process.
Copyright 1986, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994,
- 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002 Free Software
- Foundation, Inc.
+ 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004 Free
+ Software Foundation, Inc.
This file is part of GDB.
#include "inf-loop.h"
#include "regcache.h"
#include "value.h"
+#include "observer.h"
+#include "language.h"
+#include "gdb_assert.h"
/* Prototypes for local functions */
static int hook_stop_stub (void *);
-static void delete_breakpoint_current_contents (void *);
-
-static void set_follow_fork_mode_command (char *arg, int from_tty,
- struct cmd_list_element *c);
-
static int restore_selected_frame (void *);
static void build_infrun (void);
-static int follow_fork ();
+static int follow_fork (void);
static void set_schedlock_func (char *args, int from_tty,
struct cmd_list_element *c);
static void xdb_handle_command (char *args, int from_tty);
+static int prepare_to_proceed (void);
+
void _initialize_infrun (void);
int inferior_ignoring_startup_exec_events = 0;
static int may_follow_exec = MAY_FOLLOW_EXEC;
-/* Dynamic function trampolines are similar to solib trampolines in that they
- are between the caller and the callee. The difference is that when you
- enter a dynamic trampoline, you can't determine the callee's address. Some
- (usually complex) code needs to run in the dynamic trampoline to figure out
- the callee's address. This macro is usually called twice. First, when we
- enter the trampoline (looks like a normal function call at that point). It
- should return the PC of a point within the trampoline where the callee's
- address is known. Second, when we hit the breakpoint, this routine returns
- the callee's address. At that point, things proceed as per a step resume
- breakpoint. */
-
-#ifndef DYNAMIC_TRAMPOLINE_NEXTPC
-#define DYNAMIC_TRAMPOLINE_NEXTPC(pc) 0
-#endif
-
/* If the program uses ELF-style shared libraries, then calls to
functions in shared libraries go through stubs, which live in a
table called the PLT (Procedure Linkage Table). The first time the
#define IN_SOLIB_DYNSYM_RESOLVE_CODE(pc) 0
#endif
-#ifndef SKIP_SOLIB_RESOLVER
-#define SKIP_SOLIB_RESOLVER(pc) 0
-#endif
-
/* This function returns TRUE if pc is the address of an instruction
that lies within the dynamic linker (such as the event hook, or the
dld itself).
#define SOLIB_IN_DYNAMIC_LINKER(pid,pc) 0
#endif
-/* On MIPS16, a function that returns a floating point value may call
- a library helper function to copy the return value to a floating point
- register. The IGNORE_HELPER_CALL macro returns non-zero if we
- should ignore (i.e. step over) this function call. */
-#ifndef IGNORE_HELPER_CALL
-#define IGNORE_HELPER_CALL(pc) 0
-#endif
-
/* On some systems, the PC may be left pointing at an instruction that won't
actually be executed. This is usually indicated by a bit in the PSW. If
we find ourselves in such a state, then we step the target beyond the
#define HAVE_STEPPABLE_WATCHPOINT 1
#endif
-#ifndef HAVE_CONTINUABLE_WATCHPOINT
-#define HAVE_CONTINUABLE_WATCHPOINT 0
-#else
-#undef HAVE_CONTINUABLE_WATCHPOINT
-#define HAVE_CONTINUABLE_WATCHPOINT 1
-#endif
-
#ifndef CANNOT_STEP_HW_WATCHPOINTS
#define CANNOT_STEP_HW_WATCHPOINTS 0
#else
static int stop_on_solib_events;
#endif
-#ifdef HP_OS_BUG
-/* Nonzero if the next time we try to continue the inferior, it will
- step one instruction and generate a spurious trace trap.
- This is used to compensate for a bug in HP-UX. */
-
-static int trap_expected_after_continue;
-#endif
-
/* Nonzero means expecting a trace trap
and should stop the inferior and return silently when it happens. */
when running in the shell before the child program has been exec'd;
and when running some kinds of remote stuff (FIXME?). */
-int stop_soon_quietly;
+enum stop_kind stop_soon;
/* Nonzero if proceed is being used for a "finish" command or a similar
situation when stop_registers should be saved. */
static int stop_print_frame;
static struct breakpoint *step_resume_breakpoint = NULL;
-static struct breakpoint *through_sigtramp_breakpoint = NULL;
/* On some platforms (e.g., HP-UX), hardware watchpoints have bad
interactions with an inferior that is running a kernel function
static int number_of_threads_in_syscalls;
/* This is a cached copy of the pid/waitstatus of the last event
- returned by target_wait()/target_wait_hook(). This information is
- returned by get_last_target_status(). */
+ returned by target_wait()/deprecated_target_wait_hook(). This
+ information is returned by get_last_target_status(). */
static ptid_t target_last_wait_ptid;
static struct target_waitstatus target_last_waitstatus;
struct
{
int parent_pid;
- int saw_parent_fork;
int child_pid;
- int saw_child_fork;
- int saw_child_exec;
}
fork_event;
char *execd_pathname;
}
pending_follow;
-static const char follow_fork_mode_ask[] = "ask";
static const char follow_fork_mode_child[] = "child";
static const char follow_fork_mode_parent[] = "parent";
static const char *follow_fork_mode_kind_names[] = {
- follow_fork_mode_ask,
follow_fork_mode_child,
follow_fork_mode_parent,
NULL
\f
static int
-follow_fork ()
+follow_fork (void)
{
- const char *follow_mode = follow_fork_mode_string;
- int follow_child = (follow_mode == follow_fork_mode_child);
-
- /* Or, did the user not know, and want us to ask? */
- if (follow_fork_mode_string == follow_fork_mode_ask)
- {
- internal_error (__FILE__, __LINE__,
- "follow_inferior_fork: \"ask\" mode not implemented");
- /* follow_mode = follow_fork_mode_...; */
- }
-
- pending_follow.fork_event.saw_parent_fork = 0;
- pending_follow.fork_event.saw_child_fork = 0;
+ int follow_child = (follow_fork_mode_string == follow_fork_mode_child);
return target_follow_fork (follow_child);
}
step_range_start = 0;
step_range_end = 0;
- /* If there was one, it's gone now. */
- through_sigtramp_breakpoint = NULL;
-
/* What is this a.out's name? */
printf_unfiltered ("Executing new program: %s\n", execd_pathname);
because we cannot remove the breakpoints in the inferior process
until after the `wait' in `wait_for_inferior'. */
static int singlestep_breakpoints_inserted_p = 0;
+
+/* The thread we inserted single-step breakpoints for. */
+static ptid_t singlestep_ptid;
+
+/* If another thread hit the singlestep breakpoint, we save the original
+ thread here so that we can resume single-stepping it later. */
+static ptid_t saved_singlestep_ptid;
+static int stepping_past_singlestep_breakpoint;
\f
/* Things to clean up if we QUIT out of resume (). */
-/* ARGSUSED */
static void
resume_cleanups (void *ignore)
{
static void
set_schedlock_func (char *args, int from_tty, struct cmd_list_element *c)
{
- /* NOTE: cagney/2002-03-17: The add_show_from_set() function clones
- the set command passed as a parameter. The clone operation will
- include (BUG?) any ``set'' command callback, if present.
- Commands like ``info set'' call all the ``show'' command
- callbacks. Unfortunatly, for ``show'' commands cloned from
- ``set'', this includes callbacks belonging to ``set'' commands.
- Making this worse, this only occures if add_show_from_set() is
- called after add_cmd_sfunc() (BUG?). */
+ /* NOTE: cagney/2002-03-17: The deprecated_add_show_from_set()
+ function clones the set command passed as a parameter. The clone
+ operation will include (BUG?) any ``set'' command callback, if
+ present. Commands like ``info set'' call all the ``show''
+ command callbacks. Unfortunately, for ``show'' commands cloned
+ from ``set'', this includes callbacks belonging to ``set''
+ commands. Making this worse, this only occures if
+ deprecated_add_show_from_set() is called after add_cmd_sfunc()
+ (BUG?). */
if (cmd_type (c) == set_cmd)
if (!target_can_lock_scheduler)
{
/* and do not pull these breakpoints until after a `wait' in
`wait_for_inferior' */
singlestep_breakpoints_inserted_p = 1;
+ singlestep_ptid = inferior_ptid;
}
- /* Handle any optimized stores to the inferior NOW... */
-#ifdef DO_DEFERRED_STORES
- DO_DEFERRED_STORES;
-#endif
-
/* If there were any forks/vforks/execs that were caught and are
now to be followed, then do so. */
switch (pending_follow.kind)
resume_ptid = RESUME_ALL; /* Default */
- if ((step || singlestep_breakpoints_inserted_p) &&
- !breakpoints_inserted && breakpoint_here_p (read_pc ()))
+ if ((step || singlestep_breakpoints_inserted_p)
+ && (stepping_past_singlestep_breakpoint
+ || (!breakpoints_inserted && breakpoint_here_p (read_pc ()))))
{
/* Stepping past a breakpoint without inserting breakpoints.
Make sure only the current thread gets to step, so that
resume_ptid = inferior_ptid;
}
- if ((scheduler_mode == schedlock_on) ||
- (scheduler_mode == schedlock_step &&
- (step || singlestep_breakpoints_inserted_p)))
+ if ((scheduler_mode == schedlock_on)
+ || (scheduler_mode == schedlock_step
+ && (step || singlestep_breakpoints_inserted_p)))
{
/* User-settable 'scheduler' mode requires solo thread resume. */
resume_ptid = inferior_ptid;
step_frame_id = null_frame_id;
step_over_calls = STEP_OVER_UNDEBUGGABLE;
stop_after_trap = 0;
- stop_soon_quietly = 0;
+ stop_soon = NO_STOP_QUIETLY;
proceed_to_finish = 0;
breakpoint_proceeded = 1; /* We're about to proceed... */
bpstat_clear (&stop_bpstat);
}
+/* This should be suitable for any targets that support threads. */
+
+static int
+prepare_to_proceed (void)
+{
+ ptid_t wait_ptid;
+ struct target_waitstatus wait_status;
+
+ /* Get the last target status returned by target_wait(). */
+ get_last_target_status (&wait_ptid, &wait_status);
+
+ /* Make sure we were stopped either at a breakpoint, or because
+ of a Ctrl-C. */
+ if (wait_status.kind != TARGET_WAITKIND_STOPPED
+ || (wait_status.value.sig != TARGET_SIGNAL_TRAP
+ && wait_status.value.sig != TARGET_SIGNAL_INT))
+ {
+ return 0;
+ }
+
+ if (!ptid_equal (wait_ptid, minus_one_ptid)
+ && !ptid_equal (inferior_ptid, wait_ptid))
+ {
+ /* Switched over from WAIT_PID. */
+ CORE_ADDR wait_pc = read_pc_pid (wait_ptid);
+
+ if (wait_pc != read_pc ())
+ {
+ /* Switch back to WAIT_PID thread. */
+ inferior_ptid = wait_ptid;
+
+ /* FIXME: This stuff came from switch_to_thread() in
+ thread.c (which should probably be a public function). */
+ flush_cached_frames ();
+ registers_changed ();
+ stop_pc = wait_pc;
+ select_frame (get_current_frame ());
+ }
+
+ /* We return 1 to indicate that there is a breakpoint here,
+ so we need to step over it before continuing to avoid
+ hitting it straight away. */
+ if (breakpoint_here_p (wait_pc))
+ return 1;
+ }
+
+ return 0;
+
+}
+
+/* Record the pc of the program the last time it stopped. This is
+ just used internally by wait_for_inferior, but need to be preserved
+ over calls to it and cleared when the inferior is started. */
+static CORE_ADDR prev_pc;
+
/* Basic routine for continuing the program in various fashions.
ADDR is the address to resume at, or -1 for resume where stopped.
write_pc (addr);
}
-#ifdef PREPARE_TO_PROCEED
/* In a multi-threaded task we may select another thread
and then continue or step.
any execution (i.e. it will report a breakpoint hit
incorrectly). So we must step over it first.
