/* Cache and manage frames for GDB, the GNU debugger.
- Copyright 1986, 1987, 1989, 1991, 1994, 1995, 1996, 1998, 2000,
- 2001, 2002, 2003 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"
#include "frame-base.h"
#include "command.h"
#include "gdbcmd.h"
+#include "observer.h"
+#include "objfiles.h"
+#include "exceptions.h"
+
+static struct frame_info *get_prev_frame_1 (struct frame_info *this_frame);
/* We keep a cache of stack frames, each of which is a "struct
frame_info". The innermost one gets allocated (in
increases. This is a cached value. It could just as easily be
computed by counting back from the selected frame to the inner
most frame. */
- /* NOTE: cagney/2002-04-05: Perhaphs a level of ``-1'' should be
+ /* NOTE: cagney/2002-04-05: Perhaps a level of ``-1'' should be
reserved to indicate a bogus frame - one that has been created
just to keep GDB happy (GDB always needs a frame). For the
moment leave this as speculation. */
int level;
- /* The frame's type. */
- /* FIXME: cagney/2003-04-02: Should instead be returning
- ->unwind->type. Unfortunatly, legacy code is still explicitly
- setting the type using the method deprecated_set_frame_type.
- Eliminate that method and this field can be eliminated. */
- enum frame_type type;
-
- /* For each register, address of where it was saved on entry to the
- frame, or zero if it was not saved on entry to this frame. This
- includes special registers such as pc and fp saved in special
- ways in the stack frame. The SP_REGNUM is even more special, the
- address here is the sp for the previous frame, not the address
- where the sp was saved. */
- /* Allocated by frame_saved_regs_zalloc () which is called /
- initialized by DEPRECATED_FRAME_INIT_SAVED_REGS(). */
- CORE_ADDR *saved_regs; /*NUM_REGS + NUM_PSEUDO_REGS*/
-
- /* Anything extra for this structure that may have been defined in
- the machine dependent files. */
- /* Allocated by frame_extra_info_zalloc () which is called /
- initialized by DEPRECATED_INIT_EXTRA_FRAME_INFO */
- struct frame_extra_info *extra_info;
-
- /* If dwarf2 unwind frame informations is used, this structure holds
- all related unwind data. */
- struct context *context;
-
/* The frame's low-level unwinder and corresponding cache. The
low-level unwinder is responsible for unwinding register values
for the previous frame. The low-level unwind methods are
- selected based on the presence, or otherwize, of register unwind
+ selected based on the presence, or otherwise, of register unwind
information such as CFI. */
void *prologue_cache;
const struct frame_unwind *unwind;
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 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);
+}
-/* Flag to indicate whether backtraces should stop at main. */
-static int backtrace_below_main;
+static void
+fprint_field (struct ui_file *file, const char *name, int p, CORE_ADDR addr)
+{
+ if (p)
+ fprintf_unfiltered (file, "%s=0x%s", name, paddr_nz (addr));
+ else
+ fprintf_unfiltered (file, "!%s", name);
+}
void
fprint_frame_id (struct ui_file *file, struct frame_id id)
{
- fprintf_unfiltered (file, "{stack=0x%s,code=0x%s}",
- paddr_nz (id.stack_addr),
- paddr_nz (id.code_addr));
+ fprintf_unfiltered (file, "{");
+ fprint_field (file, "stack", id.stack_addr_p, id.stack_addr);
+ fprintf_unfiltered (file, ",");
+ fprint_field (file, "code", id.code_addr_p, id.code_addr);
+ fprintf_unfiltered (file, ",");
+ fprint_field (file, "special", id.special_addr_p, id.special_addr);
+ fprintf_unfiltered (file, "}");
}
static void
{
switch (type)
{
- case UNKNOWN_FRAME:
- fprintf_unfiltered (file, "UNKNOWN_FRAME");
- return;
case NORMAL_FRAME:
fprintf_unfiltered (file, "NORMAL_FRAME");
return;
fprintf_unfiltered (file, "level=%d", fi->level);
fprintf_unfiltered (file, ",");
fprintf_unfiltered (file, "type=");
- fprint_frame_type (file, fi->type);
+ if (fi->unwind != NULL)
+ fprint_frame_type (file, fi->unwind->type);
+ else
+ fprintf_unfiltered (file, "<unknown>");
fprintf_unfiltered (file, ",");
fprintf_unfiltered (file, "unwind=");
if (fi->unwind != NULL)
}
if (!fi->this_id.p)
{
- gdb_assert (!legacy_frame_p (current_gdbarch));
if (frame_debug)
fprintf_unfiltered (gdb_stdlog, "{ get_frame_id (fi=%d) ",
fi->level);
/* Find the unwinder. */
if (fi->unwind == NULL)
- {
- fi->unwind = frame_unwind_find_by_pc (current_gdbarch,
- get_frame_pc (fi));
- /* FIXME: cagney/2003-04-02: Rather than storing the frame's
- type in the frame, the unwinder's type should be returned
- directly. Unfortunatly, legacy code, called by
- legacy_get_prev_frame, explicitly set the frames type
- using the method deprecated_set_frame_type(). */
- gdb_assert (fi->unwind->type != UNKNOWN_FRAME);
- fi->type = fi->unwind->type;
- }
+ fi->unwind = frame_unwind_find_by_frame (fi->next,
+ &fi->prologue_cache);
/* Find THIS frame's ID. */
fi->unwind->this_id (fi->next, &fi->prologue_cache, &fi->this_id.value);
fi->this_id.p = 1;
return fi->this_id.value;
}
+struct frame_id
+frame_unwind_id (struct frame_info *next_frame)
+{
+ /* Use prev_frame, and not get_prev_frame. The latter will truncate
+ the frame chain, leading to this function unintentionally
+ returning a null_frame_id (e.g., when a caller requests the frame
+ ID of "main()"s caller. */
+ return get_frame_id (get_prev_frame_1 (next_frame));
+}
+
const struct frame_id null_frame_id; /* All zeros. */
+struct frame_id
+frame_id_build_special (CORE_ADDR stack_addr, CORE_ADDR code_addr,
+ CORE_ADDR special_addr)
+{
+ struct frame_id id = null_frame_id;
+ id.stack_addr = stack_addr;
+ id.stack_addr_p = 1;
+ id.code_addr = code_addr;
+ id.code_addr_p = 1;
+ id.special_addr = special_addr;
+ id.special_addr_p = 1;
+ return id;
+}
+
struct frame_id
frame_id_build (CORE_ADDR stack_addr, CORE_ADDR code_addr)
{
- struct frame_id id;
+ struct frame_id id = null_frame_id;
id.stack_addr = stack_addr;
+ id.stack_addr_p = 1;
id.code_addr = code_addr;
+ id.code_addr_p = 1;
+ return id;
+}
+
+struct frame_id
+frame_id_build_wild (CORE_ADDR stack_addr)
+{
+ struct frame_id id = null_frame_id;
+ id.stack_addr = stack_addr;
+ id.stack_addr_p = 1;
return id;
}
frame_id_p (struct frame_id l)
{
int p;
- /* The .code can be NULL but the .stack cannot. */
- p = (l.stack_addr != 0);
+ /* The frame is valid iff it has a valid stack address. */
+ p = l.stack_addr_p;
if (frame_debug)
{
fprintf_unfiltered (gdb_stdlog, "{ frame_id_p (l=");
frame_id_eq (struct frame_id l, struct frame_id r)
{
int eq;
- if (l.stack_addr == 0 || r.stack_addr == 0)
- /* Like a NaN, if either ID is invalid, the result is false. */
+ if (!l.stack_addr_p || !r.stack_addr_p)
+ /* Like a NaN, if either ID is invalid, the result is false.
+ Note that a frame ID is invalid iff it is the null frame ID. */
eq = 0;
else if (l.stack_addr != r.stack_addr)
/* If .stack addresses are different, the frames are different. */
eq = 0;
- else if (l.code_addr == 0 || r.code_addr == 0)
- /* A zero code addr is a wild card, always succeed. */
+ else if (!l.code_addr_p || !r.code_addr_p)
+ /* An invalid code addr is a wild card, always succeed. */
+ eq = 1;
+ else if (l.code_addr != r.code_addr)
+ /* If .code addresses are different, the frames are different. */
+ eq = 0;
+ else if (!l.special_addr_p || !r.special_addr_p)
+ /* An invalid special addr is a wild card (or unused), always succeed. */
eq = 1;
- else if (l.code_addr == r.code_addr)
- /* The .stack and .code are identical, the ID's are identical. */
+ else if (l.special_addr == r.special_addr)
+ /* Frames are equal. */
eq = 1;
else
/* No luck. */
frame_id_inner (struct frame_id l, struct frame_id r)
{
int inner;
- if (l.stack_addr == 0 || r.stack_addr == 0)
+ if (!l.stack_addr_p || !r.stack_addr_p)
/* Like NaN, any operation involving an invalid ID always fails. */
inner = 0;
else
/* Only return non-zero when strictly inner than. Note that, per
comment in "frame.h", there is some fuzz here. Frameless
functions are not strictly inner than (same .stack but
- different .code). */
+ different .code and/or .special address). */
inner = INNER_THAN (l.stack_addr, r.stack_addr);
if (frame_debug)
{
if (frame_id_inner (id, this))
/* Gone to far. */
return NULL;
- /* Either, we're not yet gone far enough out along the frame
- chain (inner(this,id), or we're comparing frameless functions
+ /* Either we're not yet gone far enough out along the frame
+ chain (inner(this,id)), or we're comparing frameless functions
(same .base, different .func, no test available). Struggle
on until we've definitly gone to far. */
}
if (!this_frame->prev_pc.p)
{
CORE_ADDR pc;
- if (gdbarch_unwind_pc_p (current_gdbarch))
+ if (this_frame->unwind == NULL)
+ this_frame->unwind
+ = frame_unwind_find_by_frame (this_frame->next,
+ &this_frame->prologue_cache);
+ if (this_frame->unwind->prev_pc != NULL)
+ /* A per-frame unwinder, prefer it. */
+ pc = this_frame->unwind->prev_pc (this_frame->next,
+ &this_frame->prologue_cache);
+ else if (gdbarch_unwind_pc_p (current_gdbarch))
{
/* The right way. The `pure' way. The one true way. This
method depends solely on the register-unwind code to
different ways that a PC could be unwound. */
pc = gdbarch_unwind_pc (current_gdbarch, this_frame);
}
- else if (this_frame->level < 0)
- {
- /* FIXME: cagney/2003-03-06: Old code and and a sentinel
- frame. Do like was always done. Fetch the PC's value
- direct from the global registers array (via read_pc).
