RFR (XS): 8191915: JCK tests produce incorrect results with C2
tobias.hartmann at oracle.com
Thu Jan 11 13:06:37 UTC 2018
On 11.01.2018 10:30, Rickard Bäckman wrote:
Looks correct to me. Maybe add a comment explaining all the casting.
> 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.
>>> 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
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