1195098Sed//===- MCSection.h - Machine Code Sections ----------------------*- C++ -*-===//
2195098Sed//
3195098Sed//                     The LLVM Compiler Infrastructure
4195098Sed//
5195098Sed// This file is distributed under the University of Illinois Open Source
6195098Sed// License. See LICENSE.TXT for details.
7195098Sed//
8195098Sed//===----------------------------------------------------------------------===//
9195340Sed//
10195340Sed// This file declares the MCSection class.
11195340Sed//
12195340Sed//===----------------------------------------------------------------------===//
13195098Sed
14195098Sed#ifndef LLVM_MC_MCSECTION_H
15195098Sed#define LLVM_MC_MCSECTION_H
16195098Sed
17252723Sdim#include "llvm/ADT/StringRef.h"
18198090Srdivacky#include "llvm/MC/SectionKind.h"
19245431Sdim#include "llvm/Support/Compiler.h"
20195098Sed
21195098Sednamespace llvm {
22198090Srdivacky  class MCAsmInfo;
23252723Sdim  class MCExpr;
24198090Srdivacky  class raw_ostream;
25210299Sed
26195340Sed  /// MCSection - Instances of this class represent a uniqued identifier for a
27195340Sed  /// section in the current translation unit.  The MCContext class uniques and
28195340Sed  /// creates these.
29195098Sed  class MCSection {
30208599Srdivacky  public:
31208599Srdivacky    enum SectionVariant {
32208599Srdivacky      SV_COFF = 0,
33208599Srdivacky      SV_ELF,
34218893Sdim      SV_MachO
35208599Srdivacky    };
36208599Srdivacky
37208599Srdivacky  private:
38245431Sdim    MCSection(const MCSection&) LLVM_DELETED_FUNCTION;
39245431Sdim    void operator=(const MCSection&) LLVM_DELETED_FUNCTION;
40198090Srdivacky  protected:
41208599Srdivacky    MCSection(SectionVariant V, SectionKind K) : Variant(V), Kind(K) {}
42208599Srdivacky    SectionVariant Variant;
43198090Srdivacky    SectionKind Kind;
44195098Sed  public:
45198090Srdivacky    virtual ~MCSection();
46195098Sed
47198090Srdivacky    SectionKind getKind() const { return Kind; }
48208599Srdivacky
49208599Srdivacky    SectionVariant getVariant() const { return Variant; }
50210299Sed
51198090Srdivacky    virtual void PrintSwitchToSection(const MCAsmInfo &MAI,
52252723Sdim                                      raw_ostream &OS,
53252723Sdim                                      const MCExpr *Subsection) const = 0;
54206274Srdivacky
55252723Sdim    // Convenience routines to get label names for the beginning/end of a
56252723Sdim    // section.
57252723Sdim    virtual std::string getLabelBeginName() const = 0;
58252723Sdim    virtual std::string getLabelEndName() const = 0;
59252723Sdim
60206274Srdivacky    /// isBaseAddressKnownZero - Return true if we know that this section will
61206274Srdivacky    /// get a base address of zero.  In cases where we know that this is true we
62206274Srdivacky    /// can emit section offsets as direct references to avoid a subtraction
63206274Srdivacky    /// from the base of the section, saving a relocation.
64206274Srdivacky    virtual bool isBaseAddressKnownZero() const {
65206274Srdivacky      return false;
66206274Srdivacky    }
67198090Srdivacky
68218893Sdim    // UseCodeAlign - Return true if a .align directive should use
69218893Sdim    // "optimized nops" to fill instead of 0s.
70218893Sdim    virtual bool UseCodeAlign() const = 0;
71218893Sdim
72218893Sdim    /// isVirtualSection - Check whether this section is "virtual", that is
73218893Sdim    /// has no actual object file contents.
74218893Sdim    virtual bool isVirtualSection() const = 0;
75195098Sed  };
76210299Sed
77195098Sed} // end namespace llvm
78195098Sed
79195098Sed#endif
80