System.Runtime.Metadata IL reader

[vzarytovskii]

Description

New IL reader which uses S.R.M, which is faster and more correct. Continuing on top of Will's(@TIHan) work.

Checklist

• Performance tests (not CI-based, but synthetic ones).
• Added a compiler switch (off-by-default) which would select old or new reader
• Test cases added (separate CI leg which will be using --test: flag (see below)
• --test:* flag which will run both readers and deep-compare their results
• CI step which will be using said --test flag
• Release notes entry updated

[vzarytovskii]

Oh well, this didn't go well:

error FS0193: The module/namespace 'RuntimeHelpers' from compilation unit 'FSharp.Core' did not contain the val 'ValLinkagePartialKey(EnumerateTryWith)'

when compiling self

[github-actions]

❗ Release notes required

@vzarytovskii,

Caution

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Change path	Release notes path	Description
src/Compiler	docs/release-notes/.FSharp.Compiler.Service/8.0.400.md	No release notes found or release notes format is not correct