On Sat, 29 Mar 2025 21:47:18 GMT, Kim Barrett <kbarr...@openjdk.org> wrote:
> Please review this change which adds a native method providing the > implementation of Reference::get. Referece::get is an intrinsic candidate, so > this native method implementation is only used when the intrinsic is not. > > Currently there is intrinsic support by the interpreter, C1, C2, and graal, > which are always used. With this change we can later remove all the > per-platform interpreter intrinsic implementations, and might also remove the > C1 intrinsic implementation. > > Testing: > (1) mach5 tier1-6 normal (so using all the existing intrinsics). > (2) mach5 tier1-6 with interpreter and C1 Reference::get intrinsics disabled. src/java.base/share/classes/java/lang/ref/Reference.java line 365: > 363: * C2 to sometimes prefer the native implementation over the > intrinsic. > 364: */ > 365: private native Object get0(); I think you can declare this as `private native T get0();` without changes to native method signatures, so you can avoid the unchecked cast above. (See Class::getPrimitiveClass declaration) Also, can C2 choose to use native over intrinsic? That is concerning from a performance POV, as I think there are a few such performance sensitive methods in core libraries. ------------- PR Review Comment: https://git.openjdk.org/jdk/pull/24315#discussion_r2022010819
