RFR: 8371464: C2: assert(no_dead_loop) failed: dead loop detected [v2]

[Damon Fenacci]

On Tue, 2 Dec 2025 09:04:52 GMT, Roland Westrelin <roland at openjdk.org> wrote:

>> src/hotspot/share/opto/cfgnode.cpp line 1404:
>> 
>>> 1402:       Node* other_phi_input = in(j);
>>> 1403:       if (other_phi_input != nullptr && other_phi_input == merge_mem->base_memory() && !is_data_loop(region, phi_input, igvn)) {
>>> 1404:         // merge_mem is a successor memory to other_phi_input, and is not pinned inside the diamond, so push it out.
>> 
>> Do you think it might be worth adding an additional reason for `!is_data_loop` in the comment?
>
> I added a comment in the new commit. Can you have a look?

👍 Thank you Roland.

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PR Review Comment: https://git.openjdk.org/jdk/pull/28554#discussion_r2580530978