static void mark_breakpoints_out (void);
+static struct bp_location *
+allocate_bp_location (struct breakpoint *bpt, enum bptype bp_type);
+
+static void
+unlink_locations_from_global_list (struct breakpoint *bpt);
+
+static int
+is_hardware_watchpoint (struct breakpoint *bpt);
+
/* Prototypes for exported functions. */
/* If FALSE, gdb will not use hardware support for watchpoints, even
}
}
-/* Helper routine: free the value chain for a breakpoint (watchpoint). */
+static int
+is_hardware_watchpoint (struct breakpoint *bpt)
+{
+ return (bpt->type == bp_hardware_watchpoint
+ || bpt->type == bp_read_watchpoint
+ || bpt->type == bp_access_watchpoint);
+}
+/* Assuming that B is a hardware breakpoint:
+ - Reparse watchpoint expression, is REPARSE is non-zero
+ - Evaluate expression and store the result in B->val
+ - Update the list of values that must be watched in B->loc.
+
+ If the watchpoint is disabled, do nothing. If this is
+ local watchpoint that is out of scope, delete it. */
static void
-free_valchain (struct bp_location *b)
+update_watchpoint (struct breakpoint *b, int reparse)
{
- struct value *v;
- struct value *n;
+ int within_current_scope;
+ struct value *mark = value_mark ();
+ struct frame_id saved_frame_id;
+ struct bp_location *loc;
+ bpstat bs;
+
+ unlink_locations_from_global_list (b);
+ for (loc = b->loc; loc;)
+ {
+ struct bp_location *loc_next = loc->next;
+ remove_breakpoint (loc, mark_uninserted);
+ xfree (loc);
+ loc = loc_next;
+ }
+ b->loc = NULL;
- /* Free the saved value chain. We will construct a new one
- the next time the watchpoint is inserted. */
- for (v = b->owner->val_chain; v; v = n)
+ if (b->disposition == disp_del_at_next_stop)
+ return;
+
+ /* Save the current frame's ID so we can restore it after
+ evaluating the watchpoint expression on its own frame. */
+ /* FIXME drow/2003-09-09: It would be nice if evaluate_expression
+ took a frame parameter, so that we didn't have to change the
+ selected frame. */
+ saved_frame_id = get_frame_id (get_selected_frame (NULL));
+
+ /* Determine if the watchpoint is within scope. */
+ if (b->exp_valid_block == NULL)
+ within_current_scope = 1;
+ else
{
- n = value_next (v);
- value_free (v);
+ struct frame_info *fi;
+ fi = frame_find_by_id (b->watchpoint_frame);
+ within_current_scope = (fi != NULL);
+ if (within_current_scope)
+ select_frame (fi);
+ }
+
+ if (within_current_scope && reparse)
+ {
+ char *s;
+ if (b->exp)
+ {
+ xfree (b->exp);
+ b->exp = NULL;
+ }
+ s = b->exp_string;
+ b->exp = parse_exp_1 (&s, b->exp_valid_block, 0);
+ /* If the meaning of expression itself changed, the old value is
+ 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_free (b->val);
+ b->val = NULL;
}
- b->owner->val_chain = NULL;
+
+
+ /* If we failed to parse the expression, for example because
+ it refers to a global variable in a not-yet-loaded shared library,
+ don't try to insert watchpoint. We don't automatically delete
+ such watchpoint, though, since failure to parse expression
+ is different from out-of-scope watchpoint. */
+ if (within_current_scope && b->exp)
+ {
+ struct value *v, *next;
+
+ /* Evaluate the expression and make sure it's not lazy, so that
+ after target stops again, we have a non-lazy previous value
+ to compare with. Also, making the value non-lazy will fetch
+ intermediate values as needed, which we use to decide which
+ addresses to watch.
+
+ The value returned by evaluate_expression is stored in b->val.
+ In addition, we look at all values which were created
+ during evaluation, and set watchoints at addresses as needed.