- PREPARE_TO_PROCEED checks the current thread against the thread
+ prepare_to_proceed checks the current thread against the thread
that reported the most recent event. If a step-over is required
it returns TRUE and sets the current thread to the old thread. */
- if (PREPARE_TO_PROCEED (1) && breakpoint_here_p (read_pc ()))
- {
- oneproc = 1;
- }
-
-#endif /* PREPARE_TO_PROCEED */
-
-#ifdef HP_OS_BUG
- if (trap_expected_after_continue)
- {
- /* If (step == 0), a trap will be automatically generated after
- the first instruction is executed. Force step one
- instruction to clear this condition. This should not occur
- if step is nonzero, but it is harmless in that case. */
- oneproc = 1;
- trap_expected_after_continue = 0;
- }
-#endif /* HP_OS_BUG */
+ if (prepare_to_proceed () && breakpoint_here_p (read_pc ()))
+ oneproc = 1;
if (oneproc)
/* We will get a trace trap after one instruction.
{
insert_breakpoints ();
/* If we get here there was no call to error() in
- insert breakpoints -- so they were inserted. */
+ insert breakpoints -- so they were inserted. */
breakpoints_inserted = 1;
}
inferior. */
gdb_flush (gdb_stdout);
+ /* Refresh prev_pc value just prior to resuming. This used to be
+ done in stop_stepping, however, setting prev_pc there did not handle
+ scenarios such as inferior function calls or returning from
+ a function via the return command. In those cases, the prev_pc
+ value was not set properly for subsequent commands. The prev_pc value
+ is used to initialize the starting line number in the ecs. With an
+ invalid value, the gdb next command ends up stopping at the position
+ represented by the next line table entry past our start position.
+ On platforms that generate one line table entry per line, this
+ is not a problem. However, on the ia64, the compiler generates
+ extraneous line table entries that do not increase the line number.
+ When we issue the gdb next command on the ia64 after an inferior call
+ or a return command, we often end up a few instructions forward, still
+ within the original line we started.
+
+ An attempt was made to have init_execution_control_state () refresh
+ the prev_pc value before calculating the line number. This approach
+ did not work because on platforms that use ptrace, the pc register
+ cannot be read unless the inferior is stopped. At that point, we
+ are not guaranteed the inferior is stopped and so the read_pc ()
+ call can fail. Setting the prev_pc value here ensures the value is
+ updated correctly when the inferior is stopped. */
+ prev_pc = read_pc ();
+
/* Resume inferior. */
resume (oneproc || step || bpstat_should_step (), stop_signal);
and in any case decode why it stopped, and act accordingly. */
/* Do this only if we are not using the event loop, or if the target
does not support asynchronous execution. */
- if (!event_loop_p || !target_can_async_p ())
+ if (!target_can_async_p ())
{
wait_for_inferior ();
normal_stop ();
}
}
-
-/* Record the pc and sp of the program the last time it stopped.
- These are just used internally by wait_for_inferior, but need
- to be preserved over calls to it and cleared when the inferior
- is started. */
-static CORE_ADDR prev_pc;
-static CORE_ADDR prev_func_start;
-static char *prev_func_name;
\f
/* Start remote-debugging of a machine over a serial link. */
{
init_thread_list ();
init_wait_for_inferior ();
- stop_soon_quietly = 1;
+ stop_soon = STOP_QUIETLY;
trap_expected = 0;
/* Always go on waiting for the target, regardless of the mode. */
{
/* These are meaningless until the first time through wait_for_inferior. */
prev_pc = 0;
- prev_func_start = 0;
- prev_func_name = NULL;
-#ifdef HP_OS_BUG
- trap_expected_after_continue = 0;
-#endif
breakpoints_inserted = 0;
breakpoint_init_inferior (inf_starting);
/* The first resume is not following a fork/vfork/exec. */
pending_follow.kind = TARGET_WAITKIND_SPURIOUS; /* I.e., none. */
- pending_follow.fork_event.saw_parent_fork = 0;
- pending_follow.fork_event.saw_child_fork = 0;
- pending_follow.fork_event.saw_child_exec = 0;
/* See wait_for_inferior's handling of SYSCALL_ENTRY/RETURN events. */
number_of_threads_in_syscalls = 0;
clear_proceed_status ();
-}
-static void
-delete_breakpoint_current_contents (void *arg)
-{
- struct breakpoint **breakpointp = (struct breakpoint **) arg;
- if (*breakpointp != NULL)
- {
- delete_breakpoint (*breakpointp);
- *breakpointp = NULL;
- }
+ stepping_past_singlestep_breakpoint = 0;
}
\f
/* This enum encodes possible reasons for doing a target_wait, so that
CORE_ADDR stop_func_end;
char *stop_func_name;
struct symtab_and_line sal;
- int remove_breakpoints_on_following_step;
int current_line;
struct symtab *current_symtab;
int handling_longjmp; /* FIXME */
ptid_t ptid;
ptid_t saved_inferior_ptid;
- int update_step_sp;
+ int step_after_step_resume_breakpoint;
int stepping_through_solib_after_catch;
bpstat stepping_through_solib_catchpoints;
int enable_hw_watchpoints_after_wait;
- int stepping_through_sigtramp;
int new_thread_event;
struct target_waitstatus tmpstatus;
enum infwait_states infwait_state;
void handle_inferior_event (struct execution_control_state *ecs);
-static void check_sigtramp2 (struct execution_control_state *ecs);
static void step_into_function (struct execution_control_state *ecs);
-static void step_over_function (struct execution_control_state *ecs);
+static void insert_step_resume_breakpoint_at_frame (struct frame_info *step_frame);
+static void insert_step_resume_breakpoint_at_sal (struct symtab_and_line sr_sal,
+ struct frame_id sr_id);
static void stop_stepping (struct execution_control_state *ecs);
static void prepare_to_wait (struct execution_control_state *ecs);
static void keep_going (struct execution_control_state *ecs);
old_cleanups = make_cleanup (delete_step_resume_breakpoint,
&step_resume_breakpoint);
- make_cleanup (delete_breakpoint_current_contents,
- &through_sigtramp_breakpoint);
/* wfi still stays in a loop, so it's OK just to take the address of
a local to get the ecs pointer. */
while (1)
{
- if (target_wait_hook)
- ecs->ptid = target_wait_hook (ecs->waiton_ptid, ecs->wp);
+ if (deprecated_target_wait_hook)
+ ecs->ptid = deprecated_target_wait_hook (ecs->waiton_ptid, ecs->wp);
else
ecs->ptid = target_wait (ecs->waiton_ptid, ecs->wp);
{
old_cleanups = make_exec_cleanup (delete_step_resume_breakpoint,
&step_resume_breakpoint);
- make_exec_cleanup (delete_breakpoint_current_contents,
- &through_sigtramp_breakpoint);
/* Fill in with reasonable starting values. */
init_execution_control_state (async_ecs);
registers_changed ();
}
- if (target_wait_hook)
+ if (deprecated_target_wait_hook)
async_ecs->ptid =
- target_wait_hook (async_ecs->waiton_ptid, async_ecs->wp);
+ deprecated_target_wait_hook (async_ecs->waiton_ptid, async_ecs->wp);
else
async_ecs->ptid = target_wait (async_ecs->waiton_ptid, async_ecs->wp);
{
/* ecs->another_trap? */
ecs->random_signal = 0;
- ecs->remove_breakpoints_on_following_step = 0;
+ ecs->step_after_step_resume_breakpoint = 0;
ecs->handling_longjmp = 0; /* FIXME */
- ecs->update_step_sp = 0;
ecs->stepping_through_solib_after_catch = 0;
ecs->stepping_through_solib_catchpoints = NULL;
ecs->enable_hw_watchpoints_after_wait = 0;
- ecs->stepping_through_sigtramp = 0;
ecs->sal = find_pc_line (prev_pc, 0);
ecs->current_line = ecs->sal.line;
ecs->current_symtab = ecs->sal.symtab;
ecs->wp = &(ecs->ws);
}
-/* Call this function before setting step_resume_breakpoint, as a
- sanity check. There should never be more than one step-resume
- breakpoint per thread, so we should never be setting a new
- step_resume_breakpoint when one is already active. */
-static void
-check_for_old_step_resume_breakpoint (void)
-{
- if (step_resume_breakpoint)
- warning
- ("GDB bug: infrun.c (wait_for_inferior): dropping old step_resume breakpoint");
-}
-
/* Return the cached copy of the last pid/waitstatus returned by
- target_wait()/target_wait_hook(). The data is actually cached by
- handle_inferior_event(), which gets called immediately after
- target_wait()/target_wait_hook(). */
+ target_wait()/deprecated_target_wait_hook(). The data is actually
+ cached by handle_inferior_event(), which gets called immediately
+ after target_wait()/deprecated_target_wait_hook(). */
void
get_last_target_status (ptid_t *ptidp, struct target_waitstatus *status)
{ /* Perform infrun state context switch: */
/* Save infrun state for the old thread. */
save_infrun_state (inferior_ptid, prev_pc,
- prev_func_start, prev_func_name,
trap_expected, step_resume_breakpoint,
- through_sigtramp_breakpoint, step_range_start,
+ step_range_start,
step_range_end, &step_frame_id,
ecs->handling_longjmp, ecs->another_trap,
ecs->stepping_through_solib_after_catch,
ecs->stepping_through_solib_catchpoints,
- ecs->stepping_through_sigtramp,
- ecs->current_line, ecs->current_symtab, step_sp);
+ ecs->current_line, ecs->current_symtab);
/* Load infrun state for the new thread. */
load_infrun_state (ecs->ptid, &prev_pc,
- &prev_func_start, &prev_func_name,
&trap_expected, &step_resume_breakpoint,
- &through_sigtramp_breakpoint, &step_range_start,
+ &step_range_start,
&step_range_end, &step_frame_id,
&ecs->handling_longjmp, &ecs->another_trap,
&ecs->stepping_through_solib_after_catch,
&ecs->stepping_through_solib_catchpoints,
- &ecs->stepping_through_sigtramp,
- &ecs->current_line, &ecs->current_symtab, &step_sp);
+ &ecs->current_line, &ecs->current_symtab);
}
inferior_ptid = ecs->ptid;
}
+static void
+adjust_pc_after_break (struct execution_control_state *ecs)
+{
+ CORE_ADDR breakpoint_pc;
+
+ /* If this target does not decrement the PC after breakpoints, then
+ we have nothing to do. */
+ if (DECR_PC_AFTER_BREAK == 0)
+ return;
+
+ /* If we've hit a breakpoint, we'll normally be stopped with SIGTRAP. If
+ we aren't, just return.
+
+ We assume that waitkinds other than TARGET_WAITKIND_STOPPED are not
+ affected by DECR_PC_AFTER_BREAK. Other waitkinds which are implemented
+ by software breakpoints should be handled through the normal breakpoint
+ layer.
+
+ NOTE drow/2004-01-31: On some targets, breakpoints may generate
+ different signals (SIGILL or SIGEMT for instance), but it is less
+ clear where the PC is pointing afterwards. It may not match
+ DECR_PC_AFTER_BREAK. I don't know any specific target that generates
+ these signals at breakpoints (the code has been in GDB since at least
+ 1992) so I can not guess how to handle them here.
