diff options
Diffstat (limited to 'llvm/lib/Analysis/ValueTracking.cpp')
| -rw-r--r-- | llvm/lib/Analysis/ValueTracking.cpp | 19 |
1 files changed, 15 insertions, 4 deletions
diff --git a/llvm/lib/Analysis/ValueTracking.cpp b/llvm/lib/Analysis/ValueTracking.cpp index 6bcc844..dfa3ecd 100644 --- a/llvm/lib/Analysis/ValueTracking.cpp +++ b/llvm/lib/Analysis/ValueTracking.cpp @@ -6003,12 +6003,24 @@ void computeKnownFPClass(const Value *V, const APInt &DemandedElts, if (IncValue == P) continue; + Instruction *CxtI = P->getIncomingBlock(U)->getTerminator(); + // If the Use is a select of this phi, use the fp class of the other - // operand to break the recursion. + // operand to break the recursion. Same around 2-operand phi nodes Value *V; if (match(IncValue, m_Select(m_Value(), m_Specific(P), m_Value(V))) || - match(IncValue, m_Select(m_Value(), m_Value(V), m_Specific(P)))) + match(IncValue, m_Select(m_Value(), m_Value(V), m_Specific(P)))) { IncValue = V; + } else if (auto *IncPhi = dyn_cast<PHINode>(IncValue); + IncPhi && IncPhi->getNumIncomingValues() == 2) { + for (int Idx = 0; Idx < 2; ++Idx) { + if (IncPhi->getIncomingValue(Idx) == P) { + IncValue = IncPhi->getIncomingValue(1 - Idx); + CxtI = IncPhi->getIncomingBlock(1 - Idx)->getTerminator(); + break; + } + } + } KnownFPClass KnownSrc; // Recurse, but cap the recursion to two levels, because we don't want @@ -6016,8 +6028,7 @@ void computeKnownFPClass(const Value *V, const APInt &DemandedElts, // detect known sign bits. computeKnownFPClass(IncValue, DemandedElts, InterestedClasses, KnownSrc, PhiRecursionLimit, - Q.getWithoutCondContext().getWithInstruction( - P->getIncomingBlock(U)->getTerminator())); + Q.getWithoutCondContext().getWithInstruction(CxtI)); if (First) { Known = KnownSrc; |