diff options
| -rw-r--r-- | lobject.c | 31 |
1 files changed, 11 insertions, 20 deletions
| @@ -1,5 +1,5 @@ | |||
| 1 | /* | 1 | /* |
| 2 | ** $Id: lobject.c,v 1.96 2003/02/18 16:02:56 roberto Exp roberto $ | 2 | ** $Id: lobject.c,v 1.97 2003/04/03 13:35:34 roberto Exp roberto $ |
| 3 | ** Some generic functions over Lua objects | 3 | ** Some generic functions over Lua objects |
| 4 | ** See Copyright Notice in lua.h | 4 | ** See Copyright Notice in lua.h |
| 5 | */ | 5 | */ |
| @@ -45,29 +45,20 @@ int luaO_int2fb (unsigned int x) { | |||
| 45 | 45 | ||
| 46 | 46 | ||
| 47 | int luaO_log2 (unsigned int x) { | 47 | int luaO_log2 (unsigned int x) { |
| 48 | static const lu_byte log_8[255] = { | 48 | static const lu_byte log_2[256] = { |
| 49 | 0, | 49 | 0,1,2,2,3,3,3,3,4,4,4,4,4,4,4,4,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5, |
| 50 | 1,1, | ||
| 51 | 2,2,2,2, | ||
| 52 | 3,3,3,3,3,3,3,3, | ||
| 53 | 4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4, | ||
| 54 | 5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5, | ||
| 55 | 6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6, | 50 | 6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6, |
| 56 | 6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6, | ||
| 57 | 7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7, | ||
| 58 | 7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7, | 51 | 7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7, |
| 59 | 7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7, | 52 | 7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7, |
| 60 | 7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7 | 53 | 8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8, |
| 54 | 8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8, | ||
| 55 | 8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8, | ||
| 56 | 8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8 | ||
| 61 | }; | 57 | }; |
| 62 | if (x >= 0x00010000) { | 58 | int l = -1; |
| 63 | if (x >= 0x01000000) return log_8[((x>>24) & 0xff) - 1]+24; | 59 | while (x >= 256) { l += 8; x >>= 8; } |
| 64 | else return log_8[((x>>16) & 0xff) - 1]+16; | 60 | return l + log_2[x]; |
| 65 | } | 61 | |
| 66 | else { | ||
| 67 | if (x >= 0x00000100) return log_8[((x>>8) & 0xff) - 1]+8; | ||
| 68 | else if (x) return log_8[(x & 0xff) - 1]; | ||
| 69 | return -1; /* special `log' for 0 */ | ||
| 70 | } | ||
| 71 | } | 62 | } |
| 72 | 63 | ||
| 73 | 64 | ||
