arch/x86/lib/atomic64_386_32.S

   1 /*
   2  * atomic64_t for 386/486
   3  *
   4  * Copyright © 2010  Luca Barbieri
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  */
  11
  12 #include <linux/linkage.h>
  13 #include <asm/alternative-asm.h>
  14 #include <asm/dwarf2.h>
  15
  16 /* if you want SMP support, implement these with real spinlocks */
  17 .macro LOCK reg
  18         pushfl_cfi
  19         cli
  20 .endm
  21
  22 .macro UNLOCK reg
  23         popfl_cfi
  24 .endm
  25
  26 #define BEGIN(op) \
  27 .macro endp; \
  28         CFI_ENDPROC; \
  29 ENDPROC(atomic64_##op##_386); \
  30 .purgem endp; \
  31 .endm; \
  32 ENTRY(atomic64_##op##_386); \
  33         CFI_STARTPROC; \
  34         LOCK v;
  35
  36 #define ENDP endp
  37
  38 #define RET \
  39         UNLOCK v; \
  40         ret
  41
  42 #define RET_ENDP \
  43         RET; \
  44         ENDP
  45
  46 #define v %ecx
  47 BEGIN(read)
  48         movl  (v), %eax
  49         movl 4(v), %edx
  50 RET_ENDP
  51 #undef v
  52
  53 #define v %esi
  54 BEGIN(set)
  55         movl %ebx,  (v)
  56         movl %ecx, 4(v)
  57 RET_ENDP
  58 #undef v
  59
  60 #define v  %esi
  61 BEGIN(xchg)
  62         movl  (v), %eax
  63         movl 4(v), %edx
  64         movl %ebx,  (v)
  65         movl %ecx, 4(v)
  66 RET_ENDP
  67 #undef v
  68
  69 #define v %ecx
  70 BEGIN(add)
  71         addl %eax,  (v)
  72         adcl %edx, 4(v)
  73 RET_ENDP
  74 #undef v
  75
  76 #define v %ecx
  77 BEGIN(add_return)
  78         addl  (v), %eax
  79         adcl 4(v), %edx
  80         movl %eax,  (v)
  81         movl %edx, 4(v)
  82 RET_ENDP
  83 #undef v
  84
  85 #define v %ecx
  86 BEGIN(sub)
  87         subl %eax,  (v)
  88         sbbl %edx, 4(v)
  89 RET_ENDP
  90 #undef v
  91
  92 #define v %ecx
  93 BEGIN(sub_return)
  94         negl %edx
  95         negl %eax
  96         sbbl $0, %edx
  97         addl  (v), %eax
  98         adcl 4(v), %edx
  99         movl %eax,  (v)
 100         movl %edx, 4(v)
 101 RET_ENDP
 102 #undef v
 103
 104 #define v %esi
 105 BEGIN(inc)
 106         addl $1,  (v)
 107         adcl $0, 4(v)
 108 RET_ENDP
 109 #undef v
 110
 111 #define v %esi
 112 BEGIN(inc_return)
 113         movl  (v), %eax
 114         movl 4(v), %edx
 115         addl $1, %eax
 116         adcl $0, %edx
 117         movl %eax,  (v)
 118         movl %edx, 4(v)
 119 RET_ENDP
 120 #undef v
 121
 122 #define v %esi
 123 BEGIN(dec)
 124         subl $1,  (v)
 125         sbbl $0, 4(v)
 126 RET_ENDP
 127 #undef v
 128
 129 #define v %esi
 130 BEGIN(dec_return)
 131         movl  (v), %eax
 132         movl 4(v), %edx
 133         subl $1, %eax
 134         sbbl $0, %edx
 135         movl %eax,  (v)
 136         movl %edx, 4(v)
 137 RET_ENDP
 138 #undef v
 139
 140 #define v %esi
 141 BEGIN(add_unless)
 142         addl %eax, %ecx
 143         adcl %edx, %edi
 144         addl  (v), %eax
 145         adcl 4(v), %edx
 146         cmpl %eax, %ecx
 147         je 3f
 148 1:
 149         movl %eax,  (v)
 150         movl %edx, 4(v)
 151         movl $1, %eax
 152 2:
 153         RET
 154 3:
 155         cmpl %edx, %edi
 156         jne 1b
 157         xorl %eax, %eax
 158         jmp 2b
 159 ENDP
 160 #undef v
 161
 162 #define v %esi
 163 BEGIN(inc_not_zero)
 164         movl  (v), %eax
 165         movl 4(v), %edx
 166         testl %eax, %eax
 167         je 3f
 168 1:
 169         addl $1, %eax
 170         adcl $0, %edx
 171         movl %eax,  (v)
 172         movl %edx, 4(v)
 173         movl $1, %eax
 174 2:
 175         RET
 176 3:
 177         testl %edx, %edx
 178         jne 1b
 179         jmp 2b
 180 ENDP
 181 #undef v
 182
 183 #define v %esi
 184 BEGIN(dec_if_positive)
 185         movl  (v), %eax
 186         movl 4(v), %edx
 187         subl $1, %eax
 188         sbbl $0, %edx
 189         js 1f
 190         movl %eax,  (v)
 191         movl %edx, 4(v)
 192 1:
 193 RET_ENDP
 194 #undef v