#include "InstCombine.h"
#include "llvm/Analysis/InstructionSimplify.h"
#include "llvm/IR/IntrinsicInst.h"
-#include "llvm/Support/PatternMatch.h"
+#include "llvm/IR/PatternMatch.h"
using namespace llvm;
using namespace PatternMatch;
+#define DEBUG_TYPE "instcombine"
+
/// simplifyValueKnownNonZero - The specific integer value is used in a context
/// where it is known to be non-zero. If this allows us to simplify the
bool Changed = SimplifyAssociativeOrCommutative(I);
Value *Op0 = I.getOperand(0), *Op1 = I.getOperand(1);
- if (Value *V = SimplifyMulInst(Op0, Op1, TD))
+ if (Value *V = SimplifyMulInst(Op0, Op1, DL))
return ReplaceInstUsesWith(I, V);
if (Value *V = SimplifyUsingDistributiveLaws(I))
}
if (ConstantInt *CI = dyn_cast<ConstantInt>(Op1)) {
- // Canonicalize (X+C1)*CI -> X*CI+C1*CI.
- { Value *X; ConstantInt *C1;
- if (Op0->hasOneUse() &&
- match(Op0, m_Add(m_Value(X), m_ConstantInt(C1)))) {
- Value *Add = Builder->CreateMul(X, CI);
- return BinaryOperator::CreateAdd(Add, Builder->CreateMul(C1, CI));
- }
- }
-
// (Y - X) * (-(2**n)) -> (X - Y) * (2**n), for positive nonzero n
// (Y + const) * (-(2**n)) -> (-constY) * (2**n), for positive nonzero n
// The "* (2**n)" thus becomes a potential shifting opportunity.
if (isa<PHINode>(Op0))
if (Instruction *NV = FoldOpIntoPhi(I))
return NV;
+
+ // Canonicalize (X+C1)*CI -> X*CI+C1*CI.
+ {
+ Value *X;
+ Constant *C1;
+ if (match(Op0, m_OneUse(m_Add(m_Value(X), m_Constant(C1))))) {
+ Value *Add = Builder->CreateMul(X, Op1);
+ return BinaryOperator::CreateAdd(Add, Builder->CreateMul(C1, Op1));
+ }
+ }
}
if (Value *Op0v = dyn_castNegVal(Op0)) // -X * -Y = X*Y
}
/// i1 mul -> i1 and.
- if (I.getType()->isIntegerTy(1))
+ if (I.getType()->getScalarType()->isIntegerTy(1))
return BinaryOperator::CreateAnd(Op0, Op1);
// X*(1 << Y) --> X << Y
if (I->getOpcode() != Instruction::FMul || !I->hasUnsafeAlgebra())
return;
- ConstantFP *CFP = dyn_cast<ConstantFP>(I->getOperand(0));
- if (CFP && CFP->isExactlyValue(0.5)) {
+ if (match(I->getOperand(0), m_SpecificFP(0.5)))
Y = I->getOperand(1);
- return;
- }
- CFP = dyn_cast<ConstantFP>(I->getOperand(1));
- if (CFP && CFP->isExactlyValue(0.5))
+ else if (match(I->getOperand(1), m_SpecificFP(0.5)))
Y = I->getOperand(0);
}
+static bool isFiniteNonZeroFp(Constant *C) {
+ if (C->getType()->isVectorTy()) {
+ for (unsigned I = 0, E = C->getType()->getVectorNumElements(); I != E;
+ ++I) {
+ ConstantFP *CFP = dyn_cast<ConstantFP>(C->getAggregateElement(I));
+ if (!CFP || !CFP->getValueAPF().isFiniteNonZero())
+ return false;
+ }
+ return true;
+ }
+
+ return isa<ConstantFP>(C) &&
+ cast<ConstantFP>(C)->getValueAPF().isFiniteNonZero();
+}
+
+static bool isNormalFp(Constant *C) {
+ if (C->getType()->isVectorTy()) {
+ for (unsigned I = 0, E = C->getType()->getVectorNumElements(); I != E;
+ ++I) {
+ ConstantFP *CFP = dyn_cast<ConstantFP>(C->getAggregateElement(I));
+ if (!CFP || !CFP->getValueAPF().isNormal())
+ return false;
+ }
+ return true;
+ }
+
+ return isa<ConstantFP>(C) && cast<ConstantFP>(C)->getValueAPF().isNormal();
+}
+
/// Helper function of InstCombiner::visitFMul(BinaryOperator(). It returns
/// true iff the given value is FMul or FDiv with one and only one operand
/// being a normal constant (i.e. not Zero/NaN/Infinity).
