FreeChainXenon/binutils-gdb
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

Change breakpoints to use value_ref_ptr

Browse source 
Now that value_ref_ptr exists, it is possible to simplify breakpoint
and bpstat memory management by using a value_ref_ptr rather than
manually handling the reference counts.

gdb/ChangeLog
2018-04-06  Tom Tromey  <tom@tromey.com>

	* value.c (release_value): Update.
	* breakpoint.h (struct watchpoint) <val>: Now a value_ref_ptr.
	(struct bpstats) <val>: Now a value_ref_ptr.
	* breakpoint.c (update_watchpoint, breakpoint_init_inferior)
	(~bpstats, bpstats, bpstat_clear_actions, watchpoint_check)
	(~watchpoint, print_it_watchpoint, watch_command_1)
	(invalidate_bp_value_on_memory_change): Update.
This commit is contained in:
Tom Tromey 2018-04-03 17:58:58 -06:00
parent 22bc8444e6
commit 850645cfe8
4 changed files with 46 additions and 52 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

10
gdb/ChangeLog
View file

@ -1,3 +1,13 @@
2018-04-06 Tom Tromey <tom@tromey.com>
* value.c (release_value): Update.
* breakpoint.h (struct watchpoint) <val>: Now a value_ref_ptr.
(struct bpstats) <val>: Now a value_ref_ptr.
* breakpoint.c (update_watchpoint, breakpoint_init_inferior)
(~bpstats, bpstats, bpstat_clear_actions, watchpoint_check)
(~watchpoint, print_it_watchpoint, watch_command_1)
(invalidate_bp_value_on_memory_change): Update.
2018-04-06 Tom Tromey <tom@tromey.com>
* varobj.c (varobj_clear_saved_item)

