some general cleanup, using new methods and tidying up old code.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@149006 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 26 insertions, 69 deletions

diff --git a/lib/Transforms/InstCombine/InstCombineVectorOps.cpp b/lib/Transforms/InstCombine/InstCombineVectorOps.cpp
index 0f8ffb9..050cb48 100644
--- a/lib/Transforms/InstCombine/InstCombineVectorOps.cpp
+++ b/lib/Transforms/InstCombine/InstCombineVectorOps.cpp
@@ -19,14 +19,13 @@ using namespace llvm;
 /// is to leave as a vector operation.  isConstant indicates whether we're
 /// extracting one known element.  If false we're extracting a variable index.
 static bool CheapToScalarize(Value *V, bool isConstant) {
-  if (isa<ConstantAggregateZero>(V))
-    return true;
-  if (ConstantVector *C = dyn_cast<ConstantVector>(V)) {
+  if (Constant *C = dyn_cast<Constant>(V)) {
     if (isConstant) return true;
-    // If all elts are the same, we can extract.
-    Constant *Op0 = C->getOperand(0);
-    for (unsigned i = 1; i < C->getNumOperands(); ++i)
-      if (C->getOperand(i) != Op0)
+
+    // If all elts are the same, we can extract it and use any of the values.
+    Constant *Op0 = C->getAggregateElement(0U);
+    for (unsigned i = 1, e = V->getType()->getVectorNumElements(); i != e; ++i)
+      if (C->getAggregateElement(i) != Op0)
         return false;
     return true;
   }
@@ -54,41 +53,18 @@ static bool CheapToScalarize(Value *V, bool isConstant) {
   return false;
 }
 
-/// getShuffleMask - Read and decode a shufflevector mask.
-/// Turn undef elements into negative values.
-static SmallVector<int, 16> getShuffleMask(const ShuffleVectorInst *SVI) {
-  unsigned NElts = SVI->getType()->getNumElements();
-  if (isa<ConstantAggregateZero>(SVI->getOperand(2)))
-    return SmallVector<int, 16>(NElts, 0);
-  if (isa<UndefValue>(SVI->getOperand(2)))
-    return SmallVector<int, 16>(NElts, -1);
-
-  SmallVector<int, 16> Result;
-  const ConstantVector *CP = cast<ConstantVector>(SVI->getOperand(2));
-  for (User::const_op_iterator i = CP->op_begin(), e = CP->op_end(); i!=e; ++i)
-    if (isa<UndefValue>(*i))
-      Result.push_back(-1);  // undef
-    else
-      Result.push_back(cast<ConstantInt>(*i)->getZExtValue());
-  return Result;
-}
-
 /// FindScalarElement - Given a vector and an element number, see if the scalar
 /// value is already around as a register, for example if it were inserted then
 /// extracted from the vector.
 static Value *FindScalarElement(Value *V, unsigned EltNo) {
   assert(V->getType()->isVectorTy() && "Not looking at a vector?");
-  VectorType *PTy = cast<VectorType>(V->getType());
-  unsigned Width = PTy->getNumElements();
+  VectorType *VTy = cast<VectorType>(V->getType());
+  unsigned Width = VTy->getNumElements();
   if (EltNo >= Width)  // Out of range access.
-    return UndefValue::get(PTy->getElementType());
+    return UndefValue::get(VTy->getElementType());
 
-  if (isa<UndefValue>(V))
-    return UndefValue::get(PTy->getElementType());
-  if (isa<ConstantAggregateZero>(V))
-    return Constant::getNullValue(PTy->getElementType());
-  if (ConstantVector *CP = dyn_cast<ConstantVector>(V))
-    return CP->getOperand(EltNo);
+  if (Constant *C = dyn_cast<Constant>(V))
+    return C->getAggregateElement(EltNo);
 
   if (InsertElementInst *III = dyn_cast<InsertElementInst>(V)) {
     // If this is an insert to a variable element, we don't know what it is.
@@ -107,11 +83,10 @@ static Value *FindScalarElement(Value *V, unsigned EltNo) {
   }
 
   if (ShuffleVectorInst *SVI = dyn_cast<ShuffleVectorInst>(V)) {
-    unsigned LHSWidth =
-      cast<VectorType>(SVI->getOperand(0)->getType())->getNumElements();
+    unsigned LHSWidth = SVI->getOperand(0)->getType()->getVectorNumElements();
     int InEl = SVI->getMaskValue(EltNo);
     if (InEl < 0)
-      return UndefValue::get(PTy->getElementType());
+      return UndefValue::get(VTy->getElementType());
     if (InEl < (int)LHSWidth)
       return FindScalarElement(SVI->getOperand(0), InEl);
     return FindScalarElement(SVI->getOperand(1), InEl - LHSWidth);
@@ -122,27 +97,11 @@ static Value *FindScalarElement(Value *V, unsigned EltNo) {
 }
 