I->getOpcode() != Instruction::FDiv))
return false;
- ConstantFP *C0 = dyn_cast<ConstantFP>(I->getOperand(0));
- ConstantFP *C1 = dyn_cast<ConstantFP>(I->getOperand(1));
+ Constant *C0 = dyn_cast<Constant>(I->getOperand(0));
+ Constant *C1 = dyn_cast<Constant>(I->getOperand(1));
if (C0 && C1)
return false;
- return (C0 && C0->getValueAPF().isFiniteNonZero()) ||
- (C1 && C1->getValueAPF().isFiniteNonZero());
-}
-
-static bool isNormalFp(const ConstantFP *C) {
- const APFloat &Flt = C->getValueAPF();
- return Flt.isNormal();
+ return (C0 && isFiniteNonZeroFp(C0)) || (C1 && isFiniteNonZeroFp(C1));
}
/// foldFMulConst() is a helper routine of InstCombiner::visitFMul().
/// resulting expression. Note that this function could return NULL in
/// case the constants cannot be folded into a normal floating-point.
///
-Value *InstCombiner::foldFMulConst(Instruction *FMulOrDiv, ConstantFP *C,
+Value *InstCombiner::foldFMulConst(Instruction *FMulOrDiv, Constant *C,
Instruction *InsertBefore) {
assert(isFMulOrFDivWithConstant(FMulOrDiv) && "V is invalid");
Value *Opnd0 = FMulOrDiv->getOperand(0);
Value *Opnd1 = FMulOrDiv->getOperand(1);
- ConstantFP *C0 = dyn_cast<ConstantFP>(Opnd0);
- ConstantFP *C1 = dyn_cast<ConstantFP>(Opnd1);
+ Constant *C0 = dyn_cast<Constant>(Opnd0);
+ Constant *C1 = dyn_cast<Constant>(Opnd1);
BinaryOperator *R = 0;
// (X * C0) * C => X * (C0*C)
if (FMulOrDiv->getOpcode() == Instruction::FMul) {
Constant *F = ConstantExpr::getFMul(C1 ? C1 : C0, C);
- if (isNormalFp(cast<ConstantFP>(F)))
+ if (isNormalFp(F))
R = BinaryOperator::CreateFMul(C1 ? Opnd0 : Opnd1, F);
} else {
if (C0) {
// (C0 / X) * C => (C0 * C) / X
- ConstantFP *F = cast<ConstantFP>(ConstantExpr::getFMul(C0, C));
- if (isNormalFp(F))
- R = BinaryOperator::CreateFDiv(F, Opnd1);
+ if (FMulOrDiv->hasOneUse()) {
+ // It would otherwise introduce another div.
+ Constant *F = ConstantExpr::getFMul(C0, C);
+ if (isNormalFp(F))
+ R = BinaryOperator::CreateFDiv(F, Opnd1);
+ }
} else {
// (X / C1) * C => X * (C/C1) if C/C1 is not a denormal
- ConstantFP *F = cast<ConstantFP>(ConstantExpr::getFDiv(C, C1));
+ Constant *F = ConstantExpr::getFDiv(C, C1);
if (isNormalFp(F)) {
R = BinaryOperator::CreateFMul(Opnd0, F);
} else {
// (X / C1) * C => X / (C1/C)
Constant *F = ConstantExpr::getFDiv(C1, C);
- if (isNormalFp(cast<ConstantFP>(F)))
+ if (isNormalFp(F))
R = BinaryOperator::CreateFDiv(Opnd0, F);
}
}
if (isa<Constant>(Op0))
std::swap(Op0, Op1);
- if (Value *V = SimplifyFMulInst(Op0, Op1, I.getFastMathFlags(), TD))
+ if (Value *V = SimplifyFMulInst(Op0, Op1, I.getFastMathFlags(), DL))
return ReplaceInstUsesWith(I, V);
bool AllowReassociate = I.hasUnsafeAlgebra();
if (Instruction *NV = FoldOpIntoPhi(I))
return NV;
- ConstantFP *C = dyn_cast<ConstantFP>(Op1);
- if (C && AllowReassociate && C->getValueAPF().isFiniteNonZero()) {
+ // (fmul X, -1.0) --> (fsub -0.0, X)
+ if (match(Op1, m_SpecificFP(-1.0))) {
+ Constant *NegZero = ConstantFP::getNegativeZero(Op1->getType());
+ Instruction *RI = BinaryOperator::CreateFSub(NegZero, Op0);
+ RI->copyFastMathFlags(&I);
+ return RI;
+ }
+
+ Constant *C = cast<Constant>(Op1);
+ if (AllowReassociate && isFiniteNonZeroFp(C)) {
// Let MDC denote an expression in one of these forms:
// X * C, C/X, X/C, where C is a constant.
