//
// The LLVM Compiler Infrastructure
//
-// This file was developed by the LLVM research group and is distributed under
-// the University of Illinois Open Source License. See LICENSE.TXT for details.
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
#include "llvm/Pass.h"
#include "llvm/Assembly/Writer.h"
#include "llvm/Support/CFG.h"
+#include "llvm/Support/Compiler.h"
#include "llvm/Support/Debug.h"
#include "llvm/ADT/PostOrderIterator.h"
#include "llvm/ADT/Statistic.h"
#include <algorithm>
+#include <map>
using namespace llvm;
-namespace {
- Statistic NumLinear ("reassociate","Number of insts linearized");
- Statistic NumChanged("reassociate","Number of insts reassociated");
- Statistic NumSwapped("reassociate","Number of insts with operands swapped");
- Statistic NumAnnihil("reassociate","Number of expr tree annihilated");
- Statistic NumFactor ("reassociate","Number of multiplies factored");
+STATISTIC(NumLinear , "Number of insts linearized");
+STATISTIC(NumChanged, "Number of insts reassociated");
+STATISTIC(NumAnnihil, "Number of expr tree annihilated");
+STATISTIC(NumFactor , "Number of multiplies factored");
- struct ValueEntry {
+namespace {
+ struct VISIBILITY_HIDDEN ValueEntry {
unsigned Rank;
Value *Op;
ValueEntry(unsigned R, Value *O) : Rank(R), Op(O) {}
<< "," << Ops[i].Rank;
}
-namespace {
- class Reassociate : public FunctionPass {
+namespace {
+ class VISIBILITY_HIDDEN Reassociate : public FunctionPass {
std::map<BasicBlock*, unsigned> RankMap;
std::map<Value*, unsigned> ValueRankMap;
bool MadeChange;
public:
+ static char ID; // Pass identification, replacement for typeid
+ Reassociate() : FunctionPass((intptr_t)&ID) {}
+
bool runOnFunction(Function &F);
virtual void getAnalysisUsage(AnalysisUsage &AU) const {
void RemoveDeadBinaryOp(Value *V);
};
-
- RegisterPass<Reassociate> X("reassociate", "Reassociate expressions");
}
+char Reassociate::ID = 0;
+static RegisterPass<Reassociate> X("reassociate", "Reassociate expressions");
+
// Public interface to the Reassociate pass
FunctionPass *llvm::createReassociatePass() { return new Reassociate(); }
void Reassociate::RemoveDeadBinaryOp(Value *V) {
- BinaryOperator *BOp = dyn_cast<BinaryOperator>(V);
- if (!BOp || !BOp->use_empty()) return;
+ Instruction *Op = dyn_cast<Instruction>(V);
+ if (!Op || !isa<BinaryOperator>(Op) || !isa<CmpInst>(Op) || !Op->use_empty())
+ return;
- Value *LHS = BOp->getOperand(0), *RHS = BOp->getOperand(1);
+ Value *LHS = Op->getOperand(0), *RHS = Op->getOperand(1);
RemoveDeadBinaryOp(LHS);
RemoveDeadBinaryOp(RHS);
}
// 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.
- if (!I->getType()->isIntegral() ||
+ if (!I->getType()->isInteger() ||
(!BinaryOperator::isNot(I) && !BinaryOperator::isNeg(I)))
++Rank;
/// LowerNegateToMultiply - Replace 0-X with X*-1.
///
static Instruction *LowerNegateToMultiply(Instruction *Neg) {
- Constant *Cst;
- if (Neg->getType()->isFloatingPoint())
- Cst = ConstantFP::get(Neg->getType(), -1);
- else
- Cst = ConstantInt::getAllOnesValue(Neg->getType());
-
- std::string NegName = Neg->getName(); Neg->setName("");
- Instruction *Res = BinaryOperator::createMul(Neg->getOperand(1), Cst, NegName,
- Neg);
+ Constant *Cst = ConstantInt::getAllOnesValue(Neg->getType());
+
+ Instruction *Res = BinaryOperator::CreateMul(Neg->getOperand(1), Cst, "",Neg);
+ Res->takeName(Neg);
Neg->replaceAllUsesWith(Res);
Neg->eraseFromParent();
return Res;
// Insert a 'neg' instruction that subtracts the value from zero to get the
// negation.
//
- return BinaryOperator::createNeg(V, V->getName() + ".neg", BI);
+ return BinaryOperator::CreateNeg(V, V->getName() + ".neg", BI);
+}
+
+/// ShouldBreakUpSubtract - Return true if we should break up this subtract of
+/// X-Y into (X + -Y).
+static bool ShouldBreakUpSubtract(Instruction *Sub) {
+ // If this is a negation, we can't split it up!
+ if (BinaryOperator::isNeg(Sub))
+ return false;
+
+ // 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.
