/// CheapToScalarize - Return true if the value is cheaper to scalarize than it
/// is to leave as a vector operation.
static bool CheapToScalarize(Value *V, bool isConstant) {
- if (isa<ConstantAggregateZero>(V))
+ if (isa<ConstantAggregateZero>(V))
return true;
if (ConstantVector *C = dyn_cast<ConstantVector>(V)) {
if (isConstant) return true;
}
Instruction *I = dyn_cast<Instruction>(V);
if (!I) return false;
-
+
// Insert element gets simplified to the inserted element or is deleted if
// this is constant idx extract element and its a constant idx insertelt.
if (I->getOpcode() == Instruction::InsertElement && isConstant &&
(CheapToScalarize(CI->getOperand(0), isConstant) ||
CheapToScalarize(CI->getOperand(1), isConstant)))
return true;
-
+
return false;
}
return std::vector<int>(NElts, 0);
if (isa<UndefValue>(SVI->getOperand(2)))
return std::vector<int>(NElts, -1);
-
+
std::vector<int> 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)
unsigned Width = PTy->getNumElements();
if (EltNo >= Width) // Out of range access.
return UndefValue::get(PTy->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 (InsertElementInst *III = dyn_cast<InsertElementInst>(V)) {
// If this is an insert to a variable element, we don't know what it is.
- if (!isa<ConstantInt>(III->getOperand(2)))
+ if (!isa<ConstantInt>(III->getOperand(2)))
return 0;
unsigned IIElt = cast<ConstantInt>(III->getOperand(2))->getZExtValue();
-
+
// If this is an insert to the element we are looking for, return the
// inserted value.
- if (EltNo == IIElt)
+ if (EltNo == IIElt)
return III->getOperand(1);
-
+
// Otherwise, the insertelement doesn't modify the value, recurse on its
// vector input.
return FindScalarElement(III->getOperand(0), EltNo);
}
-
+
if (ShuffleVectorInst *SVI = dyn_cast<ShuffleVectorInst>(V)) {
unsigned LHSWidth =
cast<VectorType>(SVI->getOperand(0)->getType())->getNumElements();
int InEl = getShuffleMask(SVI)[EltNo];
- if (InEl < 0)
+ if (InEl < 0)
return UndefValue::get(PTy->getElementType());
if (InEl < (int)LHSWidth)
return FindScalarElement(SVI->getOperand(0), InEl);
return FindScalarElement(SVI->getOperand(1), InEl - LHSWidth);
}
-
+
// Otherwise, we don't know.
return 0;
}
// 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
Constant *op0 = C->getOperand(0);
for (unsigned i = 1; i != C->getNumOperands(); ++i)
if (C->getOperand(i) != op0) {
- op0 = 0;
+ op0 = 0;
break;
}
if (op0)
return ReplaceInstUsesWith(EI, op0);
}
-
+
// If extracting a specified index from the vector, see if we can recursively
// find a previously computed scalar that was inserted into the vector.
if (ConstantInt *IdxC = dyn_cast<ConstantInt>(EI.getOperand(1))) {
unsigned IndexVal = IdxC->getZExtValue();
unsigned VectorWidth = EI.getVectorOperandType()->getNumElements();
-
+
// If this is extracting an invalid index, turn this into undef, to avoid
// crashing the code below.
if (IndexVal >= VectorWidth)
return ReplaceInstUsesWith(EI, UndefValue::get(EI.getType()));
-
+
// This instruction only demands the single element from the input vector.
// If the input vector has a single use, simplify it based on this use
// property.
return &EI;
}
}
-
+
if (Value *Elt = FindScalarElement(EI.getOperand(0), IndexVal))
return ReplaceInstUsesWith(EI, Elt);
-
+
// If the this extractelement is directly using a bitcast from a vector of
// 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 (const VectorType *VT =
+ if (const 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());
}
}
-
+
if (Instruction *I = dyn_cast<Instruction>(EI.getOperand(0))) {
// Push extractelement into predecessor operation if legal and
// profitable to do so
Value *Src;
unsigned LHSWidth =
cast<VectorType>(SVI->getOperand(0)->getType())->getNumElements();
-
+
if (SrcIdx < 0)
return ReplaceInstUsesWith(EI, UndefValue::get(EI.getType()));
if (SrcIdx < (int)LHSWidth)
}
/// CollectSingleShuffleElements - If V is a shuffle of values that ONLY returns
-/// elements from either LHS or RHS, return the shuffle mask and true.
+/// elements from either LHS or RHS, return the shuffle mask and true.
/// Otherwise, return false.
static bool CollectSingleShuffleElements(Value *V, Value *LHS, Value *RHS,
std::vector<Constant*> &Mask) {
assert(V->getType() == LHS->getType() && V->getType() == RHS->getType() &&
"Invalid CollectSingleShuffleElements");
unsigned NumElts = cast<VectorType>(V->getType())->getNumElements();
-
+
if (isa<UndefValue>(V)) {
Mask.assign(NumElts, UndefValue::get(Type::getInt32Ty(V->getContext())));
return true;
}
-
+
if (V == LHS) {
for (unsigned i = 0; i != NumElts; ++i)
Mask.push_back(ConstantInt::get(Type::getInt32Ty(V->getContext()), i));
return true;
}
-
+
if (V == RHS) {
for (unsigned i = 0; i != NumElts; ++i)
Mask.push_back(ConstantInt::get(Type::getInt32Ty(V->getContext()),
i+NumElts));
return true;
}
-
+
if (InsertElementInst *IEI = dyn_cast<InsertElementInst>(V)) {
// If this is an insert of an extract from some other vector, include it.
