[PATCH] D28303: Add iterator support to DWARFDie to allow child DIE iteration.

[Greg Clayton via Phabricator via llvm-commits]

clayborg added inline comments.


================
Comment at: unittests/DebugInfo/DWARF/DWARFDebugInfoTest.cpp:1228
+  // the DWARFDie::end() iterator.
+  EXPECT_EQ(DWARFDie::iterator(Null), Null.end());
+}
----------------
It isn't possible with the DWARF APIs currently without adding code that no one would want. 

I was able to use DwarfGenerator to generate a DWARF file that was close that I saved to disk. I then used obj2yaml to make a yaml file, edited it and got what we need:
```
--- !mach-o
FileHeader:      
  magic:           0xFEEDFACF
  cputype:         0x01000007
  cpusubtype:      0x00000003
  filetype:        0x00000001
  ncmds:           2
  sizeofcmds:      248
  flags:           0x00000000
  reserved:        0x00000000
LoadCommands:    
  - cmd:             LC_SEGMENT_64
    cmdsize:         232
    segname:         ''
    vmaddr:          0
    vmsize:          27
    fileoff:         280
    filesize:        27
    maxprot:         7
    initprot:        7
    nsects:          2
    flags:           0
    Sections:        
      - sectname:        __debug_abbrev
        segname:         __DWARF
        addr:            0x0000000000000000
        size:            5
        offset:          0x00000118
        align:           0
        reloff:          0x00000000
        nreloc:          0
        flags:           0x02000000
        reserved1:       0x00000000
        reserved2:       0x00000000
        reserved3:       0x00000000
      - sectname:        __debug_info
        segname:         __DWARF
        addr:            0x000000000000000D
        size:            14
        offset:          0x00000125
        align:           0
        reloff:          0x00000000
        nreloc:          0
        flags:           0x02000000
        reserved1:       0x00000000
        reserved2:       0x00000000
        reserved3:       0x00000000
  - cmd:             LC_VERSION_MIN_MACOSX
    cmdsize:         16
    version:         1048576
    sdk:             0
DWARF:           
  debug_abbrev:    
    - Code:            0x00000001
      Tag:             DW_TAG_compile_unit
      Children:        DW_CHILDREN_yes
      Attributes:      
  debug_info:      
    - Length:          10
      Version:         4
      AbbrOffset:      0
      AddrSize:        8
      Entries:         
        - AbbrCode:        0x00000001
          Values:          
        - AbbrCode:        0x00000000
          Values:          
...
```

Are you OK if I have this text in a "const char *" variable and use the yaml2obj APIs to create an in memory file and then parse that DWARF and then test this? I can't really use FileCheck to test this internal iteration API. Let me know if you are ok with this approach?


https://reviews.llvm.org/D28303