Implements low-level object file format specific output for COFF and
ELF with support for:

- File headers
- Section headers + data
- Relocations
- Symbols
- Unwind data (only COFF/Win64)

The output format follows a few rules:
- Values are almost always output one per line (as elf-dump/coff-dump already do). - Many values are translated to something readable (like enum names), with the raw value in parentheses.
- Hex numbers are output in uppercase, prefixed with "0x".
- Flags are sorted alphabetically.
- Lists and groups are always delimited.

Example output:
---------- snip ----------
Sections [
  Section {
    Index: 1
    Name: .text (5)
    Type: SHT_PROGBITS (0x1)
    Flags [ (0x6)
      SHF_ALLOC (0x2)
      SHF_EXECINSTR (0x4)
    ]
    Address: 0x0
    Offset: 0x40
    Size: 33
    Link: 0
    Info: 0
    AddressAlignment: 16
    EntrySize: 0
    Relocations [
      0x6 R_386_32 .rodata.str1.1 0x0
      0xB R_386_PC32 puts 0x0
      0x12 R_386_32 .rodata.str1.1 0x0
      0x17 R_386_PC32 puts 0x0
    ]
    SectionData (
      0000: 83EC04C7 04240000 0000E8FC FFFFFFC7  |.....$..........|
      0010: 04240600 0000E8FC FFFFFF31 C083C404  |.$.........1....|
      0020: C3                                   |.|
    )
  }
]
---------- snip ----------

Relocations and symbols can be output standalone or together with the section header as displayed in the example.
This feature set supports all tests in test/MC/COFF and test/MC/ELF (and I suspect all additional tests using elf-dump), making elf-dump and coff-dump deprecated.

Patch by Nico Rieck!