+
+ In earlier versions of GDB, a target with HAVE_NONSTEPPABLE_WATCHPOINTS
+ would have the PC after hitting a watchpoint affected by
+ DECR_PC_AFTER_BREAK. I haven't found any target with both of these set
+ in GDB history, and it seems unlikely to be correct, so
+ HAVE_NONSTEPPABLE_WATCHPOINTS is not checked here. */
+
+ if (ecs->ws.kind != TARGET_WAITKIND_STOPPED)
+ return;
+
+ if (ecs->ws.value.sig != TARGET_SIGNAL_TRAP)
+ return;
+
+ /* Find the location where (if we've hit a breakpoint) the
+ breakpoint would be. */
+ breakpoint_pc = read_pc_pid (ecs->ptid) - DECR_PC_AFTER_BREAK;
+
+ if (SOFTWARE_SINGLE_STEP_P ())
+ {
+ /* When using software single-step, a SIGTRAP can only indicate
+ an inserted breakpoint. This actually makes things
+ easier. */
+ if (singlestep_breakpoints_inserted_p)
+ /* When software single stepping, the instruction at [prev_pc]
+ is never a breakpoint, but the instruction following
+ [prev_pc] (in program execution order) always is. Assume
+ that following instruction was reached and hence a software
+ breakpoint was hit. */
+ write_pc_pid (breakpoint_pc, ecs->ptid);
+ else if (software_breakpoint_inserted_here_p (breakpoint_pc))
+ /* The inferior was free running (i.e., no single-step
+ breakpoints inserted) and it hit a software breakpoint. */
+ write_pc_pid (breakpoint_pc, ecs->ptid);
+ }
+ else
+ {
+ /* When using hardware single-step, a SIGTRAP is reported for
+ both a completed single-step and a software breakpoint. Need
+ to differentiate between the two as the latter needs
+ adjusting but the former does not. */
+ if (currently_stepping (ecs))
+ {
+ if (prev_pc == breakpoint_pc
+ && software_breakpoint_inserted_here_p (breakpoint_pc))
+ /* Hardware single-stepped a software breakpoint (as
+ occures when the inferior is resumed with PC pointing
+ at not-yet-hit software breakpoint). Since the
+ breakpoint really is executed, the inferior needs to be
+ backed up to the breakpoint address. */
+ write_pc_pid (breakpoint_pc, ecs->ptid);
+ }
+ else
+ {
+ if (software_breakpoint_inserted_here_p (breakpoint_pc))
+ /* The inferior was free running (i.e., no hardware
+ single-step and no possibility of a false SIGTRAP) and
+ hit a software breakpoint. */
+ write_pc_pid (breakpoint_pc, ecs->ptid);
+ }
+ }
+}
/* Given an execution control state that has been freshly filled in
by an event from the inferior, figure out what it means and take
appropriate action. */
+int stepped_after_stopped_by_watchpoint;
+
void
handle_inferior_event (struct execution_control_state *ecs)
{
- CORE_ADDR tmp;
- int stepped_after_stopped_by_watchpoint;
+ /* NOTE: cagney/2003-03-28: If you're looking at this code and
+ thinking that the variable stepped_after_stopped_by_watchpoint
+ isn't used, then you're wrong! The macro STOPPED_BY_WATCHPOINT,
+ defined in the file "config/pa/nm-hppah.h", accesses the variable
+ indirectly. Mutter something rude about the HP merge. */
int sw_single_step_trap_p = 0;
+ int stopped_by_watchpoint = -1; /* Mark as unknown. */
/* Cache the last pid/waitstatus. */
target_last_wait_ptid = ecs->ptid;
target_last_waitstatus = *ecs->wp;
+ adjust_pc_after_break (ecs);
+
switch (ecs->infwait_state)
{
case infwait_thread_hop_state:
/* Cancel the waiton_ptid. */
ecs->waiton_ptid = pid_to_ptid (-1);
- /* Fall thru to the normal_state case. */
+ /* See comments where a TARGET_WAITKIND_SYSCALL_RETURN event
+ is serviced in this loop, below. */
+ if (ecs->enable_hw_watchpoints_after_wait)
+ {
+ TARGET_ENABLE_HW_WATCHPOINTS (PIDGET (inferior_ptid));
+ ecs->enable_hw_watchpoints_after_wait = 0;
+ }
+ stepped_after_stopped_by_watchpoint = 0;
+ break;
case infwait_normal_state:
/* See comments where a TARGET_WAITKIND_SYSCALL_RETURN event
break;
case infwait_nullified_state:
+ stepped_after_stopped_by_watchpoint = 0;
break;
case infwait_nonstep_watch_state:
in combination correctly? */
stepped_after_stopped_by_watchpoint = 1;
break;
+
+ default:
+ internal_error (__FILE__, __LINE__, "bad switch");
}
ecs->infwait_state = infwait_normal_state;
/* If it's a new process, add it to the thread database */
ecs->new_thread_event = (!ptid_equal (ecs->ptid, inferior_ptid)
+ && !ptid_equal (ecs->ptid, minus_one_ptid)
&& !in_thread_list (ecs->ptid));
if (ecs->ws.kind != TARGET_WAITKIND_EXITED
ui_out_text (uiout, "[New ");
ui_out_text (uiout, target_pid_or_tid_to_str (ecs->ptid));
ui_out_text (uiout, "]\n");
-
-#if 0
- /* NOTE: This block is ONLY meant to be invoked in case of a
- "thread creation event"! If it is invoked for any other
- sort of event (such as a new thread landing on a breakpoint),
- the event will be discarded, which is almost certainly
- a bad thing!
-
- To avoid this, the low-level module (eg. target_wait)
- should call in_thread_list and add_thread, so that the
- new thread is known by the time we get here. */
-
- /* We may want to consider not doing a resume here in order
- to give the user a chance to play with the new thread.
- It might be good to make that a user-settable option. */
-
- /* At this point, all threads are stopped (happens
- automatically in either the OS or the native code).
- Therefore we need to continue all threads in order to
- make progress. */
-
- target_resume (RESUME_ALL, 0, TARGET_SIGNAL_0);
- prepare_to_wait (ecs);
- return;
-#endif
}
switch (ecs->ws.kind)
might be the shell which has just loaded some objects,
otherwise add the symbols for the newly loaded objects. */
#ifdef SOLIB_ADD
- if (!stop_soon_quietly)
+ if (stop_soon == NO_STOP_QUIETLY)
{
/* Remove breakpoints, SOLIB_ADD might adjust
breakpoint addresses via breakpoint_re_set. */
terminal for any messages produced by
breakpoint_re_set. */
target_terminal_ours_for_output ();
- SOLIB_ADD (NULL, 0, NULL, auto_solib_add);
+ /* NOTE: cagney/2003-11-25: Make certain that the target
+ stack's section table is kept up-to-date. Architectures,
+ (e.g., PPC64), use the section table to perform
+ operations such as address => section name and hence
+ require the table to contain all sections (including
+ those found in shared libraries). */
+ /* NOTE: cagney/2003-11-25: Pass current_target and not
+ exec_ops to SOLIB_ADD. This is because current GDB is
+ only tooled to propagate section_table changes out from
+ the "current_target" (see target_resize_to_sections), and
+ not up from the exec stratum. This, of course, isn't
+ right. "infrun.c" should only interact with the
+ exec/process stratum, instead relying on the target stack
+ to propagate relevant changes (stop, section table
+ changed, ...) up to other layers. */
+ SOLIB_ADD (NULL, 0, ¤t_target, auto_solib_add);
target_terminal_inferior ();
/* Reinsert breakpoints and continue. */
/* The following are the only cases in which we keep going;
the above cases end in a continue or goto. */
case TARGET_WAITKIND_FORKED:
+ case TARGET_WAITKIND_VFORKED:
stop_signal = TARGET_SIGNAL_TRAP;
pending_follow.kind = ecs->ws.kind;
- pending_follow.fork_event.saw_child_fork = 1;
pending_follow.fork_event.parent_pid = PIDGET (ecs->ptid);
pending_follow.fork_event.child_pid = ecs->ws.value.related_pid;
- stop_pc = read_pc_pid (ecs->ptid);
- ecs->saved_inferior_ptid = inferior_ptid;
- inferior_ptid = ecs->ptid;
- /* The second argument of bpstat_stop_status is meant to help
- distinguish between a breakpoint trap and a singlestep trap.
- This is only important on targets where DECR_PC_AFTER_BREAK
- is non-zero. The prev_pc test is meant to distinguish between
- singlestepping a trap instruction, and singlestepping thru a
- jump to the instruction following a trap instruction. */
-
- stop_bpstat = bpstat_stop_status (&stop_pc,
- currently_stepping (ecs) &&
- prev_pc !=
- stop_pc - DECR_PC_AFTER_BREAK);
- ecs->random_signal = !bpstat_explains_signal (stop_bpstat);
- inferior_ptid = ecs->saved_inferior_ptid;
- goto process_event_stop_test;
+ stop_pc = read_pc ();
- /* If this a platform which doesn't allow a debugger to touch a
- vfork'd inferior until after it exec's, then we'd best keep
- our fingers entirely off the inferior, other than continuing
- it. This has the unfortunate side-effect that catchpoints
- of vforks will be ignored. But since the platform doesn't
- allow the inferior be touched at vfork time, there's really
- little choice. */
- case TARGET_WAITKIND_VFORKED:
- stop_signal = TARGET_SIGNAL_TRAP;
- pending_follow.kind = ecs->ws.kind;
+ stop_bpstat = bpstat_stop_status (stop_pc, ecs->ptid, 0);
- /* Is this a vfork of the parent? If so, then give any
- vfork catchpoints a chance to trigger now. (It's
- dangerous to do so if the child canot be touched until
- it execs, and the child has not yet exec'd. We probably
- should warn the user to that effect when the catchpoint
- triggers...) */
- if (ptid_equal (ecs->ptid, inferior_ptid))
- {
- pending_follow.fork_event.saw_parent_fork = 1;
- pending_follow.fork_event.parent_pid = PIDGET (ecs->ptid);
- pending_follow.fork_event.child_pid = ecs->ws.value.related_pid;
- }
+ ecs->random_signal = !bpstat_explains_signal (stop_bpstat);
- /* If we've seen the child's vfork event but cannot really touch
- the child until it execs, then we must continue the child now.
- Else, give any vfork catchpoints a chance to trigger now. */
- else
+ /* If no catchpoint triggered for this, then keep going. */
+ if (ecs->random_signal)
{
- pending_follow.fork_event.saw_child_fork = 1;
- pending_follow.fork_event.child_pid = PIDGET (ecs->ptid);
- pending_follow.fork_event.parent_pid = ecs->ws.value.related_pid;
- target_post_startup_inferior (pid_to_ptid
- (pending_follow.fork_event.
- child_pid));
+ stop_signal = TARGET_SIGNAL_0;
+ keep_going (ecs);
+ return;
}
-
- stop_pc = read_pc ();
- /* The second argument of bpstat_stop_status is meant to help
- distinguish between a breakpoint trap and a singlestep trap.
- This is only important on targets where DECR_PC_AFTER_BREAK
- is non-zero. The prev_pc test is meant to distinguish between
- singlestepping a trap instruction, and singlestepping thru a
- jump to the instruction following a trap instruction. */
-
- stop_bpstat = bpstat_stop_status (&stop_pc,
- currently_stepping (ecs) &&
- prev_pc !=
- stop_pc - DECR_PC_AFTER_BREAK);
- ecs->random_signal = !bpstat_explains_signal (stop_bpstat);
goto process_event_stop_test;
case TARGET_WAITKIND_EXECD:
stop_signal = TARGET_SIGNAL_TRAP;
/* NOTE drow/2002-12-05: This code should be pushed down into the
- target_wait function. Until then following vfork on HP/UX 10.20
- is probably broken by this. Of course, it's broken anyway. */
+ target_wait function. Until then following vfork on HP/UX 10.20
+ is probably broken by this. Of course, it's broken anyway. */
/* Is this a target which reports multiple exec events per actual
call to exec()? (HP-UX using ptrace does, for example.) If so,
ignore all but the last one. Just resume the exec'r, and wait
stop_pc = read_pc_pid (ecs->ptid);
ecs->saved_inferior_ptid = inferior_ptid;
inferior_ptid = ecs->ptid;
- /* The second argument of bpstat_stop_status is meant to help
- distinguish between a breakpoint trap and a singlestep trap.
- This is only important on targets where DECR_PC_AFTER_BREAK
- is non-zero. The prev_pc test is meant to distinguish between
- singlestepping a trap instruction, and singlestepping thru a
- jump to the instruction following a trap instruction. */
-
- stop_bpstat = bpstat_stop_status (&stop_pc,
- currently_stepping (ecs) &&
- prev_pc !=
- stop_pc - DECR_PC_AFTER_BREAK);
+
+ stop_bpstat = bpstat_stop_status (stop_pc, ecs->ptid, 0);
+
ecs->random_signal = !bpstat_explains_signal (stop_bpstat);
inferior_ptid = ecs->saved_inferior_ptid;
+
+ /* If no catchpoint triggered for this, then keep going. */
+ if (ecs->random_signal)
+ {
+ stop_signal = TARGET_SIGNAL_0;
+ keep_going (ecs);
+ return;
+ }
goto process_event_stop_test;
/* These syscall events are returned on HP-UX, as part of its
/* We had an event in the inferior, but we are not interested
in handling it at this level. The lower layers have already
done what needs to be done, if anything.
