RFR (S) 8182554: Code for os::random() assumes long is 32 bits

[coleen.phillimore at oracle.com]

Stefan had comments offline so here's another version to review that 
removes more (int) casts and reverts the return type of althashing 
object_hash(), and fixed the comment in synchronizer.cpp.

open webrev at http://cr.openjdk.java.net/~coleenp/8182554.02/webrev

Let me know if this looks good.
thanks,
Coleen


On 6/28/17 2:52 PM, coleen.phillimore at oracle.com wrote:
>
> I'm going to push with two Reviewers, mostly trivial change.
> thanks,
> Coleen
>
> On 6/28/17 2:48 PM, coleen.phillimore at oracle.com wrote:
>>
>>
>> On 6/28/17 2:01 PM, Kim Barrett wrote:
>>>> On Jun 28, 2017, at 11:46 AM, coleen.phillimore at oracle.com wrote:
>>>>
>>>> Summary: And make updating the _rand_seed thread safe.
>>>>
>>>> See bug for more details.
>>>>
>>>> open webrev at http://cr.openjdk.java.net/~coleenp/8182554.01/webrev
>>>> bug link https://bugs.openjdk.java.net/browse/JDK-8182554
>>>>
>>>> Tested with JPRT and performance tested addition of cas in 
>>>> os::random call (no regressions).   The only thing that uses 
>>>> os::random more than like once is Symbol creation.
>>>>
>>>> Thanks,
>>>> Coleen
>>> Something I missed during pre-review.  Sorry!
>>> - random_helper ought to be static (or added to os::).
>>
>> Ah yes, I forgot to do that with this version.  Thanks!
>>>
>>> Also, the seed in test_random is still (unsigned) long, and we're
>>> trying to eliminate potentially confusing uses of long.
>>
>> ahh, I missed one.
>>
>> Thanks!
>> Coleen
>>
>>>
>>> Looks good.  I don't need another webrev for those nits.
>>>
>>>
>>
>