| //===- InstCombineCalls.cpp -----------------------------------------------===// |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file is distributed under the University of Illinois Open Source |
| // License. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // This file implements the visitCall and visitInvoke functions. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "InstCombine.h" |
| #include "llvm/Support/CallSite.h" |
| #include "llvm/Target/TargetData.h" |
| #include "llvm/Analysis/MemoryBuiltins.h" |
| #include "llvm/Transforms/Utils/BuildLibCalls.h" |
| #include "llvm/Transforms/Utils/Local.h" |
| using namespace llvm; |
| |
| /// getPromotedType - Return the specified type promoted as it would be to pass |
| /// though a va_arg area. |
| static Type *getPromotedType(Type *Ty) { |
| if (IntegerType* ITy = dyn_cast<IntegerType>(Ty)) { |
| if (ITy->getBitWidth() < 32) |
| return Type::getInt32Ty(Ty->getContext()); |
| } |
| return Ty; |
| } |
| |
| |
| Instruction *InstCombiner::SimplifyMemTransfer(MemIntrinsic *MI) { |
| unsigned DstAlign = getKnownAlignment(MI->getArgOperand(0), TD); |
| unsigned SrcAlign = getKnownAlignment(MI->getArgOperand(1), TD); |
| unsigned MinAlign = std::min(DstAlign, SrcAlign); |
| unsigned CopyAlign = MI->getAlignment(); |
| |
| if (CopyAlign < MinAlign) { |
| MI->setAlignment(ConstantInt::get(MI->getAlignmentType(), |
| MinAlign, false)); |
| return MI; |
| } |
| |
| // If MemCpyInst length is 1/2/4/8 bytes then replace memcpy with |
| // load/store. |
| ConstantInt *MemOpLength = dyn_cast<ConstantInt>(MI->getArgOperand(2)); |
| if (MemOpLength == 0) return 0; |
| |
| // Source and destination pointer types are always "i8*" for intrinsic. See |
| // if the size is something we can handle with a single primitive load/store. |
| // A single load+store correctly handles overlapping memory in the memmove |
| // case. |
| unsigned Size = MemOpLength->getZExtValue(); |
| if (Size == 0) return MI; // Delete this mem transfer. |
| |
| if (Size > 8 || (Size&(Size-1))) |
| return 0; // If not 1/2/4/8 bytes, exit. |
| |
| // Use an integer load+store unless we can find something better. |
| unsigned SrcAddrSp = |
| cast<PointerType>(MI->getArgOperand(1)->getType())->getAddressSpace(); |
| unsigned DstAddrSp = |
| cast<PointerType>(MI->getArgOperand(0)->getType())->getAddressSpace(); |
| |
| IntegerType* IntType = IntegerType::get(MI->getContext(), Size<<3); |
| Type *NewSrcPtrTy = PointerType::get(IntType, SrcAddrSp); |
| Type *NewDstPtrTy = PointerType::get(IntType, DstAddrSp); |
| |
| // Memcpy forces the use of i8* for the source and destination. That means |
| // that if you're using memcpy to move one double around, you'll get a cast |
| // from double* to i8*. We'd much rather use a double load+store rather than |
| // an i64 load+store, here because this improves the odds that the source or |
| // dest address will be promotable. See if we can find a better type than the |
| // integer datatype. |
| Value *StrippedDest = MI->getArgOperand(0)->stripPointerCasts(); |
| if (StrippedDest != MI->getArgOperand(0)) { |
| Type *SrcETy = cast<PointerType>(StrippedDest->getType()) |
| ->getElementType(); |
| if (TD && SrcETy->isSized() && TD->getTypeStoreSize(SrcETy) == Size) { |
| // The SrcETy might be something like {{{double}}} or [1 x double]. Rip |
| // down through these levels if so. |
| while (!SrcETy->isSingleValueType()) { |
| if (StructType *STy = dyn_cast<StructType>(SrcETy)) { |
| if (STy->getNumElements() == 1) |
| SrcETy = STy->getElementType(0); |
| else |
| break; |
| } else if (ArrayType *ATy = dyn_cast<ArrayType>(SrcETy)) { |
| if (ATy->getNumElements() == 1) |
| SrcETy = ATy->getElementType(); |
| else |
| break; |
| } else |
| break; |
| } |
| |
| if (SrcETy->isSingleValueType()) { |
| NewSrcPtrTy = PointerType::get(SrcETy, SrcAddrSp); |
| NewDstPtrTy = PointerType::get(SrcETy, DstAddrSp); |
| } |
| } |
| } |
| |
| |
| // If the memcpy/memmove provides better alignment info than we can |
| // infer, use it. |
| SrcAlign = std::max(SrcAlign, CopyAlign); |
| DstAlign = std::max(DstAlign, CopyAlign); |
| |
| Value *Src = Builder->CreateBitCast(MI->getArgOperand(1), NewSrcPtrTy); |
| Value *Dest = Builder->CreateBitCast(MI->getArgOperand(0), NewDstPtrTy); |
| LoadInst *L = Builder->CreateLoad(Src, MI->isVolatile()); |
| L->setAlignment(SrcAlign); |
| StoreInst *S = Builder->CreateStore(L, Dest, MI->isVolatile()); |
| S->setAlignment(DstAlign); |
| |
| // Set the size of the copy to 0, it will be deleted on the next iteration. |
| MI->setArgOperand(2, Constant::getNullValue(MemOpLength->getType())); |
| return MI; |
| } |
| |
| Instruction *InstCombiner::SimplifyMemSet(MemSetInst *MI) { |
| unsigned Alignment = getKnownAlignment(MI->getDest(), TD); |
| if (MI->getAlignment() < Alignment) { |
| MI->setAlignment(ConstantInt::get(MI->getAlignmentType(), |
| Alignment, false)); |
| return MI; |
| } |
| |
| // Extract the length and alignment and fill if they are constant. |
| ConstantInt *LenC = dyn_cast<ConstantInt>(MI->getLength()); |
| ConstantInt *FillC = dyn_cast<ConstantInt>(MI->getValue()); |
| if (!LenC || !FillC || !FillC->getType()->isIntegerTy(8)) |
| return 0; |
| uint64_t Len = LenC->getZExtValue(); |
| Alignment = MI->getAlignment(); |
| |
| // If the length is zero, this is a no-op |
| if (Len == 0) return MI; // memset(d,c,0,a) -> noop |
| |
| // memset(s,c,n) -> store s, c (for n=1,2,4,8) |
| if (Len <= 8 && isPowerOf2_32((uint32_t)Len)) { |
| Type *ITy = IntegerType::get(MI->getContext(), Len*8); // n=1 -> i8. |
| |
| Value *Dest = MI->getDest(); |
| unsigned DstAddrSp = cast<PointerType>(Dest->getType())->getAddressSpace(); |
| Type *NewDstPtrTy = PointerType::get(ITy, DstAddrSp); |
| Dest = Builder->CreateBitCast(Dest, NewDstPtrTy); |
| |
| // Alignment 0 is identity for alignment 1 for memset, but not store. |
| if (Alignment == 0) Alignment = 1; |
| |
| // Extract the fill value and store. |
| uint64_t Fill = FillC->getZExtValue()*0x0101010101010101ULL; |
| StoreInst *S = Builder->CreateStore(ConstantInt::get(ITy, Fill), Dest, |
| MI->isVolatile()); |
| S->setAlignment(Alignment); |
| |
| // Set the size of the copy to 0, it will be deleted on the next iteration. |
| MI->setLength(Constant::getNullValue(LenC->getType())); |
| return MI; |
| } |
| |
| return 0; |
| } |
| |
| /// visitCallInst - CallInst simplification. This mostly only handles folding |
| /// of intrinsic instructions. For normal calls, it allows visitCallSite to do |
