Whitespace cleanup.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@156034 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Bill Wendling 2012-05-02 23:43:23 +00:00
parent f2c696f016
commit e8cd3f2491

View File

@ -72,7 +72,7 @@ static void PrintOps(Instruction *I, const SmallVectorImpl<ValueEntry> &Ops) {
} }
} }
#endif #endif
namespace { namespace {
/// \brief Utility class representing a base and exponent pair which form one /// \brief Utility class representing a base and exponent pair which form one
/// factor of some product. /// factor of some product.
@ -148,7 +148,7 @@ namespace {
void LinearizeExpr(BinaryOperator *I); void LinearizeExpr(BinaryOperator *I);
Value *RemoveFactorFromExpression(Value *V, Value *Factor); Value *RemoveFactorFromExpression(Value *V, Value *Factor);
void ReassociateInst(BasicBlock::iterator &BBI); void ReassociateInst(BasicBlock::iterator &BBI);
void RemoveDeadBinaryOp(Value *V); void RemoveDeadBinaryOp(Value *V);
}; };
} }
@ -164,16 +164,15 @@ void Reassociate::RemoveDeadBinaryOp(Value *V) {
Instruction *Op = dyn_cast<Instruction>(V); Instruction *Op = dyn_cast<Instruction>(V);
if (!Op || !isa<BinaryOperator>(Op)) if (!Op || !isa<BinaryOperator>(Op))
return; return;
Value *LHS = Op->getOperand(0), *RHS = Op->getOperand(1); Value *LHS = Op->getOperand(0), *RHS = Op->getOperand(1);
ValueRankMap.erase(Op); ValueRankMap.erase(Op);
DeadInsts.push_back(Op); DeadInsts.push_back(Op);
RemoveDeadBinaryOp(LHS); RemoveDeadBinaryOp(LHS);
RemoveDeadBinaryOp(RHS); RemoveDeadBinaryOp(RHS);
} }
static bool isUnmovableInstruction(Instruction *I) { static bool isUnmovableInstruction(Instruction *I) {
if (I->getOpcode() == Instruction::PHI || if (I->getOpcode() == Instruction::PHI ||
I->getOpcode() == Instruction::Alloca || I->getOpcode() == Instruction::Alloca ||
@ -181,7 +180,7 @@ static bool isUnmovableInstruction(Instruction *I) {
I->getOpcode() == Instruction::Invoke || I->getOpcode() == Instruction::Invoke ||
(I->getOpcode() == Instruction::Call && (I->getOpcode() == Instruction::Call &&
!isa<DbgInfoIntrinsic>(I)) || !isa<DbgInfoIntrinsic>(I)) ||
I->getOpcode() == Instruction::UDiv || I->getOpcode() == Instruction::UDiv ||
I->getOpcode() == Instruction::SDiv || I->getOpcode() == Instruction::SDiv ||
I->getOpcode() == Instruction::FDiv || I->getOpcode() == Instruction::FDiv ||
I->getOpcode() == Instruction::URem || I->getOpcode() == Instruction::URem ||
@ -305,7 +304,6 @@ void Reassociate::LinearizeExpr(BinaryOperator *I) {
LinearizeExpr(I); LinearizeExpr(I);
} }
/// LinearizeExprTree - Given an associative binary expression tree, traverse /// LinearizeExprTree - Given an associative binary expression tree, traverse
/// all of the uses putting it into canonical form. This forces a left-linear /// all of the uses putting it into canonical form. This forces a left-linear
/// form of the expression (((a+b)+c)+d), and collects information about the /// form of the expression (((a+b)+c)+d), and collects information about the
@ -343,13 +341,13 @@ void Reassociate::LinearizeExprTree(BinaryOperator *I,
// such, just remember these operands and their rank. // such, just remember these operands and their rank.
Ops.push_back(ValueEntry(getRank(LHS), LHS)); Ops.push_back(ValueEntry(getRank(LHS), LHS));
Ops.push_back(ValueEntry(getRank(RHS), RHS)); Ops.push_back(ValueEntry(getRank(RHS), RHS));
// Clear the leaves out. // Clear the leaves out.
I->setOperand(0, UndefValue::get(I->getType())); I->setOperand(0, UndefValue::get(I->getType()));
I->setOperand(1, UndefValue::get(I->getType())); I->setOperand(1, UndefValue::get(I->getType()));
return; return;
} }
// Turn X+(Y+Z) -> (Y+Z)+X // Turn X+(Y+Z) -> (Y+Z)+X
std::swap(LHSBO, RHSBO); std::swap(LHSBO, RHSBO);
std::swap(LHS, RHS); std::swap(LHS, RHS);
@ -379,7 +377,7 @@ void Reassociate::LinearizeExprTree(BinaryOperator *I,
// Remember the RHS operand and its rank. // Remember the RHS operand and its rank.