- This assumes that this frame belongs to the current
- global register cache. The assumption is dangerous. */
- pc = read_pc ();
- }
- else if (DEPRECATED_FRAME_SAVED_PC_P ())
- {
- /* FIXME: cagney/2003-03-06: Old code, but not a sentinel
- frame. Do like was always done. Note that this method,
- unlike unwind_pc(), tries to handle all the different
- frame cases directly. It fails. */
- pc = DEPRECATED_FRAME_SAVED_PC (this_frame);
- }
else
- internal_error (__FILE__, __LINE__, "No gdbarch_unwind_pc method");
+ internal_error (__FILE__, __LINE__, _("No unwind_pc method"));
this_frame->prev_pc.value = pc;
this_frame->prev_pc.p = 1;
if (frame_debug)
{
if (!fi->prev_func.p)
{
+ /* Make certain that this, and not the adjacent, function is
+ found. */
+ CORE_ADDR addr_in_block = frame_unwind_address_in_block (fi);
fi->prev_func.p = 1;
- fi->prev_func.addr = get_pc_function_start (frame_pc_unwind (fi));
+ fi->prev_func.addr = get_pc_function_start (addr_in_block);
if (frame_debug)
fprintf_unfiltered (gdb_stdlog,
"{ frame_func_unwind (fi=%d) -> 0x%s }\n",
}
static int
-do_frame_unwind_register (void *src, int regnum, void *buf)
+do_frame_register_read (void *src, int regnum, gdb_byte *buf)
{
- frame_unwind_register (src, regnum, buf);
+ frame_register_read (src, regnum, buf);
return 1;
}
+struct regcache *
+frame_save_as_regcache (struct frame_info *this_frame)
+{
+ struct regcache *regcache = regcache_xmalloc (current_gdbarch);
+ struct cleanup *cleanups = make_cleanup_regcache_xfree (regcache);
+ regcache_save (regcache, do_frame_register_read, this_frame);
+ discard_cleanups (cleanups);
+ return regcache;
+}
+
void
frame_pop (struct frame_info *this_frame)
{
- struct regcache *scratch_regcache;
- struct cleanup *cleanups;
+ /* Make a copy of all the register values unwound from this frame.
+ Save them in a scratch buffer so that there isn't a race between
+ trying to extract the old values from the current_regcache while
+ at the same time writing new values into that same cache. */
+ struct regcache *scratch
+ = frame_save_as_regcache (get_prev_frame_1 (this_frame));
+ struct cleanup *cleanups = make_cleanup_regcache_xfree (scratch);
+
+ /* FIXME: cagney/2003-03-16: It should be possible to tell the
+ target's register cache that it is about to be hit with a burst
+ register transfer and that the sequence of register writes should
+ be batched. The pair target_prepare_to_store() and
+ target_store_registers() kind of suggest this functionality.
+ Unfortunately, they don't implement it. Their lack of a formal
+ definition can lead to targets writing back bogus values
+ (arguably a bug in the target code mind). */
+ /* Now copy those saved registers into the current regcache.
+ Here, regcache_cpy() calls regcache_restore(). */
+ regcache_cpy (current_regcache, scratch);
+ do_cleanups (cleanups);
- if (DEPRECATED_POP_FRAME_P ())
- {
- /* A legacy architecture that has implemented a custom pop
- function. All new architectures should instead be using the
- generic code below. */
- DEPRECATED_POP_FRAME;
- }
- else
- {
- /* Make a copy of all the register values unwound from this
- frame. Save them in a scratch buffer so that there isn't a
- race betweening trying to extract the old values from the
- current_regcache while, at the same time writing new values
- into that same cache. */
- struct regcache *scratch = regcache_xmalloc (current_gdbarch);
- struct cleanup *cleanups = make_cleanup_regcache_xfree (scratch);
- regcache_save (scratch, do_frame_unwind_register, this_frame);
- /* FIXME: cagney/2003-03-16: It should be possible to tell the
- target's register cache that it is about to be hit with a
- burst register transfer and that the sequence of register
- writes should be batched. The pair target_prepare_to_store()
- and target_store_registers() kind of suggest this
- functionality. Unfortunatly, they don't implement it. Their
- lack of a formal definition can lead to targets writing back
- bogus values (arguably a bug in the target code mind). */
- /* Now copy those saved registers into the current regcache.
- Here, regcache_cpy() calls regcache_restore(). */
- regcache_cpy (current_regcache, scratch);
- do_cleanups (cleanups);
- }
/* We've made right mess of GDB's local state, just discard
everything. */
flush_cached_frames ();
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;
if (frame_debug)
{
- fprintf_unfiltered (gdb_stdlog,
- "{ frame_register_unwind (frame=%d,regnum=\"%s\",...) ",
- frame->level, frame_map_regnum_to_name (frame, regnum));
+ fprintf_unfiltered (gdb_stdlog, "\
+{ frame_register_unwind (frame=%d,regnum=%d(%s),...) ",
+ frame->level, regnum,
+ frame_map_regnum_to_name (frame, regnum));
}
/* Require all but BUFFERP to be valid. A NULL BUFFERP indicates
/* NOTE: cagney/2002-11-27: A program trying to unwind a NULL frame
is broken. There is always a frame. If there, for some reason,
- isn't, there is some pretty busted code as it should have
+ isn't a frame, there is some pretty busted code as it should have
detected the problem before calling here. */
gdb_assert (frame != NULL);
/* Find the unwinder. */
if (frame->unwind == NULL)
- {
- frame->unwind = frame_unwind_find_by_pc (current_gdbarch,
- get_frame_pc (frame));
- /* FIXME: cagney/2003-04-02: Rather than storing the frame's
- type in the frame, the unwinder's type should be returned
- directly. Unfortunatly, legacy code, called by
- legacy_get_prev_frame, explicitly set the frames type using
- the method deprecated_set_frame_type(). */
- gdb_assert (frame->unwind->type != UNKNOWN_FRAME);
- frame->type = frame->unwind->type;
- }
+ frame->unwind = frame_unwind_find_by_frame (frame->next,
+ &frame->prologue_cache);
/* Ask this frame to unwind its register. See comment in
- "frame-unwind.h" for why NEXT frame and this unwind cace are
+ "frame-unwind.h" for why NEXT frame and this unwind cache are
passed in. */
frame->unwind->prev_register (frame->next, &frame->prologue_cache, regnum,
optimizedp, lvalp, addrp, realnump, bufferp);
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. */
gdb_assert (realnump != NULL);
/* gdb_assert (bufferp != NULL); */
- /* Ulgh! Old code that, for lval_register, sets ADDRP to the offset
- of the register in the register cache. It should instead return
- the REGNUM corresponding to that register. Translate the . */
- if (DEPRECATED_GET_SAVED_REGISTER_P ())
- {
- DEPRECATED_GET_SAVED_REGISTER (bufferp, optimizedp, addrp, frame,
- regnum, lvalp);
- /* Compute the REALNUM if the caller wants it. */
- if (*lvalp == lval_register)
- {
- int regnum;
- for (regnum = 0; regnum < NUM_REGS + NUM_PSEUDO_REGS; regnum++)
- {
- if (*addrp == register_offset_hack (current_gdbarch, regnum))
- {
- *realnump = regnum;
- return;
- }
- }
- internal_error (__FILE__, __LINE__,
- "Failed to compute the register number corresponding"
- " to 0x%s", paddr_d (*addrp));
- }
- *realnump = -1;
- return;
- }
-
/* Obtain the register value by unwinding the register from the next
(more inner frame). */
gdb_assert (frame != NULL && frame->next != NULL);
}
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_VIRTUAL_SIZE (regnum));
+ return extract_signed_integer (buf, register_size (get_frame_arch (frame),
+ regnum));
}
LONGEST
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_VIRTUAL_SIZE (regnum));
+ return extract_unsigned_integer (buf, register_size (get_frame_arch (frame),
+ regnum));
}
ULONGEST
return frame_unwind_register_unsigned (frame->next, regnum);
}
-void
-frame_unwind_signed_register (struct frame_info *frame, int regnum,
- LONGEST *val)
-{
- char buf[MAX_REGISTER_SIZE];
- frame_unwind_register (frame, regnum, buf);
- (*val) = extract_signed_integer (buf, REGISTER_VIRTUAL_SIZE (regnum));
-}
-
void
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_VIRTUAL_SIZE (regnum));
+ (*val) = extract_unsigned_integer (buf,
+ register_size (get_frame_arch (frame),
+ regnum));
}
void
-frame_read_register (struct frame_info *frame, int regnum, void *buf)
-{
- gdb_assert (frame != NULL && frame->next != NULL);
- frame_unwind_register (frame->next, regnum, buf);
-}
-
-void
-frame_read_unsigned_register (struct frame_info *frame, int regnum,
- ULONGEST *val)
-{
- /* NOTE: cagney/2002-10-31: There is a bit of dogma here - there is
- always a frame. Both this, and the equivalent
- frame_read_signed_register() function, can only be called with a
- valid frame. If, for some reason, this function is called
- without a frame then the problem isn't here, but rather in the
- caller. It should of first created a frame and then passed that
- in. */
- /* NOTE: cagney/2002-10-31: As a side bar, keep in mind that the
- ``current_frame'' should not be treated as a special case. While
- ``get_next_frame (current_frame) == NULL'' currently holds, it
- should, as far as possible, not be relied upon. In the future,
- ``get_next_frame (current_frame)'' may instead simply return a
- normal frame object that simply always gets register values from
- the register cache. Consequently, frame code should try to avoid
- tests like ``if get_next_frame() == NULL'' and instead just rely
- on recursive frame calls (like the below code) when manipulating
- a frame chain. */
- gdb_assert (frame != NULL && frame->next != NULL);
- frame_unwind_unsigned_register (frame->next, regnum, val);
-}
-
-void
-frame_read_signed_register (struct frame_info *frame, int regnum,
- LONGEST *val)
-{
- /* See note above in frame_read_unsigned_register(). */
- gdb_assert (frame != NULL && frame->next != NULL);
- frame_unwind_signed_register (frame->next, regnum, val);
-}
-
-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;
CORE_ADDR addr;
frame_register (frame, regnum, &optim, &lval, &addr, &realnum, NULL);
if (optim)
- error ("Attempt to assign to a value that was optimized out.");
+ error (_("Attempt to assign to a value that was optimized out."));
switch (lval)
{
case lval_memory:
{
/* 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;
regcache_cooked_write (current_regcache, realnum, buf);
break;
default:
- error ("Attempt to assign to an unmodifiable value.");
+ error (_("Attempt to assign to an unmodifiable value."));
}
}
/* frame_register_read ()
Find and return the value of REGNUM for the specified stack frame.