| /// the heavy lifting. |
| /// |
| Instruction *InstCombiner::visitCallInst(CallInst &CI) { |
| if (isFreeCall(&CI)) |
| return visitFree(CI); |
| if (isMalloc(&CI)) |
| return visitMalloc(CI); |
| |
| // If the caller function is nounwind, mark the call as nounwind, even if the |
| // callee isn't. |
| if (CI.getParent()->getParent()->doesNotThrow() && |
| !CI.doesNotThrow()) { |
| CI.setDoesNotThrow(); |
| return &CI; |
| } |
| |
| IntrinsicInst *II = dyn_cast<IntrinsicInst>(&CI); |
| if (!II) return visitCallSite(&CI); |
| |
| // Intrinsics cannot occur in an invoke, so handle them here instead of in |
| // visitCallSite. |
| if (MemIntrinsic *MI = dyn_cast<MemIntrinsic>(II)) { |
| bool Changed = false; |
| |
| // memmove/cpy/set of zero bytes is a noop. |
| if (Constant *NumBytes = dyn_cast<Constant>(MI->getLength())) { |
| if (NumBytes->isNullValue()) |
| return EraseInstFromFunction(CI); |
| |
| if (ConstantInt *CI = dyn_cast<ConstantInt>(NumBytes)) |
| if (CI->getZExtValue() == 1) { |
| // Replace the instruction with just byte operations. We would |
| // transform other cases to loads/stores, but we don't know if |
| // alignment is sufficient. |
| } |
| } |
| |
| // No other transformations apply to volatile transfers. |
| if (MI->isVolatile()) |
| return 0; |
| |
| // If we have a memmove and the source operation is a constant global, |
| // then the source and dest pointers can't alias, so we can change this |
| // into a call to memcpy. |
| if (MemMoveInst *MMI = dyn_cast<MemMoveInst>(MI)) { |
| if (GlobalVariable *GVSrc = dyn_cast<GlobalVariable>(MMI->getSource())) |
| if (GVSrc->isConstant()) { |
| Module *M = CI.getParent()->getParent()->getParent(); |
| Intrinsic::ID MemCpyID = Intrinsic::memcpy; |
| Type *Tys[3] = { CI.getArgOperand(0)->getType(), |
| CI.getArgOperand(1)->getType(), |
| CI.getArgOperand(2)->getType() }; |
| CI.setCalledFunction(Intrinsic::getDeclaration(M, MemCpyID, Tys)); |
| Changed = true; |
| } |
| } |
| |
| if (MemTransferInst *MTI = dyn_cast<MemTransferInst>(MI)) { |
| // memmove(x,x,size) -> noop. |
| if (MTI->getSource() == MTI->getDest()) |
| return EraseInstFromFunction(CI); |
| } |
| |
| // If we can determine a pointer alignment that is bigger than currently |
| // set, update the alignment. |
| if (isa<MemTransferInst>(MI)) { |
| if (Instruction *I = SimplifyMemTransfer(MI)) |
| return I; |
| } else if (MemSetInst *MSI = dyn_cast<MemSetInst>(MI)) { |
| if (Instruction *I = SimplifyMemSet(MSI)) |
| return I; |
| } |
| |
| if (Changed) return II; |
| } |
| |
| switch (II->getIntrinsicID()) { |
| default: break; |
| case Intrinsic::objectsize: { |
| // We need target data for just about everything so depend on it. |
| if (!TD) break; |
| |
| Type *ReturnTy = CI.getType(); |
| uint64_t DontKnow = II->getArgOperand(1) == Builder->getTrue() ? 0 : -1ULL; |
| |
| // Get to the real allocated thing and offset as fast as possible. |
| Value *Op1 = II->getArgOperand(0)->stripPointerCasts(); |
| |
| uint64_t Offset = 0; |
| uint64_t Size = -1ULL; |
| |
| // Try to look through constant GEPs. |
| if (GEPOperator *GEP = dyn_cast<GEPOperator>(Op1)) { |
| if (!GEP->hasAllConstantIndices()) break; |
| |
| // Get the current byte offset into the thing. Use the original |
| // operand in case we're looking through a bitcast. |
| SmallVector<Value*, 8> Ops(GEP->idx_begin(), GEP->idx_end()); |
| if (!GEP->getPointerOperandType()->isPointerTy()) |
| return 0; |
| Offset = TD->getIndexedOffset(GEP->getPointerOperandType(), Ops); |
| |
| Op1 = GEP->getPointerOperand()->stripPointerCasts(); |
| |
| // Make sure we're not a constant offset from an external |
| // global. |
| if (GlobalVariable *GV = dyn_cast<GlobalVariable>(Op1)) |
| if (!GV->hasDefinitiveInitializer()) break; |
| } |
| |
| // If we've stripped down to a single global variable that we |
| // can know the size of then just return that. |
| if (GlobalVariable *GV = dyn_cast<GlobalVariable>(Op1)) { |
| if (GV->hasDefinitiveInitializer()) { |
| Constant *C = GV->getInitializer(); |
| Size = TD->getTypeAllocSize(C->getType()); |
| } else { |
| // Can't determine size of the GV. |
| Constant *RetVal = ConstantInt::get(ReturnTy, DontKnow); |
| return ReplaceInstUsesWith(CI, RetVal); |
| } |
| } else if (AllocaInst *AI = dyn_cast<AllocaInst>(Op1)) { |
| // Get alloca size. |
| if (AI->getAllocatedType()->isSized()) { |
| Size = TD->getTypeAllocSize(AI->getAllocatedType()); |
| if (AI->isArrayAllocation()) { |
| const ConstantInt *C = dyn_cast<ConstantInt>(AI->getArraySize()); |
| if (!C) break; |
| Size *= C->getZExtValue(); |
| } |
| } |
| } else if (CallInst *MI = extractMallocCall(Op1)) { |
| // Get allocation size. |
| Type* MallocType = getMallocAllocatedType(MI); |
| if (MallocType && MallocType->isSized()) |
| if (Value *NElems = getMallocArraySize(MI, TD, true)) |
| if (ConstantInt *NElements = dyn_cast<ConstantInt>(NElems)) |
| Size = NElements->getZExtValue() * TD->getTypeAllocSize(MallocType); |
| } |
| |
| // Do not return "I don't know" here. Later optimization passes could |
| // make it possible to evaluate objectsize to a constant. |
| if (Size == -1ULL) |
| break; |
| |
| if (Size < Offset) { |
| // Out of bound reference? Negative index normalized to large |
| // index? Just return "I don't know". |
| return ReplaceInstUsesWith(CI, ConstantInt::get(ReturnTy, DontKnow)); |
| } |
| return ReplaceInstUsesWith(CI, ConstantInt::get(ReturnTy, Size-Offset)); |
| } |
| case Intrinsic::bswap: |
| // bswap(bswap(x)) -> x |
| if (IntrinsicInst *Operand = dyn_cast<IntrinsicInst>(II->getArgOperand(0))) |
| if (Operand->getIntrinsicID() == Intrinsic::bswap) |
| return ReplaceInstUsesWith(CI, Operand->getArgOperand(0)); |
| |
| // bswap(trunc(bswap(x))) -> trunc(lshr(x, c)) |
| if (TruncInst *TI = dyn_cast<TruncInst>(II->getArgOperand(0))) { |
| if (IntrinsicInst *Operand = dyn_cast<IntrinsicInst>(TI->getOperand(0))) |
| if (Operand->getIntrinsicID() == Intrinsic::bswap) { |
| unsigned C = Operand->getType()->getPrimitiveSizeInBits() - |
| TI->getType()->getPrimitiveSizeInBits(); |
| Value *CV = ConstantInt::get(Operand->getType(), C); |
| Value *V = Builder->CreateLShr(Operand->getArgOperand(0), CV); |
| return new TruncInst(V, TI->getType()); |
| } |
| } |
| |
| break; |
| case Intrinsic::powi: |
| if (ConstantInt *Power = dyn_cast<ConstantInt>(II->getArgOperand(1))) { |
| // powi(x, 0) -> 1.0 |
| if (Power->isZero()) |
| return ReplaceInstUsesWith(CI, ConstantFP::get(CI.getType(), 1.0)); |
