| //===- MCSectionELF.h - ELF 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 MCSectionELF class. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #ifndef LLVM_MC_MCSECTIONELF_H |
| #define LLVM_MC_MCSECTIONELF_H |
| |
| #include "llvm/ADT/PointerIntPair.h" |
| #include "llvm/ADT/StringRef.h" |
| #include "llvm/MC/MCSection.h" |
| #include "llvm/MC/MCSymbolELF.h" |
| #include "llvm/MC/SectionKind.h" |
| |
| namespace llvm { |
| |
| /// This represents a section on linux, lots of unix variants and some bare |
| /// metal systems. |
| class MCSectionELF final : public MCSection { |
| /// This is the sh_type field of a section, drawn from the enums below. |
| unsigned Type; |
| |
| /// This is the sh_flags field of a section, drawn from the enums below. |
| unsigned Flags; |
| |
| unsigned UniqueID; |
| |
| /// The size of each entry in this section. This size only makes sense for |
| /// sections that contain fixed-sized entries. If a section does not contain |
| /// fixed-sized entries 'EntrySize' will be 0. |
| unsigned EntrySize; |
| |
| /// The section group signature symbol (if not null) and a bool indicating |
| /// whether this is a GRP_COMDAT group. |
| const PointerIntPair<const MCSymbolELF *, 1, bool> Group; |
| |
| /// Used by SHF_LINK_ORDER. If non-null, the sh_link field will be set to the |
| /// section header index of the section where LinkedToSym is defined. |
| const MCSymbol *LinkedToSym; |
| |
| private: |
| friend class MCContext; |
| |
| // The storage of Name is owned by MCContext's ELFUniquingMap. |
| MCSectionELF(StringRef Name, unsigned type, unsigned flags, SectionKind K, |
| unsigned entrySize, const MCSymbolELF *group, bool IsComdat, |
| unsigned UniqueID, MCSymbol *Begin, |
| const MCSymbolELF *LinkedToSym) |
| : MCSection(SV_ELF, Name, K, Begin), Type(type), Flags(flags), |
| UniqueID(UniqueID), EntrySize(entrySize), Group(group, IsComdat), |
| LinkedToSym(LinkedToSym) { |
| if (Group.getPointer()) |
| Group.getPointer()->setIsSignature(); |
| } |
| |
| // TODO Delete after we stop supporting generation of GNU-style .zdebug_* |
| // sections. |
| void setSectionName(StringRef Name) { this->Name = Name; } |
| |
| public: |
| /// Decides whether a '.section' directive should be printed before the |
| /// section name |
| bool shouldOmitSectionDirective(StringRef Name, const MCAsmInfo &MAI) const; |
| |
| unsigned getType() const { return Type; } |
| unsigned getFlags() const { return Flags; } |
| unsigned getEntrySize() const { return EntrySize; } |
| void setFlags(unsigned F) { Flags = F; } |
| const MCSymbolELF *getGroup() const { return Group.getPointer(); } |
| bool isComdat() const { return Group.getInt(); } |
| |
| 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 getVirtualSectionKind() const override; |
| |
| bool isUnique() const { return UniqueID != NonUniqueID; } |
| unsigned getUniqueID() const { return UniqueID; } |
| |
| const MCSection *getLinkedToSection() const { |
| return &LinkedToSym->getSection(); |
| } |
| const MCSymbol *getLinkedToSymbol() const { return LinkedToSym; } |
| |
| static bool classof(const MCSection *S) { |
| return S->getVariant() == SV_ELF; |
| } |
| }; |
| |
| } // end namespace llvm |
| |
| #endif // LLVM_MC_MCSECTIONELF_H |