private:
void BuildRankMap(Function &F);
unsigned getRank(Value *V);
+ void canonicalizeOperands(Instruction *I);
void ReassociateExpression(BinaryOperator *I);
void RewriteExprTree(BinaryOperator *I, SmallVectorImpl<ValueEntry> &Ops);
Value *OptimizeExpression(BinaryOperator *I,
void Reassociate::BuildRankMap(Function &F) {
unsigned i = 2;
- // Assign distinct ranks to function arguments
- for (Function::arg_iterator I = F.arg_begin(), E = F.arg_end(); I != E; ++I)
+ // Assign distinct ranks to function arguments.
+ for (Function::arg_iterator I = F.arg_begin(), E = F.arg_end(); I != E; ++I) {
ValueRankMap[&*I] = ++i;
+ DEBUG(dbgs() << "Calculated Rank[" << I->getName() << "] = " << i << "\n");
+ }
ReversePostOrderTraversal<Function*> RPOT(&F);
for (ReversePostOrderTraversal<Function*>::rpo_iterator I = RPOT.begin(),
// If this is a not or neg instruction, do not count it for rank. This
// assures us that X and ~X will have the same rank.
- Type *Ty = V->getType();
- if ((!Ty->isIntegerTy() && !Ty->isFloatingPointTy()) ||
- (!BinaryOperator::isNot(I) && !BinaryOperator::isNeg(I) &&
- !BinaryOperator::isFNeg(I)))
+ if (!BinaryOperator::isNot(I) && !BinaryOperator::isNeg(I) &&
+ !BinaryOperator::isFNeg(I))
++Rank;
- //DEBUG(dbgs() << "Calculated Rank[" << V->getName() << "] = "
- // << Rank << "\n");
+ DEBUG(dbgs() << "Calculated Rank[" << V->getName() << "] = " << Rank << "\n");
return ValueRankMap[I] = Rank;
}
+// Canonicalize constants to RHS. Otherwise, sort the operands by rank.
+void Reassociate::canonicalizeOperands(Instruction *I) {
+ assert(isa<BinaryOperator>(I) && "Expected binary operator.");
+ assert(I->isCommutative() && "Expected commutative operator.");
+
+ Value *LHS = I->getOperand(0);
+ Value *RHS = I->getOperand(1);
+ unsigned LHSRank = getRank(LHS);
+ unsigned RHSRank = getRank(RHS);
+
+ if (isa<Constant>(RHS))
+ return;
+
+ if (isa<Constant>(LHS) || RHSRank < LHSRank)
+ cast<BinaryOperator>(I)->swapOperands();
+}
+
static BinaryOperator *CreateAdd(Value *S1, Value *S2, const Twine &Name,
Instruction *InsertBefore, Value *FlagsOp) {
- if (S1->getType()->isIntegerTy())
+ if (S1->getType()->isIntOrIntVectorTy())
return BinaryOperator::CreateAdd(S1, S2, Name, InsertBefore);
else {
BinaryOperator *Res =
static BinaryOperator *CreateMul(Value *S1, Value *S2, const Twine &Name,
Instruction *InsertBefore, Value *FlagsOp) {
- if (S1->getType()->isIntegerTy())
+ if (S1->getType()->isIntOrIntVectorTy())
return BinaryOperator::CreateMul(S1, S2, Name, InsertBefore);
else {
BinaryOperator *Res =
static BinaryOperator *CreateNeg(Value *S1, const Twine &Name,
Instruction *InsertBefore, Value *FlagsOp) {
- if (S1->getType()->isIntegerTy())
+ if (S1->getType()->isIntOrIntVectorTy())
return BinaryOperator::CreateNeg(S1, Name, InsertBefore);
else {
BinaryOperator *Res = BinaryOperator::CreateFNeg(S1, Name, InsertBefore);
///
static BinaryOperator *LowerNegateToMultiply(Instruction *Neg) {
Type *Ty = Neg->getType();
- Constant *NegOne = Ty->isIntegerTy() ? ConstantInt::getAllOnesValue(Ty)
- : ConstantFP::get(Ty, -1.0);
+ Constant *NegOne = Ty->isIntOrIntVectorTy() ?
+ ConstantInt::getAllOnesValue(Ty) : ConstantFP::get(Ty, -1.0);
BinaryOperator *Res = CreateMul(Neg->getOperand(1), NegOne, "", Neg, Neg);
Neg->setOperand(1, Constant::getNullValue(Ty)); // Drop use of op.
