llvm-6502/lib/Target/ARM/ARMAsmBackend.cpp
Jim Grosbach a55661b6bd Enable MachO writing for ARM/Darwin. Lots of stuff still doesn't work
(relocations, e.g.), but this will allow simple things to flow through.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@118289 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-05 18:50:35 +00:00

160 lines
4.8 KiB
C++

//===-- ARMAsmBackend.cpp - ARM Assembler Backend -------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#include "llvm/Target/TargetAsmBackend.h"
#include "ARM.h"
//FIXME: add #include "ARMFixupKinds.h"
#include "llvm/ADT/Twine.h"
#include "llvm/MC/ELFObjectWriter.h"
#include "llvm/MC/MCAssembler.h"
#include "llvm/MC/MCExpr.h"
#include "llvm/MC/MCObjectFormat.h"
#include "llvm/MC/MCObjectWriter.h"
#include "llvm/MC/MCSectionELF.h"
#include "llvm/MC/MCSectionMachO.h"
#include "llvm/MC/MachObjectWriter.h"
#include "llvm/Support/ELF.h"
#include "llvm/Support/MachO.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Target/TargetRegistry.h"
#include "llvm/Target/TargetAsmBackend.h"
using namespace llvm;
namespace {
class ARMAsmBackend : public TargetAsmBackend {
public:
ARMAsmBackend(const Target &T)
: TargetAsmBackend(T) {
}
bool MayNeedRelaxation(const MCInst &Inst) const;
void RelaxInstruction(const MCInst &Inst, MCInst &Res) const;
bool WriteNopData(uint64_t Count, MCObjectWriter *OW) const;
unsigned getPointerSize() const {
return 4;
}
};
bool ARMAsmBackend::MayNeedRelaxation(const MCInst &Inst) const {
// FIXME: Thumb targets, different move constant targets..
return false;
}
void ARMAsmBackend::RelaxInstruction(const MCInst &Inst, MCInst &Res) const {
assert(0 && "ARMAsmBackend::RelaxInstruction() unimplemented");
return;
}
bool ARMAsmBackend::WriteNopData(uint64_t Count, MCObjectWriter *OW) const {
if ((Count % 4) != 0) {
// Fixme: % 2 for Thumb?
return false;
}
return true;
}
} // end anonymous namespace
namespace {
// FIXME: This should be in a separate file.
// ELF is an ELF of course...
class ELFARMAsmBackend : public ARMAsmBackend {
MCELFObjectFormat Format;
public:
Triple::OSType OSType;
ELFARMAsmBackend(const Target &T, Triple::OSType _OSType)
: ARMAsmBackend(T), OSType(_OSType) {
HasScatteredSymbols = true;
}
virtual const MCObjectFormat &getObjectFormat() const {
return Format;
}
void ApplyFixup(const MCFixup &Fixup, MCDataFragment &DF,
uint64_t Value) const;
bool isVirtualSection(const MCSection &Section) const {
const MCSectionELF &SE = static_cast<const MCSectionELF&>(Section);
return SE.getType() == MCSectionELF::SHT_NOBITS;
}
MCObjectWriter *createObjectWriter(raw_ostream &OS) const {
return new ELFObjectWriter(OS, /*Is64Bit=*/false,
OSType, ELF::EM_ARM,
/*IsLittleEndian=*/true,
/*HasRelocationAddend=*/false);
}
};
// Fixme: can we raise this to share code between Darwin and ELF?
void ELFARMAsmBackend::ApplyFixup(const MCFixup &Fixup, MCDataFragment &DF,
uint64_t Value) const {
assert(0 && "ELFARMAsmBackend::ApplyFixup() unimplemented");
}
// FIXME: This should be in a separate file.
class DarwinARMAsmBackend : public ARMAsmBackend {
MCMachOObjectFormat Format;
public:
DarwinARMAsmBackend(const Target &T)
: ARMAsmBackend(T) {
HasScatteredSymbols = true;
}
virtual const MCObjectFormat &getObjectFormat() const {
return Format;
}
void ApplyFixup(const MCFixup &Fixup, MCDataFragment &DF,
uint64_t Value) const;
bool isVirtualSection(const MCSection &Section) const {
const MCSectionMachO &SMO = static_cast<const MCSectionMachO&>(Section);
return (SMO.getType() == MCSectionMachO::S_ZEROFILL ||
SMO.getType() == MCSectionMachO::S_GB_ZEROFILL ||
SMO.getType() == MCSectionMachO::S_THREAD_LOCAL_ZEROFILL);
}
MCObjectWriter *createObjectWriter(raw_ostream &OS) const {
// FIXME: Subtarget info should be derived. Force v7 for now.
return new MachObjectWriter(OS, /*Is64Bit=*/false, MachO::CPUTypeARM,
MachO::CPUSubType_ARM_V7);
}
virtual bool doesSectionRequireSymbols(const MCSection &Section) const {
return false;
}
};
void DarwinARMAsmBackend::ApplyFixup(const MCFixup &Fixup, MCDataFragment &DF,
uint64_t Value) const {
assert(0 && "DarwinARMAsmBackend::ApplyFixup() unimplemented");
}
} // end anonymous namespace
TargetAsmBackend *llvm::createARMAsmBackend(const Target &T,
const std::string &TT) {
switch (Triple(TT).getOS()) {
case Triple::Darwin:
return new DarwinARMAsmBackend(T);
case Triple::MinGW32:
case Triple::Cygwin:
case Triple::Win32:
assert(0 && "Windows not supported on ARM");
default:
return new ELFARMAsmBackend(T, Triple(TT).getOS());
}
}