On Thu, 25 Jul 2024 13:56:34 GMT, Andrew Haley <a...@openjdk.org> wrote:
>> Thanks, now I see that `Class::isInstance(Object)` is backed by >> `Runtime1::is_instance_of()` which uses `oopDesc::is_a()` to do the job. >> >> If it turns out to be performance critical, the intrinsic implementation >> should be rewritten to exercise existing subtype checking support in C1. As >> it is implemented now, it's already quite inefficient. > > I did write an intrinsic for that, but it made this patch even larger. I have > a small patch for C1, for some other time. FYI I filed a low-priority RFE against C1 to track it ([JDK-8337251](https://bugs.openjdk.org/browse/JDK-8337251)). ------------- PR Review Comment: https://git.openjdk.org/jdk/pull/19989#discussion_r1692548251