-
- One of the possible circumstances for this is when the
- inferior produces output for the console. The inferior has
- not stopped, and we are ignoring the event. Another possible
- circumstance is any event which the lower level knows will be
- reported multiple times without an intervening resume. */
+
+ One of the possible circumstances for this is when the
+ inferior produces output for the console. The inferior has
+ not stopped, and we are ignoring the event. Another possible
+ circumstance is any event which the lower level knows will be
+ reported multiple times without an intervening resume. */
case TARGET_WAITKIND_IGNORE:
prepare_to_wait (ecs);
return;
stop_pc = read_pc_pid (ecs->ptid);
+ if (stepping_past_singlestep_breakpoint)
+ {
+ gdb_assert (SOFTWARE_SINGLE_STEP_P ()
+ && singlestep_breakpoints_inserted_p);
+ gdb_assert (ptid_equal (singlestep_ptid, ecs->ptid));
+ gdb_assert (!ptid_equal (singlestep_ptid, saved_singlestep_ptid));
+
+ stepping_past_singlestep_breakpoint = 0;
+
+ /* We've either finished single-stepping past the single-step
+ breakpoint, or stopped for some other reason. It would be nice if
+ we could tell, but we can't reliably. */
+ if (stop_signal == TARGET_SIGNAL_TRAP)
+ {
+ /* Pull the single step breakpoints out of the target. */
+ SOFTWARE_SINGLE_STEP (0, 0);
+ singlestep_breakpoints_inserted_p = 0;
+
+ ecs->random_signal = 0;
+
+ ecs->ptid = saved_singlestep_ptid;
+ context_switch (ecs);
+ if (deprecated_context_hook)
+ deprecated_context_hook (pid_to_thread_id (ecs->ptid));
+
+ resume (1, TARGET_SIGNAL_0);
+ prepare_to_wait (ecs);
+ return;
+ }
+ }
+
+ stepping_past_singlestep_breakpoint = 0;
+
/* See if a thread hit a thread-specific breakpoint that was meant for
another thread. If so, then step that thread past the breakpoint,
and continue it. */
if (stop_signal == TARGET_SIGNAL_TRAP)
{
+ int thread_hop_needed = 0;
+
/* Check if a regular breakpoint has been hit before checking
for a potential single step breakpoint. Otherwise, GDB will
not see this breakpoint hit when stepping onto breakpoints. */
- if (breakpoints_inserted
- && breakpoint_here_p (stop_pc - DECR_PC_AFTER_BREAK))
+ if (breakpoints_inserted && breakpoint_here_p (stop_pc))
+ {
+ ecs->random_signal = 0;
+ if (!breakpoint_thread_match (stop_pc, ecs->ptid))
+ thread_hop_needed = 1;
+ }
+ else if (SOFTWARE_SINGLE_STEP_P () && singlestep_breakpoints_inserted_p)
{
ecs->random_signal = 0;
- if (!breakpoint_thread_match (stop_pc - DECR_PC_AFTER_BREAK,
- ecs->ptid))
+ /* The call to in_thread_list is necessary because PTIDs sometimes
+ change when we go from single-threaded to multi-threaded. If
+ the singlestep_ptid is still in the list, assume that it is
+ really different from ecs->ptid. */
+ if (!ptid_equal (singlestep_ptid, ecs->ptid)
+ && in_thread_list (singlestep_ptid))
{
- int remove_status;
-
- /* Saw a breakpoint, but it was hit by the wrong thread.
- Just continue. */
- if (DECR_PC_AFTER_BREAK)
- write_pc_pid (stop_pc - DECR_PC_AFTER_BREAK, ecs->ptid);
-
- remove_status = remove_breakpoints ();
- /* Did we fail to remove breakpoints? If so, try
- to set the PC past the bp. (There's at least
- one situation in which we can fail to remove
- the bp's: On HP-UX's that use ttrace, we can't
- change the address space of a vforking child
- process until the child exits (well, okay, not
- then either :-) or execs. */
- if (remove_status != 0)
- {
- /* FIXME! This is obviously non-portable! */
- write_pc_pid (stop_pc - DECR_PC_AFTER_BREAK + 4, ecs->ptid);
- /* We need to restart all the threads now,
- * unles we're running in scheduler-locked mode.
- * Use currently_stepping to determine whether to
- * step or continue.
- */
- /* FIXME MVS: is there any reason not to call resume()? */
- if (scheduler_mode == schedlock_on)
- target_resume (ecs->ptid,
- currently_stepping (ecs), TARGET_SIGNAL_0);
- else
- target_resume (RESUME_ALL,
- currently_stepping (ecs), TARGET_SIGNAL_0);
- prepare_to_wait (ecs);
- return;
- }
- else
- { /* Single step */
- breakpoints_inserted = 0;
- if (!ptid_equal (inferior_ptid, ecs->ptid))
- context_switch (ecs);
- ecs->waiton_ptid = ecs->ptid;
- ecs->wp = &(ecs->ws);
- ecs->another_trap = 1;
-
- ecs->infwait_state = infwait_thread_hop_state;
- keep_going (ecs);
- registers_changed ();
- return;
- }
+ thread_hop_needed = 1;
+ stepping_past_singlestep_breakpoint = 1;
+ saved_singlestep_ptid = singlestep_ptid;
}
}
- else if (SOFTWARE_SINGLE_STEP_P () && singlestep_breakpoints_inserted_p)
- {
- /* Readjust the stop_pc as it is off by DECR_PC_AFTER_BREAK
- compared to the value it would have if the system stepping
- capability was used. This allows the rest of the code in
- this function to use this address without having to worry
- whether software single step is in use or not. */
- if (DECR_PC_AFTER_BREAK)
- {
- stop_pc -= DECR_PC_AFTER_BREAK;
- write_pc_pid (stop_pc, ecs->ptid);
- }
-
- sw_single_step_trap_p = 1;
- ecs->random_signal = 0;
- }
- }
- else
- ecs->random_signal = 1;
-
- /* See if something interesting happened to the non-current thread. If
- so, then switch to that thread, and eventually give control back to
- the user.
-
- Note that if there's any kind of pending follow (i.e., of a fork,
- vfork or exec), we don't want to do this now. Rather, we'll let
- the next resume handle it. */
- if (!ptid_equal (ecs->ptid, inferior_ptid) &&
- (pending_follow.kind == TARGET_WAITKIND_SPURIOUS))
- {
- int printed = 0;
- /* If it's a random signal for a non-current thread, notify user
- if he's expressed an interest. */
- if (ecs->random_signal && signal_print[stop_signal])
+ if (thread_hop_needed)
{
-/* ??rehrauer: I don't understand the rationale for this code. If the
- inferior will stop as a result of this signal, then the act of handling
- the stop ought to print a message that's couches the stoppage in user
- terms, e.g., "Stopped for breakpoint/watchpoint". If the inferior
- won't stop as a result of the signal -- i.e., if the signal is merely
- a side-effect of something GDB's doing "under the covers" for the
- user, such as stepping threads over a breakpoint they shouldn't stop
- for -- then the message seems to be a serious annoyance at best.
-
- For now, remove the message altogether. */
-#if 0
- printed = 1;
- target_terminal_ours_for_output ();
- printf_filtered ("\nProgram received signal %s, %s.\n",
- target_signal_to_name (stop_signal),
- target_signal_to_string (stop_signal));
- gdb_flush (gdb_stdout);
-#endif
- }
+ int remove_status;
- /* If it's not SIGTRAP and not a signal we want to stop for, then
- continue the thread. */
+ /* Saw a breakpoint, but it was hit by the wrong thread.
+ Just continue. */
- if (stop_signal != TARGET_SIGNAL_TRAP && !signal_stop[stop_signal])
- {
- if (printed)
- target_terminal_inferior ();
+ if (SOFTWARE_SINGLE_STEP_P () && singlestep_breakpoints_inserted_p)
+ {
+ /* Pull the single step breakpoints out of the target. */
+ SOFTWARE_SINGLE_STEP (0, 0);
+ singlestep_breakpoints_inserted_p = 0;
+ }
- /* Clear the signal if it should not be passed. */
- if (signal_program[stop_signal] == 0)
- stop_signal = TARGET_SIGNAL_0;
+ remove_status = remove_breakpoints ();
+ /* Did we fail to remove breakpoints? If so, try
+ to set the PC past the bp. (There's at least
+ one situation in which we can fail to remove
+ the bp's: On HP-UX's that use ttrace, we can't
+ change the address space of a vforking child
+ process until the child exits (well, okay, not
+ then either :-) or execs. */
+ if (remove_status != 0)
+ {
+ /* FIXME! This is obviously non-portable! */
+ write_pc_pid (stop_pc + 4, ecs->ptid);
+ /* We need to restart all the threads now,
+ * unles we're running in scheduler-locked mode.
+ * Use currently_stepping to determine whether to
+ * step or continue.
+ */
+ /* FIXME MVS: is there any reason not to call resume()? */
+ if (scheduler_mode == schedlock_on)
+ target_resume (ecs->ptid,
+ currently_stepping (ecs), TARGET_SIGNAL_0);
+ else
+ target_resume (RESUME_ALL,
+ currently_stepping (ecs), TARGET_SIGNAL_0);
+ prepare_to_wait (ecs);
+ return;
+ }
+ else
+ { /* Single step */
+ breakpoints_inserted = 0;
+ if (!ptid_equal (inferior_ptid, ecs->ptid))
+ context_switch (ecs);
+ ecs->waiton_ptid = ecs->ptid;
+ ecs->wp = &(ecs->ws);
+ ecs->another_trap = 1;
- target_resume (ecs->ptid, 0, stop_signal);
- prepare_to_wait (ecs);
- return;
+ ecs->infwait_state = infwait_thread_hop_state;
+ keep_going (ecs);
+ registers_changed ();
+ return;
+ }
}
+ else if (SOFTWARE_SINGLE_STEP_P () && singlestep_breakpoints_inserted_p)
+ {
+ sw_single_step_trap_p = 1;
+ ecs->random_signal = 0;
+ }
+ }
+ else
+ ecs->random_signal = 1;
- /* It's a SIGTRAP or a signal we're interested in. Switch threads,
- and fall into the rest of wait_for_inferior(). */
-
+ /* See if something interesting happened to the non-current thread. If
+ so, then switch to that thread. */
+ if (!ptid_equal (ecs->ptid, inferior_ptid))
+ {
context_switch (ecs);
- if (context_hook)
- context_hook (pid_to_thread_id (ecs->ptid));
+ if (deprecated_context_hook)
+ deprecated_context_hook (pid_to_thread_id (ecs->ptid));
flush_cached_frames ();
}
includes evaluating watchpoints, things will come to a
stop in the correct manner. */
- if (DECR_PC_AFTER_BREAK)
- write_pc (stop_pc - DECR_PC_AFTER_BREAK);
-
remove_breakpoints ();
registers_changed ();
target_resume (ecs->ptid, 1, TARGET_SIGNAL_0); /* Single step */
/* It may be possible to simply continue after a watchpoint. */
if (HAVE_CONTINUABLE_WATCHPOINT)
- STOPPED_BY_WATCHPOINT (ecs->ws);
+ stopped_by_watchpoint = STOPPED_BY_WATCHPOINT (ecs->ws);
ecs->stop_func_start = 0;
ecs->stop_func_end = 0;
will both be 0 if it doesn't work. */
find_pc_partial_function (stop_pc, &ecs->stop_func_name,
&ecs->stop_func_start, &ecs->stop_func_end);
- ecs->stop_func_start += FUNCTION_START_OFFSET;
+ ecs->stop_func_start += DEPRECATED_FUNCTION_START_OFFSET;
ecs->another_trap = 0;
bpstat_clear (&stop_bpstat);
stop_step = 0;
will be made according to the signal handling tables. */
/* First, distinguish signals caused by the debugger from signals
- that have to do with the program's own actions.
