static SelectPatternFlavor
MatchSelectPattern(Value *V, Value *&LHS, Value *&RHS) {
SelectInst *SI = dyn_cast<SelectInst>(V);
- if (SI == 0) return SPF_UNKNOWN;
+ if (!SI) return SPF_UNKNOWN;
ICmpInst *ICI = dyn_cast<ICmpInst>(SI->getCondition());
- if (ICI == 0) return SPF_UNKNOWN;
+ if (!ICI) return SPF_UNKNOWN;
- LHS = ICI->getOperand(0);
- RHS = ICI->getOperand(1);
+ ICmpInst::Predicate Pred = ICI->getPredicate();
+ Value *CmpLHS = ICI->getOperand(0);
+ Value *CmpRHS = ICI->getOperand(1);
+ Value *TrueVal = SI->getTrueValue();
+ Value *FalseVal = SI->getFalseValue();
+
+ LHS = CmpLHS;
+ RHS = CmpRHS;
// (icmp X, Y) ? X : Y
- if (SI->getTrueValue() == ICI->getOperand(0) &&
- SI->getFalseValue() == ICI->getOperand(1)) {
- switch (ICI->getPredicate()) {
+ if (TrueVal == CmpLHS && FalseVal == CmpRHS) {
+ switch (Pred) {
default: return SPF_UNKNOWN; // Equality.
case ICmpInst::ICMP_UGT:
case ICmpInst::ICMP_UGE: return SPF_UMAX;
}
// (icmp X, Y) ? Y : X
- if (SI->getTrueValue() == ICI->getOperand(1) &&
- SI->getFalseValue() == ICI->getOperand(0)) {
- switch (ICI->getPredicate()) {
- default: return SPF_UNKNOWN; // Equality.
- case ICmpInst::ICMP_UGT:
- case ICmpInst::ICMP_UGE: return SPF_UMIN;
- case ICmpInst::ICMP_SGT:
- case ICmpInst::ICMP_SGE: return SPF_SMIN;
- case ICmpInst::ICMP_ULT:
- case ICmpInst::ICMP_ULE: return SPF_UMAX;
- case ICmpInst::ICMP_SLT:
- case ICmpInst::ICMP_SLE: return SPF_SMAX;
+ if (TrueVal == CmpRHS && FalseVal == CmpLHS) {
+ switch (Pred) {
+ default: return SPF_UNKNOWN; // Equality.
+ case ICmpInst::ICMP_UGT:
+ case ICmpInst::ICMP_UGE: return SPF_UMIN;
+ case ICmpInst::ICMP_SGT:
+ case ICmpInst::ICMP_SGE: return SPF_SMIN;
+ case ICmpInst::ICMP_ULT:
+ case ICmpInst::ICMP_ULE: return SPF_UMAX;
+ case ICmpInst::ICMP_SLT:
+ case ICmpInst::ICMP_SLE: return SPF_SMAX;
+ }
+ }
+
+ if (ConstantInt *C1 = dyn_cast<ConstantInt>(CmpRHS)) {
+ if ((CmpLHS == TrueVal && match(FalseVal, m_Neg(m_Specific(CmpLHS)))) ||
+ (CmpLHS == FalseVal && match(TrueVal, m_Neg(m_Specific(CmpLHS))))) {
+
+ // ABS(X) ==> (X >s 0) ? X : -X and (X >s -1) ? X : -X
+ // NABS(X) ==> (X >s 0) ? -X : X and (X >s -1) ? -X : X
+ if (Pred == ICmpInst::ICMP_SGT && (C1->isZero() || C1->isMinusOne())) {
+ return (CmpLHS == TrueVal) ? SPF_ABS : SPF_NABS;
+ }
+
+ // ABS(X) ==> (X <s 0) ? -X : X and (X <s 1) ? -X : X
+ // NABS(X) ==> (X <s 0) ? X : -X and (X <s 1) ? X : -X
+ if (Pred == ICmpInst::ICMP_SLT && (C1->isZero() || C1->isOne())) {
+ return (CmpLHS == FalseVal) ? SPF_ABS : SPF_NABS;
+ }
}
}
if (TI->isCast()) {
Type *FIOpndTy = FI->getOperand(0)->getType();
if (TI->getOperand(0)->getType() != FIOpndTy)
- return 0;
+ return nullptr;
// The select condition may be a vector. We may only change the operand
// type if the vector width remains the same (and matches the condition).
