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-rw-r--r--gdb/infrun.c709
1 files changed, 339 insertions, 370 deletions
diff --git a/gdb/infrun.c b/gdb/infrun.c
index 58e3aee..30dfd72 100644
--- a/gdb/infrun.c
+++ b/gdb/infrun.c
@@ -138,12 +138,6 @@ static void
sig_print_header PARAMS ((void));
static void
-remove_step_breakpoint PARAMS ((void));
-
-static void
-insert_step_breakpoint PARAMS ((void));
-
-static void
resume_cleanups PARAMS ((int));
static int
@@ -216,19 +210,6 @@ static int breakpoints_inserted;
static struct symbol *step_start_function;
-/* Nonzero => address for special breakpoint for resuming stepping. */
-
-static CORE_ADDR step_resume_break_address;
-
-/* Pointer to orig contents of the byte where the special breakpoint is. */
-
-static char step_resume_break_shadow[BREAKPOINT_MAX];
-
-/* Nonzero means the special breakpoint is a duplicate
- so it has not itself been inserted. */
-
-static int step_resume_break_duplicate;
-
/* Nonzero if we are expecting a trace trap and should proceed from it. */
static int trap_expected;
@@ -335,7 +316,6 @@ clear_proceed_status ()
step_range_end = 0;
step_frame_address = 0;
step_over_calls = -1;
- step_resume_break_address = 0;
stop_after_trap = 0;
stop_soon_quietly = 0;
proceed_to_finish = 0;
@@ -468,7 +448,14 @@ init_wait_for_inferior ()
stop_signal = 0; /* Don't confuse first call to proceed(). */
}
-
+static void
+delete_breakpoint_current_contents (arg)
+ PTR arg;
+{
+ struct breakpoint **breakpointp = (struct breakpoint **)arg;
+ if (*breakpointp != NULL)
+ delete_breakpoint (*breakpointp);
+}
/* Wait for control to return from inferior to debugger.
If inferior gets a signal, we may decide to start it up again
@@ -479,6 +466,7 @@ init_wait_for_inferior ()
void
wait_for_inferior ()
{
+ struct cleanup *old_cleanups;
WAITTYPE w;
int another_trap;
int random_signal;
@@ -486,13 +474,15 @@ wait_for_inferior ()
CORE_ADDR stop_func_start;
char *stop_func_name;
CORE_ADDR prologue_pc, tmp;
- int stop_step_resume_break;
struct symtab_and_line sal;
int remove_breakpoints_on_following_step = 0;
int current_line;
int handling_longjmp = 0; /* FIXME */
struct symtab *symtab;
+ struct breakpoint *step_resume_breakpoint = NULL;
+ old_cleanups = make_cleanup (delete_breakpoint_current_contents,
+ &step_resume_breakpoint);
sal = find_pc_line(prev_pc, 0);
current_line = sal.line;
@@ -577,7 +567,7 @@ wait_for_inferior ()
stop_pc = read_pc ();
set_current_frame ( create_new_frame (read_fp (),
read_pc ()));
-
+
stop_frame_address = FRAME_FP (get_current_frame ());
stop_sp = read_sp ();
stop_func_start = 0;
@@ -591,7 +581,6 @@ wait_for_inferior ()
stop_step = 0;
stop_stack_dummy = 0;
stop_print_frame = 1;
- stop_step_resume_break = 0;
random_signal = 0;
stopped_by_random_signal = 0;
breakpoints_failed = 0;
@@ -634,11 +623,11 @@ wait_for_inferior ()
if just proceeded over a breakpoint.
