1 /* Generic simulator watchpoint support. 2 Copyright (C) 1997-2023 Free Software Foundation, Inc. 3 Contributed by Cygnus Support. 4 5 This file is part of GDB, the GNU debugger. 6 7 This program is free software; you can redistribute it and/or modify 8 it under the terms of the GNU General Public License as published by 9 the Free Software Foundation; either version 3 of the License, or 10 (at your option) any later version. 11 12 This program is distributed in the hope that it will be useful, 13 but WITHOUT ANY WARRANTY; without even the implied warranty of 14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 15 GNU General Public License for more details. 16 17 You should have received a copy of the GNU General Public License 18 along with this program. If not, see <http://www.gnu.org/licenses/>. */ 19 20 /* This must come before any other includes. */ 21 #include "defs.h" 22 23 #include <ctype.h> 24 #include <stdio.h> 25 #include <stdlib.h> 26 #include <string.h> 27 28 #include "libiberty.h" 29 30 #include "sim-main.h" 31 #include "sim-options.h" 32 #include "sim-signal.h" 33 #include "sim-assert.h" 34 35 enum { 36 OPTION_WATCH_DELETE = OPTION_START, 37 38 OPTION_WATCH_INFO, 39 OPTION_WATCH_CLOCK, 40 OPTION_WATCH_CYCLES, 41 OPTION_WATCH_PC, 42 43 OPTION_WATCH_OP, 44 }; 45 46 47 /* Break an option number into its op/int-nr */ 48 static watchpoint_type 49 option_to_type (SIM_DESC sd, 50 int option) 51 { 52 sim_watchpoints *watch = STATE_WATCHPOINTS (sd); 53 watchpoint_type type = ((option - OPTION_WATCH_OP) 54 / (watch->nr_interrupts + 1)); 55 SIM_ASSERT (type >= 0 && type < nr_watchpoint_types); 56 return type; 57 } 58 59 static int 60 option_to_interrupt_nr (SIM_DESC sd, 61 int option) 62 { 63 sim_watchpoints *watch = STATE_WATCHPOINTS (sd); 64 int interrupt_nr = ((option - OPTION_WATCH_OP) 65 % (watch->nr_interrupts + 1)); 66 return interrupt_nr; 67 } 68 69 static int 70 type_to_option (SIM_DESC sd, 71 watchpoint_type type, 72 int interrupt_nr) 73 { 74 sim_watchpoints *watch = STATE_WATCHPOINTS (sd); 75 return ((type * (watch->nr_interrupts + 1)) 76 + interrupt_nr 77 + OPTION_WATCH_OP); 78 } 79 80 81 /* Delete one or more watchpoints. Fail if no watchpoints were found */ 82 83 static SIM_RC 84 do_watchpoint_delete (SIM_DESC sd, 85 int ident, 86 watchpoint_type type) 87 { 88 sim_watchpoints *watch = STATE_WATCHPOINTS (sd); 89 sim_watch_point **entry = &watch->points; 90 SIM_RC status = SIM_RC_FAIL; 91 while ((*entry) != NULL) 92 { 93 if ((*entry)->ident == ident 94 || (*entry)->type == type) 95 { 96 sim_watch_point *dead = (*entry); 97 (*entry) = (*entry)->next; 98 sim_events_deschedule (sd, dead->event); 99 free (dead); 100 status = SIM_RC_OK; 101 } 102 else 103 entry = &(*entry)->next; 104 } 105 return status; 106 } 107 108 static const char * 109 watchpoint_type_to_str (SIM_DESC sd, 110 watchpoint_type type) 111 { 112 switch (type) 113 { 114 case pc_watchpoint: 115 return "pc"; 116 case clock_watchpoint: 117 return "clock"; 118 case cycles_watchpoint: 119 return "cycles"; 120 case invalid_watchpoint: 121 case nr_watchpoint_types: 122 return "(invalid-type)"; 123 } 124 return NULL; 125 } 126 127 static const char * 128 interrupt_nr_to_str (SIM_DESC sd, 129 int interrupt_nr) 