RFR: 8370519: C2: Hit MemLimit when running with +VerifyLoopOptimizations [v3]

[Roland Westrelin]

On Mon, 1 Dec 2025 16:33:20 GMT, Benoît Maillard <bmaillard at openjdk.org> wrote:

>> Roland Westrelin has updated the pull request incrementally with two additional commits since the last revision:
>> 
>>  - review
>>  - review
>
> test/hotspot/jtreg/compiler/c2/TestVerifyLoopOptimizationsHighMemUsage.java line 28:
> 
>> 26:  * @bug 8370519
>> 27:  * @summary C2: Hit MemLimit when running with +VerifyLoopOptimizations
>> 28:  * @run main/othervm -XX:CompileCommand=compileonly,*TestVerifyLoopOptimizationsHighMemUsage*::* -XX:-TieredCompilation -Xbatch
> 
> Out of curiosity, have you try reducing the test with `creduce`? I fixed a similar issue in [JDK-8366990](https://bugs.openjdk.org/browse/JDK-8366990), and initially reviewers were concerned about the long compilation time. I was able to get decent results with `creduce` by using  `-XX:CompileCommand=memlimit`. Not sure if it's worth doing here though.

I don't have `creduce` set up. I tried minimizing the test case by hand but it was fairly time consuming. It currently runs in 30s on a fairly fast machine.

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PR Review Comment: https://git.openjdk.org/jdk/pull/28581#discussion_r2580733874