diff options
| -rw-r--r-- | llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp | 52 |
1 files changed, 23 insertions, 29 deletions
diff --git a/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp b/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp index b69aaa8db9f..9d94b276bf0 100644 --- a/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp +++ b/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp @@ -2213,15 +2213,15 @@ Instruction *InstCombiner::foldICmpEqualityWithConstant(ICmpInst &ICI) { const APInt &RHSV = RHS->getValue(); bool isICMP_NE = ICI.getPredicate() == ICmpInst::ICMP_NE; + Value *BOp0 = BO->getOperand(0), *BOp1 = BO->getOperand(1); switch (BO->getOpcode()) { case Instruction::SRem: // If we have a signed (X % (2^c)) == 0, turn it into an unsigned one. - if (RHSV == 0 && isa<ConstantInt>(BO->getOperand(1)) && BO->hasOneUse()) { - const APInt &V = cast<ConstantInt>(BO->getOperand(1))->getValue(); + if (RHSV == 0 && isa<ConstantInt>(BOp1) && BO->hasOneUse()) { + const APInt &V = cast<ConstantInt>(BOp1)->getValue(); if (V.sgt(1) && V.isPowerOf2()) { - Value *NewRem = Builder->CreateURem(BO->getOperand(0), - BO->getOperand(1), BO->getName()); + Value *NewRem = Builder->CreateURem(BOp0, BOp1, BO->getName()); return new ICmpInst(ICI.getPredicate(), NewRem, Constant::getNullValue(BO->getType())); } @@ -2229,15 +2229,13 @@ Instruction *InstCombiner::foldICmpEqualityWithConstant(ICmpInst &ICI) { break; case Instruction::Add: // Replace ((add A, B) != C) with (A != C-B) if B & C are constants. - if (ConstantInt *BOp1C = dyn_cast<ConstantInt>(BO->getOperand(1))) { + if (ConstantInt *BOp1C = dyn_cast<ConstantInt>(BOp1)) { if (BO->hasOneUse()) - return new ICmpInst(ICI.getPredicate(), BO->getOperand(0), + return new ICmpInst(ICI.getPredicate(), BOp0, ConstantExpr::getSub(RHS, BOp1C)); } else if (RHSV == 0) { // Replace ((add A, B) != 0) with (A != -B) if A or B is // efficiently invertible, or if the add has just this one use. - Value *BOp0 = BO->getOperand(0), *BOp1 = BO->getOperand(1); - if (Value *NegVal = dyn_castNegVal(BOp1)) return new ICmpInst(ICI.getPredicate(), BOp0, NegVal); if (Value *NegVal = dyn_castNegVal(BOp0)) @@ -2251,35 +2249,33 @@ Instruction *InstCombiner::foldICmpEqualityWithConstant(ICmpInst &ICI) { break; case Instruction::Xor: if (BO->hasOneUse()) { - if (Constant *BOC = dyn_cast<Constant>(BO->getOperand(1))) { + if (Constant *BOC = dyn_cast<Constant>(BOp1)) { // For the xor case, we can xor two constants together, eliminating // the explicit xor. - return new ICmpInst(ICI.getPredicate(), BO->getOperand(0), + return new ICmpInst(ICI.getPredicate(), BOp0, ConstantExpr::getXor(RHS, BOC)); } else if (RHSV == 0) { // Replace ((xor A, B) != 0) with (A != B) - return new ICmpInst(ICI.getPredicate(), BO->getOperand(0), - BO->getOperand(1)); + return new ICmpInst(ICI.getPredicate(), BOp0, BOp1); } } break; case Instruction::Sub: if (BO->hasOneUse()) { - if (ConstantInt *BOp0C = dyn_cast<ConstantInt>(BO->getOperand(0))) { + if (ConstantInt *BOp0C = dyn_cast<ConstantInt>(BOp0)) { // Replace ((sub A, B) != C) with (B != A-C) if A & C are constants. - return new