N));
+    return DAG.getConstant(0, SDLoc(N), N->getValueType(0));
 
   // PMULDQ/PMULUDQ only uses lower 32 bits from each vector element.
   const TargetLowering &TLI = DAG.getTargetLoweringInfo();