[DWARFYAML] Add support for referencing different abbrev tables.

[Higuoxing]

Summary

This patch adds support for referencing different abbrev tables. We use
'ID' to distinguish abbrev tables and use 'AbbrevTableID' to explicitly
assign an abbrev table to compilation units.

The syntax is:

debug_abbrev:
  - ID: 0
    Table:
      ...
  - ID: 1
    Table:
      ...
debug_info:
  - ...
    AbbrevTableID: 1 ## Reference the second abbrev table.
  - ...
    AbbrevTableID: 0 ## Reference the first abbrev table.

[Higuoxing]

Newly added tests are marked by inline comments since too many tests are updated 😂.

llvm/test/ObjectYAML/MachO/DWARF-debug_info.yaml

679

Added test.

792

Added test.

llvm/test/tools/yaml2obj/ELF/DWARF/debug-info.yaml

652

Added test.

[labath]

What would you say if, instead of AbbrevTableIndex, we had a field like AbbrevTableID. The main difference would be that this "ID" field can be explicitly specified on the Abbrev table, and it does not have to be a sequentially increasing number (though it could of course be that by default).

The thing I'm trying to achieve is to make the yaml more robust against modifications/simplifications. E.g., it would be nice if deleting an abbrev table does not make all compile units suddenly refer to different tables. If the ids were present explicitly, compile units would be unaffected by this, and one would get an explicit error message if there was a compile unit left which still referred to the deleted abbrev table.

(This is one of the aspects where an assembler is better than yaml, as symbolic labels in asm have these properties.)

[Higuoxing]

In D83116#2130019, @labath wrote:

What would you say if, instead of AbbrevTableIndex, we had a field like AbbrevTableID. The main difference would be that this "ID" field can be explicitly specified on the Abbrev table, and it does not have to be a sequentially increasing number (though it could of course be that by default).

I think it works. I'm fine with this approach, let's see what others thinking. Thanks a lot for sharing your ideas!

debug_abbrev:
  - ID: 1
    Table:
      - Code: 1
        Tag:  DW_TAG_something
        Children: DW_CHILDREN_yes
        Attributes:
          - Attribute: DW_AT_something
            Form:      DW_FORM_something
  - ID: 2
    Table:
      - Code: 1
        Tag:  DW_TAG_something
        Children: DW_CHILDREN_yes
        Attributes:
          - Attribute: DW_AT_something
            Form:      DW_FORM_something
  - ID: 3
    Table:
      - Code: 1
        Tag:  DW_TAG_something
        Children: DW_CHILDREN_yes
        Attributes:
          - Attribute: DW_AT_something
            Form:      DW_FORM_something

debug_info:
  - Length:        0x1234
    Version:       4
    AbbrevTableID: 3 ## references table 3
    ...
    Entries:
      - AbbrevCode: 1
        Values:
          - Value: 0x1234
  - Length:        0x1234
    Version:       4
    AbbrevTableID: 2 ## references table 2
    ...
    Entries:
      - AbbrevCode: 1
        Values:
          - Value: 0x1234
  - Length:        0x1234
    Version:       4
    AbbrevTableID: 1 ## references table 1
    ...
    Entries:
      - AbbrevCode: 1
        Values:
          - Value: 0x1234

[jhenderson]

In D83116#2130019, @labath wrote:

What would you say if, instead of AbbrevTableIndex, we had a field like AbbrevTableID. The main difference would be that this "ID" field can be explicitly specified on the Abbrev table, and it does not have to be a sequentially increasing number (though it could of course be that by default).

The thing I'm trying to achieve is to make the yaml more robust against modifications/simplifications. E.g., it would be nice if deleting an abbrev table does not make all compile units suddenly refer to different tables. If the ids were present explicitly, compile units would be unaffected by this, and one would get an explicit error message if there was a compile unit left which still referred to the deleted abbrev table.

(This is one of the aspects where an assembler is better than yaml, as symbolic labels in asm have these properties.)

+1 to this idea. By default it could of course be an incremental index, when emitting, but in yaml2obj, I see no reason for it to be tied in that way necessarily.

lldb/unittests/Symbol/Inputs/inlined-functions.yaml

351

AbbrevTableIndex should be an optional value. I think by default it should pick the first table (or possibly should pick the Nth table, where N is the .debug_info table index). Thus in this and pretty much every other case, you should be able to omit the new value.

llvm/test/tools/yaml2obj/ELF/DWARF/debug-info.yaml

659

Perhaps worth including the index and table count values in this error message to make it easier for people to identify the problem.

llvm/tools/obj2yaml/dwarf2yaml.cpp

19

I'm slightly surprised you needed to add this. Did this not compile without it?

[Higuoxing]

llvm/tools/obj2yaml/dwarf2yaml.cpp

19

I guess it was automatically added by the code completion tool.

[Higuoxing]

In this revision, I added a helper struct called DWARFState. When emitting DWARF sections, we should initialize DWARFState first, it will help us make DWARF sections interlinked.

Now, we are able to use AbbrevTableID to reference abbrev tables and use ID to assign a number as abbrev table's ID.

[Higuoxing]

Suppress clang-format warnings.

[jhenderson]

llvm/include/llvm/ObjectYAML/DWARFEmitter.h

34

Would it make any sense to merge the DWARFYAML::Data class and DWARFYAML::DWARFState class at all?

35

Can you use std::unordered_map here? Do we need deterministic ordering? Might also be worth naming it something like AbbrevTableID2Index to avoid confusing with the AbbrevCode values.

llvm/lib/ObjectYAML/DWARFEmitter.cpp

93

Maybe to avoid weird errors, it might make sense to disallow mixing the two methods, i.e. if one table has an explicit ID, the others all must do too. What do you think? It may not be worth it if the code is more complex, I don't know.

106

Could you use the return value of insert to identify whether the key already exists in the map? That way, you don't need the explicit count call.

315–322

It might make more sense to do this work in the caller of this function, and to maintain this function's interface.

llvm/lib/ObjectYAML/MachOEmitter.cpp

271

llvm/test/ObjectYAML/MachO/DWARF-debug_info.yaml

679–681

Is there any particular reason you don't have something equivalent to this in the ELF testing, to show you can have tables out-of-order etc.

711

Something's not right here - the YAML below has four debug_info tables, but only three have check lines. What happened to the one that should be referencing abbrev table 2?

873–884

Can you omit the abbrev section entirely?

906–911

This feels like it belongs in a debug_abbrev dedicated test?

llvm/test/tools/yaml2obj/ELF/DWARF/debug-info.yaml

924–925

Same as Mach-O, this really is a debug_abbrev test, not a debug_info test.

[labath]

This seems fairly straight-forward to me, though I didn't dive into all the details.

Given the amount of changed tests, it may be nice to separate the format change from the linking patch (so in the interim state, one could generate multiple abbrev tables, but there would be no (reasonable) way to reference any table except the first one).

llvm/include/llvm/ObjectYAML/DWARFEmitter.h

34

That would definitely be nice.

llvm/lib/ObjectYAML/DWARFEmitter.cpp

90

If you'd do all this work in the factory function and then just pass in a finished map to the constructor, there'd be no need for the ErrorAsOutParameter thingy.

92

consider: for (auto &Abbr : enumerate(DI.DebugAbbrev))

94–96

ID = DI.DebugAbbrev[I].ID.getValueOr(I)

[Higuoxing]

llvm/include/llvm/ObjectYAML/DWARFEmitter.h

34

@jhenderson :

Would it make any sense to merge the DWARFYAML::Data class and DWARFYAML::DWARFState class at all?

@labath :

That would definitely be nice.

I think they can be merged. But is there any particular reason to merge them? Personally, I would like to keep the DWARFYAML::DWARFState class. Here are a few concerns I would like to address:

• If we merge the DWARFYAML::DWARFState and DWARFYAML::Data at all, we will need to add some helper variables, e.g. AbbrevTableID2Index and a method like Error DWARFYAML::link() to DWARFYAML::Data class to link DWARF sections. We will have to call this special method before DWARF sections being emitted. If we port DWARF support to other binary format in the future, e.g., wasm, we might forget to call this method. If we make DWARF emitters accept DWARFYAML::DWARFState, it's easy to figure out that we need a DWARFState before emitting DWARF sections.

• Besides, I think DWARFYAML::Data and DWARFYAML::DWARFState have different functions. DWARFYAML::Data is used to contain original DWARF section descriptions and DWARFYAML::DWARFState contains helper structs and methods which helps link DWARF sections. It might be good not to merge them so that we can easily figure out when and where are those sections get linked?

I can be persuaded :-)

[jhenderson]

llvm/include/llvm/ObjectYAML/DWARFEmitter.h

34

I think they can be merged. But is there any particular reason to merge them?

As things stand, it mostly seems like DWARFState merely gets in the way of accessing the Data class. It seems to me like it would be easier to use if the two were one class, as you wouldn't have to keep going through an extra function call/member access.

• If we merge the DWARFYAML::DWARFState and DWARFYAML::Data at all, we will need to add some helper variables, e.g. AbbrevTableID2Index and a method like Error DWARFYAML::link() to DWARFYAML::Data class to link DWARF sections. We will have to call this special method before DWARF sections being emitted. If we port DWARF support to other binary format in the future, e.g., wasm, we might forget to call this method. If we make DWARF emitters accept DWARFYAML::DWARFState, it's easy to figure out that we need a DWARFState before emitting DWARF sections.

If, rather than do all the calculations up front (e.g. mapping tables to IDs), you put the Data members behind getters, you could then add the "linking" code there. For example, with the AbbrevTable ID mapping, you could have the getAbbrevTableIndexByID method, which is the only way of getting an abbrev table from outside the class. The first time this is called (or optionally every time), it works out the mapping between ID(s) and table(s). This avoids the need for an explicit link or finalize method.

• Besides, I think DWARFYAML::Data and DWARFYAML::DWARFState have different functions. DWARFYAML::Data is used to contain original DWARF section descriptions and DWARFYAML::DWARFState contains helper structs and methods which helps link DWARF sections. It might be good not to merge them so that we can easily figure out when and where are those sections get linked?

I'm not sure I agree they have different functions. The AbbrevID2Index map is just a helper variable that is directly derived from the Data struct's members. We could get rid of it entirely, and just move the getAbbrevTableIndexByID method into Data, rewriting it to just run through the list of tables each time to find the right ID. This is obviously less efficient than instantiating a mapping up front, if done repeatedly, but I think it indicates that this extra layer is not actually doing anything distinct. Similar principles apply probably for other things, although without further concrete examples, it's hard to discuss them!

[Higuoxing]

Merge DWARFYAML::Data and DWARFYAML::DWARFState.

llvm/include/llvm/ObjectYAML/DWARFEmitter.h

34

Thanks for the explanation!

llvm/lib/ObjectYAML/DWARFEmitter.cpp

90

DWARFYAML::DWARFState is merged into DWARFYAML::Data, so we don't need ErrorAsOutParameter any more.

93

I think it's a little bit difficult to distinguish these 2 situations. Besides, sometimes we might want to add one compilation unit to a test case and let it reference an existing abbrev table. We don't need to mutate the whole test case to add IDs. What do think of it?

[Higuoxing]

llvm/test/ObjectYAML/MachO/DWARF-debug_abbrev.yaml

423

I will remove this blank line later.

[jhenderson]

I'm not sure if my test comments have been looked at. Could you mark them as Done if you think you have addressed them, please?

llvm/include/llvm/ObjectYAML/DWARFYAML.h

233–236

Something to consider here: the user-visible behaviour of this class is that this is a const operation, but because this method causes AbbrevTableID2Index to be populated on the first call, it technically isn't. I would say this is a reasonable use case for mutable - the cache (in this case AbbrevTableID2Index) is marked as mutable, and then you can continue to pass this class around as const.

llvm/lib/ObjectYAML/DWARFEmitter.cpp

93

Leave it as is. I wasn't convinced by my own statement, so I think what you've got is fine.

[Higuoxing]

Address comments.

llvm/lib/ObjectYAML/DWARFEmitter.cpp

315–322

This is discussed in D86194

llvm/test/ObjectYAML/MachO/DWARF-debug_info.yaml

679–681

Added in test/tools/yaml2obj/ELF/DWARF/debug-info.yaml (o)

711

Sorry, the length and offsets are calculated by myself, and the __debug_info section's length is miscalculated to be 60, which should be 67. I've corrected it.

llvm/test/tools/yaml2obj/ELF/DWARF/debug-info.yaml

659

I've included the abbrev table ID and compilation unit count values in test case (n). Can we prettify the error message in test case (i) in a follow-up patch?

[jhenderson]

LGTM. Thanks!

llvm/test/tools/yaml2obj/ELF/DWARF/debug-info.yaml

659

That's fine.

[Higuoxing]

Rebase.

[Higuoxing]

This change is causing build failure, I'm going to revise this change.

[Higuoxing]

Fix incorrect format string.

[Higuoxing]

Add missing test.

[Higuoxing]

Hi @jhenderson

This change is causing build failure on armv7 platform and I've fixed it.

See: http://lab.llvm.org:8011/builders/clang-cmake-armv7-global-isel/builds/10400 and http://lab.llvm.org:8011/builders/clang-cmake-armv7-quick/builds/20261

Could you please review this change again? Thanks a lot!

llvm/lib/ObjectYAML/DWARFYAML.cpp

67

The build failure is caused by the incorrect format string. AbbrevTable.index() returns size_t and it was formatted as %u. We should use %zu here.

[jhenderson]

Looks good!

lldb/test/API/functionalities/source-map/a.yaml

debug_str:
     - 'Apple LLVM version 10.0.1 (clang-1001.0.37.3)'
     - './Trivial/main.c'
     - '.'
     - main
     - int
     - argc
     - argv
     - char
-  debug_abbrev:    
+  debug_abbrev:
+    - Table:
         - Code:            0x00000001
           Tag:             DW_TAG_compile_unit
           Children:        DW_CHILDREN_yes
-      Attributes:      
+          Attributes:
             - Attribute:       DW_AT_producer
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_language
               Form:            DW_FORM_data2
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_stmt_list
               Form:            DW_FORM_sec_offset
             - Attribute:       DW_AT_comp_dir
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_low_pc
               Form:            DW_FORM_addr
             - Attribute:       DW_AT_high_pc
               Form:            DW_FORM_data4
         - Code:            0x00000002
           Tag:             DW_TAG_subprogram
           Children:        DW_CHILDREN_yes
-      Attributes:      
+          Attributes:
             - Attribute:       DW_AT_low_pc
               Form:            DW_FORM_addr
             - Attribute:       DW_AT_high_pc
               Form:            DW_FORM_data4
             - Attribute:       DW_AT_frame_base
               Form:            DW_FORM_exprloc
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_decl_file
               Form:            DW_FORM_data1
             - Attribute:       DW_AT_decl_line
               Form:            DW_FORM_data1
             - Attribute:       DW_AT_prototyped
               Form:            DW_FORM_flag_present
             - Attribute:       DW_AT_type
               Form:            DW_FORM_ref4
             - Attribute:       DW_AT_external
               Form:            DW_FORM_flag_present
         - Code:            0x00000003
           Tag:             DW_TAG_formal_parameter
           Children:        DW_CHILDREN_no
-      Attributes:      
+          Attributes:
             - Attribute:       DW_AT_location
               Form:            DW_FORM_exprloc
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_decl_file
               Form:            DW_FORM_data1
             - Attribute:       DW_AT_decl_line
               Form:            DW_FORM_data1
             - Attribute:       DW_AT_type
               Form:            DW_FORM_ref4
         - Code:            0x00000004
           Tag:             DW_TAG_base_type
           Children:        DW_CHILDREN_no
-      Attributes:      
+          Attributes:
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_encoding
               Form:            DW_FORM_data1
             - Attribute:       DW_AT_byte_size
               Form:            DW_FORM_data1
         - Code:            0x00000005
           Tag:             DW_TAG_pointer_type
           Children:        DW_CHILDREN_no
-      Attributes:      
+          Attributes:
             - Attribute:       DW_AT_type
               Form:            DW_FORM_ref4
         - Code:            0x00000006
           Tag:             DW_TAG_const_type
           Children:        DW_CHILDREN_no
-      Attributes:      
+          Attributes:
             - Attribute:       DW_AT_type
               Form:            DW_FORM_ref4
   debug_info:      
     - Length:          122
       Version:         4
       AbbrOffset:      0
       AddrSize:        8
       Entries:         
         - AbbrCode:        0x00000001
           Values:          

lldb/unittests/Expression/DWARFExpressionTest.cpp

 //===-- DWARFExpressionTest.cpp -------------------------------------------===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
 
 #include "lldb/Expression/DWARFExpression.h"
 #include "Plugins/TypeSystem/Clang/TypeSystemClang.h"
 #include "TestingSupport/Symbol/YAMLModuleTester.h"
 #include "lldb/Core/Value.h"
 #include "lldb/Core/dwarf.h"
 #include "lldb/Symbol/ObjectFile.h"
 #include "lldb/Utility/StreamString.h"
 #include "llvm/ADT/StringExtras.h"
 #include "llvm/Testing/Support/Error.h"
TEST(DWARFExpression, DW_OP_pick) {
   EXPECT_THAT_EXPECTED(Evaluate({DW_OP_lit1, DW_OP_lit0, DW_OP_pick, 2}),
                        llvm::Failed());
 }
 
 TEST(DWARFExpression, DW_OP_convert) {
   /// Auxiliary debug info.
   const char *yamldata =
       "debug_abbrev:\n"
-      "  - Code:            0x00000001\n"
-      "    Tag:             DW_TAG_compile_unit\n"
-      "    Children:        DW_CHILDREN_yes\n"
-      "    Attributes:\n"
-      "      - Attribute:       DW_AT_language\n"
-      "        Form:            DW_FORM_data2\n"
-      "  - Code:            0x00000002\n"
-      "    Tag:             DW_TAG_base_type\n"
-      "    Children:        DW_CHILDREN_no\n"
-      "    Attributes:\n"
-      "      - Attribute:       DW_AT_encoding\n"
-      "        Form:            DW_FORM_data1\n"
-      "      - Attribute:       DW_AT_byte_size\n"
-      "        Form:            DW_FORM_data1\n"
+      "  - Table:\n"
+      "      - Code:            0x00000001\n"
+      "        Tag:             DW_TAG_compile_unit\n"
+      "        Children:        DW_CHILDREN_yes\n"
+      "        Attributes:\n"
+      "          - Attribute:       DW_AT_language\n"
+      "            Form:            DW_FORM_data2\n"
+      "      - Code:            0x00000002\n"
+      "        Tag:             DW_TAG_base_type\n"
+      "        Children:        DW_CHILDREN_no\n"
+      "        Attributes:\n"
+      "          - Attribute:       DW_AT_encoding\n"
+      "            Form:            DW_FORM_data1\n"
+      "          - Attribute:       DW_AT_byte_size\n"
+      "            Form:            DW_FORM_data1\n"
       "debug_info:\n"
       "  - Version:         4\n"
       "    AbbrOffset:      0\n"
       "    AddrSize:        8\n"
       "    Entries:\n"
       "      - AbbrCode:        0x00000001\n"
       "        Values:\n"
       "          - Value:           0x000000000000000C\n"

lldb/unittests/Symbol/Inputs/inlined-functions.yaml

debug_str:
     - sum4
     - c
     - d
     - main
     - argc
     - argv
     - char
     - sum
-  debug_abbrev:    
+  debug_abbrev:
+    - Table:
         - Code:            0x00000001
           Tag:             DW_TAG_compile_unit
           Children:        DW_CHILDREN_yes
-      Attributes:      
+          Attributes:
             - Attribute:       DW_AT_producer
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_language
               Form:            DW_FORM_data2
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_stmt_list
               Form:            DW_FORM_sec_offset
             - Attribute:       DW_AT_comp_dir
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_low_pc
               Form:            DW_FORM_addr
             - Attribute:       DW_AT_high_pc
               Form:            DW_FORM_data4
         - Code:            0x00000002
           Tag:             DW_TAG_subprogram
           Children:        DW_CHILDREN_yes
-      Attributes:      
+          Attributes:
             - Attribute:       DW_AT_low_pc
               Form:            DW_FORM_addr
             - Attribute:       DW_AT_high_pc
               Form:            DW_FORM_data4
             - Attribute:       DW_AT_frame_base
               Form:            DW_FORM_exprloc
             - Attribute:       DW_AT_linkage_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_decl_file
               Form:            DW_FORM_data1
             - Attribute:       DW_AT_decl_line
               Form:            DW_FORM_data1
             - Attribute:       DW_AT_type
               Form:            DW_FORM_ref4
             - Attribute:       DW_AT_external
               Form:            DW_FORM_flag_present
         - Code:            0x00000003
           Tag:             DW_TAG_formal_parameter
           Children:        DW_CHILDREN_no
-      Attributes:      
+          Attributes:
             - Attribute:       DW_AT_location
               Form:            DW_FORM_exprloc
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_decl_file
               Form:            DW_FORM_data1
             - Attribute:       DW_AT_decl_line
               Form:            DW_FORM_data1
             - Attribute:       DW_AT_type
               Form:            DW_FORM_ref4
         - Code:            0x00000004
           Tag:             DW_TAG_variable
           Children:        DW_CHILDREN_no
-      Attributes:      
+          Attributes:
             - Attribute:       DW_AT_location
               Form:            DW_FORM_exprloc
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_decl_file
               Form:            DW_FORM_data1
             - Attribute:       DW_AT_decl_line
               Form:            DW_FORM_data1
             - Attribute:       DW_AT_type
               Form:            DW_FORM_ref4
         - Code:            0x00000005
           Tag:             DW_TAG_subprogram
           Children:        DW_CHILDREN_yes
-      Attributes:      
+          Attributes:
             - Attribute:       DW_AT_linkage_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_decl_file
               Form:            DW_FORM_data1
             - Attribute:       DW_AT_decl_line
               Form:            DW_FORM_data1
             - Attribute:       DW_AT_type
               Form:            DW_FORM_ref4
             - Attribute:       DW_AT_external
               Form:            DW_FORM_flag_present
             - Attribute:       DW_AT_inline
               Form:            DW_FORM_data1
         - Code:            0x00000006
           Tag:             DW_TAG_formal_parameter
           Children:        DW_CHILDREN_no
-      Attributes:      
+          Attributes:
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_decl_file
               Form:            DW_FORM_data1
             - Attribute:       DW_AT_decl_line
               Form:            DW_FORM_data1
             - Attribute:       DW_AT_type
               Form:            DW_FORM_ref4
         - Code:            0x00000007
           Tag:             DW_TAG_variable
           Children:        DW_CHILDREN_no
-      Attributes:      
+          Attributes:
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_decl_file
               Form:            DW_FORM_data1
             - Attribute:       DW_AT_decl_line
               Form:            DW_FORM_data1
             - Attribute:       DW_AT_type
               Form:            DW_FORM_ref4
         - Code:            0x00000008
           Tag:             DW_TAG_base_type
           Children:        DW_CHILDREN_no
-      Attributes:      
+          Attributes:
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_encoding
               Form:            DW_FORM_data1
             - Attribute:       DW_AT_byte_size
               Form:            DW_FORM_data1
         - Code:            0x00000009
           Tag:             DW_TAG_subprogram
           Children:        DW_CHILDREN_yes
-      Attributes:      
+          Attributes:
             - Attribute:       DW_AT_low_pc
               Form:            DW_FORM_addr
             - Attribute:       DW_AT_high_pc
               Form:            DW_FORM_data4
             - Attribute:       DW_AT_frame_base
               Form:            DW_FORM_exprloc
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_decl_file
               Form:            DW_FORM_data1
             - Attribute:       DW_AT_decl_line
               Form:            DW_FORM_data1
             - Attribute:       DW_AT_type
               Form:            DW_FORM_ref4
             - Attribute:       DW_AT_external
               Form:            DW_FORM_flag_present
         - Code:            0x0000000A
           Tag:             DW_TAG_inlined_subroutine
           Children:        DW_CHILDREN_yes
-      Attributes:      
+          Attributes:
             - Attribute:       DW_AT_abstract_origin
               Form:            DW_FORM_ref4
             - Attribute:       DW_AT_low_pc
               Form:            DW_FORM_addr
             - Attribute:       DW_AT_high_pc
               Form:            DW_FORM_data4
             - Attribute:       DW_AT_call_file
               Form:            DW_FORM_data1
             - Attribute:       DW_AT_call_line
               Form:            DW_FORM_data1
         - Code:            0x0000000B
           Tag:             DW_TAG_formal_parameter
           Children:        DW_CHILDREN_no
-      Attributes:      
+          Attributes:
             - Attribute:       DW_AT_location
               Form:            DW_FORM_exprloc
             - Attribute:       DW_AT_abstract_origin
               Form:            DW_FORM_ref4
         - Code:            0x0000000C
           Tag:             DW_TAG_variable
           Children:        DW_CHILDREN_no
-      Attributes:      
+          Attributes:
             - Attribute:       DW_AT_location
               Form:            DW_FORM_exprloc
             - Attribute:       DW_AT_abstract_origin
               Form:            DW_FORM_ref4
         - Code:            0x0000000D
           Tag:             DW_TAG_pointer_type
           Children:        DW_CHILDREN_no
-      Attributes:      
+          Attributes:
             - Attribute:       DW_AT_type
               Form:            DW_FORM_ref4
   debug_info:      
     - Length:          579
       Version:         4
       AbbrOffset:      0
       AddrSize:        8
       Entries:         
         - AbbrCode:        0x00000001
           Values:          
             - Value:           0x0000000000000000
             - Value:           0x0000000000000004
             - Value:           0x000000000000002E
             - Value:           0x0000000000000000
             - Value:           0x0000000000000044
             - Value:           0x0000000000000000
             - Value:           0x00000000000000E0

lldb/unittests/SymbolFile/DWARF/DWARFASTParserClangTests.cpp

 //===-- DWARFASTParserClangTests.cpp --------------------------------------===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
 
