xref: /freebsd/sys/i386/include/asm.h (revision df7f5d4de4592a8948a25ce01e5bddfbb7ce39dc)
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. All advertising materials mentioning features or use of this software
17  *    must display the following acknowledgement:
18  *	This product includes software developed by the University of
19  *	California, Berkeley and its contributors.
20  * 4. Neither the name of the University nor the names of its contributors
21  *    may be used to endorse or promote products derived from this software
22  *    without specific prior written permission.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34  * SUCH DAMAGE.
35  *
36  *	from: @(#)DEFS.h	5.1 (Berkeley) 4/23/90
37  *	$Id: asm.h,v 1.1 1997/03/09 10:39:15 bde Exp $
38  */
39 
40 #include <sys/cdefs.h>
41 
42 #ifdef PIC
43 #define	PIC_PROLOGUE	\
44 	pushl	%ebx;	\
45 	call	1f;	\
46 1:			\
47 	popl	%ebx;	\
48 	addl	$_GLOBAL_OFFSET_TABLE_+[.-1b],%ebx
49 #define	PIC_EPILOGUE	\
50 	popl	%ebx
51 #define	PIC_PLT(x)	x@PLT
52 #define	PIC_GOT(x)	x@GOT(%ebx)
53 #define	PIC_GOTOFF(x)	x@GOTOFF(%ebx)
54 #else
55 #define	PIC_PROLOGUE
56 #define	PIC_EPILOGUE
57 #define	PIC_PLT(x)	x
58 #define	PIC_GOT(x)	x
59 #define	PIC_GOTOFF(x)	x
60 #endif
61 
62 /*
63  * CNAME and HIDENAME manage the relationship between symbol names in C
64  * and the equivalent assembly language names.  CNAME is given a name as
65  * it would be used in a C program.  It expands to the equivalent assembly
66  * language name.  HIDENAME is given an assembly-language name, and expands
67  * to a possibly-modified form that will be invisible to C programs.
68  */
69 #if defined(__ELF__) /* { */
70 #define CNAME(csym)		csym
71 #define HIDENAME(asmsym)	__CONCAT(.,asmsym)
72 #else /* } { */
73 #define CNAME(csym)		__CONCAT(_,csym)
74 #define HIDENAME(asmsym)	asmsym
75 #endif /* } */
76 
77 
78 /* XXX should use align 4,0x90 for -m486. */
79 #define _START_ENTRY	.text; .align 2,0x90;
80 #if 0
81 /* Data is not used, except perhaps by non-g prof, which we don't support. */
82 #define _MID_ENTRY	.data; .align 2; 8:; .long 0;		\
83 			.text; lea 8b,%eax;
84 #else
85 #define _MID_ENTRY
86 #endif
87 
88 #ifdef PROF
89 
90 #define ALTENTRY(x)	_START_ENTRY	\
91 			.globl CNAME(x); .type CNAME(x),@function; CNAME(x):; \
92 			_MID_ENTRY	\
93 			call HIDENAME(mcount); jmp 9f
94 
95 #define ENTRY(x)	_START_ENTRY	\
96 			.globl CNAME(x); .type CNAME(x),@function; CNAME(x):; \
97 			_MID_ENTRY	\
98 			call HIDENAME(mcount); 9:
99 
100 
101 #define	ALTASENTRY(x)	_START_ENTRY	\
102 			.globl x; .type x,@function; x:;	\
103 			_MID_ENTRY	\
104 			call HIDENAME(mcount); jmp 9f
105 
106 #define	ASENTRY(x)	_START_ENTRY	\
107 			.globl x; .type x,@function; x:;	\
108 			_MID_ENTRY	\
109 			call HIDENAME(mcount); 9:
110 
111 #else	/* !PROF */
112 
113 #define	ENTRY(x)	_START_ENTRY .globl CNAME(x); .type CNAME(x),@function; \
114 			CNAME(x):
115 #define	ALTENTRY(x)	ENTRY(x)
116 
117 #define	ASENTRY(x)	_START_ENTRY .globl x; .type x,@function; x:
118 #define	ALTASENTRY(x)	ASENTRY(x)
119 
120 #endif
121 
122 /*
123  * This header is currently only used in lib/msun/i387.
