review for 7121073: secondary_super_cache memory slice has incorrect bounds in flatten_alias_type

[Tom Rodriguez]

Thanks Vladimir.

tom

On Dec 15, 2011, at 12:57 PM, Vladimir Kozlov wrote:

> Good.
> 
> Thanks,
> Vladimir
> 
> Tom Rodriguez wrote:
>> On Dec 15, 2011, at 12:44 PM, Vladimir Kozlov wrote:
>>> Tom,
>>> 
>>> Can you updated related comments? Otherwise looks good.
>> How about this:
>>    // If we are referencing a field within a Klass, we need
>>    // to assume the worst case of an Object.  Both exact and
>>    // inexact types must flatten to the same alias class so
>>    // use NotNull as the PTR.
>> tom
>>> Thanks,
>>> Vladimir
>>> 
>>> Tom Rodriguez wrote:
>>>> http://cr.openjdk.java.net/~never/7121073
>>>> 7 lines changed: 2 ins; 0 del; 5 mod; 3239 unchg
>>>> 7121073: secondary_super_cache memory slice has incorrect bounds in flatten_alias_type
>>>> Reviewed-by:
>>>> To ensure that memory operations for type checks are properly ordered,
>>>> several fields are smeared together into the same alias slice.  The
>>>> existing logic is sloppy and includes a slightly larger chunk of
>>>> memory than intended.  Currently this is fine but changes to the shape
>>>> of Klass can invalidate it.  The fix is to properly test the
>>>> boundaries.  Additionally I changed the logic for setting the PTR to
>>>> use NotNull instead of Constant to be consisten with all the following
>>>> logic which uses NotNull.  Tested with full CTW.