However, if we are trying to proceed over a breakpoint
- and end up in sigtramp, then step_resume_break_address
+ and end up in sigtramp, then step_resume_breakpoint
will be set and we should check whether we've hit the
step breakpoint. */
if (stop_signal == SIGTRAP && trap_expected
- && step_resume_break_address == 0)
+ && step_resume_breakpoint == NULL)
bpstat_clear (&stop_bpstat);
else
{
@@ -652,47 +641,28 @@ wait_for_inferior ()
the address of the breakpoint before the current pc. */
if (prev_pc == stop_pc - DECR_PC_AFTER_BREAK
|| !step_range_end
- || step_resume_break_address
+ || step_resume_breakpoint != NULL
|| handling_longjmp /* FIXME */)
#endif /* DECR_PC_AFTER_BREAK not zero */
{
- /* See if we stopped at the special breakpoint for
- stepping over a subroutine call. If both are zero,
- this wasn't the reason for the stop. */
- if (step_resume_break_address
- && stop_pc - DECR_PC_AFTER_BREAK
- == step_resume_break_address)
- {
- stop_step_resume_break = 1;
- if (DECR_PC_AFTER_BREAK)
- {
- stop_pc -= DECR_PC_AFTER_BREAK;
- write_pc (stop_pc);
- }
- }
- else
- {
- stop_bpstat =
- bpstat_stop_status (&stop_pc, stop_frame_address);
- /* Following in case break condition called a
- function. */
- stop_print_frame = 1;
- }
+ stop_bpstat =
+ bpstat_stop_status (&stop_pc, stop_frame_address);
+ /* Following in case break condition called a
+ function. */
+ stop_print_frame = 1;
}
}
-
+
if (stop_signal == SIGTRAP)
random_signal
= !(bpstat_explains_signal (stop_bpstat)
|| trap_expected
- || stop_step_resume_break
|| PC_IN_CALL_DUMMY (stop_pc, stop_sp, stop_frame_address)
- || (step_range_end && !step_resume_break_address));
+ || (step_range_end && step_resume_breakpoint == NULL));
else
{
random_signal
= !(bpstat_explains_signal (stop_bpstat)
- || stop_step_resume_break
/* End of a stack dummy. Some systems (e.g. Sony
news) give another signal besides SIGTRAP,
so check here as well as above. */
@@ -704,10 +674,10 @@ wait_for_inferior ()
}
else
random_signal = 1;
-
+
/* For the program's own signals, act according to
the signal handling tables. */
-
+
if (random_signal)
{
/* Signal not for debugging purposes. */
@@ -747,132 +717,103 @@ wait_for_inferior ()
if (signal_program[stop_signal] == 0)
stop_signal = 0;
- /* Note that virtually all the code below does `if !random_signal'.
- Perhaps this code should end with a goto or continue. At least
- one (now fixed) bug was caused by this -- a !random_signal was
- missing in one of the tests below. */
+ /* I'm not sure whether this needs to be check_sigtramp2 or
+ whether it could/should be keep_going. */
+ goto check_sigtramp2;
}
/* Handle cases caused by hitting a breakpoint. */
+ {
+ CORE_ADDR jmp_buf_pc;
+ struct bpstat_what what = bpstat_what (stop_bpstat);
- if (!random_signal)
- {
- CORE_ADDR jmp_buf_pc;
- enum bpstat_what what = bpstat_what (stop_bpstat);
-
- switch (what)
- {
- case BPSTAT_WHAT_SET_LONGJMP_RESUME:
- /* If we hit the breakpoint at longjmp, disable it for the
- duration of this command. Then, install a temporary
- breakpoint at the target of the jmp_buf. */
- disable_longjmp_breakpoint();
- remove_breakpoints ();
- breakpoints_inserted = 0;
- if (!GET_LONGJMP_TARGET(&jmp_buf_pc)) goto keep_going;
-
- /* Need to blow away step-resume breakpoint, as it
- interferes with us */
- remove_step_breakpoint ();
- step_resume_break_address = 0;
- stop_step_resume_break = 0;
+ switch (what.main_action)
+ {
+ case BPSTAT_WHAT_SET_LONGJMP_RESUME:
+ /* If we hit the breakpoint at longjmp, disable it for the
+ duration of this command. Then, install a temporary
+ breakpoint at the target of the jmp_buf. */
+ disable_longjmp_breakpoint();
+ remove_breakpoints ();
+ breakpoints_inserted = 0;
+ if (!GET_LONGJMP_TARGET(&jmp_buf_pc)) goto keep_going;