- The number of bytes copied is REGISTER_RAW_SIZE (REGNUM).
+ The number of bytes copied is REGISTER_SIZE (REGNUM).
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;
int realnum;
frame_register (frame, regnum, &optimized, &lval, &addr, &realnum, myaddr);
- /* FIXME: cagney/2002-05-15: This test, is just bogus.
+ /* FIXME: cagney/2002-05-15: This test is just bogus.
It indicates that the target failed to supply a value for a
register because it was "not available" at this time. Problem
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
create_sentinel_frame (struct regcache *regcache)
{
struct frame_info *frame = FRAME_OBSTACK_ZALLOC (struct frame_info);
- frame->type = NORMAL_FRAME;
frame->level = -1;
/* Explicitly initialize the sentinel frame's cache. Provide it
with the underlying regcache. In the future additional
return data;
}
-CORE_ADDR *
-frame_saved_regs_zalloc (struct frame_info *fi)
-{
- fi->saved_regs = (CORE_ADDR *)
- frame_obstack_zalloc (SIZEOF_FRAME_SAVED_REGS);
- return fi->saved_regs;
-}
-
-CORE_ADDR *
-get_frame_saved_regs (struct frame_info *fi)
-{
- return fi->saved_regs;
-}
-
/* Return the innermost (currently executing) stack frame. This is
split into two functions. The function unwind_to_current_frame()
is wrapped in catch exceptions so that, even when the unwind of the
unwind_to_current_frame (struct ui_out *ui_out, void *args)
{
struct frame_info *frame = get_prev_frame (args);
- /* A sentinel frame can fail to unwind, eg, because it's PC value
+ /* A sentinel frame can fail to unwind, e.g., because its PC value
lands in somewhere like start. */
if (frame == NULL)
return 1;
explicitly checks that ``print $pc'' with no registers prints "No
registers". */
if (!target_has_registers)
- error ("No registers.");
+ error (_("No registers."));
if (!target_has_stack)
- error ("No stack.");
+ error (_("No stack."));
if (!target_has_memory)
- error ("No memory.");
+ error (_("No memory."));
if (current_frame == NULL)
{
struct frame_info *sentinel_frame =
create_sentinel_frame (current_regcache);
if (catch_exceptions (uiout, unwind_to_current_frame, sentinel_frame,
- NULL, RETURN_MASK_ERROR) != 0)
+ RETURN_MASK_ERROR) != 0)
{
/* Oops! Fake a current frame? Is this useful? It has a PC
of zero, for instance. */
struct frame_info *deprecated_selected_frame;
-/* Return the selected frame. Always non-null (unless there isn't an
+/* Return the selected frame. Always non-NULL (unless there isn't an
inferior sufficient for creating a frame) in which case an error is
thrown. */
struct frame_info *
-get_selected_frame (void)
+get_selected_frame (const char *message)
{
if (deprecated_selected_frame == NULL)
- /* Hey! Don't trust this. It should really be re-finding the
- last selected frame of the currently selected thread. This,
- though, is better than nothing. */
- select_frame (get_current_frame ());
+ {
+ if (message != NULL && (!target_has_registers
+ || !target_has_stack
+ || !target_has_memory))
+ error (("%s"), message);
+ /* Hey! Don't trust this. It should really be re-finding the
+ last selected frame of the currently selected thread. This,
+ though, is better than nothing. */
+ select_frame (get_current_frame ());
+ }
/* There is always a frame. */
gdb_assert (deprecated_selected_frame != NULL);
return deprecated_selected_frame;
}
+/* This is a variant of get_selected_frame() which can be called when
+ the inferior does not have a frame; in that case it will return
+ NULL instead of calling error(). */
+
+struct frame_info *
+deprecated_safe_get_selected_frame (void)
+{
+ if (!target_has_registers || !target_has_stack || !target_has_memory)
+ return NULL;
+ return get_selected_frame (NULL);
+}
+
/* Select frame FI (or NULL - to invalidate the current frame). */
void
select_frame (struct frame_info *fi)
{
- register struct symtab *s;
+ struct symtab *s;
deprecated_selected_frame = fi;
- /* NOTE: cagney/2002-05-04: FI can be NULL. This occures when the
+ /* NOTE: cagney/2002-05-04: FI can be NULL. This occurs when the
frame is being invalidated. */
- if (selected_frame_level_changed_hook)
- selected_frame_level_changed_hook (frame_relative_level (fi));
+ if (deprecated_selected_frame_level_changed_hook)
+ deprecated_selected_frame_level_changed_hook (frame_relative_level (fi));
/* FIXME: kseitz/2002-08-28: It would be nice to call
- selected_frame_level_changed_event right here, but due to limitations
+ selected_frame_level_changed_event() right here, but due to limitations
in the current interfaces, we would end up flooding UIs with events
- because select_frame is used extensively internally.
+ because select_frame() is used extensively internally.
Once we have frame-parameterized frame (and frame-related) commands,
the event notification can be moved here, since this function will only
- be called when the users selected frame is being changed. */
+ be called when the user's selected frame is being changed. */
/* Ensure that symbols for this frame are read in. Also, determine the
source language of this frame, and switch to it if desired. */
if (fi)
{
- s = find_pc_symtab (get_frame_pc (fi));
+ /* We retrieve the frame's symtab by using the frame PC. However
+ we cannot use the frame PC as-is, because it usually points to
+ the instruction following the "call", which is sometimes the
+ first instruction of another function. So we rely on
+ get_frame_address_in_block() which provides us with a PC which
+ is guaranteed to be inside the frame's code block. */
+ s = find_pc_symtab (get_frame_address_in_block (fi));
if (s
&& s->language != current_language->la_language
&& s->language != language_unknown
}
}
}
-
-/* Return the register saved in the simplistic ``saved_regs'' cache.
- If the value isn't here AND a value is needed, try the next inner
- most frame. */
-
-static void
-legacy_saved_regs_prev_register (struct frame_info *next_frame,
- void **this_prologue_cache,
- int regnum, int *optimizedp,
- enum lval_type *lvalp, CORE_ADDR *addrp,
- int *realnump, void *bufferp)
-{
- /* HACK: New code is passed the next frame and this cache.
- Unfortunatly, old code expects this frame. Since this is a
- backward compatibility hack, cheat by walking one level along the
- prologue chain to the frame the old code expects.
-
- Do not try this at home. Professional driver, closed course. */
- struct frame_info *frame = next_frame->prev;
- gdb_assert (frame != NULL);
-
- if (get_frame_saved_regs (frame) == NULL)
- {
- /* If nothing's initialized the saved regs, do it now. */
- gdb_assert (DEPRECATED_FRAME_INIT_SAVED_REGS_P ());
- DEPRECATED_FRAME_INIT_SAVED_REGS (frame);
- gdb_assert (get_frame_saved_regs (frame) != NULL);
- }
-
- if (get_frame_saved_regs (frame) != NULL
- && get_frame_saved_regs (frame)[regnum] != 0)
- {
- if (regnum == SP_REGNUM)
- {
- /* SP register treated specially. */
- *optimizedp = 0;
- *lvalp = not_lval;
- *addrp = 0;
- *realnump = -1;
- if (bufferp != NULL)
- /* NOTE: cagney/2003-05-09: In-lined store_address with
- it's body - store_unsigned_integer. */
- store_unsigned_integer (bufferp, REGISTER_RAW_SIZE (regnum),
- get_frame_saved_regs (frame)[regnum]);
- }
- else
- {
- /* Any other register is saved in memory, fetch it but cache
- a local copy of its value. */
- *optimizedp = 0;
- *lvalp = lval_memory;
- *addrp = get_frame_saved_regs (frame)[regnum];
- *realnump = -1;
- if (bufferp != NULL)
- {
-#if 1
- /* Save each register value, as it is read in, in a
- frame based cache. */
- void **regs = (*this_prologue_cache);
- if (regs == NULL)
- {
- int sizeof_cache = ((NUM_REGS + NUM_PSEUDO_REGS)
- * sizeof (void *));
- regs = frame_obstack_zalloc (sizeof_cache);
- (*this_prologue_cache) = regs;
- }
- if (regs[regnum] == NULL)
- {
- regs[regnum]
- = frame_obstack_zalloc (REGISTER_RAW_SIZE (regnum));
- read_memory (get_frame_saved_regs (frame)[regnum], regs[regnum],
- REGISTER_RAW_SIZE (regnum));
- }
- memcpy (bufferp, regs[regnum], REGISTER_RAW_SIZE (regnum));
-#else
- /* Read the value in from memory. */
- read_memory (get_frame_saved_regs (frame)[regnum], bufferp,
- REGISTER_RAW_SIZE (regnum));
-#endif
- }
- }
- return;
- }
-
- /* No luck. Assume this and the next frame have the same register
- value. Pass the unwind request down the frame chain to the next
- frame. Hopefully that frame will find the register's location. */
- frame_register_unwind (next_frame, regnum, optimizedp, lvalp, addrp,
- realnump, bufferp);
-}
-
-static void
-legacy_saved_regs_this_id (struct frame_info *next_frame,
- void **this_prologue_cache,
- struct frame_id *id)
-{
- /* legacy_get_prev_frame() always sets ->this_id.p, hence this is
- never needed. */
- internal_error (__FILE__, __LINE__, "legacy_saved_regs_this_id() called");
-}
-const struct frame_unwind legacy_saved_regs_unwinder = {
- /* Not really. It gets overridden by legacy_get_prev_frame. */
- UNKNOWN_FRAME,
- legacy_saved_regs_this_id,
- legacy_saved_regs_prev_register
-};
-const struct frame_unwind *legacy_saved_regs_unwind = &legacy_saved_regs_unwinder;
-
-
-/* Function: deprecated_generic_get_saved_register
- Find register number REGNUM relative to FRAME and put its (raw,
- target format) contents in *RAW_BUFFER.
-
- Set *OPTIMIZED if the variable was optimized out (and thus can't be
- fetched). Note that this is never set to anything other than zero
- in this implementation.
-
- Set *LVAL to lval_memory, lval_register, or not_lval, depending on
- whether the value was fetched from memory, from a register, or in a
- strange and non-modifiable way (e.g. a frame pointer which was
- calculated rather than fetched). We will use not_lval for values
- fetched from generic dummy frames.
-
- Set *ADDRP to the address, either in memory or as a REGISTER_BYTE
- offset into the registers array. If the value is stored in a dummy
- frame, set *ADDRP to zero.