 #include "Plugins/SymbolFile/DWARF/DWARFASTParserClang.h"
 #include "Plugins/SymbolFile/DWARF/DWARFCompileUnit.h"
 #include "Plugins/SymbolFile/DWARF/DWARFDIE.h"
 #include "TestingSupport/Symbol/YAMLModuleTester.h"
 #include "gmock/gmock.h"
 #include "gtest/gtest.h"
 
 using namespace lldb;
 using namespace lldb_private;

 // If your implementation needs to dereference the dummy pointers we are
 // defining here, causing this test to fail, feel free to delete it.
 TEST_F(DWARFASTParserClangTests,
        EnsureAllDIEsInDeclContextHaveBeenParsedParsesOnlyMatchingEntries) {
 
   /// Auxiliary debug info.
   const char *yamldata =
       "debug_abbrev:\n"
-      "  - Code:            0x00000001\n"
-      "    Tag:             DW_TAG_compile_unit\n"
-      "    Children:        DW_CHILDREN_yes\n"
-      "    Attributes:\n"
-      "      - Attribute:       DW_AT_language\n"
-      "        Form:            DW_FORM_data2\n"
-      "  - Code:            0x00000002\n"
-      "    Tag:             DW_TAG_base_type\n"
-      "    Children:        DW_CHILDREN_no\n"
-      "    Attributes:\n"
-      "      - Attribute:       DW_AT_encoding\n"
-      "        Form:            DW_FORM_data1\n"
-      "      - Attribute:       DW_AT_byte_size\n"
-      "        Form:            DW_FORM_data1\n"
+      "  - Table:\n"
+      "      - Code:            0x00000001\n"
+      "        Tag:             DW_TAG_compile_unit\n"
+      "        Children:        DW_CHILDREN_yes\n"
+      "        Attributes:\n"
+      "          - Attribute:       DW_AT_language\n"
+      "            Form:            DW_FORM_data2\n"
+      "      - Code:            0x00000002\n"
+      "        Tag:             DW_TAG_base_type\n"
+      "        Children:        DW_CHILDREN_no\n"
+      "        Attributes:\n"
+      "          - Attribute:       DW_AT_encoding\n"
+      "            Form:            DW_FORM_data1\n"
+      "          - Attribute:       DW_AT_byte_size\n"
+      "            Form:            DW_FORM_data1\n"
       "debug_info:\n"
       "  - Version:         4\n"
       "    AbbrOffset:      0\n"
       "    AddrSize:        8\n"
       "    Entries:\n"
       "      - AbbrCode:        0x00000001\n"
       "        Values:\n"
       "          - Value:           0x000000000000000C\n"

lldb/unittests/SymbolFile/DWARF/XcodeSDKModuleTests.cpp

 //===-- XcodeSDKModuleTests.cpp -------------------------------------------===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
 
 #include "Plugins/Platform/MacOSX/PlatformMacOSX.h"
 #include "Plugins/SymbolFile/DWARF/DWARFCompileUnit.h"
 #include "Plugins/SymbolFile/DWARF/DWARFDIE.h"
 #include "Plugins/TypeSystem/Clang/TypeSystemClang.h"
 #include "TestingSupport/Symbol/YAMLModuleTester.h"
 #include "lldb/Core/PluginManager.h"
 #include "gmock/gmock.h"
 #include "gtest/gtest.h"
 

 } // namespace
 
 
 TEST_F(XcodeSDKModuleTests, TestModuleGetXcodeSDK) {
   const char *yamldata = R"(
 debug_str:
   - MacOSX10.9.sdk
 debug_abbrev:
+  - Table:
       - Code:            0x00000001
         Tag:             DW_TAG_compile_unit
         Children:        DW_CHILDREN_no
         Attributes:
           - Attribute:       DW_AT_language
             Form:            DW_FORM_data2
           - Attribute:       DW_AT_APPLE_sdk
             Form:            DW_FORM_strp
 debug_info:
   - Length:          8
     Version:         2
     AbbrOffset:      0
     AddrSize:        8
     Entries:
       - AbbrCode:        0x00000001
         Values:

llvm/include/llvm/ObjectYAML/DWARFEmitter.h

 #ifndef LLVM_OBJECTYAML_DWARFEMITTER_H
 #define LLVM_OBJECTYAML_DWARFEMITTER_H
 
 #include "llvm/ADT/StringMap.h"
 #include "llvm/ADT/StringRef.h"
 #include "llvm/Support/Error.h"
 #include "llvm/Support/Host.h"
 #include "llvm/Support/MemoryBuffer.h"
+#include <map>
 #include <memory>
 
 namespace llvm {
 
 class raw_ostream;
 
 namespace DWARFYAML {
 
 struct Data;
 struct PubSection;
 
-Error emitDebugAbbrev(raw_ostream &OS, const Data &DI);
-Error emitDebugStr(raw_ostream &OS, const Data &DI);
+class DWARFState {
+private:
+  Data &DWARF;
+  std::map<uint64_t, uint64_t> AbbrevID2Index;
+
+  DWARFState(Data &DI, Error &Err);
+
+public:
+  static Expected<DWARFState> create(Data &DI);
+  Data &getDWARFData() const { return DWARF; }
+  Optional<uint64_t> getAbbrevTableIndexByID(uint64_t ID) const;
+};
+
+Error emitDebugAbbrev(raw_ostream &OS, const DWARFState &DS);
+Error emitDebugStr(raw_ostream &OS, const DWARFState &DS);
+Error emitDebugAranges(raw_ostream &OS, const DWARFState &DS);
+Error emitDebugRanges(raw_ostream &OS, const DWARFState &DS);
+Error emitDebugPubnames(raw_ostream &OS, const DWARFState &DS);
+Error emitDebugPubtypes(raw_ostream &OS, const DWARFState &DS);
+Error emitDebugGNUPubnames(raw_ostream &OS, const DWARFState &DS);
+Error emitDebugGNUPubtypes(raw_ostream &OS, const DWARFState &DS);
+Error emitDebugInfo(raw_ostream &OS, const DWARFState &DS);
+Error emitDebugLine(raw_ostream &OS, const DWARFState &DS);
+Error emitDebugAddr(raw_ostream &OS, const DWARFState &DS);
+Error emitDebugStrOffsets(raw_ostream &OS, const DWARFState &DS);
+Error emitDebugRnglists(raw_ostream &OS, const DWARFState &DS);
+Error emitDebugLoclists(raw_ostream &OS, const DWARFState &DS);
 
-Error emitDebugAranges(raw_ostream &OS, const Data &DI);
-Error emitDebugRanges(raw_ostream &OS, const Data &DI);
-Error emitDebugPubnames(raw_ostream &OS, const Data &DI);
-Error emitDebugPubtypes(raw_ostream &OS, const Data &DI);
-Error emitDebugGNUPubnames(raw_ostream &OS, const Data &DI);
-Error emitDebugGNUPubtypes(raw_ostream &OS, const Data &DI);
-Error emitDebugInfo(raw_ostream &OS, const Data &DI);
-Error emitDebugLine(raw_ostream &OS, const Data &DI);
-Error emitDebugAddr(raw_ostream &OS, const Data &DI);
-Error emitDebugStrOffsets(raw_ostream &OS, const Data &DI);
-Error emitDebugRnglists(raw_ostream &OS, const Data &DI);
-Error emitDebugLoclists(raw_ostream &OS, const Data &DI);
-
-std::function<Error(raw_ostream &, const Data &)>
+std::function<Error(raw_ostream &, const DWARFState &)>
 getDWARFEmitterByName(StringRef SecName);
 Expected<StringMap<std::unique_ptr<MemoryBuffer>>>
 emitDebugSections(StringRef YAMLString,
                   bool IsLittleEndian = sys::IsLittleEndianHost,
                   bool Is64BitAddrSize = true);
 } // end namespace DWARFYAML
 } // end namespace llvm
 
 #endif // LLVM_OBJECTYAML_DWARFEMITTER_H

llvm/include/llvm/ObjectYAML/DWARFYAML.h

 
 struct Abbrev {
   Optional<yaml::Hex64> Code;
   llvm::dwarf::Tag Tag;
   llvm::dwarf::Constants Children;
   std::vector<AttributeAbbrev> Attributes;
 };
 
+struct AbbrevTable {
+  Optional<uint64_t> ID;
+  std::vector<Abbrev> Table;
+};
+
 struct ARangeDescriptor {
   llvm::yaml::Hex64 Address;
   yaml::Hex64 Length;
 };
 
 struct ARange {
   dwarf::DwarfFormat Format;
   Optional<yaml::Hex64> Length;

 };
 
 struct Unit {
   dwarf::DwarfFormat Format;
   Optional<yaml::Hex64> Length;
   uint16_t Version;
   Optional<uint8_t> AddrSize;
   llvm::dwarf::UnitType Type; // Added in DWARF 5
+  Optional<uint64_t> AbbrevTableID;
   yaml::Hex64 AbbrOffset;
   std::vector<Entry> Entries;
 };
 
 struct File {
   StringRef Name;
   uint64_t DirIdx;
   uint64_t ModTime;
template <typename EntryType> struct ListTable {
   Optional<uint32_t> OffsetEntryCount;
   Optional<std::vector<yaml::Hex64>> Offsets;
   std::vector<ListEntries<EntryType>> Lists;
 };
 
 struct Data {
   bool IsLittleEndian;
   bool Is64BitAddrSize;
-  std::vector<Abbrev> AbbrevDecls;
+  std::vector<AbbrevTable> DebugAbbrev;
   std::vector<StringRef> DebugStrings;
   Optional<std::vector<StringOffsetsTable>> DebugStrOffsets;
   Optional<std::vector<ARange>> DebugAranges;
   std::vector<Ranges> DebugRanges;
   std::vector<AddrTableEntry> DebugAddr;
   Optional<PubSection> PubNames;
   Optional<PubSection> PubTypes;
 
   Optional<PubSection> GNUPubNames;
   Optional<PubSection> GNUPubTypes;
 
   std::vector<Unit> CompileUnits;
 
   std::vector<LineTable> DebugLines;
   Optional<std::vector<ListTable<RnglistEntry>>> DebugRnglists;
   Optional<std::vector<ListTable<LoclistEntry>>> DebugLoclists;
 
   bool isEmpty() const;
 
   SetVector<StringRef> getNonEmptySectionNames() const;
 };
 
 } // end namespace DWARFYAML
 } // end namespace llvm
 
 LLVM_YAML_IS_SEQUENCE_VECTOR(llvm::DWARFYAML::AttributeAbbrev)
 LLVM_YAML_IS_SEQUENCE_VECTOR(llvm::DWARFYAML::Abbrev)
+LLVM_YAML_IS_SEQUENCE_VECTOR(llvm::DWARFYAML::AbbrevTable)
 LLVM_YAML_IS_SEQUENCE_VECTOR(llvm::DWARFYAML::ARangeDescriptor)
 LLVM_YAML_IS_SEQUENCE_VECTOR(llvm::DWARFYAML::ARange)
 LLVM_YAML_IS_SEQUENCE_VECTOR(llvm::DWARFYAML::RangeEntry)
 LLVM_YAML_IS_SEQUENCE_VECTOR(llvm::DWARFYAML::Ranges)
 LLVM_YAML_IS_SEQUENCE_VECTOR(llvm::DWARFYAML::PubEntry)
 LLVM_YAML_IS_SEQUENCE_VECTOR(llvm::DWARFYAML::Unit)
 LLVM_YAML_IS_SEQUENCE_VECTOR(llvm::DWARFYAML::FormValue)
 LLVM_YAML_IS_SEQUENCE_VECTOR(llvm::DWARFYAML::Entry)

 
 namespace llvm {
 namespace yaml {
 
 template <> struct MappingTraits<DWARFYAML::Data> {
   static void mapping(IO &IO, DWARFYAML::Data &DWARF);
 };
 
+template <> struct MappingTraits<DWARFYAML::AbbrevTable> {
+  static void mapping(IO &IO, DWARFYAML::AbbrevTable &AbbrevTable);
+};
+
 template <> struct MappingTraits<DWARFYAML::Abbrev> {
   static void mapping(IO &IO, DWARFYAML::Abbrev &Abbrev);
 };
 
 template <> struct MappingTraits<DWARFYAML::AttributeAbbrev> {
   static void mapping(IO &IO, DWARFYAML::AttributeAbbrev &AttAbbrev);
 };
 

llvm/lib/ObjectYAML/DWARFEmitter.cpp

 //===- DWARFEmitter - Convert YAML to DWARF binary data -------------------===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
 ///
 /// \file
 /// The DWARF component of yaml2obj. Provided as library code for tests.
 ///
 //===----------------------------------------------------------------------===//
 
 #include "llvm/ObjectYAML/DWARFEmitter.h"
 #include "llvm/ADT/ArrayRef.h"
+#include "llvm/ADT/StringExtras.h"
 #include "llvm/ADT/StringMap.h"
 #include "llvm/ADT/StringRef.h"
 #include "llvm/ADT/StringSwitch.h"
 #include "llvm/BinaryFormat/Dwarf.h"
 #include "llvm/ObjectYAML/DWARFYAML.h"
 #include "llvm/Support/Errc.h"
 #include "llvm/Support/Error.h"
 #include "llvm/Support/Host.h"

 }
 
 static void writeDWARFOffset(uint64_t Offset, dwarf::DwarfFormat Format,
                              raw_ostream &OS, bool IsLittleEndian) {
   cantFail(writeVariableSizedInteger(Offset, Format == dwarf::DWARF64 ? 8 : 4,
                                      OS, IsLittleEndian));
 }
 
-Error DWARFYAML::emitDebugStr(raw_ostream &OS, const DWARFYAML::Data &DI) {
+DWARFYAML::DWARFState::DWARFState(DWARFYAML::Data &DI, Error &Err) : DWARF(DI) {
+  ErrorAsOutParameter EAO(&Err);
+
+  for (uint64_t I = 0; I < DI.DebugAbbrev.size(); ++I) {
+    // If the abbrev table's ID isn't specified, we use the index as its ID.
+    uint64_t ID = I;
+    if (DI.DebugAbbrev[I].ID)
+      ID = *DI.DebugAbbrev[I].ID;
+
+    if (AbbrevID2Index.count(ID)) {
+      Err = createStringError(errc::invalid_argument,
+                              "the ID (%" PRIu64
+                              ") of abbrev table with index %" PRIu64
+                              " has been used",
+                              ID, I);
+      return;
+    }
+    AbbrevID2Index.insert({ID, I});
+  }
+}
+
+Optional<uint64_t>
+DWARFYAML::DWARFState::getAbbrevTableIndexByID(uint64_t ID) const {
+  auto It = AbbrevID2Index.find(ID);
+  if (It == AbbrevID2Index.end())
+    return None;
+  return It->second;
+}
+
+Expected<DWARFYAML::DWARFState>
+DWARFYAML::DWARFState::create(DWARFYAML::Data &DI) {
+  Error Err = Error::success();
+  DWARFState DS(DI, Err);
+  if (Err)
+    return std::move(Err);
+  return std::move(DS);
+}
+
+Error DWARFYAML::emitDebugStr(raw_ostream &OS,
+                              const DWARFState &DS) {
+  const DWARFYAML::Data &DI = DS.getDWARFData();
   for (auto Str : DI.DebugStrings) {
     OS.write(Str.data(), Str.size());
     OS.write('\0');
   }
 
   return Error::success();
 }
 
-Error DWARFYAML::emitDebugAbbrev(raw_ostream &OS, const DWARFYAML::Data &DI) {
+Error DWARFYAML::emitDebugAbbrev(raw_ostream &OS,
+                                 const DWARFState &DS) {
+  const DWARFYAML::Data &DI = DS.getDWARFData();
+  for (const DWARFYAML::AbbrevTable &AbbrevTable : DI.DebugAbbrev) {
     uint64_t AbbrevCode = 0;
-  for (auto AbbrevDecl : DI.AbbrevDecls) {
-    AbbrevCode = AbbrevDecl.Code ? (uint64_t)*AbbrevDecl.Code : AbbrevCode + 1;
+    for (auto AbbrevDecl : AbbrevTable.Table) {
+      AbbrevCode =
+          AbbrevDecl.Code ? (uint64_t)*AbbrevDecl.Code : AbbrevCode + 1;
       encodeULEB128(AbbrevCode, OS);
       encodeULEB128(AbbrevDecl.Tag, OS);
       OS.write(AbbrevDecl.Children);
       for (auto Attr : AbbrevDecl.Attributes) {
         encodeULEB128(Attr.Attribute, OS);
         encodeULEB128(Attr.Form, OS);
         if (Attr.Form == dwarf::DW_FORM_implicit_const)
           encodeSLEB128(Attr.Value, OS);
       }
       encodeULEB128(0, OS);
       encodeULEB128(0, OS);
     }
 
-  // The abbreviations for a given compilation unit end with an entry consisting
-  // of a 0 byte for the abbreviation code.
+    // The abbreviations for a given compilation unit end with an entry
+    // consisting of a 0 byte for the abbreviation code.
     OS.write_zeros(1);
+  }
 
   return Error::success();
 }
 
-Error DWARFYAML::emitDebugAranges(raw_ostream &OS, const DWARFYAML::Data &DI) {
+Error DWARFYAML::emitDebugAranges(raw_ostream &OS,
+                                  const DWARFState &DS) {
+  const DWARFYAML::Data &DI = DS.getDWARFData();
   assert(DI.DebugAranges && "unexpected emitDebugAranges() call");
   for (auto Range : *DI.DebugAranges) {
     uint8_t AddrSize;
     if (Range.AddrSize)
       AddrSize = *Range.AddrSize;
     else
       AddrSize = DI.Is64BitAddrSize ? 8 : 4;
 
for (auto Descriptor : Range.Descriptors) {
                                          DI.IsLittleEndian));
     }
     ZeroFillBytes(OS, AddrSize * 2);
   }
 
   return Error::success();
 }
 
-Error DWARFYAML::emitDebugRanges(raw_ostream &OS, const DWARFYAML::Data &DI) {
+Error DWARFYAML::emitDebugRanges(raw_ostream &OS,
+                                 const DWARFState &DS) {
+  const DWARFYAML::Data &DI = DS.getDWARFData();
   const size_t RangesOffset = OS.tell();
   uint64_t EntryIndex = 0;
   for (auto DebugRanges : DI.DebugRanges) {
     const size_t CurrOffset = OS.tell() - RangesOffset;
     if (DebugRanges.Offset && (uint64_t)*DebugRanges.Offset < CurrOffset)
       return createStringError(errc::invalid_argument,
                                "'Offset' for 'debug_ranges' with index " +
                                    Twine(EntryIndex) +
if (IsGNUPubSec)
       writeInteger((uint8_t)Entry.Descriptor, OS, IsLittleEndian);
     OS.write(Entry.Name.data(), Entry.Name.size());
     OS.write('\0');
   }
 
   return Error::success();
 }
 
-Error DWARFYAML::emitDebugPubnames(raw_ostream &OS, const Data &DI) {
+Error DWARFYAML::emitDebugPubnames(raw_ostream &OS,
+                                   const DWARFState &DS) {
+  const DWARFYAML::Data &DI = DS.getDWARFData();
   assert(DI.PubNames && "unexpected emitDebugPubnames() call");
   return emitPubSection(OS, *DI.PubNames, DI.IsLittleEndian);
 }
 
-Error DWARFYAML::emitDebugPubtypes(raw_ostream &OS, const Data &DI) {
+Error DWARFYAML::emitDebugPubtypes(raw_ostream &OS,
+                                   const DWARFState &DS) {
+  const DWARFYAML::Data &DI = DS.getDWARFData();
   assert(DI.PubTypes && "unexpected emitDebugPubtypes() call");
   return emitPubSection(OS, *DI.PubTypes, DI.IsLittleEndian);
 }
 
-Error DWARFYAML::emitDebugGNUPubnames(raw_ostream &OS, const Data &DI) {
+Error DWARFYAML::emitDebugGNUPubnames(raw_ostream &OS,
+                                      const DWARFState &DS) {
+  const DWARFYAML::Data &DI = DS.getDWARFData();
   assert(DI.GNUPubNames && "unexpected emitDebugGNUPubnames() call");
   return emitPubSection(OS, *DI.GNUPubNames, DI.IsLittleEndian,
                         /*IsGNUStyle=*/true);
 }
 
-Error DWARFYAML::emitDebugGNUPubtypes(raw_ostream &OS, const Data &DI) {
+Error DWARFYAML::emitDebugGNUPubtypes(raw_ostream &OS,
+                                      const DWARFState &DS) {
+  const DWARFYAML::Data &DI = DS.getDWARFData();
   assert(DI.GNUPubTypes && "unexpected emitDebugGNUPubtypes() call");
   return emitPubSection(OS, *DI.GNUPubTypes, DI.IsLittleEndian,
                         /*IsGNUStyle=*/true);
 }
 
-static Expected<uint64_t> writeDIE(ArrayRef<DWARFYAML::Abbrev> AbbrevDecls,
+static Expected<uint64_t> writeDIE(const DWARFYAML::DWARFState &DS,
+                                   uint64_t AbbrevTableID,
                                    const dwarf::FormParams &Params,
                                    const DWARFYAML::Entry &Entry,
                                    raw_ostream &OS, bool IsLittleEndian) {
   uint64_t EntryBegin = OS.tell();
   encodeULEB128(Entry.AbbrCode, OS);
   uint32_t AbbrCode = Entry.AbbrCode;
   if (AbbrCode == 0 || Entry.Values.empty())
     return OS.tell() - EntryBegin;
 
+  Optional<uint64_t> AbbrevTableIndex =
+      DS.getAbbrevTableIndexByID(AbbrevTableID);
+  if (!AbbrevTableIndex)
+    return createStringError(errc::invalid_argument,
+                             "cannot find abbrev table whose ID is " +
+                                 utostr(AbbrevTableID));
+  ArrayRef<DWARFYAML::Abbrev> AbbrevDecls(
+      DS.getDWARFData().DebugAbbrev[*AbbrevTableIndex].Table);
+
   if (AbbrCode > AbbrevDecls.size())
     return createStringError(
         errc::invalid_argument,
         "abbrev code must be less than or equal to the number of "
         "entries in abbreviation table");
   const DWARFYAML::Abbrev &Abbrev = AbbrevDecls[AbbrCode - 1];
   auto FormVal = Entry.Values.begin();
   auto AbbrForm = Abbrev.Attributes.begin();
do {
         break;
       }
     } while (Indirect);
   }
 
   return OS.tell() - EntryBegin;
 }
 
-Error DWARFYAML::emitDebugInfo(raw_ostream &OS, const DWARFYAML::Data &DI) {
-  for (const DWARFYAML::Unit &Unit : DI.CompileUnits) {
+Error DWARFYAML::emitDebugInfo(raw_ostream &OS,
+                               const DWARFState &DS) {
+  const DWARFYAML::Data &DI = DS.getDWARFData();
+  for (uint64_t I = 0; I < DI.CompileUnits.size(); ++ I) {
+    const DWARFYAML::Unit &Unit = DI.CompileUnits[I];
     uint8_t AddrSize;
     if (Unit.AddrSize)
       AddrSize = *Unit.AddrSize;
     else
       AddrSize = DI.Is64BitAddrSize ? 8 : 4;
     dwarf::FormParams Params = {Unit.Version, AddrSize, Unit.Format};
     uint64_t Length = 3; // sizeof(version) + sizeof(address_size)
     Length += Unit.Version >= 5 ? 1 : 0;       // sizeof(unit_type)
     Length += Params.getDwarfOffsetByteSize(); // sizeof(debug_abbrev_offset)
 
