Unsafe for array access

David Chase david.r.chase at oracle.com
Wed May 7 17:23:58 UTC 2014

Don't we now have an Unsigned class providing these operations? (which could be intrinsified)
Or did we want to tie the intrinsic more closely to array classes?


On 2014-05-07, at 11:56 AM, John Rose <john.r.rose at oracle.com> wrote:

>> On May 7, 2014, at 4:30 AM, Doug Lea <dl at cs.oswego.edu> wrote:
>> Relatedly, it might be be nice to have an intrinsic boundsCheck(array, index)
>> that could be used in such cases that implemented using the more efficient
>> (using C): (unsigned)index >= (unsigned)array.length, plus relied on more
>> efficient VM throw mechanics on failure.
> We need an intrinsic like this for Arrays 2.0. Might as well do it now, since we have an immediate application. 
> Counterpoint:  optimizer can and should generate similar code for plain user written range tests. 
> Advice:  Do both, and the intrinsic will give everybody a clearer target to aim for. Unit test the intrinsic optimization, and several similar formulations. 
> – John

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