RFR: 8279888: Local variable independently used by multiple loops can interfere with loop optimizations [v5]

[Roland Westrelin]

On Thu, 7 Apr 2022 19:53:27 GMT, Vladimir Kozlov <kvn at openjdk.org> wrote:

> Nice work. I have only comment about the flag.

Thanks for reviewing this @vnkozlov

> src/hotspot/share/opto/c2_globals.hpp line 768:
> 
>> 766:           range(0, max_juint)                                               \
>> 767:                                                                             \
>> 768:   product(bool, DuplicateBackedge, true,                                    \
> 
> Why flag is `product`?  Can it be `experimental` or `diagnostic`? I assume eventually we should remove this flag.

Right. I made it diagnostic in the new commit.

-------------

PR: https://git.openjdk.java.net/jdk/pull/7352