| // powi(x, 1) -> x |
| if (Power->isOne()) |
| return ReplaceInstUsesWith(CI, II->getArgOperand(0)); |
| // powi(x, -1) -> 1/x |
| if (Power->isAllOnesValue()) |
| return BinaryOperator::CreateFDiv(ConstantFP::get(CI.getType(), 1.0), |
| II->getArgOperand(0)); |
| } |
| break; |
| case Intrinsic::cttz: { |
| // If all bits below the first known one are known zero, |
| // this value is constant. |
| IntegerType *IT = dyn_cast<IntegerType>(II->getArgOperand(0)->getType()); |
| // FIXME: Try to simplify vectors of integers. |
| if (!IT) break; |
| uint32_t BitWidth = IT->getBitWidth(); |
| APInt KnownZero(BitWidth, 0); |
| APInt KnownOne(BitWidth, 0); |
| ComputeMaskedBits(II->getArgOperand(0), APInt::getAllOnesValue(BitWidth), |
| KnownZero, KnownOne); |
| unsigned TrailingZeros = KnownOne.countTrailingZeros(); |
| APInt Mask(APInt::getLowBitsSet(BitWidth, TrailingZeros)); |
| if ((Mask & KnownZero) == Mask) |
| return ReplaceInstUsesWith(CI, ConstantInt::get(IT, |
| APInt(BitWidth, TrailingZeros))); |
| |
| } |
| break; |
| case Intrinsic::ctlz: { |
| // If all bits above the first known one are known zero, |
| // this value is constant. |
| IntegerType *IT = dyn_cast<IntegerType>(II->getArgOperand(0)->getType()); |
| // FIXME: Try to simplify vectors of integers. |
| if (!IT) break; |
| uint32_t BitWidth = IT->getBitWidth(); |
| APInt KnownZero(BitWidth, 0); |
| APInt KnownOne(BitWidth, 0); |
| ComputeMaskedBits(II->getArgOperand(0), APInt::getAllOnesValue(BitWidth), |
| KnownZero, KnownOne); |
| unsigned LeadingZeros = KnownOne.countLeadingZeros(); |
| APInt Mask(APInt::getHighBitsSet(BitWidth, LeadingZeros)); |
| if ((Mask & KnownZero) == Mask) |
| return ReplaceInstUsesWith(CI, ConstantInt::get(IT, |
| APInt(BitWidth, LeadingZeros))); |
| |
| } |
| break; |
| case Intrinsic::uadd_with_overflow: { |
| Value *LHS = II->getArgOperand(0), *RHS = II->getArgOperand(1); |
| IntegerType *IT = cast<IntegerType>(II->getArgOperand(0)->getType()); |
| uint32_t BitWidth = IT->getBitWidth(); |
| APInt Mask = APInt::getSignBit(BitWidth); |
| APInt LHSKnownZero(BitWidth, 0); |
| APInt LHSKnownOne(BitWidth, 0); |
| ComputeMaskedBits(LHS, Mask, LHSKnownZero, LHSKnownOne); |
| bool LHSKnownNegative = LHSKnownOne[BitWidth - 1]; |
| bool LHSKnownPositive = LHSKnownZero[BitWidth - 1]; |
| |
| if (LHSKnownNegative || LHSKnownPositive) { |
| APInt RHSKnownZero(BitWidth, 0); |
| APInt RHSKnownOne(BitWidth, 0); |
| ComputeMaskedBits(RHS, Mask, RHSKnownZero, RHSKnownOne); |
| bool RHSKnownNegative = RHSKnownOne[BitWidth - 1]; |
| bool RHSKnownPositive = RHSKnownZero[BitWidth - 1]; |
| if (LHSKnownNegative && RHSKnownNegative) { |
| // The sign bit is set in both cases: this MUST overflow. |
| // Create a simple add instruction, and insert it into the struct. |
| Value *Add = Builder->CreateAdd(LHS, RHS); |
| Add->takeName(&CI); |
| Constant *V[] = { |
| UndefValue::get(LHS->getType()), |
| ConstantInt::getTrue(II->getContext()) |
| }; |
| StructType *ST = cast<StructType>(II->getType()); |
| Constant *Struct = ConstantStruct::get(ST, V); |
| return InsertValueInst::Create(Struct, Add, 0); |
| } |
| |
| if (LHSKnownPositive && RHSKnownPositive) { |
| // The sign bit is clear in both cases: this CANNOT overflow. |
| // Create a simple add instruction, and insert it into the struct. |
| Value *Add = Builder->CreateNUWAdd(LHS, RHS); |
| Add->takeName(&CI); |
| Constant *V[] = { |
| UndefValue::get(LHS->getType()), |
| ConstantInt::getFalse(II->getContext()) |
| }; |
| StructType *ST = cast<StructType>(II->getType()); |
| Constant *Struct = ConstantStruct::get(ST, V); |
| return InsertValueInst::Create(Struct, Add, 0); |
| } |
| } |
| } |
| // FALL THROUGH uadd into sadd |
| case Intrinsic::sadd_with_overflow: |
| // Canonicalize constants into the RHS. |
| if (isa<Constant>(II->getArgOperand(0)) && |
| !isa<Constant>(II->getArgOperand(1))) { |
| Value *LHS = II->getArgOperand(0); |
| II->setArgOperand(0, II->getArgOperand(1)); |
| II->setArgOperand(1, LHS); |
| return II; |
| } |
| |
| // X + undef -> undef |
| if (isa<UndefValue>(II->getArgOperand(1))) |
| return ReplaceInstUsesWith(CI, UndefValue::get(II->getType())); |
| |
| if (ConstantInt *RHS = dyn_cast<ConstantInt>(II->getArgOperand(1))) { |
| // X + 0 -> {X, false} |
| if (RHS->isZero()) { |
| Constant *V[] = { |
| UndefValue::get(II->getArgOperand(0)->getType()), |
| ConstantInt::getFalse(II->getContext()) |
| }; |
| Constant *Struct = |
| ConstantStruct::get(cast<StructType>(II->getType()), V); |
| return InsertValueInst::Create(Struct, II->getArgOperand(0), 0); |
| } |
| } |
| break; |
| case Intrinsic::usub_with_overflow: |
| case Intrinsic::ssub_with_overflow: |
| // undef - X -> undef |
| // X - undef -> undef |
| if (isa<UndefValue>(II->getArgOperand(0)) || |
| isa<UndefValue>(II->getArgOperand(1))) |
| return ReplaceInstUsesWith(CI, UndefValue::get(II->getType())); |
| |
| if (ConstantInt *RHS = dyn_cast<ConstantInt>(II->getArgOperand(1))) { |
| // X - 0 -> {X, false} |
| if (RHS->isZero()) { |
| Constant *V[] = { |
| UndefValue::get(II->getArgOperand(0)->getType()), |
| ConstantInt::getFalse(II->getContext()) |
| }; |
| Constant *Struct = |
| ConstantStruct::get(cast<StructType>(II->getType()), V); |
| return InsertValueInst::Create(Struct, II->getArgOperand(0), 0); |
| } |
| } |
| break; |
| case Intrinsic::umul_with_overflow: { |
| Value *LHS = II->getArgOperand(0), *RHS = II->getArgOperand(1); |
| unsigned BitWidth = cast<IntegerType>(LHS->getType())->getBitWidth(); |
| APInt Mask = APInt::getAllOnesValue(BitWidth); |
| |
| APInt LHSKnownZero(BitWidth, 0); |
| APInt LHSKnownOne(BitWidth, 0); |
| ComputeMaskedBits(LHS, Mask, LHSKnownZero, LHSKnownOne); |
| APInt RHSKnownZero(BitWidth, 0); |
| APInt RHSKnownOne(BitWidth, 0); |
| ComputeMaskedBits(RHS, Mask, RHSKnownZero, RHSKnownOne); |
| |
| // Get the largest possible values for each operand. |
| APInt LHSMax = ~LHSKnownZero; |
| APInt RHSMax = ~RHSKnownZero; |
| |
| // If multiplying the maximum values does not overflow then we can turn |
| // this into a plain NUW mul. |
| bool Overflow; |
| LHSMax.umul_ov(RHSMax, Overflow); |
| if (!Overflow) { |
| Value *Mul = Builder->CreateNUWMul(LHS, RHS, "umul_with_overflow"); |
| Constant *V[] = { |
| UndefValue::get(LHS->getType()), |
| Builder->getFalse() |
| }; |
| Constant *Struct = ConstantStruct::get(cast<StructType>(II->getType()),V); |
| return InsertValueInst::Create(Struct, Mul, 0); |
| } |
| } // FALL THROUGH |
| case Intrinsic::smul_with_overflow: |
