1//===- MCSectionELF.h - ELF Machine Code Sections ---------------*- C++ -*-===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file declares the MCSectionELF class. 11// 12//===----------------------------------------------------------------------===// 13 14#ifndef LLVM_MC_MCSECTIONELF_H 15#define LLVM_MC_MCSECTIONELF_H 16 17#include "llvm/ADT/Twine.h" 18#include "llvm/MC/MCSection.h" 19#include "llvm/MC/MCSymbol.h" 20#include "llvm/Support/Debug.h" 21#include "llvm/Support/ELF.h" 22#include "llvm/Support/raw_ostream.h" 23 24namespace llvm { 25 26class MCSymbol; 27 28/// MCSectionELF - This represents a section on linux, lots of unix variants 29/// and some bare metal systems. 30class MCSectionELF : public MCSection { 31 /// SectionName - This is the name of the section. The referenced memory is 32 /// owned by TargetLoweringObjectFileELF's ELFUniqueMap. 33 StringRef SectionName; 34 35 /// Type - This is the sh_type field of a section, drawn from the enums below. 36 unsigned Type; 37 38 /// Flags - This is the sh_flags field of a section, drawn from the enums. 39 /// below. 40 unsigned Flags; 41 42 unsigned UniqueID; 43 44 /// EntrySize - The size of each entry in this section. This size only 45 /// makes sense for sections that contain fixed-sized entries. If a 46 /// section does not contain fixed-sized entries 'EntrySize' will be 0. 47 unsigned EntrySize; 48 49 const MCSymbol *Group; 50 51 /// Depending on the type of the section this is sh_link or sh_info. 52 const MCSectionELF *Associated; 53 54private: 55 friend class MCContext; 56 MCSectionELF(StringRef Section, unsigned type, unsigned flags, SectionKind K, 57 unsigned entrySize, const MCSymbol *group, unsigned UniqueID, 58 MCSymbol *Begin, const MCSectionELF *Associated) 59 : MCSection(SV_ELF, K, Begin), SectionName(Section), Type(type), 60 Flags(flags), UniqueID(UniqueID), EntrySize(entrySize), Group(group), 61 Associated(Associated) {} 62 ~MCSectionELF() override; 63 64 void setSectionName(StringRef Name) { SectionName = Name; } 65 66public: 67 68 /// ShouldOmitSectionDirective - Decides whether a '.section' directive 69 /// should be printed before the section name 70 bool ShouldOmitSectionDirective(StringRef Name, const MCAsmInfo &MAI) const; 71 72 StringRef getSectionName() const { return SectionName; } 73 unsigned getType() const { return Type; } 74 unsigned getFlags() const { return Flags; } 75 unsigned getEntrySize() const { return EntrySize; } 76 const MCSymbol *getGroup() const { return Group; } 77 78 void PrintSwitchToSection(const MCAsmInfo &MAI, raw_ostream &OS, 79 const MCExpr *Subsection) const override; 80 bool UseCodeAlign() const override; 81 bool isVirtualSection() const override; 82 83 bool isUnique() const { return UniqueID != ~0U; } 84 unsigned getUniqueID() const { return UniqueID; } 85 86 const MCSectionELF *getAssociatedSection() const { return Associated; } 87 88 static bool classof(const MCSection *S) { 89 return S->getVariant() == SV_ELF; 90 } 91}; 92 93} // end namespace llvm 94 95#endif 96