You might want to give it a spin on Prime (Zing) 11 and see what you get, the Falcon JIT in Prime will do polymorphic guarded in-line caching for up to 6 implementers by default, I believe (as is configurable to higher if needed). This is exactly the sort of thing that capability is meant for.
On Saturday, February 5, 2022 at 1:35:31 AM UTC-10 [email protected] wrote: > JVM 11+ (OpenJDK / Zulu) > > sobota, 5 lutego 2022 o 12:30:38 UTC+1 [email protected] napisał(a): > >> which jvm? >> >> On Sat, Feb 5, 2022 at 6:26 AM r r <[email protected]> wrote: >> >>> Hello, >>> we know that there are some techniques that make virtual calls not so >>> expensive in JVM like Inline Cache or Polymorphic Inline Cache. >>> >>> Let's consider the following situation: >>> >>> Base is an interface. >>> >>> public void f(Base[] b) { >>> for(int i = 0; i < b.length; i++) { >>> b[i].m(); >>> } >>> } >>> >>> I see from my profiler that calling virtual (interface) method m is >>> relatively expensive. >>> f is on the hot path and it was compiled to machine code (C2) but I see >>> that call to m is a real virtual call. It means that it was not >>> optimised by JVM. >>> >>> The question is, how to deal with a such situation? Obviously, I cannot >>> make the method m not virtual here because it requires a serious >>> redesign. >>> >>> Can I do anything or I have to accept it? I was thinking how to "force" >>> or "convince" a JVM to >>> >>> 1. use polymorphic inline cache here - the number of different types in >>> b is quite low - between 4-5 types. >>> 2. to unroll this loop - length of b is also relatively small. After an >>> unroll it is possible that Inline Cache will be helpful here. >>> >>> Thanks in advance for any advices. >>> Regards, >>> >>> -- >>> You received this message because you are subscribed to the Google >>> Groups "mechanical-sympathy" group. >>> To unsubscribe from this group and stop receiving emails from it, send >>> an email to [email protected]. >>> To view this discussion on the web, visit >>> https://groups.google.com/d/msgid/mechanical-sympathy/9b52b34e-6388-4cba-b89e-ce7521109cban%40googlegroups.com >>> >>> <https://groups.google.com/d/msgid/mechanical-sympathy/9b52b34e-6388-4cba-b89e-ce7521109cban%40googlegroups.com?utm_medium=email&utm_source=footer> >>> . >>> >> >> >> -- >> Studying for the Turing test >> > -- You received this message because you are subscribed to the Google Groups "mechanical-sympathy" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web, visit https://groups.google.com/d/msgid/mechanical-sympathy/79ac85ac-73f6-4b7b-b775-85a02f838939n%40googlegroups.com.
