Bug 5091921: Sign flip issues in loop optimizer

Dawid Weiss dawid.weiss at gmail.com
Mon Mar 21 13:34:48 PDT 2011

Ah, clear now. Thanks Vladimir.


On Mon, Mar 21, 2011 at 6:03 PM, Vladimir Kozlov
<vladimir.kozlov at oracle.com> wrote:
> 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

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