Ops.push_back(ValueEntry(getRank(RHS), RHS)); Ops.push_back(ValueEntry(getRank(RHS), RHS));
// Clear the RHS leaf out. // Clear the RHS leaf out.
I->setOperand(1, UndefValue::get(I->getType())); I->setOperand(1, UndefValue::get(I->getType()));
} }
@ -406,7 +404,7 @@ void Reassociate::RewriteExprTree(BinaryOperator *I,
DEBUG(dbgs() << "TO: " << *I << '\n'); DEBUG(dbgs() << "TO: " << *I << '\n');
MadeChange = true; MadeChange = true;
++NumChanged; ++NumChanged;
// If we reassociated a tree to fewer operands (e.g. (1+a+2) -> (a+3) // If we reassociated a tree to fewer operands (e.g. (1+a+2) -> (a+3)
// delete the extra, now dead, nodes. // delete the extra, now dead, nodes.
RemoveDeadBinaryOp(OldLHS); RemoveDeadBinaryOp(OldLHS);
@ -427,28 +425,25 @@ void Reassociate::RewriteExprTree(BinaryOperator *I,
MadeChange = true; MadeChange = true;
++NumChanged; ++NumChanged;
} }
BinaryOperator *LHS = cast<BinaryOperator>(I->getOperand(0)); BinaryOperator *LHS = cast<BinaryOperator>(I->getOperand(0));
assert(LHS->getOpcode() == I->getOpcode() && assert(LHS->getOpcode() == I->getOpcode() &&
"Improper expression tree!"); "Improper expression tree!");
// Compactify the tree instructions together with each other to guarantee // Compactify the tree instructions together with each other to guarantee
// that the expression tree is dominated by all of Ops. // that the expression tree is dominated by all of Ops.
LHS->moveBefore(I); LHS->moveBefore(I);
RewriteExprTree(LHS, Ops, i+1); RewriteExprTree(LHS, Ops, i+1);
} }
/// NegateValue - Insert instructions before the instruction pointed to by BI,
/// that computes the negative version of the value specified. The negative
// NegateValue - Insert instructions before the instruction pointed to by BI, /// version of the value is returned, and BI is left pointing at the instruction
// that computes the negative version of the value specified. The negative /// that should be processed next by the reassociation pass.
// 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) { static Value *NegateValue(Value *V, Instruction *BI) {
if (Constant *C = dyn_cast<Constant>(V)) if (Constant *C = dyn_cast<Constant>(V))
return ConstantExpr::getNeg(C); return ConstantExpr::getNeg(C);
// We are trying to expose opportunity for reassociation. One of the things // 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 // that we want to do to achieve this is to push a negation as deep into an
// expression chain as possible, to expose the add instructions. In practice, // expression chain as possible, to expose the add instructions. In practice,
@ -466,14 +461,14 @@ static Value *NegateValue(Value *V, Instruction *BI) {
// We must move the add instruction here, because the neg instructions do // We must move the add instruction here, because the neg instructions do
// not dominate the old add instruction in general. By moving it, we are // not dominate the old add instruction in general. By moving it, we are
// assured that the neg instructions we just inserted dominate the // assured that the neg instructions we just inserted dominate the
// instruction we are about to insert after them. // instruction we are about to insert after them.
// //
I->moveBefore(BI); I->moveBefore(BI);
I->setName(I->getName()+".neg"); I->setName(I->getName()+".neg");
return I; return I;
} }
// Okay, we need to materialize a negated version of V with an instruction. // Okay, we need to materialize a negated version of V with an instruction.
// Scan the use lists of V to see if we have one already. // Scan the use lists of V to see if we have one already.
for (Value::use_iterator UI = V->use_begin(), E = V->use_end(); UI != E;++UI){ for (Value::use_iterator UI = V->use_begin(), E = V->use_end(); UI != E;++UI){
@ -489,7 +484,7 @@ static Value *NegateValue(Value *V, Instruction *BI) {
// Verify that the negate is in this function, V might be a constant expr. // Verify that the negate is in this function, V might be a constant expr.
if (TheNeg->getParent()->getParent() != BI->getParent()->getParent()) if (TheNeg->getParent()->getParent() != BI->getParent()->getParent())
continue; continue;
BasicBlock::iterator InsertPt; BasicBlock::iterator InsertPt;
if (Instruction *InstInput = dyn_cast<Instruction>(V)) { if (Instruction *InstInput = dyn_cast<Instruction>(V)) {
if (InvokeInst *II = dyn_cast<InvokeInst>(InstInput)) { if (InvokeInst *II = dyn_cast<InvokeInst>(InstInput)) {
@ -517,7 +512,7 @@ static bool ShouldBreakUpSubtract(Instruction *Sub) {
// If this is a negation, we can't split it up! // If this is a negation, we can't split it up!
