1 // Copyright 2015 The Go Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style
3 // license that can be found in the LICENSE file.
4
5 #include "textflag.h"
6 #include "funcdata.h"
7
8 // bool Cas(int32 *val, int32 old, int32 new)
9 // Atomically:
10 // if(*val == old){
11 // *val = new;
12 // return 1;
13 // }else
14 // return 0;
15 TEXT ·Cas(SB), NOSPLIT, $0-13
16 MOVL ptr+0(FP), BX
17 MOVL old+4(FP), AX
18 MOVL new+8(FP), CX
19 LOCK
20 CMPXCHGL CX, 0(BX)
21 SETEQ ret+12(FP)
22 RET
23
24 TEXT ·Casint32(SB), NOSPLIT, $0-13
25 JMP ·Cas(SB)
26
27 TEXT ·Casint64(SB), NOSPLIT, $0-21
28 JMP ·Cas64(SB)
29
30 TEXT ·Casuintptr(SB), NOSPLIT, $0-13
31 JMP ·Cas(SB)
32
33 TEXT ·CasRel(SB), NOSPLIT, $0-13
34 JMP ·Cas(SB)
35
36 TEXT ·Loaduintptr(SB), NOSPLIT, $0-8
37 JMP ·Load(SB)
38
39 TEXT ·Loaduint(SB), NOSPLIT, $0-8
40 JMP ·Load(SB)
41
42 TEXT ·Storeint32(SB), NOSPLIT, $0-8
43 JMP ·Store(SB)
44
45 TEXT ·Storeint64(SB), NOSPLIT, $0-12
46 JMP ·Store64(SB)
47
48 TEXT ·Storeuintptr(SB), NOSPLIT, $0-8
49 JMP ·Store(SB)
50
51 TEXT ·Xadduintptr(SB), NOSPLIT, $0-12
52 JMP ·Xadd(SB)
53
54 TEXT ·Loadint32(SB), NOSPLIT, $0-8
55 JMP ·Load(SB)
56
57 TEXT ·Loadint64(SB), NOSPLIT, $0-12
58 JMP ·Load64(SB)
59
60 TEXT ·Xaddint32(SB), NOSPLIT, $0-12
61 JMP ·Xadd(SB)
62
63 TEXT ·Xaddint64(SB), NOSPLIT, $0-20
64 JMP ·Xadd64(SB)
65
66 // bool ·Cas64(uint64 *val, uint64 old, uint64 new)
67 // Atomically:
68 // if(*val == old){
69 // *val = new;
70 // return 1;
71 // } else {
72 // return 0;
73 // }
74 TEXT ·Cas64(SB), NOSPLIT, $0-21
75 NO_LOCAL_POINTERS
76 MOVL ptr+0(FP), BP
77 TESTL $7, BP
78 JZ 2(PC)
79 CALL ·panicUnaligned(SB)
80 MOVL old_lo+4(FP), AX
81 MOVL old_hi+8(FP), DX
82 MOVL new_lo+12(FP), BX
83 MOVL new_hi+16(FP), CX
84 LOCK
85 CMPXCHG8B 0(BP)
86 SETEQ ret+20(FP)
87 RET
88
89 // bool Casp1(void **p, void *old, void *new)
90 // Atomically:
91 // if(*p == old){
92 // *p = new;
93 // return 1;
94 // }else
95 // return 0;
96 TEXT ·Casp1(SB), NOSPLIT, $0-13
97 MOVL ptr+0(FP), BX
98 MOVL old+4(FP), AX
99 MOVL new+8(FP), CX
100 LOCK
101 CMPXCHGL CX, 0(BX)
102 SETEQ ret+12(FP)
103 RET
104
105 // uint32 Xadd(uint32 volatile *val, int32 delta)
106 // Atomically:
107 // *val += delta;
108 // return *val;
109 TEXT ·Xadd(SB), NOSPLIT, $0-12
110 MOVL ptr+0(FP), BX
111 MOVL delta+4(FP), AX
112 MOVL AX, CX
113 LOCK
114 XADDL AX, 0(BX)
115 ADDL CX, AX
116 MOVL AX, ret+8(FP)
117 RET
118
119 TEXT ·Xadd64(SB), NOSPLIT, $0-20
120 NO_LOCAL_POINTERS
121 // no XADDQ so use CMPXCHG8B loop
122 MOVL ptr+0(FP), BP
123 TESTL $7, BP
124 JZ 2(PC)
125 CALL ·panicUnaligned(SB)
126 // DI:SI = delta
127 MOVL delta_lo+4(FP), SI
128 MOVL delta_hi+8(FP), DI
129 // DX:AX = *addr
130 MOVL 0(BP), AX
131 MOVL 4(BP), DX
132 addloop:
133 // CX:BX = DX:AX (*addr) + DI:SI (delta)
134 MOVL AX, BX
135 MOVL DX, CX
136 ADDL SI, BX
137 ADCL DI, CX
138
139 // if *addr == DX:AX {
140 // *addr = CX:BX
141 // } else {
142 // DX:AX = *addr
143 // }
144 // all in one instruction
145 LOCK
