include/llvm/MC/MCSectionCOFF.h

   1 //===- MCSectionCOFF.h - COFF 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 MCSectionCOFF class.
  11 //
  12 //===----------------------------------------------------------------------===//
  13
  14 #ifndef LLVM_MC_MCSECTIONCOFF_H
  15 #define LLVM_MC_MCSECTIONCOFF_H
  16
  17 #include "llvm/MC/MCSection.h"
  18
  19 namespace llvm {
  20
  21 /// MCSectionCOFF - This represents a section on Windows
  22   class MCSectionCOFF : public MCSection {
  23     // The memory for this string is stored in the same MCContext as *this.
  24     StringRef SectionName;
  25
  26     /// Characteristics - This is the Characteristics field of a section,
  27     //  drawn from the enums below.
  28     unsigned Characteristics;
  29
  30     /// Selection - This is the Selection field for the section symbol, if
  31     /// it is a COMDAT section (Characteristics & IMAGE_SCN_LNK_COMDAT) != 0
  32     int Selection;
  33
  34   private:
  35     friend class MCContext;
  36     MCSectionCOFF(StringRef Section, unsigned Characteristics,
  37                   int Selection, SectionKind K)
  38       : MCSection(SV_COFF, K), SectionName(Section),
  39         Characteristics(Characteristics), Selection (Selection) {
  40       assert ((Characteristics & 0x00F00000) == 0 &&
  41         "alignment must not be set upon section creation");
  42     }
  43     ~MCSectionCOFF();
  44
  45   public:
  46     /// ShouldOmitSectionDirective - Decides whether a '.section' directive
  47     /// should be printed before the section name
  48     bool ShouldOmitSectionDirective(StringRef Name, const MCAsmInfo &MAI) const;
  49
  50     //FIXME: all COFF enumerations/flags should be standardized into one place...
  51     // Target/X86COFF.h doesn't seem right as COFF can be used for other targets,
  52     // MC/WinCOFF.h maybe right as it isn't target or entity specific, and it is
  53     //   pretty low on the dependancy graph (is there any need to support non
  54     //   windows COFF?)
  55     // here is good for section stuff, but others should go elsewhere
  56
  57     /// Valid section flags.
  58     enum {
  59       IMAGE_SCN_TYPE_NO_PAD                     = 0x00000008,
  60       IMAGE_SCN_CNT_CODE                        = 0x00000020,
  61       IMAGE_SCN_CNT_INITIALIZED_DATA            = 0x00000040,
  62       IMAGE_SCN_CNT_UNINITIALIZED_DATA          = 0x00000080,
  63       IMAGE_SCN_LNK_OTHER                       = 0x00000100,
  64       IMAGE_SCN_LNK_INFO                        = 0x00000200,
  65       IMAGE_SCN_LNK_REMOVE                      = 0x00000800,
  66       IMAGE_SCN_LNK_COMDAT                      = 0x00001000,
  67       IMAGE_SCN_MEM_FARDATA                     = 0x00008000,
  68       IMAGE_SCN_MEM_PURGEABLE                   = 0x00020000,
  69       IMAGE_SCN_MEM_16BIT                       = 0x00020000,
  70       IMAGE_SCN_MEM_LOCKED                      = 0x00040000,
  71       IMAGE_SCN_MEM_PRELOAD                     = 0x00080000,
  72       /* these are handled elsewhere
  73       IMAGE_SCN_ALIGN_1BYTES                    = 0x00100000,
  74       IMAGE_SCN_ALIGN_2BYTES                    = 0x00200000,
  75       IMAGE_SCN_ALIGN_4BYTES                    = 0x00300000,
  76       IMAGE_SCN_ALIGN_8BYTES                    = 0x00400000,
  77       IMAGE_SCN_ALIGN_16BYTES                   = 0x00500000,
  78       IMAGE_SCN_ALIGN_32BYTES                   = 0x00600000,
  79       IMAGE_SCN_ALIGN_64BYTES                   = 0x00700000,
  80       */
  81       IMAGE_SCN_LNK_NRELOC_OVFL                 = 0x01000000,
  82       IMAGE_SCN_MEM_DISCARDABLE                 = 0x02000000,
  83       IMAGE_SCN_MEM_NOT_CACHED                  = 0x04000000,
  84       IMAGE_SCN_MEM_NOT_PAGED                   = 0x08000000,
  85       IMAGE_SCN_MEM_SHARED                      = 0x10000000,
  86       IMAGE_SCN_MEM_EXECUTE                     = 0x20000000,
  87       IMAGE_SCN_MEM_READ                        = 0x40000000,
  88       IMAGE_SCN_MEM_WRITE                       = 0x80000000
  89     };
  90
  91     enum {
  92       IMAGE_COMDAT_SELECT_NODUPLICATES = 1,
  93       IMAGE_COMDAT_SELECT_ANY,
  94       IMAGE_COMDAT_SELECT_SAME_SIZE,
  95       IMAGE_COMDAT_SELECT_EXACT_MATCH,
  96       IMAGE_COMDAT_SELECT_ASSOCIATIVE,
  97       IMAGE_COMDAT_SELECT_LARGEST
  98     };
  99
 100     StringRef getSectionName() const { return SectionName; }
 101     unsigned getCharacteristics() const { return Characteristics; }
 102     int getSelection () const { return Selection; }
 103
 104     virtual void PrintSwitchToSection(const MCAsmInfo &MAI,
 105                                       raw_ostream &OS) const;
 106
 107     static bool classof(const MCSection *S) {
 108       return S->getVariant() == SV_COFF;
 109     }
 110     static bool classof(const MCSectionCOFF *) { return true; }
 111   };
 112
 113 } // end namespace llvm
 114
 115 #endif