diff options
Diffstat (limited to 'llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp')
| -rw-r--r-- | llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp | 23 |
1 files changed, 9 insertions, 14 deletions
diff --git a/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp b/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp index 192dad0994c..6c795db6669 100644 --- a/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp +++ b/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp @@ -176,12 +176,6 @@ static bool isSignTest(ICmpInst::Predicate &Pred, const ConstantInt *RHS) { return false; } -/// Return true if the constant is of the form 1+0+. This is the same as -/// lowones(~X). -static bool isHighOnes(const ConstantInt *CI) { - return (~CI->getValue() + 1).isPowerOf2(); -} - /// Given a signed integer type and a set of known zero and one bits, compute /// the maximum and minimum values that could have the specified known zero and /// known one bits, returning them in Min/Max. @@ -2288,11 +2282,11 @@ Instruction *InstCombiner::foldICmpEqualityWithConstant(ICmpInst &ICI) { } break; } - case Instruction::And: - // FIXME: Vectors are excluded by ConstantInt. - if (ConstantInt *BOC = dyn_cast<ConstantInt>(BOp1)) { + case Instruction::And: { + const APInt *BOC; + if (match(BOp1, m_APInt(BOC))) { // If we have ((X & C) == C), turn it into ((X & C) != 0). - if (RHS == BOC && RHSV->isPowerOf2()) + if (RHSV == BOC && RHSV->isPowerOf2()) return new ICmpInst(isICMP_NE ? ICmpInst::ICMP_EQ : ICmpInst::ICMP_NE, BO, Constant::getNullValue(RHS->getType())); @@ -2301,7 +2295,7 @@ Instruction *InstCombiner::foldICmpEqualityWithConstant(ICmpInst &ICI) { break; // Replace (and X, (1 << size(X)-1) != 0) with x s< 0 - if (BOC->getValue().isSignBit()) { + if (BOC->isSignBit()) { Constant *Zero = Constant::getNullValue(BOp0->getType()); ICmpInst::Predicate Pred = isICMP_NE ? ICmpInst::ICMP_SLT : ICmpInst::ICMP_SGE; @@ -2309,14 +2303,15 @@ Instruction *InstCombiner::foldICmpEqualityWithConstant(ICmpInst &ICI) { } // ((X & ~7) == 0) --> X < 8 - if (*RHSV == 0 && isHighOnes(BOC)) { - Constant *NegX = ConstantExpr::getNeg(BOC); + if (*RHSV == 0 && (~(*BOC) + 1).isPowerOf2()) { + Constant *NegBOC = ConstantExpr::getNeg(cast<Constant>(BOp1)); ICmpInst::Predicate Pred = isICMP_NE ? ICmpInst::ICMP_UGE : ICmpInst::ICMP_ULT; - return new ICmpInst(Pred, BOp0, NegX); + return new ICmpInst(Pred, BOp0, NegBOC); } } break; + } case Instruction::Mul: if (*RHSV == 0 && BO->hasNoSignedWrap()) { // FIXME: Vectors are excluded by ConstantInt. |