     // Since the length of the current compilation unit is undetermined yet, we
     // firstly write the content of the compilation unit to a buffer to
     // calculate it and then serialize the buffer content to the actual output
     // stream.
     std::string EntryBuffer;
     raw_string_ostream EntryBufferOS(EntryBuffer);
 
+    // If the abbrev table's ID isn't specified, we use the compilation unit's
+    // index as the ID.
+    uint64_t AbbrevTableID = I;
+    if (Unit.AbbrevTableID)
+      AbbrevTableID = *Unit.AbbrevTableID;
+
     for (const DWARFYAML::Entry &Entry : Unit.Entries) {
-      if (Expected<uint64_t> EntryLength = writeDIE(
-              DI.AbbrevDecls, Params, Entry, EntryBufferOS, DI.IsLittleEndian))
+      if (Expected<uint64_t> EntryLength =
+              writeDIE(DS, AbbrevTableID, Params, Entry, EntryBufferOS,
+                       DI.IsLittleEndian))
         Length += *EntryLength;
       else
         return EntryLength.takeError();
     }
 
     // If the length is specified in the YAML description, we use it instead of
     // the actual length.
     if (Unit.Length)

 static void emitFileEntry(raw_ostream &OS, const DWARFYAML::File &File) {
   OS.write(File.Name.data(), File.Name.size());
   OS.write('\0');
   encodeULEB128(File.DirIdx, OS);
   encodeULEB128(File.ModTime, OS);
   encodeULEB128(File.Length, OS);
 }
 
-Error DWARFYAML::emitDebugLine(raw_ostream &OS, const DWARFYAML::Data &DI) {
+Error DWARFYAML::emitDebugLine(raw_ostream &OS,
+                               const DWARFState &DS) {
+  const DWARFYAML::Data &DI = DS.getDWARFData();
   for (const auto &LineTable : DI.DebugLines) {
     writeInitialLength(LineTable.Format, LineTable.Length, OS,
                        DI.IsLittleEndian);
     uint64_t SizeOfPrologueLength = LineTable.Format == dwarf::DWARF64 ? 8 : 4;
     writeInteger((uint16_t)LineTable.Version, OS, DI.IsLittleEndian);
     cantFail(writeVariableSizedInteger(
         LineTable.PrologueLength, SizeOfPrologueLength, OS, DI.IsLittleEndian));
     writeInteger((uint8_t)LineTable.MinInstLength, OS, DI.IsLittleEndian);
for (auto Op : LineTable.Opcodes) {
         }
       }
     }
   }
 
   return Error::success();
 }
 
-Error DWARFYAML::emitDebugAddr(raw_ostream &OS, const Data &DI) {
+Error DWARFYAML::emitDebugAddr(raw_ostream &OS,
+                               const DWARFState &DS) {
+  const DWARFYAML::Data &DI = DS.getDWARFData();
   for (const AddrTableEntry &TableEntry : DI.DebugAddr) {
     uint8_t AddrSize;
     if (TableEntry.AddrSize)
       AddrSize = *TableEntry.AddrSize;
     else
       AddrSize = DI.Is64BitAddrSize ? 8 : 4;
 
     uint64_t Length;
for (const SegAddrPair &Pair : TableEntry.SegAddrPairs) {
                                    "unable to write debug_addr address: %s",
                                    toString(std::move(Err)).c_str());
     }
   }
 
   return Error::success();
 }
 
-Error DWARFYAML::emitDebugStrOffsets(raw_ostream &OS, const Data &DI) {
+Error DWARFYAML::emitDebugStrOffsets(raw_ostream &OS,
+                                     const DWARFState &DS) {
+  const DWARFYAML::Data &DI = DS.getDWARFData();
   assert(DI.DebugStrOffsets && "unexpected emitDebugStrOffsets() call");
   for (const DWARFYAML::StringOffsetsTable &Table : *DI.DebugStrOffsets) {
     uint64_t Length;
     if (Table.Length)
       Length = *Table.Length;
     else
       // sizeof(version) + sizeof(padding) = 4
       Length =
else if (OffsetEntryCount != 0)
       EmitOffsets(Offsets, OffsetsSize);
 
     OS.write(ListBuffer.data(), ListBuffer.size());
   }
 
   return Error::success();
 }
 
-Error DWARFYAML::emitDebugRnglists(raw_ostream &OS, const Data &DI) {
+Error DWARFYAML::emitDebugRnglists(raw_ostream &OS,
+                                   const DWARFState &DS) {
+  const DWARFYAML::Data &DI = DS.getDWARFData();
   assert(DI.DebugRnglists && "unexpected emitDebugRnglists() call");
   return writeDWARFLists<DWARFYAML::RnglistEntry>(
       OS, *DI.DebugRnglists, DI.IsLittleEndian, DI.Is64BitAddrSize);
 }
 
-Error DWARFYAML::emitDebugLoclists(raw_ostream &OS, const Data &DI) {
+Error DWARFYAML::emitDebugLoclists(raw_ostream &OS,
+                                   const DWARFState &DS) {
+  const DWARFYAML::Data &DI = DS.getDWARFData();
   assert(DI.DebugLoclists && "unexpected emitDebugRnglists() call");
   return writeDWARFLists<DWARFYAML::LoclistEntry>(
       OS, *DI.DebugLoclists, DI.IsLittleEndian, DI.Is64BitAddrSize);
 }
 
-std::function<Error(raw_ostream &, const DWARFYAML::Data &)>
+std::function<Error(raw_ostream &, const DWARFYAML::DWARFState &)>
 DWARFYAML::getDWARFEmitterByName(StringRef SecName) {
   auto EmitFunc =
       StringSwitch<
-          std::function<Error(raw_ostream &, const DWARFYAML::Data &)>>(SecName)
+          std::function<Error(raw_ostream &, const DWARFYAML::DWARFState &)>>(
+          SecName)
           .Case("debug_abbrev", DWARFYAML::emitDebugAbbrev)
           .Case("debug_addr", DWARFYAML::emitDebugAddr)
           .Case("debug_aranges", DWARFYAML::emitDebugAranges)
           .Case("debug_gnu_pubnames", DWARFYAML::emitDebugGNUPubnames)
           .Case("debug_gnu_pubtypes", DWARFYAML::emitDebugGNUPubtypes)
           .Case("debug_info", DWARFYAML::emitDebugInfo)
           .Case("debug_line", DWARFYAML::emitDebugLine)
           .Case("debug_loclists", DWARFYAML::emitDebugLoclists)
           .Case("debug_pubnames", DWARFYAML::emitDebugPubnames)
           .Case("debug_pubtypes", DWARFYAML::emitDebugPubtypes)
           .Case("debug_ranges", DWARFYAML::emitDebugRanges)
           .Case("debug_rnglists", DWARFYAML::emitDebugRnglists)
           .Case("debug_str", DWARFYAML::emitDebugStr)
           .Case("debug_str_offsets", DWARFYAML::emitDebugStrOffsets)
-          .Default([&](raw_ostream &, const DWARFYAML::Data &) {
+          .Default([&](raw_ostream &, const DWARFYAML::DWARFState &) {
             return createStringError(errc::not_supported,
                                      SecName + " is not supported");
           });
 
   return EmitFunc;
 }
 
 static Error
-emitDebugSectionImpl(const DWARFYAML::Data &DI, StringRef Sec,
+emitDebugSectionImpl(const DWARFYAML::DWARFState &DS, StringRef Sec,
                      StringMap<std::unique_ptr<MemoryBuffer>> &OutputBuffers) {
   std::string Data;
   raw_string_ostream DebugInfoStream(Data);
 
   auto EmitFunc = DWARFYAML::getDWARFEmitterByName(Sec);
 
-  if (Error Err = EmitFunc(DebugInfoStream, DI))
+  if (Error Err = EmitFunc(DebugInfoStream, DS))
     return Err;
   DebugInfoStream.flush();
   if (!Data.empty())
     OutputBuffers[Sec] = MemoryBuffer::getMemBufferCopy(Data);
 
   return Error::success();
 }
 
DWARFYAML::emitDebugSections(StringRef YAMLString, bool IsLittleEndian,
   YIn >> DI;
   if (YIn.error())
     return createStringError(YIn.error(), GeneratedDiag.getMessage());
 
   StringMap<std::unique_ptr<MemoryBuffer>> DebugSections;
   Error Err = Error::success();
   cantFail(std::move(Err));
 
+  Expected<DWARFState> DSOrErr = DWARFState::create(DI);
+  if (!DSOrErr)
+    return DSOrErr.takeError();
+
   for (StringRef SecName : DI.getNonEmptySectionNames())
     Err = joinErrors(std::move(Err),
-                     emitDebugSectionImpl(DI, SecName, DebugSections));
+                     emitDebugSectionImpl(*DSOrErr, SecName, DebugSections));
 
   if (Err)
     return std::move(Err);
   return std::move(DebugSections);
 }

llvm/lib/ObjectYAML/DWARFYAML.cpp

SetVector<StringRef> DWARFYAML::Data::getNonEmptySectionNames() const {
   if (DebugAranges)
     SecNames.insert("debug_aranges");
   if (!DebugRanges.empty())
     SecNames.insert("debug_ranges");
   if (!DebugLines.empty())
     SecNames.insert("debug_line");
   if (!DebugAddr.empty())
     SecNames.insert("debug_addr");
-  if (!AbbrevDecls.empty())
+  if (!DebugAbbrev.empty())
     SecNames.insert("debug_abbrev");
   if (!CompileUnits.empty())
     SecNames.insert("debug_info");
   if (PubNames)
     SecNames.insert("debug_pubnames");
   if (PubTypes)
     SecNames.insert("debug_pubtypes");
   if (GNUPubNames)

 
 namespace yaml {
 
 void MappingTraits<DWARFYAML::Data>::mapping(IO &IO, DWARFYAML::Data &DWARF) {
   void *OldContext = IO.getContext();
   DWARFYAML::DWARFContext DWARFCtx;
   IO.setContext(&DWARFCtx);
   IO.mapOptional("debug_str", DWARF.DebugStrings);
-  IO.mapOptional("debug_abbrev", DWARF.AbbrevDecls);
+  IO.mapOptional("debug_abbrev", DWARF.DebugAbbrev);
   IO.mapOptional("debug_aranges", DWARF.DebugAranges);
   if (!DWARF.DebugRanges.empty() || !IO.outputting())
     IO.mapOptional("debug_ranges", DWARF.DebugRanges);
   IO.mapOptional("debug_pubnames", DWARF.PubNames);
   IO.mapOptional("debug_pubtypes", DWARF.PubTypes);
   DWARFCtx.IsGNUPubSec = true;
   IO.mapOptional("debug_gnu_pubnames", DWARF.GNUPubNames);
   IO.mapOptional("debug_gnu_pubtypes", DWARF.GNUPubTypes);
   IO.mapOptional("debug_info", DWARF.CompileUnits);
   IO.mapOptional("debug_line", DWARF.DebugLines);
   IO.mapOptional("debug_addr", DWARF.DebugAddr);
   IO.mapOptional("debug_str_offsets", DWARF.DebugStrOffsets);
   IO.mapOptional("debug_rnglists", DWARF.DebugRnglists);
   IO.mapOptional("debug_loclists", DWARF.DebugLoclists);
   IO.setContext(OldContext);
 }
 
+void MappingTraits<DWARFYAML::AbbrevTable>::mapping(
+    IO &IO, DWARFYAML::AbbrevTable &AbbrevTable) {
+  IO.mapOptional("ID", AbbrevTable.ID);
+  IO.mapOptional("Table", AbbrevTable.Table);
+}
+
 void MappingTraits<DWARFYAML::Abbrev>::mapping(IO &IO,
                                                DWARFYAML::Abbrev &Abbrev) {
   IO.mapOptional("Code", Abbrev.Code);
   IO.mapRequired("Tag", Abbrev.Tag);
   IO.mapRequired("Children", Abbrev.Children);
   IO.mapRequired("Attributes", Abbrev.Attributes);
 }
 

 }
 
 void MappingTraits<DWARFYAML::Unit>::mapping(IO &IO, DWARFYAML::Unit &Unit) {
   IO.mapOptional("Format", Unit.Format, dwarf::DWARF32);
   IO.mapOptional("Length", Unit.Length);
   IO.mapRequired("Version", Unit.Version);
   if (Unit.Version >= 5)
     IO.mapRequired("UnitType", Unit.Type);
+  IO.mapOptional("AbbrevTableID", Unit.AbbrevTableID);
   IO.mapRequired("AbbrOffset", Unit.AbbrOffset);
   IO.mapOptional("AddrSize", Unit.AddrSize);
   IO.mapOptional("Entries", Unit.Entries);
 }
 
 void MappingTraits<DWARFYAML::Entry>::mapping(IO &IO, DWARFYAML::Entry &Entry) {
   IO.mapRequired("AbbrCode", Entry.AbbrCode);
   IO.mapOptional("Values", Entry.Values);

llvm/lib/ObjectYAML/ELFEmitter.cpp

template <class ELFT> class ELFState {
 
   /// The future ".dynstr" section.
   StringTableBuilder DotDynstr{StringTableBuilder::ELF};
 
   NameToIdxMap SN2I;
   NameToIdxMap SymN2I;
   NameToIdxMap DynSymN2I;
   ELFYAML::Object &Doc;
+  Optional<DWARFYAML::DWARFState> DWARFState;
 
   StringSet<> ExcludedSectionHeaders;
 
   uint64_t LocationCounter = 0;
   bool HasError = false;
   yaml::ErrorHandler ErrHandler;
   void reportError(const Twine &Msg);
   void reportError(Error Err);
if (!DocSections.insert(C->Name).second)
                   "' at YAML section/fill number " + Twine(I));
   }
 
   std::vector<StringRef> ImplicitSections;
   if (Doc.DynamicSymbols)
     ImplicitSections.insert(ImplicitSections.end(), {".dynsym", ".dynstr"});
   if (Doc.Symbols)
     ImplicitSections.push_back(".symtab");
-  if (Doc.DWARF)
-    for (StringRef DebugSecName : Doc.DWARF->getNonEmptySectionNames()) {
+  if (Doc.DWARF) {
+    if (Expected<DWARFYAML::DWARFState> DSOrErr =
+        DWARFYAML::DWARFState::create(*Doc.DWARF)) {
+      DWARFState.emplace(*DSOrErr);
+      for (StringRef DebugSecName :
+           DWARFState->getDWARFData().getNonEmptySectionNames()) {
         std::string SecName = ("." + DebugSecName).str();
         ImplicitSections.push_back(StringRef(SecName).copy(StringAlloc));
       }
+    } else {
+      reportError(DSOrErr.takeError());
+    }
+  }
   ImplicitSections.insert(ImplicitSections.end(), {".strtab", ".shstrtab"});
 
   // Insert placeholders for implicit sections that are not
   // defined explicitly in YAML.
   for (StringRef SecName : ImplicitSections) {
     if (DocSections.count(SecName))
       continue;
 
void ELFState<ELFT>::initStrtabSectionHeader(Elf_Shdr &SHeader, StringRef Name,
   if (YAMLSec && YAMLSec->Flags)
     SHeader.sh_flags = *YAMLSec->Flags;
   else if (Name == ".dynstr")
     SHeader.sh_flags = ELF::SHF_ALLOC;
 
   assignSectionAddress(SHeader, YAMLSec);
 }
 
-static bool shouldEmitDWARF(DWARFYAML::Data &DWARF, StringRef Name) {
+static bool shouldEmitDWARF(const DWARFYAML::Data &DWARF, StringRef Name) {
   SetVector<StringRef> DebugSecNames = DWARF.getNonEmptySectionNames();
   return Name.consume_front(".") && DebugSecNames.count(Name);
 }
 
 template <class ELFT>
 Expected<uint64_t> emitDWARF(typename ELFT::Shdr &SHeader, StringRef Name,
-                             const DWARFYAML::Data &DWARF,
+                             const DWARFYAML::DWARFState &DS,
                              ContiguousBlobAccumulator &CBA) {
   // We are unable to predict the size of debug data, so we request to write 0
   // bytes. This should always return us an output stream unless CBA is already
   // in an error state.
   raw_ostream *OS = CBA.getRawOS(0);
   if (!OS)
     return 0;
 
   uint64_t BeginOffset = CBA.tell();
 
   auto EmitFunc = DWARFYAML::getDWARFEmitterByName(Name.substr(1));
-  if (Error Err = EmitFunc(*OS, DWARF))
+  if (Error Err = EmitFunc(*OS, DS))
     return std::move(Err);
 
   return CBA.tell() - BeginOffset;
 }
 
 template <class ELFT>
 void ELFState<ELFT>::initDWARFSectionHeader(Elf_Shdr &SHeader, StringRef Name,
                                             ContiguousBlobAccumulator &CBA,
                                             ELFYAML::Section *YAMLSec) {
   zero(SHeader);
   SHeader.sh_name = getSectionNameOffset(ELFYAML::dropUniqueSuffix(Name));
   SHeader.sh_type = YAMLSec ? YAMLSec->Type : ELF::SHT_PROGBITS;
   SHeader.sh_addralign = YAMLSec ? (uint64_t)YAMLSec->AddressAlign : 1;
   SHeader.sh_offset = alignToOffset(CBA, SHeader.sh_addralign,
                                     YAMLSec ? YAMLSec->Offset : None);
 
   ELFYAML::RawContentSection *RawSec =
       dyn_cast_or_null<ELFYAML::RawContentSection>(YAMLSec);
-  if (Doc.DWARF && shouldEmitDWARF(*Doc.DWARF, Name)) {
+  if (DWARFState && shouldEmitDWARF(DWARFState->getDWARFData(), Name)) {
     if (RawSec && (RawSec->Content || RawSec->Size))
       reportError("cannot specify section '" + Name +
                   "' contents in the 'DWARF' entry and the 'Content' "
                   "or 'Size' in the 'Sections' entry at the same time");
     else {
       if (Expected<uint64_t> ShSizeOrErr =
-              emitDWARF<ELFT>(SHeader, Name, *Doc.DWARF, CBA))
+              emitDWARF<ELFT>(SHeader, Name, *DWARFState, CBA))
         SHeader.sh_size = *ShSizeOrErr;
       else
         reportError(ShSizeOrErr.takeError());
     }
   } else if (RawSec)
     SHeader.sh_size = writeContent(CBA, RawSec->Content, RawSec->Size);
   else
     llvm_unreachable("debug sections can only be initialized via the 'DWARF' "

llvm/lib/ObjectYAML/MachOEmitter.cpp

 //===- yaml2macho - Convert YAML to a Mach object file --------------------===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
 ///
 /// \file
 /// The Mach component of yaml2obj.
 ///
 //===----------------------------------------------------------------------===//
 
 #include "llvm/BinaryFormat/MachO.h"
 #include "llvm/ObjectYAML/DWARFEmitter.h"
+#include "llvm/ObjectYAML/DWARFYAML.h"
 #include "llvm/ObjectYAML/ObjectYAML.h"
 #include "llvm/ObjectYAML/yaml2obj.h"
 #include "llvm/Support/Errc.h"
 #include "llvm/Support/Error.h"
 #include "llvm/Support/LEB128.h"
 #include "llvm/Support/YAMLTraits.h"
 #include "llvm/Support/raw_ostream.h"
 
#include "llvm/BinaryFormat/MachO.def"
     auto BytesRemaining = LC.Data.load_command_data.cmdsize - BytesWritten;
     if (BytesRemaining > 0) {
       ZeroFillBytes(OS, BytesRemaining);
     }
   }
 }
 
 Error MachOWriter::writeSectionData(raw_ostream &OS) {
+  // There might be DWARF sections and they might be interlinked. We use
+  // DWARFState to get them interlinked.
+  Optional<DWARFYAML::DWARFState> DWARFState;
+  if (!Obj.DWARF.isEmpty()) {
+    Expected<DWARFYAML::DWARFState> DSOrErr =
+        DWARFYAML::DWARFState::create(Obj.DWARF);
+    if (DSOrErr)
+      DWARFState.emplace(*DSOrErr);
+    else
+      return DSOrErr.takeError();
+  }
+
   for (auto &LC : Obj.LoadCommands) {
     switch (LC.Data.load_command_data.cmd) {
     case MachO::LC_SEGMENT:
     case MachO::LC_SEGMENT_64:
       uint64_t segOff = is64Bit ? LC.Data.segment_command_64_data.fileoff
                                 : LC.Data.segment_command_data.fileoff;
       if (0 ==
           strncmp(&LC.Data.segment_command_data.segname[0], "__LINKEDIT", 16)) {
         FoundLinkEditSeg = true;
         writeLinkEditData(OS);
       }
       for (auto &Sec : LC.Sections) {
         ZeroToOffset(OS, Sec.offset);
         // Zero Fill any data between the end of the last thing we wrote and the
         // start of this section.
         if (OS.tell() - fileStart > Sec.offset && Sec.offset != (uint32_t)0)
           return createStringError(
               errc::invalid_argument,
               "wrote too much data somewhere, section offsets don't line up");
-        if (0 == strncmp(&Sec.segname[0], "__DWARF", sizeof(Sec.segname))) {
+        if (0 == strncmp(&Sec.segname[0], "__DWARF", sizeof(Sec.segname)) &&
+            DWARFState) {
           StringRef SectName(Sec.sectname,
                              strnlen(Sec.sectname, sizeof(Sec.sectname)));
-          if (Obj.DWARF.getNonEmptySectionNames().count(SectName.substr(2))) {
+          const DWARFYAML::Data &DWARF = DWARFState->getDWARFData();
+          if (DWARF.getNonEmptySectionNames().count(SectName.substr(2))) {
             auto EmitFunc =
                 DWARFYAML::getDWARFEmitterByName(SectName.substr(2));
-            if (Error Err = EmitFunc(OS, Obj.DWARF))
+            if (Error Err = EmitFunc(OS, *DWARFState))
               return Err;
           }
 
           continue;
         }
 
         // Skip if it's a virtual section.
         if (MachO::isVirtualSection(Sec.flags & MachO::SECTION_TYPE))

llvm/test/ObjectYAML/MachO/DWARF-BigEndian.yaml

debug_str:
     - /Users/cbieneman/dev/open-source/llvm-build-rel
     - int
     - di_int
     - long long int
     - __absvdi2
     - a
     - N
     - t
-  debug_abbrev:    
+  debug_abbrev:
+    - Table:
         - Code:            0x00000001
           Tag:             DW_TAG_compile_unit
           Children:        DW_CHILDREN_yes
-      Attributes:      
+          Attributes:
             - Attribute:       DW_AT_producer
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_language
               Form:            DW_FORM_data2
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_stmt_list
               Form:            DW_FORM_sec_offset
             - Attribute:       DW_AT_comp_dir
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_low_pc
               Form:            DW_FORM_addr
             - Attribute:       DW_AT_high_pc
               Form:            DW_FORM_data4
         - Code:            0x00000002
           Tag:             DW_TAG_base_type
           Children:        DW_CHILDREN_no
-      Attributes:      
+          Attributes:
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_encoding
               Form:            DW_FORM_data1
             - Attribute:       DW_AT_byte_size
               Form:            DW_FORM_data1
         - Code:            0x00000003
           Tag:             DW_TAG_typedef
           Children:        DW_CHILDREN_no
-      Attributes:      
+          Attributes:
             - Attribute:       DW_AT_type
               Form:            DW_FORM_ref4
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_decl_file
               Form:            DW_FORM_data1
             - Attribute:       DW_AT_decl_line
               Form:            DW_FORM_data1
         - Code:            0x00000004
           Tag:             DW_TAG_subprogram
           Children:        DW_CHILDREN_yes
-      Attributes:      
+          Attributes:
             - Attribute:       DW_AT_low_pc
               Form:            DW_FORM_addr
             - Attribute:       DW_AT_high_pc
               Form:            DW_FORM_data4
             - Attribute:       DW_AT_frame_base
               Form:            DW_FORM_exprloc
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_decl_file
               Form:            DW_FORM_data1
             - Attribute:       DW_AT_decl_line
               Form:            DW_FORM_data1
             - Attribute:       DW_AT_prototyped
               Form:            DW_FORM_flag_present
             - Attribute:       DW_AT_type
               Form:            DW_FORM_ref4
             - Attribute:       DW_AT_external
               Form:            DW_FORM_flag_present
         - Code:            0x00000005
           Tag:             DW_TAG_formal_parameter
           Children:        DW_CHILDREN_no
-      Attributes:      
+          Attributes:
             - Attribute:       DW_AT_location
               Form:            DW_FORM_exprloc
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_decl_file
               Form:            DW_FORM_data1
             - Attribute:       DW_AT_decl_line
               Form:            DW_FORM_data1
             - Attribute:       DW_AT_type
               Form:            DW_FORM_ref4
         - Code:            0x00000006
           Tag:             DW_TAG_variable
           Children:        DW_CHILDREN_no
-      Attributes:      
+          Attributes:
             - Attribute:       DW_AT_location
               Form:            DW_FORM_exprloc
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_decl_file
               Form:            DW_FORM_data1
             - Attribute:       DW_AT_decl_line
               Form:            DW_FORM_data1
             - Attribute:       DW_AT_type
               Form:            DW_FORM_ref4
         - Code:            0x00000007
           Tag:             DW_TAG_const_type
           Children:        DW_CHILDREN_no
-      Attributes:      
+          Attributes:
             - Attribute:       DW_AT_type
-          Form:            DW_FORM_ref4       
+              Form:            DW_FORM_ref4
 ...
 