130 { 131 sim_watchpoints *watch = STATE_WATCHPOINTS (sd); 132 if (interrupt_nr < 0) 133 return "(invalid-interrupt)"; 134 else if (interrupt_nr >= watch->nr_interrupts) 135 return "breakpoint"; 136 else 137 return watch->interrupt_names[interrupt_nr]; 138 } 139 140 141 static void 142 do_watchpoint_info (SIM_DESC sd) 143 { 144 sim_watchpoints *watch = STATE_WATCHPOINTS (sd); 145 sim_watch_point *point; 146 sim_io_printf (sd, "Watchpoints:\n"); 147 for (point = watch->points; point != NULL; point = point->next) 148 { 149 sim_io_printf (sd, "%3d: watch %s %s ", 150 point->ident, 151 watchpoint_type_to_str (sd, point->type), 152 interrupt_nr_to_str (sd, point->interrupt_nr)); 153 if (point->is_periodic) 154 sim_io_printf (sd, "+"); 155 if (!point->is_within) 156 sim_io_printf (sd, "!"); 157 sim_io_printf (sd, "0x%lx", point->arg0); 158 if (point->arg1 != point->arg0) 159 sim_io_printf (sd, ",0x%lx", point->arg1); 160 sim_io_printf (sd, "\n"); 161 } 162 } 163 164 165 166 static sim_event_handler handle_watchpoint; 167 168 static SIM_RC 169 schedule_watchpoint (SIM_DESC sd, 170 sim_watch_point *point) 171 { 172 sim_watchpoints *watch = STATE_WATCHPOINTS (sd); 173 174 switch (point->type) 175 { 176 case pc_watchpoint: 177 point->event = sim_events_watch_pc (sd, 178 point->is_within, 179 point->arg0, point->arg1, 180 /* PC in arg0..arg1 */ 181 handle_watchpoint, 182 point); 183 return SIM_RC_OK; 184 case clock_watchpoint: 185 point->event = sim_events_watch_clock (sd, 186 point->arg0, /* ms time */ 187 handle_watchpoint, 188 point); 189 return SIM_RC_OK; 190 case cycles_watchpoint: 191 point->event = sim_events_schedule (sd, 192 point->arg0, /* time */ 193 handle_watchpoint, 194 point); 195 return SIM_RC_OK; 196 default: 197 sim_engine_abort (sd, NULL, NULL_CIA, 198 "handle_watchpoint - internal error - bad switch"); 199 return SIM_RC_FAIL; 200 } 201 return SIM_RC_OK; 202 } 203 204 205 static void 206 handle_watchpoint (SIM_DESC sd, void *data) 207 { 208 sim_watchpoints *watch = STATE_WATCHPOINTS (sd); 209 sim_watch_point *point = (sim_watch_point *) data; 210 int interrupt_nr = point->interrupt_nr; 211 212 if (point->is_periodic) 213 /* reschedule this event before processing it */ 214 schedule_watchpoint (sd, point); 215 else 216 do_watchpoint_delete (sd, point->ident, invalid_watchpoint); 217 218 if (point->interrupt_nr == watch->nr_interrupts) 219 sim_engine_halt (sd, NULL, NULL, NULL_CIA, sim_stopped, SIM_SIGINT); 220 else 221 watch->interrupt_handler (sd, &watch->interrupt_names[interrupt_nr]); 222 } 223 224 225 static SIM_RC 226 do_watchpoint_create (SIM_DESC sd, 227 watchpoint_type type, 228 int opt, 229 char *arg) 230 { 231 sim_watchpoints *watch = STATE_WATCHPOINTS (sd); 232 sim_watch_point **point; 233 234 /* create the watchpoint */ 235 point = &watch->points; 236 while ((*point) != NULL) 237 point = &(*point)->next; 238 (*point) = ZALLOC (sim_watch_point); 239 240 /* fill in the details */ 241 (*point)->ident = ++(watch->last_point_nr); 242 (*point)->type = option_to_type (sd, opt); 243 (*point)->interrupt_nr = option_to_interrupt_nr (sd, opt); 244 /* prefixes to arg - +== periodic, !==not or outside */ 245 (*point)->is_within = 1; 246 while (1) 247 { 248 if (arg[0] == '+') 249 (*point)->is_periodic = 1; 250 else if (arg[0] == '!') 