RFR: 8265129: Add intrinsic support for JVM.getClassId [v2]

[Yi Yang]

On Fri, 23 Apr 2021 12:37:42 GMT, Denghui Dong <ddong at openjdk.org> wrote:

>> 8265129: Add intrinsic support for JVM.getClassId
>
> Denghui Dong has updated the pull request incrementally with one additional commit since the last revision:
> 
>   add doc

There are some comments rather than a real review that should be done by reviewers.

src/hotspot/share/c1/c1_LIRGenerator.cpp line 3049:

> 3047: 
> 3048: #ifdef JFR_HAVE_INTRINSICS
> 3049: void LIRGenerator::do_ClassIDIntrinsic(Intrinsic* x) {

Is this method really important and hot enough that we need to intrinsify it both in C1 and C2?

src/hotspot/share/c1/c1_LIRGenerator.cpp line 3095:

> 3093: 
> 3094:   LIR_Opr epoch = new_register(T_INT);
> 3095:   LIR_Opr epoch_address = new_register(T_LONG);

new_pointer_register

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PR: https://git.openjdk.java.net/jdk/pull/3470