146 CMPXCHG8B 0(BP)
147
148 JNZ addloop
149
150 // success
151 // return CX:BX
152 MOVL BX, ret_lo+12(FP)
153 MOVL CX, ret_hi+16(FP)
154 RET
155
156 TEXT ·Xchg(SB), NOSPLIT, $0-12
157 MOVL ptr+0(FP), BX
158 MOVL new+4(FP), AX
159 XCHGL AX, 0(BX)
160 MOVL AX, ret+8(FP)
161 RET
162
163 TEXT ·Xchgint32(SB), NOSPLIT, $0-12
164 JMP ·Xchg(SB)
165
166 TEXT ·Xchgint64(SB), NOSPLIT, $0-20
167 JMP ·Xchg64(SB)
168
169 TEXT ·Xchguintptr(SB), NOSPLIT, $0-12
170 JMP ·Xchg(SB)
171
172 TEXT ·Xchg64(SB),NOSPLIT,$0-20
173 NO_LOCAL_POINTERS
174 // no XCHGQ so use CMPXCHG8B loop
175 MOVL ptr+0(FP), BP
176 TESTL $7, BP
177 JZ 2(PC)
178 CALL ·panicUnaligned(SB)
179 // CX:BX = new
180 MOVL new_lo+4(FP), BX
181 MOVL new_hi+8(FP), CX
182 // DX:AX = *addr
183 MOVL 0(BP), AX
184 MOVL 4(BP), DX
185 swaploop:
186 // if *addr == DX:AX
187 // *addr = CX:BX
188 // else
189 // DX:AX = *addr
190 // all in one instruction
191 LOCK
192 CMPXCHG8B 0(BP)
193 JNZ swaploop
194
195 // success
196 // return DX:AX
197 MOVL AX, ret_lo+12(FP)
198 MOVL DX, ret_hi+16(FP)
199 RET
200
201 TEXT ·StorepNoWB(SB), NOSPLIT, $0-8
202 MOVL ptr+0(FP), BX
203 MOVL val+4(FP), AX
204 XCHGL AX, 0(BX)
205 RET
206
207 TEXT ·Store(SB), NOSPLIT, $0-8
208 MOVL ptr+0(FP), BX
209 MOVL val+4(FP), AX
210 XCHGL AX, 0(BX)
211 RET
212
213 TEXT ·StoreRel(SB), NOSPLIT, $0-8
214 JMP ·Store(SB)
215
216 TEXT ·StoreReluintptr(SB), NOSPLIT, $0-8
217 JMP ·Store(SB)
218
219 // uint64 atomicload64(uint64 volatile* addr);
220 TEXT ·Load64(SB), NOSPLIT, $0-12
221 NO_LOCAL_POINTERS
222 MOVL ptr+0(FP), AX
223 TESTL $7, AX
224 JZ 2(PC)
225 CALL ·panicUnaligned(SB)
226 MOVQ (AX), M0
227 MOVQ M0, ret+4(FP)
228 EMMS
229 RET
230
231 // void ·Store64(uint64 volatile* addr, uint64 v);
232 TEXT ·Store64(SB), NOSPLIT, $0-12
233 NO_LOCAL_POINTERS
234 MOVL ptr+0(FP), AX
235 TESTL $7, AX
236 JZ 2(PC)
237 CALL ·panicUnaligned(SB)
238 // MOVQ and EMMS were introduced on the Pentium MMX.
239 MOVQ val+4(FP), M0
240 MOVQ M0, (AX)
241 EMMS
242 // This is essentially a no-op, but it provides required memory fencing.
243 // It can be replaced with MFENCE, but MFENCE was introduced only on the Pentium4 (SSE2).
244 XORL AX, AX
245 LOCK
246 XADDL AX, (SP)
247 RET
248
249 // void ·Or8(byte volatile*, byte);
250 TEXT ·Or8(SB), NOSPLIT, $0-5
251 MOVL ptr+0(FP), AX
252 MOVB val+4(FP), BX
253 LOCK
254 ORB BX, (AX)
255 RET
256
257 // void ·And8(byte volatile*, byte);
258 TEXT ·And8(SB), NOSPLIT, $0-5
259 MOVL ptr+0(FP), AX
260 MOVB val+4(FP), BX
261 LOCK
262 ANDB BX, (AX)
263 RET
264
265 TEXT ·Store8(SB), NOSPLIT, $0-5
266 MOVL ptr+0(FP), BX
267 MOVB val+4(FP), AX
268 XCHGB AX, 0(BX)
269 RET
270
271 // func Or(addr *uint32, v uint32)
272 TEXT ·Or(SB), NOSPLIT, $0-8
273 MOVL ptr+0(FP), AX
274 MOVL val+4(FP), BX
275 LOCK
276 ORL BX, (AX)
277 RET
278
279 // func And(addr *uint32, v uint32)
280 TEXT ·And(SB), NOSPLIT, $0-8
281 MOVL ptr+0(FP), AX
282 MOVL val+4(FP), BX
283 LOCK
284 ANDL BX, (AX)
285 RET
286
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