static void
watch_command PARAMS ((char *, int));
+static int
+can_use_hardware_watchpoint PARAMS ((struct breakpoint *));
+
static void
tbreak_command PARAMS ((char *, int));
static void
set_breakpoint_count PARAMS ((int));
+static int
+remove_breakpoint PARAMS ((struct breakpoint *));
extern int addressprint; /* Print machine addresses? */
extern int demangle; /* Print de-mangled symbol names? */
b? (tmp=b->next, 1): 0; \
b = tmp)
+/* By default no support for hardware watchpoints is assumed. */
+#ifndef TARGET_CAN_USE_HARDWARE_WATCHPOINT
+#define TARGET_CAN_USE_HARDWARE_WATCHPOINT(B) 0
+#define target_remove_watchpoint(ADDR,LEN) -1
+#define target_insert_watchpoint(ADDR,LEN) -1
+#endif
+
/* Chain of all breakpoints defined. */
static struct breakpoint *breakpoint_chain;
ALL_BREAKPOINTS (b)
{
- if (b->type == bp_watchpoint || !b->inserted)
+ if (b->type == bp_watchpoint
+ || b->type == bp_hardware_watchpoint
+ || !b->inserted)
continue;
else if (b->address + memory_breakpoint_size <= memaddr)
/* The breakpoint is entirely before the chunk of memory
ALL_BREAKPOINTS (b)
if (b->type != bp_watchpoint
+ && b->type != bp_hardware_watchpoint
&& b->enable != disabled
&& ! b->inserted
&& ! b->duplicate)
else
b->inserted = 1;
}
+ else if (b->type == bp_hardware_watchpoint
+ && b->enable == enabled
+ && ! b->inserted
+ && ! b->duplicate)
+ {
+ FRAME saved_frame;
+ int saved_level, within_current_scope;
+ value_ptr mark = value_mark ();
+ value_ptr v;
+
+ /* Save the current frame and level so we can restore it after
+ evaluating the watchpoint expression on its own frame. */
+ saved_frame = selected_frame;
+ saved_level = selected_frame_level;
+
+ /* Determine if the watchpoint is within scope. */
+ if (b->exp_valid_block == NULL)
+ within_current_scope = 1;
+ else
+ {
+ FRAME fr = find_frame_addr_in_frame_chain (b->watchpoint_frame);
+ within_current_scope = (fr != NULL);
+ if (within_current_scope)
+ select_frame (fr, -1);
+ }
+
+ if (within_current_scope)
+ {
+ /* Evaluate the expression and cut the chain of values
+ produced off from the value chain. */
+ v = evaluate_expression (b->exp);
+ value_release_to_mark (mark);
+
+ b->val_chain = v;
+ b->inserted = 1;
+
+ /* Look at each value on the value chain. */
+ for ( ; v; v=v->next)
+ {
+ /* If it's a memory location, then we must watch it. */
+ if (v->lval == lval_memory)
+ {
+ int addr, len;
+
+ addr = VALUE_ADDRESS (v) + VALUE_OFFSET (v);
+ len = TYPE_LENGTH (VALUE_TYPE (v));
+ val = target_insert_watchpoint (addr, len);
+ if (val == -1)
+ {
+ b->inserted = 0;
+ break;
+ }
+ val = 0;
+ }
+ }
+ /* Failure to insert a watchpoint on any memory value in the
+ value chain brings us here. */
+ if (!b->inserted)
+ warning ("Hardware watchpoint %d: Could not insert watchpoint\n",
+ b->number);
+ }
+ else
+ {
+ printf_filtered ("\
+Hardware watchpoint %d deleted because the program has left the block in\n\
+which its expression is valid.\n", b->number);
+ if (b->related_breakpoint)
+ delete_breakpoint (b->related_breakpoint);
+ delete_breakpoint (b);
+ }
+
+ /* Restore the frame and level. */
+ select_frame (saved_frame, saved_level);
+ }
if (disabled_breaks)
printf_filtered ("\n");
return val;
}
+
int
remove_breakpoints ()
{
int val;
ALL_BREAKPOINTS (b)
- if (b->type != bp_watchpoint && b->inserted)
- {
- val = target_remove_breakpoint(b->address, b->shadow_contents);
- if (val)
- return val;