+ Those values are explicitly deleted here. */
+ v = evaluate_expression (b->exp);
+ /* Avoid setting b->val if it's already set. The meaning of
+ b->val is 'the last value' user saw, and we should update
+ it only if we reported that last value to user. As it
+ happens, the code that reports it updates b->val directly. */
+ if (b->val == NULL)
+ b->val = v;
+ value_contents (v);
+ value_release_to_mark (mark);
+
+ /* Look at each value on the value chain. */
+ for (; v; v = next)
+ {
+ /* If it's a memory location, and GDB actually needed
+ its contents to evaluate the expression, then we
+ must watch it. */
+ if (VALUE_LVAL (v) == lval_memory
+ && ! value_lazy (v))
+ {
+ struct type *vtype = check_typedef (value_type (v));
+
+ /* We only watch structs and arrays if user asked
+ for it explicitly, never if they just happen to
+ appear in the middle of some value chain. */
+ if (v == b->val
+ || (TYPE_CODE (vtype) != TYPE_CODE_STRUCT
+ && TYPE_CODE (vtype) != TYPE_CODE_ARRAY))
+ {
+ CORE_ADDR addr;
+ int len, type;
+ struct bp_location *loc, **tmp;
+
+ addr = VALUE_ADDRESS (v) + value_offset (v);
+ len = TYPE_LENGTH (value_type (v));
+ type = hw_write;
+ if (b->type == bp_read_watchpoint)
+ type = hw_read;
+ else if (b->type == bp_access_watchpoint)
+ type = hw_access;
+
+ loc = allocate_bp_location (b, bp_hardware_watchpoint);
+ for (tmp = &(b->loc); *tmp != NULL; tmp = &((*tmp)->next))
+ ;
+ *tmp = loc;
+ loc->address = addr;
+ loc->length = len;
+ loc->watchpoint_type = type;
+ }
+ }
+
+ next = value_next (v);
+ if (v != b->val)
+ value_free (v);
+ }
+
+ if (reparse && b->cond_string != NULL)
+ {
+ char *s = b->cond_string;
+ if (b->loc->cond)
+ {
+ xfree (b->loc->cond);
+ b->loc->cond = NULL;
+ }
+ b->loc->cond = parse_exp_1 (&s, b->exp_valid_block, 0);
+ }
+ }
+ else if (!within_current_scope)
+ {
+ printf_filtered (_("\
+Hardware watchpoint %d deleted because the program has left the block \n\
+in which its expression is valid.\n"),
+ b->number);
+ if (b->related_breakpoint)
+ b->related_breakpoint->disposition = disp_del_at_next_stop;
+ b->disposition = disp_del_at_next_stop;
+ }
+
+ /* Restore the selected frame. */
+ select_frame (frame_find_by_id (saved_frame_id));
}
+
/* Insert a low-level "breakpoint" of some type. BPT is the breakpoint.
Any error messages are printed to TMP_ERROR_STREAM; and DISABLED_BREAKS,
PROCESS_WARNING, and HW_BREAKPOINT_ERROR are used to report problems.
watchpoints. It's not clear that it's necessary... */
&& bpt->owner->disposition != disp_del_at_next_stop)
{
- /* FIXME drow/2003-09-08: This code sets multiple hardware watchpoints
- based on the expression. Ideally this should happen at a higher level,
- and there should be one bp_location for each computed address we
- must watch. As soon as a many-to-one mapping is available I'll
- convert this. */
-
- int within_current_scope;
- struct value *mark = value_mark ();
- struct value *v;
- struct frame_id saved_frame_id;
-
- /* Save the current frame's ID so we can restore it after
- evaluating the watchpoint expression on its own frame. */
- /* FIXME drow/2003-09-09: It would be nice if evaluate_expression
- took a frame parameter, so that we didn't have to change the
- selected frame. */
- saved_frame_id = get_frame_id (get_selected_frame (NULL));
-
- /* Determine if the watchpoint is within scope. */
- if (bpt->owner->exp_valid_block == NULL)
- within_current_scope = 1;
- else
- {
- struct frame_info *fi;
- fi = frame_find_by_id (bpt->owner->watchpoint_frame);
- within_current_scope = (fi != NULL);
- if (within_current_scope)
- select_frame (fi);
- }
-
- if (within_current_scope)
- {
- free_valchain (bpt);
-
- /* Evaluate the expression and cut the chain of values
- produced off from the value chain.
