/// to a given vectorization factor (VF).
class SingleBlockLoopVectorizer {
public:
-
/// Ctor.
SingleBlockLoopVectorizer(Loop *OrigLoop, ScalarEvolution *Se, LoopInfo *Li,
LPPassManager *Lpm, unsigned VecWidth):
/// broadcast them into a vector.
Value *getVectorValue(Value *V);
+ typedef DenseMap<Value*, Value*> ValueMap;
+
/// The original loop.
Loop *Orig;
// Scev analysis to use.
/// The induction variable of the old basic block.
PHINode *OldInduction;
// Maps scalars to widened vectors.
- DenseMap<Value*, Value*> WidenMap;
+ ValueMap WidenMap;
};
/// Perform the vectorization legality check. This class does not look at the
if (!SE->isLoopInvariant(SE->getSCEV(Gep->getOperand(i)), Orig))
return false;
- // The last operand has to be the induction in order to emit
- // a wide load/store.
+ // We can emit wide load/stores only of the last index is the induction
+ // variable.
const SCEV *Last = SE->getSCEV(LastIndex);
if (const SCEVAddRecExpr *AR = dyn_cast<SCEVAddRecExpr>(Last)) {
const SCEV *Step = AR->getStepRecurrence(*SE);
}
Value *SingleBlockLoopVectorizer::getVectorValue(Value *V) {
- if (WidenMap.count(V))
- return WidenMap[V];
- return getBroadcastInstrs(V);
+ // If we saved a vectorized copy of V, use it.
+ ValueMap::iterator it = WidenMap.find(V);
+ if (it != WidenMap.end())
+ return it->second;
+
+ // Broadcast V and save the value for future uses.
+ Value *B = getBroadcastInstrs(V);
+ WidenMap[V] = B;
+ return B;
}
void SingleBlockLoopVectorizer::scalarizeInstruction(Instruction *Instr) {