- Note that breakpoint insns may cause SIGTRAP or SIGILL
- or SIGEMT, depending on the operating system version.
- Here we detect when a SIGILL or SIGEMT is really a breakpoint
- and change it to SIGTRAP. */
+ that have to do with the program's own actions. Note that
+ breakpoint insns may cause SIGTRAP or SIGILL or SIGEMT, depending
+ on the operating system version. Here we detect when a SIGILL or
+ SIGEMT is really a breakpoint and change it to SIGTRAP. We do
+ something similar for SIGSEGV, since a SIGSEGV will be generated
+ when we're trying to execute a breakpoint instruction on a
+ non-executable stack. This happens for call dummy breakpoints
+ for architectures like SPARC that place call dummies on the
+ stack. */
if (stop_signal == TARGET_SIGNAL_TRAP
- || (breakpoints_inserted &&
- (stop_signal == TARGET_SIGNAL_ILL
- || stop_signal == TARGET_SIGNAL_EMT)) || stop_soon_quietly)
+ || (breakpoints_inserted
+ && (stop_signal == TARGET_SIGNAL_ILL
+ || stop_signal == TARGET_SIGNAL_SEGV
+ || stop_signal == TARGET_SIGNAL_EMT))
+ || stop_soon == STOP_QUIETLY || stop_soon == STOP_QUIETLY_NO_SIGSTOP)
{
if (stop_signal == TARGET_SIGNAL_TRAP && stop_after_trap)
{
stop_stepping (ecs);
return;
}
- if (stop_soon_quietly)
+
+ /* This is originated from start_remote(), start_inferior() and
+ shared libraries hook functions. */
+ if (stop_soon == STOP_QUIETLY)
{
stop_stepping (ecs);
return;
}
- /* Don't even think about breakpoints
- if just proceeded over a breakpoint.
+ /* This originates from attach_command(). We need to overwrite
+ the stop_signal here, because some kernels don't ignore a
+ SIGSTOP in a subsequent ptrace(PTRACE_SONT,SOGSTOP) call.
+ See more comments in inferior.h. */
+ if (stop_soon == STOP_QUIETLY_NO_SIGSTOP)
+ {
+ stop_stepping (ecs);
+ if (stop_signal == TARGET_SIGNAL_STOP)
+ stop_signal = TARGET_SIGNAL_0;
+ return;
+ }
- However, if we are trying to proceed over a breakpoint
- and end up in sigtramp, then through_sigtramp_breakpoint
- will be set and we should check whether we've hit the
- step breakpoint. */
- if (stop_signal == TARGET_SIGNAL_TRAP && trap_expected
- && through_sigtramp_breakpoint == NULL)
+ /* Don't even think about breakpoints if just proceeded over a
+ breakpoint. */
+ if (stop_signal == TARGET_SIGNAL_TRAP && trap_expected)
bpstat_clear (&stop_bpstat);
else
{
/* See if there is a breakpoint at the current PC. */
+ stop_bpstat = bpstat_stop_status (stop_pc, ecs->ptid,
+ stopped_by_watchpoint);
- /* The second argument of bpstat_stop_status is meant to help
- distinguish between a breakpoint trap and a singlestep trap.
- This is only important on targets where DECR_PC_AFTER_BREAK
- is non-zero. The prev_pc test is meant to distinguish between
- singlestepping a trap instruction, and singlestepping thru a
- jump to the instruction following a trap instruction.
-
- Therefore, pass TRUE if our reason for stopping is
- something other than hitting a breakpoint. We do this by
- checking that either: we detected earlier a software single
- step trap or, 1) stepping is going on and 2) we didn't hit
- a breakpoint in a signal handler without an intervening stop
- in sigtramp, which is detected by a new stack pointer value
- below any usual function calling stack adjustments. */
- stop_bpstat =
- bpstat_stop_status
- (&stop_pc,
- sw_single_step_trap_p
- || (currently_stepping (ecs)
- && prev_pc != stop_pc - DECR_PC_AFTER_BREAK
- && !(step_range_end
- && INNER_THAN (read_sp (), (step_sp - 16)))));
/* Following in case break condition called a
function. */
stop_print_frame = 1;
}
+ /* NOTE: cagney/2003-03-29: These two checks for a random signal
+ at one stage in the past included checks for an inferior
+ function call's call dummy's return breakpoint. The original
+ comment, that went with the test, read:
+
+ ``End of a stack dummy. Some systems (e.g. Sony news) give
+ another signal besides SIGTRAP, so check here as well as
+ above.''
+
+ If someone ever tries to get get call dummys on a
+ non-executable stack to work (where the target would stop
+ with something like a SIGSEGV), then those tests might need
+ to be re-instated. Given, however, that the tests were only
+ enabled when momentary breakpoints were not being used, I
+ suspect that it won't be the case.
+
+ NOTE: kettenis/2004-02-05: Indeed such checks don't seem to
+ be necessary for call dummies on a non-executable stack on
+ SPARC. */
+
if (stop_signal == TARGET_SIGNAL_TRAP)
ecs->random_signal
= !(bpstat_explains_signal (stop_bpstat)
|| trap_expected
- || (!CALL_DUMMY_BREAKPOINT_OFFSET_P
- && DEPRECATED_PC_IN_CALL_DUMMY (stop_pc, read_sp (),
- get_frame_base (get_current_frame ())))
|| (step_range_end && step_resume_breakpoint == NULL));
-
else
{
- ecs->random_signal = !(bpstat_explains_signal (stop_bpstat)
- /* End of a stack dummy. Some systems (e.g. Sony
- news) give another signal besides SIGTRAP, so
- check here as well as above. */
- || (!CALL_DUMMY_BREAKPOINT_OFFSET_P
- && DEPRECATED_PC_IN_CALL_DUMMY (stop_pc, read_sp (),
- get_frame_base
- (get_current_frame
- ()))));
+ ecs->random_signal = !bpstat_explains_signal (stop_bpstat);
if (!ecs->random_signal)
stop_signal = TARGET_SIGNAL_TRAP;
}
else
ecs->random_signal = 1;
- /* If a fork, vfork or exec event was seen, then there are two
- possible responses we can make:
-
- 1. If a catchpoint triggers for the event (ecs->random_signal == 0),
- then we must stop now and issue a prompt. We will resume
- the inferior when the user tells us to.
- 2. If no catchpoint triggers for the event (ecs->random_signal == 1),
- then we must resume the inferior now and keep checking.
-
- In either case, we must take appropriate steps to "follow" the
- the fork/vfork/exec when the inferior is resumed. For example,
- if follow-fork-mode is "child", then we must detach from the
- parent inferior and follow the new child inferior.
-
- In either case, setting pending_follow causes the next resume()
- to take the appropriate following action. */
-process_event_stop_test:
- if (ecs->ws.kind == TARGET_WAITKIND_FORKED)
- {
- if (ecs->random_signal) /* I.e., no catchpoint triggered for this. */
- {
- trap_expected = 1;
- stop_signal = TARGET_SIGNAL_0;
- keep_going (ecs);
- return;
- }
- }
- else if (ecs->ws.kind == TARGET_WAITKIND_VFORKED)
- {
- if (ecs->random_signal) /* I.e., no catchpoint triggered for this. */
- {
- stop_signal = TARGET_SIGNAL_0;
- keep_going (ecs);
- return;
- }
- }
- else if (ecs->ws.kind == TARGET_WAITKIND_EXECD)
- {
- pending_follow.kind = ecs->ws.kind;
- if (ecs->random_signal) /* I.e., no catchpoint triggered for this. */
- {
- trap_expected = 1;
- stop_signal = TARGET_SIGNAL_0;
- keep_going (ecs);
- return;
- }
- }
+process_event_stop_test:
/* For the program's own signals, act according to
the signal handling tables. */
if (signal_program[stop_signal] == 0)
stop_signal = TARGET_SIGNAL_0;
- /* I'm not sure whether this needs to be check_sigtramp2 or
- whether it could/should be keep_going.
-
- This used to jump to step_over_function if we are stepping,
- which is wrong.
-
- Suppose the user does a `next' over a function call, and while
- that call is in progress, the inferior receives a signal for
- which GDB does not stop (i.e., signal_stop[SIG] is false). In
- that case, when we reach this point, there is already a
- step-resume breakpoint established, right where it should be:
- immediately after the function call the user is "next"-ing
- over. If we call step_over_function now, two bad things
- happen:
-
- - we'll create a new breakpoint, at wherever the current
- frame's return address happens to be. That could be
- anywhere, depending on what function call happens to be on
- the top of the stack at that point. Point is, it's probably
- not where we need it.
-
- - the existing step-resume breakpoint (which is at the correct
- address) will get orphaned: step_resume_breakpoint will point
- to the new breakpoint, and the old step-resume breakpoint
- will never be cleaned up.
-
- The old behavior was meant to help HP-UX single-step out of
- sigtramps. It would place the new breakpoint at prev_pc, which
- was certainly wrong. I don't know the details there, so fixing
- this probably breaks that. As with anything else, it's up to
- the HP-UX maintainer to furnish a fix that doesn't break other
- platforms. --JimB, 20 May 1999 */
- check_sigtramp2 (ecs);
+ if (prev_pc == read_pc ()
+ && !breakpoints_inserted
+ && breakpoint_here_p (read_pc ())
+ && step_resume_breakpoint == NULL)
+ {
+ /* We were just starting a new sequence, attempting to
+ single-step off of a breakpoint and expecting a SIGTRAP.
+ Intead this signal arrives. This signal will take us out
+ of the stepping range so GDB needs to remember to, when
+ the signal handler returns, resume stepping off that
+ breakpoint. */
+ /* To simplify things, "continue" is forced to use the same
+ code paths as single-step - set a breakpoint at the
+ signal return address and then, once hit, step off that
+ breakpoint. */
+ insert_step_resume_breakpoint_at_frame (get_current_frame ());
+ ecs->step_after_step_resume_breakpoint = 1;
+ }
+ else if (step_range_end != 0
+ && stop_signal != TARGET_SIGNAL_0
+ && stop_pc >= step_range_start && stop_pc < step_range_end
+ && frame_id_eq (get_frame_id (get_current_frame ()),
+ step_frame_id))
+ {
+ /* The inferior is about to take a signal that will take it
+ out of the single step range. Set a breakpoint at the
+ current PC (which is presumably where the signal handler
+ will eventually return) and then allow the inferior to
+ run free.
