diff options
| -rw-r--r-- | lib/Transforms/InstCombine/InstCombineCasts.cpp | 20 |
1 files changed, 14 insertions, 6 deletions
diff --git a/lib/Transforms/InstCombine/InstCombineCasts.cpp b/lib/Transforms/InstCombine/InstCombineCasts.cpp index 939c2b1..b5da3e6 100644 --- a/lib/Transforms/InstCombine/InstCombineCasts.cpp +++ b/lib/Transforms/InstCombine/InstCombineCasts.cpp @@ -325,8 +325,11 @@ static bool CanEvaluateTruncated(Value *V, const Type *Ty) { const Type *OrigTy = V->getType(); - // If this is an extension from the dest type, we can eliminate it. - if ((isa<ZExtInst>(I) || isa<SExtInst>(I)) && + // If this is an extension from the dest type, we can eliminate it, even if it + // has multiple uses. + // FIXME: This is currently disabled until codegen can handle this without + // pessimizing code, PR5997. + if (0 && (isa<ZExtInst>(I) || isa<SExtInst>(I)) && I->getOperand(0)->getType() == Ty) return true; @@ -606,8 +609,10 @@ static bool CanEvaluateZExtd(Value *V, const Type *Ty, unsigned &BitsToClear) { if (!I) return false; // If the input is a truncate from the destination type, we can trivially - // eliminate it. - if (isa<TruncInst>(I) && I->getOperand(0)->getType() == Ty) + // eliminate it, even if it has multiple uses. + // FIXME: This is currently disabled until codegen can handle this without + // pessimizing code, PR5997. + if (0 && isa<TruncInst>(I) && I->getOperand(0)->getType() == Ty) return true; // We can't extend or shrink something that has multiple uses: doing so would @@ -853,8 +858,11 @@ static bool CanEvaluateSExtd(Value *V, const Type *Ty) { Instruction *I = dyn_cast<Instruction>(V); if (!I) return false; - // If this is a truncate from the dest type, we can trivially eliminate it. - if (isa<TruncInst>(I) && I->getOperand(0)->getType() == Ty) + // If this is a truncate from the dest type, we can trivially eliminate it, + // even if it has multiple uses. + // FIXME: This is currently disabled until codegen can handle this without + // pessimizing code, PR5997. + if (0 && isa<TruncInst>(I) && I->getOperand(0)->getType() == Ty) return true; // We can't extend or shrink something that has multiple uses: doing so would |