llvm-mirror/lib/MC/MCAsmBackend.cpp
Chandler Carruth ae65e281f3 Update the file headers across all of the LLVM projects in the monorepo
to reflect the new license.

We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.

Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.

llvm-svn: 351636
2019-01-19 08:50:56 +00:00

130 lines
4.5 KiB
C++

//===- MCAsmBackend.cpp - Target MC Assembly Backend ----------------------===//
//
// 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
//
//===----------------------------------------------------------------------===//
#include "llvm/MC/MCAsmBackend.h"
#include "llvm/ADT/None.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/MC/MCCodePadder.h"
#include "llvm/MC/MCELFObjectWriter.h"
#include "llvm/MC/MCFixupKindInfo.h"
#include "llvm/MC/MCMachObjectWriter.h"
#include "llvm/MC/MCObjectWriter.h"
#include "llvm/MC/MCWasmObjectWriter.h"
#include "llvm/MC/MCWinCOFFObjectWriter.h"
#include <cassert>
#include <cstddef>
#include <cstdint>
using namespace llvm;
MCAsmBackend::MCAsmBackend(support::endianness Endian)
: CodePadder(new MCCodePadder()), Endian(Endian) {}
MCAsmBackend::~MCAsmBackend() = default;
std::unique_ptr<MCObjectWriter>
MCAsmBackend::createObjectWriter(raw_pwrite_stream &OS) const {
auto TW = createObjectTargetWriter();
switch (TW->getFormat()) {
case Triple::ELF:
return createELFObjectWriter(cast<MCELFObjectTargetWriter>(std::move(TW)), OS,
Endian == support::little);
case Triple::MachO:
return createMachObjectWriter(cast<MCMachObjectTargetWriter>(std::move(TW)),
OS, Endian == support::little);
case Triple::COFF:
return createWinCOFFObjectWriter(
cast<MCWinCOFFObjectTargetWriter>(std::move(TW)), OS);
case Triple::Wasm:
return createWasmObjectWriter(cast<MCWasmObjectTargetWriter>(std::move(TW)),
OS);
default:
llvm_unreachable("unexpected object format");
}
}
std::unique_ptr<MCObjectWriter>
MCAsmBackend::createDwoObjectWriter(raw_pwrite_stream &OS,
raw_pwrite_stream &DwoOS) const {
auto TW = createObjectTargetWriter();
if (TW->getFormat() != Triple::ELF)
report_fatal_error("dwo only supported with ELF");
return createELFDwoObjectWriter(cast<MCELFObjectTargetWriter>(std::move(TW)),
OS, DwoOS, Endian == support::little);
}
Optional<MCFixupKind> MCAsmBackend::getFixupKind(StringRef Name) const {
return None;
}
const MCFixupKindInfo &MCAsmBackend::getFixupKindInfo(MCFixupKind Kind) const {
static const MCFixupKindInfo Builtins[] = {
{"FK_Data_1", 0, 8, 0},
{"FK_Data_2", 0, 16, 0},
{"FK_Data_4", 0, 32, 0},
{"FK_Data_8", 0, 64, 0},
{"FK_PCRel_1", 0, 8, MCFixupKindInfo::FKF_IsPCRel},
{"FK_PCRel_2", 0, 16, MCFixupKindInfo::FKF_IsPCRel},
{"FK_PCRel_4", 0, 32, MCFixupKindInfo::FKF_IsPCRel},
{"FK_PCRel_8", 0, 64, MCFixupKindInfo::FKF_IsPCRel},
{"FK_GPRel_1", 0, 8, 0},
{"FK_GPRel_2", 0, 16, 0},
{"FK_GPRel_4", 0, 32, 0},
{"FK_GPRel_8", 0, 64, 0},
{"FK_DTPRel_4", 0, 32, 0},
{"FK_DTPRel_8", 0, 64, 0},
{"FK_TPRel_4", 0, 32, 0},
{"FK_TPRel_8", 0, 64, 0},
{"FK_SecRel_1", 0, 8, 0},
{"FK_SecRel_2", 0, 16, 0},
{"FK_SecRel_4", 0, 32, 0},
{"FK_SecRel_8", 0, 64, 0},
{"FK_Data_Add_1", 0, 8, 0},
{"FK_Data_Add_2", 0, 16, 0},
{"FK_Data_Add_4", 0, 32, 0},
{"FK_Data_Add_8", 0, 64, 0},
{"FK_Data_Sub_1", 0, 8, 0},
{"FK_Data_Sub_2", 0, 16, 0},
{"FK_Data_Sub_4", 0, 32, 0},
{"FK_Data_Sub_8", 0, 64, 0}};
assert((size_t)Kind <= array_lengthof(Builtins) && "Unknown fixup kind");
return Builtins[Kind];
}
bool MCAsmBackend::fixupNeedsRelaxationAdvanced(
const MCFixup &Fixup, bool Resolved, uint64_t Value,
const MCRelaxableFragment *DF, const MCAsmLayout &Layout,
const bool WasForced) const {
if (!Resolved)
return true;
return fixupNeedsRelaxation(Fixup, Value, DF, Layout);
}
void MCAsmBackend::handleCodePaddingBasicBlockStart(
MCObjectStreamer *OS, const MCCodePaddingContext &Context) {
CodePadder->handleBasicBlockStart(OS, Context);
}
void MCAsmBackend::handleCodePaddingBasicBlockEnd(
const MCCodePaddingContext &Context) {
CodePadder->handleBasicBlockEnd(Context);
}
void MCAsmBackend::handleCodePaddingInstructionBegin(const MCInst &Inst) {
CodePadder->handleInstructionBegin(Inst);
}
void MCAsmBackend::handleCodePaddingInstructionEnd(const MCInst &Inst) {
CodePadder->handleInstructionEnd(Inst);
}
bool MCAsmBackend::relaxFragment(MCPaddingFragment *PF, MCAsmLayout &Layout) {
return CodePadder->relaxFragment(PF, Layout);
}