 #CHECK: DWARF:           
 #CHECK:   debug_str:       
 #CHECK:     - 'clang version 4.0.0 (trunk 290181) (llvm/trunk 290209)'
 #CHECK:     - '../compiler-rt/lib/builtins/absvdi2.c'
 #CHECK:     - '/Users/cbieneman/dev/open-source/llvm-build-rel'
 #CHECK:     - int

llvm/test/ObjectYAML/MachO/DWARF-LittleEndian.yaml

debug_str:
     - /Users/cbieneman/dev/open-source/llvm-build-rel
     - int
     - di_int
     - long long int
     - __absvdi2
     - a
     - N
     - t
-  debug_abbrev:    
+  debug_abbrev:
+    - Table:
         - Code:            0x00000001
           Tag:             DW_TAG_compile_unit
           Children:        DW_CHILDREN_yes
-      Attributes:      
+          Attributes:
             - Attribute:       DW_AT_producer
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_language
               Form:            DW_FORM_data2
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_stmt_list
               Form:            DW_FORM_sec_offset
             - Attribute:       DW_AT_comp_dir
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_low_pc
               Form:            DW_FORM_addr
             - Attribute:       DW_AT_high_pc
               Form:            DW_FORM_data4
         - Code:            0x00000002
           Tag:             DW_TAG_base_type
           Children:        DW_CHILDREN_no
-      Attributes:      
+          Attributes:
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_encoding
               Form:            DW_FORM_data1
             - Attribute:       DW_AT_byte_size
               Form:            DW_FORM_data1
         - Code:            0x00000003
           Tag:             DW_TAG_typedef
           Children:        DW_CHILDREN_no
-      Attributes:      
+          Attributes:
             - Attribute:       DW_AT_type
               Form:            DW_FORM_ref4
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_decl_file
               Form:            DW_FORM_data1
             - Attribute:       DW_AT_decl_line
               Form:            DW_FORM_data1
         - Code:            0x00000004
           Tag:             DW_TAG_subprogram
           Children:        DW_CHILDREN_yes
-      Attributes:      
+          Attributes:
             - Attribute:       DW_AT_low_pc
               Form:            DW_FORM_addr
             - Attribute:       DW_AT_high_pc
               Form:            DW_FORM_data4
             - Attribute:       DW_AT_frame_base
               Form:            DW_FORM_exprloc
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_decl_file
               Form:            DW_FORM_data1
             - Attribute:       DW_AT_decl_line
               Form:            DW_FORM_data1
             - Attribute:       DW_AT_prototyped
               Form:            DW_FORM_flag_present
             - Attribute:       DW_AT_type
               Form:            DW_FORM_ref4
             - Attribute:       DW_AT_external
               Form:            DW_FORM_flag_present
         - Code:            0x00000005
           Tag:             DW_TAG_formal_parameter
           Children:        DW_CHILDREN_no
-      Attributes:      
+          Attributes:
             - Attribute:       DW_AT_location
               Form:            DW_FORM_exprloc
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_decl_file
               Form:            DW_FORM_data1
             - Attribute:       DW_AT_decl_line
               Form:            DW_FORM_data1
             - Attribute:       DW_AT_type
               Form:            DW_FORM_ref4
         - Code:            0x00000006
           Tag:             DW_TAG_variable
           Children:        DW_CHILDREN_no
-      Attributes:      
+          Attributes:
             - Attribute:       DW_AT_location
               Form:            DW_FORM_exprloc
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_decl_file
               Form:            DW_FORM_data1
             - Attribute:       DW_AT_decl_line
               Form:            DW_FORM_data1
             - Attribute:       DW_AT_type
               Form:            DW_FORM_ref4
         - Code:            0x00000007
           Tag:             DW_TAG_const_type
           Children:        DW_CHILDREN_no
-      Attributes:      
+          Attributes:
             - Attribute:       DW_AT_type
               Form:            DW_FORM_ref4
 ...
 
 #CHECK: DWARF:           
 #CHECK:   debug_str:       
 #CHECK:     - 'clang version 4.0.0 (trunk 290181) (llvm/trunk 290209)'
 #CHECK:     - '../compiler-rt/lib/builtins/absvdi2.c'
 #CHECK:     - '/Users/cbieneman/dev/open-source/llvm-build-rel'
 #CHECK:     - int

llvm/test/ObjectYAML/MachO/DWARF-debug_abbrev.yaml

Sections:
         align:           0
         reloff:          0x00000000
         nreloc:          0
         flags:           0x00000000
         reserved1:       0x00000000
         reserved2:       0x00000000
         reserved3:       0x00000000
 DWARF:           
-  debug_abbrev:     
+  debug_abbrev:
+    - Table:
         - Code:            0x00000001
           Tag:             DW_TAG_compile_unit
           Children:        DW_CHILDREN_yes
-      Attributes:      
+          Attributes:
             - Attribute:       DW_AT_producer
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_language
               Form:            DW_FORM_data2
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_stmt_list
               Form:            DW_FORM_sec_offset
             - Attribute:       DW_AT_comp_dir
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_low_pc
               Form:            DW_FORM_addr
             - Attribute:       DW_AT_high_pc
               Form:            DW_FORM_data4
         - Code:            0x00000002
           Tag:             DW_TAG_subprogram
           Children:        DW_CHILDREN_yes
-      Attributes:      
+          Attributes:
             - Attribute:       DW_AT_low_pc
               Form:            DW_FORM_addr
             - Attribute:       DW_AT_high_pc
               Form:            DW_FORM_data4
             - Attribute:       DW_AT_frame_base
               Form:            DW_FORM_exprloc
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_decl_file
               Form:            DW_FORM_data1
             - Attribute:       DW_AT_decl_line
               Form:            DW_FORM_data1
             - Attribute:       DW_AT_prototyped
               Form:            DW_FORM_flag_present
             - Attribute:       DW_AT_type
               Form:            DW_FORM_ref4
             - Attribute:       DW_AT_external
               Form:            DW_FORM_flag_present
         - Code:            0x00000003
           Tag:             DW_TAG_formal_parameter
           Children:        DW_CHILDREN_no
-      Attributes:      
+          Attributes:
             - Attribute:       DW_AT_location
               Form:            DW_FORM_exprloc
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_decl_file
               Form:            DW_FORM_data1
             - Attribute:       DW_AT_decl_line
               Form:            DW_FORM_data1
             - Attribute:       DW_AT_type
               Form:            DW_FORM_ref4
         - Code:            0x00000004
           Tag:             DW_TAG_base_type
           Children:        DW_CHILDREN_no
-      Attributes:      
+          Attributes:
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_encoding
               Form:            DW_FORM_data1
             - Attribute:       DW_AT_byte_size
               Form:            DW_FORM_data1
         - Code:            0x00000005
           Tag:             DW_TAG_pointer_type
           Children:        DW_CHILDREN_no
-      Attributes:      
+          Attributes:
             - Attribute:       DW_AT_type
               Form:            DW_FORM_ref4
 ...
 
 #CHECK: DWARF:           
 #CHECK:   debug_abbrev:     
 #CHECK:     - Code:            0x0000000000000001
 #CHECK:       Tag:             DW_TAG_compile_unit
 #CHECK:       Children:        DW_CHILDREN_yes
 #CHECK:       Attributes:      

 #CHECK:           Form:            DW_FORM_data1
 #CHECK:         - Attribute:       DW_AT_byte_size
 #CHECK:           Form:            DW_FORM_data1
 #CHECK:     - Code:            0x0000000000000005
 #CHECK:       Tag:             DW_TAG_pointer_type
 #CHECK:       Children:        DW_CHILDREN_no
 #CHECK:       Attributes:      
 #CHECK:         - Attribute:       DW_AT_type
 #CHECK:           Form:            DW_FORM_ref4

llvm/test/ObjectYAML/MachO/DWARF-debug_info.yaml

- n_strx:          22
       n_value:         4294971216
   StringTable:     
     - ''
     - ''
     - __mh_execute_header
     - _main
 DWARF:           
   debug_abbrev:    
+    - Table:
         - Code:            0x00000001
           Tag:             DW_TAG_compile_unit
           Children:        DW_CHILDREN_yes
-      Attributes:      
+          Attributes:
             - Attribute:       DW_AT_producer
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_language
               Form:            DW_FORM_data2
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_stmt_list
               Form:            DW_FORM_sec_offset
             - Attribute:       DW_AT_comp_dir
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_low_pc
               Form:            DW_FORM_addr
             - Attribute:       DW_AT_high_pc
               Form:            DW_FORM_data4
         - Code:            0x00000002
           Tag:             DW_TAG_subprogram
           Children:        DW_CHILDREN_yes
-      Attributes:      
+          Attributes:
             - Attribute:       DW_AT_low_pc
               Form:            DW_FORM_addr
             - Attribute:       DW_AT_high_pc
               Form:            DW_FORM_data4
             - Attribute:       DW_AT_frame_base
               Form:            DW_FORM_exprloc
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_decl_file
               Form:            DW_FORM_data1
             - Attribute:       DW_AT_decl_line
               Form:            DW_FORM_data1
             - Attribute:       DW_AT_prototyped
               Form:            DW_FORM_flag_present
             - Attribute:       DW_AT_type
               Form:            DW_FORM_ref4
             - Attribute:       DW_AT_external
               Form:            DW_FORM_flag_present
         - Code:            0x00000003
           Tag:             DW_TAG_formal_parameter
           Children:        DW_CHILDREN_no
-      Attributes:      
+          Attributes:
             - Attribute:       DW_AT_location
               Form:            DW_FORM_exprloc
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_decl_file
               Form:            DW_FORM_data1
             - Attribute:       DW_AT_decl_line
               Form:            DW_FORM_data1
             - Attribute:       DW_AT_type
               Form:            DW_FORM_ref4
         - Code:            0x00000004
           Tag:             DW_TAG_base_type
           Children:        DW_CHILDREN_no
-      Attributes:      
+          Attributes:
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_encoding
               Form:            DW_FORM_data1
             - Attribute:       DW_AT_byte_size
               Form:            DW_FORM_data1
         - Code:            0x00000005
           Tag:             DW_TAG_pointer_type
           Children:        DW_CHILDREN_no
-      Attributes:      
+          Attributes:
             - Attribute:       DW_AT_type
               Form:            DW_FORM_ref4
   debug_aranges:   
     - Length:              44
       Version:             2
       CuOffset:            0
       AddressSize:         8
       SegmentSelectorSize: 0
       Descriptors:     
         - Address:         0x0000000100000F50
- Length:          65
           ExtLen:          1
           SubOpcode:       DW_LNE_end_sequence
           Data:            11
 ...
 ...
 
 #      DWARF32: DWARF:
 #      DWARF32:   debug_info:
-# DWARF32-NEXT:     - Length:     0x0000000000000075
-# DWARF32-NEXT:       Version:    4
-# DWARF32-NEXT:       AbbrOffset: 0
-# DWARF32-NEXT:       AddrSize:   8
+# DWARF32-NEXT:     - Length:        0x0000000000000075
+# DWARF32-NEXT:       Version:       4
+# DWARF32-NEXT:       AbbrevTableID: 0
+# DWARF32-NEXT:       AbbrOffset:    0
+# DWARF32-NEXT:       AddrSize:      8
 # DWARF32-NEXT:       Entries:
 # DWARF32-NEXT:         - AbbrCode: 0x00000001
 # DWARF32-NEXT:           Values:
 # DWARF32-NEXT:             - Value: 0x0000000000000001
 # DWARF32-NEXT:             - Value: 0x000000000000000C
 # DWARF32-NEXT:             - Value: 0x0000000000000038
 # DWARF32-NEXT:             - Value: 0x0000000000000000
 # DWARF32-NEXT:             - Value: 0x0000000000000046

 ## b) Test that yaml2obj emits a correct unit header and obj2yaml is able to convert it back.
 
 ## Test DWARF32 unit header.
 
 # RUN: yaml2obj --docnum=2 -DFORMAT=DWARF32 %s | \
 # RUN:   obj2yaml | FileCheck %s --check-prefix=DWARF32-YAML
 
 #      DWARF32-YAML: debug_info:
-# DWARF32-YAML-NEXT:   - Length:     0x000000000000000C
-# DWARF32-YAML-NEXT:     Version:    4
-# DWARF32-YAML-NEXT:     AbbrOffset: 0
-# DWARF32-YAML-NEXT:     AddrSize:   8
+# DWARF32-YAML-NEXT:   - Length:        0x000000000000000C
+# DWARF32-YAML-NEXT:     Version:       4
+# DWARF32-YAML-NEXT:     AbbrevTableID: 0
+# DWARF32-YAML-NEXT:     AbbrOffset:    0
+# DWARF32-YAML-NEXT:     AddrSize:      8
 # DWARF32-YAML-NEXT:     Entries:
 # DWARF32-YAML-NEXT:       - AbbrCode: 0x00000001
 # DWARF32-YAML-NEXT:         Values:
 # DWARF32-YAML-NEXT:           - Value: 0x0000000000001234
 
 --- !mach-o
 FileHeader:
   magic:      0xFEEDFACF
Sections:
         align:     0
         reloff:    0x00000000
         nreloc:    0
         flags:     0x00000000
         reserved1: 0x00000000
         reserved2: 0x00000000
         reserved3: 0x00000000
 DWARF:
-  debug_abbrev:    
+  debug_abbrev:
+    - Table:
         - Code:     1
           Tag:      DW_TAG_compile_unit
           Children: DW_CHILDREN_no
           Attributes:
             - Attribute: DW_AT_low_pc
               Form:      DW_FORM_addr
   debug_info:
     - Format:     [[FORMAT]]
       Length:     12
       Version:    4
       AbbrOffset: 0
       AddrSize:   8
       Entries:
         - AbbrCode: 1
           Values:
             - Value: 0x1234
 
 ## Test DWARF64 unit header.
 
 # RUN: yaml2obj --docnum=2 -DFORMAT=DWARF64 %s | \
 # RUN:   obj2yaml | FileCheck %s --check-prefix=DWARF64-YAML
 
 #      DWARF64-YAML: debug_info:
-# DWARF64-YAML-NEXT:   - Format:     DWARF64
-# DWARF64-YAML-NEXT:     Length:     0x000000000000000C
-# DWARF64-YAML-NEXT:     Version:    4
-# DWARF64-YAML-NEXT:     AbbrOffset: 0
-# DWARF64-YAML-NEXT:     AddrSize:   8
+# DWARF64-YAML-NEXT:   - Format:        DWARF64
+# DWARF64-YAML-NEXT:     Length:        0x000000000000000C
+# DWARF64-YAML-NEXT:     Version:       4
+# DWARF64-YAML-NEXT:     AbbrevTableID: 0
+# DWARF64-YAML-NEXT:     AbbrOffset:    0
+# DWARF64-YAML-NEXT:     AddrSize:      8
 # DWARF64-YAML-NEXT:     Entries:
 # DWARF64-YAML-NEXT:       - AbbrCode: 0x00000001
 # DWARF64-YAML-NEXT:         Values:
 # DWARF64-YAML-NEXT:           - Value: 0x0000000000001234
+
+## c) Test that yaml2obj is able to generate compilation units according to the
+## associated abbrev table that is referenced by the 'AbbrevTableID' and obj2yaml
+## is able to convert it back.
+
+# RUN: yaml2obj --docnum=3 %s | obj2yaml | FileCheck %s --check-prefix=MULTI-TABLES
+
+#      MULTI-TABLES: DWARF:
+# MULTI-TABLES-NEXT:   debug_abbrev:
+# MULTI-TABLES-NEXT:     - ID: 0
+# MULTI-TABLES-NEXT:       Table:
+# MULTI-TABLES-NEXT:         - Code:     0x0000000000000001
+# MULTI-TABLES-NEXT:           Tag:      DW_TAG_compile_unit
+# MULTI-TABLES-NEXT:           Children: DW_CHILDREN_no
+# MULTI-TABLES-NEXT:           Attributes:
+# MULTI-TABLES-NEXT:             - Attribute: DW_AT_low_pc
+# MULTI-TABLES-NEXT:               Form:      DW_FORM_addr
+# MULTI-TABLES-NEXT:     - ID: 1
+# MULTI-TABLES-NEXT:       Table:
+# MULTI-TABLES-NEXT:         - Code:     0x0000000000000001
+# MULTI-TABLES-NEXT:           Tag:      DW_TAG_compile_unit
+# MULTI-TABLES-NEXT:           Children: DW_CHILDREN_no
+# MULTI-TABLES-NEXT:           Attributes:
+# MULTI-TABLES-NEXT:             - Attribute: DW_AT_low_pc
+# MULTI-TABLES-NEXT:               Form:      DW_FORM_data4
+# MULTI-TABLES-NEXT:     - ID: 2
+# MULTI-TABLES-NEXT:       Table:
+# MULTI-TABLES-NEXT:         - Code:     0x0000000000000001
+# MULTI-TABLES-NEXT:           Tag:      DW_TAG_compile_unit
+# MULTI-TABLES-NEXT:           Children: DW_CHILDREN_no
+# MULTI-TABLES-NEXT:           Attributes:
+# MULTI-TABLES-NEXT:             - Attribute: DW_AT_low_pc
+# MULTI-TABLES-NEXT:               Form:      DW_FORM_udata
+# MULTI-TABLES-NEXT:   debug_info:
+# MULTI-TABLES-NEXT:     - Length:        0x000000000000000C
+# MULTI-TABLES-NEXT:       Version:       4
+# MULTI-TABLES-NEXT:       AbbrevTableID: 1
+# MULTI-TABLES-NEXT:       AbbrOffset:    0x0000000000000008
+# MULTI-TABLES-NEXT:       AddrSize:      8
+# MULTI-TABLES-NEXT:       Entries:
+# MULTI-TABLES-NEXT:         - AbbrCode: 0x00000001
+# MULTI-TABLES-NEXT:           Values:
+# MULTI-TABLES-NEXT:             - Value: 0x0000000000001234
+# MULTI-TABLES-NEXT:     - Length:        0x000000000000000C
+# MULTI-TABLES-NEXT:       Version:       4
+# MULTI-TABLES-NEXT:       AbbrevTableID: 1
+# MULTI-TABLES-NEXT:       AbbrOffset:    0x0000000000000008
+# MULTI-TABLES-NEXT:       AddrSize:      8
+# MULTI-TABLES-NEXT:       Entries:
+# MULTI-TABLES-NEXT:         - AbbrCode: 0x00000001
+# MULTI-TABLES-NEXT:           Values:
+# MULTI-TABLES-NEXT:             - Value: 0x0000000000004321
+# MULTI-TABLES-NEXT:     - Length:        0x0000000000000010
+# MULTI-TABLES-NEXT:       Version:       4
+# MULTI-TABLES-NEXT:       AbbrevTableID: 0
+# MULTI-TABLES-NEXT:       AbbrOffset:    0x0000000000000000
+# MULTI-TABLES-NEXT:       AddrSize:      8
+# MULTI-TABLES-NEXT:       Entries:
+# MULTI-TABLES-NEXT:         - AbbrCode: 0x00000001
+# MULTI-TABLES-NEXT:           Values:
+# MULTI-TABLES-NEXT:             - Value: 0x0000000000005678
+# MULTI-TABLES-NEXT: ...
+
+--- !mach-o
+FileHeader:
+  magic:      0xFEEDFACF
+  cputype:    0x01000007
+  cpusubtype: 0x00000003
+  filetype:   0x0000000A
+  ncmds:      1
+  sizeofcmds: 232
+  flags:      0x00000000
+  reserved:   0x00000000
+LoadCommands:
+  - cmd:      LC_SEGMENT_64
+    cmdsize:  232
+    segname:  __DWARF
+    vmaddr:   0x00
+    vmsize:   0x00
+    fileoff:  0x00
+    filesize: 0x00
+    maxprot:  0
+    initprot: 0
+    nsects:   2
+    flags:    0
+    Sections:
+      - sectname:  __debug_abbrev
+        segname:   __DWARF
+        addr:      0x00
+        size:      24
+        offset:    528
+        align:     0
+        reloff:    0x00000000
+        nreloc:    0
+        flags:     0x00000000
+        reserved1: 0x00000000
+        reserved2: 0x00000000
+        reserved3: 0x00000000
+      - sectname:  __debug_info
+        segname:   __DWARF
+        addr:      0x00
+        size:      64
+        offset:    1070
+        align:     0
+        reloff:    0x00000000
+        nreloc:    0
+        flags:     0x00000000
+        reserved1: 0x00000000
+        reserved2: 0x00000000
+        reserved3: 0x00000000
+DWARF:
+  debug_abbrev:
+    - Table:
+        - Code:     1
+          Tag:      DW_TAG_compile_unit
+          Children: DW_CHILDREN_no
+          Attributes:
+            - Attribute: DW_AT_low_pc
+              Form:      DW_FORM_addr
+    - ID: 2
+      Table:
+        - Code:     1
+          Tag:      DW_TAG_compile_unit
+          Children: DW_CHILDREN_no
+          Attributes:
+            - Attribute: DW_AT_low_pc
+              Form:      DW_FORM_data4
+    - ID: 1
+      Table:
+        - Code:     1
+          Tag:      DW_TAG_compile_unit
+          Children: DW_CHILDREN_no
+          Attributes:
+            - Attribute: DW_AT_low_pc
+              Form:      DW_FORM_udata
+  debug_info:
+    - Version:       4
+      AbbrevTableID: 2
+      AbbrOffset:    8
+      Entries:
+        - AbbrCode: 1
+          Values:
+            - Value: 0x1234
+    - Version:       4
+      AbbrevTableID: 2
+      AbbrOffset:    8
+      Entries:
+        - AbbrCode: 1
+          Values:
+            - Value: 0x4321
+    - Version:       4
+      AbbrevTableID: 0
+      AbbrOffset:    0
+      Entries:
+        - AbbrCode: 1
+          Values:
+            - Value: 0x5678
+    - Version:       4
+      AbbrevTableID: 1
+      AbbrOffset:    16
+      Entries:
+        - AbbrCode: 1
+          Values:
+            - Value: 0x8765
+
+## d) Test that yaml2obj emits an error message when a compilation unit doesn't have
+## an associated abbrev table.
+
+# RUN: not yaml2obj --docnum=4 %s 2>&1 | FileCheck %s --check-prefix=MISSING-ABBREV
+
+# MISSING-ABBREV: yaml2obj: error: cannot find abbrev table whose ID is 0
+
+--- !mach-o
+FileHeader:
+  magic:      0xFEEDFACF
+  cputype:    0x01000007
+  cpusubtype: 0x00000003
+  filetype:   0x0000000A
+  ncmds:      1
+  sizeofcmds: 232
+  flags:      0x00000000
+  reserved:   0x00000000
+LoadCommands:
+  - cmd:      LC_SEGMENT_64
+    cmdsize:  232
+    segname:  __DWARF
+    vmaddr:   0x00
+    vmsize:   0x00
+    fileoff:  0x00
+    filesize: 0x00
+    maxprot:  0
+    initprot: 0
+    nsects:   2
+    flags:    0
+    Sections:
+      - sectname:  __debug_abbrev
+        segname:   __DWARF
+        addr:      0x00
+        size:      24
+        offset:    528
+        align:     0
+        reloff:    0x00000000
+        nreloc:    0
+        flags:     0x00000000
+        reserved1: 0x00000000
+        reserved2: 0x00000000
+        reserved3: 0x00000000
+      - sectname:  __debug_info
+        segname:   __DWARF
+        addr:      0x00
+        size:      64
+        offset:    1070
+        align:     0
+        reloff:    0x00000000
+        nreloc:    0
+        flags:     0x00000000
+        reserved1: 0x00000000
+        reserved2: 0x00000000
+        reserved3: 0x00000000
+DWARF:
+  debug_info:
+    - Version:    4
+      AbbrOffset: 0x00
+      Entries:
+        - AbbrCode: 1
+          Values:
+            - Value: 0x1234
+
+## e) Test that yaml2obj emits an error message when multiple abbrev tables are assigned
+## the same ID.
+
+# RUN: not yaml2obj --docnum=5 %s 2>&1 | FileCheck %s --check-prefix=ID-COLLISION
+
+# ID-COLLISION: yaml2obj: error: the ID (1) of abbrev table with index 1 has been used
+
+--- !mach-o
+FileHeader:
+  magic:      0xFEEDFACF
+  cputype:    0x01000007
+  cpusubtype: 0x00000003
+  filetype:   0x0000000A
+  ncmds:      1
+  sizeofcmds: 232
+  flags:      0x00000000
+  reserved:   0x00000000
+LoadCommands:
+  - cmd:      LC_SEGMENT_64
+    cmdsize:  232
+    segname:  __DWARF
+    vmaddr:   0x00
+    vmsize:   0x00
+    fileoff:  0x00
+    filesize: 0x00
+    maxprot:  0
+    initprot: 0
+    nsects:   2
+    flags:    0
+    Sections:
+      - sectname:  __debug_abbrev
+        segname:   __DWARF
+        addr:      0x00
+        size:      24
+        offset:    528
+        align:     0
+        reloff:    0x00000000
+        nreloc:    0
+        flags:     0x00000000
+        reserved1: 0x00000000
+        reserved2: 0x00000000
+        reserved3: 0x00000000
+      - sectname:  __debug_info
+        segname:   __DWARF
+        addr:      0x00
+        size:      64
+        offset:    1070
+        align:     0
+        reloff:    0x00000000
+        nreloc:    0
+        flags:     0x00000000
+        reserved1: 0x00000000
+        reserved2: 0x00000000
+        reserved3: 0x00000000
+DWARF:
+  debug_abbrev:
+    - ID: 1
+    - ID: 1