-
- The argument RAW_BUFFER must point to aligned memory. */
-
-void
-deprecated_generic_get_saved_register (char *raw_buffer, int *optimized,
- CORE_ADDR *addrp,
- struct frame_info *frame, int regnum,
- enum lval_type *lval)
-{
- if (!target_has_registers)
- error ("No registers.");
-
- /* Normal systems don't optimize out things with register numbers. */
- if (optimized != NULL)
- *optimized = 0;
-
- if (addrp) /* default assumption: not found in memory */
- *addrp = 0;
-
- /* Note: since the current frame's registers could only have been
- saved by frames INTERIOR TO the current frame, we skip examining
- the current frame itself: otherwise, we would be getting the
- previous frame's registers which were saved by the current frame. */
-
- if (frame != NULL)
- {
- for (frame = get_next_frame (frame);
- frame_relative_level (frame) >= 0;
- frame = get_next_frame (frame))
- {
- if (get_frame_type (frame) == DUMMY_FRAME)
- {
- if (lval) /* found it in a CALL_DUMMY frame */
- *lval = not_lval;
- if (raw_buffer)
- /* FIXME: cagney/2002-06-26: This should be via the
- gdbarch_register_read() method so that it, on the
- fly, constructs either a raw or pseudo register
- from the raw register cache. */
- regcache_raw_read
- (deprecated_find_dummy_frame_regcache (get_frame_pc (frame),
- get_frame_base (frame)),
- regnum, raw_buffer);
- return;
- }
-
- DEPRECATED_FRAME_INIT_SAVED_REGS (frame);
- if (get_frame_saved_regs (frame) != NULL
- && get_frame_saved_regs (frame)[regnum] != 0)
- {
- if (lval) /* found it saved on the stack */
- *lval = lval_memory;
- if (regnum == SP_REGNUM)
- {
- if (raw_buffer) /* SP register treated specially */
- /* NOTE: cagney/2003-05-09: In-line store_address
- with it's body - store_unsigned_integer. */
- store_unsigned_integer (raw_buffer,
- REGISTER_RAW_SIZE (regnum),
- get_frame_saved_regs (frame)[regnum]);
- }
- else
- {
- if (addrp) /* any other register */
- *addrp = get_frame_saved_regs (frame)[regnum];
- if (raw_buffer)
- read_memory (get_frame_saved_regs (frame)[regnum], raw_buffer,
- REGISTER_RAW_SIZE (regnum));
- }
- return;
- }
- }
- }
-
- /* If we get thru the loop to this point, it means the register was
- not saved in any frame. Return the actual live-register value. */
-
- if (lval) /* found it in a live register */
- *lval = lval_register;
- if (addrp)
- *addrp = REGISTER_BYTE (regnum);
- if (raw_buffer)
- deprecated_read_register_gen (regnum, raw_buffer);
-}
-
-/* Determine the frame's type based on its PC. */
-
-static enum frame_type
-frame_type_from_pc (CORE_ADDR pc)
-{
- /* FIXME: cagney/2002-11-24: Can't yet directly call
- pc_in_dummy_frame() as some architectures don't set
- PC_IN_CALL_DUMMY() to generic_pc_in_call_dummy() (remember the
- latter is implemented by simply calling pc_in_dummy_frame). */
- if (DEPRECATED_USE_GENERIC_DUMMY_FRAMES
- && DEPRECATED_PC_IN_CALL_DUMMY (pc, 0, 0))
- return DUMMY_FRAME;
- else
- {
- char *name;
- find_pc_partial_function (pc, &name, NULL, NULL);
- if (PC_IN_SIGTRAMP (pc, name))
- return SIGTRAMP_FRAME;
- else
- return NORMAL_FRAME;
- }
-}
-
/* Create an arbitrary (i.e. address specified by user) or innermost frame.
Always returns a non-NULL value. */
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);
/* Select/initialize both the unwind function and the frame's type
based on the PC. */
- fi->unwind = frame_unwind_find_by_pc (current_gdbarch, pc);
- if (fi->unwind->type != UNKNOWN_FRAME)
- fi->type = fi->unwind->type;
- else
- fi->type = frame_type_from_pc (pc);
+ fi->unwind = frame_unwind_find_by_frame (fi->next, &fi->prologue_cache);
fi->this_id.p = 1;
deprecated_update_frame_base_hack (fi, addr);
deprecated_update_frame_pc_hack (fi, pc);
- if (DEPRECATED_INIT_EXTRA_FRAME_INFO_P ())
- DEPRECATED_INIT_EXTRA_FRAME_INFO (0, fi);
-
if (frame_debug)
{
fprintf_unfiltered (gdb_stdlog, "-> ");
return NULL;
}
-struct frame_info *
-deprecated_get_next_frame_hack (struct frame_info *this_frame)
+/* Observer for the target_changed event. */
+
+void
+frame_observer_target_changed (struct target_ops *target)
{
- return this_frame->next;
+ flush_cached_frames ();
}
/* Flush the entire frame cache. */
}
}
-/* Create the previous frame using the deprecated methods
- INIT_EXTRA_INFO, INIT_FRAME_PC and INIT_FRAME_PC_FIRST. */
+/* 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 struct frame_info *
-legacy_get_prev_frame (struct frame_info *this_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)
{
- CORE_ADDR address = 0;
- struct frame_info *prev;
- int fromleaf;
+ gdb_assert (this_frame == NULL || this_frame->level >= 0);
- /* Don't frame_debug print legacy_get_prev_frame() here, just
- confuses the output. */
+ while (this_frame != NULL)
+ {
+ frame_register_unwind (this_frame, regnum, optimizedp, lvalp,
+ addrp, realnump, NULL);
- /* Allocate the new frame.
+ if (*optimizedp)
+ break;
- There is no reason to worry about memory leaks, should the
- remainder of the function fail. The allocated memory will be
- quickly reclaimed when the frame cache is flushed, and the `we've
- been here before' check, in get_prev_frame will stop repeated
- memory allocation calls. */
- prev = FRAME_OBSTACK_ZALLOC (struct frame_info);
- prev->level = this_frame->level + 1;
-
- /* Do not completly wire it in to the frame chain. Some (bad) code
- in INIT_FRAME_EXTRA_INFO tries to look along frame->prev to pull
- some fancy tricks (of course such code is, by definition,
- recursive).
-
- On the other hand, methods, such as get_frame_pc() and
- get_frame_base() rely on being able to walk along the frame
- chain. Make certain that at least they work by providing that
- link. Of course things manipulating prev can't go back. */
- prev->next = this_frame;
-
- /* NOTE: cagney/2002-11-18: Should have been correctly setting the
- frame's type here, before anything else, and not last, at the
- bottom of this function. The various
- DEPRECATED_INIT_EXTRA_FRAME_INFO, DEPRECATED_INIT_FRAME_PC,
- DEPRECATED_INIT_FRAME_PC_FIRST and
- DEPRECATED_FRAME_INIT_SAVED_REGS methods are full of work-arounds
- that handle the frame not being correctly set from the start.
- Unfortunatly those same work-arounds rely on the type defaulting
- to NORMAL_FRAME. Ulgh! The new frame code does not have this
- problem. */
- prev->type = UNKNOWN_FRAME;
-
- /* A legacy frame's ID is always computed here. Mark it as valid. */
- prev->this_id.p = 1;
-
- /* Handle sentinel frame unwind as a special case. */
- if (this_frame->level < 0)
- {
- /* Try to unwind the PC. If that doesn't work, assume we've reached
- the oldest frame and simply return. Is there a better sentinal
- value? The unwound PC value is then used to initialize the new
- previous frame's type.
-
- Note that the pc-unwind is intentionally performed before the
- frame chain. This is ok since, for old targets, both
- frame_pc_unwind (nee, DEPRECATED_FRAME_SAVED_PC) and
- DEPRECATED_FRAME_CHAIN()) assume THIS_FRAME's data structures
- have already been initialized (using
- DEPRECATED_INIT_EXTRA_FRAME_INFO) and hence the call order
- doesn't matter.
-
- By unwinding the PC first, it becomes possible to, in the case of
- a dummy frame, avoid also unwinding the frame ID. This is
- because (well ignoring the PPC) a dummy frame can be located
- using THIS_FRAME's frame ID. */
-
- deprecated_update_frame_pc_hack (prev, frame_pc_unwind (this_frame));
- if (get_frame_pc (prev) == 0)
- {
- /* The allocated PREV_FRAME will be reclaimed when the frame
- obstack is next purged. */
- if (frame_debug)
- {
- fprintf_unfiltered (gdb_stdlog, "-> ");
- fprint_frame (gdb_stdlog, NULL);
- fprintf_unfiltered (gdb_stdlog,
- " // unwound legacy PC zero }\n");
- }
- return NULL;
- }
+ if (*lvalp != lval_register)
+ break;
- /* Set the unwind functions based on that identified PC. Ditto
- for the "type" but strongly prefer the unwinder's frame type. */
- prev->unwind = frame_unwind_find_by_pc (current_gdbarch,
- get_frame_pc (prev));
- if (prev->unwind->type == UNKNOWN_FRAME)
- prev->type = frame_type_from_pc (get_frame_pc (prev));
- else
- prev->type = prev->unwind->type;
+ regnum = *realnump;
+ this_frame = get_next_frame (this_frame);
+ }
+}
- /* Find the prev's frame's ID. */
- if (prev->type == DUMMY_FRAME
- && gdbarch_unwind_dummy_id_p (current_gdbarch))
- {
- /* When unwinding a normal frame, the stack structure is
- determined by analyzing the frame's function's code (be
- it using brute force prologue analysis, or the dwarf2
- CFI). In the case of a dummy frame, that simply isn't
- possible. The The PC is either the program entry point,
- or some random address on the stack. Trying to use that
- PC to apply standard frame ID unwind techniques is just
- asking for trouble. */
- /* Use an architecture specific method to extract the prev's
- dummy ID from the next frame. Note that this method uses
- frame_register_unwind to obtain the register values
- needed to determine the dummy frame's ID. */
- prev->this_id.value = gdbarch_unwind_dummy_id (current_gdbarch,
- this_frame);
- }
- else
- {
- /* We're unwinding a sentinel frame, the PC of which is
- pointing at a stack dummy. Fake up the dummy frame's ID
- using the same sequence as is found a traditional
- unwinder. Once all architectures supply the
- unwind_dummy_id method, this code can go away. */
- prev->this_id.value = frame_id_build (deprecated_read_fp (),
- read_pc ());
- }
+/* Return a "struct frame_info" corresponding to the frame that called
+ THIS_FRAME. Returns NULL if there is no such frame.