-
- Make sure the value returned isn't lazy; we use
- laziness to determine what memory GDB actually needed
- in order to compute the value of the expression. */
- v = evaluate_expression (bpt->owner->exp);
- value_contents (v);
- value_release_to_mark (mark);
-
- bpt->owner->val_chain = v;
- bpt->inserted = 1;
-
- /* Look at each value on the value chain. */
- for (; v; v = value_next (v))
- {
- /* If it's a memory location, and GDB actually needed
- its contents to evaluate the expression, then we
- must watch it. */
- if (VALUE_LVAL (v) == lval_memory
- && ! value_lazy (v))
- {
- struct type *vtype = check_typedef (value_type (v));
-
- /* We only watch structs and arrays if user asked
- for it explicitly, never if they just happen to
- appear in the middle of some value chain. */
- if (v == bpt->owner->val_chain
- || (TYPE_CODE (vtype) != TYPE_CODE_STRUCT
- && TYPE_CODE (vtype) != TYPE_CODE_ARRAY))
- {
- CORE_ADDR addr;
- int len, type;
-
- addr = VALUE_ADDRESS (v) + value_offset (v);
- len = TYPE_LENGTH (value_type (v));
- type = hw_write;
- if (bpt->owner->type == bp_read_watchpoint)
- type = hw_read;
- else if (bpt->owner->type == bp_access_watchpoint)
- type = hw_access;
-
- val = target_insert_watchpoint (addr, len, type);
- if (val == -1)
- {
- /* Don't exit the loop, try to insert
- every value on the value chain. That's
- because we will be removing all the
- watches below, and removing a
- watchpoint we didn't insert could have
- adverse effects. */
- bpt->inserted = 0;
- }
- val = 0;
- }
- }
- }
-
- if (bpt->owner->cond_string != NULL)
- {
- char *s = bpt->owner->cond_string;
- if (bpt->cond)
- {
- xfree (bpt->cond);
- bpt->cond = NULL;
- }
- bpt->cond = parse_exp_1 (&s, bpt->owner->exp_valid_block, 0);
- }
-
- /* Failure to insert a watchpoint on any memory value in the
- value chain brings us here. */
- if (!bpt->inserted)
- {
- remove_breakpoint (bpt, mark_uninserted);
- *hw_breakpoint_error = 1;
- fprintf_unfiltered (tmp_error_stream,
- "Could not insert hardware watchpoint %d.\n",
- bpt->owner->number);
- val = -1;
- }
- }
- else
- {
- printf_filtered (_("\
-Hardware watchpoint %d deleted because the program has left the block \n\
-in which its expression is valid.\n"),
- bpt->owner->number);
- if (bpt->owner->related_breakpoint)
- bpt->owner->related_breakpoint->disposition = disp_del_at_next_stop;
- bpt->owner->disposition = disp_del_at_next_stop;
- }
-
- /* Restore the selected frame. */
- select_frame (frame_find_by_id (saved_frame_id));
-
- return val;
+ val = target_insert_watchpoint (bpt->address,
+ bpt->length,
+ bpt->watchpoint_type);
+ bpt->inserted = (val != -1);
}
else if (bpt->owner->type == bp_catch_fork
void
insert_breakpoints (void)
{
+ struct breakpoint *bpt;
struct bp_location *b, *temp;
int error = 0;
int val = 0;
there was an error. */
fprintf_unfiltered (tmp_error_stream, "Warning:\n");
+ ALL_BREAKPOINTS (bpt)
+ if (is_hardware_watchpoint (bpt))
+ update_watchpoint (bpt, 0 /* don't reparse */);
+
ALL_BP_LOCATIONS_SAFE (b, temp)
{
if (!breakpoint_enabled (b->owner))
&& !valid_thread_id (b->owner->thread))
continue;
- /* FIXME drow/2003-10-07: This code should be pushed elsewhere when
- hardware watchpoints are split into multiple loc breakpoints. */
- if ((b->loc_type == bp_loc_hardware_watchpoint
- || b->owner->type == bp_watchpoint) && !b->owner->val)
- {
- struct value *val;
- val = evaluate_expression (b->owner->exp);
- release_value (val);
