RFR: 8161265: [JVMCI] EnableJVMCI should only be required when its not implied by other flags
doug.simon at oracle.com
Wed Jul 13 09:20:46 UTC 2016
The -XX:+EnableJVMCI option 1) unlocks code paths in the VM related to JVMCI and 2) is required to unlock all other JVMCI options. However, 1 could be achieved by specific JVMCI options without requiring 2. Since JVMCI is experimental, these options already require -XX:+UnlockExperimentalVMOptions. Having to unlock them twice is redundant and makes for unnecessarily long command lines. For example:
java -XX:+UnlockExperimentalVMOptions -XX:+EnableJVMCI -XX:+UseJVMCICompiler ...
java -XX:+UnlockExperimentalVMOptions -XX:+UseJVMCICompiler ...
This webrev removes the need for specifying -XX:+EnableJVMCI for these options:
It also significantly simplifies the logic for checking consistency for JVMCI options. The trade off is that when new JVMCI options are added, the logic in JVMCIGlobals::check_jvmci_flags_are_consistent needs to be updated.
Lastly, I took this opportunity to remove the CodeInstallSafepointChecks option as it should always be true.
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