RFR: 8359965: Enable paired pushp and popp instruction usage for APX enabled CPUs [v2]

[Srinivas Vamsi Parasa]

On Thu, 3 Jul 2025 04:53:15 GMT, David Holmes <dholmes at openjdk.org> wrote:

>> Just a drive-by comment as this isn't code I normally have much to do with but to me it would look a lot cleaner to define `push_paired`/`pop_paired` (maybe abbreviating directly to `pushp`/`popp`?) rather than passing the boolean.
>
>> @dholmes-ora would you mind sharing your opinion? We seem to be making things more complicated, but hopefully in a good way?
> 
> Seems very complicated to me. Really this is for compiler folk to discuss. And as noted above this "tracker" class only helps where the push/pop are paired in the same scope. Personally I think a "pushp" that is defined to be a "push-paired" when available, else a regular "push", would suffice in terms of API design. But again this is for compiler folk to determine.

> Like @dholmes-ora, I also prefer a new function (in MacroAssembler) instead of flags. Though I like the names `paired_push`/`paired_pop`..
>

Please see the updated code with `paired_push`/`paired_pop`. Thanks for the suggestions!

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

PR Comment: https://git.openjdk.org/jdk/pull/25889#issuecomment-3050476284