[Object][COFF][llvm-readobj] Add support for ARM64X dynamic relocations. (#97229)

Author: cjacek

llvm/include/llvm/BinaryFormat/COFF.h

@@ -417,6 +417,21 @@ enum RelocationTypesARM64 : unsigned {
   IMAGE_REL_ARM64_REL32 = 0x0011,
 };
 
+enum DynamicRelocationType : unsigned {
+  IMAGE_DYNAMIC_RELOCATION_GUARD_RF_PROLOGUE = 1,
+  IMAGE_DYNAMIC_RELOCATION_GUARD_RF_EPILOGUE = 2,
+  IMAGE_DYNAMIC_RELOCATION_GUARD_IMPORT_CONTROL_TRANSFER = 3,
+  IMAGE_DYNAMIC_RELOCATION_GUARD_INDIR_CONTROL_TRANSFER = 4,
+  IMAGE_DYNAMIC_RELOCATION_GUARD_SWITCHTABLE_BRANCH = 5,
+  IMAGE_DYNAMIC_RELOCATION_ARM64X = 6,
+};
+
+enum Arm64XFixupType : uint8_t {
+  IMAGE_DVRT_ARM64X_FIXUP_TYPE_ZEROFILL = 0,
+  IMAGE_DVRT_ARM64X_FIXUP_TYPE_VALUE = 1,
+  IMAGE_DVRT_ARM64X_FIXUP_TYPE_DELTA = 2,
+};
+
 enum COMDATType : uint8_t {
   IMAGE_COMDAT_SELECT_NODUPLICATES = 1,
   IMAGE_COMDAT_SELECT_ANY,

llvm/include/llvm/Object/COFF.h

@@ -35,8 +35,10 @@ template <typename T> class ArrayRef;
 
 namespace object {
 
+class Arm64XRelocRef;
 class BaseRelocRef;
 class DelayImportDirectoryEntryRef;
+class DynamicRelocRef;
 class ExportDirectoryEntryRef;
 class ImportDirectoryEntryRef;
 class ImportedSymbolRef;
@@ -48,6 +50,8 @@ using delay_import_directory_iterator =
 using export_directory_iterator = content_iterator<ExportDirectoryEntryRef>;
 using imported_symbol_iterator = content_iterator<ImportedSymbolRef>;
 using base_reloc_iterator = content_iterator<BaseRelocRef>;
+using dynamic_reloc_iterator = content_iterator<DynamicRelocRef>;
+using arm64x_reloc_iterator = content_iterator<Arm64XRelocRef>;
 
 /// The DOS compatible header at the front of all PE/COFF executables.
 struct dos_header {
@@ -832,6 +836,37 @@ struct debug_h_header {
   support::ulittle16_t HashAlgorithm;
 };
 
+struct coff_dynamic_reloc_table {
+  support::ulittle32_t Version;
+  support::ulittle32_t Size;
+};
+
+struct coff_dynamic_relocation32 {
+  support::ulittle32_t Symbol;
+  support::ulittle32_t BaseRelocSize;
+};
+
+struct coff_dynamic_relocation64 {
+  support::ulittle64_t Symbol;
+  support::ulittle32_t BaseRelocSize;
+};
+
+struct coff_dynamic_relocation32_v2 {
+  support::ulittle32_t HeaderSize;
+  support::ulittle32_t FixupInfoSize;
+  support::ulittle32_t Symbol;
+  support::ulittle32_t SymbolGroup;
+  support::ulittle32_t Flags;
+};
+
+struct coff_dynamic_relocation64_v2 {
+  support::ulittle32_t HeaderSize;
+  support::ulittle32_t FixupInfoSize;
+  support::ulittle64_t Symbol;
+  support::ulittle32_t SymbolGroup;
+  support::ulittle32_t Flags;
+};
+
 class COFFObjectFile : public ObjectFile {
 private:
   COFFObjectFile(MemoryBufferRef Object);
@@ -861,6 +896,7 @@ class COFFObjectFile : public ObjectFile {
   // Either coff_load_configuration32 or coff_load_configuration64.
   const void *LoadConfig = nullptr;
   const chpe_metadata *CHPEMetadata = nullptr;
+  const coff_dynamic_reloc_table *DynamicRelocTable = nullptr;
 
