projects / ust.git / blame
| Commit | Line | Data |
|---|---|---|
| a09dac63 PMF |
1 | /* Copyright (C) 2009 Pierre-Marc Fournier |
| 2 | * | |
| 3 | * This library is free software; you can redistribute it and/or | |
| 4 | * modify it under the terms of the GNU Lesser General Public | |
| 5 | * License as published by the Free Software Foundation; either | |
| 6 | * version 2.1 of the License, or (at your option) any later version. | |
| 7 | * | |
| 8 | * This library is distributed in the hope that it will be useful, | |
| 9 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
| 10 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
| 11 | * Lesser General Public License for more details. | |
| 12 | * | |
| 13 | * You should have received a copy of the GNU Lesser General Public | |
| 14 | * License along with this library; if not, write to the Free Software | |
| 15 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA | |
| 16 | */ | |
| 17 | ||
| 5af57e62 PMF |
18 | #ifndef UST_PROCESSOR_H |
| 19 | #define UST_PROCESSOR_H | |
| d98a01c6 | 20 | |
| 0222e121 | 21 | #define ____cacheline_aligned __attribute__((aligned(CAA_CACHE_LINE_SIZE))) |
| 066b83b8 | 22 | |
| 6fa0d97f | 23 | #ifdef __i386 |
| d98a01c6 | 24 | |
| 6fa0d97f PMF |
25 | static inline int fls(int x) |
| 26 | { | |
| 27 | int r; | |
| 28 | asm("bsrl %1,%0\n\t" | |
| 29 | "cmovzl %2,%0" | |
| 30 | : "=&r" (r) : "rm" (x), "rm" (-1)); | |
| 31 | return r + 1; | |
| 32 | } | |
| 33 | ||
| 7f0357f0 | 34 | #elif defined(__x86_64) |
| d98a01c6 | 35 | |
| 6fa0d97f PMF |
36 | static inline int fls(int x) |
| 37 | { | |
| 38 | int r; | |
| 39 | asm("bsrl %1,%0\n\t" | |
| 40 | "cmovzl %2,%0" | |
| 41 | : "=&r" (r) : "rm" (x), "rm" (-1)); | |
| 42 | return r + 1; | |
| 43 | } | |
| 44 | ||
| 7f0357f0 | 45 | #elif defined(__PPC__) |
| 6fa0d97f | 46 | |
| 6fa0d97f PMF |
47 | static __inline__ int fls(unsigned int x) |
| 48 | { | |
| 49 | int lz; | |
| 50 | ||
| 51 | asm ("cntlzw %0,%1" : "=r" (lz) : "r" (x)); | |
| 52 | return 32 - lz; | |
| 53 | } | |
| 54 | ||
| 7f0357f0 MD |
55 | #else /* arch-agnostic */ |
| 56 | ||
| 57 | static __inline__ int fls(unsigned int x) | |
| 58 | { | |
| 59 | int r = 32; | |
| 60 | ||
| 61 | if (!x) | |
| 62 | return 0; | |
| 63 | if (!(x & 0xFFFF0000U)) { | |
| 64 | x <<= 16; | |
| 65 | r -= 16; | |
| 66 | } | |
| 67 | if (!(x & 0xFF000000U)) { | |
| 68 | x <<= 8; | |
| 69 | r -= 8; | |
| 70 | } | |
| 71 | if (!(x & 0xF0000000U)) { | |
| 72 | x <<= 4; | |
| 73 | r -= 4; | |
| 74 | } | |
| 75 | if (!(x & 0xC0000000U)) { | |
| 76 | x <<= 2; | |
| 77 | r -= 2; | |
| 78 | } | |
| 79 | if (!(x & 0x80000000U)) { | |
| 80 | x <<= 1; | |
| 81 | r -= 1; | |
| 82 | } | |
| 83 | return r; | |
| 84 | } | |
| 85 | ||
| 86 | #endif | |
| d98a01c6 | 87 | |
| 5af57e62 | 88 | #endif /* UST_PROCESSOR_H */ |