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