+
+ /* Need to blow away step-resume breakpoint, as it
+ interferes with us */
+ if (step_resume_breakpoint != NULL)
+ {
+ delete_breakpoint (step_resume_breakpoint);
+ step_resume_breakpoint = NULL;
+ what.step_resume = 0;
+ }
#if 0
- /* FIXME - Need to implement nested temporary breakpoints */
- if (step_over_calls > 0)
- set_longjmp_resume_breakpoint(jmp_buf_pc,
- get_current_frame());
- else
+ /* FIXME - Need to implement nested temporary breakpoints */
+ if (step_over_calls > 0)
+ set_longjmp_resume_breakpoint(jmp_buf_pc,
+ get_current_frame());
+ else
#endif /* 0 */
- set_longjmp_resume_breakpoint(jmp_buf_pc, NULL);
- handling_longjmp = 1; /* FIXME */
- goto keep_going;
-
- case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME:
- case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME_SINGLE:
- remove_breakpoints ();
- breakpoints_inserted = 0;
+ set_longjmp_resume_breakpoint(jmp_buf_pc, NULL);
+ handling_longjmp = 1; /* FIXME */
+ goto keep_going;
+
+ case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME:
+ case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME_SINGLE:
+ remove_breakpoints ();
+ breakpoints_inserted = 0;
#if 0
- /* FIXME - Need to implement nested temporary breakpoints */
- if (step_over_calls
- && (stop_frame_address
- INNER_THAN step_frame_address))
- {
- another_trap = 1;
- goto keep_going;
- }
+ /* FIXME - Need to implement nested temporary breakpoints */
+ if (step_over_calls
+ && (stop_frame_address
+ INNER_THAN step_frame_address))
+ {
+ another_trap = 1;
+ goto keep_going;
+ }
#endif /* 0 */
- disable_longjmp_breakpoint();
- handling_longjmp = 0; /* FIXME */
- if (what == BPSTAT_WHAT_CLEAR_LONGJMP_RESUME)
- break;
- /* else fallthrough */
-
- case BPSTAT_WHAT_SINGLE:
- if (breakpoints_inserted)
- remove_breakpoints ();
- remove_step_breakpoint ();
- breakpoints_inserted = 0;
- another_trap = 1;
- /* Still need to check other stuff, at least the case
- where we are stepping and step out of the right range. */
- break;
-
- case BPSTAT_WHAT_STOP_NOISY:
- stop_print_frame = 1;
- goto stop_stepping;
-
- case BPSTAT_WHAT_STOP_SILENT:
- stop_print_frame = 0;
- goto stop_stepping;
-
- case BPSTAT_WHAT_KEEP_CHECKING:
+ disable_longjmp_breakpoint();
+ handling_longjmp = 0; /* FIXME */
+ if (what.main_action == BPSTAT_WHAT_CLEAR_LONGJMP_RESUME)
break;
- }
+ /* else fallthrough */
+
+ case BPSTAT_WHAT_SINGLE:
+ if (breakpoints_inserted)
+ remove_breakpoints ();
+ breakpoints_inserted = 0;
+ another_trap = 1;
+ /* Still need to check other stuff, at least the case
+ where we are stepping and step out of the right range. */
+ break;
+
+ case BPSTAT_WHAT_STOP_NOISY:
+ stop_print_frame = 1;
+ /* We are about to nuke the step_resume_breakpoint via the
+ cleanup chain, so no need to worry about it here. */
+ goto stop_stepping;
- if (stop_step_resume_break)
+ case BPSTAT_WHAT_STOP_SILENT:
+ stop_print_frame = 0;
+ /* We are about to nuke the step_resume_breakpoint via the
+ cleanup chain, so no need to worry about it here. */
+ goto stop_stepping;
+
+ case BPSTAT_WHAT_KEEP_CHECKING:
+ break;
+ }
+
+ if (what.step_resume)
{
- /* But if we have hit the step-resumption breakpoint,
- remove it. It has done its job getting us here.
- The sp test is to make sure that we don't get hung
- up in recursive calls in functions without frame
- pointers. If the stack pointer isn't outside of
- where the breakpoint was set (within a routine to be
- stepped over), we're in the middle of a recursive
- call. Not true for reg window machines (sparc)
- because the must change frames to call things and
- the stack pointer doesn't have to change if it
- the bp was set in a routine without a frame (pc can
- be stored in some other window).
