eliminate the Constant::getVectorElements method. There are better (and

more robust) ways to do what it was doing now.  Also, add static methods
for decoding a ShuffleVector mask.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@149028 91177308-0d34-0410-b5e6-96231b3b80d8

3 files changed, 18 insertions, 48 deletions

diff --git a/lib/VMCore/ConstantFold.cpp b/lib/VMCore/ConstantFold.cpp
index 9a3a991..abc019f 100644
--- a/lib/VMCore/ConstantFold.cpp
+++ b/lib/VMCore/ConstantFold.cpp
@@ -1697,20 +1697,20 @@ Constant *llvm::ConstantFoldCompareInstruction(unsigned short pred,
                                         R==APFloat::cmpEqual);
     }
   } else if (C1->getType()->isVectorTy()) {
-    SmallVector<Constant*, 16> C1Elts, C2Elts;
-    C1->getVectorElements(C1Elts);
-    C2->getVectorElements(C2Elts);
-    if (C1Elts.empty() || C2Elts.empty())
-      return 0;
-
     // If we can constant fold the comparison of each element, constant fold
     // the whole vector comparison.
     SmallVector<Constant*, 4> ResElts;
     // Compare the elements, producing an i1 result or constant expr.
-    for (unsigned i = 0, e = C1Elts.size(); i != e; ++i)
-      ResElts.push_back(ConstantExpr::getCompare(pred, C1Elts[i], C2Elts[i]));
-
-    return ConstantVector::get(ResElts);
+    for (unsigned i = 0, e = C1->getType()->getVectorNumElements(); i != e;++i){
+      Constant *C1E = C1->getAggregateElement(i);
+      Constant *C2E = C2->getAggregateElement(i);
+      if (C1E == 0 || C2E == 0) break;
+      
+      ResElts.push_back(ConstantExpr::getCompare(pred, C1E, C2E));
+    }
+    
+    if (ResElts.size() == C1->getType()->getVectorNumElements())
+      return ConstantVector::get(ResElts);
   }
 
   if (C1->getType()->isFloatingPointTy()) {
diff --git a/lib/VMCore/Constants.cpp b/lib/VMCore/Constants.cpp
index f5239e1..2530b63 100644
--- a/lib/VMCore/Constants.cpp
+++ b/lib/VMCore/Constants.cpp
@@ -312,36 +312,6 @@ Constant::PossibleRelocationsTy Constant::getRelocationInfo() const {
   return Result;
 }
 
-
-/// getVectorElements - This method, which is only valid on constant of vector
-/// type, returns the elements of the vector in the specified smallvector.
-/// This handles breaking down a vector undef into undef elements, etc.  For
-/// constant exprs and other cases we can't handle, we return an empty vector.
-void Constant::getVectorElements(SmallVectorImpl<Constant*> &Elts) const {
-  assert(getType()->isVectorTy() && "Not a vector constant!");
-  
-  if (const ConstantVector *CV = dyn_cast<ConstantVector>(this)) {
-    for (unsigned i = 0, e = CV->getNumOperands(); i != e; ++i)
-      Elts.push_back(CV->getOperand(i));
-    return;
-  }
-  
-  VectorType *VT = cast<VectorType>(getType());
-  if (isa<ConstantAggregateZero>(this)) {
-    Elts.assign(VT->getNumElements(), 
-                Constant::getNullValue(VT->getElementType()));
-    return;
-  }
-  
-  if (isa<UndefValue>(this)) {
-    Elts.assign(VT->getNumElements(), UndefValue::get(VT->getElementType()));
-    return;
-  }
-  
-  // Unknown type, must be constant expr etc.
-}
-
-
 /// removeDeadUsersOfConstant - If the specified constantexpr is dead, remove
 /// it.  This involves recursively eliminating any dead users of the
 /// constantexpr.
diff --git a/lib/VMCore/Instructions.cpp b/lib/VMCore/Instructions.cpp
index 1de7c01..a0fb91a 100644
--- a/lib/VMCore/Instructions.cpp
+++ b/lib/VMCore/Instructions.cpp
@@ -1625,11 +1625,11 @@ bool ShuffleVectorInst::isValidOperands(const Value *V1, const Value *V2,
 /// getMaskValue - Return the index from the shuffle mask for the specified
 /// output result.  This is either -1 if the element is undef or a number less
 /// than 2*numelements.
-int ShuffleVectorInst::getMaskValue(unsigned i) const {
-  assert(i < getType()->getNumElements() && "Index out of range");
-  if (ConstantDataSequential *CDS =dyn_cast<ConstantDataSequential>(getMask()))
+int ShuffleVectorInst::getMaskValue(Constant *Mask, unsigned i) {
+  assert(i < Mask->getType()->getVectorNumElements() && "Index out of range");
+  if (ConstantDataSequential *CDS =dyn_cast<ConstantDataSequential>(Mask))
     return CDS->getElementAsInteger(i);
-  Constant *C = getMask()->getAggregateElement(i);
+  Constant *C = Mask->getAggregateElement(i);
   if (isa<UndefValue>(C))
     return -1;
   return cast<ConstantInt>(C)->getZExtValue();
@@ -1637,15 +1637,15 @@ int ShuffleVectorInst::getMaskValue(unsigned i) const {
 
 /// getShuffleMask - Return the full mask for this instruction, where each
 /// element is the element number and undef's are returned as -1.
-void ShuffleVectorInst::getShuffleMask(SmallVectorImpl<int> &Result) const {
-  unsigned NumElts = getType()->getNumElements();
+void ShuffleVectorInst::getShuffleMask(Constant *Mask,
+                                       SmallVectorImpl<int> &Result) {
+  unsigned NumElts = Mask->getType()->getVectorNumElements();
   
-  if (ConstantDataSequential *CDS=dyn_cast<ConstantDataSequential>(getMask())) {
+  if (ConstantDataSequential *CDS=dyn_cast<ConstantDataSequential>(Mask)) {
     for (unsigned i = 0; i != NumElts; ++i)
       Result.push_back(CDS->getElementAsInteger(i));
     return;
   }    
-  Constant *Mask = getMask();
   for (unsigned i = 0; i != NumElts; ++i) {
     Constant *C = Mask->getAggregateElement(i);
     Result.push_back(isa<UndefValue>(C) ? -1 :