if (BinaryOperator::isNeg(Sub)) if (BinaryOperator::isNeg(Sub))
return false; return false;
// Don't bother to break this up unless either the LHS is an associable add or // Don't bother to break this up unless either the LHS is an associable add or
// subtract or if this is only used by one. // subtract or if this is only used by one.
if (isReassociableOp(Sub->getOperand(0), Instruction::Add) || if (isReassociableOp(Sub->getOperand(0), Instruction::Add) ||
@ -526,11 +521,11 @@ static bool ShouldBreakUpSubtract(Instruction *Sub) {
if (isReassociableOp(Sub->getOperand(1), Instruction::Add) || if (isReassociableOp(Sub->getOperand(1), Instruction::Add) ||
isReassociableOp(Sub->getOperand(1), Instruction::Sub)) isReassociableOp(Sub->getOperand(1), Instruction::Sub))
return true; return true;
if (Sub->hasOneUse() && if (Sub->hasOneUse() &&
(isReassociableOp(Sub->use_back(), Instruction::Add) || (isReassociableOp(Sub->use_back(), Instruction::Add) ||
isReassociableOp(Sub->use_back(), Instruction::Sub))) isReassociableOp(Sub->use_back(), Instruction::Sub)))
return true; return true;
return false; return false;
} }
@ -568,12 +563,12 @@ static Instruction *ConvertShiftToMul(Instruction *Shl,
// If an operand of this shift is a reassociable multiply, or if the shift // If an operand of this shift is a reassociable multiply, or if the shift
// is used by a reassociable multiply or add, turn into a multiply. // is used by a reassociable multiply or add, turn into a multiply.
if (isReassociableOp(Shl->getOperand(0), Instruction::Mul) || if (isReassociableOp(Shl->getOperand(0), Instruction::Mul) ||
(Shl->hasOneUse() && (Shl->hasOneUse() &&
(isReassociableOp(Shl->use_back(), Instruction::Mul) || (isReassociableOp(Shl->use_back(), Instruction::Mul) ||
isReassociableOp(Shl->use_back(), Instruction::Add)))) { isReassociableOp(Shl->use_back(), Instruction::Add)))) {
Constant *MulCst = ConstantInt::get(Shl->getType(), 1); Constant *MulCst = ConstantInt::get(Shl->getType(), 1);
MulCst = ConstantExpr::getShl(MulCst, cast<Constant>(Shl->getOperand(1))); MulCst = ConstantExpr::getShl(MulCst, cast<Constant>(Shl->getOperand(1)));
Instruction *Mul = Instruction *Mul =
BinaryOperator::CreateMul(Shl->getOperand(0), MulCst, "", Shl); BinaryOperator::CreateMul(Shl->getOperand(0), MulCst, "", Shl);
ValueRankMap.erase(Shl); ValueRankMap.erase(Shl);
@ -586,9 +581,10 @@ static Instruction *ConvertShiftToMul(Instruction *Shl,
return 0; return 0;
} }
// Scan backwards and forwards among values with the same rank as element i to /// FindInOperandList - Scan backwards and forwards among values with the same
// see if X exists. If X does not exist, return i. This is useful when /// rank as element i to see if X exists. If X does not exist, return i. This
// scanning for 'x' when we see '-x' because they both get the same rank. /// is useful when scanning for 'x' when we see '-x' because they both get the
/// same rank.
static unsigned FindInOperandList(SmallVectorImpl<ValueEntry> &Ops, unsigned i, static unsigned FindInOperandList(SmallVectorImpl<ValueEntry> &Ops, unsigned i,
Value *X) { Value *X) {
unsigned XRank = Ops[i].Rank; unsigned XRank = Ops[i].Rank;
@ -608,20 +604,20 @@ static unsigned FindInOperandList(SmallVectorImpl<ValueEntry> &Ops, unsigned i,
static Value *EmitAddTreeOfValues(Instruction *I, static Value *EmitAddTreeOfValues(Instruction *I,
SmallVectorImpl<WeakVH> &Ops){ SmallVectorImpl<WeakVH> &Ops){
if (Ops.size() == 1) return Ops.back(); if (Ops.size() == 1) return Ops.back();
Value *V1 = Ops.back(); Value *V1 = Ops.back();
Ops.pop_back(); Ops.pop_back();
Value *V2 = EmitAddTreeOfValues(I, Ops); Value *V2 = EmitAddTreeOfValues(I, Ops);
return BinaryOperator::CreateAdd(V2, V1, "tmp", I); return BinaryOperator::CreateAdd(V2, V1, "tmp", I);
} }
/// RemoveFactorFromExpression - If V is an expression tree that is a /// RemoveFactorFromExpression - If V is an expression tree that is a
/// multiplication sequence, and if this sequence contains a multiply by Factor, /// multiplication sequence, and if this sequence contains a multiply by Factor,
/// remove Factor from the tree and return the new tree. /// remove Factor from the tree and return the new tree.
