RFR: 8342692: C2: long counted loop/long range checks: don't create loop-nest for short running loops [v20]

[Roland Westrelin]

On Thu, 15 May 2025 12:53:56 GMT, Christian Hagedorn <chagedorn at openjdk.org> wrote:

>> Roland Westrelin has updated the pull request incrementally with two additional commits since the last revision:
>> 
>>  - Emanuel's review
>>  - Christian's review
>
> src/hotspot/share/opto/loopnode.cpp line 1172:
> 
>> 1170:       // Only process if we are in the correct Predicate Block.
>> 1171:       return;
>> 1172:     }
> 
> Do we really need this check? Could we not just clone all Template Assertion Predicates that we find? I think with the recent Assertion Predicate changes, we are sure that all Template Assertion Predicates found belong to this loop. Otherwise, they would already be marked useless and `visit()` is not called on them.

Well, I trust you on that. Things have changed quite a bit recently with Assertion Predicates and it's hard to keep up!

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PR Review Comment: https://git.openjdk.org/jdk/pull/21630#discussion_r2091466589