1 /* Branch trace support for GDB, the GNU debugger.
3 Copyright (C) 2013-2014 Free Software Foundation, Inc.
5 Contributed by Intel Corp. <markus.t.metzger@intel.com>
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 "gdbthread.h"
24 #include "exceptions.h"
31 #include "filenames.h"
32 #include "xml-support.h"
34 /* Print a record debug message. Use do ... while (0) to avoid ambiguities
35 when used in if statements. */
37 #define DEBUG(msg, args...) \
40 if (record_debug != 0) \
41 fprintf_unfiltered (gdb_stdlog, \
42 "[btrace] " msg "\n", ##args); \
46 #define DEBUG_FTRACE(msg, args...) DEBUG ("[ftrace] " msg, ##args)
48 /* Initialize the instruction iterator. */
51 btrace_init_insn_iterator (struct btrace_thread_info *btinfo)
53 DEBUG ("init insn iterator");
55 btinfo->insn_iterator.begin = 1;
56 btinfo->insn_iterator.end = 0;
59 /* Initialize the function iterator. */
62 btrace_init_func_iterator (struct btrace_thread_info *btinfo)
64 DEBUG ("init func iterator");
66 btinfo->func_iterator.begin = 1;
67 btinfo->func_iterator.end = 0;
70 /* Compute the instruction trace from the block trace. */
72 static VEC (btrace_inst_s) *
73 compute_itrace (VEC (btrace_block_s) *btrace)
75 VEC (btrace_inst_s) *itrace;
76 struct gdbarch *gdbarch;
79 DEBUG ("compute itrace");
82 gdbarch = target_gdbarch ();
83 b = VEC_length (btrace_block_s, btrace);
87 btrace_block_s *block;
90 block = VEC_index (btrace_block_s, btrace, b);
93 /* Add instructions for this block. */
99 /* We should hit the end of the block. Warn if we went too far. */
102 warning (_("Recorded trace may be corrupted."));
106 inst = VEC_safe_push (btrace_inst_s, itrace, NULL);
109 /* We're done once we pushed the instruction at the end. */
110 if (block->end == pc)
113 size = gdb_insn_length (gdbarch, pc);
115 /* Make sure we terminate if we fail to compute the size. */
118 warning (_("Recorded trace may be incomplete."));
129 /* Return the function name of a recorded function segment for printing.
130 This function never returns NULL. */
133 ftrace_print_function_name (struct btrace_func *bfun)
135 struct minimal_symbol *msym;
142 return SYMBOL_PRINT_NAME (sym);
145 return SYMBOL_PRINT_NAME (msym);
150 /* Return the file name of a recorded function segment for printing.
151 This function never returns NULL. */
154 ftrace_print_filename (struct btrace_func *bfun)
157 const char *filename;
162 filename = symtab_to_filename_for_display (sym->symtab);
164 filename = "<unknown>";
169 /* Print an ftrace debug status message. */
172 ftrace_debug (struct btrace_func *bfun, const char *prefix)
174 DEBUG_FTRACE ("%s: fun = %s, file = %s, lines = [%d; %d], insn = [%u; %u]",
175 prefix, ftrace_print_function_name (bfun),
176 ftrace_print_filename (bfun), bfun->lbegin, bfun->lend,
177 bfun->ibegin, bfun->iend);
180 /* Initialize a recorded function segment. */
183 ftrace_init_func (struct btrace_func *bfun, struct minimal_symbol *mfun,
184 struct symbol *fun, unsigned int idx)
188 bfun->lbegin = INT_MAX;
194 /* Check whether the function has changed. */
197 ftrace_function_switched (struct btrace_func *bfun,
198 struct minimal_symbol *mfun, struct symbol *fun)
200 struct minimal_symbol *msym;
203 /* The function changed if we did not have one before. */
210 /* If the minimal symbol changed, we certainly switched functions. */
211 if (mfun != NULL && msym != NULL
212 && strcmp (SYMBOL_LINKAGE_NAME (mfun), SYMBOL_LINKAGE_NAME (msym)) != 0)
215 /* If the symbol changed, we certainly switched functions. */
216 if (fun != NULL && sym != NULL)
218 const char *bfname, *fname;
220 /* Check the function name. */
221 if (strcmp (SYMBOL_LINKAGE_NAME (fun), SYMBOL_LINKAGE_NAME (sym)) != 0)
224 /* Check the location of those functions, as well. */
225 bfname = symtab_to_fullname (sym->symtab);
226 fname = symtab_to_fullname (fun->symtab);
227 if (filename_cmp (fname, bfname) != 0)
234 /* Check if we should skip this file when generating the function call
235 history. We would want to do that if, say, a macro that is defined
236 in another file is expanded in this function. */
239 ftrace_skip_file (struct btrace_func *bfun, const char *filename)
247 bfile = symtab_to_fullname (sym->symtab);
251 if (filename == NULL)
254 return (filename_cmp (bfile, filename) != 0);
257 /* Compute the function trace from the instruction trace. */
259 static VEC (btrace_func_s) *
260 compute_ftrace (VEC (btrace_inst_s) *itrace)
262 VEC (btrace_func_s) *ftrace;
263 struct btrace_inst *binst;
264 struct btrace_func *bfun;
267 DEBUG ("compute ftrace");
272 for (idx = 0; VEC_iterate (btrace_inst_s, itrace, idx, binst); ++idx)
274 struct symtab_and_line sal;
275 struct bound_minimal_symbol mfun;
277 const char *filename;
282 /* Try to determine the function we're in. We use both types of symbols
283 to avoid surprises when we sometimes get a full symbol and sometimes
284 only a minimal symbol. */
285 fun = find_pc_function (pc);
286 mfun = lookup_minimal_symbol_by_pc (pc);
288 if (fun == NULL && mfun.minsym == NULL)
290 DEBUG_FTRACE ("no symbol at %u, pc=%s", idx,
291 core_addr_to_string_nz (pc));
295 /* If we're switching functions, we start over. */
296 if (ftrace_function_switched (bfun, mfun.minsym, fun))
298 bfun = VEC_safe_push (btrace_func_s, ftrace, NULL);
300 ftrace_init_func (bfun, mfun.minsym, fun, idx);
301 ftrace_debug (bfun, "init");
304 /* Update the instruction range. */
306 ftrace_debug (bfun, "update insns");
308 /* Let's see if we have source correlation, as well. */
309 sal = find_pc_line (pc, 0);
310 if (sal.symtab == NULL || sal.line == 0)
312 DEBUG_FTRACE ("no lines at %u, pc=%s", idx,
313 core_addr_to_string_nz (pc));
317 /* Check if we switched files. This could happen if, say, a macro that
318 is defined in another file is expanded here. */
319 filename = symtab_to_fullname (sal.symtab);
320 if (ftrace_skip_file (bfun, filename))
322 DEBUG_FTRACE ("ignoring file at %u, pc=%s, file=%s", idx,
323 core_addr_to_string_nz (pc), filename);
327 /* Update the line range. */
328 bfun->lbegin = min (bfun->lbegin, sal.line);
329 bfun->lend = max (bfun->lend, sal.line);
330 ftrace_debug (bfun, "update lines");
339 btrace_enable (struct thread_info *tp)
341 if (tp->btrace.target != NULL)
344 if (!target_supports_btrace ())
345 error (_("Target does not support branch tracing."));
347 DEBUG ("enable thread %d (%s)", tp->num, target_pid_to_str (tp->ptid));
349 tp->btrace.target = target_enable_btrace (tp->ptid);
355 btrace_disable (struct thread_info *tp)
357 struct btrace_thread_info *btp = &tp->btrace;
360 if (btp->target == NULL)
363 DEBUG ("disable thread %d (%s)", tp->num, target_pid_to_str (tp->ptid));
365 target_disable_btrace (btp->target);
374 btrace_teardown (struct thread_info *tp)
376 struct btrace_thread_info *btp = &tp->btrace;
379 if (btp->target == NULL)
382 DEBUG ("teardown thread %d (%s)", tp->num, target_pid_to_str (tp->ptid));
384 target_teardown_btrace (btp->target);
393 btrace_fetch (struct thread_info *tp)
395 struct btrace_thread_info *btinfo;
396 VEC (btrace_block_s) *btrace;
398 DEBUG ("fetch thread %d (%s)", tp->num, target_pid_to_str (tp->ptid));
400 btinfo = &tp->btrace;
401 if (btinfo->target == NULL)
404 btrace = target_read_btrace (btinfo->target, BTRACE_READ_NEW);
405 if (VEC_empty (btrace_block_s, btrace))
410 btinfo->btrace = btrace;
411 btinfo->itrace = compute_itrace (btinfo->btrace);
412 btinfo->ftrace = compute_ftrace (btinfo->itrace);
414 /* Initialize branch trace iterators. */
415 btrace_init_insn_iterator (btinfo);
416 btrace_init_func_iterator (btinfo);
422 btrace_clear (struct thread_info *tp)
424 struct btrace_thread_info *btinfo;
426 DEBUG ("clear thread %d (%s)", tp->num, target_pid_to_str (tp->ptid));
428 btinfo = &tp->btrace;
430 VEC_free (btrace_block_s, btinfo->btrace);
431 VEC_free (btrace_inst_s, btinfo->itrace);
432 VEC_free (btrace_func_s, btinfo->ftrace);
434 btinfo->btrace = NULL;
435 btinfo->itrace = NULL;
436 btinfo->ftrace = NULL;
442 btrace_free_objfile (struct objfile *objfile)
444 struct thread_info *tp;
446 DEBUG ("free objfile");
452 #if defined (HAVE_LIBEXPAT)
454 /* Check the btrace document version. */
457 check_xml_btrace_version (struct gdb_xml_parser *parser,
458 const struct gdb_xml_element *element,
459 void *user_data, VEC (gdb_xml_value_s) *attributes)
461 const char *version = xml_find_attribute (attributes, "version")->value;
463 if (strcmp (version, "1.0") != 0)
464 gdb_xml_error (parser, _("Unsupported btrace version: \"%s\""), version);
467 /* Parse a btrace "block" xml record. */
470 parse_xml_btrace_block (struct gdb_xml_parser *parser,
471 const struct gdb_xml_element *element,
472 void *user_data, VEC (gdb_xml_value_s) *attributes)
474 VEC (btrace_block_s) **btrace;
475 struct btrace_block *block;
476 ULONGEST *begin, *end;
479 block = VEC_safe_push (btrace_block_s, *btrace, NULL);
481 begin = xml_find_attribute (attributes, "begin")->value;
482 end = xml_find_attribute (attributes, "end")->value;
484 block->begin = *begin;
488 static const struct gdb_xml_attribute block_attributes[] = {
489 { "begin", GDB_XML_AF_NONE, gdb_xml_parse_attr_ulongest, NULL },
490 { "end", GDB_XML_AF_NONE, gdb_xml_parse_attr_ulongest, NULL },
491 { NULL, GDB_XML_AF_NONE, NULL, NULL }
494 static const struct gdb_xml_attribute btrace_attributes[] = {
495 { "version", GDB_XML_AF_NONE, NULL, NULL },
496 { NULL, GDB_XML_AF_NONE, NULL, NULL }
499 static const struct gdb_xml_element btrace_children[] = {
500 { "block", block_attributes, NULL,
501 GDB_XML_EF_REPEATABLE | GDB_XML_EF_OPTIONAL, parse_xml_btrace_block, NULL },
502 { NULL, NULL, NULL, GDB_XML_EF_NONE, NULL, NULL }
505 static const struct gdb_xml_element btrace_elements[] = {
506 { "btrace", btrace_attributes, btrace_children, GDB_XML_EF_NONE,
507 check_xml_btrace_version, NULL },
508 { NULL, NULL, NULL, GDB_XML_EF_NONE, NULL, NULL }
511 #endif /* defined (HAVE_LIBEXPAT) */
515 VEC (btrace_block_s) *
516 parse_xml_btrace (const char *buffer)
518 VEC (btrace_block_s) *btrace = NULL;
519 struct cleanup *cleanup;
522 #if defined (HAVE_LIBEXPAT)
524 cleanup = make_cleanup (VEC_cleanup (btrace_block_s), &btrace);
525 errcode = gdb_xml_parse_quick (_("btrace"), "btrace.dtd", btrace_elements,
529 do_cleanups (cleanup);
533 /* Keep parse results. */
534 discard_cleanups (cleanup);
536 #else /* !defined (HAVE_LIBEXPAT) */
538 error (_("Cannot process branch trace. XML parsing is not supported."));
540 #endif /* !defined (HAVE_LIBEXPAT) */