1/*	$OpenBSD: DEFS.h,v 1.2 2023/12/13 09:01:25 miod Exp $	*/
2
3/*
4 * Copyright (c) 1998-2002 Michael Shalayeff
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 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF MIND
22 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26 */
27
28#include <machine/asm.h>
29
30#define	END(x)	EXIT(x)
31
32/*
33 * We define a hidden alias with the prefix "_libc_" for each global symbol
34 * that may be used internally.  By referencing _libc_x instead of x, other
35 * parts of libc prevent overriding by the application and avoid unnecessary
36 * relocations.
37 */
38#define _HIDDEN(x)		_libc_##x
39#define _HIDDEN_ALIAS(x,y)			\
40	STRONG_ALIAS(_HIDDEN(x),y)		!\
41	.hidden _HIDDEN(x)
42#define _HIDDEN_FALIAS(x,y)			\
43	_HIDDEN_ALIAS(x,y)			!\
44	.type _HIDDEN(x),@function
45
46/*
47 * For functions implemented in ASM that aren't syscalls.
48 *   END_STRONG(x)	Like DEF_STRONG() in C; for standard/reserved C names
49 *   END_WEAK(x)	Like DEF_WEAK() in C; for non-ISO C names
50 *   ALTEND_STRONG(x) and ALTEND_WEAK()
51 *			Matching macros for ALTENTRY functions
52 *   END_BUILTIN(x)	If compiling with clang, then just END() and
53 *			mark it .protected, else be like END_STRONG();
54 *			for clang builtins like memcpy
55 *
56 * If a 'BUILTIN' function needs be referenced by other ASM code, then use
57 *   _BUILTIN(x)	If compiled with clang, then just x, otherwise
58 *			_HIDDEN(x)
59 *
60 *   _END(x)		Set a size on a symbol, like END(), but even for
61 *			symbols with no matching ENTRY().  (On alpha and
62 *			mips64, END() generates .end which requires a
63 *			matching .ent from ENTRY())
64 */
65#define	END_STRONG(x)	END(x) ! _HIDDEN_FALIAS(x,x) ! _END(_HIDDEN(x))
66#define	END_WEAK(x)	END_STRONG(x) ! .weak x
67#define	ALTEND_STRONG(x) _HIDDEN_FALIAS(x,x) ! _END(_HIDDEN(x))
68#define	ALTEND_WEAK(x)	ALTEND_STRONG(x) ! .weak x
69
70#ifdef __clang__
71#define	END_BUILTIN(x)	END(x) ! .protected x
72#define	_BUILTIN(x)	x
73#else
74#define	END_BUILTIN(x)	END_STRONG(x)
75#define	_BUILTIN(x)	_HIDDEN(x)
76#endif
77
78#define _END(x)		.size x, . - x
79
80#define PINSYSCALL(sysno, label)			\
81	.pushsection .openbsd.syscalls,"",@progbits	!\
82	.p2align 2					!\
83	.long label					!\
84	.long sysno					!\
85	.popsection
86