1 /*===---- lzcntintrin.h - LZCNT intrinsics ---------------------------------===
2 *
3 * Permission is hereby granted, free of charge, to any person obtaining a copy
4 * of this software and associated documentation files (the "Software"), to deal
5 * in the Software without restriction, including without limitation the rights
6 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
7 * copies of the Software, and to permit persons to whom the Software is
8 * furnished to do so, subject to the following conditions:
9 *
10 * The above copyright notice and this permission notice shall be included in
11 * all copies or substantial portions of the Software.
12 *
13 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
14 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
15 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
16 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
17 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
18 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
19 * THE SOFTWARE.
20 *
21 *===-----------------------------------------------------------------------===
22 */
23
24 #if !defined __X86INTRIN_H && !defined __IMMINTRIN_H
25 #error "Never use <lzcntintrin.h> directly; include <x86intrin.h> instead."
26 #endif
27
28 #ifndef __LZCNT__
29 # error "LZCNT instruction is not enabled"
30 #endif /* __LZCNT__ */
31
32 #ifndef __LZCNTINTRIN_H
33 #define __LZCNTINTRIN_H
34
35 static __inline__ unsigned short __attribute__((__always_inline__, __nodebug__))
__lzcnt16(unsigned short __X)36 __lzcnt16(unsigned short __X)
37 {
38 return __builtin_clzs(__X);
39 }
40
41 static __inline__ unsigned int __attribute__((__always_inline__, __nodebug__))
__lzcnt32(unsigned int __X)42 __lzcnt32(unsigned int __X)
43 {
44 return __builtin_clz(__X);
45 }
46
47 #ifdef __x86_64__
48 static __inline__ unsigned long long __attribute__((__always_inline__, __nodebug__))
__lzcnt64(unsigned long long __X)49 __lzcnt64(unsigned long long __X)
50 {
51 return __builtin_clzll(__X);
52 }
53 #endif
54
55 #endif /* __LZCNTINTRIN_H */
56