+ if (isReassociableOp(Sub->getOperand(0), Instruction::Add) ||
+ isReassociableOp(Sub->getOperand(0), Instruction::Sub))
+ return true;
+ if (isReassociableOp(Sub->getOperand(1), Instruction::Add) ||
+ isReassociableOp(Sub->getOperand(1), Instruction::Sub))
+ return true;
+ if (Sub->hasOneUse() &&
+ (isReassociableOp(Sub->use_back(), Instruction::Add) ||
+ isReassociableOp(Sub->use_back(), Instruction::Sub)))
+ return true;
+
+ return false;
}
/// BreakUpSubtract - If we have (X-Y), and if either X is an add, or if this is
/// only used by an add, transform this into (X+(0-Y)) to promote better
/// reassociation.
static Instruction *BreakUpSubtract(Instruction *Sub) {
- // Don't bother to break this up unless either the LHS is an associable add or
- // if this is only used by one.
- if (!isReassociableOp(Sub->getOperand(0), Instruction::Add) &&
- !isReassociableOp(Sub->getOperand(1), Instruction::Add) &&
- !(Sub->hasOneUse() &&isReassociableOp(Sub->use_back(), Instruction::Add)))
- return 0;
-
// Convert a subtract into an add and a neg instruction... so that sub
// instructions can be commuted with other add instructions...
//
// Calculate the negative value of Operand 1 of the sub instruction...
// and set it as the RHS of the add instruction we just made...
//
- std::string Name = Sub->getName();
- Sub->setName("");
Value *NegVal = NegateValue(Sub->getOperand(1), Sub);
Instruction *New =
- BinaryOperator::createAdd(Sub->getOperand(0), NegVal, Name, Sub);
+ BinaryOperator::CreateAdd(Sub->getOperand(0), NegVal, "", Sub);
+ New->takeName(Sub);
// Everyone now refers to the add instruction.
Sub->replaceAllUsesWith(New);
Constant *MulCst = ConstantInt::get(Shl->getType(), 1);
MulCst = ConstantExpr::getShl(MulCst, cast<Constant>(Shl->getOperand(1)));
- std::string Name = Shl->getName(); Shl->setName("");
- Instruction *Mul = BinaryOperator::createMul(Shl->getOperand(0), MulCst,
- Name, Shl);
+ Instruction *Mul = BinaryOperator::CreateMul(Shl->getOperand(0), MulCst,
+ "", Shl);
+ Mul->takeName(Shl);
Shl->replaceAllUsesWith(Mul);
Shl->eraseFromParent();
return Mul;
Value *V1 = Ops.back();
Ops.pop_back();
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
}
// Check for destructive annihilation due to a constant being used.
- if (ConstantIntegral *CstVal = dyn_cast<ConstantIntegral>(Ops.back().Op))
+ if (ConstantInt *CstVal = dyn_cast<ConstantInt>(Ops.back().Op))
switch (Opcode) {
default: break;
case Instruction::And:
- if (CstVal->isNullValue()) { // ... & 0 -> 0
+ if (CstVal->isZero()) { // ... & 0 -> 0
++NumAnnihil;
return CstVal;
} else if (CstVal->isAllOnesValue()) { // ... & -1 -> ...
}
break;
case Instruction::Mul:
- if (CstVal->isNullValue()) { // ... * 0 -> 0
+ if (CstVal->isZero()) { // ... * 0 -> 0
++NumAnnihil;
return CstVal;
- } else if (cast<ConstantInt>(CstVal)->getZExtValue() == 1) {
+ } else if (cast<ConstantInt>(CstVal)->isOne()) {
Ops.pop_back(); // ... * 1 -> ...
}
break;
// FALLTHROUGH!
case Instruction::Add:
case Instruction::Xor:
- if (CstVal->isNullValue()) // ... [|^+] 0 -> ...
+ if (CstVal->isZero()) // ... [|^+] 0 -> ...
Ops.pop_back();
break;
}
return Constant::getNullValue(X->getType());
} else if (Opcode == Instruction::Or) { // ...|X|~X = -1
++NumAnnihil;
- return ConstantIntegral::getAllOnesValue(X->getType());
+ return ConstantInt::getAllOnesValue(X->getType());
}
}
}
std::map<Value*, unsigned> FactorOccurrences;
unsigned MaxOcc = 0;
Value *MaxOccVal = 0;
- if (!I->getType()->isFloatingPoint()) {
- for (unsigned i = 0, e = Ops.size(); i != e; ++i) {
- if (BinaryOperator *BOp = dyn_cast<BinaryOperator>(Ops[i].Op))
- if (BOp->getOpcode() == Instruction::Mul && BOp->use_empty()) {
- // Compute all of the factors of this added value.
