[llvm] [CodeView] Support LF_CLASS2 and friends (PR #228761)

[via llvm-commits]

github-actions[bot] wrote:

<!--PREMERGE ADVISOR COMMENT: Windows-->
# :window: Windows x64 Test Results

* 143312 tests passed
* 3438 tests skipped
* 1 test failed

## Failed Tests
(click on a test name to see its output)

### LLVM
<details>
<summary>LLVM.tools/llvm-pdbutil/unknown-records.test</summary>

```
Exit Code: 1

Command Output (stdout):
--
# RUN: at line 2
c:\_work\llvm-project\llvm-project\build\bin\llvm-pdbutil.exe dump -all C:\_work\llvm-project\llvm-project\llvm\test\tools\llvm-pdbutil/Inputs/unknown-record.obj | c:\_work\llvm-project\llvm-project\build\bin\filecheck.exe C:\_work\llvm-project\llvm-project\llvm\test\tools\llvm-pdbutil\unknown-records.test
# executed command: 'c:\_work\llvm-project\llvm-project\build\bin\llvm-pdbutil.exe' dump -all 'C:\_work\llvm-project\llvm-project\llvm\test\tools\llvm-pdbutil/Inputs/unknown-record.obj'
# note: command had no output on stdout or stderr
# executed command: 'c:\_work\llvm-project\llvm-project\build\bin\filecheck.exe' 'C:\_work\llvm-project\llvm-project\llvm\test\tools\llvm-pdbutil\unknown-records.test'
# .---command stderr------------
# | C:\_work\llvm-project\llvm-project\llvm\test\tools\llvm-pdbutil\unknown-records.test:3:10: error: CHECK: expected string not found in input
# | ; CHECK: UNKNOWN RECORD (0x1609)
# |          ^
# | <stdin>:1:1: note: scanning from here
# | 
# | ^
# | <stdin>:112:40: note: possible intended match here
# |  return type = 0x0074 (int), # args = 2, param list = 0x1001
# |                                        ^
# | 
# | Input file: <stdin>
# | Check file: C:\_work\llvm-project\llvm-project\llvm\test\tools\llvm-pdbutil\unknown-records.test
# | 
# | -dump-input=help explains the following input dump.
# | 
# | Input was:
# | <<<<<<
# |            1:  
# | check:3'0    {   search range start (exclusive)
# | check:3'1        error: no match found in search range
# |            2:  
# |            3:  Summary  
# |            4: ============================================================ 
# |            5:  Dumping this stream is not valid for object files 
# |            6:  
# |            .
# |            .
# |            .
# |          107:  referent = 0x0670 (char*), mode = pointer, opts = None, kind = ptr64 
# |          108: 0x1001 | LF_ARGLIST [size = 16] 
# |          109:  0x0074 (int): `int` 
# |          110:  0x1000: `char**` 
# |          111: 0x1002 | LF_PROCEDURE [size = 16] 
# |          112:  return type = 0x0074 (int), # args = 2, param list = 0x1001 
# | check:3'2                                            ?                       possible intended match
# |          113:  calling conv = cdecl, options = None 
# |          114: 0x1003 | LF_FUNC_ID [size = 20] 
# |          115:  name = main, type = 0x1002, parent scope = <no type> 
# |          116: 0x1004 | LF_STRUCTURE2 [size = 48] `NS::Foo` 
# |          117:  unique name: `.?AUFoo at NS@@` 
# |            .
# |            .
# |            .
# |          221: ============================================================ 
# |          222:  Dumping this stream is not valid for object files 
# |          223:  
# |          224:  Section Map  
# |          225: ============================================================ 
# |          226:  Dumping this stream is not valid for object files 
# | check:3'3                                                        } search range end (exclusive)
# | >>>>>>
# `-----------------------------
# error: command failed with exit status: 1

--

```
</details>

If these failures are unrelated to your changes (for example tests are broken or flaky at HEAD), please open an issue at https://github.com/llvm/llvm-project/issues and add the `infrastructure` label.

https://github.com/llvm/llvm-project/pull/228761