Bug 5091921: Sign flip issues in loop optimizer

[Vladimir Kozlov]

Dawid,

your problem (7024475), it seems, is not related to the sign flip problem.
It is a regression after 6384206 changes in 6u14, as Tom pointed.
The sign flip problem exists from day one of Hotspot VM.

Vladimir

Dawid Weiss wrote:
>> since, as easy to reproduce it, it is also easy to avoid it by modifying
>> java program.
> 
> Can you expand on this, please? While the issue in Lucene could be
> worked around by manually unrolling the loop, I don't see a trivial
> fix for the case I was hitting, where was a nesting of two loops with
> correlated counters.
> 
> Dawid