//
// Try to simplify "MDC * Constant"
- if (isFMulOrFDivWithConstant(Op0)) {
- Value *V = foldFMulConst(cast<Instruction>(Op0), C, &I);
- if (V)
+ if (isFMulOrFDivWithConstant(Op0))
+ if (Value *V = foldFMulConst(cast<Instruction>(Op0), C, &I))
return ReplaceInstUsesWith(I, V);
- }
// (MDC +/- C1) * C => (MDC * C) +/- (C1 * C)
Instruction *FAddSub = dyn_cast<Instruction>(Op0);
FAddSub->getOpcode() == Instruction::FSub)) {
Value *Opnd0 = FAddSub->getOperand(0);
Value *Opnd1 = FAddSub->getOperand(1);
- ConstantFP *C0 = dyn_cast<ConstantFP>(Opnd0);
- ConstantFP *C1 = dyn_cast<ConstantFP>(Opnd1);
+ Constant *C0 = dyn_cast<Constant>(Opnd0);
+ Constant *C1 = dyn_cast<Constant>(Opnd1);
bool Swap = false;
if (C0) {
std::swap(C0, C1);
Swap = true;
}
- if (C1 && C1->getValueAPF().isFiniteNonZero() &&
- isFMulOrFDivWithConstant(Opnd0)) {
+ if (C1 && isFiniteNonZeroFp(C1) && isFMulOrFDivWithConstant(Opnd0)) {
Value *M1 = ConstantExpr::getFMul(C1, C);
- Value *M0 = isNormalFp(cast<ConstantFP>(M1)) ?
+ Value *M0 = isNormalFp(cast<Constant>(M1)) ?
foldFMulConst(cast<Instruction>(Opnd0), C, &I) :
0;
if (M0 && M1) {
if (Swap && FAddSub->getOpcode() == Instruction::FSub)
std::swap(M0, M1);
- Value *R = (FAddSub->getOpcode() == Instruction::FAdd) ?
- BinaryOperator::CreateFAdd(M0, M1) :
- BinaryOperator::CreateFSub(M0, M1);
- Instruction *RI = cast<Instruction>(R);
+ Instruction *RI = (FAddSub->getOpcode() == Instruction::FAdd)
+ ? BinaryOperator::CreateFAdd(M0, M1)
+ : BinaryOperator::CreateFSub(M0, M1);
RI->copyFastMathFlags(&I);
return RI;
}
}
// if pattern detected emit alternate sequence
if (OpX && OpY) {
+ BuilderTy::FastMathFlagGuard Guard(*Builder);
+ Builder->SetFastMathFlags(Log2->getFastMathFlags());
Log2->setArgOperand(0, OpY);
Value *FMulVal = Builder->CreateFMul(OpX, Log2);
- Instruction *FMul = cast<Instruction>(FMulVal);
- FMul->copyFastMathFlags(Log2);
- Instruction *FSub = BinaryOperator::CreateFSub(FMulVal, OpX);
- FSub->copyFastMathFlags(Log2);
- return FSub;
+ Value *FSub = Builder->CreateFSub(FMulVal, OpX);
+ FSub->takeName(&I);
+ return ReplaceInstUsesWith(I, FSub);
}
}
for (int i = 0; i < 2; i++) {
bool IgnoreZeroSign = I.hasNoSignedZeros();
if (BinaryOperator::isFNeg(Opnd0, IgnoreZeroSign)) {
+ BuilderTy::FastMathFlagGuard Guard(*Builder);
+ Builder->SetFastMathFlags(I.getFastMathFlags());
+
Value *N0 = dyn_castFNegVal(Opnd0, IgnoreZeroSign);
Value *N1 = dyn_castFNegVal(Opnd1, IgnoreZeroSign);
// -X * -Y => X*Y
- if (N1)
- return BinaryOperator::CreateFMul(N0, N1);
+ if (N1) {
+ Value *FMul = Builder->CreateFMul(N0, N1);
+ FMul->takeName(&I);
+ return ReplaceInstUsesWith(I, FMul);
+ }
if (Opnd0->hasOneUse()) {
// -X * Y => -(X*Y) (Promote negation as high as possible)
Value *T = Builder->CreateFMul(N0, Opnd1);
- cast<Instruction>(T)->setDebugLoc(I.getDebugLoc());
- Instruction *Neg = BinaryOperator::CreateFNeg(T);
- if (I.getFastMathFlags().any()) {
- cast<Instruction>(T)->copyFastMathFlags(&I);
- Neg->copyFastMathFlags(&I);
- }
- return Neg;
+ Value *Neg = Builder->CreateFNeg(T);
+ Neg->takeName(&I);
+ return ReplaceInstUsesWith(I, Neg);
}
}
Y = Opnd0_0;
if (Y) {
- Instruction *T = cast<Instruction>(Builder->CreateFMul(Opnd1, Opnd1));
- T->copyFastMathFlags(&I);
- T->setDebugLoc(I.getDebugLoc());