-
- The removal of the sp test is to allow calls to
- alloca. Nasty things were happening. Oh, well,
- gdb can only handle one level deep of lack of
- frame pointer. */
-
- /*
- Disable test for step_frame_address match so that we always stop even if the
- frames don't match. Reason: if we hit the step_resume_breakpoint, there is
- no way to temporarily disable it so that we can step past it. If we leave
- the breakpoint in, then we loop forever repeatedly hitting, but never
- getting past the breakpoint. This change keeps nexting over recursive
- function calls from hanging gdb.
- */
-#if 0
- if (* step_frame_address == 0
- || (step_frame_address == stop_frame_address))
-#endif
- {
- remove_step_breakpoint ();
- step_resume_break_address = 0;
+ delete_breakpoint (step_resume_breakpoint);
+ step_resume_breakpoint = NULL;
- /* If were waiting for a trap, hitting the step_resume_break
- doesn't count as getting it. */
- if (trap_expected)
- another_trap = 1;
- }
+ /* If were waiting for a trap, hitting the step_resume_break
+ doesn't count as getting it. */
+ if (trap_expected)
+ another_trap = 1;
}
- }
+ }
/* We come here if we hit a breakpoint but should not
stop for it. Possibly we also were stepping
@@ -882,8 +823,7 @@ wait_for_inferior ()
/* If this is the breakpoint at the end of a stack dummy,
just stop silently. */
- if (!random_signal
- && PC_IN_CALL_DUMMY (stop_pc, stop_sp, stop_frame_address))
+ if (PC_IN_CALL_DUMMY (stop_pc, stop_sp, stop_frame_address))
{
stop_print_frame = 0;
stop_stack_dummy = 1;
@@ -893,194 +833,241 @@ wait_for_inferior ()
break;
}
- if (step_resume_break_address)
+ if (step_resume_breakpoint)
/* Having a step-resume breakpoint overrides anything
else having to do with stepping commands until
that breakpoint is reached. */
- ;
+ /* I suspect this could/should be keep_going, because if the
+ check_sigtramp2 check succeeds, then it will put in another
+ step_resume_breakpoint, and we aren't (yet) prepared to nest
+ them. */
+ goto check_sigtramp2;
+
+ if (step_range_end == 0)
+ /* Likewise if we aren't even stepping. */
+ /* I'm not sure whether this needs to be check_sigtramp2 or
+ whether it could/should be keep_going. */
+ goto check_sigtramp2;
+
/* If stepping through a line, keep going if still within it. */
- else if (!random_signal
- && step_range_end
- && stop_pc >= step_range_start
- && stop_pc < step_range_end
- /* The step range might include the start of the
- function, so if we are at the start of the
- step range and either the stack or frame pointers
- just changed, we've stepped outside */
- && !(stop_pc == step_range_start
- && stop_frame_address
- && (stop_sp INNER_THAN prev_sp
- || stop_frame_address != step_frame_address)))
+ if (stop_pc >= step_range_start
+ && stop_pc < step_range_end
+ /* The step range might include the start of the
+ function, so if we are at the start of the
+ step range and either the stack or frame pointers
+ just changed, we've stepped outside */
+ && !(stop_pc == step_range_start
+ && stop_frame_address
+ && (stop_sp INNER_THAN prev_sp
+ || stop_frame_address != step_frame_address)))
{
- ;
+ /* We might be doing a BPSTAT_WHAT_SINGLE and getting a signal.
