Add ELFOSABI_FIRST_ARCH, ELFOSABI_LAST_ARCH and start using those in llvm-readobj

[kzhuravl]

Summary

ELFOSABI value range 64-255 is architecture-specific.

[kzhuravl]

Rebase on top of trunk

[t-tye]

include/llvm/BinaryFormat/ELF.h

356 ↗

(On Diff #117226)

// First architecture-specific OS ABI

357–360 ↗

(On Diff #117226)

Suggest group by architecture.

362 ↗

(On Diff #117226)

// Last architecture-specific OS ABI

tools/llvm-readobj/ELFDumper.cpp

3525 ↗

(On Diff #117226)

Should the range checking also apply to the other architecture cases:

ELFOSABI_C6000_ELFABI = 64, // Bare-metal TMS320C6000
ELFOSABI_C6000_LINUX = 65,  // Linux TMS320C6000
ELFOSABI_ARM = 97,          // ARM

Not sure where ELFOSABI_STANDALONE belongs so maybe treat it as a non-architecture value even though it is in the range.

For example:

auto OSABI = makeArrayRef(ElfOSABI);
if (e->e_ident[ELF::EI_OSABI] >= ELF::ELFOSABI_FIRST_ARCH &&
    e->e_ident[ELF::EI_OSABI] <= ELF::ELFOSABI_LAST_ARCH) {
  switch (e->e_machine) {
  case ELF::EM_ARM:
    OSABI = makeArrayRef(ARMElfOSABI);
    break;
  case ELF::EM_TI_C6000:
    OSABI = makeArrayRef(C6000ElfOSABI);
    break;
  case ELF::EM_AMDGPU:
    OSABI = makeArrayRef(AMDGPUElfOSABI);
    break;
  }
}
W.printEnum("OS/ABI", e->e_ident[ELF::EI_OSABI], OSABI);

[kzhuravl]

Address review feedback.

[t-tye]

LGTM

llvm/trunk/include/llvm/BinaryFormat/ELF.h

enum {
   ELFOSABI_TRU64 = 10,        // TRU64 UNIX
   ELFOSABI_MODESTO = 11,      // Novell Modesto
   ELFOSABI_OPENBSD = 12,      // OpenBSD
   ELFOSABI_OPENVMS = 13,      // OpenVMS
   ELFOSABI_NSK = 14,          // Hewlett-Packard Non-Stop Kernel
   ELFOSABI_AROS = 15,         // AROS
   ELFOSABI_FENIXOS = 16,      // FenixOS
   ELFOSABI_CLOUDABI = 17,     // Nuxi CloudABI
-  ELFOSABI_C6000_ELFABI = 64, // Bare-metal TMS320C6000
+  ELFOSABI_FIRST_ARCH = 64,   // First architecture-specific OS ABI
   ELFOSABI_AMDGPU_HSA = 64,   // AMD HSA runtime
+  ELFOSABI_C6000_ELFABI = 64, // Bare-metal TMS320C6000
   ELFOSABI_C6000_LINUX = 65,  // Linux TMS320C6000
   ELFOSABI_ARM = 97,          // ARM
-  ELFOSABI_STANDALONE = 255   // Standalone (embedded) application
+  ELFOSABI_STANDALONE = 255,  // Standalone (embedded) application
+  ELFOSABI_LAST_ARCH = 255    // Last Architecture-specific OS ABI
 };
 
 #define ELF_RELOC(name, value) name = value,
 
 // X86_64 relocations.
 enum {
 #include "ELFRelocs/x86_64.def"
 };

llvm/trunk/tools/llvm-readobj/ELFDumper.cpp

static const EnumEntry<unsigned> ElfOSABI[] = {
   {"TRU64",        "UNIX - TRU64",         ELF::ELFOSABI_TRU64},
   {"Modesto",      "Novell - Modesto",     ELF::ELFOSABI_MODESTO},
   {"OpenBSD",      "UNIX - OpenBSD",       ELF::ELFOSABI_OPENBSD},
   {"OpenVMS",      "VMS - OpenVMS",        ELF::ELFOSABI_OPENVMS},
   {"NSK",          "HP - Non-Stop Kernel", ELF::ELFOSABI_NSK},
   {"AROS",         "AROS",                 ELF::ELFOSABI_AROS},
   {"FenixOS",      "FenixOS",              ELF::ELFOSABI_FENIXOS},
   {"CloudABI",     "CloudABI",             ELF::ELFOSABI_CLOUDABI},
-  {"C6000_ELFABI", "Bare-metal C6000",     ELF::ELFOSABI_C6000_ELFABI},
-  {"C6000_LINUX",  "Linux C6000",          ELF::ELFOSABI_C6000_LINUX},
-  {"ARM",          "ARM",                  ELF::ELFOSABI_ARM},
   {"Standalone",   "Standalone App",       ELF::ELFOSABI_STANDALONE}
 };
 