Type *CondTy = SI.getCondition()->getType();
if (CondTy->isVectorTy() && (!FIOpndTy->isVectorTy() ||
CondTy->getVectorNumElements() != FIOpndTy->getVectorNumElements()))
- return 0;
+ return nullptr;
} else {
- return 0; // unknown unary op.
+ return nullptr; // unknown unary op.
}
// Fold this by inserting a select from the input values.
// Only handle binary operators here.
if (!isa<BinaryOperator>(TI))
- return 0;
+ return nullptr;
// Figure out if the operations have any operands in common.
Value *MatchOp, *OtherOpT, *OtherOpF;
OtherOpF = FI->getOperand(0);
MatchIsOpZero = false;
} else if (!TI->isCommutative()) {
- return 0;
+ return nullptr;
} else if (TI->getOperand(0) == FI->getOperand(1)) {
MatchOp = TI->getOperand(0);
OtherOpT = TI->getOperand(1);
OtherOpF = FI->getOperand(1);
MatchIsOpZero = true;
} else {
- return 0;
+ return nullptr;
}
// If we reach here, they do have operations in common.
}
}
- return 0;
+ return nullptr;
}
/// SimplifyWithOpReplaced - See if V simplifies when its operand Op is
Instruction *I = dyn_cast<Instruction>(V);
if (!I)
- return 0;
+ return nullptr;
// If this is a binary operator, try to simplify it with the replaced op.
if (BinaryOperator *B = dyn_cast<BinaryOperator>(I)) {
}
}
- return 0;
+ return nullptr;
}
/// foldSelectICmpAndOr - We want to turn:
/// 1. The icmp predicate is inverted
/// 2. The select operands are reversed
/// 3. The magnitude of C2 and C1 are flipped
-static Value *foldSelectICmpAndOr(const SelectInst &SI, Value *TrueVal,
+///
+/// This also tries to turn
+/// --- Single bit tests:
+/// if ((x & C) == 0) x |= C to x |= C
+/// if ((x & C) != 0) x ^= C to x &= ~C
+/// if ((x & C) == 0) x ^= C to x |= C
+/// if ((x & C) != 0) x &= ~C to x &= ~C
+/// if ((x & C) == 0) x &= ~C to nothing
+static Value *foldSelectICmpAndOr(SelectInst &SI, Value *TrueVal,
Value *FalseVal,
InstCombiner::BuilderTy *Builder) {
const ICmpInst *IC = dyn_cast<ICmpInst>(SI.getCondition());
if (!IC || !IC->isEquality() || !SI.getType()->isIntegerTy())
- return 0;
+ return nullptr;
Value *CmpLHS = IC->getOperand(0);
Value *CmpRHS = IC->getOperand(1);
if (!match(CmpRHS, m_Zero()))
- return 0;
+ return nullptr;
Value *X;
const APInt *C1;
if (!match(CmpLHS, m_And(m_Value(X), m_Power2(C1))))
- return 0;
+ return nullptr;
const APInt *C2;
+ if (match(TrueVal, m_Specific(X))) {
+ // if ((X & C) != 0) X ^= C becomes X &= ~C
+ if (match(FalseVal, m_Xor(m_Specific(X), m_APInt(C2))) && C1 == C2)
+ return Builder->CreateAnd(X, ~(*C1));
+ // if ((X & C) != 0) X &= ~C becomes X &= ~C
+ if (match(FalseVal, m_And(m_Specific(X), m_APInt(C2))) && *C1 == ~(*C2))
+ return FalseVal;
+ } else if (match(FalseVal, m_Specific(X))) {
+ // if ((X & C) == 0) X ^= C becomes X |= C
+ if (match(TrueVal, m_Xor(m_Specific(X), m_APInt(C2))) && C1 == C2)
+ return Builder->CreateOr(X, *C1);
+ // if ((X & C) == 0) X &= ~C becomes nothing
+ if (match(TrueVal, m_And(m_Specific(X), m_APInt(C2))) && *C1 == ~(*C2))
+ return X;
+ // if ((X & C) == 0) X |= C becomes X |= C
+ if (match(TrueVal, m_Or(m_Specific(X), m_APInt(C2))) && C1 == C2)
+ return TrueVal;
+ }
+
bool OrOnTrueVal = false;
bool OrOnFalseVal = match(FalseVal, m_Or(m_Specific(TrueVal), m_Power2(C2)));
