1/* Save current context and install the given one.
2   Copyright (C) 2005-2022 Free Software Foundation, Inc.
3   This file is part of the GNU C Library.
4
5   The GNU C Library is free software; you can redistribute it and/or
6   modify it under the terms of the GNU Lesser General Public
7   License as published by the Free Software Foundation; either
8   version 2.1 of the License, or (at your option) any later version.
9
10   The GNU C Library is distributed in the hope that it will be useful,
11   but WITHOUT ANY WARRANTY; without even the implied warranty of
12   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13   Lesser General Public License for more details.
14
15   You should have received a copy of the GNU Lesser General Public
16   License along with the GNU C Library; if not, see
17   <https://www.gnu.org/licenses/>.  */
18
19#include <sysdep.h>
20
21#include "ucontext_i.h"
22
23/*  int __swapcontext (ucontext_t *ouc, const ucontext_t *uc);  */
24
25	.text
26	.align  5
27ENTRY(__swapcontext)
28
29	/* Return value of getcontext.  R0 is the only register whose
30	   value is not preserved.  */
31	mov	#0, r0
32	mov.l	r0, @(oR0,r4)
33	mov.l	r1, @(oR1,r4)
34	mov.l	r2, @(oR2,r4)
35	mov.l	r3, @(oR3,r4)
36	mov.l	r4, @(oR4,r4)
37	mov.l	r5, @(oR5,r4)
38	mov.l	r6, @(oR6,r4)
39	mov.l	r7, @(oR7,r4)
40	mov	r4, r0
41	add	#(oMACL+4), r0
42	sts.l	macl, @-r0
43	sts.l	mach, @-r0
44	stc.l	gbr, @-r0
45
46	/* Save T flag to SR.  */
47	movt	r1
48	mov.l	r1, @-r0
49	sts.l	pr, @-r0
50
51	/* The return address of getcontext is the restart pc.  */
52	sts.l	pr, @-r0
53
54	mov.l	r15, @-r0
55	mov.l	r14, @-r0
56	mov.l	r13, @-r0
57	mov.l	r12, @-r0
58	mov.l	r11, @-r0
59	mov.l	r10, @-r0
60	mov.l	r9, @-r0
61	mov.l	r8, @-r0
62
63#ifdef __SH_FPU_ANY__
64	mov	r4, r0
65	/* We need 2 add instruction because oFPUL+4 >= 127.  */
66	add	#124,r0
67	add	#(oFPUL+4-124),r0
68	sts.l	fpul, @-r0
69	sts.l	fpscr, @-r0
70	frchg
71	fmov.s	fr15, @-r0
72	fmov.s	fr14, @-r0
73	fmov.s	fr13, @-r0
74	fmov.s	fr12, @-r0
75	fmov.s	fr11, @-r0
76	fmov.s	fr10, @-r0
77	fmov.s	fr9, @-r0
78	fmov.s	fr8, @-r0
79	fmov.s	fr7, @-r0
80	fmov.s	fr6, @-r0
81	fmov.s	fr5, @-r0
82	fmov.s	fr4, @-r0
83	fmov.s	fr3, @-r0
84	fmov.s	fr2, @-r0
85	fmov.s	fr1, @-r0
86	fmov.s	fr0, @-r0
87	frchg
88	fmov.s	fr15, @-r0
89	fmov.s	fr14, @-r0
90	fmov.s	fr13, @-r0
91	fmov.s	fr12, @-r0
92	fmov.s	fr11, @-r0
93	fmov.s	fr10, @-r0
94	fmov.s	fr9, @-r0
95	fmov.s	fr8, @-r0
96	fmov.s	fr7, @-r0
97	fmov.s	fr6, @-r0
98	fmov.s	fr5, @-r0
