/* Cache and manage frames for GDB, the GNU debugger.
- Copyright 1986, 1987, 1989, 1991, 1994, 1995, 1996, 1998, 2000,
- 2001, 2002, 2003, 2004 Free Software Foundation, Inc.
+ Copyright (C) 1986, 1987, 1989, 1991, 1994, 1995, 1996, 1998, 2000, 2001,
+ 2002, 2003, 2004, 2007 Free Software Foundation, Inc.
This file is part of GDB.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
- Foundation, Inc., 59 Temple Place - Suite 330,
- Boston, MA 02111-1307, USA. */
+ Foundation, Inc., 51 Franklin Street, Fifth Floor,
+ Boston, MA 02110-1301, USA. */
#include "defs.h"
#include "frame.h"
struct frame_info *next; /* down, inner, younger */
int prev_p;
struct frame_info *prev; /* up, outer, older */
+
+ /* The reason why we could not set PREV, or UNWIND_NO_REASON if we
+ could. Only valid when PREV_P is set. */
+ enum unwind_stop_reason stop_reason;
};
/* Flag to control debugging. */
static int frame_debug;
+static void
+show_frame_debug (struct ui_file *file, int from_tty,
+ struct cmd_list_element *c, const char *value)
+{
+ fprintf_filtered (file, _("Frame debugging is %s.\n"), value);
+}
/* Flag to indicate whether backtraces should stop at main et.al. */
static int backtrace_past_main;
+static void
+show_backtrace_past_main (struct ui_file *file, int from_tty,
+ struct cmd_list_element *c, const char *value)
+{
+ fprintf_filtered (file, _("\
+Whether backtraces should continue past \"main\" is %s.\n"),
+ value);
+}
+
static int backtrace_past_entry;
-static unsigned int backtrace_limit = UINT_MAX;
+static void
+show_backtrace_past_entry (struct ui_file *file, int from_tty,
+ struct cmd_list_element *c, const char *value)
+{
+ fprintf_filtered (file, _("\
+Whether backtraces should continue past the entry point of a program is %s.\n"),
+ value);
+}
+
+static int backtrace_limit = INT_MAX;
+static void
+show_backtrace_limit (struct ui_file *file, int from_tty,
+ struct cmd_list_element *c, const char *value)
+{
+ fprintf_filtered (file, _("\
+An upper bound on the number of backtrace levels is %s.\n"),
+ value);
+}
+
static void
fprint_field (struct ui_file *file, const char *name, int p, CORE_ADDR addr)
}
static int
-do_frame_register_read (void *src, int regnum, void *buf)
+do_frame_register_read (void *src, int regnum, gdb_byte *buf)
{
frame_register_read (src, regnum, buf);
return 1;
void
frame_register_unwind (struct frame_info *frame, int regnum,
int *optimizedp, enum lval_type *lvalp,
- CORE_ADDR *addrp, int *realnump, void *bufferp)
+ CORE_ADDR *addrp, int *realnump, gdb_byte *bufferp)
{
struct frame_unwind_cache *cache;
void
frame_register (struct frame_info *frame, int regnum,
int *optimizedp, enum lval_type *lvalp,
- CORE_ADDR *addrp, int *realnump, void *bufferp)
+ CORE_ADDR *addrp, int *realnump, gdb_byte *bufferp)
{
/* Require all but BUFFERP to be valid. A NULL BUFFERP indicates
that the value proper does not need to be fetched. */
}
void
-frame_unwind_register (struct frame_info *frame, int regnum, void *buf)
+frame_unwind_register (struct frame_info *frame, int regnum, gdb_byte *buf)
{
int optimized;
CORE_ADDR addr;
void
get_frame_register (struct frame_info *frame,
- int regnum, void *buf)
+ int regnum, gdb_byte *buf)
{
frame_unwind_register (frame->next, regnum, buf);
}
LONGEST
frame_unwind_register_signed (struct frame_info *frame, int regnum)
{
- char buf[MAX_REGISTER_SIZE];
+ gdb_byte buf[MAX_REGISTER_SIZE];
frame_unwind_register (frame, regnum, buf);