+
+ Note that this is only needed for a signal delivered
+ while in the single-step range. Nested signals aren't a
+ problem as they eventually all return. */
+ insert_step_resume_breakpoint_at_frame (get_current_frame ());
+ }
keep_going (ecs);
return;
}
if (what.call_dummy)
{
stop_stack_dummy = 1;
-#ifdef HP_OS_BUG
- trap_expected_after_continue = 1;
-#endif
}
switch (what.main_action)
{
delete_step_resume_breakpoint (&step_resume_breakpoint);
}
- /* Not sure whether we need to blow this away too, but probably
- it is like the step-resume breakpoint. */
- if (through_sigtramp_breakpoint != NULL)
- {
- delete_breakpoint (through_sigtramp_breakpoint);
- through_sigtramp_breakpoint = NULL;
- }
-#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
-#endif /* 0 */
- set_longjmp_resume_breakpoint (jmp_buf_pc, null_frame_id);
+ set_longjmp_resume_breakpoint (jmp_buf_pc, null_frame_id);
ecs->handling_longjmp = 1; /* FIXME */
keep_going (ecs);
return;
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
- && (frame_id_inner (get_frame_id (get_current_frame ()),
- step_frame_id)))
- {
- ecs->another_trap = 1;
- keep_going (ecs);
- return;
- }
-#endif /* 0 */
disable_longjmp_breakpoint ();
ecs->handling_longjmp = 0; /* FIXME */
if (what.main_action == BPSTAT_WHAT_CLEAR_LONGJMP_RESUME)
case BPSTAT_WHAT_STOP_NOISY:
stop_print_frame = 1;
- /* We are about to nuke the step_resume_breakpoint and
- through_sigtramp_breakpoint via the cleanup chain, so
- no need to worry about it here. */
+ /* We are about to nuke the step_resume_breakpointt via the
+ cleanup chain, so no need to worry about it here. */
stop_stepping (ecs);
return;
case BPSTAT_WHAT_STOP_SILENT:
stop_print_frame = 0;
- /* We are about to nuke the step_resume_breakpoint and
- through_sigtramp_breakpoint via the cleanup chain, so
- no need to worry about it here. */
+ /* We are about to nuke the step_resume_breakpoin via the
+ cleanup chain, so no need to worry about it here. */
stop_stepping (ecs);
return;
bpstat_find_step_resume_breakpoint (stop_bpstat);
}
delete_step_resume_breakpoint (&step_resume_breakpoint);
+ if (ecs->step_after_step_resume_breakpoint)
+ {
+ /* Back when the step-resume breakpoint was inserted, we
+ were trying to single-step off a breakpoint. Go back
+ to doing that. */
+ ecs->step_after_step_resume_breakpoint = 0;
+ remove_breakpoints ();
+ breakpoints_inserted = 0;
+ ecs->another_trap = 1;
+ keep_going (ecs);
+ return;
+ }
break;
case BPSTAT_WHAT_THROUGH_SIGTRAMP:
- if (through_sigtramp_breakpoint)
- delete_breakpoint (through_sigtramp_breakpoint);
- through_sigtramp_breakpoint = NULL;
-
/* If were waiting for a trap, hitting the step_resume_break
doesn't count as getting it. */
if (trap_expected)
terminal for any messages produced by
breakpoint_re_set. */
target_terminal_ours_for_output ();
- SOLIB_ADD (NULL, 0, NULL, auto_solib_add);
+ /* NOTE: cagney/2003-11-25: Make certain that the target
+ stack's section table is kept up-to-date. Architectures,
+ (e.g., PPC64), use the section table to perform
+ operations such as address => section name and hence
+ require the table to contain all sections (including
+ those found in shared libraries). */
+ /* NOTE: cagney/2003-11-25: Pass current_target and not
+ exec_ops to SOLIB_ADD. This is because current GDB is
+ only tooled to propagate section_table changes out from
+ the "current_target" (see target_resize_to_sections), and
+ not up from the exec stratum. This, of course, isn't
+ right. "infrun.c" should only interact with the
+ exec/process stratum, instead relying on the target stack
+ to propagate relevant changes (stop, section table
+ changed, ...) up to other layers. */
+ SOLIB_ADD (NULL, 0, ¤t_target, auto_solib_add);
target_terminal_inferior ();
/* Try to reenable shared library breakpoints, additional
gdb of events. This allows the user to get control
and place breakpoints in initializer routines for
dynamically loaded objects (among other things). */
- if (stop_on_solib_events)
+ if (stop_on_solib_events || stop_stack_dummy)
{
stop_stepping (ecs);
return;
the call that caused this catchpoint to trigger. That
gives the user a more useful vantage from which to
examine their program's state. */
- else if (what.main_action ==
- BPSTAT_WHAT_CHECK_SHLIBS_RESUME_FROM_HOOK)
+ else if (what.main_action
+ == BPSTAT_WHAT_CHECK_SHLIBS_RESUME_FROM_HOOK)
{
/* ??rehrauer: If I could figure out how to get the
right return PC from here, we could just set a temp
return;
}
- if (!CALL_DUMMY_BREAKPOINT_OFFSET_P)
- {
- /* This is the old way of detecting the end of the stack dummy.
- An architecture which defines CALL_DUMMY_BREAKPOINT_OFFSET gets
- handled above. As soon as we can test it on all of them, all
- architectures should define it. */
-
- /* If this is the breakpoint at the end of a stack dummy,
- just stop silently, unless the user was doing an si/ni, in which
- case she'd better know what she's doing. */
-
- if (CALL_DUMMY_HAS_COMPLETED (stop_pc, read_sp (),
- get_frame_base (get_current_frame ()))
- && !step_range_end)
- {
- stop_print_frame = 0;
- stop_stack_dummy = 1;
-#ifdef HP_OS_BUG
- trap_expected_after_continue = 1;
-#endif
- stop_stepping (ecs);
- return;
- }
- }
-
if (step_resume_breakpoint)
{
/* Having a step-resume breakpoint overrides anything
else having to do with stepping commands until
that breakpoint is reached. */
- /* I'm not sure whether this needs to be check_sigtramp2 or
- whether it could/should be keep_going. */
- check_sigtramp2 (ecs);
keep_going (ecs);
return;
}
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. */
- check_sigtramp2 (ecs);
keep_going (ecs);
return;
}
within it! */
if (stop_pc >= step_range_start && stop_pc < step_range_end)
{
- /* We might be doing a BPSTAT_WHAT_SINGLE and getting a signal.
- So definately need to check for sigtramp here. */
- check_sigtramp2 (ecs);
keep_going (ecs);
return;
}
if (step_over_calls == STEP_OVER_UNDEBUGGABLE
&& IN_SOLIB_DYNSYM_RESOLVE_CODE (stop_pc))
{
- CORE_ADDR pc_after_resolver = SKIP_SOLIB_RESOLVER (stop_pc);
+ CORE_ADDR pc_after_resolver =
+ gdbarch_skip_solib_resolver (current_gdbarch, stop_pc);
if (pc_after_resolver)
{
init_sal (&sr_sal);
sr_sal.pc = pc_after_resolver;
- check_for_old_step_resume_breakpoint ();
- step_resume_breakpoint =
- set_momentary_breakpoint (sr_sal, null_frame_id, bp_step_resume);
- if (breakpoints_inserted)
- insert_breakpoints ();
+ insert_step_resume_breakpoint_at_sal (sr_sal, null_frame_id);
}
keep_going (ecs);
return;
}
- /* We can't update step_sp every time through the loop, because
- reading the stack pointer would slow down stepping too much.
- But we can update it every time we leave the step range. */
- ecs->update_step_sp = 1;
-
- /* Did we just take a signal? */
- if (PC_IN_SIGTRAMP (stop_pc, ecs->stop_func_name)
- && !PC_IN_SIGTRAMP (prev_pc, prev_func_name)
- && INNER_THAN (read_sp (), step_sp))
+ if (step_range_end != 1
+ && (step_over_calls == STEP_OVER_UNDEBUGGABLE
+ || step_over_calls == STEP_OVER_ALL)
+ && get_frame_type (get_current_frame ()) == SIGTRAMP_FRAME)
{
- /* We've just taken a signal; go until we are back to
- the point where we took it and one more. */
-
- /* Note: The test above succeeds not only when we stepped
- into a signal handler, but also when we step past the last
- statement of a signal handler and end up in the return stub
- of the signal handler trampoline. To distinguish between
- these two cases, check that the frame is INNER_THAN the
- previous one below. pai/1997-09-11 */
-
-
- {
- struct frame_id current_frame = get_frame_id (get_current_frame ());
-
- if (frame_id_inner (current_frame, step_frame_id))
- {
- /* We have just taken a signal; go until we are back to
- the point where we took it and one more. */
-
- /* This code is needed at least in the following case:
- The user types "next" and then a signal arrives (before
- the "next" is done). */
-
- /* Note that if we are stopped at a breakpoint, then we need
- the step_resume breakpoint to override any breakpoints at
- the same location, so that we will still step over the
- breakpoint even though the signal happened. */
- struct symtab_and_line sr_sal;
-
- init_sal (&sr_sal);
- sr_sal.symtab = NULL;
- sr_sal.line = 0;
- sr_sal.pc = prev_pc;
- /* We could probably be setting the frame to
- step_frame_id; I don't think anyone thought to try it. */
- check_for_old_step_resume_breakpoint ();
- step_resume_breakpoint =
- set_momentary_breakpoint (sr_sal, null_frame_id, bp_step_resume);
- if (breakpoints_inserted)
- insert_breakpoints ();
- }
- else
- {
- /* We just stepped out of a signal handler and into
- its calling trampoline.
-
- Normally, we'd call step_over_function from
- here, but for some reason GDB can't unwind the
- stack correctly to find the real PC for the point
- user code where the signal trampoline will return
- -- FRAME_SAVED_PC fails, at least on HP-UX 10.20.
- But signal trampolines are pretty small stubs of
- code, anyway, so it's OK instead to just
- single-step out. Note: assuming such trampolines
- don't exhibit recursion on any platform... */
- find_pc_partial_function (stop_pc, &ecs->stop_func_name,
- &ecs->stop_func_start,
- &ecs->stop_func_end);
- /* Readjust stepping range */
- step_range_start = ecs->stop_func_start;
- step_range_end = ecs->stop_func_end;
- ecs->stepping_through_sigtramp = 1;
- }
- }
-
-
- /* 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;
-
- ecs->remove_breakpoints_on_following_step = 1;
+ /* The inferior, while doing a "step" or "next", has ended up in
+ a signal trampoline (either by a signal being delivered or by
+ the signal handler returning). Just single-step until the
+ inferior leaves the trampoline (either by calling the handler
+ or returning). */
keep_going (ecs);
return;
}
- if (stop_pc == ecs->stop_func_start /* Quick test */
- || (in_prologue (stop_pc, ecs->stop_func_start) &&
- !IN_SOLIB_RETURN_TRAMPOLINE (stop_pc, ecs->stop_func_name))
- || IN_SOLIB_CALL_TRAMPOLINE (stop_pc, ecs->stop_func_name)
- || ecs->stop_func_name == 0)
+ if (frame_id_eq (frame_unwind_id (get_current_frame ()), step_frame_id))
{
/* It's a subroutine call. */
+ CORE_ADDR real_stop_pc;
if ((step_over_calls == STEP_OVER_NONE)
|| ((step_range_end == 1)
/* I presume that step_over_calls is only 0 when we're
supposed to be stepping at the assembly language level
("stepi"). Just stop. */
- /* Also, maybe we just did a "nexti" inside a prolog,
- so we thought it was a subroutine call but it was not.
- Stop as well. FENN */
+ /* Also, maybe we just did a "nexti" inside a prolog, so we
+ thought it was a subroutine call but it was not. Stop as
+ well. FENN */
stop_step = 1;
print_stop_reason (END_STEPPING_RANGE, 0);
stop_stepping (ecs);
return;
}
- if (step_over_calls == STEP_OVER_ALL || IGNORE_HELPER_CALL (stop_pc))
+#ifdef DEPRECATED_IGNORE_HELPER_CALL
+ /* On MIPS16, a function that returns a floating point value may
+ call a library helper function to copy the return value to a
+ floating point register. The DEPRECATED_IGNORE_HELPER_CALL
+ macro returns non-zero if we should ignore (i.e. step over)
+ this function call. */
+ /* FIXME: cagney/2004-07-21: These custom ``ignore frame when
+ stepping'' function attributes (SIGTRAMP_FRAME,
+ DEPRECATED_IGNORE_HELPER_CALL, SKIP_TRAMPOLINE_CODE,
+ skip_language_trampoline frame, et.al.) need to be replaced
+ with generic attributes bound to the frame's function. */
+ if (DEPRECATED_IGNORE_HELPER_CALL (stop_pc))
{
- /* We're doing a "next". */
-
- if (PC_IN_SIGTRAMP (stop_pc, ecs->stop_func_name)
- && frame_id_inner (step_frame_id,
- frame_id_build (read_sp (), 0)))
- /* We stepped out of a signal handler, and into its
- calling trampoline. This is misdetected as a
- subroutine call, but stepping over the signal
- trampoline isn't such a bad idea. In order to do that,
- we have to ignore the value in step_frame_id, since
- that doesn't represent the frame that'll reach when we
- return from the signal trampoline. Otherwise we'll
- probably continue to the end of the program. */
- step_frame_id = null_frame_id;
-
- step_over_function (ecs);
+ /* We're doing a "next", set a breakpoint at callee's return
+ address (the address at which the caller will
+ resume). */
+ insert_step_resume_breakpoint_at_frame (get_prev_frame (get_current_frame ()));
+ keep_going (ecs);
+ return;
+ }
+#endif
+ if (step_over_calls == STEP_OVER_ALL)
+ {
+ /* We're doing a "next", set a breakpoint at callee's return
+ address (the address at which the caller will
+ resume). */
+ insert_step_resume_breakpoint_at_frame (get_prev_frame (get_current_frame ()));
keep_going (ecs);
return;
}
- /* If we are in a function call trampoline (a stub between
- the calling routine and the real function), locate the real
+ /* 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)
- ecs->stop_func_start = tmp;
- else
+ into it at all, and (b) what prologue we want to run to the
+ end of, if we do step into it. */
+ real_stop_pc = skip_language_trampoline (stop_pc);
+ if (real_stop_pc == 0)
+ real_stop_pc = SKIP_TRAMPOLINE_CODE (stop_pc);
+ if (real_stop_pc != 0)
+ ecs->stop_func_start = real_stop_pc;
+
+ if (IN_SOLIB_DYNSYM_RESOLVE_CODE (ecs->stop_func_start))
{
- tmp = DYNAMIC_TRAMPOLINE_NEXTPC (stop_pc);
- if (tmp)
- {
- struct symtab_and_line xxx;
- /* Why isn't this s_a_l called "sr_sal", like all of the
- other s_a_l's where this code is duplicated? */
- init_sal (&xxx); /* initialize to zeroes */
- xxx.pc = tmp;
- xxx.section = find_pc_overlay (xxx.pc);
- check_for_old_step_resume_breakpoint ();
- step_resume_breakpoint =
- set_momentary_breakpoint (xxx, null_frame_id, bp_step_resume);
- insert_breakpoints ();
- keep_going (ecs);
- return;
- }
+ struct symtab_and_line sr_sal;
+ init_sal (&sr_sal);
+ sr_sal.pc = ecs->stop_func_start;
+
+ insert_step_resume_breakpoint_at_sal (sr_sal, null_frame_id);
+ keep_going (ecs);
+ return;
}
- /* If we have line number information for the function we
- are thinking of stepping into, step into it.