- b->inserted = 0;
- }
+ {
+ if (b->inserted)
+ {
+ val = remove_breakpoint (b);
+ if (val != 0)
+ return val;
+ }
+ }
+ return 0;
+}
+
+static int
+remove_breakpoint (b)
+ struct breakpoint *b;
+{
+ int val;
+
+ if (b->type != bp_watchpoint
+ && b->type != bp_hardware_watchpoint)
+ {
+ val = target_remove_breakpoint(b->address, b->shadow_contents);
+ if (val)
+ return val;
+ b->inserted = 0;
+ }
+ else if (b->type == bp_hardware_watchpoint
+ && b->enable == enabled
+ && ! b->duplicate)
+ {
+ value_ptr v, n;
+
+ b->inserted = 0;
+ /* Walk down the saved value chain. */
+ for (v = b->val_chain; v; v = v->next)
+ {
+ /* For each memory reference remove the watchpoint
+ at that address. */
+ if (v->lval == lval_memory)
+ {
+ int addr, len;
+
+ addr = VALUE_ADDRESS (v) + VALUE_OFFSET (v);
+ len = TYPE_LENGTH (VALUE_TYPE (v));
+ val = target_remove_watchpoint (addr, len);
+ if (val == -1)
+ b->inserted = 1;
+ val = 0;
+ }
+ }
+ /* Failure to remove any of the hardware watchpoints comes here. */
+ if (b->inserted)
+ error ("Hardware watchpoint %d: Could not remove watchpoint\n",
+ b->number);
+
+ /* Free the saved value chain. We will construct a new one
+ the next time the watchpoint is inserted. */
+ for (v = b->val_chain; v; v = n)
+ {
+ n = v->next;
+ value_free (v);
+ }
+ b->val_chain = NULL;
+ }
return 0;
}
get rid of it. */
if (b->type == bp_call_dummy)
delete_breakpoint (b);
+
+ /* Likewise for scope breakpoints. */
+ if (b->type == bp_watchpoint_scope)
+ delete_breakpoint (b);
+
+ /* Likewise for watchpoints on local expressions. */
+ if ((b->type == bp_watchpoint || b->type == bp_hardware_watchpoint)
+ && b->exp_valid_block != NULL)
+ delete_breakpoint (b);
}
}
which has since been deleted. */
if (bs->breakpoint_at == NULL
|| (bs->breakpoint_at->type != bp_breakpoint
- && bs->breakpoint_at->type != bp_watchpoint))
+ && bs->breakpoint_at->type != bp_watchpoint
+ && bs->breakpoint_at->type != bp_hardware_watchpoint))
return 0;
if (bs->breakpoint_at->type == bp_breakpoint)
return bs;
}
\f
-/* Return the frame which we can use to evaluate the expression
- whose valid block is valid_block, or NULL if not in scope.
-
- This whole concept is probably not the way to do things (it is incredibly
- slow being the main reason, not to mention fragile (e.g. the sparc
- frame pointer being fetched as 0 bug causes it to stop)). Instead,
- introduce a version of "struct frame" which survives over calls to the
- inferior, but which is better than FRAME_ADDR in the sense that it lets
- us evaluate expressions relative to that frame (on some machines, it
- can just be a FRAME_ADDR). Save one of those instead of (or in addition
- to) the exp_valid_block, and then use it to evaluate the watchpoint
- expression, with no need to do all this backtracing every time.
-
- Or better yet, what if it just copied the struct frame and its next
- frame? Off the top of my head, I would think that would work
- because things like (a29k) rsize and msize, or (sparc) bottom just
- depend on the frame, and aren't going to be different just because
- the inferior has done something. Trying to recalculate them
- strikes me as a lot of work, possibly even impossible. Saving the
- next frame is needed at least on a29k, where get_saved_register
- uses fi->next->saved_msp. For figuring out whether that frame is
- still on the stack, I guess this needs to be machine-specific (e.g.
