diff options
Diffstat (limited to 'llvm/lib')
| -rw-r--r-- | llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp | 12 |
1 files changed, 12 insertions, 0 deletions
diff --git a/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp b/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp index 9ce1c3fc41b..905f66a380f 100644 --- a/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp +++ b/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp @@ -3490,6 +3490,18 @@ Instruction *InstCombiner::visitICmpInst(ICmpInst &I) { } } } + + if (BO0) { + // Transform A & (L - 1) `ult` L --> L != 0 + auto LSubOne = m_Add(m_Specific(Op1), m_AllOnes()); + auto BitwiseAnd = + m_CombineOr(m_And(m_Value(), LSubOne), m_And(LSubOne, m_Value())); + + if (match(BO0, BitwiseAnd) && I.getPredicate() == ICmpInst::ICMP_ULT) { + auto *Zero = Constant::getNullValue(BO0->getType()); + return new ICmpInst(ICmpInst::ICMP_NE, Op1, Zero); + } + } } { Value *A, *B; |

