include/llvm/Object/XCOFFObjectFile.h

   1 //===- XCOFFObjectFile.h - XCOFF object file implementation -----*- C++ -*-===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8 //
   9 // This file declares the XCOFFObjectFile class.
  10 //
  11 //===----------------------------------------------------------------------===//
  12
  13 #ifndef LLVM_OBJECT_XCOFFOBJECTFILE_H
  14 #define LLVM_OBJECT_XCOFFOBJECTFILE_H
  15
  16 #include "llvm/BinaryFormat/XCOFF.h"
  17 #include "llvm/Object/ObjectFile.h"
  18
  19 namespace llvm {
  20 namespace object {
  21
  22 struct XCOFFFileHeader32 {
  23   support::ubig16_t Magic;
  24   support::ubig16_t NumberOfSections;
  25
  26   // Unix time value, value of 0 indicates no timestamp.
  27   // Negative values are reserved.
  28   support::big32_t TimeStamp;
  29
  30   support::ubig32_t SymbolTableOffset; // File offset to symbol table.
  31   support::big32_t NumberOfSymTableEntries;
  32   support::ubig16_t AuxHeaderSize;
  33   support::ubig16_t Flags;
  34 };
  35
  36 struct XCOFFFileHeader64 {
  37   support::ubig16_t Magic;
  38   support::ubig16_t NumberOfSections;
  39
  40   // Unix time value, value of 0 indicates no timestamp.
  41   // Negative values are reserved.
  42   support::big32_t TimeStamp;
  43
  44   support::ubig64_t SymbolTableOffset; // File offset to symbol table.
  45   support::ubig16_t AuxHeaderSize;
  46   support::ubig16_t Flags;
  47   support::ubig32_t NumberOfSymTableEntries;
  48 };
  49
  50 struct XCOFFSectionHeader32 {
  51   char Name[XCOFF::NameSize];
  52   support::ubig32_t PhysicalAddress;
  53   support::ubig32_t VirtualAddress;
  54   support::ubig32_t SectionSize;
  55   support::ubig32_t FileOffsetToRawData;
  56   support::ubig32_t FileOffsetToRelocationInfo;
  57   support::ubig32_t FileOffsetToLineNumberInfo;
  58   support::ubig16_t NumberOfRelocations;
  59   support::ubig16_t NumberOfLineNumbers;
  60   support::big32_t Flags;
  61
  62   StringRef getName() const;
  63 };
  64
  65 struct XCOFFSectionHeader64 {
  66   char Name[XCOFF::NameSize];
  67   support::ubig64_t PhysicalAddress;
  68   support::ubig64_t VirtualAddress;
  69   support::ubig64_t SectionSize;
  70   support::big64_t FileOffsetToRawData;
  71   support::big64_t FileOffsetToRelocationInfo;
  72   support::big64_t FileOffsetToLineNumberInfo;
  73   support::ubig32_t NumberOfRelocations;
  74   support::ubig32_t NumberOfLineNumbers;
  75   support::big32_t Flags;
  76   char Padding[4];
  77
  78   StringRef getName() const;
  79 };
  80
  81 struct XCOFFSymbolEntry {
  82   enum { NAME_IN_STR_TBL_MAGIC = 0x0 };
  83   typedef struct {
  84     support::big32_t Magic; // Zero indicates name in string table.
  85     support::ubig32_t Offset;
  86   } NameInStrTblType;
  87
  88   typedef struct {
  89     uint8_t LanguageId;
  90     uint8_t CpuTypeId;
  91   } CFileLanguageIdAndTypeIdType;
  92
  93   union {
  94     char SymbolName[XCOFF::NameSize];
  95     NameInStrTblType NameInStrTbl;
  96   };
  97
  98   support::ubig32_t Value; // Symbol value; storage class-dependent.
  99   support::big16_t SectionNumber;
 100
 101   union {
 102     support::ubig16_t SymbolType;
 103     CFileLanguageIdAndTypeIdType CFileLanguageIdAndTypeId;
 104   };
 105
 106   XCOFF::StorageClass StorageClass;
 107   uint8_t NumberOfAuxEntries;
 108 };
 109
 110 struct XCOFFStringTable {
 111   uint32_t Size;
 112   const char *Data;
 113 };
 114
 115 class XCOFFObjectFile : public ObjectFile {
 116 private:
 117   const void *FileHeader = nullptr;
 118   const void *SectionHeaderTable = nullptr;
 119
 120   const XCOFFSymbolEntry *SymbolTblPtr = nullptr;
 121   XCOFFStringTable StringTable = {0, nullptr};
 122
 123   const XCOFFFileHeader32 *fileHeader32() const;
 124   const XCOFFFileHeader64 *fileHeader64() const;
 125
 126   const XCOFFSectionHeader32 *sectionHeaderTable32() const;
 127   const XCOFFSectionHeader64 *sectionHeaderTable64() const;
 128
 129   size_t getFileHeaderSize() const;
 130   size_t getSectionHeaderSize() const;
 131
 132   const XCOFFSectionHeader32 *toSection32(DataRefImpl Ref) const;
 133   const XCOFFSectionHeader64 *toSection64(DataRefImpl Ref) const;
 134   void checkSectionAddress(uintptr_t Addr, uintptr_t TableAddr) const;
 135   uintptr_t getSectionHeaderTableAddress() const;
 136
 137   // This returns a pointer to the start of the storage for the name field of
 138   // the 32-bit or 64-bit SectionHeader struct. This string is *not* necessarily
 139   // null-terminated.
