1 /* Builtin frame register, for GDB, the GNU debugger.
2
3 Copyright (C) 2002-2024 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 "user-regs.h"
23 #include "frame.h"
24 #include "gdbtypes.h"
25 #include "value.h"
26 #include "gdbarch.h"
27
28 static struct value *
value_of_builtin_frame_fp_reg(const frame_info_ptr & frame,const void * baton)29 value_of_builtin_frame_fp_reg (const frame_info_ptr &frame, const void *baton)
30 {
31 struct gdbarch *gdbarch = get_frame_arch (frame);
32
33 if (gdbarch_deprecated_fp_regnum (gdbarch) >= 0)
34 /* NOTE: cagney/2003-04-24: Since the mere presence of "fp" in the
35 register name table overrides this built-in $fp register, there
36 is no real reason for this gdbarch_deprecated_fp_regnum trickery here.
37 An architecture wanting to implement "$fp" as alias for a raw
38 register can do so by adding "fp" to register name table (mind
39 you, doing this is probably a dangerous thing). */
40 return value_of_register (gdbarch_deprecated_fp_regnum (gdbarch),
41 get_next_frame_sentinel_okay (frame));
42 else
43 {
44 struct type *data_ptr_type = builtin_type (gdbarch)->builtin_data_ptr;
45 struct value *val = value::allocate (data_ptr_type);
46 gdb_byte *buf = val->contents_raw ().data ();
47
48 gdbarch_address_to_pointer (gdbarch, data_ptr_type,
49 buf, get_frame_base_address (frame));
50 return val;
51 }
52 }
53
54 static struct value *
value_of_builtin_frame_pc_reg(const frame_info_ptr & frame,const void * baton)55 value_of_builtin_frame_pc_reg (const frame_info_ptr &frame, const void *baton)
56 {
57 struct gdbarch *gdbarch = get_frame_arch (frame);
58
59 if (gdbarch_pc_regnum (gdbarch) >= 0)
60 return value_of_register (gdbarch_pc_regnum (gdbarch),
61 get_next_frame_sentinel_okay (frame));
62 else
63 {
64 struct type *func_ptr_type = builtin_type (gdbarch)->builtin_func_ptr;
65 struct value *val = value::allocate (func_ptr_type);
66 gdb_byte *buf = val->contents_raw ().data ();
67
68 gdbarch_address_to_pointer (gdbarch, func_ptr_type,
69 buf, get_frame_pc (frame));
70 return val;
71 }
72 }
73
74 static struct value *
value_of_builtin_frame_sp_reg(const frame_info_ptr & frame,const void * baton)75 value_of_builtin_frame_sp_reg (const frame_info_ptr &frame, const void *baton)
76 {
77 struct gdbarch *gdbarch = get_frame_arch (frame);
78
79 if (gdbarch_sp_regnum (gdbarch) >= 0)
80 return value_of_register (gdbarch_sp_regnum (gdbarch),
81 get_next_frame_sentinel_okay (frame));
82 error (_("Standard register ``$sp'' is not available for this target"));
83 }
84
85 static struct value *
value_of_builtin_frame_ps_reg(const frame_info_ptr & frame,const void * baton)86 value_of_builtin_frame_ps_reg (const frame_info_ptr &frame, const void *baton)
87 {
88 struct gdbarch *gdbarch = get_frame_arch (frame);
89
90 if (gdbarch_ps_regnum (gdbarch) >= 0)
91 return value_of_register (gdbarch_ps_regnum (gdbarch),
92 get_next_frame_sentinel_okay (frame));
93 error (_("Standard register ``$ps'' is not available for this target"));
94 }
95
96 void _initialize_frame_reg ();
97 void
_initialize_frame_reg()98 _initialize_frame_reg ()
99 {
100 /* Frame based $fp, $pc, $sp and $ps. These only come into play
101 when the target does not define its own version of these
102 registers. */
103 user_reg_add_builtin ("fp", value_of_builtin_frame_fp_reg, NULL);
104 user_reg_add_builtin ("pc", value_of_builtin_frame_pc_reg, NULL);
105 user_reg_add_builtin ("sp", value_of_builtin_frame_sp_reg, NULL);
106 user_reg_add_builtin ("ps", value_of_builtin_frame_ps_reg, NULL);
107 }
108