File: popcnt.go

package info (click to toggle)
golang-github-willf-bitset 1.1.3-3
  • links: PTS, VCS
  • area: main
  • in suites: buster
  • size: 180 kB
  • sloc: makefile: 127; asm: 95
file content (53 lines) | stat: -rw-r--r-- 1,020 bytes parent folder | download | duplicates (5)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
package bitset

// bit population count, take from
// https://code.google.com/p/go/issues/detail?id=4988#c11
// credit: https://code.google.com/u/arnehormann/
func popcount(x uint64) (n uint64) {
	x -= (x >> 1) & 0x5555555555555555
	x = (x>>2)&0x3333333333333333 + x&0x3333333333333333
	x += x >> 4
	x &= 0x0f0f0f0f0f0f0f0f
	x *= 0x0101010101010101
	return x >> 56
}

func popcntSliceGo(s []uint64) uint64 {
	cnt := uint64(0)
	for _, x := range s {
		cnt += popcount(x)
	}
	return cnt
}

func popcntMaskSliceGo(s, m []uint64) uint64 {
	cnt := uint64(0)
	for i := range s {
		cnt += popcount(s[i] &^ m[i])
	}
	return cnt
}

func popcntAndSliceGo(s, m []uint64) uint64 {
	cnt := uint64(0)
	for i := range s {
		cnt += popcount(s[i] & m[i])
	}
	return cnt
}

func popcntOrSliceGo(s, m []uint64) uint64 {
	cnt := uint64(0)
	for i := range s {
		cnt += popcount(s[i] | m[i])
	}
	return cnt
}

func popcntXorSliceGo(s, m []uint64) uint64 {
	cnt := uint64(0)
	for i := range s {
		cnt += popcount(s[i] ^ m[i])
	}
	return cnt
}