[RFA,5/9] Explicit locations v2 - Add probe locations
Commit Message
This is also an update of this patch based on feedback from previous
patch reviews.
Keith
Changes since last revision:
- use make_cleanup_delete_event_location
- remove SAVE_SPEC
- new_probe_location
ChangeLog
2014-05-29 Keith Seitz <keiths@redhat.com>
* 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): Handel probe locations.
* location.h (enum event_location_type): Add PROBE_LOCATION.
(EVENT_LOCATION_PROBE): Define accessor macro.
* probe.c (parse_probes): Assert that LOCATION is a probe location.
Convert linespec into probe location.
Comments
Hi. Comments inline, mostly nits.
Keith Seitz writes:
> This is also an update of this patch based on feedback from previous
> patch reviews.
>
> Keith
>
> Changes since last revision:
> - use make_cleanup_delete_event_location
> - remove SAVE_SPEC
> - new_probe_location
>
> ChangeLog
> 2014-05-29 Keith Seitz <keiths@redhat.com>
>
> * 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): Handel probe locations.
"Handle ...", or just "Likewise."
> * location.h (enum event_location_type): Add PROBE_LOCATION.
> (EVENT_LOCATION_PROBE): Define accessor macro.
> * probe.c (parse_probes): Assert that LOCATION is a probe location.
> Convert linespec into probe location.
>
>
>
> diff --git a/gdb/break-catch-throw.c b/gdb/break-catch-throw.c
> index e2c8365..207e7af 100644
> --- a/gdb/break-catch-throw.c
> +++ b/gdb/break-catch-throw.c
> @@ -214,8 +214,8 @@ re_set_exception_catchpoint (struct breakpoint *self)
> {
> struct event_location location;
>
> - initialize_event_location (&location, LINESPEC_LOCATION);
> - EVENT_LOCATION_LINESPEC (&location)
> + initialize_event_location (&location, PROBE_LOCATION);
> + EVENT_LOCATION_PROBE (&location)
> = ASTRDUP (exception_functions[kind].probe);
> sals = parse_probes (&location, NULL);
> }
> diff --git a/gdb/breakpoint.c b/gdb/breakpoint.c
> index ef60f44..345b104 100644
> --- a/gdb/breakpoint.c
> +++ b/gdb/breakpoint.c
> @@ -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;
> }
>
> @@ -10068,7 +10068,6 @@ 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;
>
> @@ -10076,7 +10075,8 @@ 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;
> @@ -15432,11 +15432,11 @@ 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;
> diff --git a/gdb/linespec.c b/gdb/linespec.c
> index 8ea0c7b..deda86e 100644
> --- a/gdb/linespec.c
> +++ b/gdb/linespec.c
> @@ -2433,6 +2433,11 @@ event_location_to_sals (linespec_parser *parser,
> EVENT_LOCATION_ADDRESS (location));
> break;
>
> + case PROBE_LOCATION:
> + /* Probes are handled by their own decoders. */
> + gdb_assert_not_reached ("attempt to decode probe location");
extra space of indentation
> + break;
> +
> default:
> gdb_assert_not_reached ("unhandled event location type");
> }
> diff --git a/gdb/location.c b/gdb/location.c
> index 3c430db..eafa27d 100644
> --- a/gdb/location.c
> +++ b/gdb/location.c
> @@ -67,6 +67,21 @@ new_address_location (CORE_ADDR addr)
> return location;
> }
>
> +/* Create a new probe location. The return result is malloc'd
> + and should be freed with delete_event_location. */
> +
> +struct event_location *
> +new_probe_location (const char *probe)
> +{
> + struct event_location *location;
> +
> + location = XNEW (struct event_location);
> + initialize_event_location (location, PROBE_LOCATION);
> + if (probe != NULL)
> + EVENT_LOCATION_PROBE (location) = xstrdup (probe);
> + return location;
> +}
> +
> /* Return a copy of the given SRC location. */
>
> struct event_location *
> @@ -89,6 +104,10 @@ copy_event_location (const struct event_location *src)
> EVENT_LOCATION_ADDRESS (dst) = EVENT_LOCATION_ADDRESS (src);
> break;
>
> + case PROBE_LOCATION:
> + EVENT_LOCATION_PROBE (dst) = xstrdup (EVENT_LOCATION_PROBE (src));
> + break;
> +
> default:
> gdb_assert_not_reached ("unknown event location type");
> }
> @@ -133,6 +152,10 @@ delete_event_location (struct event_location *location)
> /* Nothing to do. */
> break;
>
> + case PROBE_LOCATION:
> + xfree (EVENT_LOCATION_PROBE (location));
> + break;
> +
> default:
> gdb_assert_not_reached ("unknown event location type");
> }
> @@ -166,6 +189,10 @@ event_location_to_string_const (const struct event_location *location)
> core_addr_to_string (EVENT_LOCATION_ADDRESS (location)));
> break;
>
> + case PROBE_LOCATION:
> + result = xstrdup (EVENT_LOCATION_PROBE (location));
> + break;
> +
> default:
> gdb_assert_not_reached ("unknown event location type");
> }
> @@ -212,10 +239,23 @@ 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);
> + if (*stringp != NULL)
This test is unnecessary (right?).
