RFR: 8376264: Mixed jstack could not unwind optimized frame [v2]

[Chris Plummer]

On Thu, 29 Jan 2026 03:43:23 GMT, Chris Plummer <cjplummer at openjdk.org> wrote:

>>> Remember states can be stacked, but your implementation only supports one push onto the state stack. I suppose you did this because you never saw a case where the stack was more than one deep.
>> 
>> Yes.
>> Remember states should be stacked, but I haven't seen that case. So I implemented to save (push) once so far.
>> I can fix it, but I want to do it in subsequent PR (for AArch64) because I will update register offset handling for generalization.
>
> Yes, a separate PR would be best.

Thinking about this a bit more, it's probably ok to continue to just support a 1 deep stack since that is all we'll likely every see. But if there is ever a second "push", an error should be produced, and if we ever see that error then we can then improve the stack handling.

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

PR Review Comment: https://git.openjdk.org/jdk/pull/29398#discussion_r2755673651