+static const EnumEntry<unsigned> AMDGPUElfOSABI[] = {
+  {"AMDGPU_HSA", "AMDGPU - HSA", ELF::ELFOSABI_AMDGPU_HSA}
+};
+
+static const EnumEntry<unsigned> ARMElfOSABI[] = {
+  {"ARM", "ARM", ELF::ELFOSABI_ARM}
+};
+
+static const EnumEntry<unsigned> C6000ElfOSABI[] = {
+  {"C6000_ELFABI", "Bare-metal C6000", ELF::ELFOSABI_C6000_ELFABI},
+  {"C6000_LINUX",  "Linux C6000",      ELF::ELFOSABI_C6000_LINUX}
+};
+
 static const EnumEntry<unsigned> ElfMachineType[] = {
   ENUM_ENT(EM_NONE,          "None"),
   ENUM_ENT(EM_M32,           "WE32100"),
   ENUM_ENT(EM_SPARC,         "Sparc"),
   ENUM_ENT(EM_386,           "Intel 80386"),
   ENUM_ENT(EM_68K,           "MC68000"),
   ENUM_ENT(EM_88K,           "MC88000"),
   ENUM_ENT(EM_IAMCU,         "EM_IAMCU"),
const Elf_Ehdr *e = Obj->getHeader();
     {
       DictScope D(W, "Ident");
       W.printBinary("Magic", makeArrayRef(e->e_ident).slice(ELF::EI_MAG0, 4));
       W.printEnum("Class", e->e_ident[ELF::EI_CLASS], makeArrayRef(ElfClass));
       W.printEnum("DataEncoding", e->e_ident[ELF::EI_DATA],
                   makeArrayRef(ElfDataEncoding));
       W.printNumber("FileVersion", e->e_ident[ELF::EI_VERSION]);
 
-      // Handle architecture specific OS/ABI values.
-      if (e->e_machine == ELF::EM_AMDGPU &&
-          e->e_ident[ELF::EI_OSABI] == ELF::ELFOSABI_AMDGPU_HSA)
-        W.printHex("OS/ABI", "AMDGPU_HSA", ELF::ELFOSABI_AMDGPU_HSA);
-      else
-        W.printEnum("OS/ABI", e->e_ident[ELF::EI_OSABI],
-                    makeArrayRef(ElfOSABI));
+      auto OSABI = makeArrayRef(ElfOSABI);
+      if (e->e_ident[ELF::EI_OSABI] >= ELF::ELFOSABI_FIRST_ARCH &&
+          e->e_ident[ELF::EI_OSABI] <= ELF::ELFOSABI_LAST_ARCH) {
+        switch (e->e_machine) {
+        case ELF::EM_AMDGPU:
+          OSABI = makeArrayRef(AMDGPUElfOSABI);
+          break;
+        case ELF::EM_ARM:
+          OSABI = makeArrayRef(ARMElfOSABI);
+          break;
+        case ELF::EM_TI_C6000:
+          OSABI = makeArrayRef(C6000ElfOSABI);
+          break;
+        }
+      }
+      W.printEnum("OS/ABI", e->e_ident[ELF::EI_OSABI], OSABI);
       W.printNumber("ABIVersion", e->e_ident[ELF::EI_ABIVERSION]);
       W.printBinary("Unused", makeArrayRef(e->e_ident).slice(ELF::EI_PAD));
     }
 
     W.printEnum("Type", e->e_type, makeArrayRef(ElfObjectFileType));
     W.printEnum("Machine", e->e_machine, makeArrayRef(ElfMachineType));
     W.printNumber("Version", e->e_version);
     W.printHex("Entry", e->e_entry);