1/* Traditional frame unwind support, for GDB the GNU Debugger.
2
3   Copyright 2003 Free Software Foundation, Inc.
4
5   This file is part of GDB.
6
7   This program is free software; you can redistribute it and/or modify
8   it under the terms of the GNU General Public License as published by
9   the Free Software Foundation; either version 2 of the License, or
10   (at your option) any later version.
11
12   This program is distributed in the hope that it will be useful,
13   but WITHOUT ANY WARRANTY; without even the implied warranty of
14   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15   GNU General Public License for more details.
16
17   You should have received a copy of the GNU General Public License
18   along with this program; if not, write to the Free Software
19   Foundation, Inc., 59 Temple Place - Suite 330,
20   Boston, MA 02111-1307, USA.  */
21
22#ifndef TRAD_FRAME_H
23#define TRAD_FRAME_H
24
25struct frame_info;
26
27/* A traditional saved regs table, indexed by REGNUM, encoding where
28   the value of REGNUM for the previous frame can be found in this
29   frame.
30
31   The table is initialized with an identity encoding (ADDR == -1,
32   REALREG == REGNUM) indicating that the value of REGNUM in the
33   previous frame can be found in register REGNUM (== REALREG) in this
34   frame.
35
36   The initial encoding can then be changed:
37
38   Modify ADDR (REALREG >= 0, ADDR != -1) to indicate that the value
39   of register REGNUM in the previous frame can be found in memory at
40   ADDR in this frame (addr_p, !realreg_p, !value_p).
41
42   Modify REALREG (REALREG >= 0, ADDR == -1) to indicate that the
43   value of register REGNUM in the previous frame is found in register
44   REALREG in this frame (!addr_p, realreg_p, !value_p).
45
46   Call trad_frame_set_value (REALREG == -1) to indicate that the
47   value of register REGNUM in the previous frame is found in ADDR
48   (!addr_p, !realreg_p, value_p).
49
50   Call trad_frame_set_unknown (REALREG == -2) to indicate that the
51   register's value is not known.  */
52
53struct trad_frame_saved_reg
54{
55  LONGEST addr; /* A CORE_ADDR fits in a longest.  */
56  int realreg;
57};
58
59/* Encode REGNUM value in the trad-frame.  */
60void trad_frame_set_value (struct trad_frame_saved_reg this_saved_regs[],
61			   int regnum, LONGEST val);
62
63/* Mark REGNUM as unknown.  */
64void trad_frame_set_unknown (struct trad_frame_saved_reg this_saved_regs[],
65			     int regnum);
66
67/* Convenience functions, return non-zero if the register has been
68   encoded as specified.  */
69int trad_frame_value_p (struct trad_frame_saved_reg this_saved_regs[],
70			int regnum);
71int trad_frame_addr_p (struct trad_frame_saved_reg this_saved_regs[],
72		       int regnum);
73int trad_frame_realreg_p (struct trad_frame_saved_reg this_saved_regs[],
74			  int regnum);
75
76
77/* Return a freshly allocated (and initialized) trad_frame array.  */
78struct trad_frame_saved_reg *trad_frame_alloc_saved_regs (struct frame_info *next_frame);
79
80/* Given the trad_frame info, return the location of the specified
81   register.  */
82void trad_frame_prev_register (struct frame_info *next_frame,
83			       struct trad_frame_saved_reg this_saved_regs[],
84			       int regnum, int *optimizedp,
85			       enum lval_type *lvalp, CORE_ADDR *addrp,
86			       int *realregp, void *bufferp);
87
88#endif
89