///
static void PrintOps(Instruction *I, const SmallVectorImpl<ValueEntry> &Ops) {
Module *M = I->getParent()->getParent()->getParent();
- errs() << Instruction::getOpcodeName(I->getOpcode()) << " "
+ dbgs() << Instruction::getOpcodeName(I->getOpcode()) << " "
<< *Ops[0].Op->getType() << '\t';
for (unsigned i = 0, e = Ops.size(); i != e; ++i) {
- errs() << "[ ";
- WriteAsOperand(errs(), Ops[i].Op, false, M);
- errs() << ", #" << Ops[i].Rank << "] ";
+ dbgs() << "[ ";
+ WriteAsOperand(dbgs(), Ops[i].Op, false, M);
+ dbgs() << ", #" << Ops[i].Rank << "] ";
}
}
#endif
bool MadeChange;
public:
static char ID; // Pass identification, replacement for typeid
- Reassociate() : FunctionPass(&ID) {}
+ Reassociate() : FunctionPass(ID) {}
bool runOnFunction(Function &F);
}
char Reassociate::ID = 0;
-static RegisterPass<Reassociate> X("reassociate", "Reassociate expressions");
+INITIALIZE_PASS(Reassociate, "reassociate",
+ "Reassociate expressions", false, false);
// Public interface to the Reassociate pass
FunctionPass *llvm::createReassociatePass() { return new Reassociate(); }
// 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()->isInteger() ||
+ if (!I->getType()->isIntegerTy() ||
(!BinaryOperator::isNot(I) && !BinaryOperator::isNeg(I)))
++Rank;
- //DEBUG(errs() << "Calculated Rank[" << V->getName() << "] = "
+ //DEBUG(dbgs() << "Calculated Rank[" << V->getName() << "] = "
// << Rank << "\n");
return ValueRankMap[I] = Rank;
isReassociableOp(RHS, I->getOpcode()) &&
"Not an expression that needs linearization?");
- DEBUG(errs() << "Linear" << *LHS << '\n' << *RHS << '\n' << *I << '\n');
+ DEBUG(dbgs() << "Linear" << *LHS << '\n' << *RHS << '\n' << *I << '\n');
// Move the RHS instruction to live immediately before I, avoiding breaking
// dominator properties.
++NumLinear;
MadeChange = true;
- DEBUG(errs() << "Linearized: " << *I << '\n');
+ DEBUG(dbgs() << "Linearized: " << *I << '\n');
// If D is part of this expression tree, tail recurse.
if (isReassociableOp(I->getOperand(1), I->getOpcode()))
/// LinearizeExprTree - Given an associative binary expression tree, traverse
/// all of the uses putting it into canonical form. This forces a left-linear
-/// form of the the expression (((a+b)+c)+d), and collects information about the
+/// form of the expression (((a+b)+c)+d), and collects information about the
/// rank of the non-tree operands.
///
/// NOTE: These intentionally destroys the expression tree operands (turning
Success = false;
MadeChange = true;
} else if (RHSBO) {
- // Turn (A+B)+(C+D) -> (((A+B)+C)+D). This guarantees the the RHS is not
+ // Turn (A+B)+(C+D) -> (((A+B)+C)+D). This guarantees the RHS is not
// part of the expression tree.
LinearizeExpr(I);
LHS = LHSBO = cast<BinaryOperator>(I->getOperand(0));
if (I->getOperand(0) != Ops[i].Op ||
I->getOperand(1) != Ops[i+1].Op) {
Value *OldLHS = I->getOperand(0);
- DEBUG(errs() << "RA: " << *I << '\n');
+ DEBUG(dbgs() << "RA: " << *I << '\n');
I->setOperand(0, Ops[i].Op);
I->setOperand(1, Ops[i+1].Op);
- DEBUG(errs() << "TO: " << *I << '\n');
+ DEBUG(dbgs() << "TO: " << *I << '\n');
MadeChange = true;
++NumChanged;
assert(i+2 < Ops.size() && "Ops index out of range!");
if (I->getOperand(1) != Ops[i].Op) {
- DEBUG(errs() << "RA: " << *I << '\n');
+ DEBUG(dbgs() << "RA: " << *I << '\n');
I->setOperand(1, Ops[i].Op);
- DEBUG(errs() << "TO: " << *I << '\n');
+ DEBUG(dbgs() << "TO: " << *I << '\n');
MadeChange = true;
++NumChanged;
}
// 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.
for (Value::use_iterator UI = V->use_begin(), E = V->use_end(); UI != E;++UI){
- if (!BinaryOperator::isNeg(*UI)) continue;
+ User *U = *UI;
+ if (!BinaryOperator::isNeg(U)) continue;
// We found one! Now we have to make sure that the definition dominates
// this use. We do this by moving it to the entry block (if it is a
// non-instruction value) or right after the definition. These negates will
// be zapped by reassociate later, so we don't need much finesse here.
- BinaryOperator *TheNeg = cast<BinaryOperator>(*UI);
+ BinaryOperator *TheNeg = cast<BinaryOperator>(U);
// Verify that the negate is in this function, V might be a constant expr.
if (TheNeg->getParent()->getParent() != BI->getParent()->getParent())
Sub->replaceAllUsesWith(New);
Sub->eraseFromParent();
- DEBUG(errs() << "Negated: " << *New << '\n');
+ DEBUG(dbgs() << "Negated: " << *New << '\n');
return New;
}
/// FindSingleUseMultiplyFactors - If V is a single-use multiply, recursively
/// add its operands as factors, otherwise add V to the list of factors.