+ BuilderTy::FastMathFlagGuard Guard(*Builder);
+ Builder->SetFastMathFlags(I.getFastMathFlags());
+ Value *T = Builder->CreateFMul(Opnd1, Opnd1);
- Instruction *R = BinaryOperator::CreateFMul(T, Y);
- R->copyFastMathFlags(&I);
- return R;
+ Value *R = Builder->CreateFMul(T, Y);
+ R->takeName(&I);
+ return ReplaceInstUsesWith(I, R);
}
}
}
+ // B * (uitofp i1 C) -> select C, B, 0
+ if (I.hasNoNaNs() && I.hasNoInfs() && I.hasNoSignedZeros()) {
+ Value *LHS = Op0, *RHS = Op1;
+ Value *B, *C;
+ if (!match(RHS, m_UIToFP(m_Value(C))))
+ std::swap(LHS, RHS);
+
+ if (match(RHS, m_UIToFP(m_Value(C))) &&
+ C->getType()->getScalarType()->isIntegerTy(1)) {
+ B = LHS;
+ Value *Zero = ConstantFP::getNegativeZero(B->getType());
+ return SelectInst::Create(C, B, Zero);
+ }
+ }
+
+ // A * (1 - uitofp i1 C) -> select C, 0, A
+ if (I.hasNoNaNs() && I.hasNoInfs() && I.hasNoSignedZeros()) {
+ Value *LHS = Op0, *RHS = Op1;
+ Value *A, *C;
+ if (!match(RHS, m_FSub(m_FPOne(), m_UIToFP(m_Value(C)))))
+ std::swap(LHS, RHS);
+
+ if (match(RHS, m_FSub(m_FPOne(), m_UIToFP(m_Value(C)))) &&
+ C->getType()->getScalarType()->isIntegerTy(1)) {
+ A = LHS;
+ Value *Zero = ConstantFP::getNegativeZero(A->getType());
+ return SelectInst::Create(C, Zero, A);
+ }
+ }
+
if (!isa<Constant>(Op1))
std::swap(Opnd0, Opnd1);
else
return 0;
}
-Instruction *InstCombiner::visitUDiv(BinaryOperator &I) {
- Value *Op0 = I.getOperand(0), *Op1 = I.getOperand(1);
+namespace {
+const unsigned MaxDepth = 6;
+typedef Instruction *(*FoldUDivOperandCb)(Value *Op0, Value *Op1,
+ const BinaryOperator &I,
+ InstCombiner &IC);
+
+/// \brief Used to maintain state for visitUDivOperand().
+struct UDivFoldAction {
+ FoldUDivOperandCb FoldAction; ///< Informs visitUDiv() how to fold this
+ ///< operand. This can be zero if this action
+ ///< joins two actions together.
+
+ Value *OperandToFold; ///< Which operand to fold.
+ union {
+ Instruction *FoldResult; ///< The instruction returned when FoldAction is
+ ///< invoked.
+
+ size_t SelectLHSIdx; ///< Stores the LHS action index if this action
+ ///< joins two actions together.
+ };
+
+ UDivFoldAction(FoldUDivOperandCb FA, Value *InputOperand)
+ : FoldAction(FA), OperandToFold(InputOperand), FoldResult(0) {}
+ UDivFoldAction(FoldUDivOperandCb FA, Value *InputOperand, size_t SLHS)
+ : FoldAction(FA), OperandToFold(InputOperand), SelectLHSIdx(SLHS) {}
+};
+}
- if (Value *V = SimplifyUDivInst(Op0, Op1, TD))
- return ReplaceInstUsesWith(I, V);
+// X udiv 2^C -> X >> C
+static Instruction *foldUDivPow2Cst(Value *Op0, Value *Op1,
+ const BinaryOperator &I, InstCombiner &IC) {
+ const APInt &C = cast<Constant>(Op1)->getUniqueInteger();
+ BinaryOperator *LShr = BinaryOperator::CreateLShr(
+ Op0, ConstantInt::get(Op0->getType(), C.logBase2()));
+ if (I.isExact()) LShr->setIsExact();
+ return LShr;
+}
- // Handle the integer div common cases
- if (Instruction *Common = commonIDivTransforms(I))
- return Common;
+// X udiv C, where C >= signbit
+static Instruction *foldUDivNegCst(Value *Op0, Value *Op1,
+ const BinaryOperator &I, InstCombiner &IC) {
+ Value *ICI = IC.Builder->CreateICmpULT(Op0, cast<ConstantInt>(Op1));
- {
- // X udiv 2^C -> X >> C
- // Check to see if this is an unsigned division with an exact power of 2,
- // if so, convert to a right shift.
