[Bug tree-optimization/115857] New missed optimisation for hamming weight to simple popcnt

[fxue at os dot amperecomputing.com via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115857

Feng Xue <fxue at os dot amperecomputing.com> changed:

           What    |Removed                     |Added
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                 CC|                            |fxue at os dot 
amperecomputing.com

--- Comment #3 from Feng Xue <fxue at os dot amperecomputing.com> ---
Another case,

int hamming_weight(unsigned char value)
{
    int t = (int)value;

    t -= (t >> 1) & 0x55;
    t = (t & 0x33) + ((t >> 2) & 0x33);
    t = (t + (t >> 4)) & 0x0F;
    return t;
}