- /* Check that the unwound ID is valid. */
- if (!frame_id_p (prev->this_id.value))
- {
- if (frame_debug)
- {
- fprintf_unfiltered (gdb_stdlog, "-> ");
- fprint_frame (gdb_stdlog, NULL);
- fprintf_unfiltered (gdb_stdlog,
- " // unwound legacy ID invalid }\n");
- }
- return NULL;
- }
+ Unlike get_prev_frame, this function always tries to unwind the
+ frame. */
- /* Check that the new frame isn't inner to (younger, below,
- next) the old frame. If that happens the frame unwind is
- going backwards. */
- /* FIXME: cagney/2003-02-25: Ignore the sentinel frame since
- that doesn't have a valid frame ID. Should instead set the
- sentinel frame's frame ID to a `sentinel'. Leave it until
- after the switch to storing the frame ID, instead of the
- frame base, in the frame object. */
-
- /* Link it in. */
- this_frame->prev = prev;
-
- /* FIXME: cagney/2002-01-19: This call will go away. Instead of
- initializing extra info, all frames will use the frame_cache
- (passed to the unwind functions) to store additional frame
- info. Unfortunatly legacy targets can't use
- legacy_get_prev_frame() to unwind the sentinel frame and,
- consequently, are forced to take this code path and rely on
- the below call to DEPRECATED_INIT_EXTRA_FRAME_INFO to
- initialize the inner-most frame. */
- if (DEPRECATED_INIT_EXTRA_FRAME_INFO_P ())
- {
- DEPRECATED_INIT_EXTRA_FRAME_INFO (0, prev);
- }
+static struct frame_info *
+get_prev_frame_1 (struct frame_info *this_frame)
+{
+ struct frame_info *prev_frame;
+ struct frame_id this_id;
- if (prev->type == NORMAL_FRAME)
- prev->this_id.value.code_addr
- = get_pc_function_start (prev->this_id.value.code_addr);
+ gdb_assert (this_frame != NULL);
- if (frame_debug)
- {
- fprintf_unfiltered (gdb_stdlog, "-> ");
- fprint_frame (gdb_stdlog, prev);
- fprintf_unfiltered (gdb_stdlog, " } // legacy innermost frame\n");
- }
- return prev;
- }
-
- /* This code only works on normal frames. A sentinel frame, where
- the level is -1, should never reach this code. */
- gdb_assert (this_frame->level >= 0);
-
- /* On some machines it is possible to call a function without
- setting up a stack frame for it. On these machines, we
- define this macro to take two args; a frameinfo pointer
- identifying a frame and a variable to set or clear if it is
- or isn't leafless. */
-
- /* Still don't want to worry about this except on the innermost
- frame. This macro will set FROMLEAF if THIS_FRAME is a frameless
- function invocation. */
- if (this_frame->level == 0)
- /* FIXME: 2002-11-09: Frameless functions can occure anywhere in
- the frame chain, not just the inner most frame! The generic,
- per-architecture, frame code should handle this and the below
- should simply be removed. */
- fromleaf = FRAMELESS_FUNCTION_INVOCATION (this_frame);
- else
- fromleaf = 0;
-
- if (fromleaf)
- /* A frameless inner-most frame. The `FP' (which isn't an
- architecture frame-pointer register!) of the caller is the same
- as the callee. */
- /* FIXME: 2002-11-09: There isn't any reason to special case this
- edge condition. Instead the per-architecture code should hande
- it locally. */
- /* FIXME: cagney/2003-06-16: This returns the inner most stack
- address for the previous frame, that, however, is wrong. It
- should be the inner most stack address for the previous to
- previous frame. This is because it is the previous to previous
- frame's innermost stack address that is constant through out
- the lifetime of the previous frame (trust me :-). */
- address = get_frame_base (this_frame);
- else
+ if (frame_debug)
{
- /* Two macros defined in tm.h specify the machine-dependent
- actions to be performed here.
-
- First, get the frame's chain-pointer.
-
- If that is zero, the frame is the outermost frame or a leaf
- called by the outermost frame. This means that if start
- calls main without a frame, we'll return 0 (which is fine
- anyway).
-
- Nope; there's a problem. This also returns when the current
- routine is a leaf of main. This is unacceptable. We move
- this to after the ffi test; I'd rather have backtraces from
- start go curfluy than have an abort called from main not show
- main. */
- if (DEPRECATED_FRAME_CHAIN_P ())
- address = DEPRECATED_FRAME_CHAIN (this_frame);
+ fprintf_unfiltered (gdb_stdlog, "{ get_prev_frame_1 (this_frame=");
+ if (this_frame != NULL)
+ fprintf_unfiltered (gdb_stdlog, "%d", this_frame->level);
else
- {
- /* Someone is part way through coverting an old architecture
- to the new frame code. Implement FRAME_CHAIN the way the
- new frame will. */
- /* Find PREV frame's unwinder. */
- prev->unwind = frame_unwind_find_by_pc (current_gdbarch,
- frame_pc_unwind (this_frame));
- /* FIXME: cagney/2003-04-02: Rather than storing the frame's
- type in the frame, the unwinder's type should be returned
- directly. Unfortunatly, legacy code, called by
- legacy_get_prev_frame, explicitly set the frames type
- using the method deprecated_set_frame_type(). */
- prev->type = prev->unwind->type;
- /* Find PREV frame's ID. */
- prev->unwind->this_id (this_frame,
- &prev->prologue_cache,
- &prev->this_id.value);
- prev->this_id.p = 1;
- address = prev->this_id.value.stack_addr;
- }
+ fprintf_unfiltered (gdb_stdlog, "<NULL>");
+ fprintf_unfiltered (gdb_stdlog, ") ");
+ }
- if (!legacy_frame_chain_valid (address, this_frame))
+ /* Only try to do the unwind once. */
+ if (this_frame->prev_p)
+ {
+ if (frame_debug)
{
- if (frame_debug)
- {
- fprintf_unfiltered (gdb_stdlog, "-> ");
- fprint_frame (gdb_stdlog, NULL);
- fprintf_unfiltered (gdb_stdlog,
- " // legacy frame chain invalid }\n");
- }
- return NULL;
+ fprintf_unfiltered (gdb_stdlog, "-> ");
+ fprint_frame (gdb_stdlog, this_frame->prev);
+ fprintf_unfiltered (gdb_stdlog, " // cached \n");
}
+ return this_frame->prev;
}
- if (address == 0)
+ 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
+ the sentinel frame. */
+ this_id = get_frame_id (this_frame);
+ if (this_frame->level >= 0 && !frame_id_p (this_id))
{
if (frame_debug)
{
fprintf_unfiltered (gdb_stdlog, "-> ");
fprint_frame (gdb_stdlog, NULL);
- fprintf_unfiltered (gdb_stdlog,
- " // legacy frame chain NULL }\n");
+ fprintf_unfiltered (gdb_stdlog, " // this ID is NULL }\n");
}
+ this_frame->stop_reason = UNWIND_NULL_ID;
return NULL;
}
- /* Link in the already allocated prev frame. */
- this_frame->prev = prev;
- deprecated_update_frame_base_hack (prev, address);
-
- /* This change should not be needed, FIXME! We should determine
- whether any targets *need* DEPRECATED_INIT_FRAME_PC to happen
- after DEPRECATED_INIT_EXTRA_FRAME_INFO and come up with a simple
- way to express what goes on here.
-
- DEPRECATED_INIT_EXTRA_FRAME_INFO is called from two places:
- create_new_frame (where the PC is already set up) and here (where
- it isn't). DEPRECATED_INIT_FRAME_PC is only called from here,
- always after DEPRECATED_INIT_EXTRA_FRAME_INFO.
-
- The catch is the MIPS, where DEPRECATED_INIT_EXTRA_FRAME_INFO
- requires the PC value (which hasn't been set yet). Some other
- machines appear to require DEPRECATED_INIT_EXTRA_FRAME_INFO
- before they can do DEPRECATED_INIT_FRAME_PC. Phoo.
-
- We shouldn't need DEPRECATED_INIT_FRAME_PC_FIRST to add more
- complication to an already overcomplicated part of GDB.
- gnu@cygnus.com, 15Sep92.
-
- Assuming that some machines need DEPRECATED_INIT_FRAME_PC after
- DEPRECATED_INIT_EXTRA_FRAME_INFO, one possible scheme:
-
- SETUP_INNERMOST_FRAME(): Default version is just create_new_frame
- (deprecated_read_fp ()), read_pc ()). Machines with extra frame
- info would do that (or the local equivalent) and then set the
- extra fields.
-
- SETUP_ARBITRARY_FRAME(argc, argv): Only change here is that
- create_new_frame would no longer init extra frame info;
- SETUP_ARBITRARY_FRAME would have to do that.
-
- INIT_PREV_FRAME(fromleaf, prev) Replace
- DEPRECATED_INIT_EXTRA_FRAME_INFO and DEPRECATED_INIT_FRAME_PC.
- This should also return a flag saying whether to keep the new
- frame, or whether to discard it, because on some machines (e.g.
- mips) it is really awkward to have DEPRECATED_FRAME_CHAIN_VALID
- called BEFORE DEPRECATED_INIT_EXTRA_FRAME_INFO (there is no good
- way to get information deduced in DEPRECATED_FRAME_CHAIN_VALID
- into the extra fields of the new frame). std_frame_pc(fromleaf,
- prev)
-
- This is the default setting for INIT_PREV_FRAME. It just does
- what the default DEPRECATED_INIT_FRAME_PC does. Some machines
- will call it from INIT_PREV_FRAME (either at the beginning, the
- end, or in the middle). Some machines won't use it.
-
- kingdon@cygnus.com, 13Apr93, 31Jan94, 14Dec94. */
-
- /* NOTE: cagney/2002-11-09: Just ignore the above! There is no
- reason for things to be this complicated.
-
- The trick is to assume that there is always a frame. Instead of
- special casing the inner-most frame, create fake frame
- (containing the hardware registers) that is inner to the
- user-visible inner-most frame (...) and then unwind from that.
- That way architecture code can use use the standard
- frame_XX_unwind() functions and not differentiate between the
- inner most and any other case.
-
- Since there is always a frame to unwind from, there is always
- somewhere (THIS_FRAME) to store all the info needed to construct
- a new (previous) frame without having to first create it. This
- means that the convolution below - needing to carefully order a
- frame's initialization - isn't needed.