btw, when will this function be passed *stringp == NULL?
Can this function have an "early exit" if *stringp == NULL?
[assuming that makes sense]
> + *stringp += strlen (*stringp);
> + }
> + else
> + {
> + /* Everything else is a linespec. */
> + location = new_linespec_location (*stringp);
> + if (*stringp != NULL)
> + *stringp += strlen (*stringp);
> + }
> }
>
> return location;
> @@ -234,6 +274,9 @@ event_location_empty_p (const struct event_location *location)
> case ADDRESS_LOCATION:
> return 0;
>
> + case PROBE_LOCATION:
> + return EVENT_LOCATION_PROBE (location) == NULL;
> +
> default:
> gdb_assert_not_reached ("unknown event location type");
> }
> diff --git a/gdb/location.h b/gdb/location.h
> index 1daefb6..e6f14d9 100644
> --- a/gdb/location.h
> +++ b/gdb/location.h
> @@ -30,7 +30,10 @@ enum event_location_type
> LINESPEC_LOCATION,
>
> /* An address in the inferior. */
> - ADDRESS_LOCATION
> + ADDRESS_LOCATION,
> +
> + /* A probe location. */
> + PROBE_LOCATION
> };
>
> /* An event location used to set a stop event in the inferior.
> @@ -50,6 +53,7 @@ struct event_location
> probes. */
> char *addr_string;
> #define EVENT_LOCATION_LINESPEC(S) ((S)->u.addr_string)
> +#define EVENT_LOCATION_PROBE(S) ((S)->u.addr_string)
>
> /* An address in the inferior. */
> CORE_ADDR address;
> @@ -98,6 +102,12 @@ extern struct event_location *
> extern struct event_location *
> new_address_location (CORE_ADDR addr);
>
> +/* 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 a copy of the given SRC location. */
>
> extern struct event_location *
> diff --git a/gdb/probe.c b/gdb/probe.c
> index c7597d9..2ff5d86 100644
> --- a/gdb/probe.c
> +++ b/gdb/probe.c
> @@ -58,7 +58,8 @@ parse_probes (struct event_location *location,
> result.sals = NULL;
> result.nelts = 0;
>
> - arg_start = EVENT_LOCATION_LINESPEC (location);
> + gdb_assert (EVENT_LOCATION_TYPE (location) == PROBE_LOCATION);
> + arg_start = EVENT_LOCATION_PROBE (location);
>
> cs = arg_start;
> probe_ops = probe_linespec_to_ops (&cs);
> @@ -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.
> }
>
> - 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]
>
> return result;
On Sat, Aug 2, 2014 at 4:38 PM, Doug Evans <dje@google.com> wrote:
> [...]
> > diff --git a/gdb/probe.c b/gdb/probe.c
> > index c7597d9..2ff5d86 100644
> > --- a/gdb/probe.c
> > +++ b/gdb/probe.c
> > @@ -58,7 +58,8 @@ parse_probes (struct event_location *location,
> > result.sals = NULL;
> > result.nelts = 0;
> >
> > - arg_start = EVENT_LOCATION_LINESPEC (location);
> > + gdb_assert (EVENT_LOCATION_TYPE (location) == PROBE_LOCATION);
> > + arg_start = EVENT_LOCATION_PROBE (location);
> >
> > cs = arg_start;
> > probe_ops = probe_linespec_to_ops (&cs);
> > @@ -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.
OTOH, is that, or any other variation, excessive?
It's preferable to not have users of object foo know how to physically
construct a foo.
/just a thought for discussion's sake - I wouldn't change the patch if
this is but one of many similar instances, unless it makes sense to
change all of them.
