PR4340: Run SimplifyDemandedVectorElts on insertelement instructions;

sometimes it can find simplifications that won't be found otherwise.

llvm-svn: 73006

1 files changed, 6 insertions, 0 deletions

diff --git a/llvm/lib/Transforms/Scalar/InstructionCombining.cpp b/llvm/lib/Transforms/Scalar/InstructionCombining.cpp
index 97bd34c771c..6d2ff0e3e53 100644
--- a/llvm/lib/Transforms/Scalar/InstructionCombining.cpp
+++ b/llvm/lib/Transforms/Scalar/InstructionCombining.cpp
@@ -12579,6 +12579,12 @@ Instruction *InstCombiner::visitInsertElementInst(InsertElementInst &IE) {
     }
   }
 
+  unsigned VWidth = cast<VectorType>(VecOp->getType())->getNumElements();
+  APInt UndefElts(VWidth, 0);
+  APInt AllOnesEltMask(APInt::getAllOnesValue(VWidth));
+  if (SimplifyDemandedVectorElts(&IE, AllOnesEltMask, UndefElts))
+    return &IE;
+
   return 0;
 }