llvm-for-llvmta/include/llvm/MC/MCSectionXCOFF.h

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//===- MCSectionXCOFF.h - XCOFF Machine Code Sections -----------*- 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 declares the MCSectionXCOFF class.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_MC_MCSECTIONXCOFF_H
#define LLVM_MC_MCSECTIONXCOFF_H
#include "llvm/BinaryFormat/XCOFF.h"
#include "llvm/MC/MCSection.h"
#include "llvm/MC/MCSymbolXCOFF.h"
namespace llvm {
// This class represents an XCOFF `Control Section`, more commonly referred to
// as a csect. A csect represents the smallest possible unit of data/code which
// will be relocated as a single block. A csect can either be:
// 1) Initialized: The Type will be XTY_SD, and the symbols inside the csect
// will have a label definition representing their offset within the csect.
// 2) Uninitialized: The Type will be XTY_CM, it will contain a single symbol,
// and may not contain label definitions.
// 3) An external reference providing a symbol table entry for a symbol
// contained in another XCOFF object file. External reference csects are not
// implemented yet.
class MCSectionXCOFF final : public MCSection {
friend class MCContext;
XCOFF::StorageMappingClass MappingClass;
XCOFF::SymbolType Type;
MCSymbolXCOFF *const QualName;
StringRef SymbolTableName;
bool MultiSymbolsAllowed;
static constexpr unsigned DefaultAlignVal = 4;
MCSectionXCOFF(StringRef Name, XCOFF::StorageMappingClass SMC,
XCOFF::SymbolType ST, SectionKind K, MCSymbolXCOFF *QualName,
MCSymbol *Begin, StringRef SymbolTableName,
bool MultiSymbolsAllowed)
: MCSection(SV_XCOFF, Name, K, Begin), MappingClass(SMC), Type(ST),
QualName(QualName), SymbolTableName(SymbolTableName),
MultiSymbolsAllowed(MultiSymbolsAllowed) {
assert((ST == XCOFF::XTY_SD || ST == XCOFF::XTY_CM || ST == XCOFF::XTY_ER) &&
"Invalid or unhandled type for csect.");
assert(QualName != nullptr && "QualName is needed.");
QualName->setRepresentedCsect(this);
QualName->setStorageClass(XCOFF::C_HIDEXT);
// A csect is 4 byte aligned by default, except for undefined symbol csects.
if (Type != XCOFF::XTY_ER)
setAlignment(Align(DefaultAlignVal));
}
void printCsectDirective(raw_ostream &OS) const;
public:
~MCSectionXCOFF();
static bool classof(const MCSection *S) {
return S->getVariant() == SV_XCOFF;
}
XCOFF::StorageMappingClass getMappingClass() const { return MappingClass; }
XCOFF::StorageClass getStorageClass() const {
return QualName->getStorageClass();
}
XCOFF::SymbolType getCSectType() const { return Type; }
MCSymbolXCOFF *getQualNameSymbol() const { return QualName; }
void PrintSwitchToSection(const MCAsmInfo &MAI, const Triple &T,
raw_ostream &OS,
const MCExpr *Subsection) const override;
bool UseCodeAlign() const override;
bool isVirtualSection() const override;
StringRef getSymbolTableName() const { return SymbolTableName; }
bool isMultiSymbolsAllowed() const { return MultiSymbolsAllowed; }
};
} // end namespace llvm
#endif