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/tmp/gdb-7.10/gdb/user-regs.c
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1 /* User visible, per-frame registers, for GDB, the GNU debugger.
2 
3  Copyright (C) 2002-2015 Free Software Foundation, Inc.
4 
5  Contributed by Red Hat.
6 
7  This file is part of GDB.
8 
9  This program is free software; you can redistribute it and/or modify
10  it under the terms of the GNU General Public License as published by
11  the Free Software Foundation; either version 3 of the License, or
12  (at your option) any later version.
13 
14  This program is distributed in the hope that it will be useful,
15  but WITHOUT ANY WARRANTY; without even the implied warranty of
16  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17  GNU General Public License for more details.
18 
19  You should have received a copy of the GNU General Public License
20  along with this program. If not, see <http://www.gnu.org/licenses/>. */
21 
22 #include "defs.h"
23 #include "user-regs.h"
24 #include "gdbtypes.h"
25 #include "frame.h"
26 #include "arch-utils.h"
27 #include "command.h"
28 #include "cli/cli-cmds.h"
29 
30 /* A table of user registers.
31 
32  User registers have regnum's that live above of the range [0
33  .. gdbarch_num_regs + gdbarch_num_pseudo_regs)
34  (which is controlled by the target).
35  The target should never see a user register's regnum value.
36 
37  Always append, never delete. By doing this, the relative regnum
38  (offset from gdbarch_num_regs + gdbarch_num_pseudo_regs)
39  assigned to each user register never changes. */
40 
41 struct user_reg
42 {
43  const char *name;
44  struct value *(*read) (struct frame_info * frame, const void *baton);
45  const void *baton;
46  struct user_reg *next;
47 };
48 
49 /* This structure is named gdb_user_regs instead of user_regs to avoid
50  conflicts with any "struct user_regs" in system headers. For instance,
51  on ARM GNU/Linux native builds, nm-linux.h includes <signal.h> includes
52  <sys/ucontext.h> includes <sys/procfs.h> includes <sys/user.h>, which
53  declares "struct user_regs". */
54 
56 {
57  struct user_reg *first;
58  struct user_reg **last;
59 };
60 
61 static void
62 append_user_reg (struct gdb_user_regs *regs, const char *name,
63  user_reg_read_ftype *read, const void *baton,
64  struct user_reg *reg)
65 {
66  /* The caller is responsible for allocating memory needed to store
67  the register. By doing this, the function can operate on a
68  register list stored in the common heap or a specific obstack. */
69  gdb_assert (reg != NULL);
70  reg->name = name;
71  reg->read = read;
72  reg->baton = baton;
73  reg->next = NULL;
74  (*regs->last) = reg;
75  regs->last = &(*regs->last)->next;
76 }
77 
78 /* An array of the builtin user registers. */
79 
80 static struct gdb_user_regs builtin_user_regs = {
81  NULL, &builtin_user_regs.first
82 };
83 
84 void
86  const void *baton)
87 {
88  append_user_reg (&builtin_user_regs, name, read, baton,
89  XNEW (struct user_reg));
90 }
91 
92 /* Per-architecture user registers. Start with the builtin user
93  registers and then, again, append. */
94 
96 
97 static void *
99 {
100  struct user_reg *reg;
101  struct gdb_user_regs *regs
102  = GDBARCH_OBSTACK_ZALLOC (gdbarch, struct gdb_user_regs);
103 
104  regs->last = &regs->first;
105  for (reg = builtin_user_regs.first; reg != NULL; reg = reg->next)
106  append_user_reg (regs, reg->name, reg->read, reg->baton,
107  GDBARCH_OBSTACK_ZALLOC (gdbarch, struct user_reg));
108  return regs;
109 }
110 
111 void
112 user_reg_add (struct gdbarch *gdbarch, const char *name,
113  user_reg_read_ftype *read, const void *baton)
114 {
115  struct gdb_user_regs *regs = gdbarch_data (gdbarch, user_regs_data);
116 
117  if (regs == NULL)
118  {
119  /* ULGH, called during architecture initialization. Patch
120  things up. */
121  regs = user_regs_init (gdbarch);
122  deprecated_set_gdbarch_data (gdbarch, user_regs_data, regs);
123  }
124  append_user_reg (regs, name, read, baton,
125  GDBARCH_OBSTACK_ZALLOC (gdbarch, struct user_reg));
126 }
127 
128 int
130  int len)
131 {
132  /* Make life easy, set the len to something reasonable. */
133  if (len < 0)
134  len = strlen (name);
135 
136  /* Search register name space first - always let an architecture
137  specific register override the user registers. */
138  {
139  int i;
140  int maxregs = (gdbarch_num_regs (gdbarch)
141  + gdbarch_num_pseudo_regs (gdbarch));
142 
143  for (i = 0; i < maxregs; i++)
144  {
145  const char *regname = gdbarch_register_name (gdbarch, i);
146 
147  if (regname != NULL && len == strlen (regname)
148  && strncmp (regname, name, len) == 0)
149  {
150  return i;
151  }
152  }
153  }
154 
155  /* Search the user name space. */
156  {
157  struct gdb_user_regs *regs = gdbarch_data (gdbarch, user_regs_data);
158  struct user_reg *reg;
159  int nr;
160 
161  for (nr = 0, reg = regs->first; reg != NULL; reg = reg->next, nr++)
162  {
163  if ((len < 0 && strcmp (reg->name, name))
164  || (len == strlen (reg->name)
165  && strncmp (reg->name, name, len) == 0))
166  return gdbarch_num_regs (gdbarch)
167  + gdbarch_num_pseudo_regs (gdbarch) + nr;
168  }
169  }
170 
171  return -1;
172 }
173 
174 static struct user_reg *
175 usernum_to_user_reg (struct gdbarch *gdbarch, int usernum)
176 {
177  struct gdb_user_regs *regs = gdbarch_data (gdbarch, user_regs_data);
178  struct user_reg *reg;
179 
180  for (reg = regs->first; reg != NULL; reg = reg->next)
181  {
182  if (usernum == 0)
183  return reg;
184  usernum--;
185  }
186  return NULL;
187 }
188 
189 const char *
191 {
192  int maxregs = (gdbarch_num_regs (gdbarch)
193  + gdbarch_num_pseudo_regs (gdbarch));
194 
195  if (regnum < 0)
196  return NULL;
197  else if (regnum < maxregs)
198  return gdbarch_register_name (gdbarch, regnum);
199  else
200  {
201  struct user_reg *reg = usernum_to_user_reg (gdbarch, regnum - maxregs);
202  if (reg == NULL)
203  return NULL;
204  else
205  return reg->name;
206  }
207 }
208 
209 struct value *
210 value_of_user_reg (int regnum, struct frame_info *frame)
211 {
212  struct gdbarch *gdbarch = get_frame_arch (frame);
213  int maxregs = (gdbarch_num_regs (gdbarch)
214  + gdbarch_num_pseudo_regs (gdbarch));
215  struct user_reg *reg = usernum_to_user_reg (gdbarch, regnum - maxregs);
216 
217  gdb_assert (reg != NULL);
218  return reg->read (frame, reg->baton);
219 }
220 
221 static void
222 maintenance_print_user_registers (char *args, int from_tty)
223 {
224  struct gdbarch *gdbarch = get_current_arch ();
225  struct gdb_user_regs *regs;
226  struct user_reg *reg;
227  int regnum;
228 
229  regs = gdbarch_data (gdbarch, user_regs_data);
230  regnum = gdbarch_num_regs (gdbarch) + gdbarch_num_pseudo_regs (gdbarch);
231 
232  fprintf_unfiltered (gdb_stdout, " %-11s %3s\n", "Name", "Nr");
233  for (reg = regs->first; reg != NULL; reg = reg->next, ++regnum)
234  fprintf_unfiltered (gdb_stdout, " %-11s %3d\n", reg->name, regnum);
235 }
236 
237 extern initialize_file_ftype _initialize_user_regs; /* -Wmissing-prototypes */
238 
239 void
241 {
243 
244  add_cmd ("user-registers", class_maintenance,
246  _("List the names of the current user registers.\n"),
248 }
const char * user_reg_map_regnum_to_name(struct gdbarch *gdbarch, int regnum)
Definition: user-regs.c:190
ssize_t read(int fd, void *buf, size_t count)
Definition: expect-read1.c:26
struct user_reg * next
Definition: user-regs.c:46
void * gdbarch_data(struct gdbarch *gdbarch, struct gdbarch_data *data)
Definition: gdbarch.c:4845
struct ui_file * gdb_stdout
Definition: main.c:71
struct value *(* read)(struct frame_info *frame, const void *baton)
Definition: user-regs.c:44
static void append_user_reg(struct gdb_user_regs *regs, const char *name, user_reg_read_ftype *read, const void *baton, struct user_reg *reg)
Definition: user-regs.c:62
int gdbarch_num_regs(struct gdbarch *gdbarch)
Definition: gdbarch.c:1898
#define _(String)
Definition: gdb_locale.h:40
#define GDBARCH_OBSTACK_ZALLOC(GDBARCH, TYPE)
Definition: gdbarch.h:1615
initialize_file_ftype _initialize_user_regs
const void * baton
Definition: user-regs.c:45
int gdbarch_num_pseudo_regs(struct gdbarch *gdbarch)
Definition: gdbarch.c:1916
const char *const name
Definition: aarch64-tdep.c:68
static struct user_reg * usernum_to_user_reg(struct gdbarch *gdbarch, int usernum)
Definition: user-regs.c:175
void initialize_file_ftype(void)
Definition: defs.h:281
static void * user_regs_init(struct gdbarch *gdbarch)
Definition: user-regs.c:98
void fprintf_unfiltered(struct ui_file *stream, const char *format,...)
Definition: utils.c:2361
static struct gdbarch_data * user_regs_data
Definition: user-regs.c:95
struct cmd_list_element * add_cmd(const char *name, enum command_class theclass, cmd_cfunc_ftype *fun, const char *doc, struct cmd_list_element **list)
Definition: cli-decode.c:192
struct gdbarch * get_current_arch(void)
Definition: arch-utils.c:781
#define gdb_assert(expr)
Definition: gdb_assert.h:33
const char * gdbarch_register_name(struct gdbarch *gdbarch, int regnr)
Definition: gdbarch.c:2117
static void maintenance_print_user_registers(char *args, int from_tty)
Definition: user-regs.c:222
int regnum
Definition: aarch64-tdep.c:69
int user_reg_map_name_to_regnum(struct gdbarch *gdbarch, const char *name, int len)
Definition: user-regs.c:129
struct value *( user_reg_read_ftype)(struct frame_info *frame, const void *baton)
Definition: user-regs.h:59
struct cmd_list_element * maintenanceprintlist
Definition: cli-cmds.c:167
Definition: regdef.h:22
Definition: value.c:172
const char * name
Definition: user-regs.c:43
void user_reg_add_builtin(const char *name, user_reg_read_ftype *read, const void *baton)
Definition: user-regs.c:85
struct user_reg ** last
Definition: user-regs.c:58
void deprecated_set_gdbarch_data(struct gdbarch *gdbarch, struct gdbarch_data *data, void *pointer)
Definition: gdbarch.c:4831
struct user_reg * first
Definition: user-regs.c:57
void user_reg_add(struct gdbarch *gdbarch, const char *name, user_reg_read_ftype *read, const void *baton)
Definition: user-regs.c:112
struct value * value_of_user_reg(int regnum, struct frame_info *frame)
Definition: user-regs.c:210
struct gdbarch_data * gdbarch_data_register_post_init(gdbarch_data_post_init_ftype *post_init)
Definition: gdbarch.c:4812
struct gdbarch * get_frame_arch(struct frame_info *this_frame)
Definition: frame.c:2535
const ULONGEST const LONGEST len
Definition: target.h:309