1// Copyright 2022 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//
6// System calls and other sys.stuff for loong64, Linux
7//
8
9#include "go_asm.h"
10#include "go_tls.h"
11#include "textflag.h"
12#include "cgo/abi_loong64.h"
13
14#define AT_FDCWD	-100
15#define CLOCK_REALTIME	0
16#define CLOCK_MONOTONIC	1
17
18#define SYS_exit		93
19#define SYS_read		63
20#define SYS_write		64
21#define SYS_close		57
22#define SYS_getpid		172
23#define SYS_kill		129
24#define SYS_mmap		222
25#define SYS_munmap		215
26#define SYS_setitimer		103
27#define SYS_clone		220
28#define SYS_nanosleep		101
29#define SYS_sched_yield		124
30#define SYS_rt_sigreturn	139
31#define SYS_rt_sigaction	134
32#define SYS_rt_sigprocmask	135
33#define SYS_sigaltstack		132
34#define SYS_madvise		233
35#define SYS_mincore		232
36#define SYS_gettid		178
37#define SYS_futex		98
38#define SYS_sched_getaffinity	123
39#define SYS_exit_group		94
40#define SYS_tgkill		131
41#define SYS_openat		56
42#define SYS_clock_gettime	113
43#define SYS_brk			214
44#define SYS_pipe2		59
45#define SYS_timer_create	107
46#define SYS_timer_settime	110
47#define SYS_timer_delete	111
48
49// func exit(code int32)
50TEXT runtime·exit(SB),NOSPLIT|NOFRAME,$0-4
51	MOVW	code+0(FP), R4
52	MOVV	$SYS_exit_group, R11
53	SYSCALL
54	RET
55
56// func exitThread(wait *atomic.Uint32)
57TEXT runtime·exitThread(SB),NOSPLIT|NOFRAME,$0-8
58	MOVV	wait+0(FP), R19
59	// We're done using the stack.
60	MOVW	$0, R11
61	DBAR
62	MOVW	R11, (R19)
63	DBAR
64	MOVW	$0, R4	// exit code
65	MOVV	$SYS_exit, R11
66	SYSCALL
67	JMP	0(PC)
68
69// func open(name *byte, mode, perm int32) int32
70TEXT runtime·open(SB),NOSPLIT|NOFRAME,$0-20
71	MOVW	$AT_FDCWD, R4 // AT_FDCWD, so this acts like open
72	MOVV	name+0(FP), R5
73	MOVW	mode+8(FP), R6
74	MOVW	perm+12(FP), R7
75	MOVV	$SYS_openat, R11
76	SYSCALL
77	MOVW	$-4096, R5
78	BGEU	R5, R4, 2(PC)
79	MOVW	$-1, R4
80	MOVW	R4, ret+16(FP)
81	RET
82
83// func closefd(fd int32) int32
84TEXT runtime·closefd(SB),NOSPLIT|NOFRAME,$0-12
85	MOVW	fd+0(FP), R4
86	MOVV	$SYS_close, R11
87	SYSCALL
88	MOVW	$-4096, R5
89	BGEU	R5, R4, 2(PC)
90	MOVW	$-1, R4
91	MOVW	R4, ret+8(FP)
92	RET
93
94// func write1(fd uintptr, p unsafe.Pointer, n int32) int32
95TEXT runtime·write1(SB),NOSPLIT|NOFRAME,$0-28
96	MOVV	fd+0(FP), R4
97	MOVV	p+8(FP), R5
98	MOVW	n+16(FP), R6
99	MOVV	$SYS_write, R11
100	SYSCALL
101	MOVW	R4, ret+24(FP)
102	RET
103
104// func read(fd int32, p unsafe.Pointer, n int32) int32
105TEXT runtime·read(SB),NOSPLIT|NOFRAME,$0-28
106	MOVW	fd+0(FP), R4
107	MOVV	p+8(FP), R5
108	MOVW	n+16(FP), R6
109	MOVV	$SYS_read, R11
110	SYSCALL
111	MOVW	R4, ret+24(FP)
112	RET
113
114// func pipe2(flags int32) (r, w int32, errno int32)
115TEXT runtime·pipe2(SB),NOSPLIT|NOFRAME,$0-20
116	MOVV	$r+8(FP), R4
117	MOVW	flags+0(FP), R5
118	MOVV	$SYS_pipe2, R11
119	SYSCALL
120	MOVW	R4, errno+16(FP)
121	RET
122
123// func usleep(usec uint32)
124TEXT runtime·usleep(SB),NOSPLIT,$16-4
125	MOVWU	usec+0(FP), R7
126	MOVV	$1000, R6
127	MULVU	R6, R7, R7
128	MOVV	$1000000000, R6
129
130	DIVVU	R6, R7, R5	// ts->tv_sec
131	REMVU	R6, R7, R4	// ts->tv_nsec
132	MOVV	R5, 8(R3)
133	MOVV	R4, 16(R3)
134
135	// nanosleep(&ts, 0)
136	ADDV	$8, R3, R4
137	MOVV	R0, R5
138	MOVV	$SYS_nanosleep, R11
139	SYSCALL
140	RET
141
142// func gettid() uint32
143TEXT runtime·gettid(SB),NOSPLIT,$0-4
144	MOVV	$SYS_gettid, R11
145	SYSCALL
146	MOVW	R4, ret+0(FP)
147	RET
148
149// func raise(sig uint32)
150TEXT runtime·raise(SB),NOSPLIT|NOFRAME,$0
151	MOVV	$SYS_getpid, R11
152	SYSCALL
153	MOVW	R4, R23
154	MOVV	$SYS_gettid, R11
155	SYSCALL
156	MOVW	R4, R5	// arg 2 tid
157	MOVW	R23, R4	// arg 1 pid
158	MOVW	sig+0(FP), R6	// arg 3
159	MOVV	$SYS_tgkill, R11
160	SYSCALL
161	RET
162
163// func raiseproc(sig uint32)
164TEXT runtime·raiseproc(SB),NOSPLIT|NOFRAME,$0
165	MOVV	$SYS_getpid, R11
166	SYSCALL
167	//MOVW	R4, R4	// arg 1 pid
168	MOVW	sig+0(FP), R5	// arg 2
169	MOVV	$SYS_kill, R11
170	SYSCALL
171	RET
172
173// func getpid() int
174TEXT ·getpid(SB),NOSPLIT|NOFRAME,$0-8
175	MOVV	$SYS_getpid, R11
176	SYSCALL
177	MOVV	R4, ret+0(FP)
178	RET
179
180// func tgkill(tgid, tid, sig int)
181TEXT ·tgkill(SB),NOSPLIT|NOFRAME,$0-24
182	MOVV	tgid+0(FP), R4
183	MOVV	tid+8(FP), R5
184	MOVV	sig+16(FP), R6
185	MOVV	$SYS_tgkill, R11
186	SYSCALL
187	RET
188
189// func setitimer(mode int32, new, old *itimerval)
190TEXT runtime·setitimer(SB),NOSPLIT|NOFRAME,$0-24
191	MOVW	mode+0(FP), R4
192	MOVV	new+8(FP), R5
193	MOVV	old+16(FP), R6
194	MOVV	$SYS_setitimer, R11
195	SYSCALL
196	RET
197
198// func timer_create(clockid int32, sevp *sigevent, timerid *int32) int32
199TEXT runtime·timer_create(SB),NOSPLIT,$0-28
200	MOVW	clockid+0(FP), R4
201	MOVV	sevp+8(FP), R5
202	MOVV	timerid+16(FP), R6
203	MOVV	$SYS_timer_create, R11
204	SYSCALL
205	MOVW	R4, ret+24(FP)
206	RET
207
208// func timer_settime(timerid int32, flags int32, new, old *itimerspec) int32
209TEXT runtime·timer_settime(SB),NOSPLIT,$0-28
210	MOVW	timerid+0(FP), R4
211	MOVW	flags+4(FP), R5
212	MOVV	new+8(FP), R6
213	MOVV	old+16(FP), R7
214	MOVV	$SYS_timer_settime, R11
215	SYSCALL
216	MOVW	R4, ret+24(FP)
217	RET
218
219// func timer_delete(timerid int32) int32
220TEXT runtime·timer_delete(SB),NOSPLIT,$0-12
221	MOVW	timerid+0(FP), R4
222	MOVV	$SYS_timer_delete, R11
223	SYSCALL
224	MOVW	R4, ret+8(FP)
225	RET
226
227// func mincore(addr unsafe.Pointer, n uintptr, dst *byte) int32
228TEXT runtime·mincore(SB),NOSPLIT|NOFRAME,$0-28
229	MOVV	addr+0(FP), R4
230	MOVV	n+8(FP), R5
231	MOVV	dst+16(FP), R6
232	MOVV	$SYS_mincore, R11
233	SYSCALL
234	MOVW	R4, ret+24(FP)
235	RET
236
237// func walltime() (sec int64, nsec int32)
238TEXT runtime·walltime(SB),NOSPLIT,$24-12
239	MOVV	R3, R23	// R23 is unchanged by C code
240	MOVV	R3, R25
241
242	MOVV	g_m(g), R24	// R24 = m
243
244	// Set vdsoPC and vdsoSP for SIGPROF traceback.
245	// Save the old values on stack and restore them on exit,
246	// so this function is reentrant.
247	MOVV	m_vdsoPC(R24), R11
248	MOVV	m_vdsoSP(R24), R7
249	MOVV	R11, 8(R3)
250	MOVV	R7, 16(R3)
251
252	MOVV    $ret-8(FP), R11 // caller's SP
253	MOVV	R1, m_vdsoPC(R24)
254	MOVV	R11, m_vdsoSP(R24)
255
256	MOVV	m_curg(R24), R4
257	MOVV	g, R5
258	BNE	R4, R5, noswitch
259
260	MOVV	m_g0(R24), R4
261	MOVV	(g_sched+gobuf_sp)(R4), R25	// Set SP to g0 stack
262
263noswitch:
264	SUBV	$16, R25
265	AND	$~15, R25	// Align for C code
266	MOVV	R25, R3
267
268	MOVW	$CLOCK_REALTIME, R4
269	MOVV	$0(R3), R5
270
271	MOVV	runtime·vdsoClockgettimeSym(SB), R20
272	BEQ	R20, fallback
273
274	// Store g on gsignal's stack, see sys_linux_arm64.s for detail
275	MOVBU	runtime·iscgo(SB), R25
276	BNE	R25, nosaveg
277
278	MOVV	m_gsignal(R24), R25	// g.m.gsignal
279	BEQ	R25, nosaveg
280	BEQ	g, R25, nosaveg
281
282	MOVV	(g_stack+stack_lo)(R25), R25	// g.m.gsignal.stack.lo
283	MOVV	g, (R25)
284
285	JAL	(R20)
286
287	MOVV	R0, (R25)
288	JMP	finish
289
290nosaveg:
291	JAL	(R20)
292
293finish:
294	MOVV	0(R3), R7	// sec
295	MOVV	8(R3), R5	// nsec
296
297	MOVV	R23, R3	// restore SP
298	// Restore vdsoPC, vdsoSP
299	// We don't worry about being signaled between the two stores.
300	// If we are not in a signal handler, we'll restore vdsoSP to 0,
301	// and no one will care about vdsoPC. If we are in a signal handler,
302	// we cannot receive another signal.
303	MOVV	16(R3), R25
304	MOVV	R25, m_vdsoSP(R24)
305	MOVV	8(R3), R25
306	MOVV	R25, m_vdsoPC(R24)
307
308	MOVV	R7, sec+0(FP)
309	MOVW	R5, nsec+8(FP)
310	RET
311
312fallback:
313	MOVV	$SYS_clock_gettime, R11
314	SYSCALL
315	JMP finish
316
317// func nanotime1() int64
318TEXT runtime·nanotime1(SB),NOSPLIT,$16-8
319	MOVV	R3, R23	// R23 is unchanged by C code
320	MOVV	R3, R25
321
322	MOVV	g_m(g), R24	// R24 = m
323
324	// Set vdsoPC and vdsoSP for SIGPROF traceback.
325	// Save the old values on stack and restore them on exit,
326	// so this function is reentrant.
327	MOVV	m_vdsoPC(R24), R11
328	MOVV	m_vdsoSP(R24), R7
329	MOVV	R11, 8(R3)
330	MOVV	R7, 16(R3)
331
332	MOVV    $ret-8(FP), R11 // caller's SP
333	MOVV	R1, m_vdsoPC(R24)
334	MOVV	R11, m_vdsoSP(R24)
335
336	MOVV	m_curg(R24), R4
337	MOVV	g, R5
338	BNE	R4, R5, noswitch
339
340	MOVV	m_g0(R24), R4
341	MOVV	(g_sched+gobuf_sp)(R4), R25	// Set SP to g0 stack
342
343noswitch:
344	SUBV	$16, R25
345	AND	$~15, R25	// Align for C code
346	MOVV	R25, R3
347
348	MOVW	$CLOCK_MONOTONIC, R4
349	MOVV	$0(R3), R5
350
351	MOVV	runtime·vdsoClockgettimeSym(SB), R20
352	BEQ	R20, fallback
353
354	// Store g on gsignal's stack, see sys_linux_arm64.s for detail
355	MOVBU	runtime·iscgo(SB), R25
356	BNE	R25, nosaveg
357
358	MOVV	m_gsignal(R24), R25	// g.m.gsignal
359	BEQ	R25, nosaveg
360	BEQ	g, R25, nosaveg
361
362	MOVV	(g_stack+stack_lo)(R25), R25	// g.m.gsignal.stack.lo
363	MOVV	g, (R25)
364
365	JAL	(R20)
366
367	MOVV	R0, (R25)
368	JMP	finish
369
370nosaveg:
371	JAL	(R20)
372
373finish:
374	MOVV	0(R3), R7	// sec
375	MOVV	8(R3), R5	// nsec
376
377	MOVV	R23, R3	// restore SP
378	// Restore vdsoPC, vdsoSP
379	// We don't worry about being signaled between the two stores.
380	// If we are not in a signal handler, we'll restore vdsoSP to 0,
381	// and no one will care about vdsoPC. If we are in a signal handler,
382	// we cannot receive another signal.
383	MOVV	16(R3), R25
384	MOVV	R25, m_vdsoSP(R24)
385	MOVV	8(R3), R25
386	MOVV	R25, m_vdsoPC(R24)
387
388	// sec is in R7, nsec in R5
389	// return nsec in R7
390	MOVV	$1000000000, R4
391	MULVU	R4, R7, R7
392	ADDVU	R5, R7
393	MOVV	R7, ret+0(FP)
394	RET
395
396fallback:
397	MOVV	$SYS_clock_gettime, R11
398	SYSCALL
399	JMP	finish
400
401// func rtsigprocmask(how int32, new, old *sigset, size int32)
402TEXT runtime·rtsigprocmask(SB),NOSPLIT|NOFRAME,$0-28
403	MOVW	how+0(FP), R4
404	MOVV	new+8(FP), R5
405	MOVV	old+16(FP), R6
406	MOVW	size+24(FP), R7
407	MOVV	$SYS_rt_sigprocmask, R11
408	SYSCALL
409	MOVW	$-4096, R5
410	BGEU	R5, R4, 2(PC)
411	MOVV	R0, 0xf1(R0)	// crash
412	RET
413
414// func rt_sigaction(sig uintptr, new, old *sigactiont, size uintptr) int32
415TEXT runtime·rt_sigaction(SB),NOSPLIT|NOFRAME,$0-36
416	MOVV	sig+0(FP), R4
417	MOVV	new+8(FP), R5
418	MOVV	old+16(FP), R6
419	MOVV	size+24(FP), R7
420	MOVV	$SYS_rt_sigaction, R11
421	SYSCALL
422	MOVW	R4, ret+32(FP)
423	RET
424
425// func sigfwd(fn uintptr, sig uint32, info *siginfo, ctx unsafe.Pointer)
426TEXT runtime·sigfwd(SB),NOSPLIT,$0-32
427	MOVW	sig+8(FP), R4
428	MOVV	info+16(FP), R5
429	MOVV	ctx+24(FP), R6
430	MOVV	fn+0(FP), R20
431	JAL	(R20)
432	RET
433
434// func sigtramp(signo, ureg, ctxt unsafe.Pointer)
435TEXT runtime·sigtramp(SB),NOSPLIT|TOPFRAME,$168
436	MOVW	R4, (1*8)(R3)
437	MOVV	R5, (2*8)(R3)
438	MOVV	R6, (3*8)(R3)
439
440	// Save callee-save registers in the case of signal forwarding.
441	// Please refer to https://golang.org/issue/31827 .
442	SAVE_R22_TO_R31((4*8))
443	SAVE_F24_TO_F31((14*8))
444
445	// this might be called in external code context,
446	// where g is not set.
447	MOVB	runtime·iscgo(SB), R4
448	BEQ	R4, 2(PC)
449	JAL	runtime·load_g(SB)
450
451	MOVV	$runtime·sigtrampgo(SB), R4
452	JAL	(R4)
453
454	// Restore callee-save registers.
455	RESTORE_R22_TO_R31((4*8))
456	RESTORE_F24_TO_F31((14*8))
457
458	RET
459
460// func cgoSigtramp()
461TEXT runtime·cgoSigtramp(SB),NOSPLIT,$0
462	JMP	runtime·sigtramp(SB)
463
464// func sysMmap(addr unsafe.Pointer, n uintptr, prot, flags, fd int32, off uint32) (p unsafe.Pointer, err int)
465TEXT runtime·sysMmap(SB),NOSPLIT|NOFRAME,$0
466	MOVV	addr+0(FP), R4
467	MOVV	n+8(FP), R5
468	MOVW	prot+16(FP), R6
469	MOVW	flags+20(FP), R7
470	MOVW	fd+24(FP), R8
471	MOVW	off+28(FP), R9
472
473	MOVV	$SYS_mmap, R11
474	SYSCALL
475	MOVW	$-4096, R5
476	BGEU	R5, R4, ok
477	MOVV	$0, p+32(FP)
478	SUBVU	R4, R0, R4
479	MOVV	R4, err+40(FP)
480	RET
481ok:
482	MOVV	R4, p+32(FP)
483	MOVV	$0, err+40(FP)
484	RET
485
486// Call the function stored in _cgo_mmap using the GCC calling convention.
487// This must be called on the system stack.
488// func callCgoMmap(addr unsafe.Pointer, n uintptr, prot, flags, fd int32, off uint32) uintptr
489TEXT runtime·callCgoMmap(SB),NOSPLIT,$0
490	MOVV	addr+0(FP), R4
491	MOVV	n+8(FP), R5
492	MOVW	prot+16(FP), R6
493	MOVW	flags+20(FP), R7
494	MOVW	fd+24(FP), R8
495	MOVW	off+28(FP), R9
496	MOVV	_cgo_mmap(SB), R13
497	SUBV	$16, R3		// reserve 16 bytes for sp-8 where fp may be saved.
498	JAL	(R13)
499	ADDV	$16, R3
500	MOVV	R4, ret+32(FP)
501	RET
502
503// func sysMunmap(addr unsafe.Pointer, n uintptr)
504TEXT runtime·sysMunmap(SB),NOSPLIT|NOFRAME,$0
505	MOVV	addr+0(FP), R4
506	MOVV	n+8(FP), R5
507	MOVV	$SYS_munmap, R11
508	SYSCALL
509	MOVW	$-4096, R5
510	BGEU	R5, R4, 2(PC)
511	MOVV	R0, 0xf3(R0)	// crash
512	RET
513
514// Call the function stored in _cgo_munmap using the GCC calling convention.
515// This must be called on the system stack.
516// func callCgoMunmap(addr unsafe.Pointer, n uintptr)
517TEXT runtime·callCgoMunmap(SB),NOSPLIT,$0
518	MOVV	addr+0(FP), R4
519	MOVV	n+8(FP), R5
520	MOVV	_cgo_munmap(SB), R13
521	SUBV	$16, R3		// reserve 16 bytes for sp-8 where fp may be saved.
522	JAL	(R13)
523	ADDV	$16, R3
524	RET
525
526// func madvise(addr unsafe.Pointer, n uintptr, flags int32)
527TEXT runtime·madvise(SB),NOSPLIT|NOFRAME,$0
528	MOVV	addr+0(FP), R4
529	MOVV	n+8(FP), R5
530	MOVW	flags+16(FP), R6
531	MOVV	$SYS_madvise, R11
532	SYSCALL
533	MOVW	R4, ret+24(FP)
534	RET
535
536// func futex(addr unsafe.Pointer, op int32, val uint32, ts, addr2 unsafe.Pointer, val3 uint32) int32
537TEXT runtime·futex(SB),NOSPLIT|NOFRAME,$0
538	MOVV	addr+0(FP), R4
539	MOVW	op+8(FP), R5
540	MOVW	val+12(FP), R6
541	MOVV	ts+16(FP), R7
542	MOVV	addr2+24(FP), R8
543	MOVW	val3+32(FP), R9
544	MOVV	$SYS_futex, R11
545	SYSCALL
546	MOVW	R4, ret+40(FP)
547	RET
548
549// int64 clone(int32 flags, void *stk, M *mp, G *gp, void (*fn)(void));
550TEXT runtime·clone(SB),NOSPLIT|NOFRAME,$0
551	MOVW	flags+0(FP), R4
552	MOVV	stk+8(FP), R5
553
554	// Copy mp, gp, fn off parent stack for use by child.