+ So definately need to check for sigtramp here. */
+ goto check_sigtramp2;
}
-
+
/* We stepped out of the stepping range. See if that was due
to a subroutine call that we should proceed to the end of. */
- else if (!random_signal && step_range_end)
+
+ /* Did we just take a signal? */
+ if (IN_SIGTRAMP (stop_pc, stop_func_name)
+ && !IN_SIGTRAMP (prev_pc, prev_func_name))
{
- /* Did we just take a signal? */
- if (IN_SIGTRAMP (stop_pc, stop_func_name)
- && !IN_SIGTRAMP (prev_pc, prev_func_name))
- {
- /* This code is needed at least in the following case:
- The user types "next" and then a signal arrives (before
- the "next" is done). */
- /* We've just taken a signal; go until we are back to
- the point where we took it and one more. */
- step_resume_break_address = prev_pc;
- step_resume_break_duplicate =
- breakpoint_here_p (step_resume_break_address);
- if (breakpoints_inserted)
- insert_step_breakpoint ();
- /* Make sure that the stepping range gets us past
- that instruction. */
- if (step_range_end == 1)
- step_range_end = (step_range_start = prev_pc) + 1;
- remove_breakpoints_on_following_step = 1;
- goto save_pc;
- }
+ /* This code is needed at least in the following case:
+ The user types "next" and then a signal arrives (before
+ the "next" is done). */
+ /* We've just taken a signal; go until we are back to
+ the point where we took it and one more. */
+ {
+ struct symtab_and_line sr_sal;
+
+ sr_sal.pc = prev_pc;
+ sr_sal.symtab = NULL;
+ sr_sal.line = 0;
+ step_resume_breakpoint =
+ set_momentary_breakpoint (sr_sal, get_current_frame (),
+ bp_step_resume);
+ if (breakpoints_inserted)
+ insert_breakpoints ();
+ }
- if (stop_func_start)
- {
- /* Do this after the IN_SIGTRAMP check; it might give
- an error. */
- prologue_pc = stop_func_start;
- SKIP_PROLOGUE (prologue_pc);
- }
+ /* If this is stepi or nexti, make sure that the stepping range
+ gets us past that instruction. */
+ if (step_range_end == 1)
+ /* FIXME: Does this run afoul of the code below which, if
+ we step into the middle of a line, resets the stepping
+ range? */
+ step_range_end = (step_range_start = prev_pc) + 1;
- /* ==> See comments at top of file on this algorithm. <==*/
-
- if ((stop_pc == stop_func_start
- || IN_SOLIB_TRAMPOLINE (stop_pc, stop_func_name))
- && (stop_func_start != prev_func_start
- || prologue_pc != stop_func_start
- || stop_sp != prev_sp))
- {
- /* It's a subroutine call.
- (0) If we are not stepping over any calls ("stepi"), we
- just stop.
- (1) If we're doing a "next", we want to continue through
- the call ("step over the call").
- (2) If we are in a function-call trampoline (a stub between
- the calling routine and the real function), locate
- the real function and change stop_func_start.
- (3) If we're doing a "step", and there are no debug symbols
- at the target of the call, we want to continue through
- it ("step over the call").
- (4) Otherwise, we want to stop soon, after the function
- prologue ("step into the call"). */
-
- if (step_over_calls == 0)
- {
- /* I presume that step_over_calls is only 0 when we're
- supposed to be stepping at the assembly language level. */
- stop_step = 1;
- break;
- }
+ remove_breakpoints_on_following_step = 1;
+ goto keep_going;
+ }
- if (step_over_calls > 0)
- goto step_over_function;
+ if (stop_func_start)
+ {
+ /* Do this after the IN_SIGTRAMP check; it might give
+ an error. */
+ prologue_pc = stop_func_start;
+ SKIP_PROLOGUE (prologue_pc);
+ }
- tmp = SKIP_TRAMPOLINE_CODE (stop_pc);
- if (tmp != 0)
- stop_func_start = tmp;
+ /* ==> See comments at top of file on this algorithm. <==*/
- /* If we have line number information for the function we
- are thinking of stepping into, step into it.
+ if ((stop_pc == stop_func_start
+ || IN_SOLIB_TRAMPOLINE (stop_pc, stop_func_name))
+ && (stop_func_start != prev_func_start
+ || prologue_pc != stop_func_start
+ || stop_sp != prev_sp))
+ {
+ /* It's a subroutine call. */
- If there are several symtabs at that PC (e.g. with include
- files), just want to know whether *any* of them have line
- numbers. find_pc_line handles this. */
- {
- struct symtab_and_line tmp_sal;
+ if (step_over_calls == 0)
+ {
+ /* I presume that step_over_calls is only 0 when we're
+ supposed to be stepping at the assembly language level
+ ("stepi"). Just stop. */
+ stop_step = 1;
+ break;
+ }
- tmp_sal = find_pc_line (stop_func_start, 0);
- if (tmp_sal.line != 0)
- goto step_into_function;
- }
+ if (step_over_calls > 0)
+ /* We're doing a "next". */
+ goto step_over_function;
+
+ /* If we are in a function call trampoline (a stub between
+ the calling routine and the real function), locate the real
+ function. That's what tells us (a) whether we want to step
+ into it at all, and (b) what prologue we want to run to
+ the end of, if we do step into it. */
+ tmp = SKIP_TRAMPOLINE_CODE (stop_pc);
+ if (tmp != 0)
+ stop_func_start = tmp;
+
+ /* If we have line number information for the function we
+ are thinking of stepping into, step into it.
