Functions returning non-nullable records of 2 fields can now return
them as separate values on 2 registers. This postpones and sometimes
eliminates creation of record instances. As other unboxing
optimizations of return values, this optimization is only
performed in AOT.
Pair of values for an unboxed record are represented using
kPairOfTagged representation, which can be now used for the input of
Return and for the output of StaticCall/InstanceCall
PolymorphicInstanceCall/DispatchTableCall instructions.
In order to combine separate values for Return, a new MakePair
instruction is added. Extracting separate values from the result of
a call is implemented using existing ExtractNthOutput instruction.
Benchmarks (AOT mode):
MultipleReturns.Forwarded.Record +45-57%
MultipleReturns.Forwarded.RecordNamed +43-57%
MultipleReturns.NotInlined.Record +58-79%
MultipleReturns.NotInlined.RecordNamed +53-76%
TEST=runtime/tests/vm/dart/records_return_value_unboxing_il_test.dart
TEST=benchmarks/MultipleReturns/dart/MultipleReturns.dart
Issue: https://github.com/dart-lang/sdk/issues/49719
Change-Id: I7117b19a134c1db0ba5117a1ef093867f9ba20e2
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/269100
Commit-Queue: Alexander Markov <alexmarkov@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
Alexander Markov
a9c11acd25