Change IL Emit invoke path to use function pointers and OpCodes.Calli

[steveharter]

Currently, the invoke fast-path generates IL using either call or callvirt. If this is changed to use calli and function pointers, it is possible to cache the generated dynamic method and use it for all such calls to the same signature. This reduces the memory footprint and makes calling subsequent but different methods faster since there would essentially be a hashtable look upon the signature instead of generating a new method.

In addition, it will be used to support invoke against a function pointer via #75347.

Items to consider:

• Sharing of instance methods across different reference Types.
• Virtual functions (see ldvirtftn).

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Issue Details

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Currently, the invoke fast-path generates IL using either call or callvirt. If this is changed to use calli and function pointers, it is possible to cache the generated dynamic method and use it for all such calls to the same signature. This reduces the memory footprint and makes calling subsequent but different methods faster since there would essentially be a hashtable look upon the signature instead of generating a new method.

In addition, it will be used to support invoke against a function pointer via #75347.

Items to consider:

• Sharing of instance methods across different reference Types.
• Virtual functions (see ldvirtftn).

Author:	steveharter
Assignees:	steveharter
Labels:	area-System.Reflection, tenet-performance
Milestone:	8.0.0

[ericstj]

@steveharter are we still planning this, or is it superseded by #112994?