Remove some dead code from the days llvm had type planes.

[oota-llvm.git] / lib / VMCore / ConstantFold.cpp

diff --git a/lib/VMCore/ConstantFold.cpp b/lib/VMCore/ConstantFold.cpp
index 93ee7fe59aeaa44c9330f3d4549d75f4a7276064..9fa41b373cd7ee65a3c4873d39fe59255c064bc9 100644 (file)
--- a/lib/VMCore/ConstantFold.cpp
+++ b/lib/VMCore/ConstantFold.cpp
@@ -126,6 +126,7 @@ static Constant *FoldBitCast(Constant *V, const Type *DestTy) {
     if (const VectorType *SrcTy = dyn_cast<VectorType>(V->getType())) {
       assert(DestPTy->getBitWidth() == SrcTy->getBitWidth() &&
              "Not cast between same sized vectors!");
+      SrcTy = NULL;
       // First, check for null.  Undef is already handled.
       if (isa<ConstantAggregateZero>(V))
         return Constant::getNullValue(DestTy);
@@ -133,6 +134,12 @@ static Constant *FoldBitCast(Constant *V, const Type *DestTy) {
       if (ConstantVector *CV = dyn_cast<ConstantVector>(V))
         return BitCastConstantVector(CV, DestPTy);
     }
+
+    // Canonicalize scalar-to-vector bitcasts into vector-to-vector bitcasts
+    // This allows for other simplifications (although some of them
+    // can only be handled by Analysis/ConstantFolding.cpp).
+    if (isa<ConstantInt>(V) || isa<ConstantFP>(V))
+      return ConstantExpr::getBitCast(ConstantVector::get(&V, 1), DestPTy);
   }
   
   // Finally, implement bitcast folding now.   The code below doesn't handle
@@ -417,24 +424,25 @@ Constant *llvm::ConstantFoldShuffleVectorInstruction(const Constant *V1,
                                                      const Constant *Mask) {
   // Undefined shuffle mask -> undefined value.
   if (isa<UndefValue>(Mask)) return UndefValue::get(V1->getType());
-  
-  unsigned NumElts = cast<VectorType>(V1->getType())->getNumElements();
+
+  unsigned MaskNumElts = cast<VectorType>(Mask->getType())->getNumElements();
+  unsigned SrcNumElts = cast<VectorType>(V1->getType())->getNumElements();
   const Type *EltTy = cast<VectorType>(V1->getType())->getElementType();
-  
+
   // Loop over the shuffle mask, evaluating each element.
   SmallVector<Constant*, 32> Result;
-  for (unsigned i = 0; i != NumElts; ++i) {
+  for (unsigned i = 0; i != MaskNumElts; ++i) {
     Constant *InElt = GetVectorElement(Mask, i);
     if (InElt == 0) return 0;
-    
+
     if (isa<UndefValue>(InElt))
       InElt = UndefValue::get(EltTy);
     else if (ConstantInt *CI = dyn_cast<ConstantInt>(InElt)) {
       unsigned Elt = CI->getZExtValue();
-      if (Elt >= NumElts*2)
+      if (Elt >= SrcNumElts*2)
         InElt = UndefValue::get(EltTy);
-      else if (Elt >= NumElts)
-        InElt = GetVectorElement(V2, Elt-NumElts);
+      else if (Elt >= SrcNumElts)
+        InElt = GetVectorElement(V2, Elt - SrcNumElts);
       else
         InElt = GetVectorElement(V1, Elt);
       if (InElt == 0) return 0;
@@ -444,7 +452,7 @@ Constant *llvm::ConstantFoldShuffleVectorInstruction(const Constant *V1,
     }
     Result.push_back(InElt);
   }
-  
+
   return ConstantVector::get(&Result[0], Result.size());
 }