return extract_signed_integer (buf, register_size (get_frame_arch (frame),
regnum));
ULONGEST
frame_unwind_register_unsigned (struct frame_info *frame, int regnum)
{
- char buf[MAX_REGISTER_SIZE];
+ gdb_byte buf[MAX_REGISTER_SIZE];
frame_unwind_register (frame, regnum, buf);
return extract_unsigned_integer (buf, register_size (get_frame_arch (frame),
regnum));
frame_unwind_unsigned_register (struct frame_info *frame, int regnum,
ULONGEST *val)
{
- char buf[MAX_REGISTER_SIZE];
+ gdb_byte buf[MAX_REGISTER_SIZE];
frame_unwind_register (frame, regnum, buf);
(*val) = extract_unsigned_integer (buf,
register_size (get_frame_arch (frame),
}
void
-put_frame_register (struct frame_info *frame, int regnum, const void *buf)
+put_frame_register (struct frame_info *frame, int regnum,
+ const gdb_byte *buf)
{
struct gdbarch *gdbarch = get_frame_arch (frame);
int realnum;
{
/* FIXME: write_memory doesn't yet take constant buffers.
Arrrg! */
- char tmp[MAX_REGISTER_SIZE];
+ gdb_byte tmp[MAX_REGISTER_SIZE];
memcpy (tmp, buf, register_size (gdbarch, regnum));
write_memory (addr, tmp, register_size (gdbarch, regnum));
break;
Returns 0 if the register value could not be found. */
int
-frame_register_read (struct frame_info *frame, int regnum, void *myaddr)
+frame_register_read (struct frame_info *frame, int regnum,
+ gdb_byte *myaddr)
{
int optimized;
enum lval_type lval;
return !optimized;
}
+int
+get_frame_register_bytes (struct frame_info *frame, int regnum,
+ CORE_ADDR offset, int len, gdb_byte *myaddr)
+{
+ struct gdbarch *gdbarch = get_frame_arch (frame);
+
+ /* Skip registers wholly inside of OFFSET. */
+ while (offset >= register_size (gdbarch, regnum))
+ {
+ offset -= register_size (gdbarch, regnum);
+ regnum++;
+ }
+
+ /* Copy the data. */
+ while (len > 0)
+ {
+ int curr_len = register_size (gdbarch, regnum) - offset;
+ if (curr_len > len)
+ curr_len = len;
+
+ if (curr_len == register_size (gdbarch, regnum))
+ {
+ if (!frame_register_read (frame, regnum, myaddr))
+ return 0;
+ }
+ else
+ {
+ gdb_byte buf[MAX_REGISTER_SIZE];
+ if (!frame_register_read (frame, regnum, buf))
+ return 0;
+ memcpy (myaddr, buf + offset, curr_len);
+ }
+
+ myaddr += curr_len;
+ len -= curr_len;
+ offset = 0;
+ regnum++;
+ }
+
+ return 1;
+}
+
+void
+put_frame_register_bytes (struct frame_info *frame, int regnum,
+ CORE_ADDR offset, int len, const gdb_byte *myaddr)
+{
+ struct gdbarch *gdbarch = get_frame_arch (frame);
+
+ /* Skip registers wholly inside of OFFSET. */
+ while (offset >= register_size (gdbarch, regnum))
+ {
+ offset -= register_size (gdbarch, regnum);
+ regnum++;
+ }
+
+ /* Copy the data. */
+ while (len > 0)
+ {
+ int curr_len = register_size (gdbarch, regnum) - offset;
+ if (curr_len > len)
+ curr_len = len;
+
+ if (curr_len == register_size (gdbarch, regnum))
+ {
+ put_frame_register (frame, regnum, myaddr);
+ }
+ else
+ {
+ gdb_byte buf[MAX_REGISTER_SIZE];
+ frame_register_read (frame, regnum, buf);
+ memcpy (buf + offset, myaddr, curr_len);
+ put_frame_register (frame, regnum, buf);
+ }
+
+ myaddr += curr_len;
+ len -= curr_len;
+ offset = 0;
+ regnum++;
+ }
+}
/* Map between a frame register number and its name. A frame register
space is a superset of the cooked register space --- it also
paddr_nz (addr), paddr_nz (pc));
}
- fi = frame_obstack_zalloc (sizeof (struct frame_info));
+ fi = FRAME_OBSTACK_ZALLOC (struct frame_info);
fi->next = create_sentinel_frame (current_regcache);
}
}
+/* Find where a register is saved (in memory or another register).