251 (*point)->is_within = 0; 252 else 253 break; 254 arg++; 255 } 256 257 (*point)->arg0 = strtoul (arg, &arg, 0); 258 if (arg[0] == ',') 259 (*point)->arg1 = strtoul (arg + 1, NULL, 0); 260 else 261 (*point)->arg1 = (*point)->arg0; 262 263 /* schedule it */ 264 schedule_watchpoint (sd, (*point)); 265 266 return SIM_RC_OK; 267 } 268 269 270 static SIM_RC 271 watchpoint_option_handler (SIM_DESC sd, sim_cpu *cpu, int opt, 272 char *arg, int is_command) 273 { 274 if (opt >= OPTION_WATCH_OP) 275 return do_watchpoint_create (sd, clock_watchpoint, opt, arg); 276 else 277 switch (opt) 278 { 279 280 case OPTION_WATCH_DELETE: 281 if (isdigit ((int) arg[0])) 282 { 283 int ident = strtol (arg, NULL, 0); 284 if (do_watchpoint_delete (sd, ident, invalid_watchpoint) 285 != SIM_RC_OK) 286 { 287 sim_io_eprintf (sd, "Watchpoint %d not found\n", ident); 288 return SIM_RC_FAIL; 289 } 290 return SIM_RC_OK; 291 } 292 else if (strcasecmp (arg, "all") == 0) 293 { 294 watchpoint_type type; 295 for (type = invalid_watchpoint + 1; 296 type < nr_watchpoint_types; 297 type++) 298 { 299 do_watchpoint_delete (sd, 0, type); 300 } 301 return SIM_RC_OK; 302 } 303 else if (strcasecmp (arg, "pc") == 0) 304 { 305 if (do_watchpoint_delete (sd, 0, pc_watchpoint) 306 != SIM_RC_OK) 307 { 308 sim_io_eprintf (sd, "No PC watchpoints found\n"); 309 return SIM_RC_FAIL; 310 } 311 return SIM_RC_OK; 312 } 313 else if (strcasecmp (arg, "clock") == 0) 314 { 315 if (do_watchpoint_delete (sd, 0, clock_watchpoint) != SIM_RC_OK) 316 { 317 sim_io_eprintf (sd, "No CLOCK watchpoints found\n"); 318 return SIM_RC_FAIL; 319 } 320 return SIM_RC_OK; 321 } 322 else if (strcasecmp (arg, "cycles") == 0) 323 { 324 if (do_watchpoint_delete (sd, 0, cycles_watchpoint) != SIM_RC_OK) 325 { 326 sim_io_eprintf (sd, "No CYCLES watchpoints found\n"); 327 return SIM_RC_FAIL; 328 } 329 return SIM_RC_OK; 330 } 331 sim_io_eprintf (sd, "Unknown watchpoint type `%s'\n", arg); 332 return SIM_RC_FAIL; 333 334 case OPTION_WATCH_INFO: 335 { 336 do_watchpoint_info (sd); 337 return SIM_RC_OK; 338 } 339 340 default: 341 sim_io_eprintf (sd, "Unknown watch option %d\n", opt); 342 return SIM_RC_FAIL; 343 344 } 345 346 } 347 348 349 static SIM_RC 350 sim_watchpoint_init (SIM_DESC sd) 351 { 352 sim_watchpoints *watch = STATE_WATCHPOINTS (sd); 353 sim_watch_point *point; 354 /* NOTE: Do not need to de-schedule any previous watchpoints as 355 sim-events has already done this */ 356 /* schedule any watchpoints enabled by command line options */ 357 for (point = watch->points; point != NULL; point = point->next) 358 { 359 schedule_watchpoint (sd, point); 360 } 361 return SIM_RC_OK; 362 } 363 364 365 static const OPTION watchpoint_options[] = 366 { 367 { {"watch-delete", required_argument, NULL, OPTION_WATCH_DELETE }, 368 '\0', "IDENT|all|pc|cycles|clock", "Delete a watchpoint", 369 watchpoint_option_handler, NULL }, 370 371 { {"watch-info", no_argument, NULL, OPTION_WATCH_INFO }, 372 '\0', NULL, "List scheduled watchpoints", 373 watchpoint_option_handler, NULL }, 374 375 { {NULL, no_argument, NULL, 0}, '\0', NULL, NULL, NULL, NULL } 376 }; 377 378 static const char *default_interrupt_names[] = { "int", 0, }; 379 