- a29k) but I think
-
- read_fp () INNER_THAN watchpoint_frame->frame
-
- would generally work.
-
- Of course the scope of the expression could be less than a whole
- function; perhaps if the innermost frame is the one which the
- watchpoint is relative to (another machine-specific thing, usually
-
- FRAMELESS_FUNCTION_INVOCATION (get_current_frame(), fromleaf)
- read_fp () == wp_frame->frame
- && !fromleaf
-
- ), *then* it could do a
-
- contained_in (get_current_block (), wp->exp_valid_block).
-
- */
-
-FRAME
-within_scope (valid_block)
- struct block *valid_block;
-{
- FRAME fr = get_current_frame ();
- struct frame_info *fi = get_frame_info (fr);
- CORE_ADDR func_start;
-
- /* If caller_pc_valid is true, we are stepping through
- a function prologue, which is bounded by callee_func_start
- (inclusive) and callee_prologue_end (exclusive).
- caller_pc is the pc of the caller.
-
- Yes, this is hairy. */
- static int caller_pc_valid = 0;
- static CORE_ADDR caller_pc;
- static CORE_ADDR callee_func_start;
- static CORE_ADDR callee_prologue_end;
-
- find_pc_partial_function (fi->pc, (PTR)NULL, &func_start, (CORE_ADDR *)NULL);
- func_start += FUNCTION_START_OFFSET;
- if (fi->pc == func_start)
- {
- /* We just called a function. The only other case I
- can think of where the pc would equal the pc of the
- start of a function is a frameless function (i.e.
- no prologue) where we branch back to the start
- of the function. In that case, SKIP_PROLOGUE won't
- find one, and we'll clear caller_pc_valid a few lines
- down. */
- caller_pc_valid = 1;
- caller_pc = SAVED_PC_AFTER_CALL (fr);
- callee_func_start = func_start;
- SKIP_PROLOGUE (func_start);
- callee_prologue_end = func_start;
- }
- if (caller_pc_valid)
- {
- if (fi->pc < callee_func_start
- || fi->pc >= callee_prologue_end)
- caller_pc_valid = 0;
- }
-
- if (contained_in (block_for_pc (caller_pc_valid
- ? caller_pc
- : fi->pc),
- valid_block))
- {
- return fr;
- }
- fr = get_prev_frame (fr);
-
- /* If any active frame is in the exp_valid_block, then it's
- OK. Note that this might not be the same invocation of
- the exp_valid_block that we were watching a little while
- ago, or the same one as when the watchpoint was set (e.g.
- we are watching a local variable in a recursive function.
- When we return from a recursive invocation, then we are
- suddenly watching a different instance of the variable).
-
- At least for now I am going to consider this a feature. */
- for (; fr != NULL; fr = get_prev_frame (fr))
- {
- fi = get_frame_info (fr);
- if (contained_in (block_for_pc (fi->pc),
- valid_block))
- {
- return fr;
- }
- }
- return NULL;
-}
+
/* Possible return values for watchpoint_check (this can't be an enum
because of check_errors). */
-/* The watchpoint has been disabled. */
-#define WP_DISABLED 1
+/* The watchpoint has been deleted. */
+#define WP_DELETED 1
/* The value has changed. */
#define WP_VALUE_CHANGED 2
/* The value has not changed. */
char *p;
{
bpstat bs = (bpstat) p;
- FRAME fr;
+ struct breakpoint *b;
+ FRAME saved_frame, fr;
+ int within_current_scope, saved_level;
+
+ /* Save the current frame and level so we can restore it after
+ evaluating the watchpoint expression on its own frame. */
+ saved_frame = selected_frame;
+ saved_level = selected_frame_level;
- int within_current_scope;
if (bs->breakpoint_at->exp_valid_block == NULL)
within_current_scope = 1;
