xref: /freebsd/sys/i386/include/asm.h (revision 193d9e768ba63fcfb187cfd17f461f7d41345048)
1 /*-
2  * Copyright (c) 1990 The Regents of the University of California.
3  * All rights reserved.
4  *
5  * This code is derived from software contributed to Berkeley by
6  * William Jolitz.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. Neither the name of the University nor the names of its contributors
17  *    may be used to endorse or promote products derived from this software
18  *    without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  *
32  *	from: @(#)DEFS.h	5.1 (Berkeley) 4/23/90
33  * $FreeBSD$
34  */
35 
36 #ifndef _MACHINE_ASM_H_
37 #define	_MACHINE_ASM_H_
38 
39 #include <sys/cdefs.h>
40 
41 #ifdef PIC
42 #define	PIC_PROLOGUE	\
43 	pushl	%ebx;	\
44 	call	1f;	\
45 1:			\
46 	popl	%ebx;	\
47 	addl	$_GLOBAL_OFFSET_TABLE_+[.-1b],%ebx
48 #define	PIC_EPILOGUE	\
49 	popl	%ebx
50 #define	PIC_PLT(x)	x@PLT
51 #define	PIC_GOT(x)	x@GOT(%ebx)
52 #define	PIC_GOTOFF(x)	x@GOTOFF(%ebx)
53 #else
54 #define	PIC_PROLOGUE
55 #define	PIC_EPILOGUE
56 #define	PIC_PLT(x)	x
57 #define	PIC_GOTOFF(x)	x
58 #endif
59 
60 /*
61  * CNAME and HIDENAME manage the relationship between symbol names in C
62  * and the equivalent assembly language names.  CNAME is given a name as
63  * it would be used in a C program.  It expands to the equivalent assembly
64  * language name.  HIDENAME is given an assembly-language name, and expands
65  * to a possibly-modified form that will be invisible to C programs.
66  */
67 #define CNAME(csym)		csym
68 #define HIDENAME(asmsym)	.asmsym
69 
70 /* XXX should use .p2align 4,0x90 for -m486. */
71 #define _START_ENTRY	.text; .p2align 2,0x90
72 
73 #define _ENTRY(x)	_START_ENTRY; \
74 			.globl CNAME(x); .type CNAME(x),@function; CNAME(x):
75 #define	END(x)		.size x, . - x
76 
77 #ifdef PROF
78 #define	ALTENTRY(x)	_ENTRY(x); \
79 			pushl %ebp; movl %esp,%ebp; \
80 			call PIC_PLT(HIDENAME(mcount)); \
81 			popl %ebp; \
82 			jmp 9f
83 #define	ENTRY(x)	_ENTRY(x); \
84 			pushl %ebp; movl %esp,%ebp; \
85 			call PIC_PLT(HIDENAME(mcount)); \
86 			popl %ebp; \
87 			9:
88 #else
89 #define	ALTENTRY(x)	_ENTRY(x)
90 #define	ENTRY(x)	_ENTRY(x)
91 #endif
92 
93 /*
94  * WEAK_REFERENCE(): create a weak reference alias from sym.
95  * The macro is not a general asm macro that takes arbitrary names,
96  * but one that takes only C names. It does the non-null name
97  * translation inside the macro.
98  */
99 
100 #define	WEAK_REFERENCE(sym, alias)					\
101 	.weak CNAME(alias);						\
102 	.equ CNAME(alias),CNAME(sym)
103 
104 /*
105  * STRONG_ALIAS: create a strong alias.
106  */
107 #define	STRONG_ALIAS(alias,sym)						\
108 	.globl alias;							\
109 	alias = sym
110 
111 #define RCSID(x)	.text; .asciz x
112 
113 #undef __FBSDID
114 #if !defined(lint) && !defined(STRIP_FBSDID)
115 #define __FBSDID(s)	.ident s
116 #else
117 #define __FBSDID(s)	/* nothing */
118 #endif /* not lint and not STRIP_FBSDID */
119 
120 #endif /* !_MACHINE_ASM_H_ */
121