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Diffstat (limited to 'contrib/llvm/lib/Transforms/InstCombine/InstCombineCalls.cpp')
| -rw-r--r-- | contrib/llvm/lib/Transforms/InstCombine/InstCombineCalls.cpp | 1381 |
1 files changed, 1381 insertions, 0 deletions
diff --git a/contrib/llvm/lib/Transforms/InstCombine/InstCombineCalls.cpp b/contrib/llvm/lib/Transforms/InstCombine/InstCombineCalls.cpp new file mode 100644 index 0000000..cbe1ca4 --- /dev/null +++ b/contrib/llvm/lib/Transforms/InstCombine/InstCombineCalls.cpp @@ -0,0 +1,1381 @@ +//===- 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. + uint64_t Size = MemOpLength->getLimitedValue(); + assert(Size && "0-sized memory transfering should be removed already."); + + 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->getLimitedValue(); + Alignment = MI->getAlignment(); + assert(Len && "0-sized memory setting should be removed already."); + + // 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 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: { + uint64_t Size; + if (getObjectSize(II->getArgOperand(0), Size, TD)) + return ReplaceInstUsesWith(CI, ConstantInt::get(CI.getType(), Size)); + return 0; + } + 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), 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), 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 LHSKnownZero(BitWidth, 0); + APInt LHSKnownOne(BitWidth, 0); + ComputeMaskedBits(LHS, 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, 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 LHSKnownZero(BitWidth, 0); + APInt LHSKnownOne(BitWidth, 0); + ComputeMaskedBits(LHS, LHSKnownZero, LHSKnownOne); + APInt RHSKnownZero(BitWidth, 0); + APInt RHSKnownOne(BitWidth, 0); + ComputeMaskedBits(RHS, 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::arm_neon_vmulls: + case Intrinsic::arm_neon_vmullu: { + Value *Arg0 = II->getArgOperand(0); + Value *Arg1 = II->getArgOperand(1); + + // Handle mul by zero first: + if (isa<ConstantAggregateZero>(Arg0) || isa<ConstantAggregateZero>(Arg1)) { + return ReplaceInstUsesWith(CI, ConstantAggregateZero::get(II->getType())); + } + + // Check for constant LHS & RHS - in this case we just simplify. + bool Zext = (II->getIntrinsicID() == Intrinsic::arm_neon_vmullu); + VectorType *NewVT = cast<VectorType>(II->getType()); + unsigned NewWidth = NewVT->getElementType()->getIntegerBitWidth(); + if (ConstantDataVector *CV0 = dyn_cast<ConstantDataVector>(Arg0)) { + if (ConstantDataVector *CV1 = dyn_cast<ConstantDataVector>(Arg1)) { + VectorType* VT = cast<VectorType>(CV0->getType()); + SmallVector<Constant*, 4> NewElems; + for (unsigned i = 0; i < VT->getNumElements(); ++i) { + APInt CV0E = + (cast<ConstantInt>(CV0->getAggregateElement(i)))->getValue(); + CV0E = Zext ? CV0E.zext(NewWidth) : CV0E.sext(NewWidth); + APInt CV1E = + (cast<ConstantInt>(CV1->getAggregateElement(i)))->getValue(); + CV1E = Zext ? CV1E.zext(NewWidth) : CV1E.sext(NewWidth); + NewElems.push_back( + ConstantInt::get(NewVT->getElementType(), CV0E * CV1E)); + } + return ReplaceInstUsesWith(CI, ConstantVector::get(NewElems)); + } + + // Couldn't simplify - cannonicalize constant to the RHS. + std::swap(Arg0, Arg1); + } + + // Handle mul by one: + if (ConstantDataVector *CV1 = dyn_cast<ConstantDataVector>(Arg1)) { + if (ConstantInt *Splat = + dyn_cast_or_null<ConstantInt>(CV1->getSplatValue())) { + if (Splat->isOne()) { + if (Zext) + return CastInst::CreateZExtOrBitCast(Arg0, II->getType()); + // else + return CastInst::CreateSExtOrBitCast(Arg0, II->getType()); + } + } + } + + 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)) { + 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))) + 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, TLI); + 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) { + if (isAllocLikeFn(CS.getInstruction())) + return visitAllocSite(*CS.getInstruction()); + + 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)) { + // 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 (isa<InvokeInst>(CS.getInstruction())) { + // Can't remove an invoke because we cannot change the CFG. + return 0; + } + + // 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()); + + 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 both the callee and the cast type are varargs, we still have to make + // sure the number of fixed parameters are the same or we have the same + // ABI issues as if we introduce a varargs call. + if (FT->isVarArg() && + cast<FunctionType>(APTy->getElementType())->isVarArg() && + FT->getNumParams() != + cast<FunctionType>(APTy->getElementType())->getNumParams()) + 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); + + 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); + + 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(); +} |
