[RFA,5/9] Explicit locations v2 - Add probe locations
Commit Message
On 08/02/2014 04:38 PM, Doug Evans wrote:
> > (event_location_empty_p): Handel probe locations.
>
> "Handle ...", or just "Likewise."
Fixed.
> > + case PROBE_LOCATION:
> > + /* Probes are handled by their own decoders. */
> > + gdb_assert_not_reached ("attempt to decode probe location");
>
> extra space of indentation
Fixed.
> > + if (cs != NULL && probe_linespec_to_ops (&cs) != NULL)
> > + {
> > + location = new_probe_location (*stringp);
> > + if (*stringp != NULL)
>
> This test is unnecessary (right?).
Yes, that's correct. I've removed it.
> btw, when will this function be passed *stringp == NULL?
> Can this function have an "early exit" if *stringp == NULL?
> [assuming that makes sense]
NULL is a valid linespec, e.g, a user does:
(gdb) start
(gdb) break
Breakpoint 1, ...
As to an early exit, ... I didn't implement it. If you would like me to,
just say the word!
> > @@ -173,12 +174,12 @@ parse_probes (struct event_location *location,
> > {
> > canonical->special_display = 1;
> > canonical->pre_expanded = 1;
> > - canonical->location = new_linespec_location (NULL);
> > - EVENT_LOCATION_LINESPEC (canonical->location)
> > + canonical->location = new_probe_location (NULL);
> > + EVENT_LOCATION_PROBE (canonical->location)
> > = savestring (arg_start, arg_end - arg_start);
>
> I see why you pass NULL to new_probe_location and then set EVENT_LOCATION_PROBE
> afterwards (otherwise two copies of the string would be malloc'd, and you'd
> need to deal with freeing one of them). One could add a version of
> new_probe_location that took a char* and a length, but that seems excessive.
> Another place where c++ would allow cleaner code.
As mentioned in patch #4, I've fixed in the prescribed manner (free the
savestring after calling the ctor).
>
> > }
> >
> > - EVENT_LOCATION_LINESPEC (location) = arg_end;
> > + EVENT_LOCATION_PROBE (location) = arg_end;
> > do_cleanups (cleanup);
>
> The function starts out with:
>
> arg_start = EVENT_LOCATION_PROBE (location);
>
> and at the end we do this:
>
> EVENT_LOCATION_PROBE (location) = arg_end;
>
> IWBN to document why we do this, it's not obvious to me why that is.
> [doesn't have to be part of this patch set though]
This now uses the more explicit API functions to do this,
event_location_advance_ptr and added a comment. [Of course, this is part
of the "skip past any processed input" paradigm that we have to deal
with for linespecs/probes.]
>
> >
> > return result;
>
Updated patch attached.
Keith
Changes since last revision:
- Fix "Handel" in ChangeLog
- Remove leading whitespace
- Remove unnecessary NULL check in string_to_event_location
- Pass savestring() to new_probe_location instead of
NULL and accessing struct directly
- Use functions instead of EVENT_LOCAITON_* macros.
- Add comment and use event_location_advance_ptr to "skip"
past processed input in parse_probes
gdb/ChangeLog:
* break-catch-throw.c (re_set_exception_catchpoint): Convert
linespec for stap probe to probe location.
* breakpoint.c (create_longjmp_master_breakpoint): Likewise.
(create_exception_master_breakpoint): Likewise.
(break_command_1): Remove local variable `arg_cp'.
Check location type to set appropriate breakpoint ops methods.
(trace_command): Likewise.
* linespec.c (event_location_to_sals): Handle probe locations.
* location.c (copy_event_location): Likewise.
(delete_event_location): Likewise.
(event_location_to_string): Likewise.
(string_to_event_location): Likewise.
(event_location_empty_p): Likewise.
* location.h (enum event_location_type): Add PROBE_LOCATION.
* probe.c (parse_probes): Assert that LOCATION is a probe location.
Convert linespec into probe location.
