Factor the vector load rewriting into a more generic form.

This makes it suitable for use in rewriting memcpy in the presence of
subvector memcpy intrinsics.

No functionality changed.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170324 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Chandler Carruth 2012-12-17 12:50:21 +00:00
parent 1ffe48a84b
commit 8ab1efd5fc

View File

@ -2388,31 +2388,42 @@ private:
Pass.DeadInsts.insert(I);
}
Value *rewriteVectorizedLoadInst(IRBuilder<> &IRB, LoadInst &LI, Value *OldOp) {
Value *V = IRB.CreateAlignedLoad(&NewAI, NewAI.getAlignment(),
getName(".load"));
unsigned BeginIndex = getIndex(BeginOffset);
unsigned EndIndex = getIndex(EndOffset);
assert(EndIndex > BeginIndex && "Empty vector!");
Value *extractVector(IRBuilder<> &IRB,
unsigned BeginIndex, unsigned EndIndex) {
unsigned NumElements = EndIndex - BeginIndex;
assert(NumElements <= VecTy->getNumElements() && "Too many elements!");
Value *V = IRB.CreateAlignedLoad(&NewAI, NewAI.getAlignment(),
getName(".load"));
if (NumElements == VecTy->getNumElements())
return V;
if (NumElements == 1) {
V = IRB.CreateExtractElement(V, IRB.getInt32(BeginIndex),
getName(".extract"));
DEBUG(dbgs() << " extract: " << *V << "\n");
} else if (NumElements < VecTy->getNumElements()) {
SmallVector<Constant*, 8> Mask;
Mask.reserve(NumElements);
for (unsigned i = BeginIndex; i != EndIndex; ++i)
Mask.push_back(IRB.getInt32(i));
V = IRB.CreateShuffleVector(V, UndefValue::get(V->getType()),
ConstantVector::get(Mask),
getName(".extract"));
DEBUG(dbgs() << " shuffle: " << *V << "\n");
return V;
}
SmallVector<Constant*, 8> Mask;
Mask.reserve(NumElements);
for (unsigned i = BeginIndex; i != EndIndex; ++i)
Mask.push_back(IRB.getInt32(i));
V = IRB.CreateShuffleVector(V, UndefValue::get(V->getType()),
ConstantVector::get(Mask),
getName(".extract"));
DEBUG(dbgs() << " shuffle: " << *V << "\n");
return V;
}
Value *rewriteVectorizedLoadInst(IRBuilder<> &IRB) {
unsigned BeginIndex = getIndex(BeginOffset);
unsigned EndIndex = getIndex(EndOffset);
assert(EndIndex > BeginIndex && "Empty vector!");
return extractVector(IRB, BeginIndex, EndIndex);
}
Value *rewriteIntegerLoad(IRBuilder<> &IRB, LoadInst &LI) {
assert(IntTy && "We cannot insert an integer to the alloca");
assert(!LI.isVolatile());
@ -2457,7 +2468,7 @@ private:
bool IsPtrAdjusted = false;
Value *V;
if (VecTy) {
V = rewriteVectorizedLoadInst(IRB, LI, OldOp);
V = rewriteVectorizedLoadInst(IRB);
} else if (IntTy && LI.getType()->isIntegerTy()) {
V = rewriteIntegerLoad(IRB, LI);
} else if (BeginOffset == NewAllocaBeginOffset &&