- const APInt *C;
- if (match(Op1, m_Power2(C))) {
- BinaryOperator *LShr =
- BinaryOperator::CreateLShr(Op0,
- ConstantInt::get(Op0->getType(),
- C->logBase2()));
- if (I.isExact()) LShr->setIsExact();
- return LShr;
- }
+ return SelectInst::Create(ICI, Constant::getNullValue(I.getType()),
+ ConstantInt::get(I.getType(), 1));
+}
+
+// X udiv (C1 << N), where C1 is "1<<C2" --> X >> (N+C2)
+static Instruction *foldUDivShl(Value *Op0, Value *Op1, const BinaryOperator &I,
+ InstCombiner &IC) {
+ Instruction *ShiftLeft = cast<Instruction>(Op1);
+ if (isa<ZExtInst>(ShiftLeft))
+ ShiftLeft = cast<Instruction>(ShiftLeft->getOperand(0));
+
+ const APInt &CI =
+ cast<Constant>(ShiftLeft->getOperand(0))->getUniqueInteger();
+ Value *N = ShiftLeft->getOperand(1);
+ if (CI != 1)
+ N = IC.Builder->CreateAdd(N, ConstantInt::get(N->getType(), CI.logBase2()));
+ if (ZExtInst *Z = dyn_cast<ZExtInst>(Op1))
+ N = IC.Builder->CreateZExt(N, Z->getDestTy());
+ BinaryOperator *LShr = BinaryOperator::CreateLShr(Op0, N);
+ if (I.isExact()) LShr->setIsExact();
+ return LShr;
+}
+
+// \brief Recursively visits the possible right hand operands of a udiv
+// instruction, seeing through select instructions, to determine if we can
+// replace the udiv with something simpler. If we find that an operand is not
+// able to simplify the udiv, we abort the entire transformation.
+static size_t visitUDivOperand(Value *Op0, Value *Op1, const BinaryOperator &I,
+ SmallVectorImpl<UDivFoldAction> &Actions,
+ unsigned Depth = 0) {
+ // Check to see if this is an unsigned division with an exact power of 2,
+ // if so, convert to a right shift.
+ if (match(Op1, m_Power2())) {
+ Actions.push_back(UDivFoldAction(foldUDivPow2Cst, Op1));
+ return Actions.size();
}
- if (ConstantInt *C = dyn_cast<ConstantInt>(Op1)) {
+ if (ConstantInt *C = dyn_cast<ConstantInt>(Op1))
// X udiv C, where C >= signbit
if (C->getValue().isNegative()) {
- Value *IC = Builder->CreateICmpULT(Op0, C);
- return SelectInst::Create(IC, Constant::getNullValue(I.getType()),
- ConstantInt::get(I.getType(), 1));
+ Actions.push_back(UDivFoldAction(foldUDivNegCst, C));
+ return Actions.size();
}
- }
-
- // (x lshr C1) udiv C2 --> x udiv (C2 << C1)
- if (ConstantInt *C2 = dyn_cast<ConstantInt>(Op1)) {
- Value *X;
- ConstantInt *C1;
- if (match(Op0, m_LShr(m_Value(X), m_ConstantInt(C1)))) {
- APInt NC = C2->getValue().shl(C1->getLimitedValue(C1->getBitWidth()-1));
- return BinaryOperator::CreateUDiv(X, Builder->getInt(NC));
- }
- }
// X udiv (C1 << N), where C1 is "1<<C2" --> X >> (N+C2)
- { const APInt *CI; Value *N;
- if (match(Op1, m_Shl(m_Power2(CI), m_Value(N))) ||
- match(Op1, m_ZExt(m_Shl(m_Power2(CI), m_Value(N))))) {
- if (*CI != 1)
- N = Builder->CreateAdd(N,
- ConstantInt::get(N->getType(), CI->logBase2()));
- if (ZExtInst *Z = dyn_cast<ZExtInst>(Op1))
- N = Builder->CreateZExt(N, Z->getDestTy());
- if (I.isExact())
- return BinaryOperator::CreateExactLShr(Op0, N);
- return BinaryOperator::CreateLShr(Op0, N);
- }
+ if (match(Op1, m_Shl(m_Power2(), m_Value())) ||
+ match(Op1, m_ZExt(m_Shl(m_Power2(), m_Value())))) {
+ Actions.push_back(UDivFoldAction(foldUDivShl, Op1));
+ return Actions.size();
}
- // udiv X, (Select Cond, C1, C2) --> Select Cond, (shr X, C1), (shr X, C2)
- // where C1&C2 are powers of two.
- { Value *Cond; const APInt *C1, *C2;
- if (match(Op1, m_Select(m_Value(Cond), m_Power2(C1), m_Power2(C2)))) {
- // Construct the "on true" case of the select
- Value *TSI = Builder->CreateLShr(Op0, C1->logBase2(), Op1->getName()+".t",
- I.isExact());
+ // The remaining tests are all recursive, so bail out if we hit the limit.