// ways to get to it.
SmallVector<std::pair<BinaryOperator*, APInt>, 8> Worklist; // (Op, Weight)
Worklist.push_back(std::make_pair(I, APInt(Bitwidth, 1)));
- bool MadeChange = false;
+ bool Changed = false;
// Leaves of the expression are values that either aren't the right kind of
// operation (eg: a constant, or a multiply in an add tree), or are, but have
// If this is a binary operation of the right kind with only one use then
// add its operands to the expression.
if (BinaryOperator *BO = isReassociableOp(Op, Opcode)) {
- assert(Visited.insert(Op) && "Not first visit!");
+ assert(Visited.insert(Op).second && "Not first visit!");
DEBUG(dbgs() << "DIRECT ADD: " << *Op << " (" << Weight << ")\n");
Worklist.push_back(std::make_pair(BO, Weight));
continue;
LeafMap::iterator It = Leaves.find(Op);
if (It == Leaves.end()) {
// Not in the leaf map. Must be the first time we saw this operand.
- assert(Visited.insert(Op) && "Not first visit!");
+ assert(Visited.insert(Op).second && "Not first visit!");
if (!Op->hasOneUse()) {
// This value has uses not accounted for by the expression, so it is
// not safe to modify. Mark it as being a leaf.
// exactly one such use, drop this new use of the leaf.
assert(!Op->hasOneUse() && "Only one use, but we got here twice!");
I->setOperand(OpIdx, UndefValue::get(I->getType()));
- MadeChange = true;
+ Changed = true;
// If the leaf is a binary operation of the right kind and we now see
// that its multiple original uses were in fact all by nodes belonging
BO = LowerNegateToMultiply(BO);
DEBUG(dbgs() << *BO << '\n');
Worklist.push_back(std::make_pair(BO, Weight));
- MadeChange = true;
+ Changed = true;
continue;
}
Ops.push_back(std::make_pair(Identity, APInt(Bitwidth, 1)));
}
- return MadeChange;
+ return Changed;
}
// RewriteExprTree - Now that the operands for this expression tree are
Constant *Undef = UndefValue::get(I->getType());
NewOp = BinaryOperator::Create(Instruction::BinaryOps(Opcode),
Undef, Undef, "", I);
- if (NewOp->getType()->isFloatingPointTy())
+ if (NewOp->getType()->isFPOrFPVectorTy())
NewOp->setFastMathFlags(I->getFastMathFlags());
} else {
NewOp = NodesToRewrite.pop_back_val();
/// version of the value is returned, and BI is left pointing at the instruction
/// that should be processed next by the reassociation pass.
static Value *NegateValue(Value *V, Instruction *BI) {
- if (ConstantFP *C = dyn_cast<ConstantFP>(V))
- return ConstantExpr::getFNeg(C);
- if (Constant *C = dyn_cast<Constant>(V))
+ if (Constant *C = dyn_cast<Constant>(V)) {
+ if (C->getType()->isFPOrFPVectorTy()) {
+ return ConstantExpr::getFNeg(C);
+ }
return ConstantExpr::getNeg(C);
+ }
+
// We are trying to expose opportunity for reassociation. One of the things
// that we want to do to achieve this is to push a negation as deep into an
++NumFound;
} while (i != Ops.size() && Ops[i].Op == TheOp);
- DEBUG(errs() << "\nFACTORING [" << NumFound << "]: " << *TheOp << '\n');
+ DEBUG(dbgs() << "\nFACTORING [" << NumFound << "]: " << *TheOp << '\n');
++NumFactor;
// Insert a new multiply.
Type *Ty = TheOp->getType();
- Constant *C = Ty->isIntegerTy() ? ConstantInt::get(Ty, NumFound)
- : ConstantFP::get(Ty, NumFound);
+ Constant *C = Ty->isIntOrIntVectorTy() ?
