Request for reviews (S): 6877254: Server vm crashes with "no branches off of store slice" when run with CMS and UseSuperWord (default)
Thomas.Rodriguez at Sun.COM
Tue Sep 8 21:34:17 PDT 2009
On Sep 8, 2009, at 6:30 PM, Vladimir Kozlov wrote:
> I have concerns about StoreCMNode::Ideal(aidx) implementation.
> The result of memory_at() is never the same mergemem node.
> I either mergemem->base_memory() or mergemem->in(aidx)
> so your check will be always true.
You're right but i think that just means we can drop that test.
> Also mergemem nodes could be chained when the result of memory_at()
> is also mergemem.
I figured Ideal would be called again if there was more work to do and
it should be a rare case anyway. The mem of a StoreCM should only be
something besides a Store if the StoreCM is dead or if something weird
has gone on with cloning. These changes are pretty conservative since
we don't have a clear set of rules for when a StoreCM is dead though I
think we could if we wanted to.
> You can look on methods in memnode.cpp which search through
> mergemem for stores: step_through_mergemem(), find_previous_store().
> Changpeng Fang wrote:
>> Need additional reviews (Tom (never) proposed the implementation,
>> so I assume he is oked )!
>> Comments are in the webrev.
>> On 09/01/09 11:07, Changpeng Fang wrote:
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