if (!OrOnFalseVal)
OrOnTrueVal = match(TrueVal, m_Or(m_Specific(FalseVal), m_Power2(C2)));
if (!OrOnFalseVal && !OrOnTrueVal)
- return 0;
+ return nullptr;
Value *V = CmpLHS;
Value *Y = OrOnFalseVal ? TrueVal : FalseVal;
if (IntegerType *Ty = dyn_cast<IntegerType>(CmpLHS->getType())) {
if (TrueVal->getType() == Ty) {
if (ConstantInt *Cmp = dyn_cast<ConstantInt>(CmpRHS)) {
- ConstantInt *C1 = NULL, *C2 = NULL;
+ ConstantInt *C1 = nullptr, *C2 = nullptr;
if (Pred == ICmpInst::ICMP_SGT && Cmp->isAllOnesValue()) {
C1 = dyn_cast<ConstantInt>(TrueVal);
C2 = dyn_cast<ConstantInt>(FalseVal);
if (Value *V = foldSelectICmpAndOr(SI, TrueVal, FalseVal, Builder))
return ReplaceInstUsesWith(SI, V);
- return Changed ? &SI : 0;
+ return Changed ? &SI : nullptr;
}
// If the value is a non-instruction value like a constant or argument, it
// can always be mapped.
const Instruction *I = dyn_cast<Instruction>(V);
- if (I == 0) return true;
+ if (!I) return true;
// If V is a PHI node defined in the same block as the condition PHI, we can
// map the arguments.
return ReplaceInstUsesWith(Outer, C);
}
- // TODO: MIN(MIN(A, 23), 97)
- return 0;
-}
+ if (SPF1 == SPF2) {
+ if (ConstantInt *CB = dyn_cast<ConstantInt>(B)) {
+ if (ConstantInt *CC = dyn_cast<ConstantInt>(C)) {
+ APInt ACB = CB->getValue();
+ APInt ACC = CC->getValue();
+
+ // MIN(MIN(A, 23), 97) -> MIN(A, 23)
+ // MAX(MAX(A, 97), 23) -> MAX(A, 97)
+ if ((SPF1 == SPF_UMIN && ACB.ule(ACC)) ||
+ (SPF1 == SPF_SMIN && ACB.sle(ACC)) ||
+ (SPF1 == SPF_UMAX && ACB.uge(ACC)) ||
+ (SPF1 == SPF_SMAX && ACB.sge(ACC)))
+ return ReplaceInstUsesWith(Outer, Inner);
+
+ // MIN(MIN(A, 97), 23) -> MIN(A, 23)
+ // MAX(MAX(A, 23), 97) -> MAX(A, 97)
+ if ((SPF1 == SPF_UMIN && ACB.ugt(ACC)) ||
+ (SPF1 == SPF_SMIN && ACB.sgt(ACC)) ||
+ (SPF1 == SPF_UMAX && ACB.ult(ACC)) ||
+ (SPF1 == SPF_SMAX && ACB.slt(ACC))) {
+ Outer.replaceUsesOfWith(Inner, A);
+ return &Outer;
+ }
+ }
+ }
+ }
+ // ABS(ABS(X)) -> ABS(X)
+ // NABS(NABS(X)) -> NABS(X)
+ if (SPF1 == SPF2 && (SPF1 == SPF_ABS || SPF1 == SPF_NABS)) {
+ return ReplaceInstUsesWith(Outer, Inner);
+ }
+
+ // ABS(NABS(X)) -> ABS(X)
+ // NABS(ABS(X)) -> NABS(X)
+ if ((SPF1 == SPF_ABS && SPF2 == SPF_NABS) ||
+ (SPF1 == SPF_NABS && SPF2 == SPF_ABS)) {
+ SelectInst *SI = cast<SelectInst>(Inner);
+ Value *NewSI = Builder->CreateSelect(
+ SI->getCondition(), SI->getFalseValue(), SI->getTrueValue());
+ return ReplaceInstUsesWith(Outer, NewSI);
+ }
+ return nullptr;
+}
/// foldSelectICmpAnd - If one of the constants is zero (we know they can't
/// both be) and we have an icmp instruction with zero, and we have an 'and'
InstCombiner::BuilderTy *Builder) {
const ICmpInst *IC = dyn_cast<ICmpInst>(SI.getCondition());
if (!IC || !IC->isEquality() || !SI.getType()->isIntegerTy())
- return 0;
+ return nullptr;
if (!match(IC->getOperand(1), m_Zero()))
- return 0;
+ return nullptr;
ConstantInt *AndRHS;
Value *LHS = IC->getOperand(0);
if (!match(LHS, m_And(m_Value(), m_ConstantInt(AndRHS))))
- return 0;
+ return nullptr;
// If both select arms are non-zero see if we have a select of the form
// 'x ? 2^n + C : C'. Then we can offset both arms by C, use the logic
// for 'x ? 2^n : 0' and fix the thing up at the end.
