On Fri, 23 Aug 2024 12:34:17 GMT, Claes Redestad <redes...@openjdk.org> wrote:
> This PR refactors SwitchBootstraps so that extra EnumDescs and classes are
> only passed into bootstraps when needed. Benchmarking shows that in many
> cases these are not needed, and avoiding passing them (via binding in the
> lists via `MethodHandle::insertArguments`) avoids some auxiliary MH
> combinator generation during bootstrap.
>
> Additional cleanups and refactoring further reduce bootstrap overhead and
> number of classes loaded.
src/java.base/share/classes/java/lang/runtime/SwitchBootstraps.java line 85:
> 83: private static final boolean previewEnabled =
> PreviewFeatures.isEnabled();
> 84:
> 85: private static final ClassDesc CD_BiPredicate =
> referenceClassDesc(BiPredicate.class);
This can use `ReferenceClassDescImpl::ofValidated(String)`, which also avoids
going through `Class::descriptorString()` for a statically known class
descriptor:
Suggestion:
private static final ClassDesc CD_BiPredicate =
ReferenceClassDescImpl.ofValidated("Ljava/util/function/BiPredicate;");
src/java.base/share/classes/java/lang/runtime/SwitchBootstraps.java line 97:
> 95: ConstantDescs.CD_int,
> 96: CD_BiPredicate,
> 97: ConstantDescs.CD_List);
These can use `MethodTypeDescImpl::ofValidated(…)`:
Suggestion:
private static final MethodTypeDesc MTD_TYPE_SWITCH =
MethodTypeDescImpl.ofValidated(ConstantDescs.CD_int,
ConstantDescs.CD_Object,
ConstantDescs.CD_int);
private static final MethodTypeDesc MTD_TYPE_SWITCH_EXTRA =
MethodTypeDescImpl.ofValidated(ConstantDescs.CD_int,
ConstantDescs.CD_Object,
ConstantDescs.CD_int,
CD_BiPredicate,
ConstantDescs.CD_List);
-------------
PR Review Comment: https://git.openjdk.org/jdk/pull/20693#discussion_r1729952813
PR Review Comment: https://git.openjdk.org/jdk/pull/20693#discussion_r1729952571