else
{
- fr = within_scope (bs->breakpoint_at->exp_valid_block);
- within_current_scope = fr != NULL;
+ fr = find_frame_addr_in_frame_chain (bs->breakpoint_at->watchpoint_frame);
+ within_current_scope = (fr != NULL);
if (within_current_scope)
/* If we end up stopping, the current frame will get selected
in normal_stop. So this call to select_frame won't affect
bs->old_val = bs->breakpoint_at->val;
bs->breakpoint_at->val = new_val;
/* We will stop here */
+ select_frame (saved_frame, saved_level);
return WP_VALUE_CHANGED;
}
else
/* Nothing changed, don't do anything. */
value_free_to_mark (mark);
/* We won't stop here */
+ select_frame (saved_frame, saved_level);
return WP_VALUE_NOT_CHANGED;
}
}
So we can't even detect the first assignment to it and
watch after that (since the garbage may or may not equal
the first value assigned). */
- bs->breakpoint_at->enable = disabled;
printf_filtered ("\
-Watchpoint %d disabled because the program has left the block in\n\
+Watchpoint %d deleted because the program has left the block in\n\
which its expression is valid.\n", bs->breakpoint_at->number);
- return WP_DISABLED;
+ if (bs->breakpoint_at->related_breakpoint)
+ delete_breakpoint (bs->breakpoint_at->related_breakpoint);
+ delete_breakpoint (bs->breakpoint_at);
+
+ select_frame (saved_frame, saved_level);
+ return WP_DELETED;
}
}
if (b->enable == disabled)
continue;
- if (b->type != bp_watchpoint && b->address != bp_addr)
+ if (b->type != bp_watchpoint
+ && b->type != bp_hardware_watchpoint
+ && b->address != bp_addr)
continue;
- if (b->type != bp_watchpoint && not_a_breakpoint)
+ if (b->type != bp_watchpoint
+ && b->type != bp_hardware_watchpoint
+ && not_a_breakpoint)
continue;
/* Come here if it's a watchpoint, or if the break address matches */
bs->stop = 1;
bs->print = 1;
- if (b->type == bp_watchpoint)
+ if (b->type == bp_watchpoint || b->type == bp_hardware_watchpoint)
{
static char message1[] =
"Error evaluating expression for watchpoint %d\n";
switch (catch_errors (watchpoint_check, (char *) bs, message,
RETURN_MASK_ALL))
{
- case WP_DISABLED:
+ case WP_DELETED:
/* We've already printed what needs to be printed. */
bs->print_it = print_it_done;
/* Stop. */
/* FALLTHROUGH */
case 0:
/* Error from catch_errors. */
- b->enable = disabled;
- printf_filtered ("Watchpoint %d disabled.\n", b->number);
+ printf_filtered ("Watchpoint %d deleted.\n", b->number);
+ if (b->related_breakpoint)
+ delete_breakpoint (b->related_breakpoint);
+ delete_breakpoint (b);
/* We've already printed what needs to be printed. */
bs->print_it = print_it_done;
+
/* Stop. */
break;
}
}
}
#endif /* DECR_PC_AFTER_BREAK != 0. */
+
+ /* The value of a hardware watchpoint hasn't changed, but the
+ intermediate memory locations we are watching may have. */
+ if (bs && ! bs->stop
+ && bs->breakpoint_at->type == bp_hardware_watchpoint)
+ {
+ remove_breakpoints ();
+ insert_breakpoints ();
+ }
return bs;
}
\f
bs_class = bp_nostop;
break;
case bp_watchpoint:
+ case bp_hardware_watchpoint:
if (bs->stop)
{
if (bs->print)
case bp_through_sigtramp:
bs_class = through_sig;
break;
+ case bp_watchpoint_scope:
+ bs_class = bp_nostop;
+ break;
+
case bp_call_dummy:
/* Make sure the action is stop (silent or noisy), so infrun.c
pops the dummy frame. */
CORE_ADDR last_addr = (CORE_ADDR)-1;
int found_a_breakpoint = 0;
static char *bptypes[] = {"breakpoint", "until", "finish", "watchpoint",