| // Canonicalize constants into the RHS. |
| if (isa<Constant>(II->getArgOperand(0)) && |
| !isa<Constant>(II->getArgOperand(1))) { |
| Value *LHS = II->getArgOperand(0); |
| II->setArgOperand(0, II->getArgOperand(1)); |
| II->setArgOperand(1, LHS); |
| return II; |
| } |
| |
| // X * undef -> undef |
| if (isa<UndefValue>(II->getArgOperand(1))) |
| return ReplaceInstUsesWith(CI, UndefValue::get(II->getType())); |
| |
| if (ConstantInt *RHSI = dyn_cast<ConstantInt>(II->getArgOperand(1))) { |
| // X*0 -> {0, false} |
| if (RHSI->isZero()) |
| return ReplaceInstUsesWith(CI, Constant::getNullValue(II->getType())); |
| |
| // X * 1 -> {X, false} |
| if (RHSI->equalsInt(1)) { |
| Constant *V[] = { |
| UndefValue::get(II->getArgOperand(0)->getType()), |
| ConstantInt::getFalse(II->getContext()) |
| }; |
| Constant *Struct = |
| ConstantStruct::get(cast<StructType>(II->getType()), V); |
| return InsertValueInst::Create(Struct, II->getArgOperand(0), 0); |
| } |
| } |
| break; |
| case Intrinsic::ppc_altivec_lvx: |
| case Intrinsic::ppc_altivec_lvxl: |
| // Turn PPC lvx -> load if the pointer is known aligned. |
| if (getOrEnforceKnownAlignment(II->getArgOperand(0), 16, TD) >= 16) { |
| Value *Ptr = Builder->CreateBitCast(II->getArgOperand(0), |
| PointerType::getUnqual(II->getType())); |
| return new LoadInst(Ptr); |
| } |
| break; |
| case Intrinsic::ppc_altivec_stvx: |
| case Intrinsic::ppc_altivec_stvxl: |
| // Turn stvx -> store if the pointer is known aligned. |
| if (getOrEnforceKnownAlignment(II->getArgOperand(1), 16, TD) >= 16) { |
| Type *OpPtrTy = |
| PointerType::getUnqual(II->getArgOperand(0)->getType()); |
| Value *Ptr = Builder->CreateBitCast(II->getArgOperand(1), OpPtrTy); |
| return new StoreInst(II->getArgOperand(0), Ptr); |
| } |
| break; |
| case Intrinsic::x86_sse_storeu_ps: |
| case Intrinsic::x86_sse2_storeu_pd: |
| case Intrinsic::x86_sse2_storeu_dq: |
| // Turn X86 storeu -> store if the pointer is known aligned. |
| if (getOrEnforceKnownAlignment(II->getArgOperand(0), 16, TD) >= 16) { |
| Type *OpPtrTy = |
| PointerType::getUnqual(II->getArgOperand(1)->getType()); |
| Value *Ptr = Builder->CreateBitCast(II->getArgOperand(0), OpPtrTy); |
| return new StoreInst(II->getArgOperand(1), Ptr); |
| } |
| break; |
| |
| case Intrinsic::x86_sse_cvtss2si: |
| case Intrinsic::x86_sse_cvtss2si64: |
| case Intrinsic::x86_sse_cvttss2si: |
| case Intrinsic::x86_sse_cvttss2si64: |
| case Intrinsic::x86_sse2_cvtsd2si: |
| case Intrinsic::x86_sse2_cvtsd2si64: |
| case Intrinsic::x86_sse2_cvttsd2si: |
| case Intrinsic::x86_sse2_cvttsd2si64: { |
| // These intrinsics only demand the 0th element of their input vectors. If |
| // we can simplify the input based on that, do so now. |
| unsigned VWidth = |
| cast<VectorType>(II->getArgOperand(0)->getType())->getNumElements(); |
| APInt DemandedElts(VWidth, 1); |
| APInt UndefElts(VWidth, 0); |
| if (Value *V = SimplifyDemandedVectorElts(II->getArgOperand(0), |
| DemandedElts, UndefElts)) { |
| II->setArgOperand(0, V); |
| return II; |
| } |
| break; |
| } |
| |
| |
| case Intrinsic::x86_sse41_pmovsxbw: |
| case Intrinsic::x86_sse41_pmovsxwd: |
| case Intrinsic::x86_sse41_pmovsxdq: |
| case Intrinsic::x86_sse41_pmovzxbw: |
| case Intrinsic::x86_sse41_pmovzxwd: |
| case Intrinsic::x86_sse41_pmovzxdq: { |
| // pmov{s|z}x ignores the upper half of their input vectors. |
| unsigned VWidth = |
| cast<VectorType>(II->getArgOperand(0)->getType())->getNumElements(); |
| unsigned LowHalfElts = VWidth / 2; |
| APInt InputDemandedElts(APInt::getBitsSet(VWidth, 0, LowHalfElts)); |
| APInt UndefElts(VWidth, 0); |
| if (Value *TmpV = SimplifyDemandedVectorElts(II->getArgOperand(0), |
| InputDemandedElts, |
| UndefElts)) { |
| II->setArgOperand(0, TmpV); |
| return II; |
| } |
| break; |
| } |
| |
| case Intrinsic::ppc_altivec_vperm: |
| // Turn vperm(V1,V2,mask) -> shuffle(V1,V2,mask) if mask is a constant. |
| if (Constant *Mask = dyn_cast<Constant>(II->getArgOperand(2))) { |
| assert(Mask->getType()->getVectorNumElements() == 16 && |
| "Bad type for intrinsic!"); |
| |
| // Check that all of the elements are integer constants or undefs. |
| bool AllEltsOk = true; |
| for (unsigned i = 0; i != 16; ++i) { |
| Constant *Elt = Mask->getAggregateElement(i); |
| if (Elt == 0 || |
| !(isa<ConstantInt>(Elt) || isa<UndefValue>(Elt))) { |
| AllEltsOk = false; |
| break; |
| } |
| } |
| |
| if (AllEltsOk) { |
| // Cast the input vectors to byte vectors. |
| Value *Op0 = Builder->CreateBitCast(II->getArgOperand(0), |
| Mask->getType()); |
| Value *Op1 = Builder->CreateBitCast(II->getArgOperand(1), |
| Mask->getType()); |
| Value *Result = UndefValue::get(Op0->getType()); |
| |
| // Only extract each element once. |
| Value *ExtractedElts[32]; |
| memset(ExtractedElts, 0, sizeof(ExtractedElts)); |
| |
| for (unsigned i = 0; i != 16; ++i) { |
| if (isa<UndefValue>(Mask->getAggregateElement(i))) |
| continue; |
| unsigned Idx = |
| cast<ConstantInt>(Mask->getAggregateElement(i))->getZExtValue(); |
| Idx &= 31; // Match the hardware behavior. |
| |
| if (ExtractedElts[Idx] == 0) { |
| ExtractedElts[Idx] = |
| Builder->CreateExtractElement(Idx < 16 ? Op0 : Op1, |
| Builder->getInt32(Idx&15)); |
| } |
| |
| // Insert this value into the result vector. |
| Result = Builder->CreateInsertElement(Result, ExtractedElts[Idx], |
| Builder->getInt32(i)); |
| } |
| return CastInst::Create(Instruction::BitCast, Result, CI.getType()); |
| } |
| } |
| break; |
| |
| case Intrinsic::arm_neon_vld1: |
| case Intrinsic::arm_neon_vld2: |
| case Intrinsic::arm_neon_vld3: |
| case Intrinsic::arm_neon_vld4: |
| case Intrinsic::arm_neon_vld2lane: |
| case Intrinsic::arm_neon_vld3lane: |
| case Intrinsic::arm_neon_vld4lane: |
| case Intrinsic::arm_neon_vst1: |
| case Intrinsic::arm_neon_vst2: |
| case Intrinsic::arm_neon_vst3: |
| case Intrinsic::arm_neon_vst4: |
| case Intrinsic::arm_neon_vst2lane: |
| case Intrinsic::arm_neon_vst3lane: |
| case Intrinsic::arm_neon_vst4lane: { |
| unsigned MemAlign = getKnownAlignment(II->getArgOperand(0), TD); |
| unsigned AlignArg = II->getNumArgOperands() - 1; |
| ConstantInt *IntrAlign = dyn_cast<ConstantInt>(II->getArgOperand(AlignArg)); |
| if (IntrAlign && IntrAlign->getZExtValue() < MemAlign) { |
| II->setArgOperand(AlignArg, |
| ConstantInt::get(Type::getInt32Ty(II->getContext()), |
| MemAlign, false)); |
| return II; |
| } |
| break; |
| } |
| |
| case Intrinsic::stackrestore: { |
| // If the save is right next to the restore, remove the restore. This can |
