diff options
Diffstat (limited to 'llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp')
| -rw-r--r-- | llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp | 26 |
1 files changed, 21 insertions, 5 deletions
diff --git a/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp b/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp index d98f966f8ca..639d8319e0d 100644 --- a/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp +++ b/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp @@ -612,9 +612,10 @@ Instruction *InstCombiner::FoldGEPICmp(GEPOperator *GEPLHS, Value *RHS, if (ICmpInst::isSigned(Cond)) return nullptr; - // Look through bitcasts. - if (BitCastInst *BCI = dyn_cast<BitCastInst>(RHS)) - RHS = BCI->getOperand(0); + // Look through bitcasts and addrspacecasts. We do not however want to remove + // 0 GEPs. + if (!isa<GetElementPtrInst>(RHS)) + RHS = RHS->stripPointerCasts(); Value *PtrBase = GEPLHS->getOperand(0); if (DL && PtrBase == RHS && GEPLHS->isInBounds()) { @@ -655,9 +656,24 @@ Instruction *InstCombiner::FoldGEPICmp(GEPOperator *GEPLHS, Value *RHS, (GEPRHS->hasAllConstantIndices() || GEPRHS->hasOneUse()) && PtrBase->stripPointerCasts() == GEPRHS->getOperand(0)->stripPointerCasts()) { + Value *LOffset = EmitGEPOffset(GEPLHS); + Value *ROffset = EmitGEPOffset(GEPRHS); + + // If we looked through an addrspacecast between different sized address + // spaces, the LHS and RHS pointers are different sized + // integers. Truncate to the smaller one. + Type *LHSIndexTy = LOffset->getType(); + Type *RHSIndexTy = ROffset->getType(); + if (LHSIndexTy != RHSIndexTy) { + if (LHSIndexTy->getPrimitiveSizeInBits() < + RHSIndexTy->getPrimitiveSizeInBits()) { + ROffset = Builder->CreateTrunc(ROffset, LHSIndexTy); + } else + LOffset = Builder->CreateTrunc(LOffset, RHSIndexTy); + } + Value *Cmp = Builder->CreateICmp(ICmpInst::getSignedPredicate(Cond), - EmitGEPOffset(GEPLHS), - EmitGEPOffset(GEPRHS)); + LOffset, ROffset); return ReplaceInstUsesWith(I, Cmp); } |