- "longjmp", "longjmp resume", "step resume",
- "call dummy" };
+ "hardware watchpoint", "longjmp",
+ "longjmp resume", "step resume",
+ "watchpoint scope", "call dummy" };
static char *bpdisps[] = {"del", "dis", "keep"};
static char bpenables[] = "ny";
char wrap_indent[80];
/* We only print out user settable breakpoints unless the allflag is set. */
if (!allflag
&& b->type != bp_breakpoint
- && b->type != bp_watchpoint)
+ && b->type != bp_watchpoint
+ && b->type != bp_hardware_watchpoint)
continue;
if (!found_a_breakpoint++)
switch (b->type)
{
case bp_watchpoint:
+ case bp_hardware_watchpoint:
print_expression (b->exp, gdb_stdout);
break;
case bp_longjmp_resume:
case bp_step_resume:
case bp_through_sigtramp:
+ case bp_watchpoint_scope:
case bp_call_dummy:
if (addressprint)
printf_filtered ("%s ", local_hex_string_custom ((unsigned long) b->address, "08l"));
printf_filtered ("Watchpoint %d: ", b->number);
print_expression (b->exp, gdb_stdout);
break;
+ case bp_hardware_watchpoint:
+ printf_filtered ("Hardware watchpoint %d: ", b->number);
+ print_expression (b->exp, gdb_stdout);
+ break;
case bp_breakpoint:
printf_filtered ("Breakpoint %d at ", b->number);
print_address_numeric (b->address, gdb_stdout);
case bp_step_resume:
case bp_through_sigtramp:
case bp_call_dummy:
+ case bp_watchpoint_scope:
break;
}
printf_filtered ("\n");
struct expression *exp;
struct block *exp_valid_block;
struct value *val;
+ FRAME frame, prev_frame;
sal.pc = 0;
sal.symtab = NULL;
b = set_raw_breakpoint (sal);
set_breakpoint_count (breakpoint_count + 1);
b->number = breakpoint_count;
- b->type = bp_watchpoint;
b->disposition = donttouch;
b->exp = exp;
b->exp_valid_block = exp_valid_block;
b->cond = 0;
b->cond_string = NULL;
b->exp_string = savestring (arg, strlen (arg));
+
+ frame = block_innermost_frame (exp_valid_block);
+ if (frame)
+ {
+ prev_frame = get_prev_frame (frame);
+ b->watchpoint_frame = FRAME_FP (frame);
+ }
+ else
+ b->watchpoint_frame = NULL;
+
+ if (can_use_hardware_watchpoint (b))
+ b->type = bp_hardware_watchpoint;
+ else
+ b->type = bp_watchpoint;
+
+ /* If the expression is "local", then set up a "watchpoint scope"
+ breakpoint at the point where we've left the scope of the watchpoint
+ expression. */
+ if (innermost_block)
+ {
+ struct breakpoint *scope_breakpoint;
+ struct symtab_and_line scope_sal;
+
+ if (prev_frame)
+ {
+ scope_sal.pc = get_frame_pc (prev_frame);
+ scope_sal.symtab = NULL;
+ scope_sal.line = 0;
+
+ scope_breakpoint = set_raw_breakpoint (scope_sal);
+ set_breakpoint_count (breakpoint_count + 1);
+ scope_breakpoint->number = breakpoint_count;
+
+ scope_breakpoint->type = bp_watchpoint_scope;
+ scope_breakpoint->enable = enabled;
+
+ /* Automatically delete the breakpoint when it hits. */
+ scope_breakpoint->disposition = delete;
+
+ /* Only break in the proper frame (help with recursion). */
+ scope_breakpoint->frame = prev_frame->frame;
+
+ /* Set the address at which we will stop. */
+ scope_breakpoint->address = get_frame_pc (prev_frame);
+
+ /* The scope breakpoint is related to the watchpoint. We
+ will need to act on them together. */
+ b->related_breakpoint = scope_breakpoint;
+ }
+ }
+
mention (b);
}
+
+/* Return nonzero if the watchpoint described by B can be handled
+ completely in hardware. If the watchpoint can not be handled
+ in hardware return zero. */
+
+static int
