[wasm] EmccCompile: Add support for compiling sequentially

[radical]

Add support for user specified assemblies that should always be compiled
sequentially. This would be useful for cases where some assemblies fail to compile
because emcc runs out of memory when compiled in parallel with other assemblies.

New:

 - @(WasmAssemblyToAOTSequentially) - Filenames of assemblies to always compile (to .o) sequentially

[ghost]

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Issue Details

---

This adds support for two cases:

1. Compiling an assembly in parallel fails due to getting oomkill'ed.
   In this case, it will get compiled again but not in parallel with
   anything else.

2. User specified assemblies that should always be compiled
   sequentially.

This would be useful for cases where some assemblies fail to compile
because emcc runs out of memory.

New:

 - $(WasmRetrySequentiallyIfNeeded) - Retry assembly compilation to .o files sequentially, if needed.
One such case could be if the compiler got killed due to OOM.
Defaults to true.
- @(WasmAssemblyToAOTSequentially) - Filenames of assemblies to always compile (to .o) sequentially

Author:	radical
Assignees:	-
Labels:	arch-wasm, area-Build-mono
Milestone:	-

[radical]

/azp run runtime-wasm

[azure-pipelines]

Azure Pipelines successfully started running 1 pipeline(s).

[vargaz]

Not sure that a build system should retry failing commands. Would a setting limiting the amount of parallelism, like make's -j argument work ?

[radical]

Not sure that a build system should retry failing commands. Would a setting limiting the amount of parallelism, like make's -j argument work ?

Using only -j like argument would limit that for all the files, instead of a few, which is the problem that I was trying to solve here. Like when some assemblies run out of memory when aot'ed at the same time as others, but compile fine when aot'ed by themselves.

I have removed the retry mechanism here.

[radical]

/azp run runtime-wasm

[azure-pipelines]

Azure Pipelines successfully started running 1 pipeline(s).

[radical]

/azp run runtime-wasm

[azure-pipelines]

Azure Pipelines successfully started running 1 pipeline(s).

[lewing]

@ankit do you still think this is useful?

[ghost]

This pull request has been automatically marked no-recent-activity because it has not had any activity for 14 days. It will be closed if no further activity occurs within 14 more days. Any new comment (by anyone, not necessarily the author) will remove no-recent-activity.

[ghost]

Draft Pull Request was automatically closed for 30 days of inactivity. Please let us know if you'd like to reopen it.