+///
+/// Ops is the top-level list of add operands we're trying to factor.
static void FindSingleUseMultiplyFactors(Value *V,
- SmallVectorImpl<Value*> &Factors) {
+ SmallVectorImpl<Value*> &Factors,
+ const SmallVectorImpl<ValueEntry> &Ops,
+ bool IsRoot) {
BinaryOperator *BO;
- if ((!V->hasOneUse() && !V->use_empty()) ||
+ if (!(V->hasOneUse() || V->use_empty()) || // More than one use.
!(BO = dyn_cast<BinaryOperator>(V)) ||
BO->getOpcode() != Instruction::Mul) {
Factors.push_back(V);
return;
}
+ // 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
+ // uses and we can't factor it.
+ if (!IsRoot) {
+ for (unsigned i = 0, e = Ops.size(); i != e; ++i)
+ if (Ops[i].Op == V) {
+ Factors.push_back(V);
+ return;
+ }
+ }
+
+
// Otherwise, add the LHS and RHS to the list of factors.
- FindSingleUseMultiplyFactors(BO->getOperand(1), Factors);
- FindSingleUseMultiplyFactors(BO->getOperand(0), Factors);
+ FindSingleUseMultiplyFactors(BO->getOperand(1), Factors, Ops, false);
+ FindSingleUseMultiplyFactors(BO->getOperand(0), Factors, Ops, false);
}
/// OptimizeAndOrXor - Optimize a series of operands to an 'and', 'or', or 'xor'
// Compute all of the factors of this added value.
SmallVector<Value*, 8> Factors;
- FindSingleUseMultiplyFactors(BOp, Factors);
+ FindSingleUseMultiplyFactors(BOp, Factors, Ops, true);
assert(Factors.size() > 1 && "Bad linearize!");
// Add one to FactorOccurrences for each unique factor in this op.
Instruction *DummyInst = BinaryOperator::CreateAdd(MaxOccVal, MaxOccVal);
SmallVector<Value*, 4> NewMulOps;
for (unsigned i = 0, e = Ops.size(); i != e; ++i) {
+ // Only try to remove factors from expressions we're allowed to.
+ BinaryOperator *BOp = dyn_cast<BinaryOperator>(Ops[i].Op);
+ if (BOp == 0 || BOp->getOpcode() != Instruction::Mul || !BOp->use_empty())
+ continue;
+
if (Value *V = RemoveFactorFromExpression(Ops[i].Op, MaxOccVal)) {
NewMulOps.push_back(V);
Ops.erase(Ops.begin()+i);
// No need for extra uses anymore.
delete DummyInst;
-
+
unsigned NumAddedValues = NewMulOps.size();
Value *V = EmitAddTreeOfValues(I, NewMulOps);
-
+
// Now that we have inserted the add tree, optimize it. This allows us to
// handle cases that require multiple factoring steps, such as this:
// A*A*B + A*A*C --> A*(A*B+A*C) --> A*(A*(B+C))
assert(NumAddedValues > 1 && "Each occurrence should contribute a value");
+ (void)NumAddedValues;
V = ReassociateExpression(cast<BinaryOperator>(V));
// Create the multiply.
}
// Reject cases where it is pointless to do this.
- if (!isa<BinaryOperator>(BI) || BI->getType()->isFloatingPoint() ||
- isa<VectorType>(BI->getType()))
+ if (!isa<BinaryOperator>(BI) || BI->getType()->isFloatingPointTy() ||
+ BI->getType()->isVectorTy())
continue; // Floating point ops are not associative.
+ // Do not reassociate boolean (i1) expressions. We want to preserve the
+ // original order of evaluation for short-circuited comparisons that
+ // SimplifyCFG has folded to AND/OR expressions. If the expression
+ // is not further optimized, it is likely to be transformed back to a
+ // short-circuited form for code gen, and the source order may have been
+ // optimized for the most likely conditions.
+ if (BI->getType()->isIntegerTy(1))
+ continue;
+
// 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 (ShouldBreakUpSubtract(BI)) {
BI = BreakUpSubtract(BI, ValueRankMap);
+ // Reset the BBI iterator in case BreakUpSubtract changed the
+ // instruction it points to.
+ BBI = BI;
+ ++BBI;
MadeChange = true;
} else if (BinaryOperator::isNeg(BI)) {
// Otherwise, this is a negation. See if the operand is a multiply tree
SmallVector<ValueEntry, 8> Ops;
LinearizeExprTree(I, Ops);
- DEBUG(errs() << "RAIn:\t"; PrintOps(I, Ops); errs() << '\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
// the operands and their ranks, sort the operands by their rank. Use a
if (Value *V = OptimizeExpression(I, Ops)) {
// This expression tree simplified to something that isn't a tree,
// eliminate it.
- DEBUG(errs() << "Reassoc to scalar: " << *V << '\n');
+ DEBUG(dbgs() << "Reassoc to scalar: " << *V << '\n');
I->replaceAllUsesWith(V);
RemoveDeadBinaryOp(I);
++NumAnnihil;
Ops.insert(Ops.begin(), Tmp);
}
- DEBUG(errs() << "RAOut:\t"; PrintOps(I, Ops); errs() << '\n');
+ DEBUG(dbgs() << "RAOut:\t"; PrintOps(I, Ops); dbgs() << '\n');
if (Ops.size() == 1) {
// This expression tree simplified to something that isn't a tree,
projects / oota-llvm.git / blobdiff