diff options
Diffstat (limited to 'llvm/lib/Analysis/InstructionSimplify.cpp')
| -rw-r--r-- | llvm/lib/Analysis/InstructionSimplify.cpp | 57 |
1 files changed, 42 insertions, 15 deletions
diff --git a/llvm/lib/Analysis/InstructionSimplify.cpp b/llvm/lib/Analysis/InstructionSimplify.cpp index 1e8a1dd..b34aede 100644 --- a/llvm/lib/Analysis/InstructionSimplify.cpp +++ b/llvm/lib/Analysis/InstructionSimplify.cpp @@ -2613,21 +2613,48 @@ static Value *SimplifyICmpInst(unsigned Predicate, Value *LHS, Value *RHS, } } - // icmp pred (or X, Y), X - if (LBO && match(LBO, m_CombineOr(m_Or(m_Value(), m_Specific(RHS)), - m_Or(m_Specific(RHS), m_Value())))) { - if (Pred == ICmpInst::ICMP_ULT) - return getFalse(ITy); - if (Pred == ICmpInst::ICMP_UGE) - return getTrue(ITy); - } - // icmp pred X, (or X, Y) - if (RBO && match(RBO, m_CombineOr(m_Or(m_Value(), m_Specific(LHS)), - m_Or(m_Specific(LHS), m_Value())))) { - if (Pred == ICmpInst::ICMP_ULE) - return getTrue(ITy); - if (Pred == ICmpInst::ICMP_UGT) - return getFalse(ITy); + { + Value *Y = nullptr; + // icmp pred (or X, Y), X + if (LBO && match(LBO, m_c_Or(m_Value(Y), m_Specific(RHS)))) { + if (Pred == ICmpInst::ICMP_ULT) + return getFalse(ITy); + if (Pred == ICmpInst::ICMP_UGE) + return getTrue(ITy); + + if (Pred == ICmpInst::ICMP_SLT || Pred == ICmpInst::ICMP_SGE) { + bool RHSKnownNonNegative, RHSKnownNegative; + bool YKnownNonNegative, YKnownNegative; + ComputeSignBit(RHS, RHSKnownNonNegative, RHSKnownNegative, Q.DL, 0, + Q.AC, Q.CxtI, Q.DT); + ComputeSignBit(Y, YKnownNonNegative, YKnownNegative, Q.DL, 0, Q.AC, + Q.CxtI, Q.DT); + if (RHSKnownNonNegative && YKnownNegative) + return Pred == ICmpInst::ICMP_SLT ? getTrue(ITy) : getFalse(ITy); + if (RHSKnownNegative || YKnownNonNegative) + return Pred == ICmpInst::ICMP_SLT ? getFalse(ITy) : getTrue(ITy); + } + } + // icmp pred X, (or X, Y) + if (RBO && match(RBO, m_c_Or(m_Value(Y), m_Specific(LHS)))) { + if (Pred == ICmpInst::ICMP_ULE) + return getTrue(ITy); + if (Pred == ICmpInst::ICMP_UGT) + return getFalse(ITy); + + if (Pred == ICmpInst::ICMP_SGT || Pred == ICmpInst::ICMP_SLE) { + bool LHSKnownNonNegative, LHSKnownNegative; + bool YKnownNonNegative, YKnownNegative; + ComputeSignBit(LHS, LHSKnownNonNegative, LHSKnownNegative, Q.DL, 0, + Q.AC, Q.CxtI, Q.DT); + ComputeSignBit(Y, YKnownNonNegative, YKnownNegative, Q.DL, 0, Q.AC, + Q.CxtI, Q.DT); + if (LHSKnownNonNegative && YKnownNegative) + return Pred == ICmpInst::ICMP_SGT ? getTrue(ITy) : getFalse(ITy); + if (LHSKnownNegative || YKnownNonNegative) + return Pred == ICmpInst::ICMP_SGT ? getFalse(ITy) : getTrue(ITy); + } + } } // icmp pred (and X, Y), X |