-
- The irony here though, is that DEPRECATED_FRAME_CHAIN(), at least
- for a more up-to-date architecture, always calls
- FRAME_SAVED_PC(), and FRAME_SAVED_PC() computes the PC but
- without first needing the frame! Instead of the convolution
- below, we could have simply called FRAME_SAVED_PC() and been done
- with it! Note that FRAME_SAVED_PC() is being superseed by
- frame_pc_unwind() and that function does have somewhere to cache
- that PC value. */
-
- if (DEPRECATED_INIT_FRAME_PC_FIRST_P ())
- deprecated_update_frame_pc_hack (prev,
- DEPRECATED_INIT_FRAME_PC_FIRST (fromleaf,
- prev));
-
- if (DEPRECATED_INIT_EXTRA_FRAME_INFO_P ())
- DEPRECATED_INIT_EXTRA_FRAME_INFO (fromleaf, prev);
-
- /* This entry is in the frame queue now, which is good since
- FRAME_SAVED_PC may use that queue to figure out its value (see
- tm-sparc.h). We want the pc saved in the inferior frame. */
- if (DEPRECATED_INIT_FRAME_PC_P ())
- deprecated_update_frame_pc_hack (prev,
- DEPRECATED_INIT_FRAME_PC (fromleaf,
- prev));
-
- /* If ->frame and ->pc are unchanged, we are in the process of
- getting ourselves into an infinite backtrace. Some architectures
- check this in DEPRECATED_FRAME_CHAIN or thereabouts, but it seems
- like there is no reason this can't be an architecture-independent
- check. */
- if (get_frame_base (prev) == get_frame_base (this_frame)
- && get_frame_pc (prev) == get_frame_pc (this_frame))
+ /* Check that this frame's ID isn't inner to (younger, below, next)
+ the next frame. This happens when a frame unwind goes backwards.
+ Exclude signal trampolines (due to sigaltstack the frame ID can
+ go backwards) and sentinel frames (the test is meaningless). */
+ if (this_frame->next->level >= 0
+ && this_frame->next->unwind->type != SIGTRAMP_FRAME
+ && frame_id_inner (this_id, get_frame_id (this_frame->next)))
{
- this_frame->prev = NULL;
- obstack_free (&frame_cache_obstack, prev);
if (frame_debug)
{
fprintf_unfiltered (gdb_stdlog, "-> ");
fprint_frame (gdb_stdlog, NULL);
- fprintf_unfiltered (gdb_stdlog,
- " // legacy this.id == prev.id }\n");
+ fprintf_unfiltered (gdb_stdlog, " // this frame ID is inner }\n");
}
+ this_frame->stop_reason = UNWIND_INNER_ID;
return NULL;
}
- /* Initialize the code used to unwind the frame PREV based on the PC
- (and probably other architectural information). The PC lets you
- check things like the debug info at that point (dwarf2cfi?) and
- use that to decide how the frame should be unwound.
-
- If there isn't a FRAME_CHAIN, the code above will have already
- done this. */
- if (prev->unwind == NULL)
- prev->unwind = frame_unwind_find_by_pc (current_gdbarch,
- get_frame_pc (prev));
-
- /* If the unwinder provides a frame type, use it. Otherwize
- continue on to that heuristic mess. */
- if (prev->unwind->type != UNKNOWN_FRAME)
+ /* 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)))
{
- prev->type = prev->unwind->type;
- if (prev->type == NORMAL_FRAME)
- /* FIXME: cagney/2003-06-16: would get_frame_pc() be better? */
- prev->this_id.value.code_addr
- = get_pc_function_start (prev->this_id.value.code_addr);
if (frame_debug)
{
fprintf_unfiltered (gdb_stdlog, "-> ");
- fprint_frame (gdb_stdlog, prev);
- fprintf_unfiltered (gdb_stdlog, " } // legacy with unwound type\n");
+ fprint_frame (gdb_stdlog, NULL);
+ fprintf_unfiltered (gdb_stdlog, " // this frame has same ID }\n");
}
- return prev;
+ this_frame->stop_reason = UNWIND_SAME_ID;
+ return NULL;
}
- /* NOTE: cagney/2002-11-18: The code segments, found in
- create_new_frame and get_prev_frame(), that initializes the
- frames type is subtly different. The latter only updates ->type
- when it encounters a SIGTRAMP_FRAME or DUMMY_FRAME. This stops
- get_prev_frame() overriding the frame's type when the INIT code
- has previously set it. This is really somewhat bogus. The
- initialization, as seen in create_new_frame(), should occur
- before the INIT function has been called. */
- if (DEPRECATED_USE_GENERIC_DUMMY_FRAMES
- && (DEPRECATED_PC_IN_CALL_DUMMY_P ()
- ? DEPRECATED_PC_IN_CALL_DUMMY (get_frame_pc (prev), 0, 0)
- : pc_in_dummy_frame (get_frame_pc (prev))))
- prev->type = DUMMY_FRAME;
- else
+ /* 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)
{
- /* FIXME: cagney/2002-11-10: This should be moved to before the
- INIT code above so that the INIT code knows what the frame's
- type is (in fact, for a [generic] dummy-frame, the type can
- be set and then the entire initialization can be skipped.
- Unforunatly, its the INIT code that sets the PC (Hmm, catch
- 22). */
- char *name;
- find_pc_partial_function (get_frame_pc (prev), &name, NULL, NULL);
- if (PC_IN_SIGTRAMP (get_frame_pc (prev), name))
- prev->type = SIGTRAMP_FRAME;
- /* FIXME: cagney/2002-11-11: Leave prev->type alone. Some
- architectures are forcing the frame's type in INIT so we
- don't want to override it here. Remember, NORMAL_FRAME == 0,
- so it all works (just :-/). Once this initialization is
- moved to the start of this function, all this nastness will
- go away. */
+ 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;
+ }
}
- if (prev->type == NORMAL_FRAME)
- prev->this_id.value.code_addr
- = get_pc_function_start (prev->this_id.value.code_addr);
+ /* 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
+ frame->next to pull some fancy tricks (of course such code is, by
+ definition, recursive). Try to prevent it.
+
+ There is no reason to worry about memory leaks, should the
+ remainder of the function fail. The allocated memory will be
+ quickly reclaimed when the frame cache is flushed, and the `we've
+ been here before' check above will stop repeated memory
+ allocation calls. */
+ prev_frame = FRAME_OBSTACK_ZALLOC (struct frame_info);
+ prev_frame->level = this_frame->level + 1;
+
+ /* Don't yet compute ->unwind (and hence ->type). It is computed
+ on-demand in get_frame_type, frame_register_unwind, and
+ get_frame_id. */
+
+ /* Don't yet compute the frame's ID. It is computed on-demand by
+ get_frame_id(). */
+
+ /* The unwound frame ID is validate at the start of this function,
+ as part of the logic to decide if that frame should be further
+ unwound, and not here while the prev frame is being created.
+ Doing this makes it possible for the user to examine a frame that
+ has an invalid frame ID.
+
+ Some very old VAX code noted: [...] For the sake of argument,
+ suppose that the stack is somewhat trashed (which is one reason
+ that "info frame" exists). So, return 0 (indicating we don't
+ know the address of the arglist) if we don't know what frame this
+ frame calls. */
+
+ /* Link it in. */
+ this_frame->prev = prev_frame;
+ prev_frame->next = this_frame;
if (frame_debug)
{
fprintf_unfiltered (gdb_stdlog, "-> ");
- fprint_frame (gdb_stdlog, prev);
- fprintf_unfiltered (gdb_stdlog, " } // legacy with confused type\n");
+ fprint_frame (gdb_stdlog, prev_frame);
+ fprintf_unfiltered (gdb_stdlog, " }\n");
}
- return prev;
+ return prev_frame;
}
-/* Return a structure containing various interesting information
- about the frame that called THIS_FRAME. Returns NULL
- if there is no such frame. */
+/* Debug routine to print a NULL frame being returned. */
-struct frame_info *
-get_prev_frame (struct frame_info *this_frame)
+static void
+frame_debug_got_null_frame (struct ui_file *file,
+ struct frame_info *this_frame,
+ const char *reason)
{
- struct frame_info *prev_frame;
-
if (frame_debug)
{
fprintf_unfiltered (gdb_stdlog, "{ get_prev_frame (this_frame=");
fprintf_unfiltered (gdb_stdlog, "%d", this_frame->level);
else
fprintf_unfiltered (gdb_stdlog, "<NULL>");
- fprintf_unfiltered (gdb_stdlog, ") ");
+ fprintf_unfiltered (gdb_stdlog, ") -> // %s}\n", reason);
}
+}
+
+/* Is this (non-sentinel) frame in the "main"() function? */
+
+static int
+inside_main_func (struct frame_info *this_frame)
+{
+ struct minimal_symbol *msymbol;
+ CORE_ADDR maddr;
+
+ if (symfile_objfile == 0)
+ return 0;
+ msymbol = lookup_minimal_symbol (main_name (), NULL, symfile_objfile);
+ if (msymbol == NULL)
+ return 0;
+ /* Make certain that the code, and not descriptor, address is
+ returned. */
+ maddr = gdbarch_convert_from_func_ptr_addr (current_gdbarch,
+ SYMBOL_VALUE_ADDRESS (msymbol),
+ ¤t_target);
+ return maddr == get_frame_func (this_frame);
+}
+
+/* Test whether THIS_FRAME is inside the process entry point function. */
+
+static int
+inside_entry_func (struct frame_info *this_frame)
+{
+ return (get_frame_func (this_frame) == entry_point_address ());
+}
+
+/* Return a structure containing various interesting information about
+ the frame that called THIS_FRAME. Returns NULL if there is entier
+ no such frame or the frame fails any of a set of target-independent
+ condition that should terminate the frame chain (e.g., as unwinding
+ past main()).
+
+ This function should not contain target-dependent tests, such as
+ checking whether the program-counter is zero. */
+
+struct frame_info *
+get_prev_frame (struct frame_info *this_frame)
+{
+ struct frame_info *prev_frame;
/* Return the inner-most frame, when the caller passes in NULL. */
/* NOTE: cagney/2002-11-09: Not sure how this would happen. The
while (1) { frame = get_prev_frame (frame); .... }. Ulgh! Why
it couldn't be written better, I don't know.
- NOTE: cagney/2003-01-11: I suspect what is happening is
+ NOTE: cagney/2003-01-11: I suspect what is happening in
block_innermost_frame() is, when the target has no state
- (registers, memory, ...), still calling this function. The
+ (registers, memory, ...), it is still calling this function. The
assumption being that this function will return NULL indicating
that a frame isn't possible, rather than checking that the target
has state and then calling get_current_frame() and
Per the above, this code shouldn't even be called with a NULL
THIS_FRAME. */
+ frame_debug_got_null_frame (gdb_stdlog, this_frame, "this_frame NULL");
return current_frame;
}
get_current_frame(). */
gdb_assert (this_frame != NULL);
+ /* tausq/2004-12-07: Dummy frames are skipped because it doesn't make much
+ sense to stop unwinding at a dummy frame. One place where a dummy
+ frame may have an address "inside_main_func" is on HPUX. On HPUX, the
+ pcsqh register (space register for the instruction at the head of the
+ instruction queue) cannot be written directly; the only way to set it
+ is to branch to code that is in the target space. In order to implement
+ frame dummies on HPUX, the called function is made to jump back to where
+ the inferior was when the user function was called. If gdb was inside
+ the main function when we created the dummy frame, the dummy frame will
+ point inside the main function. */
if (this_frame->level >= 0
- && !backtrace_below_main
- && inside_main_func (get_frame_pc (this_frame)))
- /* Don't unwind past main(), bug always unwind the sentinel frame.
