[x265] x265 bug report

[nathan]

hi Guys,
At source/common/pixel.cpp: line 203
An function seems have an error:
// in: a pseudo-simd number of the form x+(y<<16)
// return: abs(x)+(abs(y)<<16)
inlinesum2_tabs2(sum2_ta)
{
    sum2_ts = ((a >> (BITS_PER_SUM - 1)) & (((sum2_t)1 << BITS_PER_SUM) + 1)) * ((sum_t)-1);


    return (a + s) ^ s;
}                    
see my test :
int main()
{
    sum_t    A = -1;   # 0xffff
    sum_t    B = -2;   # 0xfffe
    sum2_t  C = (B << BITS_PER_SUM) + A; # 0xfffeffff
    sum2_t  D = abs2(C);                                 # 0x00010001
    sum2_t  E = (2 << BITS_PER_SUM) + 1;  # 0x00020001
}
At the function description, the D should be equal to  E, but it not the same from my test.
(please check the test is ok or not, in case I missed something....)



the abs2() is used to calculate SATD,  which effect the selection of motion evaluation, not effect the correctness of encoder function.


(can someone tell me where can I commit this bug report to?  Thanks!)
BR-x265,
     Nathan
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