http://cr.openjdk.java.net/~vlivanov/8033666/webrev.01/
https://bugs.openjdk.java.net/browse/JDK-8033666
ValueConversions::castReference was introduced to workaround a problem
with unreliable inlining of Class::cast method. Unfortunately, since
ValueConversions class is located in sun.invoke.util,
@java.lang.invoke.ForceInline annotation isn't visible to it.
A proper fix would be to teach Hotspot to treat Class::cast specifically
and always inline it, but it requires extensive exploration of
performance implications. Filed 8035809 [1] to track that.
As an interim fix, I moved castReference method into
java.lang.invoke.MethodHandleImpl class and added new entry point
ValueConversions::cast which accepts a method handle to a method which
should be used for casting.
Testing: manual (looked through -XX:+PrintInlining output to ensure
MHI::castReference is inlined), jdk/java/lang/invoke, octane.
Thanks!
Best regards,
Vladimir Ivanov
[1] 8035809: Improve inlining of Class::cast method
https://bugs.openjdk.java.net/browse/JDK-8035809
