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//===-- lib/CodeGen/ELFCodeEmitter.cpp ------------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#include "ELFCodeEmitter.h"
#include "llvm/Constants.h"
#include "llvm/DerivedTypes.h"
#include "llvm/Function.h"
#include "llvm/CodeGen/MachineConstantPool.h"
#include "llvm/CodeGen/MachineJumpTableInfo.h"
#include "llvm/Target/TargetAsmInfo.h"
#include "llvm/Target/TargetData.h"
#include "llvm/Target/TargetMachine.h"
#include "llvm/Support/Mangler.h"
#include "llvm/Support/OutputBuffer.h"
//===----------------------------------------------------------------------===//
// ELFCodeEmitter Implementation
//===----------------------------------------------------------------------===//
namespace llvm {
/// startFunction - This callback is invoked when a new machine function is
/// about to be emitted.
void ELFCodeEmitter::startFunction(MachineFunction &F) {
// Align the output buffer to the appropriate alignment.
unsigned Align = 16; // FIXME: GENERICIZE!!
// Get the ELF Section that this function belongs in.
ES = &EW.getSection(".text", ELFWriter::ELFSection::SHT_PROGBITS,
ELFWriter::ELFSection::SHF_EXECINSTR |
ELFWriter::ELFSection::SHF_ALLOC);
OutBuffer = &ES->SectionData;
cerr << "FIXME: This code needs to be updated for changes in the "
<< "CodeEmitter interfaces. In particular, this should set "
<< "BufferBegin/BufferEnd/CurBufferPtr, not deal with OutBuffer!";
abort();
// Upgrade the section alignment if required.
if (ES->Align < Align) ES->Align = Align;
// Add padding zeros to the end of the buffer to make sure that the
// function will start on the correct byte alignment within the section.
OutputBuffer OB(*OutBuffer,
TM.getTargetData()->getPointerSizeInBits() == 64,
TM.getTargetData()->isLittleEndian());
OB.align(Align);
FnStart = OutBuffer->size();
}
/// finishFunction - This callback is invoked after the function is completely
/// finished.
bool ELFCodeEmitter::finishFunction(MachineFunction &F) {
// We now know the size of the function, add a symbol to represent it.
ELFWriter::ELFSym FnSym(F.getFunction());
// Figure out the binding (linkage) of the symbol.
switch (F.getFunction()->getLinkage()) {
default:
// appending linkage is illegal for functions.
assert(0 && "Unknown linkage type!");
case GlobalValue::ExternalLinkage:
FnSym.SetBind(ELFWriter::ELFSym::STB_GLOBAL);
break;
case GlobalValue::LinkOnceAnyLinkage:
case GlobalValue::LinkOnceODRLinkage:
case GlobalValue::WeakAnyLinkage:
case GlobalValue::WeakODRLinkage:
FnSym.SetBind(ELFWriter::ELFSym::STB_WEAK);
break;
case GlobalValue::PrivateLinkage:
assert (0 && "PrivateLinkage should not be in the symbol table.");
case GlobalValue::InternalLinkage:
FnSym.SetBind(ELFWriter::ELFSym::STB_LOCAL);
break;
}
ES->Size = OutBuffer->size();
FnSym.SetType(ELFWriter::ELFSym::STT_FUNC);
FnSym.SectionIdx = ES->SectionIdx;
FnSym.Value = FnStart; // Value = Offset from start of Section.
FnSym.Size = OutBuffer->size()-FnStart;
// Finally, add it to the symtab.
EW.SymbolTable.push_back(FnSym);
return false;
}
} // end namespace llvm