llvm-project/llvm/lib/Target/LoongArch/MCTargetDesc/LoongArchAsmBackend.cpp

69 lines
2.6 KiB
C++

//===-- LoongArchAsmBackend.cpp - LoongArch Assembler Backend -*- C++ -*---===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// This file implements the LoongArchAsmBackend class.
//
//===----------------------------------------------------------------------===//
#include "LoongArchAsmBackend.h"
#include "llvm/MC/MCAsmLayout.h"
#include "llvm/MC/MCAssembler.h"
#include "llvm/MC/MCContext.h"
#include "llvm/MC/MCELFObjectWriter.h"
#include "llvm/Support/Endian.h"
#include "llvm/Support/EndianStream.h"
#define DEBUG_TYPE "loongarch-asmbackend"
using namespace llvm;
void LoongArchAsmBackend::applyFixup(const MCAssembler &Asm,
const MCFixup &Fixup,
const MCValue &Target,
MutableArrayRef<char> Data, uint64_t Value,
bool IsResolved,
const MCSubtargetInfo *STI) const {
// TODO: Apply the Value for given Fixup into the provided data fragment.
return;
}
bool LoongArchAsmBackend::shouldForceRelocation(const MCAssembler &Asm,
const MCFixup &Fixup,
const MCValue &Target) {
// TODO: Determine which relocation require special processing at linking
// time.
return false;
}
bool LoongArchAsmBackend::writeNopData(raw_ostream &OS, uint64_t Count,
const MCSubtargetInfo *STI) const {
// Check for byte count not multiple of instruction word size
if (Count % 4 != 0)
return false;
// The nop on LoongArch is andi r0, r0, 0.
for (; Count >= 4; Count -= 4)
support::endian::write<uint32_t>(OS, 0x03400000, support::little);
return true;
}
std::unique_ptr<MCObjectTargetWriter>
LoongArchAsmBackend::createObjectTargetWriter() const {
return createLoongArchELFObjectWriter(OSABI, Is64Bit);
}
MCAsmBackend *llvm::createLoongArchAsmBackend(const Target &T,
const MCSubtargetInfo &STI,
const MCRegisterInfo &MRI,
const MCTargetOptions &Options) {
const Triple &TT = STI.getTargetTriple();
uint8_t OSABI = MCELFObjectTargetWriter::getOSABI(TT.getOS());
return new LoongArchAsmBackend(STI, OSABI, TT.isArch64Bit());
}