xref: /netbsd-src/lib/libc/arch/arm/gen/_setjmp.S (revision c7c727fae85036860d5bb848f2730ff419e2b060)
1/*	$NetBSD: _setjmp.S,v 1.12 2013/04/19 13:45:45 matt 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#ifdef __ARM_EABI__
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 NOT restored.
54 *
55 * Note: r0 is the return value
56 *       r1-r3,ip are scratch registers in functions
57 */
58
59ENTRY(_setjmp)
60	ldr	r1, .L_setjmp_magic
61
62#ifdef __ARM_EABI__
63	ldr	r2, .Lfpu_present
64#ifdef PIC
65	GOT_INIT(r3, .L_setjmp_got, .L_setjmp_gotinit)
66	ldr	r2, [r2, r3]
67#else
68	ldr	r2, [r2]
69#endif
70	teq	r2, #0		/* do we have a FPU? */
71	beq	1f		/*   no, don't save VFP registers */
72
73	orr	r1, r1, #(_JB_MAGIC__SETJMP ^ _JB_MAGIC__SETJMP_VFP)
74				/* change magic to VFP magic */
75	add	r2, r0, #(_JB_REG_D8 * 4)
76	vstmia	r2, {d8-d15}
77	vmrs	r2, fpscr
78	str	r2, [r0, #(_JB_REG_FPSCR * 4)]
791:
80#endif /* __ARM_EABI__ */
81
82	str	r1, [r0]
83
84	add	r0, r0, #(_JB_REG_R4 * 4)
85	/* Store integer registers */
86        stmia	r0, {r4-r14}
87
88        mov	r0, #0x00000000
89        RET
90
91.L_setjmp_magic:
92	.word	_JB_MAGIC__SETJMP
93#ifdef __ARM_EABI__
94	GOT_INITSYM(.L_setjmp_got, .L_setjmp_gotinit)
95.Lfpu_present:
96	.word	PIC_SYM(_libc_arm_fpu_present, GOTOFF)
97#endif /* __ARM_EABI__ */
98
99ENTRY(_longjmp)
100	ldr	r2, [r0]			/* get magic from jmp_buf */
101	bic	r3, r2, #(_JB_MAGIC__SETJMP ^ _JB_MAGIC__SETJMP_VFP)
102						/* ignore VFP-ness of magic */
103	ldr	ip, .L_setjmp_magic		/* load magic */
104	teq	ip, r3				/* magic correct? */
105	bne	botch				/*   no, botch */
106
107#ifdef __ARM_EABI__
108	teq	r3, r2				/* did magic change? */
109	beq	1f				/*   no, don't restore VFP */
110	add	ip, r0, #(_JB_REG_D8 * 4)
111	vldmia	ip, {d8-d15}
112	ldr	ip, [r0, #(_JB_REG_FPSCR * 4)]
113	vmsr	fpscr, ip
1141:
115#endif /* __ARM_EABI__ */
116
117	add	r0, r0, #(_JB_REG_R4 * 4)
118       	/* Restore integer registers */
119        ldmia	r0, {r4-r14}
120
121	/* Validate sp and r14 */
122	teq	sp, #0
123	teqne	r14, #0
124	beq	botch
125
126	/* Set return value */
127	movs	r0, r1
128	moveq	r0, #0x00000001
129	RET
130
131	/* validation failed, die die die. */
132botch:
133	bl	PIC_SYM(_C_LABEL(longjmperror), PLT)
134	bl	PIC_SYM(_C_LABEL(abort), PLT)
135	b	. - 8		/* Cannot get here */
136