@@ -214,8 +214,8 @@ re_set_exception_catchpoint (struct breakpoint *self)
{
struct event_location location;
- initialize_event_location (&location, LINESPEC_LOCATION);
- EVENT_LOCATION_LINESPEC (&location)
+ initialize_event_location (&location, PROBE_LOCATION);
+ EVENT_LOCATION_PROBE (&location)
= ASTRDUP (exception_functions[kind].probe);
sals = parse_probes (&location, NULL);
}
@@ -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;
}
@@ -10068,7 +10068,6 @@ 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;
@@ -10076,7 +10075,8 @@ 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;
@@ -15432,11 +15432,11 @@ 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,
EVENT_LOCATION_ADDRESS (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");
}
@@ -67,6 +67,21 @@ new_address_location (CORE_ADDR addr)
return location;
}
+/* Create a new probe location. The return result is malloc'd
+ and should be freed with delete_event_location. */
+
+struct event_location *
+new_probe_location (const char *probe)
+{
+ struct event_location *location;
+
+ location = XNEW (struct event_location);
+ initialize_event_location (location, PROBE_LOCATION);
+ if (probe != NULL)
+ EVENT_LOCATION_PROBE (location) = xstrdup (probe);
+ return location;
+}
+
/* Return a copy of the given SRC location. */
struct event_location *
@@ -89,6 +104,10 @@ copy_event_location (const struct event_location *src)
EVENT_LOCATION_ADDRESS (dst) = EVENT_LOCATION_ADDRESS (src);
break;
+ case PROBE_LOCATION:
+ EVENT_LOCATION_PROBE (dst) = xstrdup (EVENT_LOCATION_PROBE (src));
+ break;
+
default:
gdb_assert_not_reached ("unknown event location type");
}
@@ -133,6 +152,10 @@ delete_event_location (struct event_location *location)
/* Nothing to do. */
break;
+ case PROBE_LOCATION:
+ xfree (EVENT_LOCATION_PROBE (location));
+ break;
+
default:
gdb_assert_not_reached ("unknown event location type");
}
@@ -166,6 +189,10 @@ event_location_to_string_const (const struct event_location *location)
core_addr_to_string (EVENT_LOCATION_ADDRESS (location)));
break;
+ case PROBE_LOCATION:
+ result = xstrdup (EVENT_LOCATION_PROBE (location));
+ break;
+
default:
gdb_assert_not_reached ("unknown event location type");
}
@@ -212,10 +239,23 @@ 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);
+ if (*stringp != NULL)
+ *stringp += strlen (*stringp);
+ }
+ else
+ {
+ /* Everything else is a linespec. */
+ location = new_linespec_location (*stringp);
+ if (*stringp != NULL)
+ *stringp += strlen (*stringp);
+ }
}
return location;
@@ -234,6 +274,9 @@ event_location_empty_p (const struct event_location *location)
case ADDRESS_LOCATION:
return 0;
+ case PROBE_LOCATION:
+ return EVENT_LOCATION_PROBE (location) == NULL;
+
default:
gdb_assert_not_reached ("unknown event location type");
}
@@ -30,7 +30,10 @@ enum event_location_type
LINESPEC_LOCATION,
/* An address in the inferior. */
- ADDRESS_LOCATION
+ ADDRESS_LOCATION,
+
+ /* A probe location. */
+ PROBE_LOCATION
};
/* An event location used to set a stop event in the inferior.
@@ -50,6 +53,7 @@ struct event_location
probes. */
char *addr_string;
#define EVENT_LOCATION_LINESPEC(S) ((S)->u.addr_string)
+#define EVENT_LOCATION_PROBE(S) ((S)->u.addr_string)
/* An address in the inferior. */
CORE_ADDR address;
@@ -98,6 +102,12 @@ extern struct event_location *
extern struct event_location *
new_address_location (CORE_ADDR addr);
+/* 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 a copy of the given SRC location. */
extern struct event_location *
@@ -58,7 +58,8 @@ parse_probes (struct event_location *location,
result.sals = NULL;
result.nelts = 0;
- arg_start = EVENT_LOCATION_LINESPEC (location);
+ gdb_assert (EVENT_LOCATION_TYPE (location) == PROBE_LOCATION);
+ arg_start = EVENT_LOCATION_PROBE (location);
cs = arg_start;
probe_ops = probe_linespec_to_ops (&cs);
@@ -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);
}
- EVENT_LOCATION_LINESPEC (location) = arg_end;
+ EVENT_LOCATION_PROBE (location) = arg_end;
do_cleanups (cleanup);
return result;