| 1 | /* Branch trace support for GDB, the GNU debugger. |
| 2 | |
| 3 | Copyright (C) 2013-2015 Free Software Foundation, Inc. |
| 4 | |
| 5 | Contributed by Intel Corp. <markus.t.metzger@intel.com> |
| 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 "btrace.h" |
| 24 | #include "gdbthread.h" |
| 25 | #include "inferior.h" |
| 26 | #include "target.h" |
| 27 | #include "record.h" |
| 28 | #include "symtab.h" |
| 29 | #include "disasm.h" |
| 30 | #include "source.h" |
| 31 | #include "filenames.h" |
| 32 | #include "xml-support.h" |
| 33 | #include "regcache.h" |
| 34 | |
| 35 | /* Print a record debug message. Use do ... while (0) to avoid ambiguities |
| 36 | when used in if statements. */ |
| 37 | |
| 38 | #define DEBUG(msg, args...) \ |
| 39 | do \ |
| 40 | { \ |
| 41 | if (record_debug != 0) \ |
| 42 | fprintf_unfiltered (gdb_stdlog, \ |
| 43 | "[btrace] " msg "\n", ##args); \ |
| 44 | } \ |
| 45 | while (0) |
| 46 | |
| 47 | #define DEBUG_FTRACE(msg, args...) DEBUG ("[ftrace] " msg, ##args) |
| 48 | |
| 49 | /* Return the function name of a recorded function segment for printing. |
| 50 | This function never returns NULL. */ |
| 51 | |
| 52 | static const char * |
| 53 | ftrace_print_function_name (const struct btrace_function *bfun) |
| 54 | { |
| 55 | struct minimal_symbol *msym; |
| 56 | struct symbol *sym; |
| 57 | |
| 58 | msym = bfun->msym; |
| 59 | sym = bfun->sym; |
| 60 | |
| 61 | if (sym != NULL) |
| 62 | return SYMBOL_PRINT_NAME (sym); |
| 63 | |
| 64 | if (msym != NULL) |
| 65 | return MSYMBOL_PRINT_NAME (msym); |
| 66 | |
| 67 | return "<unknown>"; |
| 68 | } |
| 69 | |
| 70 | /* Return the file name of a recorded function segment for printing. |
| 71 | This function never returns NULL. */ |
| 72 | |
| 73 | static const char * |
| 74 | ftrace_print_filename (const struct btrace_function *bfun) |
| 75 | { |
| 76 | struct symbol *sym; |
| 77 | const char *filename; |
| 78 | |
| 79 | sym = bfun->sym; |
| 80 | |
| 81 | if (sym != NULL) |
| 82 | filename = symtab_to_filename_for_display (symbol_symtab (sym)); |
| 83 | else |
| 84 | filename = "<unknown>"; |
| 85 | |
| 86 | return filename; |
| 87 | } |
| 88 | |
| 89 | /* Return a string representation of the address of an instruction. |
| 90 | This function never returns NULL. */ |
| 91 | |
| 92 | static const char * |
| 93 | ftrace_print_insn_addr (const struct btrace_insn *insn) |
| 94 | { |
| 95 | if (insn == NULL) |
| 96 | return "<nil>"; |
| 97 | |
| 98 | return core_addr_to_string_nz (insn->pc); |
| 99 | } |
| 100 | |
| 101 | /* Print an ftrace debug status message. */ |
| 102 | |
| 103 | static void |
| 104 | ftrace_debug (const struct btrace_function *bfun, const char *prefix) |
| 105 | { |
| 106 | const char *fun, *file; |
| 107 | unsigned int ibegin, iend; |
| 108 | int level; |
| 109 | |
| 110 | fun = ftrace_print_function_name (bfun); |
| 111 | file = ftrace_print_filename (bfun); |
| 112 | level = bfun->level; |
| 113 | |
| 114 | ibegin = bfun->insn_offset; |
| 115 | iend = ibegin + VEC_length (btrace_insn_s, bfun->insn); |
| 116 | |
| 117 | DEBUG_FTRACE ("%s: fun = %s, file = %s, level = %d, insn = [%u; %u)", |
| 118 | prefix, fun, file, level, ibegin, iend); |
| 119 | } |
| 120 | |
| 121 | /* Return non-zero if BFUN does not match MFUN and FUN, |
| 122 | return zero otherwise. */ |
| 123 | |
| 124 | static int |
| 125 | ftrace_function_switched (const struct btrace_function *bfun, |
| 126 | const struct minimal_symbol *mfun, |
| 127 | const struct symbol *fun) |
| 128 | { |
| 129 | struct minimal_symbol *msym; |
| 130 | struct symbol *sym; |
| 131 | |
| 132 | msym = bfun->msym; |
| 133 | sym = bfun->sym; |
| 134 | |
| 135 | /* If the minimal symbol changed, we certainly switched functions. */ |
| 136 | if (mfun != NULL && msym != NULL |
| 137 | && strcmp (MSYMBOL_LINKAGE_NAME (mfun), MSYMBOL_LINKAGE_NAME (msym)) != 0) |
| 138 | return 1; |
| 139 | |
| 140 | /* If the symbol changed, we certainly switched functions. */ |
| 141 | if (fun != NULL && sym != NULL) |
| 142 | { |
| 143 | const char *bfname, *fname; |
| 144 | |
| 145 | /* Check the function name. */ |
| 146 | if (strcmp (SYMBOL_LINKAGE_NAME (fun), SYMBOL_LINKAGE_NAME (sym)) != 0) |
| 147 | return 1; |
| 148 | |
| 149 | /* Check the location of those functions, as well. */ |
| 150 | bfname = symtab_to_fullname (symbol_symtab (sym)); |
| 151 | fname = symtab_to_fullname (symbol_symtab (fun)); |
| 152 | if (filename_cmp (fname, bfname) != 0) |
| 153 | return 1; |
| 154 | } |
| 155 | |
| 156 | /* If we lost symbol information, we switched functions. */ |
| 157 | if (!(msym == NULL && sym == NULL) && mfun == NULL && fun == NULL) |
| 158 | return 1; |
| 159 | |
| 160 | /* If we gained symbol information, we switched functions. */ |
| 161 | if (msym == NULL && sym == NULL && !(mfun == NULL && fun == NULL)) |
| 162 | return 1; |
| 163 | |
| 164 | return 0; |
| 165 | } |
| 166 | |
| 167 | /* Allocate and initialize a new branch trace function segment. |
| 168 | PREV is the chronologically preceding function segment. |
| 169 | MFUN and FUN are the symbol information we have for this function. */ |
| 170 | |
| 171 | static struct btrace_function * |
| 172 | ftrace_new_function (struct btrace_function *prev, |
| 173 | struct minimal_symbol *mfun, |
| 174 | struct symbol *fun) |
| 175 | { |
| 176 | struct btrace_function *bfun; |
| 177 | |
| 178 | bfun = xzalloc (sizeof (*bfun)); |
| 179 | |
| 180 | bfun->msym = mfun; |
| 181 | bfun->sym = fun; |
| 182 | bfun->flow.prev = prev; |
| 183 | |
| 184 | if (prev == NULL) |
| 185 | { |
| 186 | /* Start counting at one. */ |
| 187 | bfun->number = 1; |
| 188 | bfun->insn_offset = 1; |
| 189 | } |
| 190 | else |
| 191 | { |
| 192 | gdb_assert (prev->flow.next == NULL); |
| 193 | prev->flow.next = bfun; |
| 194 | |
| 195 | bfun->number = prev->number + 1; |
| 196 | bfun->insn_offset = (prev->insn_offset |
| 197 | + VEC_length (btrace_insn_s, prev->insn)); |
| 198 | bfun->level = prev->level; |
| 199 | } |
| 200 | |
| 201 | return bfun; |
| 202 | } |
| 203 | |
| 204 | /* Update the UP field of a function segment. */ |
| 205 | |
| 206 | static void |
| 207 | ftrace_update_caller (struct btrace_function *bfun, |
| 208 | struct btrace_function *caller, |
| 209 | enum btrace_function_flag flags) |
| 210 | { |
| 211 | if (bfun->up != NULL) |
| 212 | ftrace_debug (bfun, "updating caller"); |
| 213 | |
| 214 | bfun->up = caller; |
| 215 | bfun->flags = flags; |
| 216 | |
| 217 | ftrace_debug (bfun, "set caller"); |
| 218 | } |
| 219 | |
| 220 | /* Fix up the caller for all segments of a function. */ |
| 221 | |
| 222 | static void |
| 223 | ftrace_fixup_caller (struct btrace_function *bfun, |
| 224 | struct btrace_function *caller, |
| 225 | enum btrace_function_flag flags) |
| 226 | { |
| 227 | struct btrace_function *prev, *next; |
| 228 | |
| 229 | ftrace_update_caller (bfun, caller, flags); |
| 230 | |
| 231 | /* Update all function segments belonging to the same function. */ |
| 232 | for (prev = bfun->segment.prev; prev != NULL; prev = prev->segment.prev) |
| 233 | ftrace_update_caller (prev, caller, flags); |
| 234 | |
| 235 | for (next = bfun->segment.next; next != NULL; next = next->segment.next) |
| 236 | ftrace_update_caller (next, caller, flags); |
| 237 | } |
| 238 | |
| 239 | /* Add a new function segment for a call. |
| 240 | CALLER is the chronologically preceding function segment. |
| 241 | MFUN and FUN are the symbol information we have for this function. */ |
| 242 | |
| 243 | static struct btrace_function * |
| 244 | ftrace_new_call (struct btrace_function *caller, |
| 245 | struct minimal_symbol *mfun, |
| 246 | struct symbol *fun) |
| 247 | { |
| 248 | struct btrace_function *bfun; |
| 249 | |
| 250 | bfun = ftrace_new_function (caller, mfun, fun); |
| 251 | bfun->up = caller; |
| 252 | bfun->level += 1; |
| 253 | |
| 254 | ftrace_debug (bfun, "new call"); |
| 255 | |
| 256 | return bfun; |
| 257 | } |
| 258 | |
| 259 | /* Add a new function segment for a tail call. |
| 260 | CALLER is the chronologically preceding function segment. |
| 261 | MFUN and FUN are the symbol information we have for this function. */ |
| 262 | |
| 263 | static struct btrace_function * |
| 264 | ftrace_new_tailcall (struct btrace_function *caller, |
| 265 | struct minimal_symbol *mfun, |
| 266 | struct symbol *fun) |
| 267 | { |
| 268 | struct btrace_function *bfun; |
| 269 | |
| 270 | bfun = ftrace_new_function (caller, mfun, fun); |
| 271 | bfun->up = caller; |
| 272 | bfun->level += 1; |
| 273 | bfun->flags |= BFUN_UP_LINKS_TO_TAILCALL; |
| 274 | |
| 275 | ftrace_debug (bfun, "new tail call"); |
| 276 | |
| 277 | return bfun; |
| 278 | } |
| 279 | |
| 280 | /* Find the innermost caller in the back trace of BFUN with MFUN/FUN |
| 281 | symbol information. */ |
| 282 | |
| 283 | static struct btrace_function * |
| 284 | ftrace_find_caller (struct btrace_function *bfun, |
| 285 | struct minimal_symbol *mfun, |
| 286 | struct symbol *fun) |
| 287 | { |
| 288 | for (; bfun != NULL; bfun = bfun->up) |
| 289 | { |
| 290 | /* Skip functions with incompatible symbol information. */ |
| 291 | if (ftrace_function_switched (bfun, mfun, fun)) |
| 292 | continue; |
| 293 | |
| 294 | /* This is the function segment we're looking for. */ |
| 295 | break; |
| 296 | } |
| 297 | |
| 298 | return bfun; |
| 299 | } |
| 300 | |
| 301 | /* Find the innermost caller in the back trace of BFUN, skipping all |
| 302 | function segments that do not end with a call instruction (e.g. |
| 303 | tail calls ending with a jump). */ |
| 304 | |
| 305 | static struct btrace_function * |
| 306 | ftrace_find_call (struct btrace_function *bfun) |
| 307 | { |
| 308 | for (; bfun != NULL; bfun = bfun->up) |
| 309 | { |
| 310 | struct btrace_insn *last; |
| 311 | |
| 312 | /* Skip gaps. */ |
| 313 | if (bfun->errcode != 0) |
| 314 | continue; |
| 315 | |
| 316 | last = VEC_last (btrace_insn_s, bfun->insn); |
| 317 | |
| 318 | if (last->iclass == BTRACE_INSN_CALL) |
| 319 | break; |
| 320 | } |
| 321 | |
| 322 | return bfun; |
| 323 | } |
| 324 | |
| 325 | /* Add a continuation segment for a function into which we return. |
| 326 | PREV is the chronologically preceding function segment. |
| 327 | MFUN and FUN are the symbol information we have for this function. */ |
| 328 | |
| 329 | static struct btrace_function * |
| 330 | ftrace_new_return (struct btrace_function *prev, |
| 331 | struct minimal_symbol *mfun, |
| 332 | struct symbol *fun) |
| 333 | { |
| 334 | struct btrace_function *bfun, *caller; |
| 335 | |
| 336 | bfun = ftrace_new_function (prev, mfun, fun); |
| 337 | |
| 338 | /* It is important to start at PREV's caller. Otherwise, we might find |
| 339 | PREV itself, if PREV is a recursive function. */ |
| 340 | caller = ftrace_find_caller (prev->up, mfun, fun); |
| 341 | if (caller != NULL) |
| 342 | { |
| 343 | /* The caller of PREV is the preceding btrace function segment in this |
| 344 | function instance. */ |
| 345 | gdb_assert (caller->segment.next == NULL); |
| 346 | |
| 347 | caller->segment.next = bfun; |
| 348 | bfun->segment.prev = caller; |
| 349 | |
| 350 | /* Maintain the function level. */ |
| 351 | bfun->level = caller->level; |
| 352 | |
| 353 | /* Maintain the call stack. */ |
| 354 | bfun->up = caller->up; |
| 355 | bfun->flags = caller->flags; |
| 356 | |
| 357 | ftrace_debug (bfun, "new return"); |
| 358 | } |
| 359 | else |
| 360 | { |
| 361 | /* We did not find a caller. This could mean that something went |
| 362 | wrong or that the call is simply not included in the trace. */ |
| 363 | |
| 364 | /* Let's search for some actual call. */ |
| 365 | caller = ftrace_find_call (prev->up); |
| 366 | if (caller == NULL) |
| 367 | { |
| 368 | /* There is no call in PREV's back trace. We assume that the |
| 369 | branch trace did not include it. */ |
| 370 | |
| 371 | /* Let's find the topmost call function - this skips tail calls. */ |
| 372 | while (prev->up != NULL) |
| 373 | prev = prev->up; |
| 374 | |
| 375 | /* We maintain levels for a series of returns for which we have |
| 376 | not seen the calls. |
| 377 | We start at the preceding function's level in case this has |
| 378 | already been a return for which we have not seen the call. |
| 379 | We start at level 0 otherwise, to handle tail calls correctly. */ |
| 380 | bfun->level = min (0, prev->level) - 1; |
| 381 | |
| 382 | /* Fix up the call stack for PREV. */ |
| 383 | ftrace_fixup_caller (prev, bfun, BFUN_UP_LINKS_TO_RET); |
| 384 | |
| 385 | ftrace_debug (bfun, "new return - no caller"); |
| 386 | } |
| 387 | else |
| 388 | { |
| 389 | /* There is a call in PREV's back trace to which we should have |
| 390 | returned. Let's remain at this level. */ |
| 391 | bfun->level = prev->level; |
| 392 | |
| 393 | ftrace_debug (bfun, "new return - unknown caller"); |
| 394 | } |
| 395 | } |
| 396 | |
| 397 | return bfun; |
| 398 | } |
| 399 | |
| 400 | /* Add a new function segment for a function switch. |
| 401 | PREV is the chronologically preceding function segment. |
| 402 | MFUN and FUN are the symbol information we have for this function. */ |
| 403 | |
| 404 | static struct btrace_function * |
| 405 | ftrace_new_switch (struct btrace_function *prev, |
| 406 | struct minimal_symbol *mfun, |
| 407 | struct symbol *fun) |
| 408 | { |
| 409 | struct btrace_function *bfun; |
| 410 | |
| 411 | /* This is an unexplained function switch. The call stack will likely |
| 412 | be wrong at this point. */ |
| 413 | bfun = ftrace_new_function (prev, mfun, fun); |
| 414 | |
| 415 | ftrace_debug (bfun, "new switch"); |
| 416 | |
| 417 | return bfun; |
| 418 | } |
| 419 | |
| 420 | /* Add a new function segment for a gap in the trace due to a decode error. |
| 421 | PREV is the chronologically preceding function segment. |
| 422 | ERRCODE is the format-specific error code. */ |
| 423 | |
| 424 | static struct btrace_function * |
| 425 | ftrace_new_gap (struct btrace_function *prev, int errcode) |
| 426 | { |
| 427 | struct btrace_function *bfun; |
| 428 | |
| 429 | /* We hijack prev if it was empty. */ |
| 430 | if (prev != NULL && prev->errcode == 0 |
| 431 | && VEC_empty (btrace_insn_s, prev->insn)) |
| 432 | bfun = prev; |
| 433 | else |
| 434 | bfun = ftrace_new_function (prev, NULL, NULL); |
| 435 | |
| 436 | bfun->errcode = errcode; |
| 437 | |
| 438 | ftrace_debug (bfun, "new gap"); |
| 439 | |
| 440 | return bfun; |
| 441 | } |
| 442 | |
| 443 | /* Update BFUN with respect to the instruction at PC. This may create new |
| 444 | function segments. |
| 445 | Return the chronologically latest function segment, never NULL. */ |
| 446 | |
| 447 | static struct btrace_function * |
| 448 | ftrace_update_function (struct btrace_function *bfun, CORE_ADDR pc) |
| 449 | { |
| 450 | struct bound_minimal_symbol bmfun; |
| 451 | struct minimal_symbol *mfun; |
| 452 | struct symbol *fun; |
| 453 | struct btrace_insn *last; |
| 454 | |
| 455 | /* Try to determine the function we're in. We use both types of symbols |
| 456 | to avoid surprises when we sometimes get a full symbol and sometimes |
| 457 | only a minimal symbol. */ |
| 458 | fun = find_pc_function (pc); |
| 459 | bmfun = lookup_minimal_symbol_by_pc (pc); |
| 460 | mfun = bmfun.minsym; |
| 461 | |
| 462 | if (fun == NULL && mfun == NULL) |
| 463 | DEBUG_FTRACE ("no symbol at %s", core_addr_to_string_nz (pc)); |
| 464 | |
| 465 | /* If we didn't have a function or if we had a gap before, we create one. */ |
| 466 | if (bfun == NULL || bfun->errcode != 0) |
| 467 | return ftrace_new_function (bfun, mfun, fun); |
| 468 | |
| 469 | /* Check the last instruction, if we have one. |
| 470 | We do this check first, since it allows us to fill in the call stack |
| 471 | links in addition to the normal flow links. */ |
| 472 | last = NULL; |
| 473 | if (!VEC_empty (btrace_insn_s, bfun->insn)) |
| 474 | last = VEC_last (btrace_insn_s, bfun->insn); |
| 475 | |
| 476 | if (last != NULL) |
| 477 | { |
| 478 | switch (last->iclass) |
| 479 | { |
| 480 | case BTRACE_INSN_RETURN: |
| 481 | { |
| 482 | const char *fname; |
| 483 | |
| 484 | /* On some systems, _dl_runtime_resolve returns to the resolved |
| 485 | function instead of jumping to it. From our perspective, |
| 486 | however, this is a tailcall. |
| 487 | If we treated it as return, we wouldn't be able to find the |
| 488 | resolved function in our stack back trace. Hence, we would |
| 489 | lose the current stack back trace and start anew with an empty |
| 490 | back trace. When the resolved function returns, we would then |
| 491 | create a stack back trace with the same function names but |
| 492 | different frame id's. This will confuse stepping. */ |
| 493 | fname = ftrace_print_function_name (bfun); |
| 494 | if (strcmp (fname, "_dl_runtime_resolve") == 0) |
| 495 | return ftrace_new_tailcall (bfun, mfun, fun); |
| 496 | |
| 497 | return ftrace_new_return (bfun, mfun, fun); |
| 498 | } |
| 499 | |
| 500 | case BTRACE_INSN_CALL: |
| 501 | /* Ignore calls to the next instruction. They are used for PIC. */ |
| 502 | if (last->pc + last->size == pc) |
| 503 | break; |
| 504 | |
| 505 | return ftrace_new_call (bfun, mfun, fun); |
| 506 | |
| 507 | case BTRACE_INSN_JUMP: |
| 508 | { |
| 509 | CORE_ADDR start; |
| 510 | |
| 511 | start = get_pc_function_start (pc); |
| 512 | |
| 513 | /* If we can't determine the function for PC, we treat a jump at |
| 514 | the end of the block as tail call. */ |
| 515 | if (start == 0 || start == pc) |
| 516 | return ftrace_new_tailcall (bfun, mfun, fun); |
| 517 | } |
| 518 | } |
| 519 | } |
| 520 | |
| 521 | /* Check if we're switching functions for some other reason. */ |
| 522 | if (ftrace_function_switched (bfun, mfun, fun)) |
| 523 | { |
| 524 | DEBUG_FTRACE ("switching from %s in %s at %s", |
| 525 | ftrace_print_insn_addr (last), |
| 526 | ftrace_print_function_name (bfun), |
| 527 | ftrace_print_filename (bfun)); |
| 528 | |
| 529 | return ftrace_new_switch (bfun, mfun, fun); |
| 530 | } |
| 531 | |
| 532 | return bfun; |
| 533 | } |
| 534 | |
| 535 | /* Add the instruction at PC to BFUN's instructions. */ |
| 536 | |
| 537 | static void |
| 538 | ftrace_update_insns (struct btrace_function *bfun, |
| 539 | const struct btrace_insn *insn) |
| 540 | { |
| 541 | VEC_safe_push (btrace_insn_s, bfun->insn, insn); |
| 542 | |
| 543 | if (record_debug > 1) |
| 544 | ftrace_debug (bfun, "update insn"); |
| 545 | } |
| 546 | |
| 547 | /* Classify the instruction at PC. */ |
| 548 | |
| 549 | static enum btrace_insn_class |
| 550 | ftrace_classify_insn (struct gdbarch *gdbarch, CORE_ADDR pc) |
| 551 | { |
| 552 | enum btrace_insn_class iclass; |
| 553 | |
| 554 | iclass = BTRACE_INSN_OTHER; |
| 555 | TRY |
| 556 | { |
| 557 | if (gdbarch_insn_is_call (gdbarch, pc)) |
| 558 | iclass = BTRACE_INSN_CALL; |
| 559 | else if (gdbarch_insn_is_ret (gdbarch, pc)) |
| 560 | iclass = BTRACE_INSN_RETURN; |
| 561 | else if (gdbarch_insn_is_jump (gdbarch, pc)) |
| 562 | iclass = BTRACE_INSN_JUMP; |
| 563 | } |
| 564 | CATCH (error, RETURN_MASK_ERROR) |
| 565 | { |
| 566 | } |
| 567 | END_CATCH |
| 568 | |
| 569 | return iclass; |
| 570 | } |
| 571 | |
| 572 | /* Compute the function branch trace from BTS trace. */ |
| 573 | |
| 574 | static void |
| 575 | btrace_compute_ftrace_bts (struct thread_info *tp, |
| 576 | const struct btrace_data_bts *btrace) |
| 577 | { |
| 578 | struct btrace_thread_info *btinfo; |
| 579 | struct btrace_function *begin, *end; |
| 580 | struct gdbarch *gdbarch; |
| 581 | unsigned int blk, ngaps; |
| 582 | int level; |
| 583 | |
| 584 | gdbarch = target_gdbarch (); |
| 585 | btinfo = &tp->btrace; |
| 586 | begin = btinfo->begin; |
| 587 | end = btinfo->end; |
| 588 | ngaps = btinfo->ngaps; |
| 589 | level = begin != NULL ? -btinfo->level : INT_MAX; |
| 590 | blk = VEC_length (btrace_block_s, btrace->blocks); |
| 591 | |
| 592 | while (blk != 0) |
| 593 | { |
| 594 | btrace_block_s *block; |
| 595 | CORE_ADDR pc; |
| 596 | |
| 597 | blk -= 1; |
| 598 | |
| 599 | block = VEC_index (btrace_block_s, btrace->blocks, blk); |
| 600 | pc = block->begin; |
| 601 | |
| 602 | for (;;) |
| 603 | { |
| 604 | struct btrace_insn insn; |
| 605 | int size; |
| 606 | |
| 607 | /* We should hit the end of the block. Warn if we went too far. */ |
| 608 | if (block->end < pc) |
| 609 | { |
| 610 | /* Indicate the gap in the trace - unless we're at the |
| 611 | beginning. */ |
| 612 | if (begin != NULL) |
| 613 | { |
| 614 | warning (_("Recorded trace may be corrupted around %s."), |
| 615 | core_addr_to_string_nz (pc)); |
| 616 | |
| 617 | end = ftrace_new_gap (end, BDE_BTS_OVERFLOW); |
| 618 | ngaps += 1; |
| 619 | } |
| 620 | break; |
| 621 | } |
| 622 | |
| 623 | end = ftrace_update_function (end, pc); |
| 624 | if (begin == NULL) |
| 625 | begin = end; |
| 626 | |
| 627 | /* Maintain the function level offset. |
| 628 | For all but the last block, we do it here. */ |
| 629 | if (blk != 0) |
| 630 | level = min (level, end->level); |
| 631 | |
| 632 | size = 0; |
| 633 | TRY |
| 634 | { |
| 635 | size = gdb_insn_length (gdbarch, pc); |
| 636 | } |
| 637 | CATCH (error, RETURN_MASK_ERROR) |
| 638 | { |
| 639 | } |
| 640 | END_CATCH |
| 641 | |
| 642 | insn.pc = pc; |
| 643 | insn.size = size; |
| 644 | insn.iclass = ftrace_classify_insn (gdbarch, pc); |
| 645 | |
| 646 | ftrace_update_insns (end, &insn); |
| 647 | |
| 648 | /* We're done once we pushed the instruction at the end. */ |
| 649 | if (block->end == pc) |
| 650 | break; |
| 651 | |
| 652 | /* We can't continue if we fail to compute the size. */ |
| 653 | if (size <= 0) |
| 654 | { |
| 655 | warning (_("Recorded trace may be incomplete around %s."), |
| 656 | core_addr_to_string_nz (pc)); |
| 657 | |
| 658 | /* Indicate the gap in the trace. We just added INSN so we're |
| 659 | not at the beginning. */ |
| 660 | end = ftrace_new_gap (end, BDE_BTS_INSN_SIZE); |
| 661 | ngaps += 1; |
| 662 | |
| 663 | break; |
| 664 | } |
| 665 | |
| 666 | pc += size; |
| 667 | |
| 668 | /* Maintain the function level offset. |
| 669 | For the last block, we do it here to not consider the last |
| 670 | instruction. |
| 671 | Since the last instruction corresponds to the current instruction |
| 672 | and is not really part of the execution history, it shouldn't |
| 673 | affect the level. */ |
| 674 | if (blk == 0) |
| 675 | level = min (level, end->level); |
| 676 | } |
| 677 | } |
| 678 | |
| 679 | btinfo->begin = begin; |
| 680 | btinfo->end = end; |
| 681 | btinfo->ngaps = ngaps; |
| 682 | |
| 683 | /* LEVEL is the minimal function level of all btrace function segments. |
| 684 | Define the global level offset to -LEVEL so all function levels are |
| 685 | normalized to start at zero. */ |
| 686 | btinfo->level = -level; |
| 687 | } |
| 688 | |
| 689 | /* Compute the function branch trace from a block branch trace BTRACE for |
| 690 | a thread given by BTINFO. */ |
| 691 | |
| 692 | static void |
| 693 | btrace_compute_ftrace (struct thread_info *tp, struct btrace_data *btrace) |
| 694 | { |
| 695 | DEBUG ("compute ftrace"); |
| 696 | |
| 697 | switch (btrace->format) |
| 698 | { |
| 699 | case BTRACE_FORMAT_NONE: |
| 700 | return; |
| 701 | |
| 702 | case BTRACE_FORMAT_BTS: |
| 703 | btrace_compute_ftrace_bts (tp, &btrace->variant.bts); |
| 704 | return; |
| 705 | } |
| 706 | |
| 707 | internal_error (__FILE__, __LINE__, _("Unkown branch trace format.")); |
| 708 | } |
| 709 | |
| 710 | /* Add an entry for the current PC. */ |
| 711 | |
| 712 | static void |
| 713 | btrace_add_pc (struct thread_info *tp) |
| 714 | { |
| 715 | struct btrace_data btrace; |
| 716 | struct btrace_block *block; |
| 717 | struct regcache *regcache; |
| 718 | struct cleanup *cleanup; |
| 719 | CORE_ADDR pc; |
| 720 | |
| 721 | regcache = get_thread_regcache (tp->ptid); |
| 722 | pc = regcache_read_pc (regcache); |
| 723 | |
| 724 | btrace_data_init (&btrace); |
| 725 | btrace.format = BTRACE_FORMAT_BTS; |
| 726 | btrace.variant.bts.blocks = NULL; |
| 727 | |
| 728 | cleanup = make_cleanup_btrace_data (&btrace); |
| 729 | |
| 730 | block = VEC_safe_push (btrace_block_s, btrace.variant.bts.blocks, NULL); |
| 731 | block->begin = pc; |
| 732 | block->end = pc; |
| 733 | |
| 734 | btrace_compute_ftrace (tp, &btrace); |
| 735 | |
| 736 | do_cleanups (cleanup); |
| 737 | } |
| 738 | |
| 739 | /* See btrace.h. */ |
| 740 | |
| 741 | void |
| 742 | btrace_enable (struct thread_info *tp, const struct btrace_config *conf) |
| 743 | { |
| 744 | if (tp->btrace.target != NULL) |
| 745 | return; |
| 746 | |
| 747 | if (!target_supports_btrace (conf->format)) |
| 748 | error (_("Target does not support branch tracing.")); |
| 749 | |
| 750 | DEBUG ("enable thread %d (%s)", tp->num, target_pid_to_str (tp->ptid)); |
| 751 | |
| 752 | tp->btrace.target = target_enable_btrace (tp->ptid, conf); |
| 753 | |
| 754 | /* Add an entry for the current PC so we start tracing from where we |
| 755 | enabled it. */ |
| 756 | if (tp->btrace.target != NULL) |
| 757 | btrace_add_pc (tp); |
| 758 | } |
| 759 | |
| 760 | /* See btrace.h. */ |
| 761 | |
| 762 | const struct btrace_config * |
| 763 | btrace_conf (const struct btrace_thread_info *btinfo) |
| 764 | { |
| 765 | if (btinfo->target == NULL) |
| 766 | return NULL; |
| 767 | |
| 768 | return target_btrace_conf (btinfo->target); |
| 769 | } |
| 770 | |
| 771 | /* See btrace.h. */ |
| 772 | |
| 773 | void |
| 774 | btrace_disable (struct thread_info *tp) |
| 775 | { |
| 776 | struct btrace_thread_info *btp = &tp->btrace; |
| 777 | int errcode = 0; |
| 778 | |
| 779 | if (btp->target == NULL) |
| 780 | return; |
| 781 | |
| 782 | DEBUG ("disable thread %d (%s)", tp->num, target_pid_to_str (tp->ptid)); |
| 783 | |
| 784 | target_disable_btrace (btp->target); |
| 785 | btp->target = NULL; |
| 786 | |
| 787 | btrace_clear (tp); |
| 788 | } |
| 789 | |
| 790 | /* See btrace.h. */ |
| 791 | |
| 792 | void |
| 793 | btrace_teardown (struct thread_info *tp) |
| 794 | { |
| 795 | struct btrace_thread_info *btp = &tp->btrace; |
| 796 | int errcode = 0; |
| 797 | |
| 798 | if (btp->target == NULL) |
| 799 | return; |
| 800 | |
| 801 | DEBUG ("teardown thread %d (%s)", tp->num, target_pid_to_str (tp->ptid)); |
| 802 | |
| 803 | target_teardown_btrace (btp->target); |
| 804 | btp->target = NULL; |
| 805 | |
| 806 | btrace_clear (tp); |
| 807 | } |
| 808 | |
| 809 | /* Stitch branch trace in BTS format. */ |
| 810 | |
| 811 | static int |
| 812 | btrace_stitch_bts (struct btrace_data_bts *btrace, struct thread_info *tp) |
| 813 | { |
| 814 | struct btrace_thread_info *btinfo; |
| 815 | struct btrace_function *last_bfun; |
| 816 | struct btrace_insn *last_insn; |
| 817 | btrace_block_s *first_new_block; |
| 818 | |
| 819 | btinfo = &tp->btrace; |
| 820 | last_bfun = btinfo->end; |
| 821 | gdb_assert (last_bfun != NULL); |
| 822 | gdb_assert (!VEC_empty (btrace_block_s, btrace->blocks)); |
| 823 | |
| 824 | /* If the existing trace ends with a gap, we just glue the traces |
| 825 | together. We need to drop the last (i.e. chronologically first) block |
| 826 | of the new trace, though, since we can't fill in the start address.*/ |
| 827 | if (VEC_empty (btrace_insn_s, last_bfun->insn)) |
| 828 | { |
| 829 | VEC_pop (btrace_block_s, btrace->blocks); |
| 830 | return 0; |
| 831 | } |
| 832 | |
| 833 | /* Beware that block trace starts with the most recent block, so the |
| 834 | chronologically first block in the new trace is the last block in |
| 835 | the new trace's block vector. */ |
| 836 | first_new_block = VEC_last (btrace_block_s, btrace->blocks); |
| 837 | last_insn = VEC_last (btrace_insn_s, last_bfun->insn); |
| 838 | |
| 839 | /* If the current PC at the end of the block is the same as in our current |
| 840 | trace, there are two explanations: |
| 841 | 1. we executed the instruction and some branch brought us back. |
| 842 | 2. we have not made any progress. |
| 843 | In the first case, the delta trace vector should contain at least two |
| 844 | entries. |
| 845 | In the second case, the delta trace vector should contain exactly one |
| 846 | entry for the partial block containing the current PC. Remove it. */ |
| 847 | if (first_new_block->end == last_insn->pc |
| 848 | && VEC_length (btrace_block_s, btrace->blocks) == 1) |
| 849 | { |
| 850 | VEC_pop (btrace_block_s, btrace->blocks); |
| 851 | return 0; |
| 852 | } |
| 853 | |
| 854 | DEBUG ("stitching %s to %s", ftrace_print_insn_addr (last_insn), |
| 855 | core_addr_to_string_nz (first_new_block->end)); |
| 856 | |
| 857 | /* Do a simple sanity check to make sure we don't accidentally end up |
| 858 | with a bad block. This should not occur in practice. */ |
| 859 | if (first_new_block->end < last_insn->pc) |
| 860 | { |
| 861 | warning (_("Error while trying to read delta trace. Falling back to " |
| 862 | "a full read.")); |
| 863 | return -1; |
| 864 | } |
| 865 | |
| 866 | /* We adjust the last block to start at the end of our current trace. */ |
| 867 | gdb_assert (first_new_block->begin == 0); |
| 868 | first_new_block->begin = last_insn->pc; |
| 869 | |
| 870 | /* We simply pop the last insn so we can insert it again as part of |
| 871 | the normal branch trace computation. |
| 872 | Since instruction iterators are based on indices in the instructions |
| 873 | vector, we don't leave any pointers dangling. */ |
| 874 | DEBUG ("pruning insn at %s for stitching", |
| 875 | ftrace_print_insn_addr (last_insn)); |
| 876 | |
| 877 | VEC_pop (btrace_insn_s, last_bfun->insn); |
| 878 | |
| 879 | /* The instructions vector may become empty temporarily if this has |
| 880 | been the only instruction in this function segment. |
| 881 | This violates the invariant but will be remedied shortly by |
| 882 | btrace_compute_ftrace when we add the new trace. */ |
| 883 | |
| 884 | /* The only case where this would hurt is if the entire trace consisted |
| 885 | of just that one instruction. If we remove it, we might turn the now |
| 886 | empty btrace function segment into a gap. But we don't want gaps at |
| 887 | the beginning. To avoid this, we remove the entire old trace. */ |
| 888 | if (last_bfun == btinfo->begin && VEC_empty (btrace_insn_s, last_bfun->insn)) |
| 889 | btrace_clear (tp); |
| 890 | |
| 891 | return 0; |
| 892 | } |
| 893 | |
| 894 | /* Adjust the block trace in order to stitch old and new trace together. |
| 895 | BTRACE is the new delta trace between the last and the current stop. |
| 896 | TP is the traced thread. |
| 897 | May modifx BTRACE as well as the existing trace in TP. |
| 898 | Return 0 on success, -1 otherwise. */ |
| 899 | |
| 900 | static int |
| 901 | btrace_stitch_trace (struct btrace_data *btrace, struct thread_info *tp) |
| 902 | { |
| 903 | /* If we don't have trace, there's nothing to do. */ |
| 904 | if (btrace_data_empty (btrace)) |
| 905 | return 0; |
| 906 | |
| 907 | switch (btrace->format) |
| 908 | { |
| 909 | case BTRACE_FORMAT_NONE: |
| 910 | return 0; |
| 911 | |
| 912 | case BTRACE_FORMAT_BTS: |
| 913 | return btrace_stitch_bts (&btrace->variant.bts, tp); |
| 914 | } |
| 915 | |
| 916 | internal_error (__FILE__, __LINE__, _("Unkown branch trace format.")); |
| 917 | } |
| 918 | |
| 919 | /* Clear the branch trace histories in BTINFO. */ |
| 920 | |
| 921 | static void |
| 922 | btrace_clear_history (struct btrace_thread_info *btinfo) |
| 923 | { |
| 924 | xfree (btinfo->insn_history); |
| 925 | xfree (btinfo->call_history); |
| 926 | xfree (btinfo->replay); |
| 927 | |
| 928 | btinfo->insn_history = NULL; |
| 929 | btinfo->call_history = NULL; |
| 930 | btinfo->replay = NULL; |
| 931 | } |
| 932 | |
| 933 | /* See btrace.h. */ |
| 934 | |
| 935 | void |
| 936 | btrace_fetch (struct thread_info *tp) |
| 937 | { |
| 938 | struct btrace_thread_info *btinfo; |
| 939 | struct btrace_target_info *tinfo; |
| 940 | struct btrace_data btrace; |
| 941 | struct cleanup *cleanup; |
| 942 | int errcode; |
| 943 | |
| 944 | DEBUG ("fetch thread %d (%s)", tp->num, target_pid_to_str (tp->ptid)); |
| 945 | |
| 946 | btinfo = &tp->btrace; |
| 947 | tinfo = btinfo->target; |
| 948 | if (tinfo == NULL) |
| 949 | return; |
| 950 | |
| 951 | /* There's no way we could get new trace while replaying. |
| 952 | On the other hand, delta trace would return a partial record with the |
| 953 | current PC, which is the replay PC, not the last PC, as expected. */ |
| 954 | if (btinfo->replay != NULL) |
| 955 | return; |
| 956 | |
| 957 | btrace_data_init (&btrace); |
| 958 | cleanup = make_cleanup_btrace_data (&btrace); |
| 959 | |
| 960 | /* Let's first try to extend the trace we already have. */ |
| 961 | if (btinfo->end != NULL) |
| 962 | { |
| 963 | errcode = target_read_btrace (&btrace, tinfo, BTRACE_READ_DELTA); |
| 964 | if (errcode == 0) |
| 965 | { |
| 966 | /* Success. Let's try to stitch the traces together. */ |
| 967 | errcode = btrace_stitch_trace (&btrace, tp); |
| 968 | } |
| 969 | else |
| 970 | { |
| 971 | /* We failed to read delta trace. Let's try to read new trace. */ |
| 972 | errcode = target_read_btrace (&btrace, tinfo, BTRACE_READ_NEW); |
| 973 | |
| 974 | /* If we got any new trace, discard what we have. */ |
| 975 | if (errcode == 0 && !btrace_data_empty (&btrace)) |
| 976 | btrace_clear (tp); |
| 977 | } |
| 978 | |
| 979 | /* If we were not able to read the trace, we start over. */ |
| 980 | if (errcode != 0) |
| 981 | { |
| 982 | btrace_clear (tp); |
| 983 | errcode = target_read_btrace (&btrace, tinfo, BTRACE_READ_ALL); |
| 984 | } |
| 985 | } |
| 986 | else |
| 987 | errcode = target_read_btrace (&btrace, tinfo, BTRACE_READ_ALL); |
| 988 | |
| 989 | /* If we were not able to read the branch trace, signal an error. */ |
| 990 | if (errcode != 0) |
| 991 | error (_("Failed to read branch trace.")); |
| 992 | |
| 993 | /* Compute the trace, provided we have any. */ |
| 994 | if (!btrace_data_empty (&btrace)) |
| 995 | { |
| 996 | btrace_clear_history (btinfo); |
| 997 | btrace_compute_ftrace (tp, &btrace); |
| 998 | } |
| 999 | |
| 1000 | do_cleanups (cleanup); |
| 1001 | } |
| 1002 | |
| 1003 | /* See btrace.h. */ |
| 1004 | |
| 1005 | void |
| 1006 | btrace_clear (struct thread_info *tp) |
| 1007 | { |
| 1008 | struct btrace_thread_info *btinfo; |
| 1009 | struct btrace_function *it, *trash; |
| 1010 | |
| 1011 | DEBUG ("clear thread %d (%s)", tp->num, target_pid_to_str (tp->ptid)); |
| 1012 | |
| 1013 | /* Make sure btrace frames that may hold a pointer into the branch |
| 1014 | trace data are destroyed. */ |
| 1015 | reinit_frame_cache (); |
| 1016 | |
| 1017 | btinfo = &tp->btrace; |
| 1018 | |
| 1019 | it = btinfo->begin; |
| 1020 | while (it != NULL) |
| 1021 | { |
| 1022 | trash = it; |
| 1023 | it = it->flow.next; |
| 1024 | |
| 1025 | xfree (trash); |
| 1026 | } |
| 1027 | |
| 1028 | btinfo->begin = NULL; |
| 1029 | btinfo->end = NULL; |
| 1030 | btinfo->ngaps = 0; |
| 1031 | |
| 1032 | btrace_clear_history (btinfo); |
| 1033 | } |
| 1034 | |
| 1035 | /* See btrace.h. */ |
| 1036 | |
| 1037 | void |
| 1038 | btrace_free_objfile (struct objfile *objfile) |
| 1039 | { |
| 1040 | struct thread_info *tp; |
| 1041 | |
| 1042 | DEBUG ("free objfile"); |
| 1043 | |
| 1044 | ALL_NON_EXITED_THREADS (tp) |
| 1045 | btrace_clear (tp); |
| 1046 | } |
| 1047 | |
| 1048 | #if defined (HAVE_LIBEXPAT) |
| 1049 | |
| 1050 | /* Check the btrace document version. */ |
| 1051 | |
| 1052 | static void |
| 1053 | check_xml_btrace_version (struct gdb_xml_parser *parser, |
| 1054 | const struct gdb_xml_element *element, |
| 1055 | void *user_data, VEC (gdb_xml_value_s) *attributes) |
| 1056 | { |
| 1057 | const char *version = xml_find_attribute (attributes, "version")->value; |
| 1058 | |
| 1059 | if (strcmp (version, "1.0") != 0) |
| 1060 | gdb_xml_error (parser, _("Unsupported btrace version: \"%s\""), version); |
| 1061 | } |
| 1062 | |
| 1063 | /* Parse a btrace "block" xml record. */ |
| 1064 | |
| 1065 | static void |
| 1066 | parse_xml_btrace_block (struct gdb_xml_parser *parser, |
| 1067 | const struct gdb_xml_element *element, |
| 1068 | void *user_data, VEC (gdb_xml_value_s) *attributes) |
| 1069 | { |
| 1070 | struct btrace_data *btrace; |
| 1071 | struct btrace_block *block; |
| 1072 | ULONGEST *begin, *end; |
| 1073 | |
| 1074 | btrace = user_data; |
| 1075 | |
| 1076 | switch (btrace->format) |
| 1077 | { |
| 1078 | case BTRACE_FORMAT_BTS: |
| 1079 | break; |
| 1080 | |
| 1081 | case BTRACE_FORMAT_NONE: |
| 1082 | btrace->format = BTRACE_FORMAT_BTS; |
| 1083 | btrace->variant.bts.blocks = NULL; |
| 1084 | break; |
| 1085 | |
| 1086 | default: |
| 1087 | gdb_xml_error (parser, _("Btrace format error.")); |
| 1088 | } |
| 1089 | |
| 1090 | begin = xml_find_attribute (attributes, "begin")->value; |
| 1091 | end = xml_find_attribute (attributes, "end")->value; |
| 1092 | |
| 1093 | block = VEC_safe_push (btrace_block_s, btrace->variant.bts.blocks, NULL); |
| 1094 | block->begin = *begin; |
| 1095 | block->end = *end; |
| 1096 | } |
| 1097 | |
| 1098 | static const struct gdb_xml_attribute block_attributes[] = { |
| 1099 | { "begin", GDB_XML_AF_NONE, gdb_xml_parse_attr_ulongest, NULL }, |
| 1100 | { "end", GDB_XML_AF_NONE, gdb_xml_parse_attr_ulongest, NULL }, |
| 1101 | { NULL, GDB_XML_AF_NONE, NULL, NULL } |
| 1102 | }; |
| 1103 | |
| 1104 | static const struct gdb_xml_attribute btrace_attributes[] = { |
| 1105 | { "version", GDB_XML_AF_NONE, NULL, NULL }, |
| 1106 | { NULL, GDB_XML_AF_NONE, NULL, NULL } |
| 1107 | }; |
| 1108 | |
| 1109 | static const struct gdb_xml_element btrace_children[] = { |
| 1110 | { "block", block_attributes, NULL, |
| 1111 | GDB_XML_EF_REPEATABLE | GDB_XML_EF_OPTIONAL, parse_xml_btrace_block, NULL }, |
| 1112 | { NULL, NULL, NULL, GDB_XML_EF_NONE, NULL, NULL } |
| 1113 | }; |
| 1114 | |
| 1115 | static const struct gdb_xml_element btrace_elements[] = { |
| 1116 | { "btrace", btrace_attributes, btrace_children, GDB_XML_EF_NONE, |
| 1117 | check_xml_btrace_version, NULL }, |
| 1118 | { NULL, NULL, NULL, GDB_XML_EF_NONE, NULL, NULL } |
| 1119 | }; |
| 1120 | |
| 1121 | #endif /* defined (HAVE_LIBEXPAT) */ |
| 1122 | |
| 1123 | /* See btrace.h. */ |
| 1124 | |
| 1125 | void |
| 1126 | parse_xml_btrace (struct btrace_data *btrace, const char *buffer) |
| 1127 | { |
| 1128 | struct cleanup *cleanup; |
| 1129 | int errcode; |
| 1130 | |
| 1131 | #if defined (HAVE_LIBEXPAT) |
| 1132 | |
| 1133 | btrace->format = BTRACE_FORMAT_NONE; |
| 1134 | |
| 1135 | cleanup = make_cleanup_btrace_data (btrace); |
| 1136 | errcode = gdb_xml_parse_quick (_("btrace"), "btrace.dtd", btrace_elements, |
| 1137 | buffer, btrace); |
| 1138 | if (errcode != 0) |
| 1139 | error (_("Error parsing branch trace.")); |
| 1140 | |
| 1141 | /* Keep parse results. */ |
| 1142 | discard_cleanups (cleanup); |
| 1143 | |
| 1144 | #else /* !defined (HAVE_LIBEXPAT) */ |
| 1145 | |
| 1146 | error (_("Cannot process branch trace. XML parsing is not supported.")); |
| 1147 | |
| 1148 | #endif /* !defined (HAVE_LIBEXPAT) */ |
| 1149 | } |
| 1150 | |
| 1151 | #if defined (HAVE_LIBEXPAT) |
| 1152 | |
| 1153 | /* Parse a btrace-conf "bts" xml record. */ |
| 1154 | |
| 1155 | static void |
| 1156 | parse_xml_btrace_conf_bts (struct gdb_xml_parser *parser, |
| 1157 | const struct gdb_xml_element *element, |
| 1158 | void *user_data, VEC (gdb_xml_value_s) *attributes) |
| 1159 | { |
| 1160 | struct btrace_config *conf; |
| 1161 | struct gdb_xml_value *size; |
| 1162 | |
| 1163 | conf = user_data; |
| 1164 | conf->format = BTRACE_FORMAT_BTS; |
| 1165 | conf->bts.size = 0; |
| 1166 | |
| 1167 | size = xml_find_attribute (attributes, "size"); |
| 1168 | if (size != NULL) |
| 1169 | conf->bts.size = (unsigned int) * (ULONGEST *) size->value; |
| 1170 | } |
| 1171 | |
| 1172 | static const struct gdb_xml_attribute btrace_conf_bts_attributes[] = { |
| 1173 | { "size", GDB_XML_AF_OPTIONAL, gdb_xml_parse_attr_ulongest, NULL }, |
| 1174 | { NULL, GDB_XML_AF_NONE, NULL, NULL } |
| 1175 | }; |
| 1176 | |
| 1177 | static const struct gdb_xml_element btrace_conf_children[] = { |
| 1178 | { "bts", btrace_conf_bts_attributes, NULL, GDB_XML_EF_OPTIONAL, |
| 1179 | parse_xml_btrace_conf_bts, NULL }, |
| 1180 | { NULL, NULL, NULL, GDB_XML_EF_NONE, NULL, NULL } |
| 1181 | }; |
| 1182 | |
| 1183 | static const struct gdb_xml_attribute btrace_conf_attributes[] = { |
| 1184 | { "version", GDB_XML_AF_NONE, NULL, NULL }, |
| 1185 | { NULL, GDB_XML_AF_NONE, NULL, NULL } |
| 1186 | }; |
| 1187 | |
| 1188 | static const struct gdb_xml_element btrace_conf_elements[] = { |
| 1189 | { "btrace-conf", btrace_conf_attributes, btrace_conf_children, |
| 1190 | GDB_XML_EF_NONE, NULL, NULL }, |
| 1191 | { NULL, NULL, NULL, GDB_XML_EF_NONE, NULL, NULL } |
| 1192 | }; |
| 1193 | |
| 1194 | #endif /* defined (HAVE_LIBEXPAT) */ |
| 1195 | |
| 1196 | /* See btrace.h. */ |
| 1197 | |
| 1198 | void |
| 1199 | parse_xml_btrace_conf (struct btrace_config *conf, const char *xml) |
| 1200 | { |
| 1201 | int errcode; |
| 1202 | |
| 1203 | #if defined (HAVE_LIBEXPAT) |
| 1204 | |
| 1205 | errcode = gdb_xml_parse_quick (_("btrace-conf"), "btrace-conf.dtd", |
| 1206 | btrace_conf_elements, xml, conf); |
| 1207 | if (errcode != 0) |
| 1208 | error (_("Error parsing branch trace configuration.")); |
| 1209 | |
| 1210 | #else /* !defined (HAVE_LIBEXPAT) */ |
| 1211 | |
| 1212 | error (_("XML parsing is not supported.")); |
| 1213 | |
| 1214 | #endif /* !defined (HAVE_LIBEXPAT) */ |
| 1215 | } |
| 1216 | |
| 1217 | /* See btrace.h. */ |
| 1218 | |
| 1219 | const struct btrace_insn * |
| 1220 | btrace_insn_get (const struct btrace_insn_iterator *it) |
| 1221 | { |
| 1222 | const struct btrace_function *bfun; |
| 1223 | unsigned int index, end; |
| 1224 | |
| 1225 | index = it->index; |
| 1226 | bfun = it->function; |
| 1227 | |
| 1228 | /* Check if the iterator points to a gap in the trace. */ |
| 1229 | if (bfun->errcode != 0) |
| 1230 | return NULL; |
| 1231 | |
| 1232 | /* The index is within the bounds of this function's instruction vector. */ |
| 1233 | end = VEC_length (btrace_insn_s, bfun->insn); |
| 1234 | gdb_assert (0 < end); |
| 1235 | gdb_assert (index < end); |
| 1236 | |
| 1237 | return VEC_index (btrace_insn_s, bfun->insn, index); |
| 1238 | } |
| 1239 | |
| 1240 | /* See btrace.h. */ |
| 1241 | |
| 1242 | unsigned int |
| 1243 | btrace_insn_number (const struct btrace_insn_iterator *it) |
| 1244 | { |
| 1245 | const struct btrace_function *bfun; |
| 1246 | |
| 1247 | bfun = it->function; |
| 1248 | |
| 1249 | /* Return zero if the iterator points to a gap in the trace. */ |
| 1250 | if (bfun->errcode != 0) |
| 1251 | return 0; |
| 1252 | |
| 1253 | return bfun->insn_offset + it->index; |
| 1254 | } |
| 1255 | |
| 1256 | /* See btrace.h. */ |
| 1257 | |
| 1258 | void |
| 1259 | btrace_insn_begin (struct btrace_insn_iterator *it, |
| 1260 | const struct btrace_thread_info *btinfo) |
| 1261 | { |
| 1262 | const struct btrace_function *bfun; |
| 1263 | |
| 1264 | bfun = btinfo->begin; |
| 1265 | if (bfun == NULL) |
| 1266 | error (_("No trace.")); |
| 1267 | |
| 1268 | it->function = bfun; |
| 1269 | it->index = 0; |
| 1270 | } |
| 1271 | |
| 1272 | /* See btrace.h. */ |
| 1273 | |
| 1274 | void |
| 1275 | btrace_insn_end (struct btrace_insn_iterator *it, |
| 1276 | const struct btrace_thread_info *btinfo) |
| 1277 | { |
| 1278 | const struct btrace_function *bfun; |
| 1279 | unsigned int length; |
| 1280 | |
| 1281 | bfun = btinfo->end; |
| 1282 | if (bfun == NULL) |
| 1283 | error (_("No trace.")); |
| 1284 | |
| 1285 | length = VEC_length (btrace_insn_s, bfun->insn); |
| 1286 | |
| 1287 | /* The last function may either be a gap or it contains the current |
| 1288 | instruction, which is one past the end of the execution trace; ignore |
| 1289 | it. */ |
| 1290 | if (length > 0) |
| 1291 | length -= 1; |
| 1292 | |
| 1293 | it->function = bfun; |
| 1294 | it->index = length; |
| 1295 | } |
| 1296 | |
| 1297 | /* See btrace.h. */ |
| 1298 | |
| 1299 | unsigned int |
| 1300 | btrace_insn_next (struct btrace_insn_iterator *it, unsigned int stride) |
| 1301 | { |
| 1302 | const struct btrace_function *bfun; |
| 1303 | unsigned int index, steps; |
| 1304 | |
| 1305 | bfun = it->function; |
| 1306 | steps = 0; |
| 1307 | index = it->index; |
| 1308 | |
| 1309 | while (stride != 0) |
| 1310 | { |
| 1311 | unsigned int end, space, adv; |
| 1312 | |
| 1313 | end = VEC_length (btrace_insn_s, bfun->insn); |
| 1314 | |
| 1315 | /* An empty function segment represents a gap in the trace. We count |
| 1316 | it as one instruction. */ |
| 1317 | if (end == 0) |
| 1318 | { |
| 1319 | const struct btrace_function *next; |
| 1320 | |
| 1321 | next = bfun->flow.next; |
| 1322 | if (next == NULL) |
| 1323 | break; |
| 1324 | |
| 1325 | stride -= 1; |
| 1326 | steps += 1; |
| 1327 | |
| 1328 | bfun = next; |
| 1329 | index = 0; |
| 1330 | |
| 1331 | continue; |
| 1332 | } |
| 1333 | |
| 1334 | gdb_assert (0 < end); |
| 1335 | gdb_assert (index < end); |
| 1336 | |
| 1337 | /* Compute the number of instructions remaining in this segment. */ |
| 1338 | space = end - index; |
| 1339 | |
| 1340 | /* Advance the iterator as far as possible within this segment. */ |
| 1341 | adv = min (space, stride); |
| 1342 | stride -= adv; |
| 1343 | index += adv; |
| 1344 | steps += adv; |
| 1345 | |
| 1346 | /* Move to the next function if we're at the end of this one. */ |
| 1347 | if (index == end) |
| 1348 | { |
| 1349 | const struct btrace_function *next; |
| 1350 | |
| 1351 | next = bfun->flow.next; |
| 1352 | if (next == NULL) |
| 1353 | { |
| 1354 | /* We stepped past the last function. |
| 1355 | |
| 1356 | Let's adjust the index to point to the last instruction in |
| 1357 | the previous function. */ |
| 1358 | index -= 1; |
| 1359 | steps -= 1; |
| 1360 | break; |
| 1361 | } |
| 1362 | |
| 1363 | /* We now point to the first instruction in the new function. */ |
| 1364 | bfun = next; |
| 1365 | index = 0; |
| 1366 | } |
| 1367 | |
| 1368 | /* We did make progress. */ |
| 1369 | gdb_assert (adv > 0); |
| 1370 | } |
| 1371 | |
| 1372 | /* Update the iterator. */ |
| 1373 | it->function = bfun; |
| 1374 | it->index = index; |
| 1375 | |
| 1376 | return steps; |
| 1377 | } |
| 1378 | |
| 1379 | /* See btrace.h. */ |
| 1380 | |
| 1381 | unsigned int |
| 1382 | btrace_insn_prev (struct btrace_insn_iterator *it, unsigned int stride) |
| 1383 | { |
| 1384 | const struct btrace_function *bfun; |
| 1385 | unsigned int index, steps; |
| 1386 | |
| 1387 | bfun = it->function; |
| 1388 | steps = 0; |
| 1389 | index = it->index; |
| 1390 | |
| 1391 | while (stride != 0) |
| 1392 | { |
| 1393 | unsigned int adv; |
| 1394 | |
| 1395 | /* Move to the previous function if we're at the start of this one. */ |
| 1396 | if (index == 0) |
| 1397 | { |
| 1398 | const struct btrace_function *prev; |
| 1399 | |
| 1400 | prev = bfun->flow.prev; |
| 1401 | if (prev == NULL) |
| 1402 | break; |
| 1403 | |
| 1404 | /* We point to one after the last instruction in the new function. */ |
| 1405 | bfun = prev; |
| 1406 | index = VEC_length (btrace_insn_s, bfun->insn); |
| 1407 | |
| 1408 | /* An empty function segment represents a gap in the trace. We count |
| 1409 | it as one instruction. */ |
| 1410 | if (index == 0) |
| 1411 | { |
| 1412 | stride -= 1; |
| 1413 | steps += 1; |
| 1414 | |
| 1415 | continue; |
| 1416 | } |
| 1417 | } |
| 1418 | |
| 1419 | /* Advance the iterator as far as possible within this segment. */ |
| 1420 | adv = min (index, stride); |
| 1421 | |
| 1422 | stride -= adv; |
| 1423 | index -= adv; |
| 1424 | steps += adv; |
| 1425 | |
| 1426 | /* We did make progress. */ |
| 1427 | gdb_assert (adv > 0); |
| 1428 | } |
| 1429 | |
| 1430 | /* Update the iterator. */ |
| 1431 | it->function = bfun; |
| 1432 | it->index = index; |
| 1433 | |
| 1434 | return steps; |
| 1435 | } |
| 1436 | |
| 1437 | /* See btrace.h. */ |
| 1438 | |
| 1439 | int |
| 1440 | btrace_insn_cmp (const struct btrace_insn_iterator *lhs, |
| 1441 | const struct btrace_insn_iterator *rhs) |
| 1442 | { |
| 1443 | unsigned int lnum, rnum; |
| 1444 | |
| 1445 | lnum = btrace_insn_number (lhs); |
| 1446 | rnum = btrace_insn_number (rhs); |
| 1447 | |
| 1448 | /* A gap has an instruction number of zero. Things are getting more |
| 1449 | complicated if gaps are involved. |
| 1450 | |
| 1451 | We take the instruction number offset from the iterator's function. |
| 1452 | This is the number of the first instruction after the gap. |
| 1453 | |
| 1454 | This is OK as long as both lhs and rhs point to gaps. If only one of |
| 1455 | them does, we need to adjust the number based on the other's regular |
| 1456 | instruction number. Otherwise, a gap might compare equal to an |
| 1457 | instruction. */ |
| 1458 | |
| 1459 | if (lnum == 0 && rnum == 0) |
| 1460 | { |
| 1461 | lnum = lhs->function->insn_offset; |
| 1462 | rnum = rhs->function->insn_offset; |
| 1463 | } |
| 1464 | else if (lnum == 0) |
| 1465 | { |
| 1466 | lnum = lhs->function->insn_offset; |
| 1467 | |
| 1468 | if (lnum == rnum) |
| 1469 | lnum -= 1; |
| 1470 | } |
| 1471 | else if (rnum == 0) |
| 1472 | { |
| 1473 | rnum = rhs->function->insn_offset; |
| 1474 | |
| 1475 | if (rnum == lnum) |
| 1476 | rnum -= 1; |
| 1477 | } |
| 1478 | |
| 1479 | return (int) (lnum - rnum); |
| 1480 | } |
| 1481 | |
| 1482 | /* See btrace.h. */ |
| 1483 | |
| 1484 | int |
| 1485 | btrace_find_insn_by_number (struct btrace_insn_iterator *it, |
| 1486 | const struct btrace_thread_info *btinfo, |
| 1487 | unsigned int number) |
| 1488 | { |
| 1489 | const struct btrace_function *bfun; |
| 1490 | unsigned int end, length; |
| 1491 | |
| 1492 | for (bfun = btinfo->end; bfun != NULL; bfun = bfun->flow.prev) |
| 1493 | { |
| 1494 | /* Skip gaps. */ |
| 1495 | if (bfun->errcode != 0) |
| 1496 | continue; |
| 1497 | |
| 1498 | if (bfun->insn_offset <= number) |
| 1499 | break; |
| 1500 | } |
| 1501 | |
| 1502 | if (bfun == NULL) |
| 1503 | return 0; |
| 1504 | |
| 1505 | length = VEC_length (btrace_insn_s, bfun->insn); |
| 1506 | gdb_assert (length > 0); |
| 1507 | |
| 1508 | end = bfun->insn_offset + length; |
| 1509 | if (end <= number) |
| 1510 | return 0; |
| 1511 | |
| 1512 | it->function = bfun; |
| 1513 | it->index = number - bfun->insn_offset; |
| 1514 | |
| 1515 | return 1; |
| 1516 | } |
| 1517 | |
| 1518 | /* See btrace.h. */ |
| 1519 | |
| 1520 | const struct btrace_function * |
| 1521 | btrace_call_get (const struct btrace_call_iterator *it) |
| 1522 | { |
| 1523 | return it->function; |
| 1524 | } |
| 1525 | |
| 1526 | /* See btrace.h. */ |
| 1527 | |
| 1528 | unsigned int |
| 1529 | btrace_call_number (const struct btrace_call_iterator *it) |
| 1530 | { |
| 1531 | const struct btrace_thread_info *btinfo; |
| 1532 | const struct btrace_function *bfun; |
| 1533 | unsigned int insns; |
| 1534 | |
| 1535 | btinfo = it->btinfo; |
| 1536 | bfun = it->function; |
| 1537 | if (bfun != NULL) |
| 1538 | return bfun->number; |
| 1539 | |
| 1540 | /* For the end iterator, i.e. bfun == NULL, we return one more than the |
| 1541 | number of the last function. */ |
| 1542 | bfun = btinfo->end; |
| 1543 | insns = VEC_length (btrace_insn_s, bfun->insn); |
| 1544 | |
| 1545 | /* If the function contains only a single instruction (i.e. the current |
| 1546 | instruction), it will be skipped and its number is already the number |
| 1547 | we seek. */ |
| 1548 | if (insns == 1) |
| 1549 | return bfun->number; |
| 1550 | |
| 1551 | /* Otherwise, return one more than the number of the last function. */ |
| 1552 | return bfun->number + 1; |
| 1553 | } |
| 1554 | |
| 1555 | /* See btrace.h. */ |
| 1556 | |
| 1557 | void |
| 1558 | btrace_call_begin (struct btrace_call_iterator *it, |
| 1559 | const struct btrace_thread_info *btinfo) |
| 1560 | { |
| 1561 | const struct btrace_function *bfun; |
| 1562 | |
| 1563 | bfun = btinfo->begin; |
| 1564 | if (bfun == NULL) |
| 1565 | error (_("No trace.")); |
| 1566 | |
| 1567 | it->btinfo = btinfo; |
| 1568 | it->function = bfun; |
| 1569 | } |
| 1570 | |
| 1571 | /* See btrace.h. */ |
| 1572 | |
| 1573 | void |
| 1574 | btrace_call_end (struct btrace_call_iterator *it, |
| 1575 | const struct btrace_thread_info *btinfo) |
| 1576 | { |
| 1577 | const struct btrace_function *bfun; |
| 1578 | |
| 1579 | bfun = btinfo->end; |
| 1580 | if (bfun == NULL) |
| 1581 | error (_("No trace.")); |
| 1582 | |
| 1583 | it->btinfo = btinfo; |
| 1584 | it->function = NULL; |
| 1585 | } |
| 1586 | |
| 1587 | /* See btrace.h. */ |
| 1588 | |
| 1589 | unsigned int |
| 1590 | btrace_call_next (struct btrace_call_iterator *it, unsigned int stride) |
| 1591 | { |
| 1592 | const struct btrace_function *bfun; |
| 1593 | unsigned int steps; |
| 1594 | |
| 1595 | bfun = it->function; |
| 1596 | steps = 0; |
| 1597 | while (bfun != NULL) |
| 1598 | { |
| 1599 | const struct btrace_function *next; |
| 1600 | unsigned int insns; |
| 1601 | |
| 1602 | next = bfun->flow.next; |
| 1603 | if (next == NULL) |
| 1604 | { |
| 1605 | /* Ignore the last function if it only contains a single |
| 1606 | (i.e. the current) instruction. */ |
| 1607 | insns = VEC_length (btrace_insn_s, bfun->insn); |
| 1608 | if (insns == 1) |
| 1609 | steps -= 1; |
| 1610 | } |
| 1611 | |
| 1612 | if (stride == steps) |
| 1613 | break; |
| 1614 | |
| 1615 | bfun = next; |
| 1616 | steps += 1; |
| 1617 | } |
| 1618 | |
| 1619 | it->function = bfun; |
| 1620 | return steps; |
| 1621 | } |
| 1622 | |
| 1623 | /* See btrace.h. */ |
| 1624 | |
| 1625 | unsigned int |
| 1626 | btrace_call_prev (struct btrace_call_iterator *it, unsigned int stride) |
| 1627 | { |
| 1628 | const struct btrace_thread_info *btinfo; |
| 1629 | const struct btrace_function *bfun; |
| 1630 | unsigned int steps; |
| 1631 | |
| 1632 | bfun = it->function; |
| 1633 | steps = 0; |
| 1634 | |
| 1635 | if (bfun == NULL) |
| 1636 | { |
| 1637 | unsigned int insns; |
| 1638 | |
| 1639 | btinfo = it->btinfo; |
| 1640 | bfun = btinfo->end; |
| 1641 | if (bfun == NULL) |
| 1642 | return 0; |
| 1643 | |
| 1644 | /* Ignore the last function if it only contains a single |
| 1645 | (i.e. the current) instruction. */ |
| 1646 | insns = VEC_length (btrace_insn_s, bfun->insn); |
| 1647 | if (insns == 1) |
| 1648 | bfun = bfun->flow.prev; |
| 1649 | |
| 1650 | if (bfun == NULL) |
| 1651 | return 0; |
| 1652 | |
| 1653 | steps += 1; |
| 1654 | } |
| 1655 | |
| 1656 | while (steps < stride) |
| 1657 | { |
| 1658 | const struct btrace_function *prev; |
| 1659 | |
| 1660 | prev = bfun->flow.prev; |
| 1661 | if (prev == NULL) |
| 1662 | break; |
| 1663 | |
| 1664 | bfun = prev; |
| 1665 | steps += 1; |
| 1666 | } |
| 1667 | |
| 1668 | it->function = bfun; |
| 1669 | return steps; |
| 1670 | } |
| 1671 | |
| 1672 | /* See btrace.h. */ |
| 1673 | |
| 1674 | int |
| 1675 | btrace_call_cmp (const struct btrace_call_iterator *lhs, |
| 1676 | const struct btrace_call_iterator *rhs) |
| 1677 | { |
| 1678 | unsigned int lnum, rnum; |
| 1679 | |
| 1680 | lnum = btrace_call_number (lhs); |
| 1681 | rnum = btrace_call_number (rhs); |
| 1682 | |
| 1683 | return (int) (lnum - rnum); |
| 1684 | } |
| 1685 | |
| 1686 | /* See btrace.h. */ |
| 1687 | |
| 1688 | int |
| 1689 | btrace_find_call_by_number (struct btrace_call_iterator *it, |
| 1690 | const struct btrace_thread_info *btinfo, |
| 1691 | unsigned int number) |
| 1692 | { |
| 1693 | const struct btrace_function *bfun; |
| 1694 | |
| 1695 | for (bfun = btinfo->end; bfun != NULL; bfun = bfun->flow.prev) |
| 1696 | { |
| 1697 | unsigned int bnum; |
| 1698 | |
| 1699 | bnum = bfun->number; |
| 1700 | if (number == bnum) |
| 1701 | { |
| 1702 | it->btinfo = btinfo; |
| 1703 | it->function = bfun; |
| 1704 | return 1; |
| 1705 | } |
| 1706 | |
| 1707 | /* Functions are ordered and numbered consecutively. We could bail out |
| 1708 | earlier. On the other hand, it is very unlikely that we search for |
| 1709 | a nonexistent function. */ |
| 1710 | } |
| 1711 | |
| 1712 | return 0; |
| 1713 | } |
| 1714 | |
| 1715 | /* See btrace.h. */ |
| 1716 | |
| 1717 | void |
| 1718 | btrace_set_insn_history (struct btrace_thread_info *btinfo, |
| 1719 | const struct btrace_insn_iterator *begin, |
| 1720 | const struct btrace_insn_iterator *end) |
| 1721 | { |
| 1722 | if (btinfo->insn_history == NULL) |
| 1723 | btinfo->insn_history = xzalloc (sizeof (*btinfo->insn_history)); |
| 1724 | |
| 1725 | btinfo->insn_history->begin = *begin; |
| 1726 | btinfo->insn_history->end = *end; |
| 1727 | } |
| 1728 | |
| 1729 | /* See btrace.h. */ |
| 1730 | |
| 1731 | void |
| 1732 | btrace_set_call_history (struct btrace_thread_info *btinfo, |
| 1733 | const struct btrace_call_iterator *begin, |
| 1734 | const struct btrace_call_iterator *end) |
| 1735 | { |
| 1736 | gdb_assert (begin->btinfo == end->btinfo); |
| 1737 | |
| 1738 | if (btinfo->call_history == NULL) |
| 1739 | btinfo->call_history = xzalloc (sizeof (*btinfo->call_history)); |
| 1740 | |
| 1741 | btinfo->call_history->begin = *begin; |
| 1742 | btinfo->call_history->end = *end; |
| 1743 | } |
| 1744 | |
| 1745 | /* See btrace.h. */ |
| 1746 | |
| 1747 | int |
| 1748 | btrace_is_replaying (struct thread_info *tp) |
| 1749 | { |
| 1750 | return tp->btrace.replay != NULL; |
| 1751 | } |
| 1752 | |
| 1753 | /* See btrace.h. */ |
| 1754 | |
| 1755 | int |
| 1756 | btrace_is_empty (struct thread_info *tp) |
| 1757 | { |
| 1758 | struct btrace_insn_iterator begin, end; |
| 1759 | struct btrace_thread_info *btinfo; |
| 1760 | |
| 1761 | btinfo = &tp->btrace; |
| 1762 | |
| 1763 | if (btinfo->begin == NULL) |
| 1764 | return 1; |
| 1765 | |
| 1766 | btrace_insn_begin (&begin, btinfo); |
| 1767 | btrace_insn_end (&end, btinfo); |
| 1768 | |
| 1769 | return btrace_insn_cmp (&begin, &end) == 0; |
| 1770 | } |
| 1771 | |
| 1772 | /* Forward the cleanup request. */ |
| 1773 | |
| 1774 | static void |
| 1775 | do_btrace_data_cleanup (void *arg) |
| 1776 | { |
| 1777 | btrace_data_fini (arg); |
| 1778 | } |
| 1779 | |
| 1780 | /* See btrace.h. */ |
| 1781 | |
| 1782 | struct cleanup * |
| 1783 | make_cleanup_btrace_data (struct btrace_data *data) |
| 1784 | { |
| 1785 | return make_cleanup (do_btrace_data_cleanup, data); |
| 1786 | } |