xref: /freebsd/sys/amd64/include/asm.h (revision c697fb7f)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1990 The Regents of the University of California.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to Berkeley by
8  * William Jolitz.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. Neither the name of the University nor the names of its contributors
19  *    may be used to endorse or promote products derived from this software
20  *    without specific prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  *
34  *	from: @(#)DEFS.h	5.1 (Berkeley) 4/23/90
35  * $FreeBSD$
36  */
37 
38 #ifndef _MACHINE_ASM_H_
39 #define	_MACHINE_ASM_H_
40 
41 #include <sys/cdefs.h>
42 
43 #ifdef PIC
44 #define	PIC_PLT(x)	x@PLT
45 #define	PIC_GOT(x)	x@GOTPCREL(%rip)
46 #else
47 #define	PIC_PLT(x)	x
48 #endif
49 
50 /*
51  * CNAME and HIDENAME manage the relationship between symbol names in C
52  * and the equivalent assembly language names.  CNAME is given a name as
53  * it would be used in a C program.  It expands to the equivalent assembly
54  * language name.  HIDENAME is given an assembly-language name, and expands
55  * to a possibly-modified form that will be invisible to C programs.
56  */
57 #define CNAME(csym)		csym
58 #define HIDENAME(asmsym)	.asmsym
59 
60 #define _START_ENTRY	.text; .p2align 4,0x90
61 
62 #define _ENTRY(x)	_START_ENTRY; \
63 			.globl CNAME(x); .type CNAME(x),@function; CNAME(x):; \
64 			.cfi_startproc
65 
66 #ifdef PROF
67 #define	ALTENTRY(x)	_ENTRY(x); \
68 			pushq %rbp; \
69 			.cfi_def_cfa_offset 16; \
70 			.cfi_offset %rbp, -16; \
71 			movq %rsp,%rbp; \
72 			call PIC_PLT(HIDENAME(mcount)); \
73 			popq %rbp; \
74 			.cfi_restore %rbp; \
75 			.cfi_def_cfa_offset 8; \
76 			jmp 9f
77 #define	ENTRY(x)	_ENTRY(x); \
78 			pushq %rbp; \
79 			.cfi_def_cfa_offset 16; \
80 			.cfi_offset %rbp, -16; \
81 			movq %rsp,%rbp; \
82 			call PIC_PLT(HIDENAME(mcount)); \
83 			popq %rbp; \
84 			.cfi_restore %rbp; \
85 			.cfi_def_cfa_offset 8; \
86 			9:
87 #else
88 #define	ALTENTRY(x)	_ENTRY(x)
89 #define	ENTRY(x)	_ENTRY(x)
90 #endif
91 
92 #define	END(x)		.size x, . - x; .cfi_endproc
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 #define	WEAK_REFERENCE(sym, alias)					\
100 	.weak CNAME(alias);						\
101 	.equ CNAME(alias),CNAME(sym)
102 
103 #define RCSID(x)	.text; .asciz x
104 
105 #undef __FBSDID
106 #if !defined(STRIP_FBSDID)
107 #define __FBSDID(s)	.ident s
108 #else
109 #define __FBSDID(s)	/* nothing */
110 #endif /* !STRIP_FBSDID */
111 
112 #endif /* !_MACHINE_ASM_H_ */
113