| … | |
… | |
| 44 | |
44 | |
| 45 | e = w.u; |
45 | e = w.u; |
| 46 | } |
46 | } |
| 47 | |
47 | |
| 48 | #if !HAVE_GCC_BUILTINS |
48 | #if !HAVE_GCC_BUILTINS |
| 49 | int ctz (unsigned int x) CONST |
49 | int rxvt_ctz (unsigned int x) CONST |
| 50 | { |
50 | { |
| 51 | int r = 0; |
51 | int r = 0; |
| 52 | |
52 | |
| 53 | x &= -x; // this isolates the lowest bit |
53 | x &= -x; // this isolates the lowest bit |
| 54 | |
54 | |
| … | |
… | |
| 59 | if (x & 0xffff0000) r += 16; |
59 | if (x & 0xffff0000) r += 16; |
| 60 | |
60 | |
| 61 | return r; |
61 | return r; |
| 62 | } |
62 | } |
| 63 | |
63 | |
| 64 | int popcount (unsigned int x) CONST |
64 | int rxvt_popcount (unsigned int x) CONST |
| 65 | { |
65 | { |
| 66 | x -= (x >> 1) & 0x55555555; |
66 | x -= (x >> 1) & 0x55555555; |
| 67 | x = ((x >> 2) & 0x33333333) + (x & 0x33333333); |
67 | x = ((x >> 2) & 0x33333333) + (x & 0x33333333); |
| 68 | x = ((x >> 4) + x) & 0x0f0f0f0f; |
68 | x = ((x >> 4) + x) & 0x0f0f0f0f; |
| 69 | x *= 0x01010101; |
69 | x *= 0x01010101; |
