Add PPC64_GLINK dynamic tag

[sfertile]

Summary

Adds support for the PPC64_GLINK dynamic tag which is used in the ElfV2 abi.

[arichardson]

LGTM other than adding a gap between MIPS tags and PPC tags

include/llvm/BinaryFormat/DynamicTags.def

178

I would add a newline and a // PPC specific dynamic table entries comment

191

Good catch, I forgot to add those in my initial change.

[sfertile]

include/llvm/BinaryFormat/DynamicTags.def

178

Will do, thanks.

include/llvm/BinaryFormat/DynamicTags.def

 #define HEXAGON_DYNAMIC_TAG_DEFINED
 #endif
 
 #ifndef MIPS_DYNAMIC_TAG
 #define MIPS_DYNAMIC_TAG(name, value) DYNAMIC_TAG(name, value)
 #define MIPS_DYNAMIC_TAG_DEFINED
 #endif
 
+#ifndef PPC64_DYNAMIC_TAG
+#define PPC64_DYNAMIC_TAG(name, value) DYNAMIC_TAG(name, value)
+#define PPC64_DYNAMIC_TAG_DEFINED
+#endif
+
 #ifndef DYNAMIC_TAG_MARKER
 #define DYNAMIC_TAG_MARKER(name, value) DYNAMIC_TAG(name, value)
 #define DYNAMIC_TAG_MARKER_DEFINED
 #endif
 
 DYNAMIC_TAG(NULL, 0)        // Marks end of dynamic array.
 DYNAMIC_TAG(NEEDED, 1)      // String table offset of needed library.
 DYNAMIC_TAG(PLTRELSZ, 2)    // Size of relocation entries in PLT.
MIPS_DYNAMIC_TAG(MIPS_COMPACT_SIZE, 0x7000002F) // Size of compact relocation
                                                 // section (O32).
 MIPS_DYNAMIC_TAG(MIPS_GP_VALUE, 0x70000030)     // GP value for auxiliary GOTs.
 MIPS_DYNAMIC_TAG(MIPS_AUX_DYNAMIC, 0x70000031)  // Address of auxiliary .dynamic.
 MIPS_DYNAMIC_TAG(MIPS_PLTGOT, 0x70000032)       // Address of the base of the PLTGOT.
 MIPS_DYNAMIC_TAG(MIPS_RWPLT, 0x70000034)        // Points to the base
                                                 // of a writable PLT.
 MIPS_DYNAMIC_TAG(MIPS_RLD_MAP_REL, 0x70000035)  // Relative offset of run time loader
                                                 // map, used for debugging.
+PPC64_DYNAMIC_TAG(PPC64_GLINK, 0x70000000) // Address of 32 bytes before the
+                                           // first glink lazy resolver stub.
 
 // Sun machine-independent extensions.
 DYNAMIC_TAG(AUXILIARY, 0x7FFFFFFD) // Shared object to load before self
 DYNAMIC_TAG(FILTER, 0x7FFFFFFF)    // Shared object to get values from
 
 
 #ifdef DYNAMIC_TAG_MARKER_DEFINED
 #undef DYNAMIC_TAG_MARKER
 #endif
 #ifdef MIPS_DYNAMIC_TAG_DEFINED
 #undef MIPS_DYNAMIC_TAG
+#undef MIPS_DYNAMIC_TAG_DEFINED
 #endif
 #ifdef HEXAGON_DYNAMIC_TAG_DEFINED
 #undef HEXAGON_DYNAMIC_TAG
+#undef HEXAGON_DYNAMIC_TAG_DEFINED
+#endif
+#ifdef PPC64_DYNAMIC_TAG_DEFINED
+#undef PPC64_DYNAMIC_TAG
+#undef PPC64_DYNAMIC_TAG_DEFINED
 #endif

test/tools/llvm-readobj/ppc64-glink.test

+# Check DT_PPC64_GLINK dynamic tag.
+
+RUN: llvm-readobj -dynamic-table %p/Inputs/ppc64.exe | FileCheck %s
+
+CHECK: Format: ELF64-ppc64
+CHECK: Arch: powerpc64le
+CHECK: AddressSize: 64bit
+
+CHECK:      DynamicSection [ (25 entries)
+CHECK-NEXT:   Tag                Type                 Name/Value
+CHECK:        0x0000000070000000 PPC64_GLINK          0x10000830

tools/llvm-readobj/ELFDumper.cpp

#define DYNAMIC_TAG(n, v)
   case EM_HEXAGON:
     switch (Type) {
 #define HEXAGON_DYNAMIC_TAG(name, value)                                       \
   case DT_##name:                                                              \
     return #name;
 #include "llvm/BinaryFormat/DynamicTags.def"
 #undef HEXAGON_DYNAMIC_TAG
     }
+
   case EM_MIPS:
     switch (Type) {
 #define MIPS_DYNAMIC_TAG(name, value)                                          \
   case DT_##name:                                                              \
     return #name;
 #include "llvm/BinaryFormat/DynamicTags.def"
 #undef MIPS_DYNAMIC_TAG
     }
+
+    case EM_PPC64:
+      switch(Type) {
+#define PPC64_DYNAMIC_TAG(name, value)                                         \
+    case DT_##name:                                                            \
+      return #name;
+#include "llvm/BinaryFormat/DynamicTags.def"
+#undef PPC64_DYNAMIC_TAG
+    }
   }
 #undef DYNAMIC_TAG
   switch (Type) {
 // Now handle all dynamic tags except the architecture specific ones
 #define MIPS_DYNAMIC_TAG(name, value)
 #define HEXAGON_DYNAMIC_TAG(name, value)
+#define PPC64_DYNAMIC_TAG(name, value)
 // Also ignore marker tags such as DT_HIOS (maps to DT_VERNEEDNUM), etc.
 #define DYNAMIC_TAG_MARKER(name, value)
 #define DYNAMIC_TAG(name, value)                                               \
   case DT_##name:                                                              \
     return #name;
 #include "llvm/BinaryFormat/DynamicTags.def"
 #undef DYNAMIC_TAG
 #undef MIPS_DYNAMIC_TAG
 #undef HEXAGON_DYNAMIC_TAG
+#undef PPC64_DYNAMIC_TAG
 #undef DYNAMIC_TAG_MARKER
   default: return "unknown";
   }
 }
 
 #define LLVM_READOBJ_DT_FLAG_ENT(prefix, enum) \
   { #enum, prefix##_##enum }