[jdk17u-dev] RFR: 8311588: C2: RepeatCompilation compiler directive does not choose stress seed randomly

[duke]

On Wed, 12 Nov 2025 00:04:24 GMT, Elif Aslan <duke at openjdk.org> wrote:

> Clean backport to make JDK-8319879 backporting cleaner. The compiler directive RepeatCompilation can be used to repeat compilations of specific methods, for example for Test::test():
> 
> -XX:CompileCommand=RepeatCompilation,Test::test,1000
> 
> When using this compiler directive in combination with StressIGVN/CCP/GCM/LCM, C2 only sets the stress seed once to a random value. Afterward, it keeps the seed for all repeated compilations. This should be changed to always select a random seed with each repetition (i.e. get the same behavior as the flag RepeatCompilation).

@elifaslan1 
Your change (at version 447542c97db551dc4457c84381ef5e680843a735) is now ready to be sponsored by a Committer.

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PR Comment: https://git.openjdk.org/jdk17u-dev/pull/4172#issuecomment-3522922027