1 #ifndef _ASM_X86_HWEIGHT_H
2 #define _ASM_X86_HWEIGHT_H
3 
4 #include <asm/cpufeatures.h>
5 
6 #ifdef CONFIG_64BIT
7 /* popcnt %edi, %eax */
8 #define POPCNT32 ".byte 0xf3,0x0f,0xb8,0xc7"
9 /* popcnt %rdi, %rax */
10 #define POPCNT64 ".byte 0xf3,0x48,0x0f,0xb8,0xc7"
11 #define REG_IN "D"
12 #define REG_OUT "a"
13 #else
14 /* popcnt %eax, %eax */
15 #define POPCNT32 ".byte 0xf3,0x0f,0xb8,0xc0"
16 #define REG_IN "a"
17 #define REG_OUT "a"
18 #endif
19 
20 #define __HAVE_ARCH_SW_HWEIGHT
21 
22 static __always_inline unsigned int __arch_hweight32(unsigned int w)
23 {
24 	unsigned int res;
25 
26 	asm (ALTERNATIVE("call __sw_hweight32", POPCNT32, X86_FEATURE_POPCNT)
27 			 : "="REG_OUT (res)
28 			 : REG_IN (w));
29 
30 	return res;
31 }
32 
33 static inline unsigned int __arch_hweight16(unsigned int w)
34 {
35 	return __arch_hweight32(w & 0xffff);
36 }
37 
38 static inline unsigned int __arch_hweight8(unsigned int w)
39 {
40 	return __arch_hweight32(w & 0xff);
41 }
42 
43 #ifdef CONFIG_X86_32
44 static inline unsigned long __arch_hweight64(__u64 w)
45 {
46 	return  __arch_hweight32((u32)w) +
47 		__arch_hweight32((u32)(w >> 32));
48 }
49 #else
50 static __always_inline unsigned long __arch_hweight64(__u64 w)
51 {
52 	unsigned long res;
53 
54 	asm (ALTERNATIVE("call __sw_hweight64", POPCNT64, X86_FEATURE_POPCNT)
55 			 : "="REG_OUT (res)
56 			 : REG_IN (w));
57 
58 	return res;
59 }
60 #endif /* CONFIG_X86_32 */
61 
62 #endif
63