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alexbowe/gist:907073

Created April 7, 2011 05:10
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15bit popcount from Hacker's Delight, p. 72
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gistfile1.cpp
//Special for 15-bit values on 64bit processors
//with fast multiplication
//From Hacker's Delight, p. 72
inline uint32_t popcount15(uint32_t x)
{
uint64_t y;
y = x * 0x0002000400080010;
y = y & 0x1111111111111111;
y = y * 0x1111111111111111;
y = y >> 60;
return y;
}
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