---
gdb/break-catch-throw.c | 2 +
gdb/breakpoint.c | 12 ++++-----
gdb/linespec.c | 5 ++++
gdb/location.c | 64 ++++++++++++++++++++++++++++++++++++++++++++---
gdb/location.h | 17 ++++++++++++
gdb/probe.c | 7 +++--
6 files changed, 92 insertions(+), 15 deletions(-)
@@ -212,7 +212,7 @@ re_set_exception_catchpoint (struct breakpoint *self)
/* We first try to use the probe interface. */
location
- = new_linespec_location (ASTRDUP (exception_functions[kind].probe));
+ = new_probe_location (ASTRDUP (exception_functions[kind].probe));
cleanup = make_cleanup_delete_event_location (location);
copy_location = copy_event_location_tmp (location);
make_cleanup (xfree, copy_location);
@@ -3387,7 +3387,7 @@ create_longjmp_master_breakpoint (void)
bp_longjmp_master,
&internal_breakpoint_ops);
b->location
- = new_linespec_location ("-probe-stap libc:longjmp");
+ = new_probe_location ("-probe-stap libc:longjmp");
b->enable_state = bp_disabled;
}
@@ -3551,7 +3551,7 @@ create_exception_master_breakpoint (void)
bp_exception_master,
&internal_breakpoint_ops);
b->location
- = new_linespec_location ("-probe-stap libgcc:unwind");
+ = new_probe_location ("-probe-stap libgcc:unwind");
b->enable_state = bp_disabled;
}
@@ -10082,7 +10082,6 @@ break_command_1 (char *arg, int flag, int from_tty)
? bp_hardware_breakpoint
: bp_breakpoint);
struct breakpoint_ops *ops;
- const char *arg_cp = arg;
struct event_location *location;
struct cleanup *cleanup;
@@ -10090,7 +10089,8 @@ break_command_1 (char *arg, int flag, int from_tty)
cleanup = make_cleanup_delete_event_location (location);
/* Matching breakpoints on probes. */
- if (arg_cp != NULL && probe_linespec_to_ops (&arg_cp) != NULL)
+ if (location != NULL
+ && event_location_type (location) == PROBE_LOCATION)
ops = &bkpt_probe_breakpoint_ops;
else
ops = &bkpt_breakpoint_ops;
@@ -15453,11 +15453,11 @@ trace_command (char *arg, int from_tty)
struct breakpoint_ops *ops;
struct event_location *location;
struct cleanup *back_to;
- const char *arg_cp = arg;
location = string_to_event_location (&arg, current_language);
back_to = make_cleanup_delete_event_location (location);
- if (arg_cp != NULL && probe_linespec_to_ops (&arg_cp) != NULL)
+ if (location != NULL
+ && event_location_type (location) == PROBE_LOCATION)
ops = &tracepoint_probe_breakpoint_ops;
else
ops = &tracepoint_breakpoint_ops;
@@ -2433,6 +2433,11 @@ event_location_to_sals (linespec_parser *parser,
get_address_location (location));
break;
+ case PROBE_LOCATION:
+ /* Probes are handled by their own decoders. */
+ gdb_assert_not_reached ("attempt to decode probe location");
+ break;
+
default:
gdb_assert_not_reached ("unhandled event location type");
}
@@ -45,6 +45,7 @@ struct event_location
probes. */
char *addr_string;
#define EL_LINESPEC(PTR) ((PTR)->u.addr_string)
+#define EL_PROBE(PTR) ((PTR)->u.addr_string)
/* An address in the inferior. */
CORE_ADDR address;
@@ -113,6 +114,29 @@ get_address_location (struct event_location *location)
/* See description in location.h. */
struct event_location *
+new_probe_location (const char *probe)
+{
+ struct event_location *location;
+
+ location = XCNEW (struct event_location);
+ EL_TYPE (location) = PROBE_LOCATION;
+ if (probe != NULL)
+ EL_PROBE (location) = xstrdup (probe);
+ return location;
+}
+
+/* See description in location.h. */
+
+char *
+get_probe_location (struct event_location *location)
+{
+ gdb_assert (EL_TYPE (location) == PROBE_LOCATION);
+ return EL_PROBE (location);
+}
+
+/* See description in location.h. */
+
+struct event_location *
copy_event_location (const struct event_location *src)
{
struct event_location *dst;
@@ -133,6 +157,11 @@ copy_event_location (const struct event_location *src)
EL_ADDRESS (dst) = EL_ADDRESS (src);
break;
