xref: /linux/arch/x86/include/asm/arch_hweight.h (revision c39f2d9db0fd81ea20bb5cce9b3f082ca63753e2)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _ASM_X86_HWEIGHT_H
3 #define _ASM_X86_HWEIGHT_H
4 
5 #include <asm/cpufeatures.h>
6 
7 #ifdef CONFIG_64BIT
8 #define REG_IN "D"
9 #define REG_OUT "a"
10 #else
11 #define REG_IN "a"
12 #define REG_OUT "a"
13 #endif
14 
__arch_hweight32(unsigned int w)15 static __always_inline unsigned int __arch_hweight32(unsigned int w)
16 {
17 	unsigned int res;
18 
19 	asm (ALTERNATIVE("call __sw_hweight32", "popcntl %1, %0", X86_FEATURE_POPCNT)
20 			 : "="REG_OUT (res)
21 			 : REG_IN (w));
22 
23 	return res;
24 }
25 
__arch_hweight16(unsigned int w)26 static inline unsigned int __arch_hweight16(unsigned int w)
27 {
28 	return __arch_hweight32(w & 0xffff);
29 }
30 
__arch_hweight8(unsigned int w)31 static inline unsigned int __arch_hweight8(unsigned int w)
32 {
33 	return __arch_hweight32(w & 0xff);
34 }
35 
36 #ifdef CONFIG_X86_32
__arch_hweight64(__u64 w)37 static inline unsigned long __arch_hweight64(__u64 w)
38 {
39 	return  __arch_hweight32((u32)w) +
40 		__arch_hweight32((u32)(w >> 32));
41 }
42 #else
__arch_hweight64(__u64 w)43 static __always_inline unsigned long __arch_hweight64(__u64 w)
44 {
45 	unsigned long res;
46 
47 	asm (ALTERNATIVE("call __sw_hweight64", "popcntq %1, %0", X86_FEATURE_POPCNT)
48 			 : "="REG_OUT (res)
49 			 : REG_IN (w));
50 
51 	return res;
52 }
53 #endif /* CONFIG_X86_32 */
54 
55 #endif
56