| // happen when variable allocas are DCE'd. |
| if (IntrinsicInst *SS = dyn_cast<IntrinsicInst>(II->getArgOperand(0))) { |
| if (SS->getIntrinsicID() == Intrinsic::stacksave) { |
| BasicBlock::iterator BI = SS; |
| if (&*++BI == II) |
| return EraseInstFromFunction(CI); |
| } |
| } |
| |
| // Scan down this block to see if there is another stack restore in the |
| // same block without an intervening call/alloca. |
| BasicBlock::iterator BI = II; |
| TerminatorInst *TI = II->getParent()->getTerminator(); |
| bool CannotRemove = false; |
| for (++BI; &*BI != TI; ++BI) { |
| if (isa<AllocaInst>(BI) || isMalloc(BI)) { |
| CannotRemove = true; |
| break; |
| } |
| if (CallInst *BCI = dyn_cast<CallInst>(BI)) { |
| if (IntrinsicInst *II = dyn_cast<IntrinsicInst>(BCI)) { |
| // If there is a stackrestore below this one, remove this one. |
| if (II->getIntrinsicID() == Intrinsic::stackrestore) |
| return EraseInstFromFunction(CI); |
| // Otherwise, ignore the intrinsic. |
| } else { |
| // If we found a non-intrinsic call, we can't remove the stack |
| // restore. |
| CannotRemove = true; |
| break; |
| } |
| } |
| } |
| |
| // If the stack restore is in a return, resume, or unwind block and if there |
| // are no allocas or calls between the restore and the return, nuke the |
| // restore. |
| if (!CannotRemove && (isa<ReturnInst>(TI) || isa<ResumeInst>(TI) || |
| isa<UnwindInst>(TI))) |
| return EraseInstFromFunction(CI); |
| break; |
| } |
| } |
| |
| return visitCallSite(II); |
| } |
| |
| // InvokeInst simplification |
| // |
| Instruction *InstCombiner::visitInvokeInst(InvokeInst &II) { |
| return visitCallSite(&II); |
| } |
| |
| /// isSafeToEliminateVarargsCast - If this cast does not affect the value |
| /// passed through the varargs area, we can eliminate the use of the cast. |
| static bool isSafeToEliminateVarargsCast(const CallSite CS, |
| const CastInst * const CI, |
| const TargetData * const TD, |
| const int ix) { |
| if (!CI->isLosslessCast()) |
| return false; |
| |
| // The size of ByVal arguments is derived from the type, so we |
| // can't change to a type with a different size. If the size were |
| // passed explicitly we could avoid this check. |
| if (!CS.isByValArgument(ix)) |
| return true; |
| |
| Type* SrcTy = |
| cast<PointerType>(CI->getOperand(0)->getType())->getElementType(); |
| Type* DstTy = cast<PointerType>(CI->getType())->getElementType(); |
| if (!SrcTy->isSized() || !DstTy->isSized()) |
| return false; |
| if (!TD || TD->getTypeAllocSize(SrcTy) != TD->getTypeAllocSize(DstTy)) |
| return false; |
| return true; |
| } |
| |
| namespace { |
| class InstCombineFortifiedLibCalls : public SimplifyFortifiedLibCalls { |
| InstCombiner *IC; |
| protected: |
| void replaceCall(Value *With) { |
| NewInstruction = IC->ReplaceInstUsesWith(*CI, With); |
| } |
| bool isFoldable(unsigned SizeCIOp, unsigned SizeArgOp, bool isString) const { |
| if (CI->getArgOperand(SizeCIOp) == CI->getArgOperand(SizeArgOp)) |
| return true; |
| if (ConstantInt *SizeCI = |
| dyn_cast<ConstantInt>(CI->getArgOperand(SizeCIOp))) { |
| if (SizeCI->isAllOnesValue()) |
| return true; |
| if (isString) { |
| uint64_t Len = GetStringLength(CI->getArgOperand(SizeArgOp)); |
| // If the length is 0 we don't know how long it is and so we can't |
| // remove the check. |
| if (Len == 0) return false; |
| return SizeCI->getZExtValue() >= Len; |
| } |
| if (ConstantInt *Arg = dyn_cast<ConstantInt>( |
| CI->getArgOperand(SizeArgOp))) |
| return SizeCI->getZExtValue() >= Arg->getZExtValue(); |
| } |
| return false; |
| } |
| public: |
| InstCombineFortifiedLibCalls(InstCombiner *IC) : IC(IC), NewInstruction(0) { } |
| Instruction *NewInstruction; |
| }; |
| } // end anonymous namespace |
| |
| // Try to fold some different type of calls here. |
| // Currently we're only working with the checking functions, memcpy_chk, |
| // mempcpy_chk, memmove_chk, memset_chk, strcpy_chk, stpcpy_chk, strncpy_chk, |
| // strcat_chk and strncat_chk. |
| Instruction *InstCombiner::tryOptimizeCall(CallInst *CI, const TargetData *TD) { |
| if (CI->getCalledFunction() == 0) return 0; |
| |
| InstCombineFortifiedLibCalls Simplifier(this); |
| Simplifier.fold(CI, TD); |
| return Simplifier.NewInstruction; |
| } |
| |
| static IntrinsicInst *FindInitTrampolineFromAlloca(Value *TrampMem) { |
| // Strip off at most one level of pointer casts, looking for an alloca. This |
| // is good enough in practice and simpler than handling any number of casts. |
| Value *Underlying = TrampMem->stripPointerCasts(); |
| if (Underlying != TrampMem && |
| (!Underlying->hasOneUse() || *Underlying->use_begin() != TrampMem)) |
| return 0; |
| if (!isa<AllocaInst>(Underlying)) |
| return 0; |
| |
| IntrinsicInst *InitTrampoline = 0; |
| for (Value::use_iterator I = TrampMem->use_begin(), E = TrampMem->use_end(); |
| I != E; I++) { |
| IntrinsicInst *II = dyn_cast<IntrinsicInst>(*I); |
| if (!II) |
| return 0; |
| if (II->getIntrinsicID() == Intrinsic::init_trampoline) { |
| if (InitTrampoline) |
| // More than one init_trampoline writes to this value. Give up. |
| return 0; |
| InitTrampoline = II; |
| continue; |
| } |
| if (II->getIntrinsicID() == Intrinsic::adjust_trampoline) |
| // Allow any number of calls to adjust.trampoline. |
| continue; |
| return 0; |
| } |
| |
| // No call to init.trampoline found. |
| if (!InitTrampoline) |
| return 0; |
| |
| // Check that the alloca is being used in the expected way. |
| if (InitTrampoline->getOperand(0) != TrampMem) |
| return 0; |
| |
| return InitTrampoline; |
| } |
| |
| static IntrinsicInst *FindInitTrampolineFromBB(IntrinsicInst *AdjustTramp, |
| Value *TrampMem) { |
| // Visit all the previous instructions in the basic block, and try to find a |
| // init.trampoline which has a direct path to the adjust.trampoline. |
| for (BasicBlock::iterator I = AdjustTramp, |
| E = AdjustTramp->getParent()->begin(); I != E; ) { |
| Instruction *Inst = --I; |
| if (IntrinsicInst *II = dyn_cast<IntrinsicInst>(I)) |
| if (II->getIntrinsicID() == Intrinsic::init_trampoline && |
| II->getOperand(0) == TrampMem) |
| return II; |
| if (Inst->mayWriteToMemory()) |
| return 0; |
| } |
| return 0; |
| } |
| |
| // Given a call to llvm.adjust.trampoline, find and return the corresponding |
| // call to llvm.init.trampoline if the call to the trampoline can be optimized |
| // to a direct call to a function. Otherwise return NULL. |
| // |
| static IntrinsicInst *FindInitTrampoline(Value *Callee) { |