80
gdb/breakpoint.c
View file

@ -1740,7 +1740,6 @@ update_watchpoint (struct watchpoint *b, int reparse)
no longer relevant. We don't want to report a watchpoint hit
to the user when the old value and the new value may actually
be completely different objects. */
value_decref (b->val);
b->val = NULL;
b->val_valid = 0;
@ -1792,12 +1791,8 @@ update_watchpoint (struct watchpoint *b, int reparse)
if (!b->val_valid && !is_masked_watchpoint (b))
{
if (b->val_bitsize != 0)
{
v = extract_bitfield_from_watchpoint_value (b, v);
if (v != NULL)
release_value (v).release ();
}
b->val = v;
v = extract_bitfield_from_watchpoint_value (b, v);
b->val = release_value (v);
b->val_valid = 1;
}
@ -3951,9 +3946,7 @@ breakpoint_init_inferior (enum inf_context context)
{
/* Reset val field to force reread of starting value in
insert_breakpoints. */
if (w->val)
value_decref (w->val);
w->val = NULL;
w->val.reset (nullptr);
w->val_valid = 0;
}
}
@ -4199,8 +4192,6 @@ is_catchpoint (struct breakpoint *ep)
bpstats::~bpstats ()
{
if (old_val != NULL)
value_decref (old_val);
if (bp_location_at != NULL)
decref_bp_location (&bp_location_at);
}
@ -4231,13 +4222,12 @@ bpstats::bpstats (const bpstats &other)
bp_location_at (other.bp_location_at),
breakpoint_at (other.breakpoint_at),
commands (other.commands),
old_val (other.old_val),
print (other.print),
stop (other.stop),
print_it (other.print_it)
{
if (old_val != NULL)
old_val = release_value (value_copy (old_val)).release ();
if (other.old_val != NULL)
old_val = release_value (value_copy (other.old_val.get ()));
incref_bp_location (bp_location_at);
}
@ -4358,12 +4348,7 @@ bpstat_clear_actions (void)
for (bs = tp->control.stop_bpstat; bs != NULL; bs = bs->next)
{
bs->commands = NULL;
if (bs->old_val != NULL)
{
value_decref (bs->old_val);
bs->old_val = NULL;
}
bs->old_val.reset (nullptr);
}
}
@ -4725,7 +4710,6 @@ bpstats::bpstats (struct bp_location *bl, bpstat **bs_link_pointer)
bp_location_at (bl),
breakpoint_at (bl->owner),
commands (NULL),
old_val (NULL),
print (0),
stop (0),
print_it (print_it_normal)
@ -4740,7 +4724,6 @@ bpstats::bpstats ()
bp_location_at (NULL),
breakpoint_at (NULL),
commands (NULL),
old_val (NULL),
print (0),
stop (0),
print_it (print_it_normal)
@ -4935,16 +4918,14 @@ watchpoint_check (bpstat bs)
the address of the array instead of its contents. This is
not what we want. */
if ((b->val != NULL) != (new_val != NULL)
|| (b->val != NULL && !value_equal_contents (b->val, new_val)))
|| (b->val != NULL && !value_equal_contents (b->val.get (),
new_val)))
{
if (new_val != NULL)
{
release_value (new_val).release ();
value_free_to_mark (mark);
}
bs->old_val = b->val;
b->val = new_val;
b->val = release_value (new_val);
b->val_valid = 1;
if (new_val != NULL)
value_free_to_mark (mark);
return WP_VALUE_CHANGED;
}
else
@ -10099,7 +10080,6 @@ watchpoint::~watchpoint ()
{
xfree (this->exp_string);
xfree (this->exp_string_reparse);
value_decref (this->val);
}
/* Implement the "re_set" breakpoint_ops method for watchpoints. */
@ -10241,10 +10221,10 @@ print_it_watchpoint (bpstat bs)
mention (b);
tuple_emitter.emplace (uiout, "value");
uiout->text ("\nOld value = ");
watchpoint_value_print (bs->old_val, &stb);
watchpoint_value_print (bs->old_val.get (), &stb);
uiout->field_stream ("old", stb);
uiout->text ("\nNew value = ");
watchpoint_value_print (w->val, &stb);
watchpoint_value_print (w->val.get (), &stb);
uiout->field_stream ("new", stb);
uiout->text ("\n");
/* More than one watchpoint may have been triggered. */
@ -10258,7 +10238,7 @@ print_it_watchpoint (bpstat bs)
mention (b);
tuple_emitter.emplace (uiout, "value");
uiout->text ("\nValue = ");
watchpoint_value_print (w->val, &stb);
watchpoint_value_print (w->val.get (), &stb);
uiout->field_stream ("value", stb);
uiout->text ("\n");
result = PRINT_UNKNOWN;
@ -10274,7 +10254,7 @@ print_it_watchpoint (bpstat bs)
mention (b);
tuple_emitter.emplace (uiout, "value");
uiout->text ("\nOld value = ");
watchpoint_value_print (bs->old_val, &stb);
watchpoint_value_print (bs->old_val.get (), &stb);
uiout->field_stream ("old", stb);
uiout->text ("\nNew value = ");
}
@ -10288,7 +10268,7 @@ print_it_watchpoint (bpstat bs)
tuple_emitter.emplace (uiout, "value");
uiout->text ("\nValue = ");
}
watchpoint_value_print (w->val, &stb);
watchpoint_value_print (w->val.get (), &stb);
uiout->field_stream ("new", stb);
uiout->text ("\n");
result = PRINT_UNKNOWN;
@ -10583,7 +10563,7 @@ watch_command_1 (const char *arg, int accessflag, int from_tty,
{
struct breakpoint *scope_breakpoint = NULL;
const struct block *exp_valid_block = NULL, *cond_exp_valid_block = NULL;
struct value *val, *mark, *result;
struct value *mark, *result;
int saved_bitpos = 0, saved_bitsize = 0;
const char *exp_start = NULL;
const char *exp_end = NULL;
@ -10709,25 +10689,28 @@ watch_command_1 (const char *arg, int accessflag, int from_tty,
exp_valid_block = innermost_block.block ();
mark = value_mark ();
fetch_subexp_value (exp.get (), &pc, &val, &result, NULL, just_location);
struct value *val_as_value = nullptr;
fetch_subexp_value (exp.get (), &pc, &val_as_value, &result, NULL,
just_location);
if (val != NULL && just_location)
if (val_as_value != NULL && just_location)
{
saved_bitpos = value_bitpos (val);
saved_bitsize = value_bitsize (val);
saved_bitpos = value_bitpos (val_as_value);
saved_bitsize = value_bitsize (val_as_value);
}
value_ref_ptr val;
if (just_location)
{
int ret;
exp_valid_block = NULL;
val = release_value (value_addr (result)).release ();
val = release_value (value_addr (result));
value_free_to_mark (mark);
if (use_mask)
{
ret = target_masked_watch_num_registers (value_as_address (val),
ret = target_masked_watch_num_registers (value_as_address (val.get ()),
mask);
if (ret == -1)
error (_("This target does not support masked watchpoints."));
@ -10735,8 +10718,8 @@ watch_command_1 (const char *arg, int accessflag, int from_tty,
error (_("Invalid mask or memory region."));
}
}
else if (val != NULL)
release_value (val).release ();
else if (val_as_value != NULL)
val = release_value (val_as_value);
tok = skip_spaces (arg);
end_tok = skip_to_space (tok);
@ -10830,8 +10813,8 @@ watch_command_1 (const char *arg, int accessflag, int from_tty,
w->cond_exp_valid_block = cond_exp_valid_block;
if (just_location)
{
struct type *t = value_type (val);
CORE_ADDR addr = value_as_address (val);
struct type *t = value_type (val.get ());
CORE_ADDR addr = value_as_address (val.get ());
w->exp_string_reparse
= current_language->la_watch_location_expression (t, addr).release ();
@ -14533,7 +14516,7 @@ invalidate_bp_value_on_memory_change (struct inferior *inferior,
{
struct watchpoint *wp = (struct watchpoint *) bp;
if (wp->val_valid && wp->val)
if (wp->val_valid && wp->val != nullptr)
{
struct bp_location *loc;
@ -14542,7 +14525,6 @@ invalidate_bp_value_on_memory_change (struct inferior *inferior,
&& loc->address + loc->length > addr
&& addr + len > loc->address)
{
value_decref (wp->val);
wp->val = NULL;
wp->val_valid = 0;
}

5
gdb/breakpoint.h
View file

@ -31,7 +31,6 @@
#include "common/array-view.h"
#include "cli/cli-script.h"
struct value;
struct block;
struct gdbpy_breakpoint_object;
struct gdbscm_breakpoint_object;
@ -813,7 +812,7 @@ struct watchpoint : public breakpoint
/* Value of the watchpoint the last time we checked it, or NULL when
we do not know the value yet or the value was not readable. VAL
is never lazy. */
struct value *val;
value_ref_ptr val;
/* Nonzero if VAL is valid. If VAL_VALID is set but VAL is NULL,
then an error occurred reading the value. */
int val_valid;
@ -1125,7 +1124,7 @@ struct bpstats
counted_command_line commands;
/* Old value associated with a watchpoint. */
struct value *old_val;
value_ref_ptr old_val;
/* Nonzero if this breakpoint tells us to print the frame. */
char print;

3
gdb/value.c
View file

@ -1696,6 +1696,9 @@ release_value (struct value *val)
struct value *v;
bool released = false;
if (val == nullptr)
return value_ref_ptr ();
if (all_values == val)
{
all_values = val->next;