+ ConstantInt::get(Ty, NumFound) : ConstantFP::get(Ty, NumFound);
Instruction *Mul = CreateMul(TheOp, C, "factor", I, I);
// Now that we have inserted a multiply, optimize it. This allows us to
SmallPtrSet<Value*, 8> Duplicates;
for (unsigned i = 0, e = Factors.size(); i != e; ++i) {
Value *Factor = Factors[i];
- if (!Duplicates.insert(Factor))
+ if (!Duplicates.insert(Factor).second)
continue;
unsigned Occ = ++FactorOccurrences[Factor];
// If any factor occurred more than one time, we can pull it out.
if (MaxOcc > 1) {
- DEBUG(errs() << "\nFACTORING [" << MaxOcc << "]: " << *MaxOccVal << '\n');
+ DEBUG(dbgs() << "\nFACTORING [" << MaxOcc << "]: " << *MaxOccVal << '\n');
++NumFactor;
// Create a new instruction that uses the MaxOccVal twice. If we don't do
// from an expression will drop a use of maxocc, and this can cause
// RemoveFactorFromExpression on successive values to behave differently.
Instruction *DummyInst =
- I->getType()->isIntegerTy()
+ I->getType()->isIntOrIntVectorTy()
? BinaryOperator::CreateAdd(MaxOccVal, MaxOccVal)
: BinaryOperator::CreateFAdd(MaxOccVal, MaxOccVal);
Value *LHS = Ops.pop_back_val();
do {
- if (LHS->getType()->isIntegerTy())
+ if (LHS->getType()->isIntOrIntVectorTy())
LHS = Builder.CreateMul(LHS, Ops.pop_back_val());
else
LHS = Builder.CreateFMul(LHS, Ops.pop_back_val());
// and add that since that's where optimization actually happens.
unsigned Opcode = Op->getOpcode();
while (Op->hasOneUse() && Op->user_back()->getOpcode() == Opcode &&
- Visited.insert(Op))
+ Visited.insert(Op).second)
Op = Op->user_back();
RedoInsts.insert(Op);
}
Constant *C = C0 ? C0 : C1;
unsigned ConstIdx = C0 ? 0 : 1;
if (auto *CI = dyn_cast<ConstantInt>(C)) {
- if (!CI->isNegative())
+ if (!CI->isNegative() || CI->isMinValue(true))
return nullptr;
} else if (auto *CF = dyn_cast<ConstantFP>(C)) {
if (!CF->isNegative())
if (Instruction *Res = canonicalizeNegConstExpr(I))
I = Res;
- // Commute floating point binary operators, to canonicalize the order of their
- // operands. This can potentially expose more CSE opportunities, and makes
- // writing other transformations simpler.
- if (I->getType()->isFloatingPointTy() || I->getType()->isVectorTy()) {
-
- // FAdd and FMul can be commuted.
- unsigned Opcode = I->getOpcode();
- if (Opcode == Instruction::FMul || Opcode == Instruction::FAdd) {
- Value *LHS = I->getOperand(0);
- Value *RHS = I->getOperand(1);
- unsigned LHSRank = getRank(LHS);
- unsigned RHSRank = getRank(RHS);
-
- // Sort the operands by rank.
- if (RHSRank < LHSRank) {
- I->setOperand(0, RHS);
- I->setOperand(1, LHS);
- }
- }
+ // Commute binary operators, to canonicalize the order of their operands.
+ // This can potentially expose more CSE opportunities, and makes writing other
+ // transformations simpler.
+ if (I->isCommutative())
+ canonicalizeOperands(I);
- // FIXME: We should commute vector instructions as well. However, this
- // requires further analysis to determine the effect on later passes.
+ // TODO: We should optimize vector Xor instructions, but they are
+ // currently unsupported.
+ if (I->getType()->isVectorTy() && I->getOpcode() == Instruction::Xor)
+ return;
- // Don't try to optimize vector instructions or anything that doesn't have
- // unsafe algebra.
- if (I->getType()->isVectorTy() || !I->hasUnsafeAlgebra())
- return;
- }
+ // Don't optimize floating point instructions that don't have unsafe algebra.
+ if (I->getType()->isFloatingPointTy() && !I->hasUnsafeAlgebra())
+ return;
// Do not reassociate boolean (i1) expressions. We want to preserve the
// original order of evaluation for short-circuited comparisons that
}
void Reassociate::ReassociateExpression(BinaryOperator *I) {
- assert(!I->getType()->isVectorTy() &&
- "Reassociation of vector instructions is not supported.");
-
// First, walk the expression tree, linearizing the tree, collecting the
// operand information.
SmallVector<RepeatedValue, 8> Tree;
projects / oota-llvm.git / blobdiff