+
+ If there are several symtabs at that PC (e.g. with include
+ files), just want to know whether *any* of them have line
+ numbers. find_pc_line handles this. */
+ {
+ struct symtab_and_line tmp_sal;
+
+ tmp_sal = find_pc_line (stop_func_start, 0);
+ if (tmp_sal.line != 0)
+ goto step_into_function;
+ }
step_over_function:
- /* A subroutine call has happened. */
- /* Set a special breakpoint after the return */
- step_resume_break_address =
- ADDR_BITS_REMOVE
- (SAVED_PC_AFTER_CALL (get_current_frame ()));
- step_resume_break_duplicate
- = breakpoint_here_p (step_resume_break_address);
- if (breakpoints_inserted)
- insert_step_breakpoint ();
- goto save_pc;
+ /* A subroutine call has happened. */
+ {
+ /* Set a special breakpoint after the return */
+ struct symtab_and_line sr_sal;
+ sr_sal.pc =
+ ADDR_BITS_REMOVE
+ (SAVED_PC_AFTER_CALL (get_current_frame ()));
+ sr_sal.symtab = NULL;
+ sr_sal.line = 0;
+ step_resume_breakpoint =
+ set_momentary_breakpoint (sr_sal, get_current_frame (),
+ bp_step_resume);
+ if (breakpoints_inserted)
+ insert_breakpoints ();
+ }
+ goto keep_going;
step_into_function:
- /* Subroutine call with source code we should not step over.
- Do step to the first line of code in it. */
- SKIP_PROLOGUE (stop_func_start);
- sal = find_pc_line (stop_func_start, 0);
- /* Use the step_resume_break to step until
- the end of the prologue, even if that involves jumps
- (as it seems to on the vax under 4.2). */
- /* If the prologue ends in the middle of a source line,
- continue to the end of that source line.
- Otherwise, just go to end of prologue. */
+ /* Subroutine call with source code we should not step over.
+ Do step to the first line of code in it. */
+ SKIP_PROLOGUE (stop_func_start);
+ sal = find_pc_line (stop_func_start, 0);
+ /* Use the step_resume_break to step until
+ the end of the prologue, even if that involves jumps
+ (as it seems to on the vax under 4.2). */
+ /* If the prologue ends in the middle of a source line,
+ continue to the end of that source line.
+ Otherwise, just go to end of prologue. */
#ifdef PROLOGUE_FIRSTLINE_OVERLAP
- /* no, don't either. It skips any code that's
- legitimately on the first line. */
+ /* no, don't either. It skips any code that's
+ legitimately on the first line. */
#else
- if (sal.end && sal.pc != stop_func_start)
- stop_func_start = sal.end;
+ if (sal.end && sal.pc != stop_func_start)
+ stop_func_start = sal.end;
#endif
- if (stop_func_start == stop_pc)
- {
- /* We are already there: stop now. */
- stop_step = 1;
- break;
- }
- else
- /* Put the step-breakpoint there and go until there. */
- {
- step_resume_break_address = stop_func_start;
-
- step_resume_break_duplicate
- = breakpoint_here_p (step_resume_break_address);
- if (breakpoints_inserted)
- insert_step_breakpoint ();
- /* Do not specify what the fp should be when we stop
- since on some machines the prologue
- is where the new fp value is established. */
- step_frame_address = 0;
- /* And make sure stepping stops right away then. */
- step_range_end = step_range_start;
- }
- goto save_pc;
+ if (stop_func_start == stop_pc)
+ {
+ /* We are already there: stop now. */
+ stop_step = 1;
+ break;
+ }
+ else
+ /* Put the step-breakpoint there and go until there. */
+ {
+ struct symtab_and_line sr_sal;
+
+ sr_sal.pc = stop_func_start;
+ sr_sal.symtab = NULL;
+ sr_sal.line = 0;
+ /* Do not specify what the fp should be when we stop
+ since on some machines the prologue
+ is where the new fp value is established. */
+ step_resume_breakpoint =
+ set_momentary_breakpoint (sr_sal, (CORE_ADDR)0,
+ bp_step_resume);
+ if (breakpoints_inserted)
+ insert_breakpoints ();
+
+ /* And make sure stepping stops right away then. */
+ step_range_end = step_range_start;
}
+ goto keep_going;
+ }
- /* We've wandered out of the step range (but haven't done a
- subroutine call or return). */
+ /* We've wandered out of the step range (but haven't done a
+ subroutine call or return). (Is that true? I think we get
+ here if we did a return and maybe a longjmp). */
- sal = find_pc_line(stop_pc, 0);
-
- if (step_range_end == 1 || /* stepi or nexti */
- sal.line == 0 || /* ...or no line # info */
- (stop_pc == sal.pc /* ...or we're at the start */
- && current_line != sal.line)) { /* of a different line */
- /* Stop because we're done stepping. */
- stop_step = 1;
- break;
- } else {
- /* We aren't done stepping, and we have line number info for $pc.
