diff options
Diffstat (limited to 'llvm/lib/Analysis/InstructionSimplify.cpp')
| -rw-r--r-- | llvm/lib/Analysis/InstructionSimplify.cpp | 30 |
1 files changed, 30 insertions, 0 deletions
diff --git a/llvm/lib/Analysis/InstructionSimplify.cpp b/llvm/lib/Analysis/InstructionSimplify.cpp index 770fdf9054c..f1ec7b36a93 100644 --- a/llvm/lib/Analysis/InstructionSimplify.cpp +++ b/llvm/lib/Analysis/InstructionSimplify.cpp @@ -3433,7 +3433,37 @@ static Value *SimplifyFCmpInst(unsigned Predicate, Value *LHS, Value *RHS, break; } } + + // Check comparison of constant with minnum with smaller constant. + // TODO: Add the related transform for maxnum. + const APFloat *MinC; + if (match(LHS, + m_Intrinsic<Intrinsic::minnum>(m_Value(), m_APFloat(MinC))) && + MinC->compare(*C) == APFloat::cmpLessThan) { + // The 'less-than' relationship and minnum guarantee that we do not have + // NaN constants, so ordered and unordered preds are handled the same. + switch (Pred) { + case FCmpInst::FCMP_OEQ: case FCmpInst::FCMP_UEQ: + case FCmpInst::FCMP_OGE: case FCmpInst::FCMP_UGE: + case FCmpInst::FCMP_OGT: case FCmpInst::FCMP_UGT: + // minnum(X, LesserC) == C --> false + // minnum(X, LesserC) >= C --> false + // minnum(X, LesserC) > C --> false + return getFalse(RetTy); + case FCmpInst::FCMP_ONE: case FCmpInst::FCMP_UNE: + case FCmpInst::FCMP_OLE: case FCmpInst::FCMP_ULE: + case FCmpInst::FCMP_OLT: case FCmpInst::FCMP_ULT: + // minnum(X, LesserC) != C --> true + // minnum(X, LesserC) <= C --> true + // minnum(X, LesserC) < C --> true + return getTrue(RetTy); + default: + // TRUE/FALSE/ORD/UNO should be handled before this. + llvm_unreachable("Unexpected fcmp predicate"); + } + } } + if (match(RHS, m_AnyZeroFP())) { switch (Pred) { case FCmpInst::FCMP_OGE: |
