diff options
Diffstat (limited to 'lib')
| -rw-r--r-- | lib/IR/DataLayout.cpp | 7 | ||||
| -rw-r--r-- | lib/Transforms/InstCombine/InstCombineCompares.cpp | 31 |
2 files changed, 27 insertions, 11 deletions
diff --git a/lib/IR/DataLayout.cpp b/lib/IR/DataLayout.cpp index 9596674912..ecd5216f20 100644 --- a/lib/IR/DataLayout.cpp +++ b/lib/IR/DataLayout.cpp @@ -621,6 +621,13 @@ Type *DataLayout::getIntPtrType(Type *Ty) const { return IntTy; } +Type *DataLayout::getSmallestLegalIntType(LLVMContext &C, unsigned Width) const { + for (unsigned i = 0, e = (unsigned)LegalIntWidths.size(); i != e; ++i) + if (Width <= LegalIntWidths[i]) + return Type::getIntNTy(C, LegalIntWidths[i]); + return 0; +} + uint64_t DataLayout::getIndexedOffset(Type *ptrTy, ArrayRef<Value *> Indices) const { Type *Ty = ptrTy; diff --git a/lib/Transforms/InstCombine/InstCombineCompares.cpp b/lib/Transforms/InstCombine/InstCombineCompares.cpp index 32fdb9b708..a4e117e4c4 100644 --- a/lib/Transforms/InstCombine/InstCombineCompares.cpp +++ b/lib/Transforms/InstCombine/InstCombineCompares.cpp @@ -443,20 +443,29 @@ FoldCmpLoadFromIndexedGlobal(GetElementPtrInst *GEP, GlobalVariable *GV, } - // If a 32-bit or 64-bit magic bitvector captures the entire comparison state + // If a magic bitvector captures the entire comparison state // of this load, replace it with computation that does: // ((magic_cst >> i) & 1) != 0 - if (ArrayElementCount <= 32 || - (TD && ArrayElementCount <= 64 && TD->isLegalInteger(64))) { - Type *Ty; - if (ArrayElementCount <= 32) + { + Type *Ty = 0; + + // Look for an appropriate type: + // - The type of Idx if the magic fits + // - The smallest fitting legal type if we have a DataLayout + // - Default to i32 + if (ArrayElementCount <= Idx->getType()->getIntegerBitWidth()) + Ty = Idx->getType(); + else if (TD) + Ty = TD->getSmallestLegalIntType(Init->getContext(), ArrayElementCount); + else if (ArrayElementCount <= 32) Ty = Type::getInt32Ty(Init->getContext()); - else - Ty = Type::getInt64Ty(Init->getContext()); - Value *V = Builder->CreateIntCast(Idx, Ty, false); - V = Builder->CreateLShr(ConstantInt::get(Ty, MagicBitvector), V); - V = Builder->CreateAnd(ConstantInt::get(Ty, 1), V); - return new ICmpInst(ICmpInst::ICMP_NE, V, ConstantInt::get(Ty, 0)); + + if (Ty != 0) { + Value *V = Builder->CreateIntCast(Idx, Ty, false); + V = Builder->CreateLShr(ConstantInt::get(Ty, MagicBitvector), V); + V = Builder->CreateAnd(ConstantInt::get(Ty, 1), V); + return new ICmpInst(ICmpInst::ICMP_NE, V, ConstantInt::get(Ty, 0)); + } } return 0; |