380 /* This default handler is "good enough" for targets that just want to trap into 381 gdb when watchpoints are hit, and have only configured the STATE_WATCHPOINTS 382 pc field. */ 383 static void 384 default_interrupt_handler (SIM_DESC sd, void *data) 385 { 386 sim_cpu *cpu = STATE_CPU (sd, 0); 387 address_word cia = CPU_PC_GET (cpu); 388 sim_engine_halt (sd, cpu, NULL, cia, sim_stopped, SIM_SIGTRAP); 389 } 390 391 SIM_RC 392 sim_watchpoint_install (SIM_DESC sd) 393 { 394 sim_watchpoints *watch = STATE_WATCHPOINTS (sd); 395 SIM_ASSERT (STATE_MAGIC (sd) == SIM_MAGIC_NUMBER); 396 /* the basic command set */ 397 sim_module_add_init_fn (sd, sim_watchpoint_init); 398 sim_add_option_table (sd, NULL, watchpoint_options); 399 /* fill in some details */ 400 if (watch->interrupt_names == NULL) 401 watch->interrupt_names = default_interrupt_names; 402 if (watch->interrupt_handler == NULL) 403 watch->interrupt_handler = default_interrupt_handler; 404 watch->nr_interrupts = 0; 405 while (watch->interrupt_names[watch->nr_interrupts] != NULL) 406 watch->nr_interrupts++; 407 /* generate more advansed commands */ 408 { 409 OPTION *int_options = NZALLOC (OPTION, 1 + (watch->nr_interrupts + 1) * nr_watchpoint_types); 410 int interrupt_nr; 411 for (interrupt_nr = 0; interrupt_nr <= watch->nr_interrupts; interrupt_nr++) 412 { 413 watchpoint_type type; 414 for (type = 0; type < nr_watchpoint_types; type++) 415 { 416 char *name; 417 int nr = interrupt_nr * nr_watchpoint_types + type; 418 OPTION *option = &int_options[nr]; 419 if (asprintf (&name, "watch-%s-%s", 420 watchpoint_type_to_str (sd, type), 421 interrupt_nr_to_str (sd, interrupt_nr)) < 0) 422 return SIM_RC_FAIL; 423 option->opt.name = name; 424 option->opt.has_arg = required_argument; 425 option->opt.val = type_to_option (sd, type, interrupt_nr); 426 option->doc = ""; 427 option->doc_name = ""; 428 option->handler = watchpoint_option_handler; 429 } 430 } 431 /* adjust first few entries so that they contain real 432 documentation, the first entry includes a list of actions. */ 433 { 434 const char *prefix = 435 "Watch the simulator, take ACTION in COUNT cycles (`+' for every COUNT cycles), ACTION is"; 436 char *doc; 437 int len = strlen (prefix) + 1; 438 for (interrupt_nr = 0; interrupt_nr <= watch->nr_interrupts; interrupt_nr++) 439 len += strlen (interrupt_nr_to_str (sd, interrupt_nr)) + 1; 440 doc = NZALLOC (char, len); 441 strcpy (doc, prefix); 442 for (interrupt_nr = 0; interrupt_nr <= watch->nr_interrupts; interrupt_nr++) 443 { 444 strcat (doc, " "); 445 strcat (doc, interrupt_nr_to_str (sd, interrupt_nr)); 446 } 447 int_options[0].doc_name = "watch-cycles-ACTION"; 448 int_options[0].arg = "[+]COUNT"; 449 int_options[0].doc = doc; 450 } 451 int_options[1].doc_name = "watch-pc-ACTION"; 452 int_options[1].arg = "[!]ADDRESS"; 453 int_options[1].doc = 454 "Watch the PC, take ACTION when matches ADDRESS (in range ADDRESS,ADDRESS), `!' negates test"; 455 int_options[2].doc_name = "watch-clock-ACTION"; 456 int_options[2].arg = "[+]MILLISECONDS"; 457 int_options[2].doc = 458 "Watch the clock, take ACTION after MILLISECONDS (`+' for every MILLISECONDS)"; 459 460 sim_add_option_table (sd, NULL, int_options); 461 } 462 return SIM_RC_OK; 463 } 464