This is a reland of commit 6b3d1752fa
Fixes b/235734143
TEST=runtime/tests/vm/dart/await_in_custom_zone_test.dart
Original change's description:
> [vm] More efficient 'await' of not Future and completed _Future
>
> When awaiting a value which is not a Future or a completed
> built-in _Future, 'await' implementation can bypass heavyweight
> _Future/_FutureListener machinery and schedule micro-tasks directly.
>
> Benchmarks:
> JIT, x64:
> AsyncLiveVars.* +46-54% (bigger is better)
> Calls.AwaitAsyncCall -46% (less is better)
> Calls.AwaitAsyncCallInstanceTargetPolymorphic -46%
> Calls.AwaitAsyncCallClosureTargetPolymorphic -45%
> Calls.AwaitFutureOrCallInstanceTargetPolymorphicManyAwaits -45%
> Calls.AwaitFutureOrCall -60%
> Calls.AwaitFutureOrCallInstanceTargetPolymorphic -60%
> Calls.AwaitFutureOrCallClosureTargetPolymorphic -59%
>
> JIT, ia32:
> AsyncLiveVars.* +43-52% (bigger is better)
> Calls.AwaitAsyncCall -42% (less is better)
> Calls.AwaitAsyncCallInstanceTargetPolymorphic -42%
> Calls.AwaitAsyncCallClosureTargetPolymorphic -41%
> Calls.AwaitFutureOrCallInstanceTargetPolymorphicManyAwaits -39%
> Calls.AwaitFutureOrCall -55%
> Calls.AwaitFutureOrCallInstanceTargetPolymorphic -54%
> Calls.AwaitFutureOrCallClosureTargetPolymorphic -53%
>
> JIT, arm:
> AsyncLiveVars.* +64-71% (bigger is better)
> Calls.AwaitAsyncCallInstanceTargetPolymorphic -51% (less is better)
> Calls.AwaitAsyncCallClosureTargetPolymorphic -47%
> Calls.AwaitFutureOrCallInstanceTargetPolymorphicManyAwaits -48%
> Calls.AwaitFutureOrCall -64%
> Calls.AwaitFutureOrCallInstanceTargetPolymorphic -64%
> Calls.AwaitFutureOrCallClosureTargetPolymorphic -59%
>
> JIT, arm64:
> AsyncLiveVars.* +65-78% (bigger is better)
> Calls.AwaitAsyncCall -51% (less is better)
> Calls.AwaitAsyncCallInstanceTargetPolymorphic -51%
> Calls.AwaitAsyncCallClosureTargetPolymorphic -50%
> Calls.AwaitFutureOrCallInstanceTargetPolymorphicManyAwaits -49%
> Calls.AwaitFutureOrCall -69%
> Calls.AwaitFutureOrCallInstanceTargetPolymorphic -68%
> Calls.AwaitFutureOrCallClosureTargetPolymorphic -67%
>
> AOT, x64:
> AsyncLiveVars.* +55-61% (bigger is better)
> Calls.AwaitAsyncCall -47% (less is better)
> Calls.AwaitAsyncCallInstanceTargetPolymorphic -46%
> Calls.AwaitAsyncCallClosureTargetPolymorphic -47%
> Calls.AwaitFutureOrCallInstanceTargetPolymorphicManyAwaits -46%
> Calls.AwaitFutureOrCall -59%
> Calls.AwaitFutureOrCallInstanceTargetPolymorphic -59%
> Calls.AwaitFutureOrCallClosureTargetPolymorphic -58%
>
> AOT, arm:
> AsyncLiveVars.* 54-66% (bigger is better)
> Calls.AwaitAsyncCall -46-51% (less is better)
> Calls.AwaitAsyncCallInstanceTargetPolymorphic -46-50%
> Calls.AwaitAsyncCallClosureTargetPolymorphic -46-52%
> Calls.AwaitFutureOrCallInstanceTargetPolymorphicManyAwaits -45-50%
> Calls.AwaitFutureOrCall -63-68%
> Calls.AwaitFutureOrCallInstanceTargetPolymorphic -63-66%
> Calls.AwaitFutureOrCallClosureTargetPolymorphic -63-67%
>
> AOT, arm64:
> AsyncLiveVars.* +53-66% (bigger is better)
> Calls.AwaitAsyncCall -50-51% (less is better)
> Calls.AwaitAsyncCallInstanceTargetPolymorphic -50%
> Calls.AwaitAsyncCallClosureTargetPolymorphic -50-51%
> Calls.AwaitFutureOrCallInstanceTargetPolymorphicManyAwaits -49-50%
> Calls.AwaitFutureOrCall -66-68%
> Calls.AwaitFutureOrCallInstanceTargetPolymorphic -66-68%
> Calls.AwaitFutureOrCallClosureTargetPolymorphic -63-67%
>
> TEST=ci
> Issue: https://github.com/dart-lang/sdk/issues/48378
>
> Change-Id: I65e3702fcd816ee3fee876ff442b9887c035b1ec
> Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/243102
> Reviewed-by: Lasse Nielsen <lrn@google.com>
> Commit-Queue: Alexander Markov <alexmarkov@google.com>
Change-Id: I245984ace1c768fdcba58dfdd6aa46e52126be4e
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/248442
Commit-Queue: Alexander Markov <alexmarkov@google.com>
Reviewed-by: Lasse Nielsen <lrn@google.com>
Reviewed-by: Slava Egorov <vegorov@google.com>
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