summaryrefslogtreecommitdiff
path: root/arch/x86/lib/atomic64_386_32.S
blob: 5db07fe4a0caf4c9e0964c26c20e5af12060afe5 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
/*
 * atomic64_t for 386/486
 *
 * Copyright © 2010  Luca Barbieri
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 */

#include <linux/linkage.h>
#include <asm/alternative-asm.h>
#include <asm/dwarf2.h>

/* if you want SMP support, implement these with real spinlocks */
.macro LOCK reg
	pushfl
	CFI_ADJUST_CFA_OFFSET 4
	cli
.endm

.macro UNLOCK reg
	popfl
	CFI_ADJUST_CFA_OFFSET -4
.endm

.macro BEGIN func reg
$v = \reg

ENTRY(atomic64_\func\()_386)
	CFI_STARTPROC
	LOCK $v

.macro RETURN
	UNLOCK $v
	ret
.endm

.macro END_
	CFI_ENDPROC
ENDPROC(atomic64_\func\()_386)
.purgem RETURN
.purgem END_
.purgem END
.endm

.macro END
RETURN
END_
.endm
.endm

BEGIN read %ecx
	movl  ($v), %eax
	movl 4($v), %edx
END

BEGIN set %esi
	movl %ebx,  ($v)
	movl %ecx, 4($v)
END

BEGIN xchg %esi
	movl  ($v), %eax
	movl 4($v), %edx
	movl %ebx,  ($v)
	movl %ecx, 4($v)
END

BEGIN add %ecx
	addl %eax,  ($v)
	adcl %edx, 4($v)
END

BEGIN add_return %ecx
	addl  ($v), %eax
	adcl 4($v), %edx
	movl %eax,  ($v)
	movl %edx, 4($v)
END

BEGIN sub %ecx
	subl %eax,  ($v)
	sbbl %edx, 4($v)
END

BEGIN sub_return %ecx
	negl %edx
	negl %eax
	sbbl $0, %edx
	addl  ($v), %eax
	adcl 4($v), %edx
	movl %eax,  ($v)
	movl %edx, 4($v)
END

BEGIN inc %esi
	addl $1,  ($v)
	adcl $0, 4($v)
END

BEGIN inc_return %esi
	movl  ($v), %eax
	movl 4($v), %edx
	addl $1, %eax
	adcl $0, %edx
	movl %eax,  ($v)
	movl %edx, 4($v)
END

BEGIN dec %esi
	subl $1,  ($v)
	sbbl $0, 4($v)
END

BEGIN dec_return %esi
	movl  ($v), %eax
	movl 4($v), %edx
	subl $1, %eax
	sbbl $0, %edx
	movl %eax,  ($v)
	movl %edx, 4($v)
END

BEGIN add_unless %ecx
	addl %eax, %esi
	adcl %edx, %edi
	addl  ($v), %eax
	adcl 4($v), %edx
	cmpl %eax, %esi
	je 3f
1:
	movl %eax,  ($v)
	movl %edx, 4($v)
	xorl %eax, %eax
2:
RETURN
3:
	cmpl %edx, %edi
	jne 1b
	movl $1, %eax
	jmp 2b
END_

BEGIN inc_not_zero %esi
	movl  ($v), %eax
	movl 4($v), %edx
	testl %eax, %eax
	je 3f
1:
	addl $1, %eax
	adcl $0, %edx
	movl %eax,  ($v)
	movl %edx, 4($v)
	xorl %eax, %eax
2:
RETURN
3:
	testl %edx, %edx
	jne 1b
	movl $1, %eax
	jmp 2b
END_

BEGIN dec_if_positive %esi
	movl  ($v), %eax
	movl 4($v), %edx
	subl $1, %eax
	sbbl $0, %edx
	js 1f
	movl %eax,  ($v)
	movl %edx, 4($v)
1:
END