| Callee = Callee->stripPointerCasts(); |
| IntrinsicInst *AdjustTramp = dyn_cast<IntrinsicInst>(Callee); |
| if (!AdjustTramp || |
| AdjustTramp->getIntrinsicID() != Intrinsic::adjust_trampoline) |
| return 0; |
| |
| Value *TrampMem = AdjustTramp->getOperand(0); |
| |
| if (IntrinsicInst *IT = FindInitTrampolineFromAlloca(TrampMem)) |
| return IT; |
| if (IntrinsicInst *IT = FindInitTrampolineFromBB(AdjustTramp, TrampMem)) |
| return IT; |
| return 0; |
| } |
| |
| // visitCallSite - Improvements for call and invoke instructions. |
| // |
| Instruction *InstCombiner::visitCallSite(CallSite CS) { |
| bool Changed = false; |
| |
| // If the callee is a pointer to a function, attempt to move any casts to the |
| // arguments of the call/invoke. |
| Value *Callee = CS.getCalledValue(); |
| if (!isa<Function>(Callee) && transformConstExprCastCall(CS)) |
| return 0; |
| |
| if (Function *CalleeF = dyn_cast<Function>(Callee)) |
| // If the call and callee calling conventions don't match, this call must |
| // be unreachable, as the call is undefined. |
| if (CalleeF->getCallingConv() != CS.getCallingConv() && |
| // Only do this for calls to a function with a body. A prototype may |
| // not actually end up matching the implementation's calling conv for a |
| // variety of reasons (e.g. it may be written in assembly). |
| !CalleeF->isDeclaration()) { |
| Instruction *OldCall = CS.getInstruction(); |
| new StoreInst(ConstantInt::getTrue(Callee->getContext()), |
| UndefValue::get(Type::getInt1PtrTy(Callee->getContext())), |
| OldCall); |
| // If OldCall dues not return void then replaceAllUsesWith undef. |
| // This allows ValueHandlers and custom metadata to adjust itself. |
| if (!OldCall->getType()->isVoidTy()) |
| ReplaceInstUsesWith(*OldCall, UndefValue::get(OldCall->getType())); |
| if (isa<CallInst>(OldCall)) |
| return EraseInstFromFunction(*OldCall); |
| |
| // We cannot remove an invoke, because it would change the CFG, just |
| // change the callee to a null pointer. |
| cast<InvokeInst>(OldCall)->setCalledFunction( |
| Constant::getNullValue(CalleeF->getType())); |
| return 0; |
| } |
| |
| if (isa<ConstantPointerNull>(Callee) || isa<UndefValue>(Callee)) { |
| // This instruction is not reachable, just remove it. We insert a store to |
| // undef so that we know that this code is not reachable, despite the fact |
| // that we can't modify the CFG here. |
| new StoreInst(ConstantInt::getTrue(Callee->getContext()), |
| UndefValue::get(Type::getInt1PtrTy(Callee->getContext())), |
| CS.getInstruction()); |
| |
| // If CS does not return void then replaceAllUsesWith undef. |
| // This allows ValueHandlers and custom metadata to adjust itself. |
| if (!CS.getInstruction()->getType()->isVoidTy()) |
| ReplaceInstUsesWith(*CS.getInstruction(), |
| UndefValue::get(CS.getInstruction()->getType())); |
| |
| if (InvokeInst *II = dyn_cast<InvokeInst>(CS.getInstruction())) { |
| // Don't break the CFG, insert a dummy cond branch. |
| BranchInst::Create(II->getNormalDest(), II->getUnwindDest(), |
| ConstantInt::getTrue(Callee->getContext()), II); |
| } |
| return EraseInstFromFunction(*CS.getInstruction()); |
| } |
| |
| if (IntrinsicInst *II = FindInitTrampoline(Callee)) |
| return transformCallThroughTrampoline(CS, II); |
| |
| PointerType *PTy = cast<PointerType>(Callee->getType()); |
| FunctionType *FTy = cast<FunctionType>(PTy->getElementType()); |
| if (FTy->isVarArg()) { |
| int ix = FTy->getNumParams(); |
| // See if we can optimize any arguments passed through the varargs area of |
| // the call. |
| for (CallSite::arg_iterator I = CS.arg_begin()+FTy->getNumParams(), |
| E = CS.arg_end(); I != E; ++I, ++ix) { |
| CastInst *CI = dyn_cast<CastInst>(*I); |
| if (CI && isSafeToEliminateVarargsCast(CS, CI, TD, ix)) { |
| *I = CI->getOperand(0); |
| Changed = true; |
| } |
| } |
| } |
| |
| if (isa<InlineAsm>(Callee) && !CS.doesNotThrow()) { |
| // Inline asm calls cannot throw - mark them 'nounwind'. |
| CS.setDoesNotThrow(); |
| Changed = true; |
| } |
| |
| // Try to optimize the call if possible, we require TargetData for most of |
| // this. None of these calls are seen as possibly dead so go ahead and |
| // delete the instruction now. |
| if (CallInst *CI = dyn_cast<CallInst>(CS.getInstruction())) { |
| Instruction *I = tryOptimizeCall(CI, TD); |
| // If we changed something return the result, etc. Otherwise let |
| // the fallthrough check. |
| if (I) return EraseInstFromFunction(*I); |
| } |
| |
| return Changed ? CS.getInstruction() : 0; |
| } |
| |
| // transformConstExprCastCall - If the callee is a constexpr cast of a function, |
| // attempt to move the cast to the arguments of the call/invoke. |
| // |
| bool InstCombiner::transformConstExprCastCall(CallSite CS) { |
| Function *Callee = |
| dyn_cast<Function>(CS.getCalledValue()->stripPointerCasts()); |
| if (Callee == 0) |
| return false; |
| Instruction *Caller = CS.getInstruction(); |
| const AttrListPtr &CallerPAL = CS.getAttributes(); |
| |
| // Okay, this is a cast from a function to a different type. Unless doing so |
| // would cause a type conversion of one of our arguments, change this call to |
| // be a direct call with arguments casted to the appropriate types. |
| // |
| FunctionType *FT = Callee->getFunctionType(); |
| Type *OldRetTy = Caller->getType(); |
| Type *NewRetTy = FT->getReturnType(); |
| |
| if (NewRetTy->isStructTy()) |
| return false; // TODO: Handle multiple return values. |
| |
| // Check to see if we are changing the return type... |
| if (OldRetTy != NewRetTy) { |
| if (Callee->isDeclaration() && |
| // Conversion is ok if changing from one pointer type to another or from |
| // a pointer to an integer of the same size. |
| !((OldRetTy->isPointerTy() || !TD || |
| OldRetTy == TD->getIntPtrType(Caller->getContext())) && |
| (NewRetTy->isPointerTy() || !TD || |
| NewRetTy == TD->getIntPtrType(Caller->getContext())))) |
| return false; // Cannot transform this return value. |
| |
| if (!Caller->use_empty() && |
| // void -> non-void is handled specially |
| !NewRetTy->isVoidTy() && !CastInst::isCastable(NewRetTy, OldRetTy)) |
| return false; // Cannot transform this return value. |
| |
| if (!CallerPAL.isEmpty() && !Caller->use_empty()) { |
| Attributes RAttrs = CallerPAL.getRetAttributes(); |
| if (RAttrs & Attribute::typeIncompatible(NewRetTy)) |
| return false; // Attribute not compatible with transformed value. |
| } |
| |
| // If the callsite is an invoke instruction, and the return value is used by |
