diff options
Diffstat (limited to 'lib/Transforms/InstCombine/InstCombineCasts.cpp')
| -rw-r--r-- | lib/Transforms/InstCombine/InstCombineCasts.cpp | 9 |
1 files changed, 5 insertions, 4 deletions
diff --git a/lib/Transforms/InstCombine/InstCombineCasts.cpp b/lib/Transforms/InstCombine/InstCombineCasts.cpp index 52c36ddd3f..c5ddec8b75 100644 --- a/lib/Transforms/InstCombine/InstCombineCasts.cpp +++ b/lib/Transforms/InstCombine/InstCombineCasts.cpp @@ -165,9 +165,8 @@ Instruction *InstCombiner::PromoteCastOfAllocation(BitCastInst &CI, /// If CastOpc is a sext or zext, we are asking if the low bits of the value can /// bit computed in a larger type, which is then and'd or sext_in_reg'd to get /// the final result. -bool InstCombiner::CanEvaluateInDifferentType(Value *V, const Type *Ty, - unsigned CastOpc, - int &NumCastsRemoved){ +static bool CanEvaluateInDifferentType(Value *V, const Type *Ty, + unsigned CastOpc, int &NumCastsRemoved) { // We can always evaluate constants in another type. if (isa<Constant>(V)) return true; @@ -274,7 +273,9 @@ bool InstCombiner::CanEvaluateInDifferentType(Value *V, const Type *Ty, NumCastsRemoved); } case Instruction::PHI: { - // We can change a phi if we can change all operands. + // We can change a phi if we can change all operands. Note that we never + // get into trouble with cyclic PHIs here because we only consider + // instructions with a single use. PHINode *PN = cast<PHINode>(I); for (unsigned i = 0, e = PN->getNumIncomingValues(); i != e; ++i) if (!CanEvaluateInDifferentType(PN->getIncomingValue(i), Ty, CastOpc, |