RFR(L): 8005071: Incremental inlining for JSR 292

[Roland Westrelin]

> I don't see the big need for new "dead code cleanup" code when we have already several implementations. We may need to adjust them to work for your case (PhaseIdealLoop work without inner loops).


I tried doing a PhaseIdealLoop for every inlining and compilation time (as reported by CITime) on nashorn benchmarks doubled for several of them. This said, it doesn't seem to affect the peak performance of the benchmarks except for one maybe. But we're also not very aggressive in the inlining we do currently.

I tried a CTW run with this change (with -XX:+AlwaysIncrementalInline: every inlining is done post parsing. That's how I've been stress testing things.) and there are several failures so it looks like if we decide to go that way, more time is required to get a clean run.

Roland.