> This PR makes ClassDesc.ofDescriptor return the shared constant for primitive
> descriptor strings ("I" etc..), and leverages this further by refactoring
> `MethodTypeDescImpl.ofDescriptor` to avoid the intermediate substring for
> primitives.
>
> Microbenchmarks results look good with expected speedups and allocation
> reductions any time a primitive is part of the descriptor string, and a
> non-significant cost otherwise:
>
>
> Name (descString)
> Cnt Base Error Test Error Unit Change
> ClassDescFactories.ofDescriptor Ljava/lang/Object;
> 6 13,941 ± 1,643 14,071 ± 1,333 ns/op 0,99x (p = 0,681 )
> :gc.alloc.rate.norm
> 16,000 ± 0,000 16,000 ± 0,000 B/op 1,00x (p = 0,617 )
> ClassDescFactories.ofDescriptor V
> 6 9,212 ± 1,045 1,405 ± 0,049 ns/op 6,55x (p = 0,000*)
> :gc.alloc.rate.norm
> 48,000 ± 0,000 0,000 ± 0,000 B/op 0,00x (p = 0,000*)
> ClassDescFactories.ofDescriptor I
> 6 9,009 ± 0,035 1,431 ± 0,192 ns/op 6,30x (p = 0,000*)
> :gc.alloc.rate.norm
> 48,000 ± 0,000 0,000 ± 0,000 B/op 0,00x (p = 0,000*)
> MethodTypeDescFactories.ofDescriptor (Ljava/lang/Object;Ljava/lang/String;)I
> 6 182,050 ± 4,333 141,644 ± 2,685 ns/op 1,29x (p = 0,000*)
> :gc.alloc.rate.norm
> 360,001 ± 0,000 264,001 ± 0,000 B/op 0,73x (p = 0,000*)
> MethodTypeDescFactories.ofDescriptor ()V
> 6 17,169 ± 2,008 9,915 ± 0,018 ns/op 1,73x (p = 0,000*)
> :gc.alloc.rate.norm
> 120,000 ± 0,000 104,000 ± 0,000 B/op 0,87x (p = 0,000*)
> MethodTypeDescFactories.ofDescriptor ([IJLjava/lang/String;Z)Ljava/util/List;
> 6 270,372 ± 3,624 217,050 ± 3,170 ns/op 1,25x (p = 0,000*)
> :gc.alloc.rate.norm
> 520,002 ± 0,000 328,001 ± 0,000 B/op 0,63x (p = 0,000*)
> MethodTypeDescFactories.ofDescriptor ()[Ljava/lang/String;
> 6 35,036 ± 0,351 36,010 ± 3,882 ns/op 0,97x (p = 0,1...
Claes Redestad has updated the pull request incrementally with one additional
commit since the last revision:
Fix ClassDescTest; remove redundant validation performed by
ReferenceClassDescImpl
-------------
Changes:
- all: https://git.openjdk.org/jdk/pull/18971/files
- new: https://git.openjdk.org/jdk/pull/18971/files/96aa846b..257dc547
Webrevs:
- full: https://webrevs.openjdk.org/?repo=jdk&pr=18971&range=01
- incr: https://webrevs.openjdk.org/?repo=jdk&pr=18971&range=00-01
Stats: 14 lines in 2 files changed: 1 ins; 11 del; 2 mod
Patch: https://git.openjdk.org/jdk/pull/18971.diff
Fetch: git fetch https://git.openjdk.org/jdk.git pull/18971/head:pull/18971
PR: https://git.openjdk.org/jdk/pull/18971