99	fmov.s	fr4, @-r0
100	fmov.s	fr3, @-r0
101	fmov.s	fr2, @-r0
102	fmov.s	fr1, @-r0
103	fmov.s	fr0, @-r0
104#endif /* __SH_FPU_ANY__ */
105
106	mov	r5, r8
107
108	/* sigprocmask (SIG_SETMASK, &uc->uc_sigmask, &ouc->uc_sigmask).  */
109	mov	#oSIGMASK, r1
110	extu.b	r1, r1
111	add	r1, r5
112	mov	r4, r6
113	add	r1, r6
114	mov	#SIG_SETMASK, r4
115	mov	#+SYS_ify(sigprocmask), r3
116	trapa	#0x13
117	mov     r0, r1
118	mov	#-12, r2
119	shad	r2, r1
120	not	r1, r1			// r1=0 means r0 = -1 to -4095
121	tst	r1, r1			// i.e. error in linux
122	bf	.Lswapcontext_restore
123.Lsyscall_error:
124	SYSCALL_ERROR_HANDLER
125.Lpseudo_end:
126	rts
127	 nop
128.Lswapcontext_restore:
129#ifdef __SH_FPU_ANY__
130	mov	r8, r0
131	add	#(oFR0),r0
132	fmov.s	@r0+, fr0
133	fmov.s	@r0+, fr1
134	fmov.s	@r0+, fr2
135	fmov.s	@r0+, fr3
136	fmov.s	@r0+, fr4
137	fmov.s	@r0+, fr5
138	fmov.s	@r0+, fr6
139	fmov.s	@r0+, fr7
140	fmov.s	@r0+, fr8
141	fmov.s	@r0+, fr9
142	fmov.s	@r0+, fr10
143	fmov.s	@r0+, fr11
144	fmov.s	@r0+, fr12
145	fmov.s	@r0+, fr13
146	fmov.s	@r0+, fr14
147	fmov.s	@r0+, fr15
148	frchg
149	fmov.s	@r0+, fr0
150	fmov.s	@r0+, fr1
151	fmov.s	@r0+, fr2
152	fmov.s	@r0+, fr3
153	fmov.s	@r0+, fr4
154	fmov.s	@r0+, fr5
155	fmov.s	@r0+, fr6
156	fmov.s	@r0+, fr7
157	fmov.s	@r0+, fr8
158	fmov.s	@r0+, fr9
159	fmov.s	@r0+, fr10
160	fmov.s	@r0+, fr11
161	fmov.s	@r0+, fr12
162	fmov.s	@r0+, fr13
163	fmov.s	@r0+, fr14
164	fmov.s	@r0+, fr15
165	frchg
166	lds.l	@r0+, fpscr
167	lds.l	@r0+, fpul
168#endif /* __SH_FPU_ANY__ */
169
170	mov	r8, r0
171	add	#(oPC), r0
172	mov.l	@r0+, r2
173	lds.l	@r0+, pr
174
175	/* Restore T frag.  */
176	mov.l	@r0+, r1
177	shlr	r1
178	/* Skip GBR which is used for thread pointer.  */
179	add	#4, r0
180
181	lds.l	@r0+, mach
182	lds.l	@r0+, macl
183
184	mov	r8, r0
185	add	#(oR9), r0
186	mov.l	@r0+, r9
187	mov.l	@r0+, r10
188	mov.l	@r0+, r11
189	mov.l	@r0+, r12
190	mov.l	@r0+, r13
191	mov.l	@r0+, r14
192	mov.l	@r0+, r15
193
194	mov	r8, r0
195	mov.l	@(oR0,r0), r1
196	mov.l	r1, @-r15
197	cfi_adjust_cfa_offset(4)
198	cfi_rel_offset (r1, 0)
199	mov.l	r2, @-r15
200	cfi_adjust_cfa_offset(4)
201	cfi_rel_offset (r2, 0)
202
203	mov.l	@(oR1,r0), r1
204	mov.l	@(oR2,r0), r2
205	mov.l	@(oR3,r0), r3
206	mov.l	@(oR4,r0), r4
207	mov.l	@(oR5,r0), r5
208	mov.l	@(oR6,r0), r6
209	mov.l	@(oR7,r0), r7
210	mov.l	@(oR8,r0), r8
211	mov.l	@r15+, r0
212	cfi_adjust_cfa_offset(-4)
213	jmp	@r0
214	 mov.l	@r15+, r0
215
216PSEUDO_END(__swapcontext)
217
218weak_alias (__swapcontext, swapcontext)
219