   Expected<StringRef> getString(uint32_t offset) const;
 
@@ -880,6 +916,7 @@ class COFFObjectFile : public ObjectFile {
   Error initDebugDirectoryPtr();
   Error initTLSDirectoryPtr();
   Error initLoadConfigPtr();
+  Error initDynamicRelocPtr(uint32_t SectionIndex, uint32_t SectionOffset);
 
 public:
   static Expected<std::unique_ptr<COFFObjectFile>>
@@ -986,6 +1023,9 @@ class COFFObjectFile : public ObjectFile {
   }
 
   const chpe_metadata *getCHPEMetadata() const { return CHPEMetadata; }
+  const coff_dynamic_reloc_table *getDynamicRelocTable() const {
+    return DynamicRelocTable;
+  }
 
   StringRef getRelocationTypeName(uint16_t Type) const;
 
@@ -1054,6 +1094,8 @@ class COFFObjectFile : public ObjectFile {
   export_directory_iterator export_directory_end() const;
   base_reloc_iterator base_reloc_begin() const;
   base_reloc_iterator base_reloc_end() const;
+  dynamic_reloc_iterator dynamic_reloc_begin() const;
+  dynamic_reloc_iterator dynamic_reloc_end() const;
   const debug_directory *debug_directory_begin() const {
     return DebugDirectoryBegin;
   }
@@ -1066,6 +1108,7 @@ class COFFObjectFile : public ObjectFile {
       delay_import_directories() const;
   iterator_range<export_directory_iterator> export_directories() const;
   iterator_range<base_reloc_iterator> base_relocs() const;
+  iterator_range<dynamic_reloc_iterator> dynamic_relocs() const;
   iterator_range<const debug_directory *> debug_directories() const {
     return make_range(debug_directory_begin(), debug_directory_end());
   }
@@ -1295,6 +1338,62 @@ class BaseRelocRef {
   uint32_t Index;
 };
 
+class DynamicRelocRef {
+public:
+  DynamicRelocRef() = default;
+  DynamicRelocRef(const void *Header, const COFFObjectFile *Owner)
+      : Obj(Owner), Header(reinterpret_cast<const uint8_t *>(Header)) {}
+
+  bool operator==(const DynamicRelocRef &Other) const;
+  void moveNext();
+  uint32_t getType() const;
+  void getContents(ArrayRef<uint8_t> &Ref) const;
+
+  arm64x_reloc_iterator arm64x_reloc_begin() const;
+  arm64x_reloc_iterator arm64x_reloc_end() const;
+  iterator_range<arm64x_reloc_iterator> arm64x_relocs() const;
+
+private:
+  Error validate() const;
+
+  const COFFObjectFile *Obj;
+  const uint8_t *Header;
+
+  friend class COFFObjectFile;
+};
+
+class Arm64XRelocRef {
+public:
+  Arm64XRelocRef() = default;
+  Arm64XRelocRef(const coff_base_reloc_block_header *Header, uint32_t Index = 0)
+      : Header(Header), Index(Index) {}
+
+  bool operator==(const Arm64XRelocRef &Other) const;
+  void moveNext();
+
+  COFF::Arm64XFixupType getType() const {
+    return COFF::Arm64XFixupType((getReloc() >> 12) & 3);
+  }
+  uint32_t getRVA() const { return Header->PageRVA + (getReloc() & 0xfff); }
+  uint8_t getSize() const;
+  uint64_t getValue() const;
+
+private:
+  const support::ulittle16_t &getReloc(uint32_t Offset = 0) const {
+    return reinterpret_cast<const support::ulittle16_t *>(Header +
+                                                          1)[Index + Offset];
+  }
+
+  uint16_t getArg() const { return getReloc() >> 14; }
+  uint8_t getEntrySize() const;
+  Error validate(const COFFObjectFile *Obj) const;
+
+  const coff_base_reloc_block_header *Header;
+  uint32_t Index;
+
+  friend class DynamicRelocRef;
+};
+
 class ResourceSectionRef {
 public:
   ResourceSectionRef() = default;