RFR: 8351661: NMT: VMATree should support separate call-stacks for reserve and commit operations [v2]

[Afshin Zafari]

On Thu, 13 Mar 2025 16:18:52 GMT, Gerard Ziemski <gziemski at openjdk.org> wrote:

>> Afshin Zafari has updated the pull request incrementally with one additional commit since the last revision:
>> 
>>   fixed a bug.
>
> src/hotspot/share/nmt/vmatree.cpp line 100:
> 
>> 98:         stB.in.set_stack(leqA_n->val().out.stack());
>> 99:         stA.out.set_second_stack(metadata.stack_idx);
>> 100:         stB.in.set_second_stack(metadata.stack_idx);
> 
> Did we consider naming them differently?
> 
> One obvious choice would be ReserveStack and CommitStack?
> 
> Right now, we need to mentally map them one way, and I am afraid that we could possibly get it reversed at some other point in code...

One StackIndex is used for all reserve/commit/uncommit/release operations.
We need another one just used for committing and uncommitting the start-node of the reserved region.
So names like ReserveXXX and CommitXXX would not fit. 
I do not insist on the chosen names and am open to proper alternatives.

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PR Review Comment: https://git.openjdk.org/jdk/pull/24028#discussion_r1994053947