aboutsummaryrefslogtreecommitdiff
path: root/gdb/trad-frame.h
blob: 0351441dd3690b44a2da65d04f6d9fed6543fc3b (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
/* Traditional frame unwind support, for GDB the GNU Debugger.

   Copyright (C) 2003-2021 Free Software Foundation, Inc.

   This file is part of GDB.

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 3 of the License, or
   (at your option) any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */

#ifndef TRAD_FRAME_H
#define TRAD_FRAME_H

#include "frame.h"		/* For "struct frame_id".  */

struct frame_info;
struct regcache_map_entry;
struct trad_frame_cache;

/* A simple, or traditional frame cache.

   The entire cache is populated in a single pass and then generic
   routines are used to extract the various cache values.  */

struct trad_frame_cache *trad_frame_cache_zalloc (struct frame_info *);

/* This frame's ID.  */
void trad_frame_set_id (struct trad_frame_cache *this_trad_cache,
			struct frame_id this_id);
void trad_frame_get_id (struct trad_frame_cache *this_trad_cache,
			struct frame_id *this_id);
void trad_frame_set_this_base (struct trad_frame_cache *this_trad_cache,
			       CORE_ADDR this_base);
CORE_ADDR trad_frame_get_this_base (struct trad_frame_cache *this_trad_cache);

void trad_frame_set_reg_realreg (struct trad_frame_cache *this_trad_cache,
				 int regnum, int realreg);
void trad_frame_set_reg_addr (struct trad_frame_cache *this_trad_cache,
			      int regnum, CORE_ADDR addr);
void trad_frame_set_reg_regmap (struct trad_frame_cache *this_trad_cache,
				const struct regcache_map_entry *regmap,
				CORE_ADDR addr, size_t size);
void trad_frame_set_reg_value (struct trad_frame_cache *this_cache,
			       int regnum, LONGEST val);

/* Given the cache in THIS_TRAD_CACHE, set the value of REGNUM to the bytes
   contained in BYTES with size SIZE.  */
void trad_frame_set_reg_value_bytes (struct trad_frame_cache *this_trad_cache,
				     int regnum,
				     gdb::array_view<const gdb_byte> bytes);

struct value *trad_frame_get_register (struct trad_frame_cache *this_trad_cache,
				       struct frame_info *this_frame,
				       int regnum);

/* Describes the kind of encoding a stored register has.  */
enum class trad_frame_saved_reg_kind
{
  /* Register value is unknown.  */
  UNKNOWN = 0,
  /* Register value is a constant.  */
  VALUE,
  /* Register value is in another register.  */
  REALREG,
  /* Register value is at an address.  */
  ADDR,
  /* Register value is a sequence of bytes.  */
  VALUE_BYTES
};

/* A struct that describes a saved register in a frame.  */

struct trad_frame_saved_reg
{
  /* Setters */

  /* Encode that the saved register's value is constant VAL in the
     trad-frame.  */
  void set_value (LONGEST val)
  {
    m_kind = trad_frame_saved_reg_kind::VALUE;
    m_reg.value = val;
  }

  /* Encode that the saved register's value is stored in register REALREG.  */
  void set_realreg (int realreg)
  {
    m_kind = trad_frame_saved_reg_kind::REALREG;
    m_reg.realreg = realreg;
  }

  /* Encode that the saved register's value is stored in memory at ADDR.  */
  void set_addr (LONGEST addr)
  {
    m_kind = trad_frame_saved_reg_kind::ADDR;
    m_reg.addr = addr;
  }

  /* Encode that the saved register's value is unknown.  */
  void set_unknown ()
  {
    m_kind = trad_frame_saved_reg_kind::UNKNOWN;
  }

  /* Encode that the saved register's value is stored as a sequence of bytes.
     This is useful when the value is larger than what primitive types
     can hold.  */
  void set_value_bytes (gdb::array_view<const gdb_byte> bytes)
  {
    /* Allocate the space and copy the data bytes.  */
    gdb_byte *data = FRAME_OBSTACK_CALLOC (bytes.size (), gdb_byte);
    memcpy (data, bytes.data (), bytes.size ());

    m_kind = trad_frame_saved_reg_kind::VALUE_BYTES;
    m_reg.value_bytes = data;
  }

  /* Getters */

  LONGEST value () const
  {
    gdb_assert (m_kind == trad_frame_saved_reg_kind::VALUE);
    return m_reg.value;
  }

  int realreg () const
  {
    gdb_assert (m_kind == trad_frame_saved_reg_kind::REALREG);
    return m_reg.realreg;
  }

  LONGEST addr () const
  {
    gdb_assert (m_kind == trad_frame_saved_reg_kind::ADDR);
    return m_reg.addr;
  }

  const gdb_byte *value_bytes () const
  {
    gdb_assert (m_kind == trad_frame_saved_reg_kind::VALUE_BYTES);
    return m_reg.value_bytes;
  }

  /* Convenience functions, return true if the register has been
     encoded as specified.  Return false otherwise.  */
  bool is_value () const
  {
    return m_kind == trad_frame_saved_reg_kind::VALUE;
  }

  bool is_realreg () const
  {
    return m_kind == trad_frame_saved_reg_kind::REALREG;
  }

  bool is_addr () const
  {
    return m_kind == trad_frame_saved_reg_kind::ADDR;
  }

  bool is_unknown () const
  {
    return m_kind == trad_frame_saved_reg_kind::UNKNOWN;
  }

  bool is_value_bytes () const
  {
    return m_kind == trad_frame_saved_reg_kind::VALUE_BYTES;
  }

private:

  trad_frame_saved_reg_kind m_kind;

  union {
    LONGEST value;
    int realreg;
    LONGEST addr;
    const gdb_byte *value_bytes;
  } m_reg;
};

/* Reset the saved regs cache, setting register values to REALREG.  */
void trad_frame_reset_saved_regs (struct gdbarch *gdbarch,
				  trad_frame_saved_reg *regs);

/* Return a freshly allocated (and initialized) trad_frame array.  */
trad_frame_saved_reg *trad_frame_alloc_saved_regs (struct frame_info *);
trad_frame_saved_reg *trad_frame_alloc_saved_regs (struct gdbarch *);

/* Given the trad_frame info, return the location of the specified
   register.  */
struct value *trad_frame_get_prev_register (struct frame_info *this_frame,
					    trad_frame_saved_reg this_saved_regs[],
					    int regnum);

#endif