[SelectionDAGBuilder] Hide existence of ConstantDataVector vector from visitGetElementPtr.

ConstantDataVector is a specialized verison of ConstantVector
that stores data in a packed array of bits instead of as
individual pointers to other Constants. But we really shouldn't
expose that if we can void it. And we should handle regular
ConstantVector equally well.

This removes a dyn_cast to ConstantDataVector and just calls
getSplatValue directly on a Constant* if the type is a vector.

llvm-svn: 370018

1 files changed, 5 insertions, 6 deletions

diff --git a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
index fde3d97ac8e..cf438691308 100644
--- a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
@@ -3826,7 +3826,7 @@ void SelectionDAGBuilder::visitGetElementPtr(const User &I) {
   // Normalize Vector GEP - all scalar operands should be converted to the
   // splat vector.
   unsigned VectorWidth = I.getType()->isVectorTy() ?
-    cast<VectorType>(I.getType())->getVectorNumElements() : 0;
+    I.getType()->getVectorNumElements() : 0;
 
   if (VectorWidth && !N.getValueType().isVector()) {
     LLVMContext &Context = *DAG.getContext();
@@ -3859,12 +3859,11 @@ void SelectionDAGBuilder::visitGetElementPtr(const User &I) {
 
       // If this is a scalar constant or a splat vector of constants,
       // handle it quickly.
-      const auto *CI = dyn_cast<ConstantInt>(Idx);
-      if (!CI && isa<ConstantDataVector>(Idx) &&
-          cast<ConstantDataVector>(Idx)->getSplatValue())
-        CI = cast<ConstantInt>(cast<ConstantDataVector>(Idx)->getSplatValue());
+      const auto *C = dyn_cast<Constant>(Idx);
+      if (C && isa<VectorType>(C->getType()))
+        C = C->getSplatValue();
 
-      if (CI) {
+      if (const auto *CI = dyn_cast_or_null<ConstantInt>(C)) {
         if (CI->isZero())
           continue;
         APInt Offs = ElementSize * CI->getValue().sextOrTrunc(IdxSize);