- ConstantInt *Offset = 0;
+ ConstantInt *Offset = nullptr;
if (!TrueVal->isZero() && !FalseVal->isZero()) {
if ((TrueVal->getValue() - FalseVal->getValue()).isPowerOf2())
Offset = FalseVal;
else if ((FalseVal->getValue() - TrueVal->getValue()).isPowerOf2())
Offset = TrueVal;
else
- return 0;
+ return nullptr;
// Adjust TrueVal and FalseVal to the offset.
TrueVal = ConstantInt::get(Builder->getContext(),
if (!AndRHS->getValue().isPowerOf2() ||
(!TrueVal->getValue().isPowerOf2() &&
!FalseVal->getValue().isPowerOf2()))
- return 0;
+ return nullptr;
// Determine which shift is needed to transform result of the 'and' into the
// desired result.
// or a trunc of the 'and'. The trunc case requires that all of the truncated
// bits are zero, we can figure that out by looking at the 'and' mask.
if (AndZeros >= ValC->getBitWidth())
- return 0;
+ return nullptr;
Value *V = Builder->CreateZExtOrTrunc(LHS, SI.getType());
if (ValZeros > AndZeros)
if (Instruction *TI = dyn_cast<Instruction>(TrueVal))
if (Instruction *FI = dyn_cast<Instruction>(FalseVal))
if (TI->hasOneUse() && FI->hasOneUse()) {
- Instruction *AddOp = 0, *SubOp = 0;
+ Instruction *AddOp = nullptr, *SubOp = nullptr;
// Turn (select C, (op X, Y), (op X, Z)) -> (op X, (select C, Y, Z))
if (TI->getOpcode() == FI->getOpcode())
}
if (AddOp) {
- Value *OtherAddOp = 0;
+ Value *OtherAddOp = nullptr;
if (SubOp->getOperand(0) == AddOp->getOperand(0)) {
OtherAddOp = AddOp->getOperand(1);
} else if (SubOp->getOperand(0) == AddOp->getOperand(1)) {
// TODO.
// ABS(-X) -> ABS(X)
- // ABS(ABS(X)) -> ABS(X)
}
// See if we can fold the select into a phi node if the condition is a select.
if (SelectInst *TrueSI = dyn_cast<SelectInst>(TrueVal)) {
if (TrueSI->getCondition() == CondVal) {
if (SI.getTrueValue() == TrueSI->getTrueValue())
- return 0;
+ return nullptr;
SI.setOperand(1, TrueSI->getTrueValue());
return &SI;
}
if (SelectInst *FalseSI = dyn_cast<SelectInst>(FalseVal)) {
if (FalseSI->getCondition() == CondVal) {
if (SI.getFalseValue() == FalseSI->getFalseValue())
- return 0;
+ return nullptr;
SI.setOperand(2, FalseSI->getFalseValue());
return &SI;
}
}
}
- return 0;
+ return nullptr;
}
projects / oota-llvm.git / blobdiff