xref: /freebsd/sys/i386/include/profile.h (revision cb7aa33ac6cd46a5434798e50363136e64f3ae98)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1992, 1993
5  *	The Regents of the University of California.  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  * 3. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  *
31  *	@(#)profile.h	8.1 (Berkeley) 6/11/93
32  * $FreeBSD$
33  */
34 
35 #ifndef _MACHINE_PROFILE_H_
36 #define	_MACHINE_PROFILE_H_
37 
38 #ifndef _KERNEL
39 
40 #include <sys/cdefs.h>
41 
42 #define	FUNCTION_ALIGNMENT	4
43 
44 #define	_MCOUNT_DECL static __inline void _mcount
45 
46 #define	MCOUNT								\
47 void									\
48 mcount()								\
49 {									\
50 	uintfptr_t selfpc, frompc, ecx;					\
51 	/*								\
52 	 * In gcc 4.2, ecx might be used in the caller as the arg	\
53 	 * pointer if the stack realignment option is set (-mstackrealign) \
54 	 * or if the caller has the force_align_arg_pointer attribute	\
55 	 * (stack realignment is ALWAYS on for main).  Preserve ecx	\
56 	 * here.							\
57 	 */								\
58 	__asm("" : "=c" (ecx));						\
59 	/*								\
60 	 * Find the return address for mcount,				\
61 	 * and the return address for mcount's caller.			\
62 	 *								\
63 	 * selfpc = pc pushed by call to mcount				\
64 	 */								\
65 	__asm("movl 4(%%ebp),%0" : "=r" (selfpc));			\
66 	/*								\
67 	 * frompc = pc pushed by call to mcount's caller.		\
68 	 * The caller's stack frame has already been built, so %ebp is	\
69 	 * the caller's frame pointer.  The caller's raddr is in the	\
70 	 * caller's frame following the caller's caller's frame pointer.\
71 	 */								\
72 	__asm("movl (%%ebp),%0" : "=r" (frompc));			\
73 	frompc = ((uintfptr_t *)frompc)[1];				\
74 	_mcount(frompc, selfpc);					\
75 	__asm("" : : "c" (ecx));					\
76 }
77 
78 typedef	u_int	uintfptr_t;
79 
80 /*
81  * An unsigned integral type that can hold non-negative difference between
82  * function pointers.
83  */
84 typedef	u_int	fptrdiff_t;
85 
86 __BEGIN_DECLS
87 void	mcount(void) __asm(".mcount");
88 __END_DECLS
89 
90 #endif /* !_KERNEL */
91 
92 #endif /* !_MACHINE_PROFILE_H_ */
93