xref: /freebsd/sys/arm64/include/setjmp.h (revision 8657387683946d0c03e09fe77029edfe309eeb20)
1 /*-
2  * Copyright (c) 2014 Andrew Turner
3  * Copyright (c) 2014-2015 The FreeBSD Foundation
4  * All rights reserved.
5  *
6  * This software was developed by Andrew Turner under
7  * sponsorship from the FreeBSD Foundation.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
19  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
22  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28  * SUCH DAMAGE.
29  *
30  * $FreeBSD$
31  */
32 
33 #ifndef _MACHINE_SETJMP_H_
34 #define	_MACHINE_SETJMP_H_
35 
36 #include <sys/cdefs.h>
37 
38 /*
39  * We need to store:
40  *  - A magic value to differentiate the buffers
41  *  - The stack pointer
42  *  - The link register
43  *  - 11 general purpose registers
44  *  - 8 floating point registers
45  *  - The signal mask (128 bits)
46  * i.e. 24 64-bit words, round this up to 31(+1) 128-bit words to allow for
47  * CPU extensions with larger registers and stronger alignment requirements.
48  *
49  * The registers to save are: r19 to r29, and d8 to d15.
50  */
51 #define	_JBLEN		31
52 #define	_JB_SIGMASK	22
53 
54 /* This should only be needed in libc and may change */
55 #ifdef __ASSEMBLER__
56 #define	_JB_MAGIC__SETJMP	0xfb5d25837d7ff700
57 #define	_JB_MAGIC_SETJMP	0xfb5d25837d7ff701
58 #endif
59 
60 #ifndef __ASSEMBLER__
61 /*
62  * jmp_buf and sigjmp_buf are encapsulated in different structs to force
63  * compile-time diagnostics for mismatches.  The structs are the same
64  * internally to avoid some run-time errors for mismatches.
65  */
66 #if __BSD_VISIBLE || __POSIX_VISIBLE || __XSI_VISIBLE
67 typedef struct _sigjmp_buf { __int128_t _sjb[_JBLEN + 1]; } sigjmp_buf[1];
68 #endif
69 
70 typedef struct _jmp_buf { __int128_t _jb[_JBLEN + 1]; } jmp_buf[1];
71 #endif /* __ASSEMBLER__ */
72 
73 #endif /* !_MACHINE_SETJMP_H_ */
74