RFR(S): 8179618: Fixes for range of OptoLoopAlignment and Inlining flags

Lindenmaier, Goetz goetz.lindenmaier at sap.com
Thu May 4 10:57:24 UTC 2017


This change fixes range handling of a few flags of C2.
This should go to jdk10, and later be downported to some
update of jdk9.

Please review this change. I please need a sponsor.

Class WarmCallInfo limits its values to 1.0e10, but the flags used
to set it's fields (HotCallCountThreshold etc.) are limited by max_intx.
Using values over 1.0e10 causes assertions in the debug build.

OptoLoopAlignment must be a multiple of nop size, else it's not
possible to generate the instructions that go into the pad.
On x86 NOP size is 1, so it's no problem.
For SPARC, OptoLoopAlignmentConstraintFunc implements a special
case for bigger NOPs. This is also needed for s390 and ppc.
I just removed the #define, as the code works also on platforms
where NOPsize == 1. Actually, it should be optimized by the C
compiler in these cases.

Best regards,
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