- std::vector<Value*> Factors;
- FindSingleUseMultiplyFactors(BOp, Factors);
- assert(Factors.size() > 1 && "Bad linearize!");
-
- // Add one to FactorOccurrences for each unique factor in this op.
- if (Factors.size() == 2) {
- unsigned Occ = ++FactorOccurrences[Factors[0]];
- if (Occ > MaxOcc) { MaxOcc = Occ; MaxOccVal = Factors[0]; }
- if (Factors[0] != Factors[1]) { // Don't double count A*A.
- Occ = ++FactorOccurrences[Factors[1]];
- if (Occ > MaxOcc) { MaxOcc = Occ; MaxOccVal = Factors[1]; }
+ for (unsigned i = 0, e = Ops.size(); i != e; ++i) {
+ if (BinaryOperator *BOp = dyn_cast<BinaryOperator>(Ops[i].Op)) {
+ if (BOp->getOpcode() == Instruction::Mul && BOp->use_empty()) {
+ // Compute all of the factors of this added value.
+ std::vector<Value*> Factors;
+ FindSingleUseMultiplyFactors(BOp, Factors);
+ assert(Factors.size() > 1 && "Bad linearize!");
+
+ // Add one to FactorOccurrences for each unique factor in this op.
+ if (Factors.size() == 2) {
+ unsigned Occ = ++FactorOccurrences[Factors[0]];
+ if (Occ > MaxOcc) { MaxOcc = Occ; MaxOccVal = Factors[0]; }
+ if (Factors[0] != Factors[1]) { // Don't double count A*A.
+ Occ = ++FactorOccurrences[Factors[1]];
+ if (Occ > MaxOcc) { MaxOcc = Occ; MaxOccVal = Factors[1]; }
+ }
+ } else {
+ std::set<Value*> Duplicates;
+ for (unsigned i = 0, e = Factors.size(); i != e; ++i) {
+ if (Duplicates.insert(Factors[i]).second) {
+ unsigned Occ = ++FactorOccurrences[Factors[i]];
+ if (Occ > MaxOcc) { MaxOcc = Occ; MaxOccVal = Factors[i]; }
}
- } else {
- std::set<Value*> Duplicates;
- for (unsigned i = 0, e = Factors.size(); i != e; ++i)
- if (Duplicates.insert(Factors[i]).second) {
- unsigned Occ = ++FactorOccurrences[Factors[i]];
- if (Occ > MaxOcc) { MaxOcc = Occ; MaxOccVal = Factors[i]; }
- }
}
}
+ }
}
}
// this, we could otherwise run into situations where removing a factor
// from an expression will drop a use of maxocc, and this can cause
// RemoveFactorFromExpression on successive values to behave differently.
- Instruction *DummyInst = BinaryOperator::createAdd(MaxOccVal, MaxOccVal);
+ Instruction *DummyInst = BinaryOperator::CreateAdd(MaxOccVal, MaxOccVal);
std::vector<Value*> NewMulOps;
for (unsigned i = 0, e = Ops.size(); i != e; ++i) {
if (Value *V = RemoveFactorFromExpression(Ops[i].Op, MaxOccVal)) {
unsigned NumAddedValues = NewMulOps.size();
Value *V = EmitAddTreeOfValues(I, NewMulOps);
- Value *V2 = BinaryOperator::createMul(V, MaxOccVal, "tmp", I);
+ Value *V2 = BinaryOperator::CreateMul(V, MaxOccVal, "tmp", I);
// Now that we have inserted V and its sole use, optimize it. This allows
// us to handle cases that require multiple factoring steps, such as this:
++NumFactor;
- if (Ops.size() == 0)
+ if (Ops.empty())
return V2;
// Add the new value to the list of things being added.
}
// Reject cases where it is pointless to do this.
- if (!isa<BinaryOperator>(BI) || BI->getType()->isFloatingPoint() ||
- isa<PackedType>(BI->getType()))
+ if (!isa<BinaryOperator>(BI) || BI->getType()->isFloatingPoint() ||
+ isa<VectorType>(BI->getType()))
continue; // Floating point ops are not associative.
// If this is a subtract instruction which is not already in negate form,
// see if we can convert it to X+-Y.
if (BI->getOpcode() == Instruction::Sub) {
- if (!BinaryOperator::isNeg(BI)) {
- if (Instruction *NI = BreakUpSubtract(BI)) {
- MadeChange = true;
- BI = NI;
- }
- } else {
+ if (ShouldBreakUpSubtract(BI)) {
+ BI = BreakUpSubtract(BI);
+ MadeChange = true;
+ } else if (BinaryOperator::isNeg(BI)) {
// Otherwise, this is a negation. See if the operand is a multiply tree
// and if this is not an inner node of a multiply tree.
if (isReassociableOp(BI->getOperand(1), Instruction::Mul) &&