RFR (XS): 8191915: JCK tests produce incorrect results with C2

[Tobias Hartmann]

Hi Rickard,

On 11.01.2018 10:30, Rickard Bäckman wrote:
> http://cr.openjdk.java.net/~rbackman/8191915.2/

Looks correct to me. Maybe add a comment explaining all the casting.

Best regards,
Tobias


> On 01/10, Andrew Haley wrote:
>> On 10/01/18 14:17, Rickard Bäckman wrote:
>>> I did the multiply as unsigned and then cast to to signed thing.
>>> Renamed the test to LongMulOverflowTest.
>>>
>>> Updated.
>>>
>>> http://cr.openjdk.java.net/~rbackman/8191915.1/
>>>
>>> I agree that the best solution would be to use compiler builtins but I'm
>>> not sure all the compilers support them and makes portability a pain.
>>
>> It's still wrong because
>>
>>     jlong ax = (val1 < 0 ? -val1 : val1);
>>     jlong ay = (val2 < 0 ? -val2 : val2);
>>
>> is undefined when val1 or val2 is Long.MIN_VALUE.
>>
>> -- 
>> Andrew Haley
>> Java Platform Lead Engineer
>> Red Hat UK Ltd. <https://www.redhat.com>
>> EAC8 43EB D3EF DB98 CC77 2FAD A5CD 6035 332F A671
> /R
>