+ if (Depth++ == MaxDepth)
+ return 0;
- // Construct the "on false" case of the select
- Value *FSI = Builder->CreateLShr(Op0, C2->logBase2(), Op1->getName()+".f",
- I.isExact());
+ if (SelectInst *SI = dyn_cast<SelectInst>(Op1))
+ if (size_t LHSIdx = visitUDivOperand(Op0, SI->getOperand(1), I, Actions))
+ if (visitUDivOperand(Op0, SI->getOperand(2), I, Actions)) {
+ Actions.push_back(UDivFoldAction((FoldUDivOperandCb)0, Op1, LHSIdx-1));
+ return Actions.size();
+ }
- // construct the select instruction and return it.
- return SelectInst::Create(Cond, TSI, FSI);
- }
+ return 0;
+}
+
+Instruction *InstCombiner::visitUDiv(BinaryOperator &I) {
+ Value *Op0 = I.getOperand(0), *Op1 = I.getOperand(1);
+
+ if (Value *V = SimplifyUDivInst(Op0, Op1, DL))
+ return ReplaceInstUsesWith(I, V);
+
+ // Handle the integer div common cases
+ if (Instruction *Common = commonIDivTransforms(I))
+ return Common;
+
+ // (x lshr C1) udiv C2 --> x udiv (C2 << C1)
+ if (Constant *C2 = dyn_cast<Constant>(Op1)) {
+ Value *X;
+ Constant *C1;
+ if (match(Op0, m_LShr(m_Value(X), m_Constant(C1))))
+ return BinaryOperator::CreateUDiv(X, ConstantExpr::getShl(C2, C1));
}
// (zext A) udiv (zext B) --> zext (A udiv B)
I.isExact()),
I.getType());
+ // (LHS udiv (select (select (...)))) -> (LHS >> (select (select (...))))
+ SmallVector<UDivFoldAction, 6> UDivActions;
+ if (visitUDivOperand(Op0, Op1, I, UDivActions))
+ for (unsigned i = 0, e = UDivActions.size(); i != e; ++i) {
+ FoldUDivOperandCb Action = UDivActions[i].FoldAction;
+ Value *ActionOp1 = UDivActions[i].OperandToFold;
+ Instruction *Inst;
+ if (Action)
+ Inst = Action(Op0, ActionOp1, I, *this);
+ else {
+ // This action joins two actions together. The RHS of this action is
+ // simply the last action we processed, we saved the LHS action index in
+ // the joining action.
+ size_t SelectRHSIdx = i - 1;
+ Value *SelectRHS = UDivActions[SelectRHSIdx].FoldResult;
+ size_t SelectLHSIdx = UDivActions[i].SelectLHSIdx;
+ Value *SelectLHS = UDivActions[SelectLHSIdx].FoldResult;
+ Inst = SelectInst::Create(cast<SelectInst>(ActionOp1)->getCondition(),
+ SelectLHS, SelectRHS);
+ }
+
+ // If this is the last action to process, return it to the InstCombiner.
+ // Otherwise, we insert it before the UDiv and record it so that we may
+ // use it as part of a joining action (i.e., a SelectInst).
+ if (e - i != 1) {
+ Inst->insertBefore(&I);
+ UDivActions[i].FoldResult = Inst;
+ } else
+ return Inst;
+ }
+
return 0;
}
Instruction *InstCombiner::visitSDiv(BinaryOperator &I) {
Value *Op0 = I.getOperand(0), *Op1 = I.getOperand(1);
- if (Value *V = SimplifySDivInst(Op0, Op1, TD))
+ if (Value *V = SimplifySDivInst(Op0, Op1, DL))
return ReplaceInstUsesWith(I, V);
// Handle the integer div common cases
if (Instruction *Common = commonIDivTransforms(I))
return Common;
- if (ConstantInt *RHS = dyn_cast<ConstantInt>(Op1)) {
- // sdiv X, -1 == -X
- if (RHS->isAllOnesValue())
- return BinaryOperator::CreateNeg(Op0);
+ // sdiv X, -1 == -X
+ if (match(Op1, m_AllOnes()))
+ return BinaryOperator::CreateNeg(Op0);
+ if (ConstantInt *RHS = dyn_cast<ConstantInt>(Op1)) {
// sdiv X, C --> ashr exact X, log2(C)
if (I.isExact() && RHS->getValue().isNonNegative() &&
RHS->getValue().isPowerOf2()) {
RHS->getValue().exactLogBase2());
return BinaryOperator::CreateExactAShr(Op0, ShAmt, I.getName());
}
+ }
+ if (Constant *RHS = dyn_cast<Constant>(Op1)) {
// -X/C --> X/-C provided the negation doesn't overflow.
if (SubOperator *Sub = dyn_cast<SubOperator>(Op0))
if (match(Sub->getOperand(0), m_Zero()) && Sub->hasNoSignedWrap())
/// returned; otherwise, NULL is returned.