+ The result of frame_register_unwind is just where it is saved
+ relative to this particular frame. */
+
+static void
+frame_register_unwind_location (struct frame_info *this_frame, int regnum,
+ int *optimizedp, enum lval_type *lvalp,
+ CORE_ADDR *addrp, int *realnump)
+{
+ gdb_assert (this_frame == NULL || this_frame->level >= 0);
+
+ while (this_frame != NULL)
+ {
+ frame_register_unwind (this_frame, regnum, optimizedp, lvalp,
+ addrp, realnump, NULL);
+
+ if (*optimizedp)
+ break;
+
+ if (*lvalp != lval_register)
+ break;
+
+ regnum = *realnump;
+ this_frame = get_next_frame (this_frame);
+ }
+}
+
/* Return a "struct frame_info" corresponding to the frame that called
THIS_FRAME. Returns NULL if there is no such frame.
return this_frame->prev;
}
this_frame->prev_p = 1;
+ this_frame->stop_reason = UNWIND_NO_REASON;
/* Check that this frame's ID was valid. If it wasn't, don't try to
unwind to the prev frame. Be careful to not apply this test to
fprint_frame (gdb_stdlog, NULL);
fprintf_unfiltered (gdb_stdlog, " // this ID is NULL }\n");
}
+ this_frame->stop_reason = UNWIND_NULL_ID;
return NULL;
}
if (this_frame->next->level >= 0
&& this_frame->next->unwind->type != SIGTRAMP_FRAME
&& frame_id_inner (this_id, get_frame_id (this_frame->next)))
- error (_("Previous frame inner to this frame (corrupt stack?)"));
+ {
+ if (frame_debug)
+ {
+ fprintf_unfiltered (gdb_stdlog, "-> ");
+ fprint_frame (gdb_stdlog, NULL);
+ fprintf_unfiltered (gdb_stdlog, " // this frame ID is inner }\n");
+ }
+ this_frame->stop_reason = UNWIND_INNER_ID;
+ return NULL;
+ }
/* Check that this and the next frame are not identical. If they
are, there is most likely a stack cycle. As with the inner-than
test above, avoid comparing the inner-most and sentinel frames. */
if (this_frame->level > 0
&& frame_id_eq (this_id, get_frame_id (this_frame->next)))
- error (_("Previous frame identical to this frame (corrupt stack?)"));
+ {
+ if (frame_debug)
+ {
+ fprintf_unfiltered (gdb_stdlog, "-> ");
+ fprint_frame (gdb_stdlog, NULL);
+ fprintf_unfiltered (gdb_stdlog, " // this frame has same ID }\n");
+ }
+ this_frame->stop_reason = UNWIND_SAME_ID;
+ return NULL;
+ }
+
+ /* Check that this and the next frame do not unwind the PC register
+ to the same memory location. If they do, then even though they
+ have different frame IDs, the new frame will be bogus; two
+ functions can't share a register save slot for the PC. This can
+ happen when the prologue analyzer finds a stack adjustment, but
+ no PC save.