| // a PHI node in a successor, we cannot change the return type of the call |
| // because there is no place to put the cast instruction (without breaking |
| // the critical edge). Bail out in this case. |
| if (!Caller->use_empty()) |
| if (InvokeInst *II = dyn_cast<InvokeInst>(Caller)) |
| for (Value::use_iterator UI = II->use_begin(), E = II->use_end(); |
| UI != E; ++UI) |
| if (PHINode *PN = dyn_cast<PHINode>(*UI)) |
| if (PN->getParent() == II->getNormalDest() || |
| PN->getParent() == II->getUnwindDest()) |
| return false; |
| } |
| |
| unsigned NumActualArgs = unsigned(CS.arg_end()-CS.arg_begin()); |
| unsigned NumCommonArgs = std::min(FT->getNumParams(), NumActualArgs); |
| |
| CallSite::arg_iterator AI = CS.arg_begin(); |
| for (unsigned i = 0, e = NumCommonArgs; i != e; ++i, ++AI) { |
| Type *ParamTy = FT->getParamType(i); |
| Type *ActTy = (*AI)->getType(); |
| |
| if (!CastInst::isCastable(ActTy, ParamTy)) |
| return false; // Cannot transform this parameter value. |
| |
| Attributes Attrs = CallerPAL.getParamAttributes(i + 1); |
| if (Attrs & Attribute::typeIncompatible(ParamTy)) |
| return false; // Attribute not compatible with transformed value. |
| |
| // If the parameter is passed as a byval argument, then we have to have a |
| // sized type and the sized type has to have the same size as the old type. |
| if (ParamTy != ActTy && (Attrs & Attribute::ByVal)) { |
| PointerType *ParamPTy = dyn_cast<PointerType>(ParamTy); |
| if (ParamPTy == 0 || !ParamPTy->getElementType()->isSized() || TD == 0) |
| return false; |
| |
| Type *CurElTy = cast<PointerType>(ActTy)->getElementType(); |
| if (TD->getTypeAllocSize(CurElTy) != |
| TD->getTypeAllocSize(ParamPTy->getElementType())) |
| return false; |
| } |
| |
| // Converting from one pointer type to another or between a pointer and an |
| // integer of the same size is safe even if we do not have a body. |
| bool isConvertible = ActTy == ParamTy || |
| (TD && ((ParamTy->isPointerTy() || |
| ParamTy == TD->getIntPtrType(Caller->getContext())) && |
| (ActTy->isPointerTy() || |
| ActTy == TD->getIntPtrType(Caller->getContext())))); |
| if (Callee->isDeclaration() && !isConvertible) return false; |
| } |
| |
| if (Callee->isDeclaration()) { |
| // Do not delete arguments unless we have a function body. |
| if (FT->getNumParams() < NumActualArgs && !FT->isVarArg()) |
| return false; |
| |
| // If the callee is just a declaration, don't change the varargsness of the |
| // call. We don't want to introduce a varargs call where one doesn't |
| // already exist. |
| PointerType *APTy = cast<PointerType>(CS.getCalledValue()->getType()); |
| if (FT->isVarArg()!=cast<FunctionType>(APTy->getElementType())->isVarArg()) |
| return false; |
| } |
| |
| if (FT->getNumParams() < NumActualArgs && FT->isVarArg() && |
| !CallerPAL.isEmpty()) |
| // In this case we have more arguments than the new function type, but we |
| // won't be dropping them. Check that these extra arguments have attributes |
| // that are compatible with being a vararg call argument. |
| for (unsigned i = CallerPAL.getNumSlots(); i; --i) { |
| if (CallerPAL.getSlot(i - 1).Index <= FT->getNumParams()) |
| break; |
| Attributes PAttrs = CallerPAL.getSlot(i - 1).Attrs; |
| if (PAttrs & Attribute::VarArgsIncompatible) |
| return false; |
| } |
| |
| |
| // Okay, we decided that this is a safe thing to do: go ahead and start |
| // inserting cast instructions as necessary. |
| std::vector<Value*> Args; |
| Args.reserve(NumActualArgs); |
| SmallVector<AttributeWithIndex, 8> attrVec; |
| attrVec.reserve(NumCommonArgs); |
| |
| // Get any return attributes. |
| Attributes RAttrs = CallerPAL.getRetAttributes(); |
| |
| // If the return value is not being used, the type may not be compatible |
| // with the existing attributes. Wipe out any problematic attributes. |
| RAttrs &= ~Attribute::typeIncompatible(NewRetTy); |
| |
| // Add the new return attributes. |
| if (RAttrs) |
| attrVec.push_back(AttributeWithIndex::get(0, RAttrs)); |
| |
| AI = CS.arg_begin(); |
| for (unsigned i = 0; i != NumCommonArgs; ++i, ++AI) { |
| Type *ParamTy = FT->getParamType(i); |
| if ((*AI)->getType() == ParamTy) { |
| Args.push_back(*AI); |
| } else { |
| Instruction::CastOps opcode = CastInst::getCastOpcode(*AI, |
| false, ParamTy, false); |
| Args.push_back(Builder->CreateCast(opcode, *AI, ParamTy)); |
| } |
| |
| // Add any parameter attributes. |
| if (Attributes PAttrs = CallerPAL.getParamAttributes(i + 1)) |
| attrVec.push_back(AttributeWithIndex::get(i + 1, PAttrs)); |
| } |
| |
| // If the function takes more arguments than the call was taking, add them |
| // now. |
| for (unsigned i = NumCommonArgs; i != FT->getNumParams(); ++i) |
| Args.push_back(Constant::getNullValue(FT->getParamType(i))); |
| |
| // If we are removing arguments to the function, emit an obnoxious warning. |
| if (FT->getNumParams() < NumActualArgs) { |
| if (!FT->isVarArg()) { |
| errs() << "WARNING: While resolving call to function '" |
| << Callee->getName() << "' arguments were dropped!\n"; |
| } else { |
| // Add all of the arguments in their promoted form to the arg list. |
| for (unsigned i = FT->getNumParams(); i != NumActualArgs; ++i, ++AI) { |
| Type *PTy = getPromotedType((*AI)->getType()); |
| if (PTy != (*AI)->getType()) { |
| // Must promote to pass through va_arg area! |
| Instruction::CastOps opcode = |
| CastInst::getCastOpcode(*AI, false, PTy, false); |
| Args.push_back(Builder->CreateCast(opcode, *AI, PTy)); |
| } else { |
| Args.push_back(*AI); |
| } |
| |
| // Add any parameter attributes. |
| if (Attributes PAttrs = CallerPAL.getParamAttributes(i + 1)) |
| attrVec.push_back(AttributeWithIndex::get(i + 1, PAttrs)); |
| } |
| } |
| } |
| |
| if (Attributes FnAttrs = CallerPAL.getFnAttributes()) |
| attrVec.push_back(AttributeWithIndex::get(~0, FnAttrs)); |
| |
| if (NewRetTy->isVoidTy()) |
| Caller->setName(""); // Void type should not have a name. |
| |
| const AttrListPtr &NewCallerPAL = AttrListPtr::get(attrVec.begin(), |
| attrVec.end()); |
| |
| Instruction *NC; |
| if (InvokeInst *II = dyn_cast<InvokeInst>(Caller)) { |
| NC = Builder->CreateInvoke(Callee, II->getNormalDest(), |
| II->getUnwindDest(), Args); |
| NC->takeName(II); |
| cast<InvokeInst>(NC)->setCallingConv(II->getCallingConv()); |
| cast<InvokeInst>(NC)->setAttributes(NewCallerPAL); |
| } else { |
| CallInst *CI = cast<CallInst>(Caller); |
| NC = Builder->CreateCall(Callee, Args); |
| NC->takeName(CI); |
| if (CI->isTailCall()) |