llvm/test/ObjectYAML/MachO/DWARF-debug_line.yaml

debug_str:
     - 'clang version 4.0.0 (trunk 288923) (llvm/trunk 288991)'
     - hello_world.c
     - /Users/cbieneman/dev/open-source/llvm-build-rel
     - main
     - argc
     - argv
     - int
     - char
-  debug_abbrev:    
+  debug_abbrev:
+    - Table:
         - Code:            0x00000001
           Tag:             DW_TAG_compile_unit
           Children:        DW_CHILDREN_yes
-      Attributes:      
+          Attributes:
             - Attribute:       DW_AT_producer
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_language
               Form:            DW_FORM_data2
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_stmt_list
               Form:            DW_FORM_sec_offset
             - Attribute:       DW_AT_comp_dir
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_low_pc
               Form:            DW_FORM_addr
             - Attribute:       DW_AT_high_pc
               Form:            DW_FORM_data4
         - Code:            0x00000002
           Tag:             DW_TAG_subprogram
           Children:        DW_CHILDREN_yes
-      Attributes:      
+          Attributes:
             - Attribute:       DW_AT_low_pc
               Form:            DW_FORM_addr
             - Attribute:       DW_AT_high_pc
               Form:            DW_FORM_data4
             - Attribute:       DW_AT_frame_base
               Form:            DW_FORM_exprloc
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_decl_file
               Form:            DW_FORM_data1
             - Attribute:       DW_AT_decl_line
               Form:            DW_FORM_data1
             - Attribute:       DW_AT_prototyped
               Form:            DW_FORM_flag_present
             - Attribute:       DW_AT_type
               Form:            DW_FORM_ref4
             - Attribute:       DW_AT_external
               Form:            DW_FORM_flag_present
         - Code:            0x00000003
           Tag:             DW_TAG_formal_parameter
           Children:        DW_CHILDREN_no
-      Attributes:      
+          Attributes:
             - Attribute:       DW_AT_location
               Form:            DW_FORM_exprloc
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_decl_file
               Form:            DW_FORM_data1
             - Attribute:       DW_AT_decl_line
               Form:            DW_FORM_data1
             - Attribute:       DW_AT_type
               Form:            DW_FORM_ref4
         - Code:            0x00000004
           Tag:             DW_TAG_base_type
           Children:        DW_CHILDREN_no
-      Attributes:      
+          Attributes:
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_encoding
               Form:            DW_FORM_data1
             - Attribute:       DW_AT_byte_size
               Form:            DW_FORM_data1
         - Code:            0x00000005
           Tag:             DW_TAG_pointer_type
           Children:        DW_CHILDREN_no
-      Attributes:      
+          Attributes:
             - Attribute:       DW_AT_type
               Form:            DW_FORM_ref4
   debug_aranges:   
     - Length:              44
       Version:             2
       CuOffset:            0
       AddressSize:         8
       SegmentSelectorSize: 0
       Descriptors:     
         - Address:         0x0000000100000F50

llvm/test/ObjectYAML/MachO/DWARF-debug_ranges.yaml

 DWARF:
   debug_str:
     - ''
     - '/tmp/main.c'
     - stripped1
     - stripped2
     - main
   debug_abbrev:
+    - Table:
         - Code:            0x00000001
           Tag:             DW_TAG_compile_unit
           Children:        DW_CHILDREN_yes
           Attributes:
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_language
               Form:            DW_FORM_data2
             - Attribute:       DW_AT_low_pc
               Form:            DW_FORM_addr
             - Attribute:       DW_AT_ranges
               Form:            DW_FORM_sec_offset
         - Code:            0x00000002
           Tag:             DW_TAG_subprogram
           Children:        DW_CHILDREN_no
           Attributes:
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_low_pc
               Form:            DW_FORM_addr
             - Attribute:       DW_AT_high_pc
               Form:            DW_FORM_data4
         - Code:            0x00000003
           Tag:             DW_TAG_subprogram
           Children:        DW_CHILDREN_no
           Attributes:
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_low_pc
               Form:            DW_FORM_addr
             - Attribute:       DW_AT_high_pc
               Form:            DW_FORM_addr
   debug_ranges:
     - Offset:          0x00000000
       Entries:
         - LowOffset:       0x0000000000000000
           HighOffset:      0x0000000000000020
         - LowOffset:       0x0000000000000000
           HighOffset:      0x0000000000000030
         - LowOffset:       0xFFFFFFFFFFFFFFFF

llvm/test/ObjectYAML/MachO/DWARF2-AddrSize8-FormValues.yaml

Sections:
         nreloc:          0
         flags:           0x00000000
         reserved1:       0x00000000
         reserved2:       0x00000000
         reserved3:       0x00000000
 DWARF:
   debug_str:       
     - World
-  debug_abbrev:    
+  debug_abbrev:
+    - Table:
         - Code:            0x00000001
           Tag:             DW_TAG_compile_unit
           Children:        DW_CHILDREN_no
-      Attributes:      
+          Attributes:
             - Attribute:       0x2000
               Form:            DW_FORM_addr
             - Attribute:       0x2001
               Form:            DW_FORM_block
             - Attribute:       DW_AT_MIPS_loop_begin
               Form:            DW_FORM_block1
             - Attribute:       DW_AT_MIPS_tail_loop_begin
               Form:            DW_FORM_block2
             - Attribute:       DW_AT_MIPS_epilog_begin
               Form:            DW_FORM_block4
             - Attribute:       DW_AT_MIPS_loop_unroll_factor
               Form:            DW_FORM_data1
             - Attribute:       DW_AT_MIPS_software_pipeline_depth
               Form:            DW_FORM_data2
             - Attribute:       DW_AT_MIPS_linkage_name
               Form:            DW_FORM_data4
             - Attribute:       DW_AT_MIPS_stride
               Form:            DW_FORM_data8
             - Attribute:       DW_AT_MIPS_abstract_name
               Form:            DW_FORM_string
             - Attribute:       DW_AT_MIPS_clone_origin
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_MIPS_has_inlines
               Form:            DW_FORM_ref_addr
             - Attribute:       DW_AT_MIPS_stride_byte
               Form:            DW_FORM_ref1
             - Attribute:       DW_AT_MIPS_stride_elem
               Form:            DW_FORM_ref2
             - Attribute:       DW_AT_MIPS_ptr_dopetype
               Form:            DW_FORM_ref4
             - Attribute:       DW_AT_MIPS_allocatable_dopetype
               Form:            DW_FORM_ref8
             - Attribute:       DW_AT_MIPS_assumed_shape_dopetype
               Form:            DW_FORM_ref_sig8
             - Attribute:       DW_AT_MIPS_assumed_size
               Form:            DW_FORM_ref_udata
             - Attribute:       0x2012
               Form:            DW_FORM_flag
             - Attribute:       0x2013
               Form:            DW_FORM_flag
             - Attribute:       0x2014
               Form:            DW_FORM_flag_present
             - Attribute:       0x2015
               Form:            DW_FORM_sdata
             - Attribute:       0x2017
               Form:            DW_FORM_udata
             - Attribute:       0x2018
               Form:            DW_FORM_GNU_ref_alt
             - Attribute:       0x2019
               Form:            DW_FORM_sec_offset
             - Attribute:       0x201A
               Form:            DW_FORM_addr
   debug_info:      
     - Length:          168
       Version:         2
       AbbrOffset:      0
       AddrSize:        8
       Entries:         
         - AbbrCode:        0x00000001
           Values:          

llvm/test/ObjectYAML/MachO/DWARF5-abbrevValues.yaml

Sections:
         align:           0
         reloff:          0x00000000
         nreloc:          0
         flags:           0x00000000
         reserved1:       0x00000000
         reserved2:       0x00000000
         reserved3:       0x00000000
 DWARF:           
-  debug_abbrev:     
+  debug_abbrev:
+    - Table:
         - Code:            0x00000001
           Tag:             DW_TAG_compile_unit
           Children:        DW_CHILDREN_yes
-      Attributes:      
+          Attributes:
             - Attribute:       0x2001
               Form:            DW_FORM_implicit_const
               Value:           0x12345678
 ...
 
 #CHECK: DWARF:           
 #CHECK:   debug_abbrev:
 #CHECK:     - Code:            0x0000000000000001
 #CHECK:       Tag:             DW_TAG_compile_unit
 #CHECK:       Children:        DW_CHILDREN_yes
 #CHECK:       Attributes:
 #CHECK:         - Attribute:       0x2001
 #CHECK:           Form:            DW_FORM_implicit_const
 #CHECK:           Value:           0x0000000012345678

llvm/test/ObjectYAML/MachO/DWARF5-debug_info.yaml

- n_strx:          22
       n_value:         4294971216
   StringTable:     
     - ''
     - ''
     - __mh_execute_header
     - _main
 DWARF:           
   debug_abbrev:    
+    - Table:
         - Code:            0x00000001
           Tag:             DW_TAG_compile_unit
           Children:        DW_CHILDREN_yes
-      Attributes:      
+          Attributes:
             - Attribute:       DW_AT_producer
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_language
               Form:            DW_FORM_data2
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_stmt_list
               Form:            DW_FORM_sec_offset
             - Attribute:       DW_AT_comp_dir
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_low_pc
               Form:            DW_FORM_addr
             - Attribute:       DW_AT_high_pc
               Form:            DW_FORM_data4
         - Code:            0x00000002
           Tag:             DW_TAG_subprogram
           Children:        DW_CHILDREN_yes
-      Attributes:      
+          Attributes:
             - Attribute:       DW_AT_low_pc
               Form:            DW_FORM_addr
             - Attribute:       DW_AT_high_pc
               Form:            DW_FORM_data4
             - Attribute:       DW_AT_frame_base
               Form:            DW_FORM_exprloc
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_decl_file
               Form:            DW_FORM_data1
             - Attribute:       DW_AT_decl_line
               Form:            DW_FORM_data1
             - Attribute:       DW_AT_prototyped
               Form:            DW_FORM_flag_present
             - Attribute:       DW_AT_type
               Form:            DW_FORM_ref4
             - Attribute:       DW_AT_external
               Form:            DW_FORM_flag_present
         - Code:            0x00000003
           Tag:             DW_TAG_formal_parameter
           Children:        DW_CHILDREN_no
-      Attributes:      
+          Attributes:
             - Attribute:       DW_AT_location
               Form:            DW_FORM_exprloc
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_decl_file
               Form:            DW_FORM_data1
             - Attribute:       DW_AT_decl_line
               Form:            DW_FORM_data1
             - Attribute:       DW_AT_type
               Form:            DW_FORM_ref4
         - Code:            0x00000004
           Tag:             DW_TAG_base_type
           Children:        DW_CHILDREN_no
-      Attributes:      
+          Attributes:
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_encoding
               Form:            DW_FORM_data1
             - Attribute:       DW_AT_byte_size
               Form:            DW_FORM_data1
         - Code:            0x00000005
           Tag:             DW_TAG_pointer_type
           Children:        DW_CHILDREN_no
-      Attributes:      
+          Attributes:
             - Attribute:       DW_AT_type
               Form:            DW_FORM_ref4
   debug_aranges:   
     - Length:              44
       Version:             2
       CuOffset:            0
       AddressSize:         8
       SegmentSelectorSize: 0
       Descriptors:     
         - Address:         0x0000000100000F50
- Length:          65
         - Opcode:          DW_LNS_extended_op
           ExtLen:          1
           SubOpcode:       DW_LNE_end_sequence
           Data:            11
 ...
 
 #      DWARF32: DWARF:
 #      DWARF32:   debug_info:
-# DWARF32-NEXT:     - Length:     0x0000000000000076
-# DWARF32-NEXT:       Version:    5
-# DWARF32-NEXT:       UnitType:   DW_UT_compile
-# DWARF32-NEXT:       AbbrOffset: 0
-# DWARF32-NEXT:       AddrSize:   8
+# DWARF32-NEXT:     - Length:        0x0000000000000076
+# DWARF32-NEXT:       Version:       5
+# DWARF32-NEXT:       UnitType:      DW_UT_compile
+# DWARF32-NEXT:       AbbrevTableID: 0
+# DWARF32-NEXT:       AbbrOffset:    0
+# DWARF32-NEXT:       AddrSize:      8
 # DWARF32-NEXT:       Entries:
 # DWARF32-NEXT:         - AbbrCode: 0x00000001
 # DWARF32-NEXT:           Values:
 # DWARF32-NEXT:             - Value: 0x0000000000000001
 # DWARF32-NEXT:             - Value: 0x000000000000000C
 # DWARF32-NEXT:             - Value: 0x0000000000000038
 # DWARF32-NEXT:             - Value: 0x0000000000000000
 # DWARF32-NEXT:             - Value: 0x0000000000000046

 ## b) Test that yaml2obj emits a correct unit header and obj2yaml is able to convert it back.
 
 ## Test DWARF32 unit header.
 
 # RUN: yaml2obj --docnum=2 -DFORMAT=DWARF32 -DLENGTH=12 %s | \
 # RUN:   obj2yaml | FileCheck %s --check-prefix=DWARF32-YAML
 
 #      DWARF32-YAML: debug_info:
-# DWARF32-YAML-NEXT:   - Length:     0x000000000000000C
-# DWARF32-YAML-NEXT:     Version:    5
-# DWARF32-YAML-NEXT:     UnitType:   DW_UT_compile
-# DWARF32-YAML-NEXT:     AbbrOffset: 0x0000000000000000
-# DWARF32-YAML-NEXT:     AddrSize:   8
+# DWARF32-YAML-NEXT:   - Length:        0x000000000000000C
+# DWARF32-YAML-NEXT:     Version:       5
+# DWARF32-YAML-NEXT:     UnitType:      DW_UT_compile
+# DWARF32-YAML-NEXT:     AbbrevTableID: 0
+# DWARF32-YAML-NEXT:     AbbrOffset:    0x0000000000000000
+# DWARF32-YAML-NEXT:     AddrSize:      8
 # DWARF32-YAML-NEXT:     Entries:
 # DWARF32-YAML-NEXT:       - AbbrCode: 0x00000001
 # DWARF32-YAML-NEXT:         Values:
 # DWARF32-YAML-NEXT:           - Value: 0x0000000000001234
 
 --- !mach-o
 FileHeader:
   magic:      0xFEEDFACF
Sections:
         reloff:    0x00000000
         nreloc:    0
         flags:     0x00000000
         reserved1: 0x00000000
         reserved2: 0x00000000
         reserved3: 0x00000000
 DWARF:
   debug_abbrev:    
+    - Table:
         - Code:     1
           Tag:      DW_TAG_compile_unit
           Children: DW_CHILDREN_no
           Attributes:
             - Attribute: DW_AT_low_pc
               Form:      DW_FORM_addr
   debug_info:
     - Format:     [[FORMAT]]
       Length:     [[LENGTH]]
       Version:    5
       UnitType:   DW_UT_compile
       AbbrOffset: 0
       AddrSize:   8
       Entries:
         - AbbrCode: 1
           Values:
             - Value: 0x1234
 
 ## Test DWARF64 unit header.
 
 # RUN: yaml2obj --docnum=2 -DFORMAT=DWARF64 -DLENGTH=20 %s | \
 # RUN:   obj2yaml | FileCheck %s --check-prefix=DWARF64-YAML
 
 #      DWARF64-YAML: debug_info:
-# DWARF64-YAML-NEXT:   - Format:     DWARF64
-# DWARF64-YAML-NEXT:     Length:     0x0000000000000014
-# DWARF64-YAML-NEXT:     Version:    5
-# DWARF64-YAML-NEXT:     UnitType:   DW_UT_compile
-# DWARF64-YAML-NEXT:     AbbrOffset: 0x0000000000000000
-# DWARF64-YAML-NEXT:     AddrSize:   8
+# DWARF64-YAML-NEXT:   - Format:        DWARF64
+# DWARF64-YAML-NEXT:     Length:        0x0000000000000014
+# DWARF64-YAML-NEXT:     Version:       5
+# DWARF64-YAML-NEXT:     UnitType:      DW_UT_compile
+# DWARF64-YAML-NEXT:     AbbrevTableID: 0
+# DWARF64-YAML-NEXT:     AbbrOffset:    0x0000000000000000
+# DWARF64-YAML-NEXT:     AddrSize:      8
 # DWARF64-YAML-NEXT:     Entries:
 # DWARF64-YAML-NEXT:       - AbbrCode: 0x00000001
 # DWARF64-YAML-NEXT:         Values:
 # DWARF64-YAML-NEXT:           - Value: 0x0000000000001234

llvm/test/tools/llvm-dwarfdump/X86/verify_attr_file_indexes.yaml

FileHeader:
   Machine: EM_X86_64
 DWARF:
   debug_str:
     - ''
     - '/tmp/main.c'
     - main
     - inline1
   debug_abbrev:
+    - Table:
         - Code:            0x0000000000000001
           Tag:             DW_TAG_compile_unit
           Children:        DW_CHILDREN_yes
           Attributes:
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_language
               Form:            DW_FORM_data2
             - Attribute:       DW_AT_low_pc
               Form:            DW_FORM_addr
             - Attribute:       DW_AT_stmt_list
               Form:            DW_FORM_sec_offset
         - Code:            0x0000000000000002
           Tag:             DW_TAG_subprogram
           Children:        DW_CHILDREN_yes
           Attributes:
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_low_pc
               Form:            DW_FORM_addr
             - Attribute:       DW_AT_high_pc
               Form:            DW_FORM_addr
             - Attribute:       DW_AT_decl_file
               Form:            DW_FORM_data1
             - Attribute:       DW_AT_call_line
               Form:            DW_FORM_data1
         - Code:            0x0000000000000003
           Tag:             DW_TAG_inlined_subroutine
           Children:        DW_CHILDREN_no
           Attributes:
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_low_pc
               Form:            DW_FORM_addr
             - Attribute:       DW_AT_high_pc
               Form:            DW_FORM_data4
             - Attribute:       DW_AT_call_file
               Form:            DW_FORM_data1
             - Attribute:       DW_AT_call_line
               Form:            DW_FORM_data1
   debug_info:
     - Length:          0x0000000000000046
       Version:         4
       AbbrOffset:      0x0000000000000000
       AddrSize:        8
       Entries:
         - AbbrCode:        0x00000001
           Values:

llvm/test/tools/llvm-dwarfdump/X86/verify_attr_file_indexes_no_files.yaml

FileHeader:
   Machine: EM_X86_64
 DWARF:
   debug_str:
     - ''
     - '/tmp/main.c'
     - main
     - inline1
   debug_abbrev:
+    - Table:
         - Code:            0x0000000000000001
           Tag:             DW_TAG_compile_unit
           Children:        DW_CHILDREN_yes
           Attributes:
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_language
               Form:            DW_FORM_data2
             - Attribute:       DW_AT_low_pc
               Form:            DW_FORM_addr
             - Attribute:       DW_AT_stmt_list
               Form:            DW_FORM_sec_offset
         - Code:            0x0000000000000002
           Tag:             DW_TAG_subprogram
           Children:        DW_CHILDREN_yes
           Attributes:
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_low_pc
               Form:            DW_FORM_addr
             - Attribute:       DW_AT_high_pc
               Form:            DW_FORM_addr
             - Attribute:       DW_AT_decl_file
               Form:            DW_FORM_data1
             - Attribute:       DW_AT_call_line
               Form:            DW_FORM_data1
         - Code:            0x0000000000000003
           Tag:             DW_TAG_inlined_subroutine
           Children:        DW_CHILDREN_no
           Attributes:
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_low_pc
               Form:            DW_FORM_addr
             - Attribute:       DW_AT_high_pc
               Form:            DW_FORM_data4
             - Attribute:       DW_AT_call_file
               Form:            DW_FORM_data1
             - Attribute:       DW_AT_call_line
               Form:            DW_FORM_data1
   debug_info:
     - Length:          0x0000000000000046
       Version:         4
       AbbrOffset:      0x0000000000000000
       AddrSize:        8
       Entries:
         - AbbrCode:        0x00000001
           Values:

llvm/test/tools/llvm-dwarfdump/X86/verify_file_encoding.yaml

 DWARF:
   debug_str:
     - ''
     - '/tmp/main.c'
     - main
     - ''
     - inline1
   debug_abbrev:
+    - Table:
         - Code:            0x0000000000000001
           Tag:             DW_TAG_compile_unit
           Children:        DW_CHILDREN_yes
           Attributes:
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_language
               Form:            DW_FORM_data2
             - Attribute:       DW_AT_low_pc
               Form:            DW_FORM_addr
         - Code:            0x0000000000000002
           Tag:             DW_TAG_subprogram
           Children:        DW_CHILDREN_yes
           Attributes:
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_low_pc
               Form:            DW_FORM_addr
             - Attribute:       DW_AT_high_pc
               Form:            DW_FORM_addr
             - Attribute:       DW_AT_decl_file
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_call_line
               Form:            DW_FORM_data1
         - Code:            0x0000000000000003
           Tag:             DW_TAG_inlined_subroutine
           Children:        DW_CHILDREN_no
           Attributes:
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_low_pc
               Form:            DW_FORM_addr
             - Attribute:       DW_AT_high_pc
               Form:            DW_FORM_data4
             - Attribute:       DW_AT_call_file
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_call_line
               Form:            DW_FORM_data1
   debug_info:
     - Length:          0x0000000000000048
       Version:         4
       AbbrOffset:      0x0000000000000000
       AddrSize:        8
       Entries:
         - AbbrCode:        0x00000001
           Values:

llvm/test/tools/llvm-dwarfdump/X86/verify_overlapping_cu_ranges.yaml

DWARF:
   debug_str:
     - ''
     - '/tmp/main.c'
     - stripped1
     - stripped2
     - main
     - foo
   debug_abbrev:
+    - Table:
         - Code:            0x00000001
           Tag:             DW_TAG_compile_unit
           Children:        DW_CHILDREN_yes
           Attributes:
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_language
               Form:            DW_FORM_data2
             - Attribute:       DW_AT_low_pc
               Form:            DW_FORM_addr
             - Attribute:       DW_AT_ranges
               Form:            DW_FORM_sec_offset
         - Code:            0x00000002
           Tag:             DW_TAG_subprogram
           Children:        DW_CHILDREN_no
           Attributes:
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_low_pc
               Form:            DW_FORM_addr
             - Attribute:       DW_AT_high_pc
               Form:            DW_FORM_data4
         - Code:            0x00000003
           Tag:             DW_TAG_subprogram
           Children:        DW_CHILDREN_no
           Attributes:
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_low_pc
               Form:            DW_FORM_addr
             - Attribute:       DW_AT_high_pc
               Form:            DW_FORM_addr
   debug_ranges:
     - Offset:          0x00000000
       AddrSize:        0x08
       Entries:
         - LowOffset:       0x0000000000002000
           HighOffset:      0x0000000000003000
         - LowOffset:       0x0000000000000000
           HighOffset:      0x0000000000000020

llvm/test/tools/llvm-gsymutil/ARM_AArch64/fat-macho-dwarf.yaml

DWARF:
         - main.cpp
         - '/tmp'
         - main
         - argc
         - argv
         - int
         - char
       debug_abbrev:
+        - Table:
             - Code:            0x00000001
               Tag:             DW_TAG_compile_unit
               Children:        DW_CHILDREN_yes
               Attributes:
                 - Attribute:       DW_AT_producer
                   Form:            DW_FORM_strp
                 - Attribute:       DW_AT_language
                   Form:            DW_FORM_data2
                 - Attribute:       DW_AT_name
                   Form:            DW_FORM_strp
                 - Attribute:       DW_AT_stmt_list
                   Form:            DW_FORM_sec_offset
                 - Attribute:       DW_AT_comp_dir
                   Form:            DW_FORM_strp
                 - Attribute:       DW_AT_GNU_pubnames
                   Form:            DW_FORM_flag_present
                 - Attribute:       DW_AT_low_pc
                   Form:            DW_FORM_addr
                 - Attribute:       DW_AT_high_pc
                   Form:            DW_FORM_data4
             - Code:            0x00000002
               Tag:             DW_TAG_subprogram
               Children:        DW_CHILDREN_yes
               Attributes:
                 - Attribute:       DW_AT_low_pc
                   Form:            DW_FORM_addr
                 - Attribute:       DW_AT_high_pc
                   Form:            DW_FORM_data4
                 - Attribute:       DW_AT_frame_base
                   Form:            DW_FORM_exprloc
                 - Attribute:       DW_AT_name
                   Form:            DW_FORM_strp
                 - Attribute:       DW_AT_decl_file
                   Form:            DW_FORM_data1
                 - Attribute:       DW_AT_decl_line
                   Form:            DW_FORM_data1
                 - Attribute:       DW_AT_type
                   Form:            DW_FORM_ref_addr
                 - Attribute:       DW_AT_external
                   Form:            DW_FORM_flag_present
                 - Attribute:       DW_AT_APPLE_isa
                   Form:            DW_FORM_flag
             - Code:            0x00000003
               Tag:             DW_TAG_formal_parameter
               Children:        DW_CHILDREN_no
               Attributes:
                 - Attribute:       DW_AT_location
                   Form:            DW_FORM_exprloc
                 - Attribute:       DW_AT_name
                   Form:            DW_FORM_strp
                 - Attribute:       DW_AT_decl_file
                   Form:            DW_FORM_data1
                 - Attribute:       DW_AT_decl_line
                   Form:            DW_FORM_data1
                 - Attribute:       DW_AT_type
                   Form:            DW_FORM_ref_addr
             - Code:            0x00000004
               Tag:             DW_TAG_base_type
               Children:        DW_CHILDREN_no
               Attributes:
                 - Attribute:       DW_AT_name
                   Form:            DW_FORM_strp
                 - Attribute:       DW_AT_encoding
                   Form:            DW_FORM_data1
                 - Attribute:       DW_AT_byte_size
                   Form:            DW_FORM_data1
             - Code:            0x00000005
               Tag:             DW_TAG_pointer_type
               Children:        DW_CHILDREN_no
               Attributes:
                 - Attribute:       DW_AT_type
                   Form:            DW_FORM_ref_addr
             - Code:            0x00000006
               Tag:             DW_TAG_const_type
               Children:        DW_CHILDREN_no
               Attributes:
                 - Attribute:       DW_AT_type
                   Form:            DW_FORM_ref_addr
       debug_aranges:
         - Length:              28
           Version:             2
           CuOffset:            0
           AddressSize:         4
           SegmentSelectorSize: 0
           Descriptors:
             - Address:         0x000000000000BFF0
DWARF:
         - main.cpp
         - '/tmp'
         - main
         - argc
         - argv
         - int
         - char
       debug_abbrev:
+        - Table:
             - Code:            0x00000001
               Tag:             DW_TAG_compile_unit
               Children:        DW_CHILDREN_yes
               Attributes:
                 - Attribute:       DW_AT_producer
                   Form:            DW_FORM_strp
                 - Attribute:       DW_AT_language
                   Form:            DW_FORM_data2
                 - Attribute:       DW_AT_name
                   Form:            DW_FORM_strp
                 - Attribute:       DW_AT_stmt_list
                   Form:            DW_FORM_sec_offset
                 - Attribute:       DW_AT_comp_dir
                   Form:            DW_FORM_strp
                 - Attribute:       DW_AT_GNU_pubnames
                   Form:            DW_FORM_flag_present
                 - Attribute:       DW_AT_low_pc
                   Form:            DW_FORM_addr
                 - Attribute:       DW_AT_high_pc
                   Form:            DW_FORM_data4
             - Code:            0x00000002
               Tag:             DW_TAG_subprogram
               Children:        DW_CHILDREN_yes
               Attributes:
                 - Attribute:       DW_AT_low_pc
                   Form:            DW_FORM_addr
                 - Attribute:       DW_AT_high_pc
                   Form:            DW_FORM_data4
                 - Attribute:       DW_AT_frame_base
                   Form:            DW_FORM_exprloc
                 - Attribute:       DW_AT_name
                   Form:            DW_FORM_strp
                 - Attribute:       DW_AT_decl_file
                   Form:            DW_FORM_data1
                 - Attribute:       DW_AT_decl_line
                   Form:            DW_FORM_data1
                 - Attribute:       DW_AT_type
                   Form:            DW_FORM_ref_addr
                 - Attribute:       DW_AT_external
                   Form:            DW_FORM_flag_present
             - Code:            0x00000003
               Tag:             DW_TAG_formal_parameter
               Children:        DW_CHILDREN_no
               Attributes:
                 - Attribute:       DW_AT_location
                   Form:            DW_FORM_exprloc
                 - Attribute:       DW_AT_name
                   Form:            DW_FORM_strp
                 - Attribute:       DW_AT_decl_file
                   Form:            DW_FORM_data1
                 - Attribute:       DW_AT_decl_line
                   Form:            DW_FORM_data1
                 - Attribute:       DW_AT_type
                   Form:            DW_FORM_ref_addr
             - Code:            0x00000004
               Tag:             DW_TAG_base_type
               Children:        DW_CHILDREN_no
               Attributes:
                 - Attribute:       DW_AT_name
                   Form:            DW_FORM_strp
                 - Attribute:       DW_AT_encoding
                   Form:            DW_FORM_data1
                 - Attribute:       DW_AT_byte_size
                   Form:            DW_FORM_data1
             - Code:            0x00000005
               Tag:             DW_TAG_pointer_type
               Children:        DW_CHILDREN_no
               Attributes:
                 - Attribute:       DW_AT_type
                   Form:            DW_FORM_ref_addr
             - Code:            0x00000006
               Tag:             DW_TAG_const_type
               Children:        DW_CHILDREN_no
               Attributes:
                 - Attribute:       DW_AT_type
                   Form:            DW_FORM_ref_addr
       debug_aranges:
         - Length:              44
           Version:             2
           CuOffset:            0
           AddressSize:         8
           SegmentSelectorSize: 0
           Descriptors:
             - Address:         0x0000000100007F9C

llvm/test/tools/llvm-gsymutil/X86/mach-dwarf.yaml

debug_str:
     - foo
     - i
     - int
     - main
     - argc
     - argv
     - char
   debug_abbrev:
+    - Table:
         - Code:            0x00000001
           Tag:             DW_TAG_compile_unit
           Children:        DW_CHILDREN_yes
           Attributes:
             - Attribute:       DW_AT_producer
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_language
               Form:            DW_FORM_data2
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_stmt_list
               Form:            DW_FORM_sec_offset
             - Attribute:       DW_AT_comp_dir
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_GNU_pubnames
               Form:            DW_FORM_flag_present
             - Attribute:       DW_AT_low_pc
               Form:            DW_FORM_addr
             - Attribute:       DW_AT_high_pc
               Form:            DW_FORM_data4
         - Code:            0x00000002
           Tag:             DW_TAG_subprogram
           Children:        DW_CHILDREN_yes
           Attributes:
             - Attribute:       DW_AT_low_pc
               Form:            DW_FORM_addr
             - Attribute:       DW_AT_high_pc
               Form:            DW_FORM_data4
             - Attribute:       DW_AT_frame_base
               Form:            DW_FORM_exprloc
             - Attribute:       DW_AT_abstract_origin
               Form:            DW_FORM_ref_addr
         - Code:            0x00000003
           Tag:             DW_TAG_formal_parameter
           Children:        DW_CHILDREN_no
           Attributes:
             - Attribute:       DW_AT_location
               Form:            DW_FORM_exprloc
             - Attribute:       DW_AT_abstract_origin
               Form:            DW_FORM_ref_addr
         - Code:            0x00000004
           Tag:             DW_TAG_subprogram
           Children:        DW_CHILDREN_yes
           Attributes:
             - Attribute:       DW_AT_linkage_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_decl_file
               Form:            DW_FORM_data1
             - Attribute:       DW_AT_decl_line
               Form:            DW_FORM_data1
             - Attribute:       DW_AT_type
               Form:            DW_FORM_ref_addr
             - Attribute:       DW_AT_external
               Form:            DW_FORM_flag_present
             - Attribute:       DW_AT_inline
               Form:            DW_FORM_data1
         - Code:            0x00000005
           Tag:             DW_TAG_formal_parameter
           Children:        DW_CHILDREN_no
           Attributes:
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_decl_file
               Form:            DW_FORM_data1
             - Attribute:       DW_AT_decl_line
               Form:            DW_FORM_data1
             - Attribute:       DW_AT_type
               Form:            DW_FORM_ref_addr
         - Code:            0x00000006
           Tag:             DW_TAG_base_type
           Children:        DW_CHILDREN_no
           Attributes:
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_encoding
               Form:            DW_FORM_data1
             - Attribute:       DW_AT_byte_size
               Form:            DW_FORM_data1
         - Code:            0x00000007
           Tag:             DW_TAG_subprogram
           Children:        DW_CHILDREN_yes
           Attributes:
             - Attribute:       DW_AT_low_pc
               Form:            DW_FORM_addr
             - Attribute:       DW_AT_high_pc
               Form:            DW_FORM_data4
             - Attribute:       DW_AT_frame_base
               Form:            DW_FORM_exprloc
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_decl_file
               Form:            DW_FORM_data1
             - Attribute:       DW_AT_decl_line
               Form:            DW_FORM_data1
             - Attribute:       DW_AT_type
               Form:            DW_FORM_ref_addr
             - Attribute:       DW_AT_external
               Form:            DW_FORM_flag_present
         - Code:            0x00000008
           Tag:             DW_TAG_formal_parameter
           Children:        DW_CHILDREN_no
           Attributes:
             - Attribute:       DW_AT_location
               Form:            DW_FORM_exprloc
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_decl_file
               Form:            DW_FORM_data1
             - Attribute:       DW_AT_decl_line
               Form:            DW_FORM_data1
             - Attribute:       DW_AT_type
               Form:            DW_FORM_ref_addr
         - Code:            0x00000009
           Tag:             DW_TAG_variable
           Children:        DW_CHILDREN_no
           Attributes:
             - Attribute:       DW_AT_location
               Form:            DW_FORM_exprloc
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_decl_file
               Form:            DW_FORM_data1
             - Attribute:       DW_AT_decl_line
               Form:            DW_FORM_data1
             - Attribute:       DW_AT_type
               Form:            DW_FORM_ref_addr
         - Code:            0x0000000A
           Tag:             DW_TAG_inlined_subroutine
           Children:        DW_CHILDREN_yes
           Attributes:
             - Attribute:       DW_AT_abstract_origin
               Form:            DW_FORM_ref_addr
             - Attribute:       DW_AT_low_pc
               Form:            DW_FORM_addr
             - Attribute:       DW_AT_high_pc
               Form:            DW_FORM_data4
             - Attribute:       DW_AT_call_file
               Form:            DW_FORM_data1
             - Attribute:       DW_AT_call_line
               Form:            DW_FORM_data1
         - Code:            0x0000000B
           Tag:             DW_TAG_pointer_type
           Children:        DW_CHILDREN_no
           Attributes:
             - Attribute:       DW_AT_type
               Form:            DW_FORM_ref_addr
         - Code:            0x0000000C
           Tag:             DW_TAG_const_type
           Children:        DW_CHILDREN_no
           Attributes:
             - Attribute:       DW_AT_type
               Form:            DW_FORM_ref_addr
   debug_aranges:
     - Length:              60
       Version:             2
       CuOffset:            0
       AddressSize:         8
       SegmentSelectorSize: 0
       Descriptors:
         - Address:         0x0000000100000F70

llvm/test/tools/llvm-objcopy/MachO/Inputs/strip-all-with-dwarf.yaml

debug_str:
     - 'Apple LLVM version 10.0.1 (clang-1001.0.46.4)'
     - strip-test.c
     - '/Users/seiya/dev/llvm-project/llvm/build'
     - foo
     - int
     - bar
     - main
   debug_abbrev:
+    - Table:
         - Code:            0x00000001
           Tag:             DW_TAG_compile_unit
           Children:        DW_CHILDREN_yes
           Attributes:
             - Attribute:       DW_AT_producer
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_language
               Form:            DW_FORM_data2
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_stmt_list
               Form:            DW_FORM_sec_offset
             - Attribute:       DW_AT_comp_dir
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_low_pc
               Form:            DW_FORM_addr
             - Attribute:       DW_AT_high_pc
               Form:            DW_FORM_data4
         - Code:            0x00000002
           Tag:             DW_TAG_variable
           Children:        DW_CHILDREN_no
           Attributes:
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_type
               Form:            DW_FORM_ref4
             - Attribute:       DW_AT_external
               Form:            DW_FORM_flag_present
             - Attribute:       DW_AT_decl_file
               Form:            DW_FORM_data1
             - Attribute:       DW_AT_decl_line
               Form:            DW_FORM_data1
             - Attribute:       DW_AT_location
               Form:            DW_FORM_exprloc
         - Code:            0x00000003
           Tag:             DW_TAG_base_type
           Children:        DW_CHILDREN_no
           Attributes:
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_encoding
               Form:            DW_FORM_data1
             - Attribute:       DW_AT_byte_size
               Form:            DW_FORM_data1
         - Code:            0x00000004
           Tag:             DW_TAG_variable
           Children:        DW_CHILDREN_no
           Attributes:
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_type
               Form:            DW_FORM_ref4
             - Attribute:       DW_AT_decl_file
               Form:            DW_FORM_data1
             - Attribute:       DW_AT_decl_line
               Form:            DW_FORM_data1
             - Attribute:       DW_AT_location
               Form:            DW_FORM_exprloc
         - Code:            0x00000005
           Tag:             DW_TAG_subprogram
           Children:        DW_CHILDREN_no
           Attributes:
             - Attribute:       DW_AT_low_pc
               Form:            DW_FORM_addr
             - Attribute:       DW_AT_high_pc
               Form:            DW_FORM_data4
             - Attribute:       DW_AT_frame_base
               Form:            DW_FORM_exprloc
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_decl_file
               Form:            DW_FORM_data1
             - Attribute:       DW_AT_decl_line
               Form:            DW_FORM_data1
             - Attribute:       DW_AT_type
               Form:            DW_FORM_ref4
             - Attribute:       DW_AT_external
               Form:            DW_FORM_flag_present
   debug_info:
     - Length:          113
       Version:         4
       AbbrOffset:      0
       AddrSize:        8
       Entries:
         - AbbrCode:        0x00000001
           Values:

llvm/test/tools/yaml2obj/ELF/DWARF/debug-abbrev.yaml

 --- !ELF
 FileHeader:
   Class:   ELFCLASS64
   Data:    ELFDATA2LSB
   Type:    ET_EXEC
   Machine: EM_X86_64
 DWARF:
   debug_abbrev:
+    - Table:
         - Code:     1
           Tag:      DW_TAG_compile_unit
           Children: DW_CHILDREN_yes
           Attributes:
             - Attribute: DW_AT_producer
               Form:      DW_FORM_strp
             - Attribute: DW_AT_language
               Form:      DW_FORM_data2
             - Attribute: DW_AT_name
               Form:      DW_FORM_strx
         - Code:     2
           Tag:      DW_TAG_subprogram
           Children: DW_CHILDREN_yes
           Attributes:
             - Attribute: DW_AT_low_pc
               Form:      DW_FORM_addr
             - Attribute: DW_AT_high_pc
               Form:      DW_FORM_addrx
         - Code:     3
           ## Test a reserved tag value.
           Tag:      0x06
           Children: DW_CHILDREN_no
           Attributes:
               ## Test an attribute value that is more than one byte.
             - Attribute: DW_AT_call_pc
               ## Test a form value that is more than one byte.
               Form:      0x81
               ## Test a reserved attribute value.
             - Attribute: 0x04
               ## Test a reserved form value.
               Form:      0x02
             - Attribute: 0x2020
               ## Test one special attribute form DW_FORM_implicit_const,
               ## who is followed by a SLEB128 value.
               Form:      DW_FORM_implicit_const
               Value:     12345678
 
 ## b) Generate the .debug_abbrev section from raw section content.
 
 # RUN: yaml2obj --docnum=2 %s -o %t2.o
 # RUN: llvm-readobj --sections --section-data %t2.o | \
 # RUN:   FileCheck -DADDRALIGN=0 -DSIZE=3 %s --check-prefixes=SHDR,ARBITRARY-CONTENT
 
 # ARBITRARY-CONTENT-NEXT: SectionData (
FileHeader:
   Type:    ET_EXEC
   Machine: EM_X86_64
 Sections:
   - Name: .debug_abbrev
     Type: SHT_PROGBITS
     Size: 0x10
 DWARF:
   debug_abbrev:
+    - Table:
         - Code:       1
           Tag:        DW_TAG_compile_unit
           Children:   DW_CHILDREN_no
           Attributes: []
 
 ## e) Test that yaml2obj emits an error message when both the "Content" and the
 ## "debug_abbrev" entry are specified at the same time.
 
 # RUN: not yaml2obj --docnum=5 %s 2>&1 | FileCheck %s --check-prefix=ERROR
 
 --- !ELF
 FileHeader:
   Class:   ELFCLASS64
   Data:    ELFDATA2LSB
   Type:    ET_EXEC
   Machine: EM_X86_64
 Sections:
   - Name:    .debug_abbrev
     Type:    SHT_PROGBITS
     Content: "00"
 DWARF:
   debug_abbrev:
+    - Table:
         - Code:       1
           Tag:        DW_TAG_compile_unit
           Children:   DW_CHILDREN_no
           Attributes: []
 
 ## f) Test that all the properties can be overridden by the section header when
 ## the "debug_abbrev" entry doesn't exist.
 