Value *Reassociate::RemoveFactorFromExpression(Value *V, Value *Factor) { Value *Reassociate::RemoveFactorFromExpression(Value *V, Value *Factor) {
BinaryOperator *BO = isReassociableOp(V, Instruction::Mul); BinaryOperator *BO = isReassociableOp(V, Instruction::Mul);
if (!BO) return 0; if (!BO) return 0;
SmallVector<ValueEntry, 8> Factors; SmallVector<ValueEntry, 8> Factors;
LinearizeExprTree(BO, Factors); LinearizeExprTree(BO, Factors);
@ -633,7 +629,7 @@ Value *Reassociate::RemoveFactorFromExpression(Value *V, Value *Factor) {
Factors.erase(Factors.begin()+i); Factors.erase(Factors.begin()+i);
break; break;
} }
// If this is a negative version of this factor, remove it. // If this is a negative version of this factor, remove it.
if (ConstantInt *FC1 = dyn_cast<ConstantInt>(Factor)) if (ConstantInt *FC1 = dyn_cast<ConstantInt>(Factor))
if (ConstantInt *FC2 = dyn_cast<ConstantInt>(Factors[i].Op)) if (ConstantInt *FC2 = dyn_cast<ConstantInt>(Factors[i].Op))
@ -643,15 +639,15 @@ Value *Reassociate::RemoveFactorFromExpression(Value *V, Value *Factor) {
break; break;
} }
} }
if (!FoundFactor) { if (!FoundFactor) {
// Make sure to restore the operands to the expression tree. // Make sure to restore the operands to the expression tree.
RewriteExprTree(BO, Factors); RewriteExprTree(BO, Factors);
return 0; return 0;
} }
BasicBlock::iterator InsertPt = BO; ++InsertPt; BasicBlock::iterator InsertPt = BO; ++InsertPt;
// If this was just a single multiply, remove the multiply and return the only // If this was just a single multiply, remove the multiply and return the only
// remaining operand. // remaining operand.
if (Factors.size() == 1) { if (Factors.size() == 1) {
@ -662,10 +658,10 @@ Value *Reassociate::RemoveFactorFromExpression(Value *V, Value *Factor) {
RewriteExprTree(BO, Factors); RewriteExprTree(BO, Factors);
V = BO; V = BO;
} }
if (NeedsNegate) if (NeedsNegate)
V = BinaryOperator::CreateNeg(V, "neg", InsertPt); V = BinaryOperator::CreateNeg(V, "neg", InsertPt);
return V; return V;
} }
@ -684,7 +680,7 @@ static void FindSingleUseMultiplyFactors(Value *V,
Factors.push_back(V); Factors.push_back(V);
return; return;
} }
// If this value has a single use because it is another input to the add // If this value has a single use because it is another input to the add
// tree we're reassociating and we dropped its use, it actually has two // tree we're reassociating and we dropped its use, it actually has two
// uses and we can't factor it. // uses and we can't factor it.
@ -695,8 +691,8 @@ static void FindSingleUseMultiplyFactors(Value *V,
return; return;
} }
} }
// Otherwise, add the LHS and RHS to the list of factors. // Otherwise, add the LHS and RHS to the list of factors.
FindSingleUseMultiplyFactors(BO->getOperand(1), Factors, Ops, false); FindSingleUseMultiplyFactors(BO->getOperand(1), Factors, Ops, false);
FindSingleUseMultiplyFactors(BO->getOperand(0), Factors, Ops, false); FindSingleUseMultiplyFactors(BO->getOperand(0), Factors, Ops, false);
@ -719,12 +715,12 @@ static Value *OptimizeAndOrXor(unsigned Opcode,
if (FoundX != i) { if (FoundX != i) {
if (Opcode == Instruction::And) // ...&X&~X = 0 if (Opcode == Instruction::And) // ...&X&~X = 0
return Constant::getNullValue(X->getType()); return Constant::getNullValue(X->getType());
if (Opcode == Instruction::Or) // ...|X|~X = -1 if (Opcode == Instruction::Or) // ...|X|~X = -1
return Constant::getAllOnesValue(X->getType()); return Constant::getAllOnesValue(X->getType());
} }
} }
// Next, check for duplicate pairs of values, which we assume are next to // Next, check for duplicate pairs of values, which we assume are next to
// each other, due to our sorting criteria. // each other, due to our sorting criteria.
assert(i < Ops.size()); assert(i < Ops.size());
@ -736,12 +732,12 @@ static Value *OptimizeAndOrXor(unsigned Opcode,
++NumAnnihil; ++NumAnnihil;
continue; continue;
} }
// Drop pairs of values for Xor. // Drop pairs of values for Xor.
assert(Opcode == Instruction::Xor); assert(Opcode == Instruction::Xor);
if (e == 2) if (e == 2)
return Constant::getNullValue(Ops[0].Op->getType()); return Constant::getNullValue(Ops[0].Op->getType());
// Y ^ X^X -> Y // Y ^ X^X -> Y
Ops.erase(Ops.begin()+i, Ops.begin()+i+2); Ops.erase(Ops.begin()+i, Ops.begin()+i+2);
i -= 1; e -= 2; i -= 1; e -= 2;
@ -774,46 +770,46 @@ Value *Reassociate::OptimizeAdd(Instruction *I,
Ops.erase(Ops.begin()+i); Ops.erase(Ops.begin()+i);
++NumFound; ++NumFound;
} while (i != Ops.size() && Ops[i].Op == TheOp); } while (i != Ops.size() && Ops[i].Op == TheOp);
DEBUG(errs() << "\nFACTORING [" << NumFound << "]: " << *TheOp << '\n'); DEBUG(errs() << "\nFACTORING [" << NumFound << "]: " << *TheOp << '\n');
++NumFactor; ++NumFactor;
// Insert a new multiply. // Insert a new multiply.
Value *Mul = ConstantInt::get(cast<IntegerType>(I->getType()), NumFound); Value *Mul = ConstantInt::get(cast<IntegerType>(I->getType()), NumFound);
Mul = BinaryOperator::CreateMul(TheOp, Mul, "factor", I); Mul = BinaryOperator::CreateMul(TheOp, Mul, "factor", I);
// Now that we have inserted a multiply, optimize it. This allows us to // Now that we have inserted a multiply, optimize it. This allows us to
// handle cases that require multiple factoring steps, such as this: // handle cases that require multiple factoring steps, such as this:
// (X*2) + (X*2) + (X*2) -> (X*2)*3 -> X*6 // (X*2) + (X*2) + (X*2) -> (X*2)*3 -> X*6
RedoInsts.push_back(Mul); RedoInsts.push_back(Mul);
// If every add operand was a duplicate, return the multiply. // If every add operand was a duplicate, return the multiply.
if (Ops.empty()) if (Ops.empty())
return Mul; return Mul;
// Otherwise, we had some input that didn't have the dupe, such as // Otherwise, we had some input that didn't have the dupe, such as
// "A + A + B" -> "A*2 + B". Add the new multiply to the list of // "A + A + B" -> "A*2 + B". Add the new multiply to the list of
// things being added by this operation. // things being added by this operation.
Ops.insert(Ops.begin(), ValueEntry(getRank(Mul), Mul)); Ops.insert(Ops.begin(), ValueEntry(getRank(Mul), Mul));
--i; --i;
e = Ops.size(); e = Ops.size();
continue; continue;
} }
// Check for X and -X in the operand list. // Check for X and -X in the operand list.
if (!BinaryOperator::isNeg(TheOp)) if (!BinaryOperator::isNeg(TheOp))
continue; continue;
Value *X = BinaryOperator::getNegArgument(TheOp); Value *X = BinaryOperator::getNegArgument(TheOp);
unsigned FoundX = FindInOperandList(Ops, i, X); unsigned FoundX = FindInOperandList(Ops, i, X);
if (FoundX == i) if (FoundX == i)
continue; continue;
// Remove X and -X from the operand list. // Remove X and -X from the operand list.
if (Ops.size() == 2) if (Ops.size() == 2)
return Constant::getNullValue(X->getType()); return Constant::getNullValue(X->getType());
Ops.erase(Ops.begin()+i); Ops.erase(Ops.begin()+i);
if (i < FoundX) if (i < FoundX)
--FoundX; --FoundX;
@ -824,14 +820,14 @@ Value *Reassociate::OptimizeAdd(Instruction *I,
--i; // Revisit element. --i; // Revisit element.
e -= 2; // Removed two elements. e -= 2; // Removed two elements.
} }
// Scan the operand list, checking to see if there are any common factors // Scan the operand list, checking to see if there are any common factors
// between operands. Consider something like A*A+A*B*C+D. We would like to // between operands. Consider something like A*A+A*B*C+D. We would like to
// reassociate this to A*(A+B*C)+D, which reduces the number of multiplies. // reassociate this to A*(A+B*C)+D, which reduces the number of multiplies.
// To efficiently find this, we count the number of times a factor occurs // To efficiently find this, we count the number of times a factor occurs
// for any ADD operands that are MULs. // for any ADD operands that are MULs.