- Optimize by setting the step_range for the line.
- (We might not be in the original line, but if we entered a
- new line in mid-statement, we continue stepping. This makes
- things like for(;;) statements work better.) */
- step_range_start = sal.pc;
- step_range_end = sal.end;
- goto save_pc;
- }
- /* We never fall through here */
+ sal = find_pc_line(stop_pc, 0);
+
+ if (step_range_end == 1)
+ {
+ /* It is stepi or nexti. We always want to stop stepping after
+ one instruction. */
+ stop_step = 1;
+ break;
+ }
+
+ if (sal.line == 0)
+ {
+ /* We have no line number information. That means to stop
+ stepping (does this always happen right after one instruction,
+ when we do "s" in a function with no line numbers,
+ or can this happen as a result of a return or longjmp?). */
+ stop_step = 1;
+ break;
+ }
+
+ if (stop_pc == sal.pc && current_line != sal.line)
+ {
+ /* We are at the start of a different line. So stop. Note that
+ we don't stop if we step into the middle of a different line.
+ That is said to make things like for (;;) statements work
+ better. */
+ stop_step = 1;
+ break;
}
+ /* We aren't done stepping.
+
+ Optimize by setting the stepping range to the line.
+ (We might not be in the original line, but if we entered a
+ new line in mid-statement, we continue stepping. This makes
+ things like for(;;) statements work better.) */
+ step_range_start = sal.pc;
+ step_range_end = sal.end;
+ goto keep_going;
+
+ check_sigtramp2:
if (trap_expected
&& IN_SIGTRAMP (stop_pc, stop_func_name)
&& !IN_SIGTRAMP (prev_pc, prev_func_name))
@@ -1090,27 +1077,31 @@ step_into_function:
us stop), thus stepping into sigtramp.
So we need to set a step_resume_break_address breakpoint
- and continue until we hit it, and then step. */
- step_resume_break_address = prev_pc;
- /* Always 1, I think, but it's probably easier to have
- the step_resume_break as usual rather than trying to
- re-use the breakpoint which is already there. */
- step_resume_break_duplicate =
- breakpoint_here_p (step_resume_break_address);
+ and continue until we hit it, and then step. FIXME: This should
+ be more enduring than a step_resume breakpoint; we should know
+ that we will later need to keep going rather than re-hitting
+ the breakpoint here (see testsuite/gdb.t06/signals.exp where
+ it says "exceedingly difficult"). */
+ struct symtab_and_line sr_sal;
+
+ sr_sal.pc = prev_pc;
+ sr_sal.symtab = NULL;
+ sr_sal.line = 0;
+ step_resume_breakpoint =
+ set_momentary_breakpoint (sr_sal, get_current_frame (),
+ bp_step_resume);
if (breakpoints_inserted)
- insert_step_breakpoint ();
+ insert_breakpoints ();
+
remove_breakpoints_on_following_step = 1;
another_trap = 1;
}
-/* My apologies to the gods of structured programming. */
-/* Come to this label when you need to resume the inferior. It's really much
- cleaner at this time to do a goto than to try and figure out what the
- if-else chain ought to look like!! */
-
keep_going:
+ /* Come to this label when you need to resume the inferior.
