xref: /freebsd/sys/i386/include/db_machdep.h (revision 6b3455a7665208c366849f0b2b3bc916fb97516e)
1 /*
2  * Mach Operating System
3  * Copyright (c) 1991,1990 Carnegie Mellon University
4  * All Rights Reserved.
5  *
6  * Permission to use, copy, modify and distribute this software and its
7  * documentation is hereby granted, provided that both the copyright
8  * notice and this permission notice appear in all copies of the
9  * software, derivative works or modified versions, and any portions
10  * thereof, and that both notices appear in supporting documentation.
11  *
12  * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
13  * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
14  * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
15  *
16  * Carnegie Mellon requests users of this software to return to
17  *
18  *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
19  *  School of Computer Science
20  *  Carnegie Mellon University
21  *  Pittsburgh PA 15213-3890
22  *
23  * any improvements or extensions that they make and grant Carnegie Mellon
24  * the rights to redistribute these changes.
25  *
26  * $FreeBSD$
27  */
28 
29 #ifndef _MACHINE_DB_MACHDEP_H_
30 #define	_MACHINE_DB_MACHDEP_H_
31 
32 #include <machine/frame.h>
33 #include <machine/trap.h>
34 
35 typedef	vm_offset_t	db_addr_t;	/* address - unsigned */
36 typedef	int		db_expr_t;	/* expression - signed */
37 
38 #define	PC_REGS()	((db_addr_t)kdb_thrctx->pcb_eip)
39 
40 #define	BKPT_INST	0xcc		/* breakpoint instruction */
41 #define	BKPT_SIZE	(1)		/* size of breakpoint inst */
42 #define	BKPT_SET(inst)	(BKPT_INST)
43 
44 #define BKPT_SKIP		kdb_frame->tf_eip += 1
45 
46 #define	FIXUP_PC_AFTER_BREAK	kdb_frame->tf_eip -= 1;
47 
48 #define	db_clear_single_step	kdb_cpu_clear_singlestep
49 #define	db_set_single_step	kdb_cpu_set_singlestep
50 
51 #define	IS_BREAKPOINT_TRAP(type, code)	((type) == T_BPTFLT)
52 /*
53  * Watchpoints are not supported.  The debug exception type is in %dr6
54  * and not yet in the args to this macro.
55  */
56 #define IS_WATCHPOINT_TRAP(type, code)	0
57 
58 #define	I_CALL		0xe8
59 #define	I_CALLI		0xff
60 #define	I_RET		0xc3
61 #define	I_IRET		0xcf
62 
63 #define	inst_trap_return(ins)	(((ins)&0xff) == I_IRET)
64 #define	inst_return(ins)	(((ins)&0xff) == I_RET)
65 #define	inst_call(ins)		(((ins)&0xff) == I_CALL || \
66 				 (((ins)&0xff) == I_CALLI && \
67 				  ((ins)&0x3800) == 0x1000))
68 #define inst_load(ins)		0
69 #define inst_store(ins)		0
70 
71 /*
72  * There no interesting addresses below _kstack = 0xefbfe000.  There
73  * are small absolute values for GUPROF, but we don't want to see them.
74  * Treat "negative" addresses below _kstack as non-small to allow for
75  * future reductions of _kstack and to avoid sign extension problems.
76  *
77  * There is one interesting symbol above -db_maxoff = 0xffff0000,
78  * namely _APTD = 0xfffff000.  Accepting this would mess up the
79  * printing of small negative offsets.  The next largest symbol is
80  * _APTmap = 0xffc00000.  Accepting this is OK (unless db_maxoff is
81  * set to >= 0x400000 - (max stack offset)).
82  */
83 #define	DB_SMALL_VALUE_MAX	0x7fffffff
84 #define	DB_SMALL_VALUE_MIN	(-0x400001)
85 
86 #endif /* !_MACHINE_DB_MACHDEP_H_ */
87