trad-frame.h revision 1.7 
1/* Traditional frame unwind support, for GDB the GNU Debugger.
2
3   Copyright (C) 2003-2017 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 3 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, see <http://www.gnu.org/licenses/>.  */
19
20#ifndef TRAD_FRAME_H
21#define TRAD_FRAME_H
22
23#include "frame.h"		/* For "struct frame_id".  */
24
25struct frame_info;
26struct trad_frame_cache;
27
28/* A simple, or traditional frame cache.
29
30   The entire cache is populated in a single pass and then generic
31   routines are used to extract the various cache values.  */
32
33struct trad_frame_cache *trad_frame_cache_zalloc (struct frame_info *);
34
35/* This frame's ID.  */
36void trad_frame_set_id (struct trad_frame_cache *this_trad_cache,
37			struct frame_id this_id);
38void trad_frame_get_id (struct trad_frame_cache *this_trad_cache,
39			struct frame_id *this_id);
40void trad_frame_set_this_base (struct trad_frame_cache *this_trad_cache,
41			       CORE_ADDR this_base);
42CORE_ADDR trad_frame_get_this_base (struct trad_frame_cache *this_trad_cache);
43
44void trad_frame_set_reg_realreg (struct trad_frame_cache *this_trad_cache,
45				 int regnum, int realreg);
46void trad_frame_set_reg_addr (struct trad_frame_cache *this_trad_cache,
47			      int regnum, CORE_ADDR addr);
48void trad_frame_set_reg_value (struct trad_frame_cache *this_cache,
49			       int regnum, LONGEST val);
50
51struct value *trad_frame_get_register (struct trad_frame_cache *this_trad_cache,
52				       struct frame_info *this_frame,
53				       int regnum);
54
55/* A traditional saved regs table, indexed by REGNUM, encoding where
56   the value of REGNUM for the previous frame can be found in this
57   frame.
58
59   The table is initialized with an identity encoding (ADDR == -1,
60   REALREG == REGNUM) indicating that the value of REGNUM in the
61   previous frame can be found in register REGNUM (== REALREG) in this
62   frame.
63
64   The initial encoding can then be changed:
65
66   Modify ADDR (REALREG >= 0, ADDR != -1) to indicate that the value
67   of register REGNUM in the previous frame can be found in memory at
68   ADDR in this frame (addr_p, !realreg_p, !value_p).
69
70   Modify REALREG (REALREG >= 0, ADDR == -1) to indicate that the
71   value of register REGNUM in the previous frame is found in register
72   REALREG in this frame (!addr_p, realreg_p, !value_p).
73
74   Call trad_frame_set_value (REALREG == -1) to indicate that the
75   value of register REGNUM in the previous frame is found in ADDR
76   (!addr_p, !realreg_p, value_p).
77
78   Call trad_frame_set_unknown (REALREG == -2) to indicate that the
79   register's value is not known.  */
80
81struct trad_frame_saved_reg
82{
83  LONGEST addr; /* A CORE_ADDR fits in a longest.  */
84  int realreg;
85};
86
87/* Encode REGNUM value in the trad-frame.  */
88void trad_frame_set_value (struct trad_frame_saved_reg this_saved_regs[],
89			   int regnum, LONGEST val);
90
91/* Mark REGNUM as unknown.  */
92void trad_frame_set_unknown (struct trad_frame_saved_reg this_saved_regs[],
93			     int regnum);
94
95/* Convenience functions, return non-zero if the register has been
96   encoded as specified.  */
97int trad_frame_value_p (struct trad_frame_saved_reg this_saved_regs[],
98			int regnum);
99int trad_frame_addr_p (struct trad_frame_saved_reg this_saved_regs[],
100		       int regnum);
101int trad_frame_realreg_p (struct trad_frame_saved_reg this_saved_regs[],
102			  int regnum);
103
104
105/* Return a freshly allocated (and initialized) trad_frame array.  */
106struct trad_frame_saved_reg *trad_frame_alloc_saved_regs (struct frame_info *);
107struct trad_frame_saved_reg *trad_frame_alloc_saved_regs (struct gdbarch *);
108
109/* Given the trad_frame info, return the location of the specified
110   register.  */
111struct value *trad_frame_get_prev_register (struct frame_info *this_frame,
112					    struct trad_frame_saved_reg this_saved_regs[],
113					    int regnum);
114
115#endif
116