1/* User visible, per-frame registers, for GDB, the GNU debugger. 2 3 Copyright (C) 2002, 2003, 2004, 2007 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 "gdb_string.h" 26#include "gdb_assert.h" 27#include "frame.h" 28 29/* A table of user registers. 30 31 User registers have regnum's that live above of the range [0 32 .. gdbarch_num_regs + gdbarch_num_pseudo_regs) 33 (which is controlled by the target). 34 The target should never see a user register's regnum value. 35 36 Always append, never delete. By doing this, the relative regnum 37 (offset from gdbarch_num_regs + gdbarch_num_pseudo_regs) 38 assigned to each user register never changes. */ 39 40struct user_reg 41{ 42 const char *name; 43 struct value *(*read) (struct frame_info * frame, const void *baton); 44 const void *baton; 45 struct user_reg *next; 46}; 47 48/* This structure is named gdb_user_regs instead of user_regs to avoid 49 conflicts with any "struct user_regs" in system headers. For instance, 50 on ARM GNU/Linux native builds, nm-linux.h includes <signal.h> includes 51 <sys/ucontext.h> includes <sys/procfs.h> includes <sys/user.h>, which 52 declares "struct user_regs". */ 53 54struct gdb_user_regs 55{ 56 struct user_reg *first; 57 struct user_reg **last; 58}; 59 60static void 61append_user_reg (struct gdb_user_regs *regs, const char *name, 62 user_reg_read_ftype *read, const void *baton, 63 struct user_reg *reg) 64{ 65 /* The caller is responsible for allocating memory needed to store 66 the register. By doing this, the function can operate on a 67 register list stored in the common heap or a specific obstack. */ 68 gdb_assert (reg != NULL); 69 reg->name = name; 70 reg->read = read; 71 reg->baton = baton; 72 reg->next = NULL; 73 (*regs->last) = reg; 74 regs->last = &(*regs->last)->next; 75} 76 77/* An array of the builtin user registers. */ 78 79static struct gdb_user_regs builtin_user_regs = { NULL, &builtin_user_regs.first }; 80 81void 82user_reg_add_builtin (const char *name, user_reg_read_ftype *read, 83 const void *baton) 84{ 85 append_user_reg (&builtin_user_regs, name, read, baton, 86 XMALLOC (struct user_reg)); 87} 88 89/* Per-architecture user registers. Start with the builtin user 90 registers and then, again, append. */ 91 92static struct gdbarch_data *user_regs_data; 93 94static void * 95user_regs_init (struct gdbarch *gdbarch) 96{ 97 struct user_reg *reg; 98 struct gdb_user_regs *regs = GDBARCH_OBSTACK_ZALLOC (gdbarch, struct gdb_user_regs); 99 regs->last = ®s->first; 100 for (reg = builtin_user_regs.first; reg != NULL; reg = reg->next) 101 append_user_reg (regs, reg->name, reg->read, reg->baton, 102 GDBARCH_OBSTACK_ZALLOC (gdbarch, struct user_reg)); 103 return regs; 104} 105 106void 107user_reg_add (struct gdbarch *gdbarch, const char *name, 108 user_reg_read_ftype *read, const void *baton) 109{ 110 struct gdb_user_regs *regs = gdbarch_data (gdbarch, user_regs_data); 111 if (regs == NULL) 112 { 113 /* ULGH, called during architecture initialization. Patch 114 things up. */ 115 regs = user_regs_init (gdbarch); 116 deprecated_set_gdbarch_data (gdbarch, user_regs_data, regs); 117 } 118 append_user_reg (regs, name, read, baton, 119 GDBARCH_OBSTACK_ZALLOC (gdbarch, struct user_reg)); 120} 121 122int 123user_reg_map_name_to_regnum (struct gdbarch *gdbarch, const char *name, 124 int len) 125{ 126 /* Make life easy, set the len to something reasonable. */ 127 if (len < 0) 128 len = strlen (name); 129 130 /* Search register name space first - always let an architecture 131 specific register override the user registers. */ 132 { 133 int i; 134 int maxregs = (gdbarch_num_regs (gdbarch) 135 + gdbarch_num_pseudo_regs (gdbarch)); 136 for (i = 0; i < maxregs; i++) 137 { 138 const char *regname = gdbarch_register_name (gdbarch, i); 139 if (regname != NULL && len == strlen (regname) 140 && strncmp (regname, name, len) == 0) 141 { 142 return i; 143 } 144 } 145 } 146 147 /* Search the user name space. */ 148 { 149 struct gdb_user_regs *regs = gdbarch_data (gdbarch, user_regs_data); 150 struct user_reg *reg; 151 int nr; 152 for (nr = 0, reg = regs->first; reg != NULL; reg = reg->next, nr++) 153 { 154 if ((len < 0 && strcmp (reg->name, name)) 155 || (len == strlen (reg->name) 156 && strncmp (reg->name, name, len) == 0)) 157 return gdbarch_num_regs (current_gdbarch) 158 + gdbarch_num_pseudo_regs (current_gdbarch) + nr; 159 } 160 } 161 162 return -1; 163} 164 165static struct user_reg * 166usernum_to_user_reg (struct gdbarch *gdbarch, int usernum) 167{ 168 struct gdb_user_regs *regs = gdbarch_data (gdbarch, user_regs_data); 169 struct user_reg *reg; 170 for (reg = regs->first; reg != NULL; reg = reg->next) 171 { 172 if (usernum == 0) 173 return reg; 174 usernum--; 175 } 176 return NULL; 177} 178 179const char * 180user_reg_map_regnum_to_name (struct gdbarch *gdbarch, int regnum) 181{ 182 int maxregs = (gdbarch_num_regs (gdbarch) 183 + gdbarch_num_pseudo_regs (gdbarch)); 184 if (regnum < 0) 185 return NULL; 186 else if (regnum < maxregs) 187 return gdbarch_register_name (gdbarch, regnum); 188 else 189 { 190 struct user_reg *reg = usernum_to_user_reg (gdbarch, regnum - maxregs); 191 if (reg == NULL) 192 return NULL; 193 else 194 return reg->name; 195 } 196} 197 198struct value * 199value_of_user_reg (int regnum, struct frame_info *frame) 200{ 201 struct gdbarch *gdbarch = get_frame_arch (frame); 202 int maxregs = (gdbarch_num_regs (gdbarch) 203 + gdbarch_num_pseudo_regs (gdbarch)); 204 struct user_reg *reg = usernum_to_user_reg (gdbarch, regnum - maxregs); 205 gdb_assert (reg != NULL); 206 return reg->read (frame, reg->baton); 207} 208 209extern initialize_file_ftype _initialize_user_regs; /* -Wmissing-prototypes */ 210 211void 212_initialize_user_regs (void) 213{ 214 user_regs_data = gdbarch_data_register_post_init (user_regs_init); 215} 216