llvm-svn: 178679
diff --git a/llvm/test/tools/llvm-readobj/sections-ext.test b/llvm/test/tools/llvm-readobj/sections-ext.test
new file mode 100644
index 0000000..a972c9a
--- /dev/null
+++ b/llvm/test/tools/llvm-readobj/sections-ext.test
@@ -0,0 +1,175 @@
+RUN: llvm-readobj -s -st -sr -sd %p/Inputs/trivial.obj.coff-i386 \
+RUN:   | FileCheck %s -check-prefix COFF
+RUN: llvm-readobj -s -st -sr -sd %p/Inputs/trivial.obj.elf-i386 \
+RUN:   | FileCheck %s -check-prefix ELF
+RUN: llvm-readobj -s -st -sr -sd %p/Inputs/trivial.obj.macho-i386 \
+RUN:   | FileCheck %s -check-prefix MACHO
+
+COFF:      Sections [
+COFF-NEXT:   Section {
+COFF-NEXT:     Number: 1
+COFF-NEXT:     Name: .text (2E 74 65 78 74 00 00 00)
+COFF-NEXT:     VirtualSize: 0x0
+COFF-NEXT:     VirtualAddress: 0x0
+COFF-NEXT:     RawDataSize: 22
+COFF-NEXT:     PointerToRawData: 0x64
+COFF-NEXT:     PointerToRelocations: 0x7A
+COFF-NEXT:     PointerToLineNumbers: 0x0
+COFF-NEXT:     RelocationCount: 3
+COFF-NEXT:     LineNumberCount: 0
+COFF-NEXT:     Characteristics [ (0x60500020)
+COFF-NEXT:       IMAGE_SCN_ALIGN_16BYTES (0x500000)
+COFF-NEXT:       IMAGE_SCN_CNT_CODE (0x20)
+COFF-NEXT:       IMAGE_SCN_MEM_EXECUTE (0x20000000)
+COFF-NEXT:       IMAGE_SCN_MEM_READ (0x40000000)
+COFF-NEXT:     ]
+COFF-NEXT:     Relocations [
+COFF-NEXT:       0x4 IMAGE_REL_I386_DIR32 .data
+COFF-NEXT:       0x9 IMAGE_REL_I386_REL32 _puts
+COFF-NEXT:       0xE IMAGE_REL_I386_REL32 _SomeOtherFunction
+COFF-NEXT:     ]
+COFF-NEXT:     Symbols [
+COFF-NEXT:       Symbol {
+COFF-NEXT:         Name: .text
+COFF-NEXT:         Value: 0
+COFF-NEXT:         Section: .text (1)
+COFF-NEXT:         BaseType: Null (0x0)
+COFF-NEXT:         ComplexType: Null (0x0)
+COFF-NEXT:         StorageClass: Static (0x3)
+COFF-NEXT:         AuxSymbolCount: 1
+COFF-NEXT:         AuxSectionDef {
+COFF-NEXT:           Length: 22
+COFF-NEXT:           RelocationCount: 3
+COFF-NEXT:           LineNumberCount: 0
+COFF-NEXT:           Checksum: 0x0
+COFF-NEXT:           Number: 1
+COFF-NEXT:           Selection: 0x0
+COFF-NEXT:           Unused: (00 00 00)
+COFF-NEXT:         }
+COFF-NEXT:       }
+COFF-NEXT:       Symbol {
+COFF-NEXT:         Name: _main
+COFF-NEXT:         Value: 0
+COFF-NEXT:         Section: .text (1)
+COFF-NEXT:         BaseType: Null (0x0)
+COFF-NEXT:         ComplexType: Function (0x2)
+COFF-NEXT:         StorageClass: External (0x2)
+COFF-NEXT:         AuxSymbolCount: 0
+COFF-NEXT:       }
+COFF-NEXT:     ]
+COFF-NEXT:     SectionData (
+COFF-NEXT:       0000: 50C70424 00000000 E8000000 00E80000  |P..$............|
+COFF-NEXT:       0010: 000031C0 5AC3                        |..1.Z.|
+COFF-NEXT:     )
+COFF-NEXT:   }
+
+ELF:      Sections [
+ELF-NEXT:   Section {
+ELF-NEXT:     Index: 0
+ELF-NEXT:     Name:  (0)
+ELF-NEXT:     Type: SHT_NULL (0x0)
+ELF-NEXT:     Flags [ (0x0)
+ELF-NEXT:     ]
+ELF-NEXT:     Address: 0x0
+ELF-NEXT:     Offset: 0x0
+ELF-NEXT:     Size: 0
+ELF-NEXT:     Link: 0
+ELF-NEXT:     Info: 0
+ELF-NEXT:     AddressAlignment: 0
+ELF-NEXT:     EntrySize: 0
+ELF-NEXT:     Relocations [
+ELF-NEXT:     ]
+ELF-NEXT:     Symbols [
+ELF-NEXT:     ]
+ELF-NEXT:     SectionData (
+ELF-NEXT:     )
+ELF-NEXT:   }
