| //===-- IntrinsicLowering.cpp - Intrinsic Lowering default implementation -===// |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file was developed by the LLVM research group and is distributed under |
| // the University of Illinois Open Source License. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // This file implements the default intrinsic lowering implementation. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "llvm/CodeGen/IntrinsicLowering.h" |
| #include "llvm/Constants.h" |
| #include "llvm/DerivedTypes.h" |
| #include "llvm/Module.h" |
| #include "llvm/Instructions.h" |
| #include <iostream> |
| |
| using namespace llvm; |
| |
| template <class ArgIt> |
| static Function *EnsureFunctionExists(Module &M, const char *Name, |
| ArgIt ArgBegin, ArgIt ArgEnd, |
| const Type *RetTy) { |
| if (Function *F = M.getNamedFunction(Name)) return F; |
| // It doesn't already exist in the program, insert a new definition now. |
| std::vector<const Type *> ParamTys; |
| for (ArgIt I = ArgBegin; I != ArgEnd; ++I) |
| ParamTys.push_back(I->getType()); |
| return M.getOrInsertFunction(Name, FunctionType::get(RetTy, ParamTys, false)); |
| } |
| |
| /// ReplaceCallWith - This function is used when we want to lower an intrinsic |
| /// call to a call of an external function. This handles hard cases such as |
| /// when there was already a prototype for the external function, and if that |
| /// prototype doesn't match the arguments we expect to pass in. |
| template <class ArgIt> |
| static CallInst *ReplaceCallWith(const char *NewFn, CallInst *CI, |
| ArgIt ArgBegin, ArgIt ArgEnd, |
| const Type *RetTy, Function *&FCache) { |
| if (!FCache) { |
| // If we haven't already looked up this function, check to see if the |
| // program already contains a function with this name. |
| Module *M = CI->getParent()->getParent()->getParent(); |
| FCache = M->getNamedFunction(NewFn); |
| if (!FCache) { |
| // It doesn't already exist in the program, insert a new definition now. |
| std::vector<const Type *> ParamTys; |
| for (ArgIt I = ArgBegin; I != ArgEnd; ++I) |
| ParamTys.push_back((*I)->getType()); |
| FCache = M->getOrInsertFunction(NewFn, |
| FunctionType::get(RetTy, ParamTys, false)); |
| } |
| } |
| |
| const FunctionType *FT = FCache->getFunctionType(); |
| std::vector<Value*> Operands; |
| unsigned ArgNo = 0; |
| for (ArgIt I = ArgBegin; I != ArgEnd && ArgNo != FT->getNumParams(); |
| ++I, ++ArgNo) { |
| Value *Arg = *I; |
| if (Arg->getType() != FT->getParamType(ArgNo)) |
| Arg = new CastInst(Arg, FT->getParamType(ArgNo), Arg->getName(), CI); |
| Operands.push_back(Arg); |
| } |
| // Pass nulls into any additional arguments... |
| for (; ArgNo != FT->getNumParams(); ++ArgNo) |
| Operands.push_back(Constant::getNullValue(FT->getParamType(ArgNo))); |
| |
| std::string Name = CI->getName(); CI->setName(""); |
| if (FT->getReturnType() == Type::VoidTy) Name.clear(); |
| CallInst *NewCI = new CallInst(FCache, Operands, Name, CI); |
| if (!CI->use_empty()) { |
| Value *V = NewCI; |
| if (CI->getType() != NewCI->getType()) |
| V = new CastInst(NewCI, CI->getType(), Name, CI); |
| CI->replaceAllUsesWith(V); |
| } |
| return NewCI; |
| } |
| |
| void DefaultIntrinsicLowering::AddPrototypes(Module &M) { |
| for (Module::iterator I = M.begin(), E = M.end(); I != E; ++I) |
| if (I->isExternal() && !I->use_empty()) |
| switch (I->getIntrinsicID()) { |
| default: break; |
| case Intrinsic::setjmp: |
| EnsureFunctionExists(M, "setjmp", I->abegin(), I->aend(), Type::IntTy); |
| break; |
| case Intrinsic::longjmp: |
| EnsureFunctionExists(M, "longjmp", I->abegin(), I->aend(),Type::VoidTy); |
| break; |
| case Intrinsic::siglongjmp: |
| EnsureFunctionExists(M, "abort", I->aend(), I->aend(), Type::VoidTy); |
| break; |
| case Intrinsic::memcpy: |
| EnsureFunctionExists(M, "memcpy", I->abegin(), --I->aend(), |
| I->abegin()->getType()); |
| break; |
| case Intrinsic::memmove: |
| EnsureFunctionExists(M, "memmove", I->abegin(), --I->aend(), |