+ /* 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
}
}
- /* If we have no line number and the step-stop-if-no-debug
- is set, we stop the step so that the user has a chance to
- switch in assembly mode. */
+ /* If we have no line number and the step-stop-if-no-debug is
+ set, we stop the step so that the user has a chance to switch
+ in assembly mode. */
if (step_over_calls == STEP_OVER_UNDEBUGGABLE && step_stop_if_no_debug)
{
stop_step = 1;
return;
}
- step_over_function (ecs);
+ /* Set a breakpoint at callee's return address (the address at
+ which the caller will resume). */
+ insert_step_resume_breakpoint_at_frame (get_prev_frame (get_current_frame ()));
keep_going (ecs);
return;
-
- }
-
- /* We've wandered out of the step range. */
-
- ecs->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;
- print_stop_reason (END_STEPPING_RANGE, 0);
- stop_stepping (ecs);
- return;
}
/* If we're in the return path from a shared library trampoline,
we want to proceed through the trampoline when stepping. */
if (IN_SOLIB_RETURN_TRAMPOLINE (stop_pc, ecs->stop_func_name))
{
- CORE_ADDR tmp;
-
/* Determine where this trampoline returns. */
- tmp = SKIP_TRAMPOLINE_CODE (stop_pc);
+ CORE_ADDR real_stop_pc = SKIP_TRAMPOLINE_CODE (stop_pc);
/* Only proceed through if we know where it's going. */
- if (tmp)
+ if (real_stop_pc)
{
/* And put the step-breakpoint there and go until there. */
struct symtab_and_line sr_sal;
init_sal (&sr_sal); /* initialize to zeroes */
- sr_sal.pc = tmp;
+ sr_sal.pc = real_stop_pc;
sr_sal.section = find_pc_overlay (sr_sal.pc);
- /* 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. */
- check_for_old_step_resume_breakpoint ();
- step_resume_breakpoint =
- set_momentary_breakpoint (sr_sal, null_frame_id, bp_step_resume);
- if (breakpoints_inserted)
- insert_breakpoints ();
+
+ /* 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. */
+ insert_step_resume_breakpoint_at_sal (sr_sal, null_frame_id);
/* Restart without fiddling with the step ranges or
other state. */
}
}
+ /* NOTE: tausq/2004-05-24: This if block used to be done before all
+ the trampoline processing logic, however, there are some trampolines
+ that have no names, so we should do trampoline handling first. */
+ if (step_over_calls == STEP_OVER_UNDEBUGGABLE
+ && ecs->stop_func_name == NULL)
+ {
+ /* The inferior just stepped into, or returned to, an
+ undebuggable function (where there is no symbol, not even a
+ minimal symbol, corresponding to the address where the
+ inferior stopped). Since we want to skip this kind of code,
+ we keep going until the inferior returns from this
+ function. */
+ if (step_stop_if_no_debug)
+ {
+ /* If we have no line number and the step-stop-if-no-debug
+ is set, we stop the step so that the user has a chance to
+ switch in assembly mode. */
+ stop_step = 1;
+ print_stop_reason (END_STEPPING_RANGE, 0);
+ stop_stepping (ecs);
+ return;
+ }
+ else
+ {
+ /* Set a breakpoint at callee's return address (the address
+ at which the caller will resume). */
+ insert_step_resume_breakpoint_at_frame (get_prev_frame (get_current_frame ()));
+ keep_going (ecs);
+ return;
+ }
+ }
+
+ if (step_range_end == 1)
+ {
+ /* It is stepi or nexti. We always want to stop stepping after
+ one instruction. */
+ stop_step = 1;
+ print_stop_reason (END_STEPPING_RANGE, 0);
+ stop_stepping (ecs);
+ return;
+ }
+
+ ecs->sal = find_pc_line (stop_pc, 0);
+
if (ecs->sal.line == 0)
{
/* We have no line number information. That means to stop
/* In the case where we just stepped out of a function into the
middle of a line of the caller, continue stepping, but
step_frame_id must be modified to current frame */
+#if 0
+ /* NOTE: cagney/2003-10-16: I think this frame ID inner test is too
+ generous. It will trigger on things like a step into a frameless
+ stackless leaf function. I think the logic should instead look
+ at the unwound frame ID has that should give a more robust
+ indication of what happened. */
+ if (step - ID == current - ID)
+ still stepping in same function;
+ else if (step - ID == unwind (current - ID))
+ stepped into a function;
+ else
+ stepped out of a function;
+ /* Of course this assumes that the frame ID unwind code is robust
+ and we're willing to introduce frame unwind logic into this
+ function. Fortunately, those days are nearly upon us. */
+#endif
{
struct frame_id current_frame = get_frame_id (get_current_frame ());
if (!(frame_id_inner (current_frame, step_frame_id)))
static int
currently_stepping (struct execution_control_state *ecs)
{
- return ((through_sigtramp_breakpoint == NULL
- && !ecs->handling_longjmp
+ return ((!ecs->handling_longjmp
&& ((step_range_end && step_resume_breakpoint == NULL)
|| trap_expected))
|| ecs->stepping_through_solib_after_catch
|| bpstat_should_step ());
}
-static void
-check_sigtramp2 (struct execution_control_state *ecs)
-{
- if (trap_expected
- && PC_IN_SIGTRAMP (stop_pc, ecs->stop_func_name)
- && !PC_IN_SIGTRAMP (prev_pc, prev_func_name)
- && INNER_THAN (read_sp (), step_sp))
- {
- /* What has happened here is that we have just stepped the
- inferior with a signal (because it is a signal which
- shouldn't make 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. 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 the testsuite,
- gdb.base/signals.exp where it says "exceedingly difficult"). */
-
- struct symtab_and_line sr_sal;
-
- init_sal (&sr_sal); /* initialize to zeroes */
- sr_sal.pc = prev_pc;
- sr_sal.section = find_pc_overlay (sr_sal.pc);
- /* We perhaps could set the frame if we kept track of what the
- frame corresponding to prev_pc was. But we don't, so don't. */
- through_sigtramp_breakpoint =
- set_momentary_breakpoint (sr_sal, null_frame_id, bp_through_sigtramp);
- if (breakpoints_inserted)
- insert_breakpoints ();
-
- ecs->remove_breakpoints_on_following_step = 1;
- ecs->another_trap = 1;
- }
-}
-
/* Subroutine call with source code we should not step over. Do step
to the first line of code in it. */
/* If the prologue ends in the middle of a source line, continue to
the end of that source line (if it is still within the function).
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. */
-#else
if (ecs->sal.end
&& ecs->sal.pc != ecs->stop_func_start
&& ecs->sal.end < ecs->stop_func_end)
ecs->stop_func_start = ecs->sal.end;
-#endif
+
+ /* Architectures which require breakpoint adjustment might not be able
+ to place a breakpoint at the computed address. If so, the test
+ ``ecs->stop_func_start == stop_pc'' will never succeed. Adjust
+ ecs->stop_func_start to an address at which a breakpoint may be
+ legitimately placed.
+
+ Note: kevinb/2004-01-19: On FR-V, if this adjustment is not
+ made, GDB will enter an infinite loop when stepping through
+ optimized code consisting of VLIW instructions which contain
+ subinstructions corresponding to different source lines. On
+ FR-V, it's not permitted to place a breakpoint on any but the
+ first subinstruction of a VLIW instruction. When a breakpoint is
+ set, GDB will adjust the breakpoint address to the beginning of
+ the VLIW instruction. Thus, we need to make the corresponding
+ adjustment here when computing the stop address. */
+
+ if (gdbarch_adjust_breakpoint_address_p (current_gdbarch))
+ {
+ ecs->stop_func_start
+ = gdbarch_adjust_breakpoint_address (current_gdbarch,
+ ecs->stop_func_start);
+ }
if (ecs->stop_func_start == stop_pc)
{
init_sal (&sr_sal); /* initialize to zeroes */
sr_sal.pc = ecs->stop_func_start;
sr_sal.section = find_pc_overlay (ecs->stop_func_start);
+
/* 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. */
- check_for_old_step_resume_breakpoint ();
- step_resume_breakpoint =
- set_momentary_breakpoint (sr_sal, null_frame_id, bp_step_resume);
- if (breakpoints_inserted)
- insert_breakpoints ();
+ insert_step_resume_breakpoint_at_sal (sr_sal, null_frame_id);
/* And make sure stepping stops right away then. */
step_range_end = step_range_start;
keep_going (ecs);
}
-/* We've just entered a callee, and we wish to resume until it returns
- to the caller. Setting a step_resume breakpoint on the return
- address will catch a return from the callee.
-
- However, if the callee is recursing, we want to be careful not to
- catch returns of those recursive calls, but only of THIS instance
- of the call.
+/* Insert a "step resume breakpoint" at SR_SAL with frame ID SR_ID.
+ This is used to both functions and to skip over code. */
+
+static void
+insert_step_resume_breakpoint_at_sal (struct symtab_and_line sr_sal,
+ struct frame_id sr_id)
+{
+ /* There should never be more than one step-resume breakpoint per
+ thread, so we should never be setting a new
+ step_resume_breakpoint when one is already active. */
+ gdb_assert (step_resume_breakpoint == NULL);
+ step_resume_breakpoint = set_momentary_breakpoint (sr_sal, sr_id,
+ bp_step_resume);
+ if (breakpoints_inserted)
+ insert_breakpoints ();
+}
+
+/* Insert a "step resume breakpoint" at RETURN_FRAME.pc. This is used
+ to skip a function (next, skip-no-debug) or signal. It's assumed
+ that the function/signal handler being skipped eventually returns
+ to the breakpoint inserted at RETURN_FRAME.pc.
+
+ For the skip-function case, the function may have been reached by
+ either single stepping a call / return / signal-return instruction,
+ or by hitting a breakpoint. In all cases, the RETURN_FRAME belongs
+ to the skip-function's caller.