 140   const char *getSectionNameInternal(DataRefImpl Sec) const;
 141
 142   int32_t getSectionFlags(DataRefImpl Sec) const;
 143
 144   static bool isReservedSectionNumber(int16_t SectionNumber);
 145   Expected<DataRefImpl> getSectionByNum(int16_t Num) const;
 146
 147   // Constructor and "create" factory function. The constructor is only a thin
 148   // wrapper around the base constructor. The "create" function fills out the
 149   // XCOFF-specific information and performs the error checking along the way.
 150   XCOFFObjectFile(unsigned Type, MemoryBufferRef Object);
 151   static Expected<std::unique_ptr<XCOFFObjectFile>> create(unsigned Type,
 152                                                            MemoryBufferRef MBR);
 153
 154   // Helper for parsing the StringTable. Returns an 'Error' if parsing failed
 155   // and an XCOFFStringTable if parsing succeeded.
 156   static Expected<XCOFFStringTable> parseStringTable(const XCOFFObjectFile *Obj,
 157                                                      uint64_t Offset);
 158
 159   // Make a friend so it can call the private 'create' function.
 160   friend Expected<std::unique_ptr<ObjectFile>>
 161   ObjectFile::createXCOFFObjectFile(MemoryBufferRef Object, unsigned FileType);
 162
 163 public:
 164   // Interface inherited from base classes.
 165   void moveSymbolNext(DataRefImpl &Symb) const override;
 166   uint32_t getSymbolFlags(DataRefImpl Symb) const override;
 167   basic_symbol_iterator symbol_begin() const override;
 168   basic_symbol_iterator symbol_end() const override;
 169
 170   Expected<StringRef> getSymbolName(DataRefImpl Symb) const override;
 171   Expected<uint64_t> getSymbolAddress(DataRefImpl Symb) const override;
 172   uint64_t getSymbolValueImpl(DataRefImpl Symb) const override;
 173   uint64_t getCommonSymbolSizeImpl(DataRefImpl Symb) const override;
 174   Expected<SymbolRef::Type> getSymbolType(DataRefImpl Symb) const override;
 175   Expected<section_iterator> getSymbolSection(DataRefImpl Symb) const override;
 176
 177   void moveSectionNext(DataRefImpl &Sec) const override;
 178   Expected<StringRef> getSectionName(DataRefImpl Sec) const override;
 179   uint64_t getSectionAddress(DataRefImpl Sec) const override;
 180   uint64_t getSectionIndex(DataRefImpl Sec) const override;
 181   uint64_t getSectionSize(DataRefImpl Sec) const override;
 182   Expected<ArrayRef<uint8_t>>
 183   getSectionContents(DataRefImpl Sec) const override;
 184   uint64_t getSectionAlignment(DataRefImpl Sec) const override;
 185   bool isSectionCompressed(DataRefImpl Sec) const override;
 186   bool isSectionText(DataRefImpl Sec) const override;
 187   bool isSectionData(DataRefImpl Sec) const override;
 188   bool isSectionBSS(DataRefImpl Sec) const override;
 189
 190   bool isSectionVirtual(DataRefImpl Sec) const override;
 191   relocation_iterator section_rel_begin(DataRefImpl Sec) const override;
 192   relocation_iterator section_rel_end(DataRefImpl Sec) const override;
 193
 194   void moveRelocationNext(DataRefImpl &Rel) const override;
 195   uint64_t getRelocationOffset(DataRefImpl Rel) const override;
 196   symbol_iterator getRelocationSymbol(DataRefImpl Rel) const override;
 197   uint64_t getRelocationType(DataRefImpl Rel) const override;
 198   void getRelocationTypeName(DataRefImpl Rel,
 199                              SmallVectorImpl<char> &Result) const override;
 200
 201   section_iterator section_begin() const override;
 202   section_iterator section_end() const override;
 203   uint8_t getBytesInAddress() const override;
 204   StringRef getFileFormatName() const override;
 205   Triple::ArchType getArch() const override;
 206   SubtargetFeatures getFeatures() const override;
 207   Expected<uint64_t> getStartAddress() const override;
 208   bool isRelocatableObject() const override;
 209
 210   // Below here is the non-inherited interface.
 211   bool is64Bit() const;
 212
 213   const XCOFFSymbolEntry *getPointerToSymbolTable() const {
 214     assert(!is64Bit() && "Symbol table handling not supported yet.");
 215     return SymbolTblPtr;
 216   }
 217
 218   Expected<StringRef>
 219   getSymbolSectionName(const XCOFFSymbolEntry *SymEntPtr) const;
 220
 221   const XCOFFSymbolEntry *toSymbolEntry(DataRefImpl Ref) const;
 222
 223   // File header related interfaces.
 224   uint16_t getMagic() const;
 225   uint16_t getNumberOfSections() const;
 226   int32_t getTimeStamp() const;
 227
 228   // Symbol table offset and entry count are handled differently between
 229   // XCOFF32 and XCOFF64.
 230   uint32_t getSymbolTableOffset32() const;
 231   uint64_t getSymbolTableOffset64() const;
 232
 233   // Note that this value is signed and might return a negative value. Negative
 234   // values are reserved for future use.
 235   int32_t getRawNumberOfSymbolTableEntries32() const;
 236
 237   // The sanitized value appropriate to use as an index into the symbol table.
 238   uint32_t getLogicalNumberOfSymbolTableEntries32() const;
 239
 240   uint32_t getNumberOfSymbolTableEntries64() const;
 241
 242   uint16_t getOptionalHeaderSize() const;
 243   uint16_t getFlags() const;
 244
 245   // Section header table related interfaces.
 246   ArrayRef<XCOFFSectionHeader32> sections32() const;
 247   ArrayRef<XCOFFSectionHeader64> sections64() const;
 248 }; // XCOFFObjectFile
 249
 250 } // namespace object
 251 } // namespace llvm
 252
 253 #endif // LLVM_OBJECT_XCOFFOBJECTFILE_H