ICmpInst *ICI = dyn_cast<ICmpInst>(SI->getCondition());
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;
+ }
}
}
return nullptr;
const APInt *C2;
-
- // if ((x & C) != 0) x ^= C becomes x &= ~C
- if (match(FalseVal, m_Xor(m_Specific(TrueVal), m_APInt(C2))) && C1 == C2) {
- return Builder->CreateAnd(TrueVal, ~(*C1));
- }
-
- // if ((x & C) == 0) x ^= C becomes x |= C
- if (match(TrueVal, m_Xor(m_Specific(FalseVal), m_APInt(C2))) && C1 == C2) {
- return Builder->CreateOr(FalseVal, *C1);
- }
-
- // if ((x & C) != 0) x &= ~C becomes x &= ~C
- // if ((x & C) == 0) x &= ~C becomes nothing
- if ((match(FalseVal, m_And(m_Specific(TrueVal), m_APInt(C2))) ||
- match(TrueVal, m_And(m_Specific(FalseVal), m_APInt(C2)))) &&
- *C1 == ~(*C2)) {
- return FalseVal;
+ 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 OrOnFalseVal = false;
- bool OrOnTrueVal = match(TrueVal, m_Or(m_Specific(FalseVal), m_Power2(C2)));
-
- // if ((x & C) == 0) x |= C becomes x |= C
- if (OrOnTrueVal && C1 == C2)
- return TrueVal;
-
- if (!OrOnTrueVal)
- OrOnFalseVal = match(FalseVal, m_Or(m_Specific(TrueVal), m_Power2(C2)));
+ 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 nullptr;
return ReplaceInstUsesWith(Outer, C);
}
- // MIN(MIN(A, 23), 97) -> MIN(A, 23)
- // MAX(MAX(A, 97), 23) -> MAX(A, 97)
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;
+ }
}
}
}
- // TODO: MIN(MIN(A, 97), 23) -> MIN(A, 23)
- // TODO: MAX(MAX(A, 23), 97) -> MAX(A, 97)
+ // 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;
}
// 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.
projects / oota-llvm.git / blobdiff