+ELF-NEXT:   Section {
+ELF-NEXT:     Index: 1
+ELF-NEXT:     Name: .text (5)
+ELF-NEXT:     Type: SHT_PROGBITS (0x1)
+ELF-NEXT:     Flags [ (0x6)
+ELF-NEXT:       SHF_ALLOC (0x2)
+ELF-NEXT:       SHF_EXECINSTR (0x4)
+ELF-NEXT:     ]
+ELF-NEXT:     Address: 0x0
+ELF-NEXT:     Offset: 0x40
+ELF-NEXT:     Size: 42
+ELF-NEXT:     Link: 0
+ELF-NEXT:     Info: 0
+ELF-NEXT:     AddressAlignment: 16
+ELF-NEXT:     EntrySize: 0
+ELF-NEXT:     Relocations [
+ELF-NEXT:       0xC R_386_GOTPC _GLOBAL_OFFSET_TABLE_ 0x0
+ELF-NEXT:       0x12 R_386_GOTOFF .L.str 0x0
+ELF-NEXT:       0x1A R_386_PLT32 puts 0x0
+ELF-NEXT:       0x1F R_386_PLT32 SomeOtherFunction 0x0
+ELF-NEXT:     ]
+ELF-NEXT:     Symbols [
+ELF-NEXT:       Symbol {
+ELF-NEXT:         Name: .text (0)
+ELF-NEXT:         Value: 0x0
+ELF-NEXT:         Size: 0
+ELF-NEXT:         Binding: Local (0x0)
+ELF-NEXT:         Type: Section (0x3)
+ELF-NEXT:         Other: 0
+ELF-NEXT:         Section: .text (0x1)
+ELF-NEXT:       }
+ELF-NEXT:       Symbol {
+ELF-NEXT:         Name: main (12)
+ELF-NEXT:         Value: 0x0
+ELF-NEXT:         Size: 42
+ELF-NEXT:         Binding: Global (0x1)
+ELF-NEXT:         Type: Function (0x2)
+ELF-NEXT:         Other: 0
+ELF-NEXT:         Section: .text (0x1)
+ELF-NEXT:       }
+ELF-NEXT:     ]
+ELF-NEXT:     SectionData (
+ELF-NEXT:       0000: 5383EC08 E8000000 005B81C3 03000000  |S........[......|
+ELF-NEXT:       0010: 8D830000 00008904 24E8FCFF FFFFE8FC  |........$.......|
+ELF-NEXT:       0020: FFFFFF31 C083C408 5BC3               |...1....[.|
+ELF-NEXT:     )
+ELF-NEXT:   }
+
+MACHO:      Sections [
+MACHO-NEXT:   Section {
+MACHO-NEXT:     Index: 0
+MACHO-NEXT:     Name: __text (5F 5F 74 65 78 74 00 00 00 00 00 00 00 00 00 00)
+MACHO-NEXT:     Segment: __TEXT (5F 5F 54 45 58 54 00 00 00 00 00 00 00 00 00 00)
+MACHO-NEXT:     Address: 0x0
+MACHO-NEXT:     Size: 0x22
+MACHO-NEXT:     Offset: 324
+MACHO-NEXT:     Alignment: 4
+MACHO-NEXT:     RelocationOffset: 0x174
+MACHO-NEXT:     RelocationCount: 4
+MACHO-NEXT:     Type: 0x0
+MACHO-NEXT:     Attributes [ (0x800004)
+MACHO-NEXT:       PureInstructions (0x800000)
+MACHO-NEXT:       SomeInstructions (0x4)
+MACHO-NEXT:     ]
+MACHO-NEXT:     Reserved1: 0x0
+MACHO-NEXT:     Reserved2: 0x0
+MACHO-NEXT:     Relocations [
+MACHO-NEXT:       0x18 GENERIC_RELOC_VANILLA _SomeOtherFunction 0x0
+MACHO-NEXT:       0x13 GENERIC_RELOC_VANILLA _puts 0x0
+MACHO-NEXT:       0xB GENERIC_RELOC_LOCAL_SECTDIFF _main 0x{{[0-9A-F]+}}
+MACHO-NEXT:       0x0 GENERIC_RELOC_PAIR _main 0x{{[0-9A-F]+}}
+MACHO-NEXT:     ]
+MACHO-NEXT:     Symbols [
+MACHO-NEXT:       Symbol {
+MACHO-NEXT:         Name: _main (1)
+MACHO-NEXT:         Type: 0xF
+MACHO-NEXT:         Section: __text (0x1)
+MACHO-NEXT:         RefType: UndefinedNonLazy (0x0)
+MACHO-NEXT:         Flags [ (0x0)
+MACHO-NEXT:         ]
+MACHO-NEXT:         Value: 0x0
+MACHO-NEXT:       }
+MACHO-NEXT:     ]
+MACHO-NEXT:     SectionData (
+MACHO-NEXT:       0000: 83EC0CE8 00000000 588D801A 00000089  |........X.......|
+MACHO-NEXT:       0010: 0424E8E9 FFFFFFE8 E4FFFFFF 31C083C4  |.$..........1...|
+MACHO-NEXT:       0020: 0CC3                                 |..|
+MACHO-NEXT:     )
+MACHO-NEXT:   }