RFR: 8367899: compiler/c2/gvn/TestBitCompressValueTransform.java intermittent timed out

[SendaoYan]

On Mon, 29 Sep 2025 13:52:59 GMT, SendaoYan <syan at openjdk.org> wrote:

> Hi all,
> 
> After JDK-8260555 change the timeout factor from 4 to 1, make test compiler/c2/gvn/TestBitCompressValueTransform.java intermittent timed out.
> 
> There are 20 10k/20k loop count of loops in this test, this cause test need many CPU cycles to finish. If I reduce the loop count from 10k/20k to 100/200, the test failures descripted in [JDK-8350896](https://bugs.openjdk.org/browse/JDK-8350896) also reproduced when the tested jdk is jdk25u. So it seems that there no need so many loop count for these tests.
> 
> Without the proposed change, the driver action finish about 65 sencods on linux-x64, with the proposed change the driver action finish about 1.5 seconds.

I have remove the loops which do not use the loop counter variable or do not use the random numer.

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PR Comment: https://git.openjdk.org/jdk/pull/27548#issuecomment-3350163073