///
static Instruction *CvtFDivConstToReciprocal(Value *Dividend,
- ConstantFP *Divisor,
+ Constant *Divisor,
bool AllowReciprocal) {
- const APFloat &FpVal = Divisor->getValueAPF();
+ if (!isa<ConstantFP>(Divisor)) // TODO: handle vectors.
+ return 0;
+
+ const APFloat &FpVal = cast<ConstantFP>(Divisor)->getValueAPF();
APFloat Reciprocal(FpVal.getSemantics());
bool Cvt = FpVal.getExactInverse(&Reciprocal);
Instruction *InstCombiner::visitFDiv(BinaryOperator &I) {
Value *Op0 = I.getOperand(0), *Op1 = I.getOperand(1);
- if (Value *V = SimplifyFDivInst(Op0, Op1, TD))
+ if (Value *V = SimplifyFDivInst(Op0, Op1, DL))
return ReplaceInstUsesWith(I, V);
+ if (isa<Constant>(Op0))
+ if (SelectInst *SI = dyn_cast<SelectInst>(Op1))
+ if (Instruction *R = FoldOpIntoSelect(I, SI))
+ return R;
+
bool AllowReassociate = I.hasUnsafeAlgebra();
bool AllowReciprocal = I.hasAllowReciprocal();
- if (ConstantFP *Op1C = dyn_cast<ConstantFP>(Op1)) {
+ if (Constant *Op1C = dyn_cast<Constant>(Op1)) {
+ if (SelectInst *SI = dyn_cast<SelectInst>(Op0))
+ if (Instruction *R = FoldOpIntoSelect(I, SI))
+ return R;
+
if (AllowReassociate) {
- ConstantFP *C1 = 0;
- ConstantFP *C2 = Op1C;
+ Constant *C1 = 0;
+ Constant *C2 = Op1C;
Value *X;
Instruction *Res = 0;
- if (match(Op0, m_FMul(m_Value(X), m_ConstantFP(C1)))) {
+ if (match(Op0, m_FMul(m_Value(X), m_Constant(C1)))) {
// (X*C1)/C2 => X * (C1/C2)
//
Constant *C = ConstantExpr::getFDiv(C1, C2);
- const APFloat &F = cast<ConstantFP>(C)->getValueAPF();
- if (F.isNormal())
+ if (isNormalFp(C))
Res = BinaryOperator::CreateFMul(X, C);
- } else if (match(Op0, m_FDiv(m_Value(X), m_ConstantFP(C1)))) {
+ } else if (match(Op0, m_FDiv(m_Value(X), m_Constant(C1)))) {
// (X/C1)/C2 => X /(C2*C1) [=> X * 1/(C2*C1) if reciprocal is allowed]
//
Constant *C = ConstantExpr::getFMul(C1, C2);
- const APFloat &F = cast<ConstantFP>(C)->getValueAPF();
- if (F.isNormal()) {
- Res = CvtFDivConstToReciprocal(X, cast<ConstantFP>(C),
- AllowReciprocal);
+ if (isNormalFp(C)) {
+ Res = CvtFDivConstToReciprocal(X, C, AllowReciprocal);
if (!Res)
Res = BinaryOperator::CreateFDiv(X, C);
}
}
// X / C => X * 1/C
- if (Instruction *T = CvtFDivConstToReciprocal(Op0, Op1C, AllowReciprocal))
+ if (Instruction *T = CvtFDivConstToReciprocal(Op0, Op1C, AllowReciprocal)) {
+ T->copyFastMathFlags(&I);
return T;
+ }
return 0;
}
- if (AllowReassociate && isa<ConstantFP>(Op0)) {
- ConstantFP *C1 = cast<ConstantFP>(Op0), *C2;
+ if (AllowReassociate && isa<Constant>(Op0)) {
+ Constant *C1 = cast<Constant>(Op0), *C2;
Constant *Fold = 0;
Value *X;
bool CreateDiv = true;
// C1 / (X*C2) => (C1/C2) / X
- if (match(Op1, m_FMul(m_Value(X), m_ConstantFP(C2))))
+ if (match(Op1, m_FMul(m_Value(X), m_Constant(C2))))
Fold = ConstantExpr::getFDiv(C1, C2);
- else if (match(Op1, m_FDiv(m_Value(X), m_ConstantFP(C2)))) {
+ else if (match(Op1, m_FDiv(m_Value(X), m_Constant(C2)))) {
// C1 / (X/C2) => (C1*C2) / X
Fold = ConstantExpr::getFMul(C1, C2);
- } else if (match(Op1, m_FDiv(m_ConstantFP(C2), m_Value(X)))) {
+ } else if (match(Op1, m_FDiv(m_Constant(C2), m_Value(X)))) {
// C1 / (C2/X) => (C1/C2) * X
Fold = ConstantExpr::getFDiv(C1, C2);
CreateDiv = false;
}
- if (Fold) {
- const APFloat &FoldC = cast<ConstantFP>(Fold)->getValueAPF();
- if (FoldC.isNormal()) {
- Instruction *R = CreateDiv ?