| I->abegin()->getType()); |
| break; |
| case Intrinsic::memset: |
| EnsureFunctionExists(M, "memset", I->abegin(), --I->aend(), |
| I->abegin()->getType()); |
| break; |
| case Intrinsic::isunordered: |
| EnsureFunctionExists(M, "isunordered", I->abegin(), I->aend(), Type::BoolTy); |
| break; |
| } |
| |
| } |
| |
| void DefaultIntrinsicLowering::LowerIntrinsicCall(CallInst *CI) { |
| Function *Callee = CI->getCalledFunction(); |
| assert(Callee && "Cannot lower an indirect call!"); |
| |
| switch (Callee->getIntrinsicID()) { |
| case Intrinsic::not_intrinsic: |
| std::cerr << "Cannot lower a call to a non-intrinsic function '" |
| << Callee->getName() << "'!\n"; |
| abort(); |
| default: |
| std::cerr << "Error: Code generator does not support intrinsic function '" |
| << Callee->getName() << "'!\n"; |
| abort(); |
| |
| // The setjmp/longjmp intrinsics should only exist in the code if it was |
| // never optimized (ie, right out of the CFE), or if it has been hacked on |
| // by the lowerinvoke pass. In both cases, the right thing to do is to |
| // convert the call to an explicit setjmp or longjmp call. |
| case Intrinsic::setjmp: { |
| static Function *SetjmpFCache = 0; |
| Value *V = ReplaceCallWith("setjmp", CI, CI->op_begin()+1, CI->op_end(), |
| Type::IntTy, SetjmpFCache); |
| if (CI->getType() != Type::VoidTy) |
| CI->replaceAllUsesWith(V); |
| break; |
| } |
| case Intrinsic::sigsetjmp: |
| if (CI->getType() != Type::VoidTy) |
| CI->replaceAllUsesWith(Constant::getNullValue(CI->getType())); |
| break; |
| |
| case Intrinsic::longjmp: { |
| static Function *LongjmpFCache = 0; |
| ReplaceCallWith("longjmp", CI, CI->op_begin()+1, CI->op_end(), |
| Type::VoidTy, LongjmpFCache); |
| break; |
| } |
| |
| case Intrinsic::siglongjmp: { |
| // Insert the call to abort |
| static Function *AbortFCache = 0; |
| ReplaceCallWith("abort", CI, CI->op_end(), CI->op_end(), Type::VoidTy, |
| AbortFCache); |
| break; |
| } |
| |
| case Intrinsic::returnaddress: |
| case Intrinsic::frameaddress: |
| std::cerr << "WARNING: this target does not support the llvm." |
| << (Callee->getIntrinsicID() == Intrinsic::returnaddress ? |
| "return" : "frame") << "address intrinsic.\n"; |
| CI->replaceAllUsesWith(ConstantPointerNull::get( |
| cast<PointerType>(CI->getType()))); |
| break; |
| |
| case Intrinsic::dbg_stoppoint: |
| case Intrinsic::dbg_region_start: |
| case Intrinsic::dbg_region_end: |
| case Intrinsic::dbg_declare: |
| case Intrinsic::dbg_func_start: |
| if (CI->getType() != Type::VoidTy) |
| CI->replaceAllUsesWith(Constant::getNullValue(CI->getType())); |
| break; // Simply strip out debugging intrinsics |
| |
| case Intrinsic::memcpy: { |
| // The memcpy intrinsic take an extra alignment argument that the memcpy |
| // libc function does not. |
| static Function *MemcpyFCache = 0; |
| ReplaceCallWith("memcpy", CI, CI->op_begin()+1, CI->op_end()-1, |
| (*(CI->op_begin()+1))->getType(), MemcpyFCache); |
| break; |
| } |
| case Intrinsic::memmove: { |
| // The memmove intrinsic take an extra alignment argument that the memmove |
| // libc function does not. |
| static Function *MemmoveFCache = 0; |
| ReplaceCallWith("memmove", CI, CI->op_begin()+1, CI->op_end()-1, |
| (*(CI->op_begin()+1))->getType(), MemmoveFCache); |
| break; |
| } |
| case Intrinsic::memset: { |
| // The memset intrinsic take an extra alignment argument that the memset |
| // libc function does not. |
| static Function *MemsetFCache = 0; |
| ReplaceCallWith("memset", CI, CI->op_begin()+1, CI->op_end()-1, |
| (*(CI->op_begin()+1))->getType(), MemsetFCache); |
| break; |
| } |
| case Intrinsic::isunordered: { |
| static Function *isunorderedFCache = 0; |
| ReplaceCallWith("isunordered", CI, CI->op_begin()+1, CI->op_end(), |
| Type::BoolTy, isunorderedFCache); |
| break; |
| } |
| } |
| |
| assert(CI->use_empty() && |
| "Lowering should have eliminated any uses of the intrinsic call!"); |
| CI->getParent()->getInstList().erase(CI); |
| } |