124  * Use it to generate code to select between the generic math functions
125  * and the i387 ones.
126  */
127 #undef ENTRY
128 #define	ANAME(x)	CNAME(__CONCAT(__i387_,x))
129 #define	ASELNAME(x)	CNAME(__CONCAT(__arch_select_,x))
130 #define	AVECNAME(x)	CNAME(__CONCAT(__arch_,x))
131 #define	GNAME(x)	CNAME(__CONCAT(__generic_,x))
132 
133 /* Don't bother profiling this. */
134 #ifdef PIC
135 #define	ARCH_DISPATCH(x) \
136 			_START_ENTRY; \
137 			.globl CNAME(x); .type CNAME(x),@function; CNAME(x): ; \
138 			PIC_PROLOGUE; \
139 			movl PIC_GOT(AVECNAME(x)),%eax; \
140 			PIC_EPILOGUE; \
141 			jmpl *(%eax)
142 
143 #define	ARCH_SELECT(x)	_START_ENTRY; \
144 			.type ASELNAME(x),@function; \
145 			ASELNAME(x): \
146 			PIC_PROLOGUE; \
147 			call PIC_PLT(CNAME(__get_hw_float)); \
148 			testl %eax,%eax; \
149 			movl PIC_GOT(ANAME(x)),%eax; \
150 			jne 8f; \
151 			movl PIC_GOT(GNAME(x)),%eax; \
152 			8: \
153 			movl PIC_GOT(AVECNAME(x)),%edx; \
154 			movl %eax,(%edx); \
155 			PIC_EPILOGUE; \
156 			jmpl *%eax
157 #else /* !PIC */
158 #define	ARCH_DISPATCH(x) \
159 			_START_ENTRY; \
160 			.globl CNAME(x); .type CNAME(x),@function; CNAME(x): ; \
161 			jmpl *AVECNAME(x)
162 
163 #define	ARCH_SELECT(x)	_START_ENTRY; \
164 			.type ASELNAME(x),@function; \
165 			ASELNAME(x): \
166 			call CNAME(__get_hw_float); \
167 			testl %eax,%eax; \
168 			movl $ANAME(x),%eax; \
169 			jne 8f; \
170 			movl $GNAME(x),%eax; \
171 			8: \
172 			movl %eax,AVECNAME(x); \
173 			jmpl *%eax
174 #endif /* PIC */
175 
176 #define	ARCH_VECTOR(x)	.data; .align 2; \
177 			.globl AVECNAME(x); \
178 			.type AVECNAME(x),@object; \
179 			.size AVECNAME(x),4; \
180 			AVECNAME(x): .long ASELNAME(x)
181 
182 #ifdef PROF
183 
184 #define	ALTENTRY(x)	ENTRY(x); jmp 9f
185 #define	ENTRY(x)	ARCH_VECTOR(x); ARCH_SELECT(x); ARCH_DISPATCH(x); \
186 			_START_ENTRY; \
187 			.globl ANAME(x); .type ANAME(x),@function; ANAME(x):; \
188 			call HIDENAME(mcount); 9:
189 
190 #else /* !PROF */
191 
192 #define	ALTENTRY(x)	ENTRY(x)
193 #define	ENTRY(x)	ARCH_VECTOR(x); ARCH_SELECT(x); ARCH_DISPATCH(x); \
194 			_START_ENTRY; \
195 			.globl ANAME(x); .type ANAME(x),@function; ANAME(x):
196 
197 #endif /* PROF */
198 
199 #ifndef RCSID
200 #define RCSID(a)
201 #endif
202