555	// Careful: Linux system call clobbers ???.
556	MOVV	mp+16(FP), R23
557	MOVV	gp+24(FP), R24
558	MOVV	fn+32(FP), R25
559
560	MOVV	R23, -8(R5)
561	MOVV	R24, -16(R5)
562	MOVV	R25, -24(R5)
563	MOVV	$1234, R23
564	MOVV	R23, -32(R5)
565
566	MOVV	$SYS_clone, R11
567	SYSCALL
568
569	// In parent, return.
570	BEQ	R4, 3(PC)
571	MOVW	R4, ret+40(FP)
572	RET
573
574	// In child, on new stack.
575	MOVV	-32(R3), R23
576	MOVV	$1234, R19
577	BEQ	R23, R19, 2(PC)
578	MOVV	R0, 0(R0)
579
580	// Initialize m->procid to Linux tid
581	MOVV	$SYS_gettid, R11
582	SYSCALL
583
584	MOVV	-24(R3), R25		// fn
585	MOVV	-16(R3), R24		// g
586	MOVV	-8(R3), R23		// m
587
588	BEQ	R23, nog
589	BEQ	R24, nog
590
591	MOVV	R4, m_procid(R23)
592
593	// TODO: setup TLS.
594
595	// In child, set up new stack
596	MOVV	R23, g_m(R24)
597	MOVV	R24, g
598	//CALL	runtime·stackcheck(SB)
599
600nog:
601	// Call fn
602	JAL	(R25)
603
604	// It shouldn't return.	 If it does, exit that thread.
605	MOVW	$111, R4
606	MOVV	$SYS_exit, R11
607	SYSCALL
608	JMP	-3(PC)	// keep exiting
609
610// func sigaltstack(new, old *stackt)
611TEXT runtime·sigaltstack(SB),NOSPLIT|NOFRAME,$0
612	MOVV	new+0(FP), R4
613	MOVV	old+8(FP), R5
614	MOVV	$SYS_sigaltstack, R11
615	SYSCALL
616	MOVW	$-4096, R5
617	BGEU	R5, R4, 2(PC)
618	MOVV	R0, 0xf1(R0)	// crash
619	RET
620
621// func osyield()
622TEXT runtime·osyield(SB),NOSPLIT|NOFRAME,$0
623	MOVV	$SYS_sched_yield, R11
624	SYSCALL
625	RET
626
627// func sched_getaffinity(pid, len uintptr, buf *uintptr) int32
628TEXT runtime·sched_getaffinity(SB),NOSPLIT|NOFRAME,$0
629	MOVV	pid+0(FP), R4
630	MOVV	len+8(FP), R5
631	MOVV	buf+16(FP), R6
632	MOVV	$SYS_sched_getaffinity, R11
633	SYSCALL
634	MOVW	R4, ret+24(FP)
635	RET
636
637// func sbrk0() uintptr
638TEXT runtime·sbrk0(SB),NOSPLIT|NOFRAME,$0-8
639	// Implemented as brk(NULL).
640	MOVV	$0, R4
641	MOVV	$SYS_brk, R11
642	SYSCALL
643	MOVV	R4, ret+0(FP)
644	RET
645
646TEXT runtime·access(SB),$0-20
647	MOVV	R0, 2(R0) // unimplemented, only needed for android; declared in stubs_linux.go
648	MOVW	R0, ret+16(FP) // for vet
649	RET
650
651TEXT runtime·connect(SB),$0-28
652	MOVV	R0, 2(R0) // unimplemented, only needed for android; declared in stubs_linux.go
653	MOVW	R0, ret+24(FP) // for vet
654	RET
655
656TEXT runtime·socket(SB),$0-20
657	MOVV	R0, 2(R0) // unimplemented, only needed for android; declared in stubs_linux.go
658	MOVW	R0, ret+16(FP) // for vet
659	RET
660