Use bison for ilasm parser generator

[hez2010]

Supersedes #89704. Fixes #4776.

Bison for Windows: https://github.com/lexxmark/winflexbison
For other platforms: https://www.gnu.org/software/bison

To generate the asmparse.cpp: yacc asmparse.y -o asmparse.cpp (or win_bison asmparse.y -o asmparse.cpp)

/cc: @TIHan @JulieLeeMSFT

[TIHan]

Thank you @hez2010 ! Will review this soon.

[TIHan]

So far this looks good. Going to look at it a bit deeper.

[TIHan]

/azp run runtime-coreclr ilasm

[azure-pipelines]

Azure Pipelines successfully started running 1 pipeline(s).

[AaronRobinsonMSFT]

I have deleted the asmparse.grammar file as it's no longer being maintained since 2021.

I question this is no longer being maintained. What IL grammar changes have we introduced since 2021 that haven't made it in?

[hez2010]

What IL grammar changes have we introduced since 2021 that haven't made it in?

For example, byreflike on generics.

[AaronRobinsonMSFT]

What IL grammar changes have we introduced since 2021 that haven't made it in?

For example, byreflike on generics.

I wrote that feature and it was updated. See byreflike under typarAttrib.

[hez2010]

I wrote that feature and it was updated. See byreflike under typarAttrib.

Okay I see, sorry for missed that. I can bring it back but note that there's no public tool that can auto generate the asmparser.grammar file now.

[TIHan]

Thanks for your work @hez2010 ! Glad to see this be done.

I'll make a follow-up PR that adds a small README.md on how to generate the parser.