+ case PROBE_LOCATION:
+ if (EL_PROBE (src) != NULL)
+ EL_PROBE (dst) = xstrdup (EL_PROBE (src));
+ break;
+
default:
gdb_assert_not_reached ("unknown event location type");
}
@@ -177,6 +206,10 @@ delete_event_location (struct event_location *location)
/* Nothing to do. */
break;
+ case PROBE_LOCATION:
+ xfree (EL_PROBE (location));
+ break;
+
default:
gdb_assert_not_reached ("unknown event location type");
}
@@ -219,6 +252,10 @@ event_location_to_string_const (const struct event_location *location)
core_addr_to_string (EL_ADDRESS (location)));
break;
+ case PROBE_LOCATION:
+ result = xstrdup (EL_PROBE (location));
+ break;
+
default:
gdb_assert_not_reached ("unknown event location type");
}
@@ -259,10 +296,22 @@ string_to_event_location (char **stringp,
}
else
{
- /* Everything else is a linespec. */
- location = new_linespec_location (*stringp);
- if (*stringp != NULL)
- *stringp += strlen (*stringp);
+ const char *cs;
+
+ /* Next, try the input as a probe spec. */
+ cs = *stringp;
+ if (cs != NULL && probe_linespec_to_ops (&cs) != NULL)
+ {
+ location = new_probe_location (*stringp);
+ *stringp += strlen (*stringp);
+ }
+ else
+ {
+ /* Everything else is a linespec. */
+ location = new_linespec_location (*stringp);
+ if (*stringp != NULL)
+ *stringp += strlen (*stringp);
+ }
}
return location;
@@ -282,6 +331,9 @@ event_location_empty_p (const struct event_location *location)
case ADDRESS_LOCATION:
return 0;
+ case PROBE_LOCATION:
+ return EL_PROBE (location) == NULL;
+
default:
gdb_assert_not_reached ("unknown event location type");
}
@@ -294,6 +346,8 @@ void event_location_advance_input_ptr (char **inp,
{
if (EL_TYPE (location) == LINESPEC_LOCATION)
*inp = EL_LINESPEC (location);
+ else if (EL_TYPE (location) == PROBE_LOCATION)
+ *inp = EL_PROBE (location);
}
/* See description in location.h. */
@@ -303,6 +357,8 @@ advance_event_location_ptr (struct event_location *location, size_t num)
{
if (EL_TYPE (location) == LINESPEC_LOCATION)
EL_LINESPEC (location) += num;
+ else if (EL_TYPE (location) == PROBE_LOCATION)
+ EL_PROBE (location) += num;
}
/* See description in location.h. */
@@ -31,7 +31,10 @@ enum event_location_type
LINESPEC_LOCATION,
/* An address in the inferior. */
- ADDRESS_LOCATION
+ ADDRESS_LOCATION,
+
+ /* A probe location. */
+ PROBE_LOCATION
};
/* Return the type of the given event location. */
@@ -79,6 +82,18 @@ extern struct event_location *
extern CORE_ADDR
get_address_location (struct event_location *location);
+/* Create a new probe location. The return result is malloc'd
+ and should be freed with delete_event_location. */
+
+extern struct event_location *
+ new_probe_location (const char *probe);
+
+/* Return the probe location (a string) of the given event_location
+ (which must be of type PROBE_LOCATION). */
+
+extern char *
+ get_probe_location (struct event_location *location);
+
/* Free an event location and any associated data. */
extern void delete_event_location (struct event_location *location);
@@ -58,7 +58,8 @@ parse_probes (struct event_location *location,
result.sals = NULL;
result.nelts = 0;
- arg_start = get_linespec_location (location);
+ gdb_assert (event_location_type (location) == PROBE_LOCATION);
+ arg_start = get_probe_location (location);
cs = arg_start;
probe_ops = probe_linespec_to_ops (&cs);
@@ -175,11 +176,11 @@ parse_probes (struct event_location *location,
canonical->special_display = 1;
canonical->pre_expanded = 1;
- canonical->location = new_linespec_location (canon);
+ canonical->location = new_probe_location (canon);
xfree (canon);
}
- /* Advance the location past all parsed input. */
+ /* Advance the probe location past all parsed input. */
advance_event_location_ptr (location, arg_end - arg_start);
do_cleanups (cleanup);