+can_use_hardware_watchpoint (b)
+ struct breakpoint *b;
+{
+ value_ptr mark = value_mark ();
+ value_ptr v = evaluate_expression (b->exp);
+ int found_memory = 0;
+
+ /* Make sure all the intermediate values are in memory. Also make sure
+ we found at least one memory expression. Guards against watch 0x12345,
+ which is meaningless, but could cause errors if one tries to insert a
+ hardware watchpoint for the constant expression. */
+ for ( ; v != mark; v = v->next)
+ {
+ if (!(v->lval == lval_memory)
+ || v->lval == not_lval
+ || (v->lval != not_lval
+ && v->modifiable == false))
+ return 0;
+ else
+ if (v->lval == lval_memory)
+ found_memory = 1;
+ }
+
+ /* The expression itself looks suitable for using a hardware
+ watchpoint, but give the target machine a chance to reject it. */
+ return found_memory && TARGET_CAN_USE_HARDWARE_WATCHPOINT (b);
+}
+
\f
/*
* Helper routine for the until_command routine in infcmd.c. Here
ALL_BREAKPOINTS (b)
while (b->next
&& b->next->type != bp_watchpoint
+ && b->next->type != bp_hardware_watchpoint
&& (sal.pc
? b->next->address == sal.pc
: (b->next->source_file != NULL
register bpstat bs;
if (bpt->inserted)
- target_remove_breakpoint(bpt->address, bpt->shadow_contents);
-
+ remove_breakpoint (bpt);
+
if (breakpoint_chain == bpt)
breakpoint_chain = bpt->next;
check_duplicates (bpt->address);
/* If this breakpoint was inserted, and there is another breakpoint
at the same address, we need to insert the other breakpoint. */
- if (bpt->inserted)
+ if (bpt->inserted
+ && bpt->type != bp_hardware_watchpoint)
{
ALL_BREAKPOINTS (b)
if (b->address == bpt->address
break;
case bp_watchpoint:
+ case bp_hardware_watchpoint:
innermost_block = NULL;
/* The issue arises of what context to evaluate this in. The same
one as when it was set, but what does that mean when symbols have
case bp_finish:
case bp_longjmp:
case bp_longjmp_resume:
+ case bp_watchpoint_scope:
case bp_call_dummy:
delete_breakpoint (b);
break;
ALL_BREAKPOINTS (b)
if (b->number == num)
{
+ struct breakpoint *related_breakpoint = b->related_breakpoint;
function (b);
+ if (related_breakpoint)
+ function (related_breakpoint);
goto win;
}
printf_unfiltered ("No breakpoint number %d.\n", num);
printf_unfiltered ("breakpoint #%d enabled\n", bpt->number);
check_duplicates (bpt->address);
- if (bpt->type == bp_watchpoint)
+ if (bpt->type == bp_watchpoint || bpt->type == bp_hardware_watchpoint)
{
if (bpt->exp_valid_block != NULL)
{
- FRAME fr = within_scope (bpt->exp_valid_block);
+ FRAME fr = find_frame_addr_in_frame_chain (bpt->watchpoint_frame);
if (fr == NULL)
{
printf_filtered ("\
bpt->enable = disabled;
return;
}
+
save_selected_frame = selected_frame;
save_selected_frame_level = selected_frame_level;
select_frame (fr, -1);
{
case bp_breakpoint:
case bp_watchpoint:
+ case bp_hardware_watchpoint:
enable_breakpoint (bpt);
default:
continue;
disable_breakpoint (bpt)
struct breakpoint *bpt;
{
+ /* Never disable a watchpoint scope breakpoint; we want to
+ hit them when we leave scope so we can delete both the
+ watchpoint and its scope breakpoint at that time. */
+ if (bpt->type == bp_watchpoint_scope)
+ return;
+
bpt->enable = disabled;
if (xgdb_verbose && bpt->type == bp_breakpoint)
{
case bp_breakpoint:
case bp_watchpoint:
+ case bp_hardware_watchpoint:
disable_breakpoint (bpt);
default:
continue;
projects / binutils-gdb.git / commitdiff