/* Branch trace support for GDB, the GNU debugger.
- Copyright (C) 2013-2014 Free Software Foundation, Inc.
+ Copyright (C) 2013-2015 Free Software Foundation, Inc.
Contributed by Intel Corp. <markus.t.metzger@intel.com>
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>. */
+#include "defs.h"
#include "btrace.h"
#include "gdbthread.h"
-#include "exceptions.h"
#include "inferior.h"
#include "target.h"
#include "record.h"
return SYMBOL_PRINT_NAME (sym);
if (msym != NULL)
- return SYMBOL_PRINT_NAME (msym);
+ return MSYMBOL_PRINT_NAME (msym);
return "<unknown>";
}
sym = bfun->sym;
if (sym != NULL)
- filename = symtab_to_filename_for_display (sym->symtab);
+ filename = symtab_to_filename_for_display (symbol_symtab (sym));
else
filename = "<unknown>";
/* If the minimal symbol changed, we certainly switched functions. */
if (mfun != NULL && msym != NULL
- && strcmp (SYMBOL_LINKAGE_NAME (mfun), SYMBOL_LINKAGE_NAME (msym)) != 0)
+ && strcmp (MSYMBOL_LINKAGE_NAME (mfun), MSYMBOL_LINKAGE_NAME (msym)) != 0)
return 1;
/* If the symbol changed, we certainly switched functions. */
return 1;
/* Check the location of those functions, as well. */
- bfname = symtab_to_fullname (sym->symtab);
- fname = symtab_to_fullname (fun->symtab);
+ bfname = symtab_to_fullname (symbol_symtab (sym));
+ fname = symtab_to_fullname (symbol_symtab (fun));
if (filename_cmp (fname, bfname) != 0)
return 1;
}
if (sym == NULL)
return 1;
- bfile = symtab_to_fullname (sym->symtab);
+ bfile = symtab_to_fullname (symbol_symtab (sym));
return (filename_cmp (bfile, fullname) != 0);
}
bfun->number = prev->number + 1;
bfun->insn_offset = (prev->insn_offset
+ VEC_length (btrace_insn_s, prev->insn));
+ bfun->level = prev->level;
}
return bfun;
bfun = ftrace_new_function (caller, mfun, fun);
bfun->up = caller;
- bfun->level = caller->level + 1;
+ bfun->level += 1;
ftrace_debug (bfun, "new call");
bfun = ftrace_new_function (caller, mfun, fun);
bfun->up = caller;
- bfun->level = caller->level + 1;
+ bfun->level += 1;
bfun->flags |= BFUN_UP_LINKS_TO_TAILCALL;
ftrace_debug (bfun, "new tail call");
tail calls ending with a jump). */
static struct btrace_function *
-ftrace_find_call (struct gdbarch *gdbarch, struct btrace_function *bfun)
+ftrace_find_call (struct btrace_function *bfun)
{
for (; bfun != NULL; bfun = bfun->up)
{
struct btrace_insn *last;
- CORE_ADDR pc;
- /* We do not allow empty function segments. */
- gdb_assert (!VEC_empty (btrace_insn_s, bfun->insn));
+ /* Skip gaps. */
+ if (bfun->errcode != 0)
+ continue;
last = VEC_last (btrace_insn_s, bfun->insn);
- pc = last->pc;
- if (gdbarch_insn_is_call (gdbarch, pc))
+ if (last->iclass == BTRACE_INSN_CALL)
break;
}
MFUN and FUN are the symbol information we have for this function. */
static struct btrace_function *
-ftrace_new_return (struct gdbarch *gdbarch,
- struct btrace_function *prev,
+ftrace_new_return (struct btrace_function *prev,
struct minimal_symbol *mfun,
struct symbol *fun)
{
wrong or that the call is simply not included in the trace. */
/* Let's search for some actual call. */
- caller = ftrace_find_call (gdbarch, prev->up);
+ caller = ftrace_find_call (prev->up);
if (caller == NULL)
{
/* There is no call in PREV's back trace. We assume that the
be wrong at this point. */
bfun = ftrace_new_function (prev, mfun, fun);
- /* We keep the function level. */
- bfun->level = prev->level;
-
ftrace_debug (bfun, "new switch");
return bfun;
}
+/* Add a new function segment for a gap in the trace due to a decode error.
+ PREV is the chronologically preceding function segment.
+ ERRCODE is the format-specific error code. */
+
+static struct btrace_function *
+ftrace_new_gap (struct btrace_function *prev, int errcode)
+{
+ struct btrace_function *bfun;
+
+ /* We hijack prev if it was empty. */
+ if (prev != NULL && prev->errcode == 0
+ && VEC_empty (btrace_insn_s, prev->insn))
+ bfun = prev;
+ else
+ bfun = ftrace_new_function (prev, NULL, NULL);
+
+ bfun->errcode = errcode;
+
+ ftrace_debug (bfun, "new gap");
+
+ return bfun;
+}
+
/* Update BFUN with respect to the instruction at PC. This may create new
function segments.
Return the chronologically latest function segment, never NULL. */
static struct btrace_function *
-ftrace_update_function (struct gdbarch *gdbarch,
- struct btrace_function *bfun, CORE_ADDR pc)
+ftrace_update_function (struct btrace_function *bfun, CORE_ADDR pc)
{
struct bound_minimal_symbol bmfun;
struct minimal_symbol *mfun;
if (fun == NULL && mfun == NULL)
DEBUG_FTRACE ("no symbol at %s", core_addr_to_string_nz (pc));
- /* If we didn't have a function before, we create one. */
- if (bfun == NULL)
+ /* If we didn't have a function or if we had a gap before, we create one. */
+ if (bfun == NULL || bfun->errcode != 0)
return ftrace_new_function (bfun, mfun, fun);
/* Check the last instruction, if we have one.
if (last != NULL)
{
- CORE_ADDR lpc;
+ switch (last->iclass)
+ {
+ case BTRACE_INSN_RETURN:
+ return ftrace_new_return (bfun, mfun, fun);
- lpc = last->pc;
+ case BTRACE_INSN_CALL:
+ /* Ignore calls to the next instruction. They are used for PIC. */
+ if (last->pc + last->size == pc)
+ break;
- /* Check for returns. */
- if (gdbarch_insn_is_ret (gdbarch, lpc))
- return ftrace_new_return (gdbarch, bfun, mfun, fun);
+ return ftrace_new_call (bfun, mfun, fun);
- /* Check for calls. */
- if (gdbarch_insn_is_call (gdbarch, lpc))
- {
- int size;
+ case BTRACE_INSN_JUMP:
+ {
+ CORE_ADDR start;
- size = gdb_insn_length (gdbarch, lpc);
+ start = get_pc_function_start (pc);
- /* Ignore calls to the next instruction. They are used for PIC. */
- if (lpc + size != pc)
- return ftrace_new_call (bfun, mfun, fun);
+ /* If we can't determine the function for PC, we treat a jump at
+ the end of the block as tail call. */
+ if (start == 0 || start == pc)
+ return ftrace_new_tailcall (bfun, mfun, fun);
+ }
}
}
ftrace_print_function_name (bfun),
ftrace_print_filename (bfun));
- if (last != NULL)
- {
- CORE_ADDR start, lpc;
-
- start = get_pc_function_start (pc);
-
- /* If we can't determine the function for PC, we treat a jump at
- the end of the block as tail call. */
- if (start == 0)
- start = pc;
-
- lpc = last->pc;
-
- /* Jumps indicate optimized tail calls. */
- if (start == pc && gdbarch_insn_is_jump (gdbarch, lpc))
- return ftrace_new_tailcall (bfun, mfun, fun);
- }
-
return ftrace_new_switch (bfun, mfun, fun);
}
/* Add the instruction at PC to BFUN's instructions. */
static void
-ftrace_update_insns (struct btrace_function *bfun, CORE_ADDR pc)
+ftrace_update_insns (struct btrace_function *bfun,
+ const struct btrace_insn *insn)
{
- struct btrace_insn *insn;
-
- insn = VEC_safe_push (btrace_insn_s, bfun->insn, NULL);
- insn->pc = pc;
+ VEC_safe_push (btrace_insn_s, bfun->insn, insn);
if (record_debug > 1)
ftrace_debug (bfun, "update insn");
}
-/* Compute the function branch trace from a block branch trace BTRACE for
- a thread given by BTINFO. */
+/* Classify the instruction at PC. */
+
+static enum btrace_insn_class
+ftrace_classify_insn (struct gdbarch *gdbarch, CORE_ADDR pc)
+{
+ volatile struct gdb_exception error;
+ enum btrace_insn_class iclass;
+
+ iclass = BTRACE_INSN_OTHER;
+ TRY_CATCH (error, RETURN_MASK_ERROR)
+ {
+ if (gdbarch_insn_is_call (gdbarch, pc))
+ iclass = BTRACE_INSN_CALL;
+ else if (gdbarch_insn_is_ret (gdbarch, pc))
+ iclass = BTRACE_INSN_RETURN;
+ else if (gdbarch_insn_is_jump (gdbarch, pc))
+ iclass = BTRACE_INSN_JUMP;
+ }
+
+ return iclass;
+}
+
+/* Compute the function branch trace from BTS trace. */
static void
-btrace_compute_ftrace (struct btrace_thread_info *btinfo,
- VEC (btrace_block_s) *btrace)
+btrace_compute_ftrace_bts (struct thread_info *tp,
+ const struct btrace_data_bts *btrace)
{
+ struct btrace_thread_info *btinfo;
struct btrace_function *begin, *end;
struct gdbarch *gdbarch;
- unsigned int blk;
+ unsigned int blk, ngaps;
int level;
- DEBUG ("compute ftrace");
-
gdbarch = target_gdbarch ();
+ btinfo = &tp->btrace;
begin = btinfo->begin;
end = btinfo->end;
+ ngaps = btinfo->ngaps;
level = begin != NULL ? -btinfo->level : INT_MAX;
- blk = VEC_length (btrace_block_s, btrace);
+ blk = VEC_length (btrace_block_s, btrace->blocks);
while (blk != 0)
{
blk -= 1;
- block = VEC_index (btrace_block_s, btrace, blk);
+ block = VEC_index (btrace_block_s, btrace->blocks, blk);
pc = block->begin;
for (;;)
{
+ volatile struct gdb_exception error;
+ struct btrace_insn insn;
int size;
/* We should hit the end of the block. Warn if we went too far. */
if (block->end < pc)
{
- warning (_("Recorded trace may be corrupted around %s."),
- core_addr_to_string_nz (pc));
+ /* Indicate the gap in the trace - unless we're at the
+ beginning. */
+ if (begin != NULL)
+ {
+ warning (_("Recorded trace may be corrupted around %s."),
+ core_addr_to_string_nz (pc));
+
+ end = ftrace_new_gap (end, BDE_BTS_OVERFLOW);
+ ngaps += 1;
+ }
break;
}
- end = ftrace_update_function (gdbarch, end, pc);
+ end = ftrace_update_function (end, pc);
if (begin == NULL)
begin = end;
if (blk != 0)
level = min (level, end->level);
- ftrace_update_insns (end, pc);
+ size = 0;
+ TRY_CATCH (error, RETURN_MASK_ERROR)
+ size = gdb_insn_length (gdbarch, pc);
+
+ insn.pc = pc;
+ insn.size = size;
+ insn.iclass = ftrace_classify_insn (gdbarch, pc);
+
+ ftrace_update_insns (end, &insn);
ftrace_update_lines (end, pc);
/* We're done once we pushed the instruction at the end. */
if (block->end == pc)
break;
- size = gdb_insn_length (gdbarch, pc);
-
- /* Make sure we terminate if we fail to compute the size. */
+ /* We can't continue if we fail to compute the size. */
if (size <= 0)
{
warning (_("Recorded trace may be incomplete around %s."),
core_addr_to_string_nz (pc));
+
+ /* Indicate the gap in the trace. We just added INSN so we're
+ not at the beginning. */
+ end = ftrace_new_gap (end, BDE_BTS_INSN_SIZE);
+ ngaps += 1;
+
break;
}
btinfo->begin = begin;
btinfo->end = end;
+ btinfo->ngaps = ngaps;
/* LEVEL is the minimal function level of all btrace function segments.
Define the global level offset to -LEVEL so all function levels are
btinfo->level = -level;
}
+/* Compute the function branch trace from a block branch trace BTRACE for
+ a thread given by BTINFO. */
+
+static void
+btrace_compute_ftrace (struct thread_info *tp, struct btrace_data *btrace)
+{
+ DEBUG ("compute ftrace");
+
+ switch (btrace->format)
+ {
+ case BTRACE_FORMAT_NONE:
+ return;
+
+ case BTRACE_FORMAT_BTS:
+ btrace_compute_ftrace_bts (tp, &btrace->variant.bts);
+ return;
+ }
+
+ internal_error (__FILE__, __LINE__, _("Unkown branch trace format."));
+}
+
/* Add an entry for the current PC. */
static void
btrace_add_pc (struct thread_info *tp)
{
- VEC (btrace_block_s) *btrace;
+ struct btrace_data btrace;
struct btrace_block *block;
struct regcache *regcache;
struct cleanup *cleanup;
regcache = get_thread_regcache (tp->ptid);
pc = regcache_read_pc (regcache);
- btrace = NULL;
- cleanup = make_cleanup (VEC_cleanup (btrace_block_s), &btrace);
+ btrace_data_init (&btrace);
+ btrace.format = BTRACE_FORMAT_BTS;
+ btrace.variant.bts.blocks = NULL;
+
+ cleanup = make_cleanup_btrace_data (&btrace);
- block = VEC_safe_push (btrace_block_s, btrace, NULL);
+ block = VEC_safe_push (btrace_block_s, btrace.variant.bts.blocks, NULL);
block->begin = pc;
block->end = pc;
- btrace_compute_ftrace (&tp->btrace, btrace);
+ btrace_compute_ftrace (tp, &btrace);
do_cleanups (cleanup);
}
/* See btrace.h. */
void
-btrace_enable (struct thread_info *tp)
+btrace_enable (struct thread_info *tp, const struct btrace_config *conf)
{
if (tp->btrace.target != NULL)
return;
- if (!target_supports_btrace ())
+ if (!target_supports_btrace (conf->format))
error (_("Target does not support branch tracing."));
DEBUG ("enable thread %d (%s)", tp->num, target_pid_to_str (tp->ptid));
- tp->btrace.target = target_enable_btrace (tp->ptid);
+ tp->btrace.target = target_enable_btrace (tp->ptid, conf);
/* Add an entry for the current PC so we start tracing from where we
enabled it. */
/* See btrace.h. */
+const struct btrace_config *
+btrace_conf (const struct btrace_thread_info *btinfo)
+{
+ if (btinfo->target == NULL)
+ return NULL;
+
+ return target_btrace_conf (btinfo->target);
+}
+
+/* See btrace.h. */
+
void
btrace_disable (struct thread_info *tp)
{
btrace_clear (tp);
}
-/* Adjust the block trace in order to stitch old and new trace together.
- BTRACE is the new delta trace between the last and the current stop.
- BTINFO is the old branch trace until the last stop.
- May modify BTRACE as well as the existing trace in BTINFO.
- Return 0 on success, -1 otherwise. */
+/* Stitch branch trace in BTS format. */
static int
-btrace_stitch_trace (VEC (btrace_block_s) **btrace,
- const struct btrace_thread_info *btinfo)
+btrace_stitch_bts (struct btrace_data_bts *btrace, struct thread_info *tp)
{
+ struct btrace_thread_info *btinfo;
struct btrace_function *last_bfun;
struct btrace_insn *last_insn;
btrace_block_s *first_new_block;
- /* If we don't have trace, there's nothing to do. */
- if (VEC_empty (btrace_block_s, *btrace))
- return 0;
-
+ btinfo = &tp->btrace;
last_bfun = btinfo->end;
gdb_assert (last_bfun != NULL);
+ gdb_assert (!VEC_empty (btrace_block_s, btrace->blocks));
+
+ /* If the existing trace ends with a gap, we just glue the traces
+ together. We need to drop the last (i.e. chronologically first) block
+ of the new trace, though, since we can't fill in the start address.*/
+ if (VEC_empty (btrace_insn_s, last_bfun->insn))
+ {
+ VEC_pop (btrace_block_s, btrace->blocks);
+ return 0;
+ }
/* Beware that block trace starts with the most recent block, so the
chronologically first block in the new trace is the last block in
the new trace's block vector. */
- first_new_block = VEC_last (btrace_block_s, *btrace);
+ first_new_block = VEC_last (btrace_block_s, btrace->blocks);
last_insn = VEC_last (btrace_insn_s, last_bfun->insn);
/* If the current PC at the end of the block is the same as in our current
In the second case, the delta trace vector should contain exactly one
entry for the partial block containing the current PC. Remove it. */
if (first_new_block->end == last_insn->pc
- && VEC_length (btrace_block_s, *btrace) == 1)
+ && VEC_length (btrace_block_s, btrace->blocks) == 1)
{
- VEC_pop (btrace_block_s, *btrace);
+ VEC_pop (btrace_block_s, btrace->blocks);
return 0;
}
been the only instruction in this function segment.
This violates the invariant but will be remedied shortly by
btrace_compute_ftrace when we add the new trace. */
+
+ /* The only case where this would hurt is if the entire trace consisted
+ of just that one instruction. If we remove it, we might turn the now
+ empty btrace function segment into a gap. But we don't want gaps at
+ the beginning. To avoid this, we remove the entire old trace. */
+ if (last_bfun == btinfo->begin && VEC_empty (btrace_insn_s, last_bfun->insn))
+ btrace_clear (tp);
+
return 0;
}
+/* Adjust the block trace in order to stitch old and new trace together.
+ BTRACE is the new delta trace between the last and the current stop.
+ TP is the traced thread.
+ May modifx BTRACE as well as the existing trace in TP.
+ Return 0 on success, -1 otherwise. */
+
+static int
+btrace_stitch_trace (struct btrace_data *btrace, struct thread_info *tp)
+{
+ /* If we don't have trace, there's nothing to do. */
+ if (btrace_data_empty (btrace))
+ return 0;
+
+ switch (btrace->format)
+ {
+ case BTRACE_FORMAT_NONE:
+ return 0;
+
+ case BTRACE_FORMAT_BTS:
+ return btrace_stitch_bts (&btrace->variant.bts, tp);
+ }
+
+ internal_error (__FILE__, __LINE__, _("Unkown branch trace format."));
+}
+
/* Clear the branch trace histories in BTINFO. */
static void
{
struct btrace_thread_info *btinfo;
struct btrace_target_info *tinfo;
- VEC (btrace_block_s) *btrace;
+ struct btrace_data btrace;
struct cleanup *cleanup;
int errcode;
DEBUG ("fetch thread %d (%s)", tp->num, target_pid_to_str (tp->ptid));
- btrace = NULL;
btinfo = &tp->btrace;
tinfo = btinfo->target;
if (tinfo == NULL)
if (btinfo->replay != NULL)
return;
- cleanup = make_cleanup (VEC_cleanup (btrace_block_s), &btrace);
+ btrace_data_init (&btrace);
+ cleanup = make_cleanup_btrace_data (&btrace);
/* Let's first try to extend the trace we already have. */
if (btinfo->end != NULL)
if (errcode == 0)
{
/* Success. Let's try to stitch the traces together. */
- errcode = btrace_stitch_trace (&btrace, btinfo);
+ errcode = btrace_stitch_trace (&btrace, tp);
}
else
{
errcode = target_read_btrace (&btrace, tinfo, BTRACE_READ_NEW);
/* If we got any new trace, discard what we have. */
- if (errcode == 0 && !VEC_empty (btrace_block_s, btrace))
+ if (errcode == 0 && !btrace_data_empty (&btrace))
btrace_clear (tp);
}
error (_("Failed to read branch trace."));
/* Compute the trace, provided we have any. */
- if (!VEC_empty (btrace_block_s, btrace))
+ if (!btrace_data_empty (&btrace))
{
btrace_clear_history (btinfo);
- btrace_compute_ftrace (btinfo, btrace);
+ btrace_compute_ftrace (tp, &btrace);
}
do_cleanups (cleanup);
btinfo->begin = NULL;
btinfo->end = NULL;
+ btinfo->ngaps = 0;
btrace_clear_history (btinfo);
}
DEBUG ("free objfile");
- ALL_THREADS (tp)
+ ALL_NON_EXITED_THREADS (tp)
btrace_clear (tp);
}
const struct gdb_xml_element *element,
void *user_data, VEC (gdb_xml_value_s) *attributes)
{
- VEC (btrace_block_s) **btrace;
+ struct btrace_data *btrace;
struct btrace_block *block;
ULONGEST *begin, *end;
btrace = user_data;
- block = VEC_safe_push (btrace_block_s, *btrace, NULL);
+
+ switch (btrace->format)
+ {
+ case BTRACE_FORMAT_BTS:
+ break;
+
+ case BTRACE_FORMAT_NONE:
+ btrace->format = BTRACE_FORMAT_BTS;
+ btrace->variant.bts.blocks = NULL;
+ break;
+
+ default:
+ gdb_xml_error (parser, _("Btrace format error."));
+ }
begin = xml_find_attribute (attributes, "begin")->value;
end = xml_find_attribute (attributes, "end")->value;
+ block = VEC_safe_push (btrace_block_s, btrace->variant.bts.blocks, NULL);
block->begin = *begin;
block->end = *end;
}
/* See btrace.h. */
-VEC (btrace_block_s) *
-parse_xml_btrace (const char *buffer)
+void
+parse_xml_btrace (struct btrace_data *btrace, const char *buffer)
{
- VEC (btrace_block_s) *btrace = NULL;
struct cleanup *cleanup;
int errcode;
#if defined (HAVE_LIBEXPAT)
- cleanup = make_cleanup (VEC_cleanup (btrace_block_s), &btrace);
+ btrace->format = BTRACE_FORMAT_NONE;
+
+ cleanup = make_cleanup_btrace_data (btrace);
errcode = gdb_xml_parse_quick (_("btrace"), "btrace.dtd", btrace_elements,
- buffer, &btrace);
+ buffer, btrace);
if (errcode != 0)
error (_("Error parsing branch trace."));
error (_("Cannot process branch trace. XML parsing is not supported."));
#endif /* !defined (HAVE_LIBEXPAT) */
+}
+
+#if defined (HAVE_LIBEXPAT)
+
+/* Parse a btrace-conf "bts" xml record. */
+
+static void
+parse_xml_btrace_conf_bts (struct gdb_xml_parser *parser,
+ const struct gdb_xml_element *element,
+ void *user_data, VEC (gdb_xml_value_s) *attributes)
+{
+ struct btrace_config *conf;
+ struct gdb_xml_value *size;
+
+ conf = user_data;
+ conf->format = BTRACE_FORMAT_BTS;
+ conf->bts.size = 0;
+
+ size = xml_find_attribute (attributes, "size");
+ if (size != NULL)
+ conf->bts.size = (unsigned int) * (ULONGEST *) size->value;
+}
+
+static const struct gdb_xml_attribute btrace_conf_bts_attributes[] = {
+ { "size", GDB_XML_AF_OPTIONAL, gdb_xml_parse_attr_ulongest, NULL },
+ { NULL, GDB_XML_AF_NONE, NULL, NULL }
+};
- return btrace;
+static const struct gdb_xml_element btrace_conf_children[] = {
+ { "bts", btrace_conf_bts_attributes, NULL, GDB_XML_EF_OPTIONAL,
+ parse_xml_btrace_conf_bts, NULL },
+ { NULL, NULL, NULL, GDB_XML_EF_NONE, NULL, NULL }
+};
+
+static const struct gdb_xml_attribute btrace_conf_attributes[] = {
+ { "version", GDB_XML_AF_NONE, NULL, NULL },
+ { NULL, GDB_XML_AF_NONE, NULL, NULL }
+};
+
+static const struct gdb_xml_element btrace_conf_elements[] = {
+ { "btrace-conf", btrace_conf_attributes, btrace_conf_children,
+ GDB_XML_EF_NONE, NULL, NULL },
+ { NULL, NULL, NULL, GDB_XML_EF_NONE, NULL, NULL }
+};
+
+#endif /* defined (HAVE_LIBEXPAT) */
+
+/* See btrace.h. */
+
+void
+parse_xml_btrace_conf (struct btrace_config *conf, const char *xml)
+{
+ int errcode;
+
+#if defined (HAVE_LIBEXPAT)
+
+ errcode = gdb_xml_parse_quick (_("btrace-conf"), "btrace-conf.dtd",
+ btrace_conf_elements, xml, conf);
+ if (errcode != 0)
+ error (_("Error parsing branch trace configuration."));
+
+#else /* !defined (HAVE_LIBEXPAT) */
+
+ error (_("XML parsing is not supported."));
+
+#endif /* !defined (HAVE_LIBEXPAT) */
}
/* See btrace.h. */
index = it->index;
bfun = it->function;
+ /* Check if the iterator points to a gap in the trace. */
+ if (bfun->errcode != 0)
+ return NULL;
+
/* The index is within the bounds of this function's instruction vector. */
end = VEC_length (btrace_insn_s, bfun->insn);
gdb_assert (0 < end);
const struct btrace_function *bfun;
bfun = it->function;
+
+ /* Return zero if the iterator points to a gap in the trace. */
+ if (bfun->errcode != 0)
+ return 0;
+
return bfun->insn_offset + it->index;
}
if (bfun == NULL)
error (_("No trace."));
- /* The last instruction in the last function is the current instruction.
- We point to it - it is one past the end of the execution trace. */
length = VEC_length (btrace_insn_s, bfun->insn);
+ /* The last function may either be a gap or it contains the current
+ instruction, which is one past the end of the execution trace; ignore
+ it. */
+ if (length > 0)
+ length -= 1;
+
it->function = bfun;
- it->index = length - 1;
+ it->index = length;
}
/* See btrace.h. */
end = VEC_length (btrace_insn_s, bfun->insn);
+ /* An empty function segment represents a gap in the trace. We count
+ it as one instruction. */
+ if (end == 0)
+ {
+ const struct btrace_function *next;
+
+ next = bfun->flow.next;
+ if (next == NULL)
+ break;
+
+ stride -= 1;
+ steps += 1;
+
+ bfun = next;
+ index = 0;
+
+ continue;
+ }
+
gdb_assert (0 < end);
gdb_assert (index < end);
bfun = prev;
index = VEC_length (btrace_insn_s, bfun->insn);
- /* There is at least one instruction in this function segment. */
- gdb_assert (index > 0);
+ /* An empty function segment represents a gap in the trace. We count
+ it as one instruction. */
+ if (index == 0)
+ {
+ stride -= 1;
+ steps += 1;
+
+ continue;
+ }
}
/* Advance the iterator as far as possible within this segment. */
adv = min (index, stride);
+
stride -= adv;
index -= adv;
steps += adv;
lnum = btrace_insn_number (lhs);
rnum = btrace_insn_number (rhs);
+ /* A gap has an instruction number of zero. Things are getting more
+ complicated if gaps are involved.
+
+ We take the instruction number offset from the iterator's function.
+ This is the number of the first instruction after the gap.
+
+ This is OK as long as both lhs and rhs point to gaps. If only one of
+ them does, we need to adjust the number based on the other's regular
+ instruction number. Otherwise, a gap might compare equal to an
+ instruction. */
+
+ if (lnum == 0 && rnum == 0)
+ {
+ lnum = lhs->function->insn_offset;
+ rnum = rhs->function->insn_offset;
+ }
+ else if (lnum == 0)
+ {
+ lnum = lhs->function->insn_offset;
+
+ if (lnum == rnum)
+ lnum -= 1;
+ }
+ else if (rnum == 0)
+ {
+ rnum = rhs->function->insn_offset;
+
+ if (rnum == lnum)
+ rnum -= 1;
+ }
+
return (int) (lnum - rnum);
}
unsigned int number)
{
const struct btrace_function *bfun;
- unsigned int end;
+ unsigned int end, length;
for (bfun = btinfo->end; bfun != NULL; bfun = bfun->flow.prev)
- if (bfun->insn_offset <= number)
- break;
+ {
+ /* Skip gaps. */
+ if (bfun->errcode != 0)
+ continue;
+
+ if (bfun->insn_offset <= number)
+ break;
+ }
if (bfun == NULL)
return 0;
- end = bfun->insn_offset + VEC_length (btrace_insn_s, bfun->insn);
+ length = VEC_length (btrace_insn_s, bfun->insn);
+ gdb_assert (length > 0);
+
+ end = bfun->insn_offset + length;
if (end <= number)
return 0;
return btrace_insn_cmp (&begin, &end) == 0;
}
+
+/* Forward the cleanup request. */
+
+static void
+do_btrace_data_cleanup (void *arg)
+{
+ btrace_data_fini (arg);
+}
+
+/* See btrace.h. */
+
+struct cleanup *
+make_cleanup_btrace_data (struct btrace_data *data)
+{
+ return make_cleanup (do_btrace_data_cleanup, data);
+}