 # RUN: yaml2obj --docnum=6 %s -o %t6.o
 # RUN: llvm-readelf --sections %t6.o | FileCheck %s --check-prefix=OVERRIDDEN
 
 #      OVERRIDDEN: [Nr] Name          Type   Address          Off    Size   ES Flg Lk Inf Al
- Name:         .debug_abbrev
     Info:         1           ## 0 by default.
     AddressAlign: 2           ## 1 by default.
     Address:      0x2020      ## 0x00 by default.
     Offset:       0x50        ## 0x40 for the first section.
   - Name:         .sec        ## Linked by .debug_abbrev.
     Type:         SHT_STRTAB
 DWARF:
   debug_abbrev:
+    - Table:
         - Code:       1
           Tag:        DW_TAG_compile_unit
           Children:   DW_CHILDREN_no
           Attributes: []
 
 ## h) Test that yaml2obj automatically generates abbreviation codes for us.
 
 # RUN: yaml2obj --docnum=8 %s -o %t8.o
 # RUN: llvm-readelf --hex-dump=.debug_abbrev %t8.o | FileCheck %s --check-prefix=CODE
 
 #      CODE: 0x00000000 01110000 00022e00 0000042e 00000004
 ##                      ^-                                  abbreviation code ULEB128
 ##                                 ^-                       abbreviation code ULEB128
 ##                                            ^-            abbreviation code (ULEB128) 0x04
 ##                                                       ^- abbreviation code (ULEB128) 0x04
 ##
 # CODE-NEXT: 0x00000010 2e000000 052e0000 00062e00 0000
 ##                               ^-                     abbreviation code ULEB128
 ##                                          ^-          abbreviation code ULEB128
 
 --- !ELF
 FileHeader:
   Class:   ELFCLASS64
   Data:    ELFDATA2LSB
   Type:    ET_EXEC
   Machine: EM_X86_64
 DWARF:
   debug_abbrev:
+    - Table:
         - Tag:        DW_TAG_compile_unit
           Children:   DW_CHILDREN_no
           Attributes: []
         - Tag:        DW_TAG_subprogram
           Children:   DW_CHILDREN_no
           Attributes: []
         - Code:       4
           Tag:        DW_TAG_subprogram
           Children:   DW_CHILDREN_no
           Attributes: []
         - Code:       4
           Tag:        DW_TAG_subprogram
           Children:   DW_CHILDREN_no
           Attributes: []
         - Tag:        DW_TAG_subprogram
           Children:   DW_CHILDREN_no
           Attributes: []
         - Tag:        DW_TAG_subprogram
           Children:   DW_CHILDREN_no
           Attributes: []

llvm/test/tools/yaml2obj/ELF/DWARF/debug-info.yaml

 --- !ELF
 FileHeader:
   Class:   ELFCLASS64
   Data:    [[ENDIAN]]
   Type:    ET_EXEC
   Machine: EM_X86_64
 DWARF:
   debug_abbrev:
+    - Table:
         - Code:     1
           Tag:      DW_TAG_compile_unit
           Children: DW_CHILDREN_no
           Attributes:
             - Attribute: 0x01
               Form:      DW_FORM_addr           ## 0x01
             - Attribute: 0x01
               Form:      DW_FORM_block2         ## 0x03
             - Attribute: 0x01
               Form:      DW_FORM_block4         ## 0x04
             - Attribute: 0x01
               Form:      DW_FORM_data2          ## 0x05
             - Attribute: 0x01
               Form:      DW_FORM_data4          ## 0x06
             - Attribute: 0x01
               Form:      DW_FORM_data8          ## 0x07
             - Attribute: 0x01
               Form:      DW_FORM_string         ## 0x08
             - Attribute: 0x01
               Form:      DW_FORM_block          ## 0x09
             - Attribute: 0x01
               Form:      DW_FORM_block1         ## 0x0a
             - Attribute: 0x01
               Form:      DW_FORM_data1          ## 0x0b
             - Attribute: 0x01
               Form:      DW_FORM_flag           ## 0x0c
             - Attribute: 0x01
               Form:      DW_FORM_sdata          ## 0x0d
             - Attribute: 0x01
               Form:      DW_FORM_strp           ## 0x0e
             - Attribute: 0x01
               Form:      DW_FORM_udata          ## 0x0f
             - Attribute: 0x01
               Form:      DW_FORM_ref_addr       ## 0x10
             - Attribute: 0x01
               Form:      DW_FORM_ref1           ## 0x11
             - Attribute: 0x01
               Form:      DW_FORM_ref2           ## 0x12
             - Attribute: 0x01
               Form:      DW_FORM_ref4           ## 0x13
             - Attribute: 0x01
               Form:      DW_FORM_ref8           ## 0x14
             - Attribute: 0x01
               Form:      DW_FORM_ref_udata      ## 0x15
             - Attribute: 0x01
               Form:      DW_FORM_indirect       ## 0x16
             - Attribute: 0x01
               Form:      DW_FORM_sec_offset     ## 0x17
             - Attribute: 0x01
               Form:      DW_FORM_exprloc        ## 0x18
             - Attribute: 0x01
               Form:      DW_FORM_strx           ## 0x1a
             - Attribute: 0x01
               Form:      DW_FORM_addrx          ## 0x1b
             - Attribute: 0x01
               Form:      DW_FORM_ref_sup4       ## 0x1c
             - Attribute: 0x01
               Form:      DW_FORM_strp_sup       ## 0x1d
             - Attribute: 0x01
               Form:      DW_FORM_data16         ## 0x1e
             - Attribute: 0x01
               Form:      DW_FORM_line_strp      ## 0x1f
             - Attribute: 0x01
               Form:      DW_FORM_ref_sig8       ## 0x20
             - Attribute: 0x01
               Form:      DW_FORM_implicit_const ## 0x21
               Value:     0x01
             - Attribute: 0x01
               Form:      DW_FORM_loclistx       ## 0x22
             - Attribute: 0x01
               Form:      DW_FORM_rnglistx       ## 0x23
             - Attribute: 0x01
               Form:      DW_FORM_ref_sup8       ## 0x24
             - Attribute: 0x01
               Form:      DW_FORM_strx1          ## 0x25
             - Attribute: 0x01
               Form:      DW_FORM_strx2          ## 0x26
             - Attribute: 0x01
               Form:      DW_FORM_strx3          ## 0x27
             - Attribute: 0x01
               Form:      DW_FORM_strx4          ## 0x28
             - Attribute: 0x01
               Form:      DW_FORM_addrx1         ## 0x29
             - Attribute: 0x01
               Form:      DW_FORM_addrx2         ## 0x2a
             - Attribute: 0x01
               Form:      DW_FORM_addrx3         ## 0x2b
             - Attribute: 0x01
               Form:      DW_FORM_addrx4         ## 0x2c
   debug_info:
     - Length:     0x1234
       Version:    5
       UnitType:   DW_UT_type
       AbbrOffset: 0x1234
       AddrSize:   4
       Entries:
         - AbbrCode: 1
- Length:     0x1234
             - Value: 0x12               ## DW_FORM_strx1
             - Value: 0x1234             ## DW_FORM_strx2
             - Value: 0x123456           ## DW_FORM_strx3 (unimplemented)
             - Value: 0x12345678         ## DW_FORM_strx4
             - Value: 0x12               ## DW_FORM_addrx1
             - Value: 0x1234             ## DW_FORM_addrx2
             - Value: 0x123456           ## DW_FORM_addrx3 (unimplemented)
             - Value: 0x12345678         ## DW_FORM_addrx4
-    - Length:     0x1234
-      Version:    5
+    - Length:        0x1234
+      Version:       5
       ## Test another unit type.
-      UnitType:   DW_UT_compile
-      AbbrOffset: 0x1234
-      AddrSize:   4
+      UnitType:      DW_UT_compile
+      AbbrevTableID: 0
+      AbbrOffset:    0x1234
+      AddrSize:      4
       Entries:
         - AbbrCode: 0
           Values:   []
-    - Length:     0x5678
+    - Length:        0x5678
       ## Test DWARFv4
-      Version:    4
-      AbbrOffset: 0x5678
-      AddrSize:   4
+      Version:       4
+      AbbrevTableID: 0
+      AbbrOffset:    0x5678
+      AddrSize:      4
       Entries:
         - AbbrCode: 1
           Values:
             - Value: 0x12345678 ## DW_FORM_addr
             - BlockData:        ## DW_FORM_block2
                 - 0x12
                 - 0x34
 
FileHeader:
   Type:    ET_EXEC
   Machine: EM_X86_64
 Sections:
   - Name: .debug_info
     Type: SHT_PROGBITS
     Size: 0x10
 DWARF:
   debug_abbrev:
+    - Table:
         - Code:       1
           Tag:        DW_TAG_compile_unit
           Children:   DW_CHILDREN_no
           Attributes: []
   debug_info:
     - Length:     0x1234
       Version:    5
       UnitType:   DW_UT_type
       AbbrOffset: 0x1234
       Entries:    []
 
 ## e) Test that yaml2obj emits an error message when both the "Content" and the
 ## "debug_info" entry are specified at the same time.
 
 # RUN: not yaml2obj --docnum=5 %s 2>&1 | FileCheck %s --check-prefix=AMBIGUOUS-CONTENT
 
 --- !ELF
 FileHeader:
   Class:   ELFCLASS64
   Data:    ELFDATA2LSB
   Type:    ET_EXEC
   Machine: EM_X86_64
 Sections:
   - Name: .debug_info
     Type: SHT_PROGBITS
     Content: "00"
 DWARF:
   debug_abbrev:
+    - Table:
         - Code:       1
           Tag:        DW_TAG_compile_unit
           Children:   DW_CHILDREN_no
           Attributes: []
   debug_info:
     - Length:     0x1234
       Version:    5
       UnitType:   DW_UT_type
       AbbrOffset: 0x1234
       Entries:    []
 
 ## f) Test that all the properties can be overridden by the section header when
- Name:         .debug_info
     Info:         1           ## 0 by default.
     AddressAlign: 2           ## 0 by default.
     Address:      0x2020      ## 0x00 by default.
     Offset:       0x50        ## 0x40 for the first section.
   - Name:         .sec        ## Linked by .debug_info.
     Type:         SHT_STRTAB
 DWARF:
   debug_abbrev:
+    - Table:
         - Code:       1
           Tag:        DW_TAG_compile_unit
           Children:   DW_CHILDREN_no
           Attributes: []
   debug_info:
     - Length:     0x1234
       Version:    5
       UnitType:   DW_UT_type
       AbbrOffset: 0x1234
       Entries:
         - AbbrCode: 0
           Values:   []

 --- !ELF
 FileHeader:
   Class:   ELFCLASS32
   Data:    ELFDATA2LSB
   Type:    ET_EXEC
   Machine: EM_X86_64
 DWARF:
   debug_abbrev:
+    - Table:
         - Tag:        DW_TAG_compile_unit
           Children:   DW_CHILDREN_yes
           Attributes:
             - Attribute: DW_AT_low_pc
               Form:      DW_FORM_data4
             - Attribute: DW_AT_high_pc
               Form:      DW_FORM_data2
         - Tag:        DW_TAG_subprogram
           Children:   DW_CHILDREN_no
           Attributes:
             - Attribute: DW_AT_low_pc
               Form:      DW_FORM_data2
             - Attribute: DW_AT_high_pc
               Form:      DW_FORM_data4
   debug_info:
     - Length:     0x1234
       Version:    5
       UnitType:   DW_UT_type
       AbbrOffset: 0x1234
       Entries:
         ## Test that yaml2obj emits values when the abbrev code is specified.
         - AbbrCode: 2
           Values:
             - Value: 0x1234
             - Value: 0x87654321
         ## Test that yaml2obj emits values when the abbrev code is specified to
         ## be lower than the first abbrev.
         - AbbrCode: 1
           Values:
             - Value: 0x87654321
             - Value: 0x1234
         ## Test that yaml2obj ignores the contents of entries with abbrev code 0.
         - AbbrCode: 0
           Values:
             - Value: 0x1234
 
 ## i) Test that yaml2obj reports an error when 'debug_info' has values in its
 ## entries but 'debug_abbrev' doesn't have enough attributes for them.
 
 # RUN: not yaml2obj --docnum=10 %s -o %t10.o 2>&1 | \
 # RUN:   FileCheck %s --check-prefixes=ERROR
 
 # ERROR: yaml2obj: error: abbrev code must be less than or equal to the number of entries in abbreviation table
 
 --- !ELF
 FileHeader:
   Class:   ELFCLASS64
   Data:    ELFDATA2LSB
   Type:    ET_EXEC
   Machine: EM_X86_64
 DWARF:
+  debug_abbrev:
+    - ID: 0
   debug_info:
     - Length:     0x1234
       Version:    5
       UnitType:   DW_UT_type
       AbbrOffset: 0x1234
       Entries:
         - AbbrCode: 1
           Values:
FileHeader:
   Machine: EM_X86_64
 DWARF:
   debug_str:
     - "clang version 10.0.0 "
     - "hello.c"
     - "/home/v/x/llvm/playground"
     - "main"
   debug_abbrev:
+    - Table:
         - Code:     1
           Tag:      DW_TAG_compile_unit
           Children: DW_CHILDREN_yes
           Attributes:
             - Attribute: DW_AT_producer
               Form:      DW_FORM_strp
             - Attribute: DW_AT_language
               Form:      DW_FORM_data2
             - Attribute: DW_AT_name
               Form:      DW_FORM_strp
             - Attribute: DW_AT_stmt_list
               Form:      DW_FORM_sec_offset
             - Attribute: DW_AT_comp_dir
               Form:      DW_FORM_strp
             - Attribute: DW_AT_low_pc
               Form:      DW_FORM_addr
             - Attribute: DW_AT_high_pc
               Form:      DW_FORM_data4
         - Code: 2
           Tag:  DW_TAG_subprogram
           Children: DW_CHILDREN_no
           Attributes:
             - Attribute: DW_AT_low_pc
               Form:      DW_FORM_addr
             - Attribute: DW_AT_high_pc
               Form:      DW_FORM_data4
             - Attribute: DW_AT_name
               Form:      DW_FORM_strp
   debug_info:
     - Version:    4
       AbbrOffset: 0x00
       Entries:
         - AbbrCode: 1
           Values:
             - Value: 0x00   ## DW_AT_producer [DW_FORM_strp]
             - Value: 0x0c   ## DW_LANG_C99, DW_AT_language [DW_FORM_data2]
FileHeader:
   Class:   ELFCLASS[[BITS]]
   Data:    ELFDATA2LSB
   Type:    ET_EXEC
   Machine: EM_X86_64
 DWARF:
   debug_info:
     - Version:    4
       AbbrOffset: 0x00
+
+## n) Test that yaml2obj emits an error message when a compilation unit doesn't have
+## an associated abbrev table.
+
+# RUN: not yaml2obj --docnum=16 %s 2>&1 | FileCheck %s --check-prefix=MISSING-ABBREV
+
+# MISSING-ABBREV: yaml2obj: error: cannot find abbrev table whose ID is 0
+
+--- !ELF
+FileHeader:
+  Class:   ELFCLASS64
+  Data:    ELFDATA2LSB
+  Type:    ET_EXEC
+  Machine: EM_X86_64
+DWARF:
+  debug_info:
+    - Version:    4
+      AbbrOffset: 0x00
+      Entries:
+        - AbbrCode: 1
+          Values:
+            - Value: 0x1234
+
+## o) Test that yaml2obj emits an error message when multiple abbrev tables are assigned
+## the same ID.
+
+# RUN: not yaml2obj --docnum=17 %s 2>&1 | FileCheck %s --check-prefix=ID-COLLISION
+
+# ID-COLLISION: yaml2obj: error: the ID (1) of abbrev table with index 1 has been used
+
+--- !ELF
+FileHeader:
+  Class:   ELFCLASS64
+  Data:    ELFDATA2LSB
+  Type:    ET_EXEC
+  Machine: EM_X86_64
+DWARF:
+  debug_abbrev:
+    - ID: 1
+    - ID: 1

llvm/tools/obj2yaml/dwarf2yaml.cpp

 #include "llvm/DebugInfo/DWARF/DWARFContext.h"
 #include "llvm/DebugInfo/DWARF/DWARFDebugArangeSet.h"
 #include "llvm/DebugInfo/DWARF/DWARFDebugRangeList.h"
 #include "llvm/DebugInfo/DWARF/DWARFFormValue.h"
 #include "llvm/DebugInfo/DWARF/DWARFSection.h"
 #include "llvm/ObjectYAML/DWARFYAML.h"
 
 #include <algorithm>
 
 using namespace llvm;
 
 void dumpDebugAbbrev(DWARFContext &DCtx, DWARFYAML::Data &Y) {
   auto AbbrevSetPtr = DCtx.getDebugAbbrev();
   if (AbbrevSetPtr) {
+    uint64_t AbbrevTableID = 0;
     for (auto AbbrvDeclSet : *AbbrevSetPtr) {
+      DWARFYAML::AbbrevTable AbbrevTable;
       for (auto AbbrvDecl : AbbrvDeclSet.second) {
         DWARFYAML::Abbrev Abbrv;
         Abbrv.Code = AbbrvDecl.getCode();
         Abbrv.Tag = AbbrvDecl.getTag();
         Abbrv.Children = AbbrvDecl.hasChildren() ? dwarf::DW_CHILDREN_yes
                                                  : dwarf::DW_CHILDREN_no;
         for (auto Attribute : AbbrvDecl.attributes()) {
           DWARFYAML::AttributeAbbrev AttAbrv;
           AttAbrv.Attribute = Attribute.Attr;
           AttAbrv.Form = Attribute.Form;
           if (AttAbrv.Form == dwarf::DW_FORM_implicit_const)
             AttAbrv.Value = Attribute.getImplicitConstValue();
           Abbrv.Attributes.push_back(AttAbrv);
         }
-        Y.AbbrevDecls.push_back(Abbrv);
+        AbbrevTable.Table.push_back(Abbrv);
+        AbbrevTable.ID = AbbrevTableID ++;
       }
+      Y.DebugAbbrev.push_back(AbbrevTable);
     }
   }
 }
 
 void dumpDebugStrings(DWARFContext &DCtx, DWARFYAML::Data &Y) {
   StringRef RemainingTable = DCtx.getDWARFObj().getStrSection();
   while (RemainingTable.size() > 0) {
     auto SymbolPair = RemainingTable.split('\0');

 void dumpDebugInfo(DWARFContext &DCtx, DWARFYAML::Data &Y) {
   for (const auto &CU : DCtx.compile_units()) {
     DWARFYAML::Unit NewUnit;
     NewUnit.Format = CU->getFormat();
     NewUnit.Length = CU->getLength();
     NewUnit.Version = CU->getVersion();
     if (NewUnit.Version >= 5)
       NewUnit.Type = (dwarf::UnitType)CU->getUnitType();
+    const DWARFDebugAbbrev *DebugAbbrev = DCtx.getDebugAbbrev();
+    NewUnit.AbbrevTableID =
+        std::distance(
+            DebugAbbrev->begin(),
+            std::find_if(
+                DebugAbbrev->begin(), DebugAbbrev->end(),
+                [&](const std::pair<uint64_t, DWARFAbbreviationDeclarationSet>
+                        &P) {
+                  return P.first == CU->getAbbreviations()->getOffset();
+                }));
     NewUnit.AbbrOffset = CU->getAbbreviations()->getOffset();
     NewUnit.AddrSize = CU->getAddressByteSize();
     for (auto DIE : CU->dies()) {
       DWARFYAML::Entry NewEntry;
       DataExtractor EntryData = CU->getDebugInfoExtractor();
       uint64_t offset = DIE.getOffset();
 
       assert(EntryData.isValidOffset(offset) && "Invalid DIE Offset");

llvm/unittests/DebugInfo/DWARF/DWARFDebugInfoTest.cpp

TEST(DWARFDebugInfo, TestChildIteratorsOnInvalidDie) {
   auto end = Invalid.end();
   EXPECT_FALSE(begin->isValid());
   EXPECT_FALSE(end->isValid());
   EXPECT_EQ(begin, end);
 }
 
 TEST(DWARFDebugInfo, TestEmptyChildren) {
   const char *yamldata = "debug_abbrev:\n"
-                         "  - Code:            0x00000001\n"
-                         "    Tag:             DW_TAG_compile_unit\n"
-                         "    Children:        DW_CHILDREN_yes\n"
-                         "    Attributes:\n"
+                         "  - Table:\n"
+                         "      - Code:            0x00000001\n"
+                         "        Tag:             DW_TAG_compile_unit\n"
+                         "        Children:        DW_CHILDREN_yes\n"
+                         "        Attributes:\n"
                          "debug_info:\n"
                          "  - Version:         4\n"
                          "    AbbrOffset:      0\n"
                          "    AddrSize:        8\n"
                          "    Entries:\n"
                          "      - AbbrCode:        0x00000001\n"
                          "        Values:\n"
                          "      - AbbrCode:        0x00000000\n"
TEST(DWARFDebugInfo, TestDwarfVerifyInvalidCURef) {
   // the compile unit itself.
 
   const char *yamldata = R"(
     debug_str:
       - ''
       - /tmp/main.c
       - main
     debug_abbrev:
+      - Table:
           - Code:            0x00000001
             Tag:             DW_TAG_compile_unit
             Children:        DW_CHILDREN_yes
             Attributes:
               - Attribute:       DW_AT_name
                 Form:            DW_FORM_strp
           - Code:            0x00000002
             Tag:             DW_TAG_subprogram
             Children:        DW_CHILDREN_no
             Attributes:
               - Attribute:       DW_AT_name
                 Form:            DW_FORM_strp
               - Attribute:       DW_AT_type
                 Form:            DW_FORM_ref4
     debug_info:
       - Length:          22
         Version:         4
         AbbrOffset:      0
         AddrSize:        8
         Entries:
           - AbbrCode:        0x00000001
             Values:
TEST(DWARFDebugInfo, TestDwarfVerifyInvalidRefAddr) {
   // Create a single compile unit with a single function that has an invalid
   // DW_AT_type with an invalid .debug_info offset in its DW_FORM_ref_addr.
   const char *yamldata = R"(
     debug_str:
       - ''
       - /tmp/main.c
       - main
     debug_abbrev:
+      - Table:
           - Code:            0x00000001
             Tag:             DW_TAG_compile_unit
             Children:        DW_CHILDREN_yes
             Attributes:
               - Attribute:       DW_AT_name
                 Form:            DW_FORM_strp
           - Code:            0x00000002
             Tag:             DW_TAG_subprogram
             Children:        DW_CHILDREN_no
             Attributes:
               - Attribute:       DW_AT_name
                 Form:            DW_FORM_strp
               - Attribute:       DW_AT_type
                 Form:            DW_FORM_ref_addr
     debug_info:
       - Length:          22
         Version:         4
         AbbrOffset:      0
         AddrSize:        8
         Entries:
           - AbbrCode:        0x00000001
             Values:

 TEST(DWARFDebugInfo, TestDwarfVerifyInvalidRanges) {
   // Create a single compile unit with a DW_AT_ranges whose section offset
   // isn't valid.
   const char *yamldata = R"(
     debug_str:
       - ''
       - /tmp/main.c
     debug_abbrev:
+      - Table:
           - Code:            0x00000001
             Tag:             DW_TAG_compile_unit
             Children:        DW_CHILDREN_no
             Attributes:
               - Attribute:       DW_AT_name
                 Form:            DW_FORM_strp
               - Attribute:       DW_AT_ranges
                 Form:            DW_FORM_sec_offset
     debug_info:
       - Length:          16
         Version:         4
         AbbrOffset:      0
         AddrSize:        8
         Entries:
           - AbbrCode:        0x00000001
             Values:

 TEST(DWARFDebugInfo, TestDwarfVerifyInvalidRnglists) {
   // Create a single compile unit with a DW_AT_ranges whose section offset
   // isn't valid.
   const char *yamldata = R"(
     debug_str:
       - ''
       - /tmp/main.c
     debug_abbrev:
+      - Table:
           - Code:            0x00000001
             Tag:             DW_TAG_compile_unit
             Children:        DW_CHILDREN_no
             Attributes:
               - Attribute:       DW_AT_name
                 Form:            DW_FORM_strp
               - Attribute:       DW_AT_ranges
                 Form:            DW_FORM_sec_offset
     debug_info:
       - Length:          17
         Version:         5
         UnitType:        DW_UT_compile
         AbbrOffset:      0
         AddrSize:        8
         Entries:
           - AbbrCode:        0x00000001

 TEST(DWARFDebugInfo, TestDwarfVerifyInvalidStmtList) {
   // Create a single compile unit with a DW_AT_stmt_list whose section offset
   // isn't valid.
   const char *yamldata = R"(
     debug_str:
       - ''
       - /tmp/main.c
     debug_abbrev:
+      - Table:
           - Code:            0x00000001
             Tag:             DW_TAG_compile_unit
             Children:        DW_CHILDREN_no
             Attributes:
               - Attribute:       DW_AT_name
                 Form:            DW_FORM_strp
               - Attribute:       DW_AT_stmt_list
                 Form:            DW_FORM_sec_offset
     debug_info:
       - Length:          16
         Version:         4
         AbbrOffset:      0
         AddrSize:        8
         Entries:
           - AbbrCode:        0x00000001
             Values:

 
 TEST(DWARFDebugInfo, TestDwarfVerifyInvalidStrp) {
   // Create a single compile unit with a single function that has an invalid
   // DW_FORM_strp for the DW_AT_name.
   const char *yamldata = R"(
     debug_str:
       - ''
     debug_abbrev:
+      - Table:
           - Code:            0x00000001
             Tag:             DW_TAG_compile_unit
             Children:        DW_CHILDREN_no
             Attributes:
               - Attribute:       DW_AT_name
                 Form:            DW_FORM_strp
     debug_info:
       - Length:          12
         Version:         4
         AbbrOffset:      0
         AddrSize:        8
         Entries:
           - AbbrCode:        0x00000001
             Values:
TEST(DWARFDebugInfo, TestDwarfVerifyInvalidRefAddrBetween) {
   // Create a single compile unit with a single function that has a DW_AT_type
   // with a valid .debug_info offset, but the offset is between two DIEs.
   const char *yamldata = R"(
     debug_str:
       - ''
       - /tmp/main.c
       - main
     debug_abbrev:
+      - Table:
           - Code:            0x00000001
             Tag:             DW_TAG_compile_unit
             Children:        DW_CHILDREN_yes
             Attributes:
               - Attribute:       DW_AT_name
                 Form:            DW_FORM_strp
           - Code:            0x00000002
             Tag:             DW_TAG_subprogram
             Children:        DW_CHILDREN_no
             Attributes:
               - Attribute:       DW_AT_name
                 Form:            DW_FORM_strp
               - Attribute:       DW_AT_type
                 Form:            DW_FORM_ref_addr
     debug_info:
       - Length:          22
         Version:         4
         AbbrOffset:      0
         AddrSize:        8
         Entries:
           - AbbrCode:        0x00000001
             Values:

 TEST(DWARFDebugInfo, TestDwarfVerifyInvalidLineSequence) {
   // Create a single compile unit whose line table has a sequence in it where
   // the address decreases.
   StringRef yamldata = R"(
     debug_str:
       - ''
       - /tmp/main.c
     debug_abbrev:
+      - Table:
           - Code:            0x00000001
             Tag:             DW_TAG_compile_unit
             Children:        DW_CHILDREN_no
             Attributes:
               - Attribute:       DW_AT_name
                 Form:            DW_FORM_strp
               - Attribute:       DW_AT_stmt_list
                 Form:            DW_FORM_sec_offset
     debug_info:
       - Length:          16
         Version:         4
         AbbrOffset:      0
         AddrSize:        8
         Entries:
           - AbbrCode:        0x00000001
             Values:

 TEST(DWARFDebugInfo, TestDwarfVerifyInvalidLineFileIndex) {
   // Create a single compile unit whose line table has a line table row with
   // an invalid file index.
   StringRef yamldata = R"(
     debug_str:
       - ''
       - /tmp/main.c
     debug_abbrev:
+      - Table:
           - Code:            0x00000001
             Tag:             DW_TAG_compile_unit
             Children:        DW_CHILDREN_no
             Attributes:
               - Attribute:       DW_AT_name
                 Form:            DW_FORM_strp
               - Attribute:       DW_AT_stmt_list
                 Form:            DW_FORM_sec_offset
     debug_info:
       - Length:          16
         Version:         4
         AbbrOffset:      0
         AddrSize:        8
         Entries:
           - AbbrCode:        0x00000001
             Values:

 TEST(DWARFDebugInfo, TestDwarfVerifyInvalidLineTablePorlogueDirIndex) {
   // Create a single compile unit whose line table has a prologue with an
   // invalid dir index.
   StringRef yamldata = R"(
     debug_str:
       - ''
       - /tmp/main.c
     debug_abbrev:
+      - Table:
           - Code:            0x00000001
             Tag:             DW_TAG_compile_unit
             Children:        DW_CHILDREN_no
             Attributes:
               - Attribute:       DW_AT_name
                 Form:            DW_FORM_strp
               - Attribute:       DW_AT_stmt_list
                 Form:            DW_FORM_sec_offset
     debug_info:
       - Length:          16
         Version:         4
         AbbrOffset:      0
         AddrSize:        8
         Entries:
           - AbbrCode:        0x00000001
             Values:

 TEST(DWARFDebugInfo, TestDwarfVerifyDuplicateFileWarning) {
   // Create a single compile unit whose line table has a prologue with an
   // invalid dir index.
   StringRef yamldata = R"(
     debug_str:
       - ''
       - /tmp/main.c
     debug_abbrev:
+      - Table:
           - Code:            0x00000001
             Tag:             DW_TAG_compile_unit
             Children:        DW_CHILDREN_no
             Attributes:
               - Attribute:       DW_AT_name
                 Form:            DW_FORM_strp
               - Attribute:       DW_AT_stmt_list
                 Form:            DW_FORM_sec_offset
     debug_info:
       - Length:          16
         Version:         4
         AbbrOffset:      0
         AddrSize:        8
         Entries:
           - AbbrCode:        0x00000001
             Values:
TEST(DWARFDebugInfo, TestDwarfVerifyCUDontShareLineTable) {
   // Create a two compile units where both compile units share the same
   // DW_AT_stmt_list value and verify we report the error correctly.
   StringRef yamldata = R"(
     debug_str:
       - ''
       - /tmp/main.c
       - /tmp/foo.c
     debug_abbrev:
+      - Table:
           - Code:            0x00000001
             Tag:             DW_TAG_compile_unit
             Children:        DW_CHILDREN_no
             Attributes:
               - Attribute:       DW_AT_name
                 Form:            DW_FORM_strp
               - Attribute:       DW_AT_stmt_list
                 Form:            DW_FORM_sec_offset
     debug_info:
       - Length:          16
         Version:         4
         AbbrOffset:      0
         AddrSize:        8
         Entries:
           - AbbrCode:        0x00000001
             Values:
               - Value:           0x0000000000000001
               - Value:           0x0000000000000000
       - Length:          16
         Version:         4
+        AbbrevTableID:   0
         AbbrOffset:      0
         AddrSize:        8
         Entries:
           - AbbrCode:        0x00000001
             Values:
               - Value:           0x000000000000000D
               - Value:           0x0000000000000000
     debug_line:
TEST(DWARFDebugInfo, TestDwarfVerifyCURangesIncomplete) {
   // address range of the function. The verification should fail due to
   // the CU ranges not containing all of the address ranges of all of the
   // functions.
   StringRef yamldata = R"(
     debug_str:
       - ''
       - /tmp/main.c
     debug_abbrev:
+      - Table:
           - Code:            0x00000001
             Tag:             DW_TAG_compile_unit
             Children:        DW_CHILDREN_yes
             Attributes:
               - Attribute:       DW_AT_low_pc
                 Form:            DW_FORM_addr
               - Attribute:       DW_AT_high_pc
                 Form:            DW_FORM_addr
               - Attribute:       DW_AT_name
                 Form:            DW_FORM_strp
           - Code:            0x00000002
             Tag:             DW_TAG_subprogram
             Children:        DW_CHILDREN_no
             Attributes:
               - Attribute:       DW_AT_low_pc
                 Form:            DW_FORM_addr
               - Attribute:       DW_AT_high_pc
                 Form:            DW_FORM_addr
     debug_info:
       - Length:          46
         Version:         4
         AbbrOffset:      0
         AddrSize:        8
         Entries:
           - AbbrCode:        0x00000001
             Values:
TEST(DWARFDebugInfo, TestDwarfVerifyLexicalBlockRanges) {
   // Create a single compile unit with a single function that has a lexical
   // block whose address range is not contained in the function address range.
   StringRef yamldata = R"(
     debug_str:
       - ''
       - /tmp/main.c
       - main
     debug_abbrev:
+      - Table:
           - Code:            0x00000001
             Tag:             DW_TAG_compile_unit
             Children:        DW_CHILDREN_yes
             Attributes:
               - Attribute:       DW_AT_name
                 Form:            DW_FORM_strp
           - Code:            0x00000002
             Tag:             DW_TAG_subprogram
             Children:        DW_CHILDREN_yes
             Attributes:
               - Attribute:       DW_AT_name
                 Form:            DW_FORM_strp
               - Attribute:       DW_AT_low_pc
                 Form:            DW_FORM_addr
               - Attribute:       DW_AT_high_pc
                 Form:            DW_FORM_addr
           - Code:            0x00000003
             Tag:             DW_TAG_lexical_block
             Children:        DW_CHILDREN_no
             Attributes:
               - Attribute:       DW_AT_low_pc
                 Form:            DW_FORM_addr
               - Attribute:       DW_AT_high_pc
                 Form:            DW_FORM_addr
     debug_info:
       - Length:          52
         Version:         4
         AbbrOffset:      0
         AddrSize:        8
         Entries:
           - AbbrCode:        0x00000001
             Values:
TEST(DWARFDebugInfo, TestDwarfVerifyOverlappingFunctionRanges) {
   // address ranges.
   StringRef yamldata = R"(
     debug_str:
       - ''
       - /tmp/main.c
       - main
       - foo
     debug_abbrev:
+      - Table:
           - Code:            0x00000001
             Tag:             DW_TAG_compile_unit
             Children:        DW_CHILDREN_yes
             Attributes:
               - Attribute:       DW_AT_name
                 Form:            DW_FORM_strp
           - Code:            0x00000002
             Tag:             DW_TAG_subprogram
             Children:        DW_CHILDREN_no
             Attributes:
               - Attribute:       DW_AT_name
                 Form:            DW_FORM_strp
               - Attribute:       DW_AT_low_pc
                 Form:            DW_FORM_addr
               - Attribute:       DW_AT_high_pc
                 Form:            DW_FORM_addr
     debug_info:
       - Length:          55
         Version:         4
         AbbrOffset:      0
         AddrSize:        8
         Entries:
           - AbbrCode:        0x00000001
             Values:
TEST(DWARFDebugInfo, TestDwarfVerifyOverlappingLexicalBlockRanges) {
   // Create a single compile unit with a one function that has two lexical
   // blocks with overlapping address ranges.
   StringRef yamldata = R"(
     debug_str:
       - ''
       - /tmp/main.c
       - main
     debug_abbrev:
+      - Table:
           - Code:            0x00000001
             Tag:             DW_TAG_compile_unit
             Children:        DW_CHILDREN_yes
             Attributes:
               - Attribute:       DW_AT_low_pc
                 Form:            DW_FORM_addr
               - Attribute:       DW_AT_high_pc
                 Form:            DW_FORM_addr
               - Attribute:       DW_AT_name
                 Form:            DW_FORM_strp
           - Code:            0x00000002
             Tag:             DW_TAG_subprogram
             Children:        DW_CHILDREN_yes
             Attributes:
               - Attribute:       DW_AT_name
                 Form:            DW_FORM_strp
               - Attribute:       DW_AT_low_pc
                 Form:            DW_FORM_addr
               - Attribute:       DW_AT_high_pc
                 Form:            DW_FORM_addr
           - Code:            0x00000003
             Tag:             DW_TAG_lexical_block
             Children:        DW_CHILDREN_no
             Attributes:
               - Attribute:       DW_AT_low_pc
                 Form:            DW_FORM_addr
               - Attribute:       DW_AT_high_pc
                 Form:            DW_FORM_addr
     debug_info:
       - Length:          85
         Version:         4
         AbbrOffset:      0
         AddrSize:        8
         Entries:
           - AbbrCode:        0x00000001
             Values:
TEST(DWARFDebugInfo, TestDwarfVerifyInvalidDIERange) {
   // Create a single compile unit with a single function that has an invalid
   // address range where the high PC is smaller than the low PC.
   StringRef yamldata = R"(
     debug_str:
       - ''
       - /tmp/main.c
       - main
     debug_abbrev:
+      - Table:
           - Code:            0x00000001
             Tag:             DW_TAG_compile_unit
             Children:        DW_CHILDREN_yes
             Attributes:
               - Attribute:       DW_AT_name
                 Form:            DW_FORM_strp
           - Code:            0x00000002
             Tag:             DW_TAG_subprogram
             Children:        DW_CHILDREN_no
             Attributes:
               - Attribute:       DW_AT_name
                 Form:            DW_FORM_strp
               - Attribute:       DW_AT_low_pc
                 Form:            DW_FORM_addr
               - Attribute:       DW_AT_high_pc
                 Form:            DW_FORM_addr
     debug_info:
       - Length:          34
         Version:         4
         AbbrOffset:      0
         AddrSize:        8
         Entries:
           - AbbrCode:        0x00000001
             Values:
TEST(DWARFDebugInfo, TestDwarfVerifyElidedDoesntFail) {
   // ensure that verification succeeds.
   StringRef yamldata = R"(
     debug_str:
       - ''
       - /tmp/main.c
       - main
       - elided
     debug_abbrev:
+      - Table:
           - Code:            0x00000001
             Tag:             DW_TAG_compile_unit
             Children:        DW_CHILDREN_yes
             Attributes:
               - Attribute:       DW_AT_low_pc
                 Form:            DW_FORM_addr
               - Attribute:       DW_AT_high_pc
                 Form:            DW_FORM_addr
               - Attribute:       DW_AT_name
                 Form:            DW_FORM_strp
           - Code:            0x00000002
             Tag:             DW_TAG_subprogram
             Children:        DW_CHILDREN_no
             Attributes:
               - Attribute:       DW_AT_name
                 Form:            DW_FORM_strp
               - Attribute:       DW_AT_low_pc
                 Form:            DW_FORM_addr
               - Attribute:       DW_AT_high_pc
                 Form:            DW_FORM_addr
     debug_info:
       - Length:          71
         Version:         4
         AbbrOffset:      0
         AddrSize:        8
         Entries:
           - AbbrCode:        0x00000001
             Values:
TEST(DWARFDebugInfo, TestDwarfVerifyNestedFunctions) {
   // to the DWARF standard.
   StringRef yamldata = R"(
     debug_str:
       - ''
       - /tmp/main.c
       - main
       - nested
     debug_abbrev:
+      - Table:
           - Code:            0x00000001
             Tag:             DW_TAG_compile_unit
             Children:        DW_CHILDREN_yes
             Attributes:
               - Attribute:       DW_AT_low_pc
                 Form:            DW_FORM_addr
               - Attribute:       DW_AT_high_pc
                 Form:            DW_FORM_addr
               - Attribute:       DW_AT_name
                 Form:            DW_FORM_strp
           - Code:            0x00000002
             Tag:             DW_TAG_subprogram
             Children:        DW_CHILDREN_yes
             Attributes:
               - Attribute:       DW_AT_name
                 Form:            DW_FORM_strp
               - Attribute:       DW_AT_low_pc
                 Form:            DW_FORM_addr
               - Attribute:       DW_AT_high_pc
                 Form:            DW_FORM_addr
     debug_info:
       - Length:          73
         Version:         4
         AbbrOffset:      0
         AddrSize:        8
         Entries:
           - AbbrCode:        0x00000001
             Values:

llvm/unittests/DebugInfo/DWARF/DWARFDieTest.cpp

 using namespace llvm::dwarf;
 using object::SectionedAddress;
 
 namespace {
 
 TEST(DWARFDie, getLocations) {
   const char *yamldata = R"(
     debug_abbrev:
+      - Table:
           - Code:            0x00000001
             Tag:             DW_TAG_compile_unit
             Children:        DW_CHILDREN_no
             Attributes:
               - Attribute:       DW_AT_location
                 Form:            DW_FORM_sec_offset
               - Attribute:       DW_AT_data_member_location
                 Form:            DW_FORM_exprloc
               - Attribute:       DW_AT_vtable_elem_location
                 Form:            DW_FORM_sec_offset
               - Attribute:       DW_AT_call_data_location
                 Form:            DW_FORM_sec_offset
     debug_info:
       - Version:         5
         UnitType:        DW_UT_compile
         AbbrOffset:      0
         AddrSize:        4
         Entries:
           - AbbrCode:        0x00000001
             Values:

llvm/unittests/DebugInfo/GSYM/GSYMTest.cpp

TEST(GSYMTest, TestDWARFFunctionWithAddresses) {
   // converted to DWARF correctly. The function's address range is in where
   // DW_AT_low_pc and DW_AT_high_pc are both addresses.
   StringRef yamldata = R"(
   debug_str:
     - ''
     - /tmp/main.c
     - main
   debug_abbrev:
+    - Table:
         - Code:            0x00000001
           Tag:             DW_TAG_compile_unit
           Children:        DW_CHILDREN_yes
           Attributes:
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_low_pc
               Form:            DW_FORM_addr
             - Attribute:       DW_AT_high_pc
               Form:            DW_FORM_addr
             - Attribute:       DW_AT_language
               Form:            DW_FORM_data2
         - Code:            0x00000002
           Tag:             DW_TAG_subprogram
           Children:        DW_CHILDREN_no
           Attributes:
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_low_pc
               Form:            DW_FORM_addr
             - Attribute:       DW_AT_high_pc
               Form:            DW_FORM_addr
   debug_info:
     - Length:          52
       Version:         4
       AbbrOffset:      0
       AddrSize:        8
       Entries:
         - AbbrCode:        0x00000001
           Values:
TEST(GSYMTest, TestDWARFFunctionWithAddressAndOffset) {
   // converted to DWARF correctly. The function's address range is in where
   // DW_AT_low_pc is an address and the DW_AT_high_pc is an offset.
   StringRef yamldata = R"(
   debug_str:
     - ''
     - /tmp/main.c
     - main
   debug_abbrev:
+    - Table:
         - Code:            0x00000001
           Tag:             DW_TAG_compile_unit
           Children:        DW_CHILDREN_yes
           Attributes:
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_low_pc
               Form:            DW_FORM_addr
             - Attribute:       DW_AT_high_pc
               Form:            DW_FORM_data4
             - Attribute:       DW_AT_language
               Form:            DW_FORM_data2
         - Code:            0x00000002
           Tag:             DW_TAG_subprogram
           Children:        DW_CHILDREN_no
           Attributes:
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_low_pc
               Form:            DW_FORM_addr
             - Attribute:       DW_AT_high_pc
               Form:            DW_FORM_data4
   debug_info:
     - Length:          44
       Version:         4
       AbbrOffset:      0
       AddrSize:        8
       Entries:
         - AbbrCode:        0x00000001
           Values:
TEST(GSYMTest, TestDWARFStructMethodNoMangled) {
   StringRef yamldata = R"(
   debug_str:
     - ''
     - /tmp/main.c
     - Foo
     - dump
     - this
   debug_abbrev:
+    - Table:
         - Code:            0x00000001
           Tag:             DW_TAG_compile_unit
           Children:        DW_CHILDREN_yes
           Attributes:
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_low_pc
               Form:            DW_FORM_addr
             - Attribute:       DW_AT_high_pc
               Form:            DW_FORM_addr
             - Attribute:       DW_AT_language
               Form:            DW_FORM_data2
         - Code:            0x00000002
           Tag:             DW_TAG_structure_type
           Children:        DW_CHILDREN_yes
           Attributes:
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
         - Code:            0x00000003
           Tag:             DW_TAG_subprogram
           Children:        DW_CHILDREN_yes
           Attributes:
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_low_pc
               Form:            DW_FORM_addr
             - Attribute:       DW_AT_high_pc
               Form:            DW_FORM_addr
         - Code:            0x00000004
           Tag:             DW_TAG_formal_parameter
           Children:        DW_CHILDREN_no
           Attributes:
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_type
               Form:            DW_FORM_ref4
             - Attribute:       DW_AT_artificial
               Form:            DW_FORM_flag_present
   debug_info:
     - Length:          68
       Version:         4
       AbbrOffset:      0
       AddrSize:        8
       Entries:
         - AbbrCode:        0x00000001
           Values:
TEST(GSYMTest, TestDWARFTextRanges) {
   StringRef yamldata = R"(
   debug_str:
     - ''
     - /tmp/main.c
     - main
     - dead_stripped
     - dead_stripped2
   debug_abbrev:
+    - Table:
         - Code:            0x00000001
           Tag:             DW_TAG_compile_unit
           Children:        DW_CHILDREN_yes
           Attributes:
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_low_pc
               Form:            DW_FORM_addr
             - Attribute:       DW_AT_high_pc
               Form:            DW_FORM_data4
             - Attribute:       DW_AT_language
               Form:            DW_FORM_data2
         - Code:            0x00000002
           Tag:             DW_TAG_subprogram
           Children:        DW_CHILDREN_no
           Attributes:
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_low_pc
               Form:            DW_FORM_addr
             - Attribute:       DW_AT_high_pc
               Form:            DW_FORM_data4
   debug_info:
     - Length:          78
       Version:         4
       AbbrOffset:      0
       AddrSize:        8
       Entries:
         - AbbrCode:        0x00000001
           Values:
TEST(GSYMTest, TestDWARFInlineInfo) {
   // DWARF.
   StringRef yamldata = R"(
   debug_str:
     - ''
     - /tmp/main.c
     - main
     - inline1
   debug_abbrev:
+    - Table:
         - Code:            0x00000001
           Tag:             DW_TAG_compile_unit
           Children:        DW_CHILDREN_yes
           Attributes:
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_low_pc
               Form:            DW_FORM_addr
             - Attribute:       DW_AT_high_pc
               Form:            DW_FORM_data4
             - Attribute:       DW_AT_language
               Form:            DW_FORM_data2
             - Attribute:       DW_AT_stmt_list
               Form:            DW_FORM_sec_offset
         - Code:            0x00000002
           Tag:             DW_TAG_subprogram
           Children:        DW_CHILDREN_yes
           Attributes:
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_low_pc
               Form:            DW_FORM_addr
             - Attribute:       DW_AT_high_pc
               Form:            DW_FORM_data4
         - Code:            0x00000003
           Tag:             DW_TAG_inlined_subroutine
           Children:        DW_CHILDREN_no
           Attributes:
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_low_pc
               Form:            DW_FORM_addr
             - Attribute:       DW_AT_high_pc
               Form:            DW_FORM_data4
             - Attribute:       DW_AT_call_file
               Form:            DW_FORM_data4
             - Attribute:       DW_AT_call_line
               Form:            DW_FORM_data4
   debug_info:
     - Length:          74
       Version:         4
       AbbrOffset:      0
       AddrSize:        8
       Entries:
         - AbbrCode:        0x00000001
           Values:
TEST(GSYMTest, TestDWARFNoLines) {
   debug_str:
     - ''
     - '/tmp/main.c'
     - lines_no_decl
     - lines_with_decl
     - no_lines_no_decl
     - no_lines_with_decl
   debug_abbrev:
+    - Table:
         - Code:            0x00000001
           Tag:             DW_TAG_compile_unit
           Children:        DW_CHILDREN_yes
           Attributes:
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_low_pc
               Form:            DW_FORM_addr
             - Attribute:       DW_AT_high_pc
               Form:            DW_FORM_data4
             - Attribute:       DW_AT_language
               Form:            DW_FORM_data2
             - Attribute:       DW_AT_stmt_list
               Form:            DW_FORM_sec_offset
         - Code:            0x00000002
           Tag:             DW_TAG_subprogram
           Children:        DW_CHILDREN_no
           Attributes:
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_low_pc
               Form:            DW_FORM_addr
             - Attribute:       DW_AT_high_pc
               Form:            DW_FORM_data4
         - Code:            0x00000003
           Tag:             DW_TAG_subprogram
           Children:        DW_CHILDREN_no
           Attributes:
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_low_pc
               Form:            DW_FORM_addr
             - Attribute:       DW_AT_high_pc
               Form:            DW_FORM_data4
             - Attribute:       DW_AT_decl_file
               Form:            DW_FORM_data1
             - Attribute:       DW_AT_decl_line
               Form:            DW_FORM_data1
   debug_info:
     - Length:          103
       Version:         4
       AbbrOffset:      0
       AddrSize:        8
       Entries:
         - AbbrCode:        0x00000001
           Values:
TEST(GSYMTest, TestDWARFDeadStripAddr4) {
   //
   // 0x00000041:   DW_TAG_subprogram
   //                 DW_AT_name ("stripped3")
   //                 DW_AT_low_pc (0x0000000000004000)
   //                 DW_AT_high_pc  (0x0000000000003fff)
   //
   // 0x0000004e:   NULL
 
 
   StringRef yamldata = R"(
   debug_str:
     - ''
     - '/tmp/main.c'
     - main
     - stripped1
     - stripped2
     - stripped3
   debug_abbrev:
+    - Table:
         - Code:            0x00000001
           Tag:             DW_TAG_compile_unit
           Children:        DW_CHILDREN_yes
           Attributes:
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_low_pc
               Form:            DW_FORM_addr
             - Attribute:       DW_AT_high_pc
               Form:            DW_FORM_data4
             - Attribute:       DW_AT_language
               Form:            DW_FORM_data2
         - Code:            0x00000002
           Tag:             DW_TAG_subprogram
           Children:        DW_CHILDREN_no
           Attributes:
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_low_pc
               Form:            DW_FORM_addr
             - Attribute:       DW_AT_high_pc
               Form:            DW_FORM_data4
         - Code:            0x00000003
           Tag:             DW_TAG_subprogram
           Children:        DW_CHILDREN_no
           Attributes:
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_low_pc
               Form:            DW_FORM_addr
             - Attribute:       DW_AT_high_pc
               Form:            DW_FORM_addr
   debug_info:
     - Length:          75
       Version:         4
       AbbrOffset:      0
       AddrSize:        4
       Entries:
         - AbbrCode:        0x00000001
           Values:
TEST(GSYMTest, TestDWARFDeadStripAddr8) {
   debug_str:
     - ''
     - '/tmp/main.c'
     - main
     - stripped1
     - stripped2
     - stripped3
   debug_abbrev:
+    - Table:
         - Code:            0x00000001
           Tag:             DW_TAG_compile_unit
           Children:        DW_CHILDREN_yes
           Attributes:
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_low_pc
               Form:            DW_FORM_addr
             - Attribute:       DW_AT_high_pc
               Form:            DW_FORM_data4
             - Attribute:       DW_AT_language
               Form:            DW_FORM_data2
         - Code:            0x00000002
           Tag:             DW_TAG_subprogram
           Children:        DW_CHILDREN_no
           Attributes:
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_low_pc
               Form:            DW_FORM_addr
             - Attribute:       DW_AT_high_pc
               Form:            DW_FORM_data4
         - Code:            0x00000003
           Tag:             DW_TAG_subprogram
           Children:        DW_CHILDREN_no
           Attributes:
             - Attribute:       DW_AT_name
               Form:            DW_FORM_strp
             - Attribute:       DW_AT_low_pc
               Form:            DW_FORM_addr
             - Attribute:       DW_AT_high_pc
               Form:            DW_FORM_addr
   debug_info:
     - Length:          103
       Version:         4
       AbbrOffset:      0
       AddrSize:        8
       Entries:
         - AbbrCode:        0x00000001
           Values: