1 /* User visible, per-frame registers, for GDB, the GNU debugger.
3 Copyright (C) 2002-2020 Free Software Foundation, Inc.
5 Contributed by Red Hat.
7 This file is part of GDB.
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.
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.
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/>. */
23 #include "user-regs.h"
26 #include "arch-utils.h"
28 #include "cli/cli-cmds.h"
30 /* A table of user registers.
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.
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. */
44 /* Avoid the "read" symbol name as it conflicts with a preprocessor symbol
45 in the NetBSD header for Stack Smashing Protection, that wraps the read(2)
47 struct value
*(*xread
) (struct frame_info
* frame
, const void *baton
);
49 struct user_reg
*next
;
52 /* This structure is named gdb_user_regs instead of user_regs to avoid
53 conflicts with any "struct user_regs" in system headers. For instance,
54 on ARM GNU/Linux native builds, nm-linux.h includes <signal.h> includes
55 <sys/ucontext.h> includes <sys/procfs.h> includes <sys/user.h>, which
56 declares "struct user_regs". */
60 struct user_reg
*first
;
61 struct user_reg
**last
;
65 append_user_reg (struct gdb_user_regs
*regs
, const char *name
,
66 user_reg_read_ftype
*xread
, const void *baton
,
69 /* The caller is responsible for allocating memory needed to store
70 the register. By doing this, the function can operate on a
71 register list stored in the common heap or a specific obstack. */
72 gdb_assert (reg
!= NULL
);
78 regs
->last
= &(*regs
->last
)->next
;
81 /* An array of the builtin user registers. */
83 static struct gdb_user_regs builtin_user_regs
= {
84 NULL
, &builtin_user_regs
.first
88 user_reg_add_builtin (const char *name
, user_reg_read_ftype
*xread
,
91 append_user_reg (&builtin_user_regs
, name
, xread
, baton
,
92 XNEW (struct user_reg
));
95 /* Per-architecture user registers. Start with the builtin user
96 registers and then, again, append. */
98 static struct gdbarch_data
*user_regs_data
;
101 user_regs_init (struct gdbarch
*gdbarch
)
103 struct user_reg
*reg
;
104 struct gdb_user_regs
*regs
105 = GDBARCH_OBSTACK_ZALLOC (gdbarch
, struct gdb_user_regs
);
107 regs
->last
= ®s
->first
;
108 for (reg
= builtin_user_regs
.first
; reg
!= NULL
; reg
= reg
->next
)
109 append_user_reg (regs
, reg
->name
, reg
->xread
, reg
->baton
,
110 GDBARCH_OBSTACK_ZALLOC (gdbarch
, struct user_reg
));
115 user_reg_add (struct gdbarch
*gdbarch
, const char *name
,
116 user_reg_read_ftype
*xread
, const void *baton
)
118 struct gdb_user_regs
*regs
119 = (struct gdb_user_regs
*) gdbarch_data (gdbarch
, user_regs_data
);
123 /* ULGH, called during architecture initialization. Patch
125 regs
= (struct gdb_user_regs
*) user_regs_init (gdbarch
);
126 deprecated_set_gdbarch_data (gdbarch
, user_regs_data
, regs
);
128 append_user_reg (regs
, name
, xread
, baton
,
129 GDBARCH_OBSTACK_ZALLOC (gdbarch
, struct user_reg
));
133 user_reg_map_name_to_regnum (struct gdbarch
*gdbarch
, const char *name
,
136 /* Make life easy, set the len to something reasonable. */
140 /* Search register name space first - always let an architecture
141 specific register override the user registers. */
144 int maxregs
= gdbarch_num_cooked_regs (gdbarch
);
146 for (i
= 0; i
< maxregs
; i
++)
148 const char *regname
= gdbarch_register_name (gdbarch
, i
);
150 if (regname
!= NULL
&& len
== strlen (regname
)
151 && strncmp (regname
, name
, len
) == 0)
158 /* Search the user name space. */
160 struct gdb_user_regs
*regs
161 = (struct gdb_user_regs
*) gdbarch_data (gdbarch
, user_regs_data
);
162 struct user_reg
*reg
;
165 for (nr
= 0, reg
= regs
->first
; reg
!= NULL
; reg
= reg
->next
, nr
++)
167 if ((len
< 0 && strcmp (reg
->name
, name
))
168 || (len
== strlen (reg
->name
)
169 && strncmp (reg
->name
, name
, len
) == 0))
170 return gdbarch_num_cooked_regs (gdbarch
) + nr
;
177 static struct user_reg
*
178 usernum_to_user_reg (struct gdbarch
*gdbarch
, int usernum
)
180 struct gdb_user_regs
*regs
181 = (struct gdb_user_regs
*) gdbarch_data (gdbarch
, user_regs_data
);
182 struct user_reg
*reg
;
184 for (reg
= regs
->first
; reg
!= NULL
; reg
= reg
->next
)
194 user_reg_map_regnum_to_name (struct gdbarch
*gdbarch
, int regnum
)
196 int maxregs
= gdbarch_num_cooked_regs (gdbarch
);
200 else if (regnum
< maxregs
)
201 return gdbarch_register_name (gdbarch
, regnum
);
204 struct user_reg
*reg
= usernum_to_user_reg (gdbarch
, regnum
- maxregs
);
213 value_of_user_reg (int regnum
, struct frame_info
*frame
)
215 struct gdbarch
*gdbarch
= get_frame_arch (frame
);
216 int maxregs
= gdbarch_num_cooked_regs (gdbarch
);
217 struct user_reg
*reg
= usernum_to_user_reg (gdbarch
, regnum
- maxregs
);
219 gdb_assert (reg
!= NULL
);
220 return reg
->xread (frame
, reg
->baton
);
224 maintenance_print_user_registers (const char *args
, int from_tty
)
226 struct gdbarch
*gdbarch
= get_current_arch ();
227 struct gdb_user_regs
*regs
;
228 struct user_reg
*reg
;
231 regs
= (struct gdb_user_regs
*) gdbarch_data (gdbarch
, user_regs_data
);
232 regnum
= gdbarch_num_cooked_regs (gdbarch
);
234 fprintf_unfiltered (gdb_stdout
, " %-11s %3s\n", "Name", "Nr");
235 for (reg
= regs
->first
; reg
!= NULL
; reg
= reg
->next
, ++regnum
)
236 fprintf_unfiltered (gdb_stdout
, " %-11s %3d\n", reg
->name
, regnum
);
239 void _initialize_user_regs ();
241 _initialize_user_regs ()
243 user_regs_data
= gdbarch_data_register_post_init (user_regs_init
);
245 add_cmd ("user-registers", class_maintenance
,
246 maintenance_print_user_registers
,
247 _("List the names of the current user registers."),
248 &maintenanceprintlist
);