[llvm-dev] CodeView layering

[Zachary Turner via llvm-dev]

It seems a little strange conceptually that object depends on
BitcodeReader. Is it possible to break that dependency?
On Thu, Mar 29, 2018 at 4:11 PM David Blaikie <dblaikie at gmail.com> wrote:

> On Mon, Mar 26, 2018 at 4:52 PM David Blaikie <dblaikie at gmail.com> wrote:
>
>> On Thu, Mar 22, 2018 at 12:55 PM Reid Kleckner <rnk at google.com> wrote:
>>
>>> On Wed, Mar 21, 2018 at 11:31 AM David Blaikie <dblaikie at gmail.com>
>>> wrote:
>>>
>>>> I'm looking at fixing some layering violations in LLVM & came across a
>>>> few in the CodeView handling, specifically:
>>>>
>>>> lib/MC/MCCodeView includes several llvm/DebugInfo/CodeView headers
>>>>   I guess MC could be made dependent on DebugInfoCodeView? But probably
>>>> these things should be sunk into BinaryFormat as is the case for DWARF
>>>> features used by MC?
>>>>
>>>
>>> I'd be OK with that. We could very easily introduce true link
>>> dependencies on that library in the near future.
>>>
>>
>> OK - added the LLVMBuild.txt change in r328595
>>
>
> Hmm, not perfect - this creates a bit of a circular dependency:
>
> llvm-tblgen
> MC
> DebugInfo/CodeView
> Object
> Bitcode/Reader
> IR (including lib/IR/AttributesCompatFunc.inc)
> llvm-tblgen (to generate AttributesCompatFunc.inc)
>
> This is just a specific path shown by the internal build system - no doubt
> there are other tblgen files in LLVM IR, etc.
>
> So I guess still need to split up DebugInfo/CodeView (assuming the bits
> needed by MC don't depend on Object)? Any suggestions? Sink it into
> BinaryFormat or name a new library?
>
> (it's quite a few headers by the looks of it: CodeView.h, Line.h,
> SymbolRecord.h, CodeViewTypes.def, CodeViewSymbols.def,
> CodeViewRegisters.def, TypeIndex.h, CVRecord.h, CodeViewError.h,
> RecordSerialization.h - maybe some of those aren't needed, if they're
> excessive includes or the like (they tend to seep in all over the place))
>
>
>>
>>
>>> include/llvm/Object/COFF.h includes
>>>> include/llvm/DebugInfo/CodeView/CVDebugRecord.h
>>>>   Also seems like this could/should/needs to be sunk into BinaryFormat?
>>>>
>>>
>>> These things are really more PE/PDB related than CodeView. They are in
>>> the wrong place. I'd ask Saleem to help find a new home. Object or
>>> BinaryFormats seem OK to me.
>>>
>>
>> Moved it to libObject (r328593) for now which is at least correct - if
>> someone thinks it'd be more suited to BinaryFormat, I'm happy to move it or
>> they can.
>>
>>
>>>
>>>
>>>> I'm open to ideas & happy to do the work, or help in any way that might
>>>> be useful.
>>>>
>>>> Thanks,
>>>> - Dave
>>>>
>>>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20180329/4f2cbe32/attachment.html>