DenseMap<Value*, unsigned> FactorOccurrences; DenseMap<Value*, unsigned> FactorOccurrences;
// Keep track of each multiply we see, to avoid triggering on (X*4)+(X*4) // Keep track of each multiply we see, to avoid triggering on (X*4)+(X*4)
// where they are actually the same multiply. // where they are actually the same multiply.
unsigned MaxOcc = 0; unsigned MaxOcc = 0;
@ -840,21 +836,21 @@ Value *Reassociate::OptimizeAdd(Instruction *I,
BinaryOperator *BOp = dyn_cast<BinaryOperator>(Ops[i].Op); BinaryOperator *BOp = dyn_cast<BinaryOperator>(Ops[i].Op);
if (BOp == 0 || BOp->getOpcode() != Instruction::Mul || !BOp->use_empty()) if (BOp == 0 || BOp->getOpcode() != Instruction::Mul || !BOp->use_empty())
continue; continue;
// Compute all of the factors of this added value. // Compute all of the factors of this added value.
SmallVector<Value*, 8> Factors; SmallVector<Value*, 8> Factors;
FindSingleUseMultiplyFactors(BOp, Factors, Ops, true); FindSingleUseMultiplyFactors(BOp, Factors, Ops, true);
assert(Factors.size() > 1 && "Bad linearize!"); assert(Factors.size() > 1 && "Bad linearize!");
// Add one to FactorOccurrences for each unique factor in this op. // Add one to FactorOccurrences for each unique factor in this op.
SmallPtrSet<Value*, 8> Duplicates; SmallPtrSet<Value*, 8> Duplicates;
for (unsigned i = 0, e = Factors.size(); i != e; ++i) { for (unsigned i = 0, e = Factors.size(); i != e; ++i) {
Value *Factor = Factors[i]; Value *Factor = Factors[i];
if (!Duplicates.insert(Factor)) continue; if (!Duplicates.insert(Factor)) continue;
unsigned Occ = ++FactorOccurrences[Factor]; unsigned Occ = ++FactorOccurrences[Factor];
if (Occ > MaxOcc) { MaxOcc = Occ; MaxOccVal = Factor; } if (Occ > MaxOcc) { MaxOcc = Occ; MaxOccVal = Factor; }
// If Factor is a negative constant, add the negated value as a factor // If Factor is a negative constant, add the negated value as a factor
// because we can percolate the negate out. Watch for minint, which // because we can percolate the negate out. Watch for minint, which
// cannot be positivified. // cannot be positivified.
@ -863,13 +859,13 @@ Value *Reassociate::OptimizeAdd(Instruction *I,
Factor = ConstantInt::get(CI->getContext(), -CI->getValue()); Factor = ConstantInt::get(CI->getContext(), -CI->getValue());
assert(!Duplicates.count(Factor) && assert(!Duplicates.count(Factor) &&
"Shouldn't have two constant factors, missed a canonicalize"); "Shouldn't have two constant factors, missed a canonicalize");
unsigned Occ = ++FactorOccurrences[Factor]; unsigned Occ = ++FactorOccurrences[Factor];
if (Occ > MaxOcc) { MaxOcc = Occ; MaxOccVal = Factor; } if (Occ > MaxOcc) { MaxOcc = Occ; MaxOccVal = Factor; }
} }
} }
} }
// If any factor occurred more than one time, we can pull it out. // If any factor occurred more than one time, we can pull it out.
if (MaxOcc > 1) { if (MaxOcc > 1) {
DEBUG(errs() << "\nFACTORING [" << MaxOcc << "]: " << *MaxOccVal << '\n'); DEBUG(errs() << "\nFACTORING [" << MaxOcc << "]: " << *MaxOccVal << '\n');
@ -877,7 +873,7 @@ Value *Reassociate::OptimizeAdd(Instruction *I,
// Create a new instruction that uses the MaxOccVal twice. If we don't do // Create a new instruction that uses the MaxOccVal twice. If we don't do
// this, we could otherwise run into situations where removing a factor // this, we could otherwise run into situations where removing a factor
// from an expression will drop a use of maxocc, and this can cause // from an expression will drop a use of maxocc, and this can cause
// RemoveFactorFromExpression on successive values to behave differently. // RemoveFactorFromExpression on successive values to behave differently.
Instruction *DummyInst = BinaryOperator::CreateAdd(MaxOccVal, MaxOccVal); Instruction *DummyInst = BinaryOperator::CreateAdd(MaxOccVal, MaxOccVal);
SmallVector<WeakVH, 4> NewMulOps; SmallVector<WeakVH, 4> NewMulOps;
@ -886,7 +882,7 @@ Value *Reassociate::OptimizeAdd(Instruction *I,
BinaryOperator *BOp = dyn_cast<BinaryOperator>(Ops[i].Op); BinaryOperator *BOp = dyn_cast<BinaryOperator>(Ops[i].Op);
if (BOp == 0 || BOp->getOpcode() != Instruction::Mul || !BOp->use_empty()) if (BOp == 0 || BOp->getOpcode() != Instruction::Mul || !BOp->use_empty())
continue; continue;
if (Value *V = RemoveFactorFromExpression(Ops[i].Op, MaxOccVal)) { if (Value *V = RemoveFactorFromExpression(Ops[i].Op, MaxOccVal)) {
// The factorized operand may occur several times. Convert them all in // The factorized operand may occur several times. Convert them all in
// one fell swoop. // one fell swoop.
@ -900,7 +896,7 @@ Value *Reassociate::OptimizeAdd(Instruction *I,
--i; --i;
} }
} }
// No need for extra uses anymore. // No need for extra uses anymore.
delete DummyInst; delete DummyInst;
@ -920,18 +916,18 @@ Value *Reassociate::OptimizeAdd(Instruction *I,
// Rerun associate on the multiply in case the inner expression turned into // Rerun associate on the multiply in case the inner expression turned into
// a multiply. We want to make sure that we keep things in canonical form. // a multiply. We want to make sure that we keep things in canonical form.
V2 = ReassociateExpression(cast<BinaryOperator>(V2)); V2 = ReassociateExpression(cast<BinaryOperator>(V2));
// If every add operand included the factor (e.g. "A*B + A*C"), then the // If every add operand included the factor (e.g. "A*B + A*C"), then the
// entire result expression is just the multiply "A*(B+C)". // entire result expression is just the multiply "A*(B+C)".
if (Ops.empty()) if (Ops.empty())
return V2; return V2;
// Otherwise, we had some input that didn't have the factor, such as // Otherwise, we had some input that didn't have the factor, such as
// "A*B + A*C + D" -> "A*(B+C) + D". Add the new multiply to the list of // "A*B + A*C + D" -> "A*(B+C) + D". Add the new multiply to the list of
// things being added by this operation. // things being added by this operation.
Ops.insert(Ops.begin(), ValueEntry(getRank(V2), V2)); Ops.insert(Ops.begin(), ValueEntry(getRank(V2), V2));
} }
return 0; return 0;
} }
@ -1136,7 +1132,7 @@ Value *Reassociate::OptimizeExpression(BinaryOperator *I,
if (Ops.size() == 1) return Ops[0].Op; if (Ops.size() == 1) return Ops[0].Op;
unsigned Opcode = I->getOpcode(); unsigned Opcode = I->getOpcode();
if (Constant *V1 = dyn_cast<Constant>(Ops[Ops.size()-2].Op)) if (Constant *V1 = dyn_cast<Constant>(Ops[Ops.size()-2].Op))
if (Constant *V2 = dyn_cast<Constant>(Ops.back().Op)) { if (Constant *V2 = dyn_cast<Constant>(Ops.back().Op)) {
Ops.pop_back(); Ops.pop_back();
@ -1159,7 +1155,7 @@ Value *Reassociate::OptimizeExpression(BinaryOperator *I,
++NumAnnihil; ++NumAnnihil;
return CstVal; return CstVal;
} }
if (cast<ConstantInt>(CstVal)->isOne()) if (cast<ConstantInt>(CstVal)->isOne())
Ops.pop_back(); // X * 1 -> X Ops.pop_back(); // X * 1 -> X
break; break;
@ -1203,7 +1199,6 @@ Value *Reassociate::OptimizeExpression(BinaryOperator *I,
return 0; return 0;
} }
/// ReassociateInst - Inspect and reassociate the instruction at the /// ReassociateInst - Inspect and reassociate the instruction at the
/// given position, post-incrementing the position. /// given position, post-incrementing the position.
void Reassociate::ReassociateInst(BasicBlock::iterator &BBI) { void Reassociate::ReassociateInst(BasicBlock::iterator &BBI) {
@ -1216,7 +1211,7 @@ void Reassociate::ReassociateInst(BasicBlock::iterator &BBI) {
} }
// Reject cases where it is pointless to do this. // Reject cases where it is pointless to do this.
if (!isa<BinaryOperator>(BI) || BI->getType()->isFloatingPointTy() || if (!isa<BinaryOperator>(BI) || BI->getType()->isFloatingPointTy() ||
BI->getType()->isVectorTy()) BI->getType()->isVectorTy())
return; // Floating point ops are not associative. return; // Floating point ops are not associative.