 Instruction *InstCombiner::visitExtractElementInst(ExtractElementInst &EI) {
-  // If vector val is undef, replace extract with scalar undef.
-  if (isa<UndefValue>(EI.getOperand(0)))
-    return ReplaceInstUsesWith(EI, UndefValue::get(EI.getType()));
-
-  // If vector val is constant 0, replace extract with scalar 0.
-  if (isa<ConstantAggregateZero>(EI.getOperand(0)))
-    return ReplaceInstUsesWith(EI, Constant::getNullValue(EI.getType()));
-
-  if (ConstantVector *C = dyn_cast<ConstantVector>(EI.getOperand(0))) {
-    // If vector val is constant with all elements the same, replace EI with
-    // that element. When the elements are not identical, we cannot replace yet
-    // (we do that below, but only when the index is constant).
-    Constant *op0 = C->getOperand(0);
-    for (unsigned i = 1; i != C->getNumOperands(); ++i)
-      if (C->getOperand(i) != op0) {
-        op0 = 0;
-        break;
-      }
-    if (op0)
-      return ReplaceInstUsesWith(EI, op0);
-  }
+  // If vector val is constant with all elements the same, replace EI with
+  // that element.  We handle a known element # below.
+  if (Constant *C = dyn_cast<Constant>(EI.getOperand(0)))
+    if (CheapToScalarize(C, false))
+      return ReplaceInstUsesWith(EI, C->getAggregateElement(0U));
 
   // If extracting a specified index from the vector, see if we can recursively
   // find a previously computed scalar that was inserted into the vector.
@@ -176,8 +135,7 @@ Instruction *InstCombiner::visitExtractElementInst(ExtractElementInst &EI) {
     // the same number of elements, see if we can find the source element from
     // it.  In this case, we will end up needing to bitcast the scalars.
     if (BitCastInst *BCI = dyn_cast<BitCastInst>(EI.getOperand(0))) {
-      if (VectorType *VT =
-          dyn_cast<VectorType>(BCI->getOperand(0)->getType()))
+      if (VectorType *VT = dyn_cast<VectorType>(BCI->getOperand(0)->getType()))
         if (VT->getNumElements() == VectorWidth)
           if (Value *Elt = FindScalarElement(BCI->getOperand(0), IndexVal))
             return new BitCastInst(Elt, EI.getType());
@@ -216,7 +174,7 @@ Instruction *InstCombiner::visitExtractElementInst(ExtractElementInst &EI) {
         int SrcIdx = SVI->getMaskValue(Elt->getZExtValue());
         Value *Src;
         unsigned LHSWidth =
-          cast<VectorType>(SVI->getOperand(0)->getType())->getNumElements();
+          SVI->getOperand(0)->getType()->getVectorNumElements();
 
         if (SrcIdx < 0)
           return ReplaceInstUsesWith(EI, UndefValue::get(EI.getType()));
@@ -452,7 +410,7 @@ Instruction *InstCombiner::visitInsertElementInst(InsertElementInst &IE) {
 Instruction *InstCombiner::visitShuffleVectorInst(ShuffleVectorInst &SVI) {
   Value *LHS = SVI.getOperand(0);
   Value *RHS = SVI.getOperand(1);
-  SmallVector<int, 16> Mask = getShuffleMask(&SVI);
+  SmallVector<int, 16> Mask = SVI.getShuffleMask();
 
   bool MadeChange = false;
 
@@ -623,12 +581,11 @@ Instruction *InstCombiner::visitShuffleVectorInst(ShuffleVectorInst &SVI) {
 
   SmallVector<int, 16> LHSMask;
   SmallVector<int, 16> RHSMask;
-  if (newLHS != LHS) {
-    LHSMask = getShuffleMask(LHSShuffle);
-  }
-  if (RHSShuffle && newRHS != RHS) {
-    RHSMask = getShuffleMask(RHSShuffle);
-  }
+  if (newLHS != LHS)
+    LHSMask = LHSShuffle->getShuffleMask();
+  if (RHSShuffle && newRHS != RHS)
+    RHSMask = RHSShuffle->getShuffleMask();
+
   unsigned newLHSWidth = (newLHS != LHS) ? LHSOp0Width : LHSWidth;
   SmallVector<int, 16> newMask;
   bool isSplat = true;