- To do this, we set the step_resume bp's frame to our current
- caller's frame (step_frame_id, which is set by the "next" or
- "until" command, before execution begins). */
+ For the signals case, this is called with the interrupted
+ function's frame. The signal handler, when it returns, will resume
+ the interrupted function at RETURN_FRAME.pc. */
static void
-step_over_function (struct execution_control_state *ecs)
+insert_step_resume_breakpoint_at_frame (struct frame_info *return_frame)
{
struct symtab_and_line sr_sal;
init_sal (&sr_sal); /* initialize to zeros */
- sr_sal.pc = ADDR_BITS_REMOVE (SAVED_PC_AFTER_CALL (get_current_frame ()));
- sr_sal.section = find_pc_overlay (sr_sal.pc);
-
- check_for_old_step_resume_breakpoint ();
- step_resume_breakpoint =
- set_momentary_breakpoint (sr_sal, get_frame_id (get_current_frame ()),
- bp_step_resume);
- if (frame_id_p (step_frame_id)
- && !IN_SOLIB_DYNSYM_RESOLVE_CODE (sr_sal.pc))
- step_resume_breakpoint->frame_id = step_frame_id;
+ sr_sal.pc = ADDR_BITS_REMOVE (get_frame_pc (return_frame));
+ sr_sal.section = find_pc_overlay (sr_sal.pc);
- if (breakpoints_inserted)
- insert_breakpoints ();
+ insert_step_resume_breakpoint_at_sal (sr_sal, get_frame_id (return_frame));
}
static void
stop_stepping (struct execution_control_state *ecs)
{
- if (target_has_execution)
- {
- /* Are we stopping for a vfork event? We only stop when we see
- the child's event. However, we may not yet have seen the
- parent's event. And, inferior_ptid is still set to the
- parent's pid, until we resume again and follow either the
- parent or child.
-
- To ensure that we can really touch inferior_ptid (aka, the
- parent process) -- which calls to functions like read_pc
- implicitly do -- wait on the parent if necessary. */
- if ((pending_follow.kind == TARGET_WAITKIND_VFORKED)
- && !pending_follow.fork_event.saw_parent_fork)
- {
- ptid_t parent_ptid;
-
- do
- {
- if (target_wait_hook)
- parent_ptid = target_wait_hook (pid_to_ptid (-1), &(ecs->ws));
- else
- parent_ptid = target_wait (pid_to_ptid (-1), &(ecs->ws));
- }
- while (!ptid_equal (parent_ptid, inferior_ptid));
- }
-
- /* Assuming the inferior still exists, set these up for next
- time, just like we did above if we didn't break out of the
- loop. */
- prev_pc = read_pc ();
- prev_func_start = ecs->stop_func_start;
- prev_func_name = ecs->stop_func_name;
- }
-
/* Let callers know we don't want to wait for the inferior anymore. */
ecs->wait_some_more = 0;
}
{
/* Save the pc before execution, to compare with pc after stop. */
prev_pc = read_pc (); /* Might have been DECR_AFTER_BREAK */
- prev_func_start = ecs->stop_func_start; /* Ok, since if DECR_PC_AFTER
- BREAK is defined, the
- original pc would not have
- been at the start of a
- function. */
- prev_func_name = ecs->stop_func_name;
-
- if (ecs->update_step_sp)
- step_sp = read_sp ();
- ecs->update_step_sp = 0;
/* If we did not do break;, it means we should keep running the
inferior and not return to debugger. */
The signal was SIGTRAP, e.g. it was our signal, but we
decided we should resume from it.
- We're going to run this baby now!
+ We're going to run this baby now! */
- Insert breakpoints now, unless we are trying 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_breakpoint == NULL
- && through_sigtramp_breakpoint == NULL
- && ecs->remove_breakpoints_on_following_step)
- {
- ecs->remove_breakpoints_on_following_step = 0;
- remove_breakpoints ();
- breakpoints_inserted = 0;
- }
- else if (!breakpoints_inserted &&
- (through_sigtramp_breakpoint != NULL || !ecs->another_trap))
+ if (!breakpoints_inserted && !ecs->another_trap)
{
breakpoints_failed = insert_breakpoints ();
if (breakpoints_failed)
if (stop_signal == TARGET_SIGNAL_TRAP && !signal_program[stop_signal])
stop_signal = TARGET_SIGNAL_0;
-#ifdef SHIFT_INST_REGS
- /* I'm not sure when this following segment applies. I do know,
- now, that we shouldn't rewrite the regs when we were stopped
- by a random signal from the inferior process. */
- /* FIXME: Shouldn't this be based on the valid bit of the SXIP?
- (this is only used on the 88k). */
-
- if (!bpstat_explains_signal (stop_bpstat)
- && (stop_signal != TARGET_SIGNAL_CHLD) && !stopped_by_random_signal)
- SHIFT_INST_REGS ();
-#endif /* SHIFT_INST_REGS */
resume (currently_stepping (ecs), stop_signal);
}
void
normal_stop (void)
{
+ struct target_waitstatus last;
+ ptid_t last_ptid;
+
+ get_last_target_status (&last_ptid, &last);
+
/* As with the notification of thread events, we want to delay
notifying the user that we've switched thread context until
the inferior actually stops.
- (Note that there's no point in saying anything if the inferior
- has exited!) */
+ There's no point in saying anything if the inferior has exited.
+ Note that SIGNALLED here means "exited with a signal", not
+ "received a signal". */
if (!ptid_equal (previous_inferior_ptid, inferior_ptid)
- && target_has_execution)
+ && target_has_execution
+ && last.kind != TARGET_WAITKIND_SIGNALLED
+ && last.kind != TARGET_WAITKIND_EXITED)
{
target_terminal_ours_for_output ();
printf_filtered ("[Switching to %s]\n",
previous_inferior_ptid = inferior_ptid;
}
+ /* NOTE drow/2004-01-17: Is this still necessary? */
/* Make sure that the current_frame's pc is correct. This
is a correction for setting up the frame info before doing
DECR_PC_AFTER_BREAK */
- if (target_has_execution && get_current_frame ())
- (get_current_frame ())->pc = read_pc ();
+ if (target_has_execution)
+ /* FIXME: cagney/2002-12-06: Has the PC changed? Thanks to
+ DECR_PC_AFTER_BREAK, the program counter can change. Ask the
+ frame code to check for this and sort out any resultant mess.
+ DECR_PC_AFTER_BREAK needs to just go away. */
+ deprecated_update_frame_pc_hack (get_current_frame (), read_pc ());
if (target_has_execution && breakpoints_inserted)
{
{
case PRINT_UNKNOWN:
/* FIXME: cagney/2002-12-01: Given that a frame ID does
- (or should) carry around the function and does (or
- should) use that when doing a frame comparison. */
+ (or should) carry around the function and does (or
+ should) use that when doing a frame comparison. */
if (stop_step
&& frame_id_eq (step_frame_id,
get_frame_id (get_current_frame ()))
LOCATION: Print only location
SRC_AND_LOC: Print location and source line */
if (do_frame_printing)
- show_and_print_stack_frame (deprecated_selected_frame, -1, source_flag);
+ print_stack_frame (get_selected_frame (NULL), 0, source_flag);
/* Display the auto-display expressions. */
do_displays ();
if (stop_stack_dummy)
{
- /* Pop the empty frame that contains the stack dummy.
- POP_FRAME ends with a setting of the current frame, so we
- can use that next. */
- POP_FRAME;
+ /* Pop the empty frame that contains the stack dummy. POP_FRAME
+ ends with a setting of the current frame, so we can use that
+ next. */
+ frame_pop (get_current_frame ());
/* Set stop_pc to what it was before we called the function.
Can't rely on restore_inferior_status because that only gets
called if we don't stop in the called function. */
done:
annotate_stopped ();
+ observer_notify_normal_stop (stop_bpstat);
}
static int
enum step_over_calls_kind step_over_calls;
CORE_ADDR step_resume_break_address;
int stop_after_trap;
- int stop_soon_quietly;
+ int stop_soon;
struct regcache *stop_registers;
/* These are here because if call_function_by_hand has written some
write_inferior_status_register (struct inferior_status *inf_status, int regno,
LONGEST val)
{
- int size = REGISTER_RAW_SIZE (regno);
+ int size = register_size (current_gdbarch, regno);
void *buf = alloca (size);
store_signed_integer (buf, size, val);
regcache_raw_write (inf_status->registers, regno, buf);
inf_status->step_frame_id = step_frame_id;
inf_status->step_over_calls = step_over_calls;
inf_status->stop_after_trap = stop_after_trap;
- inf_status->stop_soon_quietly = stop_soon_quietly;
+ inf_status->stop_soon = stop_soon;
/* Save original bpstat chain here; replace it with copy of chain.
If caller's caller is walking the chain, they'll be happier if we
hand them back the original chain when restore_inferior_status is
step_frame_id = inf_status->step_frame_id;
step_over_calls = inf_status->step_over_calls;
stop_after_trap = inf_status->stop_after_trap;
- stop_soon_quietly = inf_status->stop_soon_quietly;
+ stop_soon = inf_status->stop_soon;
bpstat_clear (&stop_bpstat);
stop_bpstat = inf_status->stop_bpstat;
breakpoint_proceeded = inf_status->breakpoint_proceeded;
void
_initialize_infrun (void)
{
- register int i;
- register int numsigs;
+ int i;
+ int numsigs;
struct cmd_list_element *c;
- register_gdbarch_swap (&stop_registers, sizeof (stop_registers), NULL);
- register_gdbarch_swap (NULL, 0, build_infrun);
+ DEPRECATED_REGISTER_GDBARCH_SWAP (stop_registers);
+ deprecated_register_gdbarch_swap (NULL, 0, build_infrun);
add_info ("signals", signals_info,
"What debugger does when program gets various signals.\n\
signal_print[TARGET_SIGNAL_CANCEL] = 0;
#ifdef SOLIB_ADD
- add_show_from_set
+ deprecated_add_show_from_set
(add_set_cmd ("stop-on-solib-events", class_support, var_zinteger,
(char *) &stop_on_solib_events,
"Set stopping for shared library events.\n\
c = add_set_enum_cmd ("follow-fork-mode",
class_run,
follow_fork_mode_kind_names, &follow_fork_mode_string,
-/* ??rehrauer: The "both" option is broken, by what may be a 10.20
- kernel problem. It's also not terribly useful without a GUI to
- help the user drive two debuggers. So for now, I'm disabling
- the "both" option. */
-/* "Set debugger response to a program call of fork \
- or vfork.\n\
- A fork or vfork creates a new process. follow-fork-mode can be:\n\
- parent - the original process is debugged after a fork\n\
- child - the new process is debugged after a fork\n\
- both - both the parent and child are debugged after a fork\n\
- ask - the debugger will ask for one of the above choices\n\
- For \"both\", another copy of the debugger will be started to follow\n\
- the new child process. The original debugger will continue to follow\n\
- the original parent process. To distinguish their prompts, the\n\
- debugger copy's prompt will be changed.\n\
- For \"parent\" or \"child\", the unfollowed process will run free.\n\
- By default, the debugger will follow the parent process.",
- */
"Set debugger response to a program call of fork \
or vfork.\n\
A fork or vfork creates a new process. follow-fork-mode can be:\n\
parent - the original process is debugged after a fork\n\
child - the new process is debugged after a fork\n\
- ask - the debugger will ask for one of the above choices\n\
-For \"parent\" or \"child\", the unfollowed process will run free.\n\
+The unfollowed process will continue to run.\n\
By default, the debugger will follow the parent process.", &setlist);
- add_show_from_set (c, &showlist);
+ deprecated_add_show_from_set (c, &showlist);
c = add_set_enum_cmd ("scheduler-locking", class_run, scheduler_enums, /* array of string names */
&scheduler_mode, /* current mode */
Other threads may run while stepping over a function call ('next').", &setlist);
set_cmd_sfunc (c, set_schedlock_func); /* traps on target vector */
- add_show_from_set (c, &showlist);
+ deprecated_add_show_from_set (c, &showlist);
c = add_set_cmd ("step-mode", class_run,
var_boolean, (char *) &step_stop_if_no_debug,
function without debug line information will stop at the first\n\
instruction of that function. Otherwise, the function is skipped and\n\
the step command stops at a different source line.", &setlist);
- add_show_from_set (c, &showlist);
+ deprecated_add_show_from_set (c, &showlist);
/* ptid initializations */
null_ptid = ptid_build (0, 0, 0);
projects / deliverable / binutils-gdb.git / blobdiff