- BinaryOperator::CreateFDiv(Fold, X) :
- BinaryOperator::CreateFMul(X, Fold);
- R->setFastMathFlags(I.getFastMathFlags());
- return R;
- }
+ if (Fold && isNormalFp(Fold)) {
+ Instruction *R = CreateDiv ? BinaryOperator::CreateFDiv(Fold, X)
+ : BinaryOperator::CreateFMul(X, Fold);
+ R->setFastMathFlags(I.getFastMathFlags());
+ return R;
}
return 0;
}
if (Op0->hasOneUse() && match(Op0, m_FDiv(m_Value(X), m_Value(Y)))) {
// (X/Y) / Z => X / (Y*Z)
//
- if (!isa<ConstantFP>(Y) || !isa<ConstantFP>(Op1)) {
+ if (!isa<Constant>(Y) || !isa<Constant>(Op1)) {
NewInst = Builder->CreateFMul(Y, Op1);
+ if (Instruction *RI = dyn_cast<Instruction>(NewInst)) {
+ FastMathFlags Flags = I.getFastMathFlags();
+ Flags &= cast<Instruction>(Op0)->getFastMathFlags();
+ RI->setFastMathFlags(Flags);
+ }
SimpR = BinaryOperator::CreateFDiv(X, NewInst);
}
} else if (Op1->hasOneUse() && match(Op1, m_FDiv(m_Value(X), m_Value(Y)))) {
// Z / (X/Y) => Z*Y / X
//
- if (!isa<ConstantFP>(Y) || !isa<ConstantFP>(Op0)) {
+ if (!isa<Constant>(Y) || !isa<Constant>(Op0)) {
NewInst = Builder->CreateFMul(Op0, Y);
+ if (Instruction *RI = dyn_cast<Instruction>(NewInst)) {
+ FastMathFlags Flags = I.getFastMathFlags();
+ Flags &= cast<Instruction>(Op1)->getFastMathFlags();
+ RI->setFastMathFlags(Flags);
+ }
SimpR = BinaryOperator::CreateFDiv(NewInst, X);
}
}
if (isa<SelectInst>(Op1) && SimplifyDivRemOfSelect(I))
return &I;
- if (isa<ConstantInt>(Op1)) {
+ if (isa<Constant>(Op1)) {
if (Instruction *Op0I = dyn_cast<Instruction>(Op0)) {
if (SelectInst *SI = dyn_cast<SelectInst>(Op0I)) {
if (Instruction *R = FoldOpIntoSelect(I, SI))
Instruction *InstCombiner::visitURem(BinaryOperator &I) {
Value *Op0 = I.getOperand(0), *Op1 = I.getOperand(1);
- if (Value *V = SimplifyURemInst(Op0, Op1, TD))
+ if (Value *V = SimplifyURemInst(Op0, Op1, DL))
return ReplaceInstUsesWith(I, V);
if (Instruction *common = commonIRemTransforms(I))
return BinaryOperator::CreateAnd(Op0, Add);
}
+ // 1 urem X -> zext(X != 1)
+ if (match(Op0, m_One())) {
+ Value *Cmp = Builder->CreateICmpNE(Op1, Op0);
+ Value *Ext = Builder->CreateZExt(Cmp, I.getType());
+ return ReplaceInstUsesWith(I, Ext);
+ }
+
return 0;
}
Instruction *InstCombiner::visitSRem(BinaryOperator &I) {
Value *Op0 = I.getOperand(0), *Op1 = I.getOperand(1);
- if (Value *V = SimplifySRemInst(Op0, Op1, TD))
+ if (Value *V = SimplifySRemInst(Op0, Op1, DL))
return ReplaceInstUsesWith(I, V);
// Handle the integer rem common cases
Instruction *InstCombiner::visitFRem(BinaryOperator &I) {
Value *Op0 = I.getOperand(0), *Op1 = I.getOperand(1);
- if (Value *V = SimplifyFRemInst(Op0, Op1, TD))
+ if (Value *V = SimplifyFRemInst(Op0, Op1, DL))
return ReplaceInstUsesWith(I, V);
// Handle cases involving: rem X, (select Cond, Y, Z)