llvm/lib/VMCore/IntrinsicLowering.cpp
Chris Lattner 2751e76a70 Add support for the llvm.memmove intrinsic
Patch graciously contributed by Reid Spencer!


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11355 91177308-0d34-0410-b5e6-96231b3b80d8
2004-02-12 18:11:20 +00:00

93 lines
3.4 KiB
C++

//===-- 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/IntrinsicLowering.h"
#include "llvm/Constant.h"
#include "llvm/DerivedTypes.h"
#include "llvm/Module.h"
#include "llvm/iOther.h"
using namespace llvm;
void DefaultIntrinsicLowering::LowerIntrinsicCall(CallInst *CI) {
Function *Callee = CI->getCalledFunction();
assert(Callee && "Cannot lower an indirect call!");
Module *M = Callee->getParent();
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 default implementation of setjmp/longjmp transforms setjmp into a
// noop that always returns zero and longjmp into a call to abort. This
// allows code that never longjmps to work correctly.
case Intrinsic::setjmp:
case Intrinsic::sigsetjmp:
if (CI->getType() != Type::VoidTy)
CI->replaceAllUsesWith(Constant::getNullValue(CI->getType()));
break;
case Intrinsic::longjmp:
case Intrinsic::siglongjmp:
// Insert the call to abort
new CallInst(M->getOrInsertFunction("abort", Type::VoidTy, 0), "", CI);
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.
const FunctionType *CFT = Callee->getFunctionType();
FunctionType *FT =
FunctionType::get(*CFT->param_begin(),
std::vector<const Type*>(CFT->param_begin(), CFT->param_end()-1),
false);
Function *MemCpy = M->getOrInsertFunction("memcpy", FT);
new CallInst(MemCpy, std::vector<Value*>(CI->op_begin()+1, CI->op_end()-1),
CI->getName(), CI);
break;
}
case Intrinsic::memmove: {
// The memmove intrinsic take an extra alignment argument that the memcpy
// libc function does not.
const FunctionType *CFT = Callee->getFunctionType();
FunctionType *FT =
FunctionType::get(*CFT->param_begin(),
std::vector<const Type*>(CFT->param_begin(), CFT->param_end()-1),
false);
Function *MemMove = M->getOrInsertFunction("memmove", FT);
new CallInst(MemMove, std::vector<Value*>(CI->op_begin()+1, CI->op_end()-1),
CI->getName(), CI);
break;
}
}
assert(CI->use_empty() &&
"Lowering should have eliminated any uses of the intrinsic call!");
CI->getParent()->getInstList().erase(CI);
}