llvm dev - May 2021 - [LLParser] Remove deplibs related defines and functions

On 2021-05-26, Chris Lattner via llvm-dev wrote:
>On May 19, 2021, at 11:51 PM, Xuanda Yang via llvm-dev <llvm-dev at
lists.llvm.org> wrote:
>>
>> Hi folks!
>>
>> I plan to remove some outdated defines and functions related to deplibs
in LLParser/LLLexer as the comment suggested they should be removed in 4.0 (e.g,
see:
https://github.com/llvm/llvm-project/blob/57ea5d4f48754b9b3470fceb197a56ed938ddc02/llvm/lib/AsmParser/LLParser.cpp#L465
<https://github.com/llvm/llvm-project/blob/57ea5d4f48754b9b3470fceb197a56ed938ddc02/llvm/lib/AsmParser/LLParser.cpp#L465>).
>>
>> The purposed change will delete several functions and you can take a
look at https://reviews.llvm.org/D102763
<https://reviews.llvm.org/D102763>. The removal itself is pretty trivial,
but as Saleem suggested in the review, it may have potential impact to any
down-stream projects. So I am posting this here to make sure we have a good
understanding on the impact before the actual removal.
>
>Seems ok to me, if it causes a problem for anyone the fix in the .ll file
will be trivial.
>
>-Chris
I tried this cleanup in 2020, but a point was raised that this can be
used to read old bitcode files. See https://reviews.llvm.org/D73422

> I tried this cleanup in 2020, but a point was raised that this can be
> used to read old bitcode files. See https://reviews.llvm.org/D73422 
D73422 removed both textual IR parsing and bitcode reading.  Textual IR
never really had any backward-compatibility guarantees.  The new patch
removes only textual IR parsing, it does not remove bitcode reading; it
should be fine to do this.
--paulr