xref: /netbsd-src/lib/libc/arch/arm/gen/setjmp.S (revision ababa08f7df689c506f61871a408d771276359ae)
1/*	$NetBSD: setjmp.S,v 1.19 2024/05/06 06:57:32 skrll Exp $	*/
2
3/*
4 * Copyright (c) 1997 Mark Brinicombe
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 * 3. All advertising materials mentioning features or use of this software
16 *    must display the following acknowledgement:
17 *	This product includes software developed by Mark Brinicombe
18 * 4. Neither the name of the University nor the names of its contributors
19 *    may be used to endorse or promote products derived from this software
20 *    without specific prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 * SUCH DAMAGE.
33 */
34
35#if !defined(__SOFTFP__) && !defined(__VFP_FP__) && !defined(__ARM_PCS)
36#error FPA is not supported anymore
37#endif
38
39#if defined(__ARM_EABI__) && !defined(__ARM_PCS_VFP)
40	.fpu	vfp
41#endif
42
43#include <machine/asm.h>
44#include <machine/setjmp.h>
45
46/*
47 * C library -- setjmp, longjmp
48 *
49 *	longjmp(a,v)
50 * will generate a "return(v)" from the last call to
51 *	setjmp(a)
52 * by restoring registers from the stack.
53 * The previous signal state is restored.
54 */
55
56ENTRY(__setjmp14)
57	/* Get the signal mask. */
58	push	{r0-r2, lr}
59#if !defined(__thumb__)
60	adds	r2, r0, #(_JB_SIGMASK * 4)
61#else
62	mov	r2, r0
63	adds	r2, r2, #(_JB_SIGMASK * 4)
64#endif
65	movs	r1, #0
66	movs	r0, #0
67	bl	PLT_SYM(_C_LABEL(__sigprocmask14))
68#if !defined(__thumb__) || defined(_ARM_ARCH_T2)
69	pop	{r0-r2, lr}
70#else
71	pop	{r0-r3}
72	mov	lr, r3
73#endif
74
75	ldr	r1, .Lsetjmp_magic
76
77#if defined(__ARM_EABI__) && (!defined(__thumb__) || defined(_ARM_ARCH_T2))
78	ldr	r2, .Lfpu_present
79#ifdef __PIC__
80	add	r2, r2, pc	/* pc = &.LPIC0 */
81#endif
82	ldr	r2, [r2]
83.LPIC0:
84#if defined(__thumb__) && defined(_ARM_ARCH_T2)
85	cbz	r2, 1f		/* don't save if we don't have a FPU */
86#else
87	cmp	r2, #0		/* do we have a FPU? */
88	beq	1f		/*   no, don't save VFP registers */
89#endif
90
91	orrs	r1, r1, #(_JB_MAGIC_SETJMP ^ _JB_MAGIC_SETJMP_VFP)
92				/* change magic to VFP magic */
93	adds	r2, r0, #(_JB_REG_D8 * 4)
94	vstmia	r2, {d8-d15}
95	vmrs	r2, fpscr
96	str	r2, [r0, #(_JB_REG_FPSCR * 4)]
971:
98#endif /* __ARM_EABI__ && (!__thumb__ || _ARM_ARCH_T2) */
99
100	str	r1, [r0]		/* store magic */
101
102	/* Store integer registers */
103	adds	r0, r0, #(_JB_REG_R4 * 4)
104#if !defined(__thumb__)
105	stmia	r0!, {r4-lr}
106#else
107	stmia	r0!, {r4-r7}
108	mov	r2, r8
109	mov	r3, r9
110	stmia	r0!, {r2-r3}
111	mov	r2, r10
112	mov	r3, r11
113	stmia	r0!, {r2-r3}
114	mov	r2, sp
115	mov	r3, lr
116	str	r2, [r0, #4]
