Commit | Line | Data |
---|---|---|
f5967101 | 1 | #include <linux/linkage.h> |
784d5699 | 2 | #include <asm/export.h> |
f5967101 BP |
3 | |
4 | #include <asm/asm.h> | |
5 | ||
6 | /* | |
7 | * unsigned int __sw_hweight32(unsigned int w) | |
8 | * %rdi: w | |
9 | */ | |
10 | ENTRY(__sw_hweight32) | |
11 | ||
12 | #ifdef CONFIG_X86_64 | |
13 | movl %edi, %eax # w | |
14 | #endif | |
15 | __ASM_SIZE(push,) %__ASM_REG(dx) | |
16 | movl %eax, %edx # w -> t | |
17 | shrl %edx # t >>= 1 | |
18 | andl $0x55555555, %edx # t &= 0x55555555 | |
19 | subl %edx, %eax # w -= t | |
20 | ||
21 | movl %eax, %edx # w -> t | |
22 | shrl $2, %eax # w_tmp >>= 2 | |
23 | andl $0x33333333, %edx # t &= 0x33333333 | |
24 | andl $0x33333333, %eax # w_tmp &= 0x33333333 | |
25 | addl %edx, %eax # w = w_tmp + t | |
26 | ||
27 | movl %eax, %edx # w -> t | |
28 | shrl $4, %edx # t >>= 4 | |
29 | addl %edx, %eax # w_tmp += t | |
30 | andl $0x0f0f0f0f, %eax # w_tmp &= 0x0f0f0f0f | |
31 | imull $0x01010101, %eax, %eax # w_tmp *= 0x01010101 | |
32 | shrl $24, %eax # w = w_tmp >> 24 | |
33 | __ASM_SIZE(pop,) %__ASM_REG(dx) | |
34 | ret | |
35 | ENDPROC(__sw_hweight32) | |
784d5699 | 36 | EXPORT_SYMBOL(__sw_hweight32) |
f5967101 BP |
37 | |
38 | ENTRY(__sw_hweight64) | |
39 | #ifdef CONFIG_X86_64 | |
65ea11ec | 40 | pushq %rdi |
f5967101 BP |
41 | pushq %rdx |
42 | ||
43 | movq %rdi, %rdx # w -> t | |
44 | movabsq $0x5555555555555555, %rax | |
45 | shrq %rdx # t >>= 1 | |
46 | andq %rdx, %rax # t &= 0x5555555555555555 | |
47 | movabsq $0x3333333333333333, %rdx | |
48 | subq %rax, %rdi # w -= t | |
49 | ||
50 | movq %rdi, %rax # w -> t | |
51 | shrq $2, %rdi # w_tmp >>= 2 | |
52 | andq %rdx, %rax # t &= 0x3333333333333333 | |
53 | andq %rdi, %rdx # w_tmp &= 0x3333333333333333 | |
54 | addq %rdx, %rax # w = w_tmp + t | |
55 | ||
56 | movq %rax, %rdx # w -> t | |
57 | shrq $4, %rdx # t >>= 4 | |
58 | addq %rdx, %rax # w_tmp += t | |
59 | movabsq $0x0f0f0f0f0f0f0f0f, %rdx | |
60 | andq %rdx, %rax # w_tmp &= 0x0f0f0f0f0f0f0f0f | |
61 | movabsq $0x0101010101010101, %rdx | |
62 | imulq %rdx, %rax # w_tmp *= 0x0101010101010101 | |
63 | shrq $56, %rax # w = w_tmp >> 56 | |
64 | ||
65 | popq %rdx | |
65ea11ec | 66 | popq %rdi |
f5967101 BP |
67 | ret |
68 | #else /* CONFIG_X86_32 */ | |
69 | /* We're getting an u64 arg in (%eax,%edx): unsigned long hweight64(__u64 w) */ | |
70 | pushl %ecx | |
71 | ||
72 | call __sw_hweight32 | |
73 | movl %eax, %ecx # stash away result | |
74 | movl %edx, %eax # second part of input | |
75 | call __sw_hweight32 | |
76 | addl %ecx, %eax # result | |
77 | ||
78 | popl %ecx | |
79 | ret | |
80 | #endif | |
81 | ENDPROC(__sw_hweight64) | |
784d5699 | 82 | EXPORT_SYMBOL(__sw_hweight64) |