@ -1260,7 +1255,7 @@ void Reassociate::ReassociateInst(BasicBlock::iterator &BBI) {
if (I->hasOneUse() && isReassociableOp(I->use_back(), I->getOpcode())) if (I->hasOneUse() && isReassociableOp(I->use_back(), I->getOpcode()))
return; return;
// If this is an add tree that is used by a sub instruction, ignore it // If this is an add tree that is used by a sub instruction, ignore it
// until we process the subtract. // until we process the subtract.
if (I->hasOneUse() && I->getOpcode() == Instruction::Add && if (I->hasOneUse() && I->getOpcode() == Instruction::Add &&
cast<Instruction>(I->use_back())->getOpcode() == Instruction::Sub) cast<Instruction>(I->use_back())->getOpcode() == Instruction::Sub)
@ -1270,14 +1265,14 @@ void Reassociate::ReassociateInst(BasicBlock::iterator &BBI) {
} }
Value *Reassociate::ReassociateExpression(BinaryOperator *I) { Value *Reassociate::ReassociateExpression(BinaryOperator *I) {
// First, walk the expression tree, linearizing the tree, collecting the // First, walk the expression tree, linearizing the tree, collecting the
// operand information. // operand information.
SmallVector<ValueEntry, 8> Ops; SmallVector<ValueEntry, 8> Ops;
LinearizeExprTree(I, Ops); LinearizeExprTree(I, Ops);
DEBUG(dbgs() << "RAIn:\t"; PrintOps(I, Ops); dbgs() << '\n'); DEBUG(dbgs() << "RAIn:\t"; PrintOps(I, Ops); dbgs() << '\n');
// Now that we have linearized the tree to a list and have gathered all of // Now that we have linearized the tree to a list and have gathered all of
// the operands and their ranks, sort the operands by their rank. Use a // the operands and their ranks, sort the operands by their rank. Use a
// stable_sort so that values with equal ranks will have their relative // stable_sort so that values with equal ranks will have their relative
@ -1285,7 +1280,7 @@ Value *Reassociate::ReassociateExpression(BinaryOperator *I) {
// this sorts so that the highest ranking values end up at the beginning of // this sorts so that the highest ranking values end up at the beginning of
// the vector. // the vector.
std::stable_sort(Ops.begin(), Ops.end()); std::stable_sort(Ops.begin(), Ops.end());
// OptimizeExpression - Now that we have the expression tree in a convenient // OptimizeExpression - Now that we have the expression tree in a convenient
// sorted form, optimize it globally if possible. // sorted form, optimize it globally if possible.
if (Value *V = OptimizeExpression(I, Ops)) { if (Value *V = OptimizeExpression(I, Ops)) {
@ -1299,7 +1294,7 @@ Value *Reassociate::ReassociateExpression(BinaryOperator *I) {
++NumAnnihil; ++NumAnnihil;
return V; return V;
} }
// We want to sink immediates as deeply as possible except in the case where // We want to sink immediates as deeply as possible except in the case where
// this is a multiply tree used only by an add, and the immediate is a -1. // this is a multiply tree used only by an add, and the immediate is a -1.
// In this case we reassociate to put the negation on the outside so that we // In this case we reassociate to put the negation on the outside so that we
@ -1311,9 +1306,9 @@ Value *Reassociate::ReassociateExpression(BinaryOperator *I) {
ValueEntry Tmp = Ops.pop_back_val(); ValueEntry Tmp = Ops.pop_back_val();
Ops.insert(Ops.begin(), Tmp); Ops.insert(Ops.begin(), Tmp);
} }
DEBUG(dbgs() << "RAOut:\t"; PrintOps(I, Ops); dbgs() << '\n'); DEBUG(dbgs() << "RAOut:\t"; PrintOps(I, Ops); dbgs() << '\n');
if (Ops.size() == 1) { if (Ops.size() == 1) {
// This expression tree simplified to something that isn't a tree, // This expression tree simplified to something that isn't a tree,
// eliminate it. // eliminate it.
@ -1323,14 +1318,13 @@ Value *Reassociate::ReassociateExpression(BinaryOperator *I) {
RemoveDeadBinaryOp(I); RemoveDeadBinaryOp(I);
return Ops[0].Op; return Ops[0].Op;
} }
// Now that we ordered and optimized the expressions, splat them back into // Now that we ordered and optimized the expressions, splat them back into
// the expression tree, removing any unneeded nodes. // the expression tree, removing any unneeded nodes.
RewriteExprTree(I, Ops); RewriteExprTree(I, Ops);
return I; return I;
} }
bool Reassociate::runOnFunction(Function &F) { bool Reassociate::runOnFunction(Function &F) {
// Recalculate the rank map for F // Recalculate the rank map for F
BuildRankMap(F); BuildRankMap(F);
@ -1358,4 +1352,3 @@ bool Reassociate::runOnFunction(Function &F) {
ValueRankMap.clear(); ValueRankMap.clear();
return MadeChange; return MadeChange;
} }