llvm-project/llvm/lib/MC/MCSectionCOFF.cpp

116 lines
3.5 KiB
C++

//===- lib/MC/MCSectionCOFF.cpp - COFF Code Section Representation --------===//
//
// 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/MCSectionCOFF.h"
#include "llvm/BinaryFormat/COFF.h"
#include "llvm/MC/MCSymbol.h"
#include "llvm/Support/raw_ostream.h"
#include <cassert>
using namespace llvm;
// shouldOmitSectionDirective - Decides whether a '.section' directive
// should be printed before the section name
bool MCSectionCOFF::shouldOmitSectionDirective(StringRef Name,
const MCAsmInfo &MAI) const {
if (COMDATSymbol)
return false;
// FIXME: Does .section .bss/.data/.text work everywhere??
if (Name == ".text" || Name == ".data" || Name == ".bss")
return true;
return false;
}
void MCSectionCOFF::setSelection(int Selection) const {
assert(Selection != 0 && "invalid COMDAT selection type");
this->Selection = Selection;
Characteristics |= COFF::IMAGE_SCN_LNK_COMDAT;
}
void MCSectionCOFF::printSwitchToSection(const MCAsmInfo &MAI, const Triple &T,
raw_ostream &OS,
const MCExpr *Subsection) const {
// standard sections don't require the '.section'
if (shouldOmitSectionDirective(getName(), MAI)) {
OS << '\t' << getName() << '\n';
return;
}
OS << "\t.section\t" << getName() << ",\"";
if (getCharacteristics() & COFF::IMAGE_SCN_CNT_INITIALIZED_DATA)
OS << 'd';
if (getCharacteristics() & COFF::IMAGE_SCN_CNT_UNINITIALIZED_DATA)
OS << 'b';
if (getCharacteristics() & COFF::IMAGE_SCN_MEM_EXECUTE)
OS << 'x';
if (getCharacteristics() & COFF::IMAGE_SCN_MEM_WRITE)
OS << 'w';
else if (getCharacteristics() & COFF::IMAGE_SCN_MEM_READ)
OS << 'r';
else
OS << 'y';
if (getCharacteristics() & COFF::IMAGE_SCN_LNK_REMOVE)
OS << 'n';
if (getCharacteristics() & COFF::IMAGE_SCN_MEM_SHARED)
OS << 's';
if ((getCharacteristics() & COFF::IMAGE_SCN_MEM_DISCARDABLE) &&
!isImplicitlyDiscardable(getName()))
OS << 'D';
OS << '"';
if (getCharacteristics() & COFF::IMAGE_SCN_LNK_COMDAT) {
if (COMDATSymbol)
OS << ",";
else
OS << "\n\t.linkonce\t";
switch (Selection) {
case COFF::IMAGE_COMDAT_SELECT_NODUPLICATES:
OS << "one_only";
break;
case COFF::IMAGE_COMDAT_SELECT_ANY:
OS << "discard";
break;
case COFF::IMAGE_COMDAT_SELECT_SAME_SIZE:
OS << "same_size";
break;
case COFF::IMAGE_COMDAT_SELECT_EXACT_MATCH:
OS << "same_contents";
break;
case COFF::IMAGE_COMDAT_SELECT_ASSOCIATIVE:
OS << "associative";
break;
case COFF::IMAGE_COMDAT_SELECT_LARGEST:
OS << "largest";
break;
case COFF::IMAGE_COMDAT_SELECT_NEWEST:
OS << "newest";
break;
default:
assert(false && "unsupported COFF selection type");
break;
}
if (COMDATSymbol) {
OS << ",";
COMDATSymbol->print(OS, &MAI);
}
}
OS << '\n';
}
bool MCSectionCOFF::useCodeAlign() const { return getKind().isText(); }
bool MCSectionCOFF::isVirtualSection() const {
return getCharacteristics() & COFF::IMAGE_SCN_CNT_UNINITIALIZED_DATA;
}
StringRef MCSectionCOFF::getVirtualSectionKind() const {
return "IMAGE_SCN_CNT_UNINITIALIZED_DATA";
}