- if (value_lazy (val))
- value_fetch_lazy (val);
- b->owner->val = val;
- }
-
val = insert_bp_location (b, tmp_error_stream,
&disabled_breaks, &process_warning,
&hw_breakpoint_error);
error = val;
}
+ /* If we failed to insert all locations of a watchpoint,
+ remove them, as half-inserted watchpoint is of limited use. */
+ ALL_BREAKPOINTS (bpt)
+ {
+ int some_failed = 0;
+ struct bp_location *loc;
+
+ if (!is_hardware_watchpoint (bpt))
+ continue;
+
+ if (bpt->enable_state != bp_enabled)
+ continue;
+
+ for (loc = bpt->loc; loc; loc = loc->next)
+ if (!loc->inserted)
+ {
+ some_failed = 1;
+ break;
+ }
+ if (some_failed)
+ {
+ for (loc = bpt->loc; loc; loc = loc->next)
+ if (loc->inserted)
+ remove_breakpoint (loc, mark_uninserted);
+
+ hw_breakpoint_error = 1;
+ fprintf_unfiltered (tmp_error_stream,
+ "Could not insert hardware watchpoint %d.\n",
+ bpt->number);
+ error = -1;
+ }
+ }
+
if (error)
{
/* If a hardware breakpoint or watchpoint was inserted, add a
return val;
b->inserted = (is == mark_inserted);
}
- else if (b->loc_type == bp_loc_hardware_watchpoint
- && breakpoint_enabled (b->owner)
- && !b->duplicate)
+ else if (b->loc_type == bp_loc_hardware_watchpoint)
{
struct value *v;
struct value *n;
b->inserted = (is == mark_inserted);
- /* Walk down the saved value chain. */
- for (v = b->owner->val_chain; v; v = value_next (v))
- {
- /* For each memory reference remove the watchpoint
- at that address. */
- if (VALUE_LVAL (v) == lval_memory
- && ! value_lazy (v))
- {
- struct type *vtype = check_typedef (value_type (v));
-
- if (v == b->owner->val_chain
- || (TYPE_CODE (vtype) != TYPE_CODE_STRUCT
- && TYPE_CODE (vtype) != TYPE_CODE_ARRAY))
- {
- CORE_ADDR addr;
- int len, type;
+ val = target_remove_watchpoint (b->address, b->length,
+ b->watchpoint_type);
- addr = VALUE_ADDRESS (v) + value_offset (v);
- len = TYPE_LENGTH (value_type (v));
- type = hw_write;
- if (b->owner->type == bp_read_watchpoint)
- type = hw_read;
- else if (b->owner->type == bp_access_watchpoint)
- type = hw_access;
-
- val = target_remove_watchpoint (addr, len, type);
- if (val == -1)
- b->inserted = 1;
- val = 0;
- }
- }
- }
/* Failure to remove any of the hardware watchpoints comes here. */
if ((is == mark_uninserted) && (b->inserted))
warning (_("Could not remove hardware watchpoint %d."),
|| b->type == bp_read_watchpoint
|| b->type == bp_access_watchpoint)
{
+ struct bp_location *loc;
struct value *v;
b->watchpoint_triggered = watch_triggered_no;
- for (v = b->val_chain; v; v = value_next (v))
- {
- if (VALUE_LVAL (v) == lval_memory && ! value_lazy (v))
- {
- struct type *vtype = check_typedef (value_type (v));
-
- if (v == b->val_chain
- || (TYPE_CODE (vtype) != TYPE_CODE_STRUCT
- && TYPE_CODE (vtype) != TYPE_CODE_ARRAY))
- {
- CORE_ADDR vaddr;
-
- vaddr = VALUE_ADDRESS (v) + value_offset (v);
- /* Exact match not required. Within range is
- sufficient. */
- if (addr >= vaddr
- && addr < vaddr + TYPE_LENGTH (value_type (v)))
- {
- b->watchpoint_triggered = watch_triggered_yes;
- break;
- }
- }
- }
- }
+ for (loc = b->loc; loc; loc = loc->next)
+ /* Exact match not required. Within range is
+ sufficient. */
+ if (addr >= loc->address
+ && addr < loc->address + loc->length)
+ {
+ b->watchpoint_triggered = watch_triggered_yes;
+ break;
+ }
}
return 1;
&& !inferior_has_execd (PIDGET (inferior_ptid), &b->exec_pathname))
continue;
+ /* For hardware watchpoints, we look only at the first location.