ICmpInst(ICI.getPredicate(), BO->getOperand(1), + return new ICmpInst(ICI.getPredicate(), BOp1, ConstantExpr::getSub(BOp0C, RHS)); } else if (RHSV == 0) { // Replace ((sub A, B) != 0) with (A != B) - return new ICmpInst(ICI.getPredicate(), BO->getOperand(0), - BO->getOperand(1)); + return new ICmpInst(ICI.getPredicate(), BOp0, BOp1); } } break; case Instruction::Or: // If bits are being or'd in that are not present in the constant we // are comparing against, then the comparison could never succeed! - if (ConstantInt *BOC = dyn_cast<ConstantInt>(BO->getOperand(1))) { + if (ConstantInt *BOC = dyn_cast<ConstantInt>(BOp1)) { Constant *NotCI = ConstantExpr::getNot(RHS); if (!ConstantExpr::getAnd(BOC, NotCI)->isNullValue()) return replaceInstUsesWith(ICI, Builder->getInt1(isICMP_NE)); @@ -2289,14 +2285,14 @@ Instruction *InstCombiner::foldICmpEqualityWithConstant(ICmpInst &ICI) { // This removes the -1 constant. if (BO->hasOneUse() && RHS->isAllOnesValue()) { Constant *NotBOC = ConstantExpr::getNot(BOC); - Value *And = Builder->CreateAnd(BO->getOperand(0), NotBOC); + Value *And = Builder->CreateAnd(BOp0, NotBOC); return new ICmpInst(ICI.getPredicate(), And, NotBOC); } } break; case Instruction::And: - if (ConstantInt *BOC = dyn_cast<ConstantInt>(BO->getOperand(1))) { + if (ConstantInt *BOC = dyn_cast<ConstantInt>(BOp1)) { // If bits are being compared against that are and'd out, then the // comparison can never succeed! if ((RHSV & ~BOC->getValue()) != 0) @@ -2313,31 +2309,29 @@ Instruction *InstCombiner::foldICmpEqualityWithConstant(ICmpInst &ICI) { // Replace (and X, (1 << size(X)-1) != 0) with x s< 0 if (BOC->getValue().isSignBit()) { - Value *X = BO->getOperand(0); - Constant *Zero = Constant::getNullValue(X->getType()); - ICmpInst::Predicate pred = + Constant *Zero = Constant::getNullValue(BOp0->getType()); + ICmpInst::Predicate Pred = isICMP_NE ? ICmpInst::ICMP_SLT : ICmpInst::ICMP_SGE; - return new ICmpInst(pred, X, Zero); + return new ICmpInst(Pred, BOp0, Zero); } // ((X & ~7) == 0) --> X < 8 if (RHSV == 0 && isHighOnes(BOC)) { - Value *X = BO->getOperand(0); Constant *NegX = ConstantExpr::getNeg(BOC); - ICmpInst::Predicate pred = + ICmpInst::Predicate Pred = isICMP_NE ? ICmpInst::ICMP_UGE : ICmpInst::ICMP_ULT; - return new ICmpInst(pred, X, NegX); + return new ICmpInst(Pred, BOp0, NegX); } } break; case Instruction::Mul: if (RHSV == 0 && BO->hasNoSignedWrap()) { - if (ConstantInt *BOC = dyn_cast<ConstantInt>(BO->getOperand(1))) { + if (ConstantInt *BOC = dyn_cast<ConstantInt>(BOp1)) { // The trivial case (mul X, 0) is handled by InstSimplify // General case : (mul X, C) != 0 iff X != 0 // (mul X, C) == 0 iff X == 0 if (!BOC->isZero()) - return new ICmpInst(ICI.getPredicate(), BO->getOperand(0), + return new ICmpInst(ICI.getPredicate(), BOp0, Constant::getNullValue(RHS->getType())); } } @@ -2347,7 +2341,7 @@ Instruction *InstCombiner::foldICmpEqualityWithConstant(ICmpInst &ICI) { // (icmp eq/ne (udiv A, B), 0) -> (icmp ugt/ule i32 B, A) ICmpInst::Predicate Pred = isICMP_NE ? ICmpInst::ICMP_ULE : ICmpInst::ICMP_UGT; - return new ICmpInst(Pred, BO->getOperand(1), BO->getOperand(0)); + return new ICmpInst(Pred, BOp1, BOp0); } break; default: |