+ It's really much cleaner to do a goto than a maze of if-else
+ conditions. */
-save_pc:
/* Save the pc before execution, to compare with pc after stop. */
prev_pc = read_pc (); /* Might have been DECR_AFTER_BREAK */
prev_func_start = stop_func_start; /* Ok, since if DECR_PC_AFTER
@@ -1129,8 +1120,8 @@ save_pc:
/* We took a signal (which we are supposed to pass through to
the inferior, else we'd have done a break above) and we
haven't yet gotten our trap. Simply continue. */
- resume ((step_range_end && !step_resume_break_address)
- || (trap_expected && !step_resume_break_address)
+ resume ((step_range_end && step_resume_breakpoint == NULL)
+ || (trap_expected && step_resume_breakpoint == NULL)
|| bpstat_should_step (),
stop_signal);
}
@@ -1149,7 +1140,7 @@ save_pc:
to one-proceed past a breakpoint. */
/* If we've just finished a special step resume and we don't
want to hit a breakpoint, pull em out. */
- if (!step_resume_break_address &&
+ if (step_resume_breakpoint == NULL &&
remove_breakpoints_on_following_step)
{
remove_breakpoints_on_following_step = 0;
@@ -1157,9 +1148,8 @@ save_pc:
breakpoints_inserted = 0;
}
else if (!breakpoints_inserted &&
- (step_resume_break_address != 0 || !another_trap))
+ (step_resume_breakpoint != NULL || !another_trap))
{
- insert_step_breakpoint ();
breakpoints_failed = insert_breakpoints ();
if (breakpoints_failed)
break;
@@ -1190,7 +1180,7 @@ save_pc:
}
#endif /* SHIFT_INST_REGS */
- resume ((!step_resume_break_address
+ resume ((step_resume_breakpoint == NULL
&& !handling_longjmp
&& (step_range_end
|| trap_expected))
@@ -1210,6 +1200,7 @@ save_pc:
prev_func_name = stop_func_name;
prev_sp = stop_sp;
}
+ do_cleanups (old_cleanups);
}
/* Here to return control to GDB when the inferior stops for real.
@@ -1237,9 +1228,6 @@ normal_stop ()
The same program may be running in another process.\n");
}
- if (target_has_execution)
- remove_step_breakpoint ();
-
if (target_has_execution && breakpoints_inserted)
if (remove_breakpoints ())
{
@@ -1325,23 +1313,6 @@ hook_stop_stub (cmd)
execute_user_command ((struct cmd_list_element *)cmd, 0);
return (0);
}
-
-
-static void
-insert_step_breakpoint ()
-{
- if (step_resume_break_address && !step_resume_break_duplicate)
- target_insert_breakpoint (step_resume_break_address,
- step_resume_break_shadow);
-}
-
-static void
-remove_step_breakpoint ()
-{
- if (step_resume_break_address && !step_resume_break_duplicate)
- target_remove_breakpoint (step_resume_break_address,
- step_resume_break_shadow);
-}
int signal_stop_state (signo)
int signo;
@@ -1612,7 +1583,6 @@ save_inferior_status (inf_status, restore_stack_info)
inf_status->step_range_end = step_range_end;
inf_status->step_frame_address = step_frame_address;
inf_status->step_over_calls = step_over_calls;
- inf_status->step_resume_break_address = step_resume_break_address;
inf_status->stop_after_trap = stop_after_trap;
inf_status->stop_soon_quietly = stop_soon_quietly;
/* Save original bpstat chain here; replace it with copy of chain.
@@ -1650,7 +1620,6 @@ restore_inferior_status (inf_status)
step_range_end = inf_status->step_range_end;
step_frame_address = inf_status->step_frame_address;
step_over_calls = inf_status->step_over_calls;
- step_resume_break_address = inf_status->step_resume_break_address;
stop_after_trap = inf_status->stop_after_trap;
stop_soon_quietly = inf_status->stop_soon_quietly;
bpstat_clear (&stop_bpstat);