+ The watchpoint_check function will work on entire expression,
+ not the individual locations. For read watchopints, the
+ watchpoints_triggered function have checked all locations
+ alrea
+ */
+ if (b->type == bp_hardware_watchpoint && bl != b->loc)
+ continue;
+
/* Come here if it's a watchpoint, or if the break address matches */
bs = bpstat_alloc (bl, bs); /* Alloc a bpstat to explain stop */
|| bs->breakpoint_at->owner->type == bp_read_watchpoint
|| bs->breakpoint_at->owner->type == bp_access_watchpoint))
{
+ /* remove/insert can invalidate bs->breakpoint_at, if this
+ location is no longer used by the watchpoint. Prevent
+ further code from trying to use it. */
+ bs->breakpoint_at = NULL;
remove_breakpoints ();
insert_breakpoints ();
break;
disabled, we print it as if it had
several locations, since otherwise it's hard to
represent "breakpoint enabled, location disabled"
- situation. */
+ situation.
+ Note that while hardware watchpoints have
+ several locations internally, that's no a property
+ exposed to user. */
if (b->loc
+ && !is_hardware_watchpoint (b)
&& (b->loc->next || !b->loc->enabled)
- && !ui_out_is_mi_like_p (uiout))
+ && !ui_out_is_mi_like_p (uiout))
{
struct bp_location *loc;
int n = 1;
{
if (loc->inserted)
remove_breakpoint (loc, mark_inserted);
-
- free_valchain (loc);
-
+
if (loc->cond)
xfree (loc->cond);
Don't do anything about disabled watchpoints, since they will
be reevaluated again when enabled. */
-
- if (!breakpoint_enabled (b))
- break;
-
- if (b->exp_valid_block == NULL
- || frame_find_by_id (b->watchpoint_frame) != NULL)
- {
- if (b->exp)
- {
- xfree (b->exp);
- b->exp = NULL;
- }
- s = b->exp_string;
- b->exp = parse_exp_1 (&s, b->exp_valid_block, 0);
-
- /* Since we reparsed expression, we need to update the
- value. I'm not aware of any way a single solib load or unload
- can change a valid value into different valid value, but:
- - even if the value is no longer valid, we have to record
- this fact, so that when it becomes valid we reports this
- as value change
- - unloaded followed by load can change the value for sure.
-
- We set value to NULL, and insert_breakpoints will
- update the value. */
- if (b->val)
- value_free (b->val);
- b->val = NULL;
-
- /* Loading of new shared library change the meaning of
- watchpoint condition. However, insert_bp_location will
- recompute watchpoint condition anyway, nothing to do here. */
- }
+ update_watchpoint (b, 1 /* reparse */);
break;
/* We needn't really do anything to reset these, since the mask
that requests them is unaffected by e.g., new libraries being
projects / binutils-gdb.git / commitdiff