+
+ This check does assume that the "PC register" is roughly a
+ traditional PC, even if the gdbarch_unwind_pc method adjusts
+ it (we do not rely on the value, only on the unwound PC being
+ dependent on this value). A potential improvement would be
+ to have the frame prev_pc method and the gdbarch unwind_pc
+ method set the same lval and location information as
+ frame_register_unwind. */
+ if (this_frame->level > 0
+ && PC_REGNUM >= 0
+ && get_frame_type (this_frame) == NORMAL_FRAME
+ && get_frame_type (this_frame->next) == NORMAL_FRAME)
+ {
+ int optimized, realnum;
+ enum lval_type lval, nlval;
+ CORE_ADDR addr, naddr;
+
+ frame_register_unwind_location (this_frame, PC_REGNUM, &optimized,
+ &lval, &addr, &realnum);
+ frame_register_unwind_location (get_next_frame (this_frame), PC_REGNUM,
+ &optimized, &nlval, &naddr, &realnum);
+
+ if (lval == lval_memory && lval == nlval && addr == naddr)
+ {
+ if (frame_debug)
+ {
+ fprintf_unfiltered (gdb_stdlog, "-> ");
+ fprint_frame (gdb_stdlog, NULL);
+ fprintf_unfiltered (gdb_stdlog, " // no saved PC }\n");
+ }
+
+ this_frame->stop_reason = UNWIND_NO_SAVED_PC;
+ this_frame->prev = NULL;
+ return NULL;
+ }
+ }
/* Allocate the new frame but do not wire it in to the frame chain.
Some (bad) code in INIT_FRAME_EXTRA_INFO tries to look along
return NULL;
}
- if (this_frame->level > backtrace_limit)
+ /* If the user's backtrace limit has been exceeded, stop. We must
+ add two to the current level; one of those accounts for backtrace_limit
+ being 1-based and the level being 0-based, and the other accounts for
+ the level of the new frame instead of the level of the current
+ frame. */
+ if (this_frame->level + 2 > backtrace_limit)
{
- error (_("Backtrace limit of %d exceeded"), backtrace_limit);
+ frame_debug_got_null_frame (gdb_stdlog, this_frame,
+ "backtrace limit exceeded");
+ return NULL;
}
/* If we're already inside the entry function for the main objfile,
/* Memory access methods. */
void
-get_frame_memory (struct frame_info *this_frame, CORE_ADDR addr, void *buf,
- int len)
+get_frame_memory (struct frame_info *this_frame, CORE_ADDR addr,
+ gdb_byte *buf, int len)
{
read_memory (addr, buf, len);
}
int
safe_frame_unwind_memory (struct frame_info *this_frame,
- CORE_ADDR addr, void *buf, int len)
+ CORE_ADDR addr, gdb_byte *buf, int len)
{
- /* NOTE: deprecated_read_memory_nobpt returns zero on success! */
- return !deprecated_read_memory_nobpt (addr, buf, len);
+ /* NOTE: read_memory_nobpt returns zero on success! */
+ return !read_memory_nobpt (addr, buf, len);
}
/* Architecture method. */
internal_error (__FILE__, __LINE__, _("Missing unwind SP method"));
}
+/* Return the reason why we can't unwind past FRAME. */
+
+enum unwind_stop_reason
+get_frame_unwind_stop_reason (struct frame_info *frame)
+{
+ /* If we haven't tried to unwind past this point yet, then assume
+ that unwinding would succeed. */
+ if (frame->prev_p == 0)
+ return UNWIND_NO_REASON;
+
+ /* Otherwise, we set a reason when we succeeded (or failed) to
+ unwind. */
+ return frame->stop_reason;
+}
+
+/* Return a string explaining REASON. */
+
+const char *
+frame_stop_reason_string (enum unwind_stop_reason reason)
+{
+ switch (reason)
+ {
+ case UNWIND_NULL_ID:
+ return _("unwinder did not report frame ID");
+
+ case UNWIND_INNER_ID:
+ return _("previous frame inner to this frame (corrupt stack?)");
+
+ case UNWIND_SAME_ID:
+ return _("previous frame identical to this frame (corrupt stack?)");
+
+ case UNWIND_NO_SAVED_PC:
+ return _("frame did not save the PC");
+
+ case UNWIND_NO_REASON:
+ case UNWIND_FIRST_ERROR:
+ default:
+ internal_error (__FILE__, __LINE__,
+ "Invalid frame stop reason");
+ }
+}
+
extern initialize_file_ftype _initialize_frame; /* -Wmissing-prototypes */
static struct cmd_list_element *set_backtrace_cmdlist;
observer_attach_target_changed (frame_observer_target_changed);
- add_prefix_cmd ("backtrace", class_maintenance, set_backtrace_cmd, "\
+ add_prefix_cmd ("backtrace", class_maintenance, set_backtrace_cmd, _("\
Set backtrace specific variables.\n\
-Configure backtrace variables such as the backtrace limit",
+Configure backtrace variables such as the backtrace limit"),
&set_backtrace_cmdlist, "set backtrace ",
0/*allow-unknown*/, &setlist);
- add_prefix_cmd ("backtrace", class_maintenance, show_backtrace_cmd, "\
+ add_prefix_cmd ("backtrace", class_maintenance, show_backtrace_cmd, _("\
Show backtrace specific variables\n\
-Show backtrace variables such as the backtrace limit",
+Show backtrace variables such as the backtrace limit"),
&show_backtrace_cmdlist, "show backtrace ",
0/*allow-unknown*/, &showlist);
Normally the caller of \"main\" is not of interest, so GDB will terminate\n\
the backtrace at \"main\". Set this variable if you need to see the rest\n\
of the stack trace."),
- NULL, /* FIXME: i18n: Whether backtraces should continue past \"main\" is %s. */
- NULL, NULL, &set_backtrace_cmdlist,
+ NULL,
+ show_backtrace_past_main,
+ &set_backtrace_cmdlist,
&show_backtrace_cmdlist);
add_setshow_boolean_cmd ("past-entry", class_obscure,
Normally there are no callers beyond the entry point of a program, so GDB\n\
will terminate the backtrace there. Set this variable if you need to see \n\
the rest of the stack trace."),
- NULL, /* FIXME: i18n: Whether backtraces should continue past the entry point is %s. */
- NULL, NULL, &set_backtrace_cmdlist,
+ NULL,
+ show_backtrace_past_entry,
+ &set_backtrace_cmdlist,
&show_backtrace_cmdlist);
- add_setshow_uinteger_cmd ("limit", class_obscure,
- &backtrace_limit, _("\
+ add_setshow_integer_cmd ("limit", class_obscure,
+ &backtrace_limit, _("\
Set an upper bound on the number of backtrace levels."), _("\
Show the upper bound on the number of backtrace levels."), _("\
No more than the specified number of frames can be displayed or examined.\n\
Zero is unlimited."),
- NULL, /* FIXME: i18n: An upper bound on the number of backtrace levels is %s. */
- NULL, NULL, &set_backtrace_cmdlist,
- &show_backtrace_cmdlist);
+ NULL,
+ show_backtrace_limit,
+ &set_backtrace_cmdlist,
+ &show_backtrace_cmdlist);
/* Debug this files internals. */
- deprecated_add_show_from_set
- (add_set_cmd ("frame", class_maintenance, var_zinteger,
- &frame_debug, "Set frame debugging.\n\
-When non-zero, frame specific internal debugging is enabled.", &setdebuglist),
- &showdebuglist);
+ add_setshow_zinteger_cmd ("frame", class_maintenance, &frame_debug, _("\
+Set frame debugging."), _("\
+Show frame debugging."), _("\
+When non-zero, frame specific internal debugging is enabled."),
+ NULL,
+ show_frame_debug,
+ &setdebuglist, &showdebuglist);
}
projects / deliverable / binutils-gdb.git / blobdiff