[wasm] Selectively strip the Name section of the wasm blob

[CoffeeFlux]

Currently, this section takes up about 150K without ICU and 550K with ICU. For a minimal sample we should get rid of everything other than a handful of functions. For the normal build we should get rid of the ICU symbols other than the ones we call directly since they are of little benefit to us in stack traces. See https://github.com/WebAssembly/design/blob/master/BinaryEncoding.md#name-section

[Dotnet-GitSync-Bot]

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[lewing]

@CoffeeFlux it is much more useful to speak in terms of compressed size for metrics like this.

[lewing]

Stripping all the debug information via wasm-opt --strip-debug which removes more than the name section produces:

dotnet.wasm	Case
2818531	full uncompressed
2281278	stripped uncompressed
537253	difference uncompressed
883475	brotli with debug
776250	brotli stripped
107225	brotli difference

Which is worth noting in the sense that the names/debug information clearly compressed more than the bulk of dotnet.wasm

[lewing]

@kg thoughts on how difficult it would be to strip all names matching a regex while preserving the rest?

[kg]

@kg thoughts on how difficult it would be to strip all names matching a regex while preserving the rest?

Very easy, we'd eat an extra byte or two of filler for the stripped names worst case but it'll compress out

[lewing]

@tqiu8 please prioritize

[tqiu8]

This is no longer an issue due to #43951, which uses wasm-opt from emscripten to strip out the custom section including names. This will not affect the debugger performance.