- Note, this is done _before_ the frame has been marked as
- previously unwound. That way if the user later decides to
- allow unwinds past main(), that just happens. */
+ && get_frame_type (this_frame) != DUMMY_FRAME
+ && !backtrace_past_main
+ && inside_main_func (this_frame))
+ /* Don't unwind past main(). Note, this is done _before_ the
+ frame has been marked as previously unwound. That way if the
+ user later decides to enable unwinds past main(), that will
+ automatically happen. */
{
- if (frame_debug)
- fprintf_unfiltered (gdb_stdlog, "-> NULL // inside main func }\n");
+ frame_debug_got_null_frame (gdb_stdlog, this_frame, "inside main func");
return NULL;
}
- /* Only try to do the unwind once. */
- if (this_frame->prev_p)
- {
- if (frame_debug)
- {
- fprintf_unfiltered (gdb_stdlog, "-> ");
- fprint_frame (gdb_stdlog, this_frame->prev);
- fprintf_unfiltered (gdb_stdlog, " // cached \n");
- }
- return this_frame->prev;
- }
- this_frame->prev_p = 1;
-
-#if 0
- /* If we're inside the entry file, it isn't valid. Don't apply this
- test to a dummy frame - dummy frame PC's typically land in the
- entry file. Don't apply this test to the sentinel frame.
- Sentinel frames should always be allowed to unwind. */
- /* NOTE: drow/2002-12-25: should there be a way to disable this
- check? It assumes a single small entry file, and the way some
- debug readers (e.g. dbxread) figure out which object is the
- entry file is somewhat hokey. */
- /* NOTE: cagney/2003-01-10: If there is a way of disabling this test
- then it should probably be moved to before the ->prev_p test,
- above. */
- /* NOTE: vinschen/2003-04-01: Disabled. It turns out that the call to
- inside_entry_file destroys a meaningful backtrace under some
- conditions. E. g. the backtrace tests in the asm-source testcase
- are broken for some targets. In this test the functions are all
- implemented as part of one file and the testcase is not necessarily
- linked with a start file (depending on the target). What happens is,
- that the first frame is printed normaly and following frames are
- treated as being inside the enttry file then. This way, only the
- #0 frame is printed in the backtrace output. */
- if (this_frame->type != DUMMY_FRAME && this_frame->level >= 0
- && inside_entry_file (get_frame_pc (this_frame)))
+ /* 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)
{
- if (frame_debug)
- {
- fprintf_unfiltered (gdb_stdlog, "-> ");
- fprint_frame (gdb_stdlog, NULL);
- fprintf_unfiltered (gdb_stdlog, " // inside entry file }\n");
- }
+ frame_debug_got_null_frame (gdb_stdlog, this_frame,
+ "backtrace limit exceeded");
return NULL;
}
-#endif
/* If we're already inside the entry function for the main objfile,
then it isn't valid. Don't apply this test to a dummy frame -
- dummy frame PC's typically land in the entry func. Don't apply
+ dummy frame PCs typically land in the entry func. Don't apply
this test to the sentinel frame. Sentinel frames should always
be allowed to unwind. */
- /* NOTE: cagney/2003-02-25: Don't enable until someone has found
- hard evidence that this is needed. */
- if (0
- && this_frame->type != DUMMY_FRAME && this_frame->level >= 0
- && inside_entry_func (get_frame_pc (this_frame)))
- {
- if (frame_debug)
- {
- fprintf_unfiltered (gdb_stdlog, "-> ");
- fprint_frame (gdb_stdlog, NULL);
- fprintf_unfiltered (gdb_stdlog, "// inside entry func }\n");
- }
- return NULL;
- }
-
- /* If any of the old frame initialization methods are around, use
- the legacy get_prev_frame method. */
- if (legacy_frame_p (current_gdbarch))
- {
- prev_frame = legacy_get_prev_frame (this_frame);
- return prev_frame;
- }
-
- /* 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
- the sentinel frame. */
- if (this_frame->level >= 0 && !frame_id_p (get_frame_id (this_frame)))
+ /* NOTE: cagney/2003-07-07: Fixed a bug in inside_main_func() -
+ wasn't checking for "main" in the minimal symbols. With that
+ fixed asm-source tests now stop in "main" instead of halting the
+ backtrace in weird and wonderful ways somewhere inside the entry
+ file. Suspect that tests for inside the entry file/func were
+ added to work around that (now fixed) case. */
+ /* NOTE: cagney/2003-07-15: danielj (if I'm reading it right)
+ suggested having the inside_entry_func test use the
+ inside_main_func() msymbol trick (along with entry_point_address()
+ I guess) to determine the address range of the start function.
+ That should provide a far better stopper than the current
+ heuristics. */
+ /* NOTE: tausq/2004-10-09: this is needed if, for example, the compiler
+ applied tail-call optimizations to main so that a function called
+ from main returns directly to the caller of main. Since we don't
+ stop at main, we should at least stop at the entry point of the
+ application. */
+ if (!backtrace_past_entry
+ && get_frame_type (this_frame) != DUMMY_FRAME && this_frame->level >= 0
+ && inside_entry_func (this_frame))
{
- if (frame_debug)
- {
- fprintf_unfiltered (gdb_stdlog, "-> ");
- fprint_frame (gdb_stdlog, NULL);
- fprintf_unfiltered (gdb_stdlog, " // this ID is NULL }\n");
- }
+ frame_debug_got_null_frame (gdb_stdlog, this_frame, "inside entry func");
return NULL;
}
- /* Check that this frame's ID isn't inner to (younger, below, next)
- the next frame. This happens when frame unwind goes backwards.
- Since the sentinel frame isn't valid, don't apply this if this
- frame is entier the inner-most or sentinel frame. */
+ /* Assume that the only way to get a zero PC is through something
+ like a SIGSEGV or a dummy frame, and hence that NORMAL frames
+ will never unwind a zero PC. */
if (this_frame->level > 0
- && frame_id_inner (get_frame_id (this_frame),
- get_frame_id (this_frame->next)))
- error ("This frame inner-to next frame (corrupt stack?)");
-
- /* Check that this and the next frame are different. If they are
- not, there is most likely a stack cycle. As with the inner-than
- test, avoid the inner-most and sentinel frames. */
- /* FIXME: cagney/2003-03-17: Can't yet enable this this check. The
- frame_id_eq() method doesn't yet use function addresses when
- comparing frame IDs. */
- if (0
- && this_frame->level > 0
- && frame_id_eq (get_frame_id (this_frame),
- get_frame_id (this_frame->next)))
- error ("This frame identical to next frame (corrupt stack?)");
-
- /* 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
- frame->next to pull some fancy tricks (of course such code is, by
- definition, recursive). Try to prevent it.
-
- There is no reason to worry about memory leaks, should the
- remainder of the function fail. The allocated memory will be
- quickly reclaimed when the frame cache is flushed, and the `we've
- been here before' check above will stop repeated memory
- allocation calls. */
- prev_frame = FRAME_OBSTACK_ZALLOC (struct frame_info);
- prev_frame->level = this_frame->level + 1;
-
- /* Try to unwind the PC. If that doesn't work, assume we've reached
- the oldest frame and simply return. Is there a better sentinal
- value? The unwound PC value is then used to initialize the new
- previous frame's type.
-
- Note that the pc-unwind is intentionally performed before the
- frame chain. This is ok since, for old targets, both
- frame_pc_unwind (nee, FRAME_SAVED_PC) and
- DEPRECATED_FRAME_CHAIN()) assume THIS_FRAME's data structures
- have already been initialized (using
- DEPRECATED_INIT_EXTRA_FRAME_INFO) and hence the call order
- doesn't matter.
-
- By unwinding the PC first, it becomes possible to, in the case of
- a dummy frame, avoid also unwinding the frame ID. This is
- because (well ignoring the PPC) a dummy frame can be located
- using THIS_FRAME's frame ID. */
-
- if (frame_pc_unwind (this_frame) == 0)
+ && get_frame_type (this_frame) == NORMAL_FRAME
+ && get_frame_type (get_next_frame (this_frame)) == NORMAL_FRAME
+ && get_frame_pc (this_frame) == 0)
{
- /* The allocated PREV_FRAME will be reclaimed when the frame
- obstack is next purged. */
- if (frame_debug)
- {
- fprintf_unfiltered (gdb_stdlog, "-> ");
- fprint_frame (gdb_stdlog, NULL);
- fprintf_unfiltered (gdb_stdlog, " // unwound PC zero }\n");
- }
+ frame_debug_got_null_frame (gdb_stdlog, this_frame, "zero PC");
return NULL;
}
- /* Don't yet compute ->unwind (and hence ->type). It is computed
- on-demand in get_frame_type, frame_register_unwind, and
- get_frame_id. */
-
- /* Don't yet compute the frame's ID. It is computed on-demand by
- get_frame_id(). */
-
- /* The unwound frame ID is validate at the start of this function,
- as part of the logic to decide if that frame should be further
- unwound, and not here while the prev frame is being created.
- Doing this makes it possible for the user to examine a frame that
- has an invalid frame ID.
