Request for reviews (S): 6826736: CMS: core dump with -XX:+UseCompressedOops
Vladimir.Kozlov at Sun.COM
Wed Jul 22 13:42:39 PDT 2009
Thank you, John
I will fix comments.
John Coomes wrote:
> Vladimir Kozlov (Vladimir.Kozlov at Sun.COM) wrote:
>> Fixed 6826736: CMS: core dump with -XX:+UseCompressedOops
>> Compiled code may produce decoded oop = narrow_oop_base
>> when a narrow oop implicit null check is used.
>> Fix deoptimization code and GC to check for such oops values.
>> During deoptimization convert them to NULL.
>> And ignore them for GC (like NULL values are ignored).
> Looks reasonable to me, but I don't know this code. Spotted a couple
> of typos:
> 412 // is interesting in NULL.
> Change to interesting to interested.
> 432 assert((*loc) == (oop)NULL || Universe::narrow_oop_base() != (address)(void*)(*loc),
> 433 "found non valid value pointer");
> Change "non valid" to invalid.
> FWIW, I also like Paul's suggestion of is_narrow_oop_base(void*).
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