| cast<CallInst>(NC)->setTailCall(); |
| cast<CallInst>(NC)->setCallingConv(CI->getCallingConv()); |
| cast<CallInst>(NC)->setAttributes(NewCallerPAL); |
| } |
| |
| // Insert a cast of the return type as necessary. |
| Value *NV = NC; |
| if (OldRetTy != NV->getType() && !Caller->use_empty()) { |
| if (!NV->getType()->isVoidTy()) { |
| Instruction::CastOps opcode = |
| CastInst::getCastOpcode(NC, false, OldRetTy, false); |
| NV = NC = CastInst::Create(opcode, NC, OldRetTy); |
| NC->setDebugLoc(Caller->getDebugLoc()); |
| |
| // If this is an invoke instruction, we should insert it after the first |
| // non-phi, instruction in the normal successor block. |
| if (InvokeInst *II = dyn_cast<InvokeInst>(Caller)) { |
| BasicBlock::iterator I = II->getNormalDest()->getFirstInsertionPt(); |
| InsertNewInstBefore(NC, *I); |
| } else { |
| // Otherwise, it's a call, just insert cast right after the call. |
| InsertNewInstBefore(NC, *Caller); |
| } |
| Worklist.AddUsersToWorkList(*Caller); |
| } else { |
| NV = UndefValue::get(Caller->getType()); |
| } |
| } |
| |
| if (!Caller->use_empty()) |
| ReplaceInstUsesWith(*Caller, NV); |
| |
| EraseInstFromFunction(*Caller); |
| return true; |
| } |
| |
| // transformCallThroughTrampoline - Turn a call to a function created by |
| // init_trampoline / adjust_trampoline intrinsic pair into a direct call to the |
| // underlying function. |
| // |
| Instruction * |
| InstCombiner::transformCallThroughTrampoline(CallSite CS, |
| IntrinsicInst *Tramp) { |
| Value *Callee = CS.getCalledValue(); |
| PointerType *PTy = cast<PointerType>(Callee->getType()); |
| FunctionType *FTy = cast<FunctionType>(PTy->getElementType()); |
| const AttrListPtr &Attrs = CS.getAttributes(); |
| |
| // If the call already has the 'nest' attribute somewhere then give up - |
| // otherwise 'nest' would occur twice after splicing in the chain. |
| if (Attrs.hasAttrSomewhere(Attribute::Nest)) |
| return 0; |
| |
| assert(Tramp && |
| "transformCallThroughTrampoline called with incorrect CallSite."); |
| |
| Function *NestF =cast<Function>(Tramp->getArgOperand(1)->stripPointerCasts()); |
| PointerType *NestFPTy = cast<PointerType>(NestF->getType()); |
| FunctionType *NestFTy = cast<FunctionType>(NestFPTy->getElementType()); |
| |
| const AttrListPtr &NestAttrs = NestF->getAttributes(); |
| if (!NestAttrs.isEmpty()) { |
| unsigned NestIdx = 1; |
| Type *NestTy = 0; |
| Attributes NestAttr = Attribute::None; |
| |
| // Look for a parameter marked with the 'nest' attribute. |
| for (FunctionType::param_iterator I = NestFTy->param_begin(), |
| E = NestFTy->param_end(); I != E; ++NestIdx, ++I) |
| if (NestAttrs.paramHasAttr(NestIdx, Attribute::Nest)) { |
| // Record the parameter type and any other attributes. |
| NestTy = *I; |
| NestAttr = NestAttrs.getParamAttributes(NestIdx); |
| break; |
| } |
| |
| if (NestTy) { |
| Instruction *Caller = CS.getInstruction(); |
| std::vector<Value*> NewArgs; |
| NewArgs.reserve(unsigned(CS.arg_end()-CS.arg_begin())+1); |
| |
| SmallVector<AttributeWithIndex, 8> NewAttrs; |
| NewAttrs.reserve(Attrs.getNumSlots() + 1); |
| |
| // Insert the nest argument into the call argument list, which may |
| // mean appending it. Likewise for attributes. |
| |
| // Add any result attributes. |
| if (Attributes Attr = Attrs.getRetAttributes()) |
| NewAttrs.push_back(AttributeWithIndex::get(0, Attr)); |
| |
| { |
| unsigned Idx = 1; |
| CallSite::arg_iterator I = CS.arg_begin(), E = CS.arg_end(); |
| do { |
| if (Idx == NestIdx) { |
| // Add the chain argument and attributes. |
| Value *NestVal = Tramp->getArgOperand(2); |
| if (NestVal->getType() != NestTy) |
| NestVal = Builder->CreateBitCast(NestVal, NestTy, "nest"); |
| NewArgs.push_back(NestVal); |
| NewAttrs.push_back(AttributeWithIndex::get(NestIdx, NestAttr)); |
| } |
| |
| if (I == E) |
| break; |
| |
| // Add the original argument and attributes. |
| NewArgs.push_back(*I); |
| if (Attributes Attr = Attrs.getParamAttributes(Idx)) |
| NewAttrs.push_back |
| (AttributeWithIndex::get(Idx + (Idx >= NestIdx), Attr)); |
| |
| ++Idx, ++I; |
| } while (1); |
| } |
| |
| // Add any function attributes. |
| if (Attributes Attr = Attrs.getFnAttributes()) |
| NewAttrs.push_back(AttributeWithIndex::get(~0, Attr)); |
| |
| // The trampoline may have been bitcast to a bogus type (FTy). |
| // Handle this by synthesizing a new function type, equal to FTy |
| // with the chain parameter inserted. |
| |
| std::vector<Type*> NewTypes; |
| NewTypes.reserve(FTy->getNumParams()+1); |
| |
| // Insert the chain's type into the list of parameter types, which may |
| // mean appending it. |
| { |
| unsigned Idx = 1; |
| FunctionType::param_iterator I = FTy->param_begin(), |
| E = FTy->param_end(); |
| |
| do { |
| if (Idx == NestIdx) |
| // Add the chain's type. |
| NewTypes.push_back(NestTy); |
| |
| if (I == E) |
| break; |
| |
| // Add the original type. |
| NewTypes.push_back(*I); |
| |
| ++Idx, ++I; |
| } while (1); |
| } |
| |
| // Replace the trampoline call with a direct call. Let the generic |
| // code sort out any function type mismatches. |
| FunctionType *NewFTy = FunctionType::get(FTy->getReturnType(), NewTypes, |
| FTy->isVarArg()); |
| Constant *NewCallee = |
| NestF->getType() == PointerType::getUnqual(NewFTy) ? |
| NestF : ConstantExpr::getBitCast(NestF, |
| PointerType::getUnqual(NewFTy)); |
| const AttrListPtr &NewPAL = AttrListPtr::get(NewAttrs.begin(), |
| NewAttrs.end()); |
| |
| Instruction *NewCaller; |
| if (InvokeInst *II = dyn_cast<InvokeInst>(Caller)) { |
| NewCaller = InvokeInst::Create(NewCallee, |
| II->getNormalDest(), II->getUnwindDest(), |
| NewArgs); |
| cast<InvokeInst>(NewCaller)->setCallingConv(II->getCallingConv()); |
| cast<InvokeInst>(NewCaller)->setAttributes(NewPAL); |
| } else { |
| NewCaller = CallInst::Create(NewCallee, NewArgs); |
| if (cast<CallInst>(Caller)->isTailCall()) |
| cast<CallInst>(NewCaller)->setTailCall(); |
| cast<CallInst>(NewCaller)-> |
| setCallingConv(cast<CallInst>(Caller)->getCallingConv()); |
| cast<CallInst>(NewCaller)->setAttributes(NewPAL); |
| } |
| |
| return NewCaller; |
| } |
| } |
| |
| // Replace the trampoline call with a direct call. Since there is no 'nest' |
| // parameter, there is no need to adjust the argument list. Let the generic |
| // code sort out any function type mismatches. |
| Constant *NewCallee = |
| NestF->getType() == PTy ? NestF : |
| ConstantExpr::getBitCast(NestF, PTy); |
| CS.setCalledFunction(NewCallee); |
| return CS.getInstruction(); |
| } |