Request for reviews (S): 6892186: 6896084: VM does not reserve protected page below heap for compressed oops implicit null checks
Vladimir.Kozlov at Sun.COM
Thu Oct 29 10:20:11 PDT 2009
I am taking this back. It will require adding
the cast in all expressions with this variable.
I will keep it as it was.
Vladimir Kozlov wrote:
> Thank you, Christian
> I will change the type to address.
> Christian Thalinger wrote:
>> On Wed, 2009-10-28 at 16:13 -0700, Vladimir Kozlov wrote:
>>> Fixed 6896084: VM does not reserve protected page below heap for
>>> compressed oops implicit null checks
>>> VM should reserve protected page below heap for compressed oops
>>> implicit null checks in compiled code (see 6716785).
>>> After zero based compressed oops changes (6791178) the page is
>>> not reserved because undefined narrow_oop_base (NULL by default)
>>> is used in ReservedHeapSpace() to determine if the page is needed.
>>> Set narrow_oop_base and narrow_oop_use_implicit_null_checks
>>> values according to compressed oops encoding mode in
>>> Universe::preferred_heap_base() which is called before
>>> ReservedHeapSpace() constructors.
>> Using size_t for base (which is an address) feels a little strange but
>> otherwise looks good.
>> -- Christian
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