117	str	r3, [r0, #8]
118#endif
119	movs	r0, #0
120	RET
121
122#if defined(__ARM_EABI__) && (!defined(__thumb__) || defined(_ARM_ARCH_T2))
123	.align	0
124.Lfpu_present:
125	.word	REL_SYM(_libc_arm_fpu_present, .LPIC0)
126#endif /* __ARM_EABI__ && (!__thumb__ || _ARM_ARCH_T2) */
127END(__setjmp14)
128
129ENTRY(__longjmp14)
130#if !defined(__thumb__) || defined(_ARM_ARCH_T2)
131	ldr	r2, [r0]
132	ldr	ip, .Lsetjmp_magic
133	bic	r3, r2, #(_JB_MAGIC_SETJMP ^ _JB_MAGIC_SETJMP_VFP)
134#else
135	ldr	r3, .Lsetjmp_magic
136	mov	ip, r3
137	ldr	r3, [r0]
138	movs	r2, #(_JB_MAGIC_SETJMP ^ _JB_MAGIC_SETJMP_VFP)
139	bics	r3, r2
140	/* r2 is not the magic but we don't need it since we can't do VFP */
141#endif
142	cmp	r3, ip
143	bne	.Lbotch
144
145	/* Validate sp and lr */
146	ldr	r2, [r0, #(_JB_REG_R13 * 4)]
147#if defined(__thumb__) && defined(_ARM_ARCH_T2)
148	cbz	r2, .Lbotch
149#else
150	cmp	r2, #0
151	beq	.Lbotch
152#endif
153
154	ldr	r3, [r0, #(_JB_REG_R14 * 4)]
155#if defined(__thumb__) && defined(_ARM_ARCH_T2)
156	cbz	r3, .Lbotch
157#else
158	cmp	r3, #0
159	beq	.Lbotch
160#endif
161	mov	sp, r2
162	mov	lr, r3
163
164	/* Restore the signal mask. */
165	push	{r0-r2, lr}
166	movs	r2, #0
167#if !defined(__thumb__)
168	adds	r1, r0, #(_JB_SIGMASK * 4)
169#else
170	mov	r1, r0
171	adds	r1, r1, #(_JB_SIGMASK * 4)
172#endif
173	movs	r0, #3				/* SIG_SETMASK */
174	bl	PLT_SYM(_C_LABEL(__sigprocmask14))
175#if !defined(__thumb__) || defined(_ARM_ARCH_T2)
176	pop	{r0-r2, lr}
177#else
178	pop	{r0-r3}
179	mov	lr, r3
180#endif
181
182#if defined(__ARM_EABI__) && (!defined(__thumb__) || defined(_ARM_ARCH_T2))
183	tst	r2, #(_JB_MAGIC_SETJMP ^ _JB_MAGIC_SETJMP_VFP)
184						/* is this a VFP magic? */
185	beq	1f				/*   no, don't restore VFP */
186	adds	r2, r0, #(_JB_REG_D8 * 4)
187	vldmia	r2, {d8-d15}
188	ldr	r2, [r0, #(_JB_REG_FPSCR * 4)]
189	vmsr	fpscr, r2
1901:
191#endif /* __ARM_EABI__ && (!__thumb__ || _ARM_ARCH_T2) */
192
193	adds	r0, r0, #(_JB_REG_R4 * 4)
194	/* Restore integer registers */
195#if !defined(__thumb__) || defined(_ARM_ARCH_T2)
196	ldmia	r0!, {r4-r12}
197#else
198	ldmia	r0!, {r4-r7}
199	ldmia	r0!, {r2-r3}
200	mov	r8, r2
201	mov	r9, r3
202	ldmia	r0!, {r2-r3}
203	mov	r10, r2
204	mov	r11, r3
205	adds	r0, r0, #4	/* skip ip(r12) */
206#endif
207
208	/* Set return value */
209	movs	r0, r1
210#if !defined(__thumb__)
211	moveq	r0, #1
212#else
213	bne	1f
214	movs	r0, #1
2151:
216#endif
217	RET
218
219	/* validation failed, die die die. */
220.Lbotch:
221	bl	PLT_SYM(_C_LABEL(longjmperror))
222	bl	PLT_SYM(_C_LABEL(abort))
2231:	b	1b		/* Cannot get here */
224
225	.align	0
226.Lsetjmp_magic:
227	.word	_JB_MAGIC_SETJMP
228END(__longjmp14)
229