RFR: 8344356: Aarch64: implement -XX:+VerifyActivationFrameSize [v2]

[Andrew Haley]

On Tue, 19 Nov 2024 10:06:30 GMT, SendaoYan <syan at openjdk.org> wrote:

>> Hi all,
>> Currently on aarch64 platform the debug VM option `-XX:+VerifyActivationFrameSize` is Unimplemented. I want to implement `-XX:+VerifyActivationFrameSize` to make JVM easier to diagnose. Only effect debug build plus with option `-XX:+VerifyActivationFrameSize`, the change has been verified locally, the risk is low.
>> 
>> Additional testing
>> 
>> - [ ] jtreg tests(include tier1/2/3 etc.) on linux-aarch64 release build
>> - [ ] jtreg tests(include tier1/2/3 etc.) on linux-aarch64 fastdebug build
>
> SendaoYan has updated the pull request incrementally with one additional commit since the last revision:
> 
>   use cmp instead cmpw

src/hotspot/cpu/aarch64/interp_masm_aarch64.cpp line 399:

> 397:     sub(rscratch2, rfp, esp);
> 398:     unsigned char min_frame_size = (frame::link_offset - frame::interpreter_frame_mirror_offset) * wordSize;
> 399:     cmp(rscratch2, min_frame_size);

Suggestion:

    int min_frame_size = (frame::link_offset - frame::interpreter_frame_mirror_offset) * wordSize;
    subs(rscratch2, min_frame_size);

The use of `subs` here is a bit odd, but it's less odd than defining `min_frame_size` as unsigned char.

-------------

PR Review Comment: https://git.openjdk.org/jdk/pull/22181#discussion_r1848105099