Experiment: enable parallel optimization by default

[majocha]

Apart from deterministic builds just make it the default. Let's see if it breaks.

EDIT: Also enable parallel IL gen.

[github-actions]

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[vzarytovskii]

One thing to check - whether deterministic builds are default. If yes, it won't have any effect - debug builds don't run optimizer, and nobody really turning determinism off for production builds.

[majocha]

One thing to check - whether deterministic builds are default. If yes, it won't have any effect - debug builds don't run optimizer, and nobody really turning determinism off for production builds.

fsharp/src/Compiler/Driver/CompilerConfig.fs

Line 817 in 753cb84

deterministic = false

It is off by default. I guess there are some legitimate dev scenarios when speeding up release build is useful, for example building release to run tests.

[vzarytovskii]

One thing to check - whether deterministic builds are default. If yes, it won't have any effect - debug builds don't run optimizer, and nobody really turning determinism off for production builds.

fsharp/src/Compiler/Driver/CompilerConfig.fs

Line 817 in 753cb84

deterministic = false

It is off by default. I guess there are some legitimate dev scenarios when speeding up release build is useful, for example building release to run tests.

It might be off by default in the compiler, but on by default in msbuild.

[majocha]

One thing to check - whether deterministic builds are default. If yes, it won't have any effect - debug builds don't run optimizer, and nobody really turning determinism off for production builds.

fsharp/src/Compiler/Driver/CompilerConfig.fs

Line 817 in 753cb84

deterministic = false

It is off by default. I guess there are some legitimate dev scenarios when speeding up release build is useful, for example building release to run tests.

It might be off by default in the compiler, but on by default in msbuild.

Yes, needs checking. Looks like <Fsc> task is aligned with the defaults:

fsharp/src/FSharp.Build/Fsc.fs

Line 35 in bd346da

let mutable deterministic: bool = false