Value *VecOp = IEI->getOperand(0);
Value *ScalarOp = IEI->getOperand(1);
Value *IdxOp = IEI->getOperand(2);
-
+
if (!isa<ConstantInt>(IdxOp))
return false;
unsigned InsertedIdx = cast<ConstantInt>(IdxOp)->getZExtValue();
-
+
if (isa<UndefValue>(ScalarOp)) { // inserting undef into vector.
// Okay, we can handle this if the vector we are insertinting into is
// transitively ok.
// If so, update the mask to reflect the inserted undef.
Mask[InsertedIdx] = UndefValue::get(Type::getInt32Ty(V->getContext()));
return true;
- }
+ }
} else if (ExtractElementInst *EI = dyn_cast<ExtractElementInst>(ScalarOp)){
if (isa<ConstantInt>(EI->getOperand(1)) &&
EI->getOperand(0)->getType() == V->getType()) {
unsigned ExtractedIdx =
cast<ConstantInt>(EI->getOperand(1))->getZExtValue();
-
+
// This must be extracting from either LHS or RHS.
if (EI->getOperand(0) == LHS || EI->getOperand(0) == RHS) {
// Okay, we can handle this if the vector we are insertinting into is
if (CollectSingleShuffleElements(VecOp, LHS, RHS, Mask)) {
// If so, update the mask to reflect the inserted value.
if (EI->getOperand(0) == LHS) {
- Mask[InsertedIdx % NumElts] =
+ Mask[InsertedIdx % NumElts] =
ConstantInt::get(Type::getInt32Ty(V->getContext()),
ExtractedIdx);
} else {
assert(EI->getOperand(0) == RHS);
- Mask[InsertedIdx % NumElts] =
+ Mask[InsertedIdx % NumElts] =
ConstantInt::get(Type::getInt32Ty(V->getContext()),
ExtractedIdx+NumElts);
-
}
return true;
}
}
}
// TODO: Handle shufflevector here!
-
+
return false;
}
/// that computes V and the LHS value of the shuffle.
static Value *CollectShuffleElements(Value *V, std::vector<Constant*> &Mask,
Value *&RHS) {
- assert(V->getType()->isVectorTy() &&
+ assert(V->getType()->isVectorTy() &&
(RHS == 0 || V->getType() == RHS->getType()) &&
"Invalid shuffle!");
unsigned NumElts = cast<VectorType>(V->getType())->getNumElements();
-
+
if (isa<UndefValue>(V)) {
Mask.assign(NumElts, UndefValue::get(Type::getInt32Ty(V->getContext())));
return V;
Value *VecOp = IEI->getOperand(0);
Value *ScalarOp = IEI->getOperand(1);
Value *IdxOp = IEI->getOperand(2);
-
+
if (ExtractElementInst *EI = dyn_cast<ExtractElementInst>(ScalarOp)) {
if (isa<ConstantInt>(EI->getOperand(1)) && isa<ConstantInt>(IdxOp) &&
EI->getOperand(0)->getType() == V->getType()) {
unsigned ExtractedIdx =
cast<ConstantInt>(EI->getOperand(1))->getZExtValue();
unsigned InsertedIdx = cast<ConstantInt>(IdxOp)->getZExtValue();
-
+
// Either the extracted from or inserted into vector must be RHSVec,
// otherwise we'd end up with a shuffle of three inputs.
if (EI->getOperand(0) == RHS || RHS == 0) {
RHS = EI->getOperand(0);
Value *V = CollectShuffleElements(VecOp, Mask, RHS);
- Mask[InsertedIdx % NumElts] =
+ Mask[InsertedIdx % NumElts] =
ConstantInt::get(Type::getInt32Ty(V->getContext()),
NumElts+ExtractedIdx);
return V;
}
-
+
if (VecOp == RHS) {
Value *V = CollectShuffleElements(EI->getOperand(0), Mask, RHS);
// Everything but the extracted element is replaced with the RHS.
}
return V;
}
-
+
// If this insertelement is a chain that comes from exactly these two
// vectors, return the vector and the effective shuffle.
if (CollectSingleShuffleElements(IEI, EI->getOperand(0), RHS, Mask))
}
}
// TODO: Handle shufflevector here!
