[wasm] browser profiler

[pavelsavara]

reporting both interpreter, AOT and some Javascript calls directly to chrome dev tools via performance.measure()

Chrome

FireFox

Profiler

• mono profiler infrastructure allows to register multiple profiler plugins. This an implementation of one of them.
• is implemented in src\mono\mono\profiler\browser.c only for WASM platform
• it registers method enter/leave events.
• There is no filter for the methods, so it would set flags and trigger for all managed methods.
• it calls out into browser profiler via performance.measure API
• interp is always calling the profiler callback, when installed
• AOT compiler will emit icall to profiler for each flagged method
  • this means that profiler is running as part of JIT process in the AOT compiler.
• JavaScript code of startup and interop methods are annotated

Usage

<PropertyGroup>
  <WasmProfilers>browser;</WasmProfilers>
</PropertyGroup>

And

await dotnet
    .withConfig({
        browserProfilerOptions: {}
    })
    .run()

And start profiling in browser dev tools

Notes

• alternatively we could implement plugin into EventPipe, which is itself mono profiler plugin. This solution is simpler.
• when enabled: simple wasm to js call per event, method name building on first call to a method
• no runtime overhead when not enabled in user project. Just some bytes for the new code in wasm.

Future work

• enable method filtering by name, namespace, ...
• max depth
• start and end time
• start and end method
• report GC events and class loading and config to enable/disable it

Changes

• new profiler browser.c
• JS startup annotation
• new static module libmono-profiler-browser.a it is always linked into dotnet.wasm in both Debug and Release configurations
• profiler statically linked into AOT compiler on WASM target
• updated advanced sample to enable profiler
• cache for method names on JS side
• fix for MonoAOTCompiler build task to pass --profiler argument to AOT compiler

Contributes to #76316

[ghost]

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Issue Details

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Author:	pavelsavara
Assignees:	pavelsavara
Labels:	arch-wasm, area-System.Runtime.InteropServices.JavaScript
Milestone:	8.0.0

[radical]

incomplete review, just sharing some comments.

[lambdageek]

LGTM except there seems to be some copy/paste errors in the invoke-cs methods