1/* longjmp for ARM.
2   Copyright (C) 1997-2022 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#include <stap-probe.h>
21#include <bits/setjmp.h>
22#include <rtld-global-offsets.h>
23#include <arm-features.h>
24
25/* __longjmp(jmpbuf, val) */
26
27ENTRY (__longjmp)
28	mov	ip, r0
29
30#ifdef CHECK_SP
31	ldr	r4, [ip]	/* jmpbuf's sp */
32	cfi_undefined (r4)
33#ifdef PTR_DEMANGLE
34	PTR_DEMANGLE (r4, r4, a3, a4)
35#endif
36	CHECK_SP (r4)
37#endif
38
39#ifdef PTR_DEMANGLE
40	ldr	a4, [ip], #4
41	PTR_DEMANGLE (a4, a4, a3, r4)
42	cfi_undefined (r4)
43	ldr	r4, [ip], #4
44	PTR_DEMANGLE2 (r4, r4, a3)
45#else
46	ldr	a4, [ip], #4
47	ldr	r4, [ip], #4
48	cfi_undefined (r4)
49#endif
50	/* longjmp probe expects longjmp first argument (4@r0), second
51	   argument (-4@r1), and target address (4@r4), respectively.  */
52	LIBC_PROBE (longjmp, 3, 4@r0, -4@r1, 4@r4)
53	mov	sp, a4
54	mov	lr, r4
55	ldmia	ip!, JMP_BUF_REGLIST
56	cfi_restore (v1)
57	cfi_restore (v2)
58	cfi_restore (v3)
59	cfi_restore (v4)
60	cfi_restore (v5)
61	cfi_restore (v6)
62	cfi_restore (sl)
63	cfi_restore (fp)
64	cfi_restore (sp)
65	cfi_restore (lr)
66
67#if !defined ARM_ASSUME_NO_IWMMXT || defined __SOFTFP__
68# define NEED_HWCAP 1
69#endif
70
71#ifdef NEED_HWCAP
72# if IS_IN (rtld)
73	LDST_PCREL (ldr, a4, a3, \
74		    C_SYMBOL_NAME(_rtld_local_ro) \
75		    + RTLD_GLOBAL_RO_DL_HWCAP_OFFSET)
76# else
77#  ifdef SHARED
78	LDR_GLOBAL (a4, a3, C_SYMBOL_NAME(_rtld_global_ro), \
79		    RTLD_GLOBAL_RO_DL_HWCAP_OFFSET)
80#  else
81	LDR_GLOBAL (a4, a3, C_SYMBOL_NAME(_dl_hwcap), 0)
82#  endif
83# endif
84#endif
85
86#ifdef __SOFTFP__
87	tst	a4, #HWCAP_ARM_VFP
88	beq	.Lno_vfp
89#endif
90
91	/* Restore the VFP registers.  */
92	/* Following instruction is vldmia ip!, {d8-d15}.  */
93	ldc	p11, cr8, [r12], #64
94.Lno_vfp:
95
96#ifndef ARM_ASSUME_NO_IWMMXT
97	tst	a4, #HWCAP_ARM_IWMMXT
98	beq	.Lno_iwmmxt
99
100	/* Restore the call-preserved iWMMXt registers.  */
101	/* Following instructions are wldrd wr10, [ip], #8 (etc.)  */
102	ldcl	p1, cr10, [r12], #8
103	ldcl	p1, cr11, [r12], #8
104	ldcl	p1, cr12, [r12], #8
105	ldcl	p1, cr13, [r12], #8
106	ldcl	p1, cr14, [r12], #8
107	ldcl	p1, cr15, [r12], #8
108.Lno_iwmmxt:
109#endif
110
111	/* longjmp_target probe expects longjmp first argument (4@r0), second
112	   argument (-4@r1), and target address (4@r14), respectively.  */
113	LIBC_PROBE (longjmp_target, 3, 4@r0, -4@r1, 4@r14)
114
115	movs	r0, r1		/* get the return value in place */
116	it	eq
117	moveq	r0, #1		/* can't let setjmp() return zero! */
118
119	DO_RET(lr)
120
121END (__longjmp)
122