-
+
// Otherwise, can't do anything fancy. Return an identity vector.
for (unsigned i = 0; i != NumElts; ++i)
Mask.push_back(ConstantInt::get(Type::getInt32Ty(V->getContext()), i));
Value *VecOp = IE.getOperand(0);
Value *ScalarOp = IE.getOperand(1);
Value *IdxOp = IE.getOperand(2);
-
+
// Inserting an undef or into an undefined place, remove this.
if (isa<UndefValue>(ScalarOp) || isa<UndefValue>(IdxOp))
ReplaceInstUsesWith(IE, VecOp);
-
- // If the inserted element was extracted from some other vector, and if the
+
+ // If the inserted element was extracted from some other vector, and if the
// indexes are constant, try to turn this into a shufflevector operation.
if (ExtractElementInst *EI = dyn_cast<ExtractElementInst>(ScalarOp)) {
if (isa<ConstantInt>(EI->getOperand(1)) && isa<ConstantInt>(IdxOp) &&
unsigned ExtractedIdx =
cast<ConstantInt>(EI->getOperand(1))->getZExtValue();
unsigned InsertedIdx = cast<ConstantInt>(IdxOp)->getZExtValue();
-
+
if (ExtractedIdx >= NumVectorElts) // Out of range extract.
return ReplaceInstUsesWith(IE, VecOp);
-
+
if (InsertedIdx >= NumVectorElts) // Out of range insert.
return ReplaceInstUsesWith(IE, UndefValue::get(IE.getType()));
-
+
// If we are extracting a value from a vector, then inserting it right
// back into the same place, just use the input vector.
if (EI->getOperand(0) == VecOp && ExtractedIdx == InsertedIdx)
- return ReplaceInstUsesWith(IE, VecOp);
-
+ return ReplaceInstUsesWith(IE, VecOp);
+
// If this insertelement isn't used by some other insertelement, turn it
// (and any insertelements it points to), into one big shuffle.
if (!IE.hasOneUse() || !isa<InsertElementInst>(IE.use_back())) {
}
}
}
-
+
unsigned VWidth = cast<VectorType>(VecOp->getType())->getNumElements();
APInt UndefElts(VWidth, 0);
APInt AllOnesEltMask(APInt::getAllOnesValue(VWidth));
if (SimplifyDemandedVectorElts(&IE, AllOnesEltMask, UndefElts))
return &IE;
-
+
return 0;
}
Value *LHS = SVI.getOperand(0);
Value *RHS = SVI.getOperand(1);
std::vector<int> Mask = getShuffleMask(&SVI);
-
+
bool MadeChange = false;
-
+
// Undefined shuffle mask -> undefined value.
if (isa<UndefValue>(SVI.getOperand(2)))
return ReplaceInstUsesWith(SVI, UndefValue::get(SVI.getType()));
-
+
unsigned VWidth = cast<VectorType>(SVI.getType())->getNumElements();
-
+
if (VWidth != cast<VectorType>(LHS->getType())->getNumElements())
return 0;
-
+
APInt UndefElts(VWidth, 0);
APInt AllOnesEltMask(APInt::getAllOnesValue(VWidth));
if (SimplifyDemandedVectorElts(&SVI, AllOnesEltMask, UndefElts)) {
RHS = SVI.getOperand(1);
MadeChange = true;
}
-
+
// Canonicalize shuffle(x ,x,mask) -> shuffle(x, undef,mask')
// Canonicalize shuffle(undef,x,mask) -> shuffle(x, undef,mask').
if (LHS == RHS || isa<UndefValue>(LHS)) {
// shuffle(undef,undef,mask) -> undef.
return ReplaceInstUsesWith(SVI, LHS);
}
-
+
// Remap any references to RHS to use LHS.
std::vector<Constant*> Elts;
for (unsigned i = 0, e = Mask.size(); i != e; ++i) {
RHS = SVI.getOperand(1);
MadeChange = true;
}
-
+
// Analyze the shuffle, are the LHS or RHS and identity shuffles?
bool isLHSID = true, isRHSID = true;
-
+
for (unsigned i = 0, e = Mask.size(); i != e; ++i) {
if (Mask[i] < 0) continue; // Ignore undef values.
// Is this an identity shuffle of the LHS value?
isLHSID &= (Mask[i] == (int)i);
-
+
// Is this an identity shuffle of the RHS value?
isRHSID &= (Mask[i]-e == i);
}
-
+
// Eliminate identity shuffles.
if (isLHSID) return ReplaceInstUsesWith(SVI, LHS);
if (isRHSID) return ReplaceInstUsesWith(SVI, RHS);
-
+
// If the LHS is a shufflevector itself, see if we can combine it with this
// one without producing an unusual shuffle. Here we are really conservative:
// we are absolutely afraid of producing a shuffle mask not in the input
if (ShuffleVectorInst *LHSSVI = dyn_cast<ShuffleVectorInst>(LHS)) {
if (isa<UndefValue>(RHS)) {
std::vector<int> LHSMask = getShuffleMask(LHSSVI);
-
+
if (LHSMask.size() == Mask.size()) {
std::vector<int> NewMask;
bool isSplat = true;
}
NewMask.push_back(MaskElt);
}
-
+
// If the result mask is equal to the src shuffle or this
// shuffle mask, do the replacement.
if (isSplat || NewMask == LHSMask || NewMask == Mask) {
}
}
}
-
+
return MadeChange ? &SVI : 0;
}