x86/mm/pat: Don't report PAT on CPUs that don't support it
[linux/fpc-iii.git] / arch / x86 / lib / hweight.S
blob23d893cbc2001094b0885ebf1811cf391192bbad
1 #include <linux/linkage.h>
2 #include <asm/export.h>
4 #include <asm/asm.h>
6 /*
7  * unsigned int __sw_hweight32(unsigned int w)
8  * %rdi: w
9  */
10 ENTRY(__sw_hweight32)
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
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
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)
36 EXPORT_SYMBOL(__sw_hweight32)
38 ENTRY(__sw_hweight64)
39 #ifdef CONFIG_X86_64
40         pushq   %rdi
41         pushq   %rdx
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
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
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
65         popq    %rdx
66         popq    %rdi
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
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
78         popl    %ecx
79         ret
80 #endif
81 ENDPROC(__sw_hweight64)
82 EXPORT_SYMBOL(__sw_hweight64)