+ return get_prev_frame_1 (this_frame);
+}
- Some very old VAX code noted: [...] For the sake of argument,
- suppose that the stack is somewhat trashed (which is one reason
- that "info frame" exists). So, return 0 (indicating we don't
- know the address of the arglist) if we don't know what frame this
- frame calls. */
+CORE_ADDR
+get_frame_pc (struct frame_info *frame)
+{
+ gdb_assert (frame->next != NULL);
+ return frame_pc_unwind (frame->next);
+}
- /* Link it in. */
- this_frame->prev = prev_frame;
- prev_frame->next = this_frame;
+/* Return an address of that falls within the frame's code block. */
- if (frame_debug)
- {
- fprintf_unfiltered (gdb_stdlog, "-> ");
- fprint_frame (gdb_stdlog, prev_frame);
- fprintf_unfiltered (gdb_stdlog, " }\n");
- }
+CORE_ADDR
+frame_unwind_address_in_block (struct frame_info *next_frame)
+{
+ /* A draft address. */
+ CORE_ADDR pc = frame_pc_unwind (next_frame);
- return prev_frame;
+ /* If THIS frame is not inner most (i.e., NEXT isn't the sentinel),
+ and NEXT is `normal' (i.e., not a sigtramp, dummy, ....) THIS
+ frame's PC ends up pointing at the instruction fallowing the
+ "call". Adjust that PC value so that it falls on the call
+ instruction (which, hopefully, falls within THIS frame's code
+ block. So far it's proved to be a very good approximation. See
+ get_frame_type() for why ->type can't be used. */
+ if (next_frame->level >= 0
+ && get_frame_type (next_frame) == NORMAL_FRAME)
+ --pc;
+ return pc;
}
CORE_ADDR
-get_frame_pc (struct frame_info *frame)
+get_frame_address_in_block (struct frame_info *this_frame)
{
- gdb_assert (frame->next != NULL);
- return frame_pc_unwind (frame->next);
+ return frame_unwind_address_in_block (this_frame->next);
}
static int
if (get_frame_type (fi) != NORMAL_FRAME)
return 0;
if (fi->base == NULL)
- fi->base = frame_base_find_by_pc (current_gdbarch, get_frame_pc (fi));
+ fi->base = frame_base_find_by_frame (fi->next);
/* Sneaky: If the low-level unwind and high-level base code share a
common unwinder, let them share the prologue cache. */
if (fi->base->unwind == fi->unwind)
return 0;
/* If there isn't a frame address method, find it. */
if (fi->base == NULL)
- fi->base = frame_base_find_by_pc (current_gdbarch, get_frame_pc (fi));
+ fi->base = frame_base_find_by_frame (fi->next);
/* Sneaky: If the low-level unwind and high-level base code share a
common unwinder, let them share the prologue cache. */
if (fi->base->unwind == fi->unwind)
return 0;
/* If there isn't a frame address method, find it. */
if (fi->base == NULL)
- fi->base = frame_base_find_by_pc (current_gdbarch, get_frame_pc (fi));
+ fi->base = frame_base_find_by_frame (fi->next);
/* Sneaky: If the low-level unwind and high-level base code share a
common unwinder, let them share the prologue cache. */
if (fi->base->unwind == fi->unwind)
enum frame_type
get_frame_type (struct frame_info *frame)
{
- /* Some targets still don't use [generic] dummy frames. Catch them
- here. */
- if (!DEPRECATED_USE_GENERIC_DUMMY_FRAMES
- && deprecated_frame_in_dummy (frame))
- return DUMMY_FRAME;
-
- /* Some legacy code, e.g, mips_init_extra_frame_info() wants
- to determine the frame's type prior to it being completely
- initialized. Don't attempt to lazily initialize ->unwind for
- legacy code. It will be initialized in legacy_get_prev_frame(). */
- if (frame->unwind == NULL && !legacy_frame_p (current_gdbarch))
- {
- /* Initialize the frame's unwinder because it is that which
- provides the frame's type. */
- frame->unwind = frame_unwind_find_by_pc (current_gdbarch,
- get_frame_pc (frame));
- /* FIXME: cagney/2003-04-02: Rather than storing the frame's
- type in the frame, the unwinder's type should be returned
- directly. Unfortunatly, legacy code, called by
- legacy_get_prev_frame, explicitly set the frames type using
- the method deprecated_set_frame_type(). */
- gdb_assert (frame->unwind->type != UNKNOWN_FRAME);
- frame->type = frame->unwind->type;
- }
- if (frame->type == UNKNOWN_FRAME)
- return NORMAL_FRAME;
- else
- return frame->type;
-}
-
-void
-deprecated_set_frame_type (struct frame_info *frame, enum frame_type type)
-{
- /* Arrrg! See comment in "frame.h". */
- frame->type = type;
-}
-
-struct frame_extra_info *
-get_frame_extra_info (struct frame_info *fi)
-{
- return fi->extra_info;
-}
-
-struct frame_extra_info *
-frame_extra_info_zalloc (struct frame_info *fi, long size)
-{
- fi->extra_info = frame_obstack_zalloc (size);
- return fi->extra_info;
+ if (frame->unwind == NULL)
+ /* Initialize the frame's unwinder because that's what
+ provides the frame's type. */
+ frame->unwind = frame_unwind_find_by_frame (frame->next,
+ &frame->prologue_cache);
+ return frame->unwind->type;
}
void
"{ deprecated_update_frame_pc_hack (frame=%d,pc=0x%s) }\n",
frame->level, paddr_nz (pc));
/* NOTE: cagney/2003-03-11: Some architectures (e.g., Arm) are
- maintaining a locally allocated frame object. Since such frame's
+ maintaining a locally allocated frame object. Since such frames
are not in the frame chain, it isn't possible to assume that the
frame has a next. Sigh. */
if (frame->next != NULL)
frame->this_id.value.stack_addr = base;
}
-void
-deprecated_set_frame_saved_regs_hack (struct frame_info *frame,
- CORE_ADDR *saved_regs)
-{
- frame->saved_regs = saved_regs;
-}
-
-void
-deprecated_set_frame_extra_info_hack (struct frame_info *frame,
- struct frame_extra_info *extra_info)
-{
- frame->extra_info = extra_info;
-}
-
-void
-deprecated_set_frame_next_hack (struct frame_info *fi,
- struct frame_info *next)
-{
- fi->next = next;
-}
-
-void
-deprecated_set_frame_prev_hack (struct frame_info *fi,
- struct frame_info *prev)
-{
- fi->prev = prev;
-}
-
-struct context *
-deprecated_get_frame_context (struct frame_info *fi)
-{
- return fi->context;
-}
-
-void
-deprecated_set_frame_context (struct frame_info *fi,
- struct context *context)
-{
- fi->context = context;
-}
-
-struct frame_info *
-deprecated_frame_xmalloc (void)
-{
- struct frame_info *frame = FRAME_OBSTACK_ZALLOC (struct frame_info);
- frame->this_id.p = 1;
- return frame;
-}
-
-struct frame_info *
-deprecated_frame_xmalloc_with_cleanup (long sizeof_saved_regs,
- long sizeof_extra_info)
-{
- struct frame_info *frame = deprecated_frame_xmalloc ();
- make_cleanup (xfree, frame);
- if (sizeof_saved_regs > 0)
- {
- frame->saved_regs = xcalloc (1, sizeof_saved_regs);
- make_cleanup (xfree, frame->saved_regs);
- }
- if (sizeof_extra_info > 0)
- {
- frame->extra_info = xcalloc (1, sizeof_extra_info);
- make_cleanup (xfree, frame->extra_info);
- }
- return frame;
-}
-
/* 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);
}
return read_memory_unsigned_integer (addr, len);
}
+int
+safe_frame_unwind_memory (struct frame_info *this_frame,
+ CORE_ADDR addr, gdb_byte *buf, int len)
+{
+ /* NOTE: read_memory_nobpt returns zero on success! */
+ return !read_memory_nobpt (addr, buf, len);
+}
+
/* Architecture method. */
struct gdbarch *
CORE_ADDR
frame_sp_unwind (struct frame_info *next_frame)
{
- /* Normality, an architecture that provides a way of obtaining any
+ /* Normality - an architecture that provides a way of obtaining any
frame inner-most address. */
if (gdbarch_unwind_sp_p (current_gdbarch))
return gdbarch_unwind_sp (current_gdbarch, next_frame);
/* Things are looking grim. If it's the inner-most frame and there
- is a TARGET_READ_SP then that can be used. */
+ is a TARGET_READ_SP, then that can be used. */
if (next_frame->level < 0 && TARGET_READ_SP_P ())
return TARGET_READ_SP ();
/* Now things are really are grim. Hope that the value returned by
frame_unwind_unsigned_register (next_frame, SP_REGNUM, &sp);
return sp;
}
- internal_error (__FILE__, __LINE__, "Missing unwind SP method");
+ internal_error (__FILE__, __LINE__, _("Missing unwind SP method"));
}
+/* Return the reason why we can't unwind past FRAME. */
-int
-legacy_frame_p (struct gdbarch *current_gdbarch)
+enum unwind_stop_reason
+get_frame_unwind_stop_reason (struct frame_info *frame)
{
- return (DEPRECATED_INIT_FRAME_PC_P ()
- || DEPRECATED_INIT_FRAME_PC_FIRST_P ()
- || DEPRECATED_INIT_EXTRA_FRAME_INFO_P ()
- || DEPRECATED_FRAME_CHAIN_P ()
- || !gdbarch_unwind_dummy_id_p (current_gdbarch));
+ /* 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;
+static struct cmd_list_element *show_backtrace_cmdlist;
+
+static void
+set_backtrace_cmd (char *args, int from_tty)
+{
+ help_list (set_backtrace_cmdlist, "set backtrace ", -1, gdb_stdout);
+}
+
+static void
+show_backtrace_cmd (char *args, int from_tty)
+{
+ cmd_show_list (show_backtrace_cmdlist, from_tty, "");
+}
+
void
_initialize_frame (void)
{
obstack_init (&frame_cache_obstack);
- /* FIXME: cagney/2003-01-19: This command needs a rename. Suggest
- `set backtrace {past,beyond,...}-main'. Also suggest adding `set
- backtrace ...-start' to control backtraces past start. The
- problem with `below' is that it stops the `up' command. */
-
- add_setshow_boolean_cmd ("backtrace-below-main", class_obscure,
- &backtrace_below_main, "\
-Set whether backtraces should continue past \"main\".\n\
-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.", "\
-Show whether backtraces should continue past \"main\".\n\
+ observer_attach_target_changed (frame_observer_target_changed);
+
+ add_prefix_cmd ("backtrace", class_maintenance, set_backtrace_cmd, _("\
+Set backtrace specific variables.\n\
+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, _("\
+Show backtrace specific variables\n\
+Show backtrace variables such as the backtrace limit"),
+ &show_backtrace_cmdlist, "show backtrace ",
+ 0/*allow-unknown*/, &showlist);
+
+ add_setshow_boolean_cmd ("past-main", class_obscure,
+ &backtrace_past_main, _("\
+Set whether backtraces should continue past \"main\"."), _("\
+Show whether backtraces should continue past \"main\"."), _("\
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, NULL, &setlist, &showlist);
-
+of the stack trace."),
+ NULL,
+ show_backtrace_past_main,
+ &set_backtrace_cmdlist,
+ &show_backtrace_cmdlist);
+
+ add_setshow_boolean_cmd ("past-entry", class_obscure,
+ &backtrace_past_entry, _("\
+Set whether backtraces should continue past the entry point of a program."),
+ _("\
+Show whether backtraces should continue past the entry point of a program."),
+ _("\
+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,
+ show_backtrace_past_entry,
+ &set_backtrace_cmdlist,
+ &show_backtrace_cmdlist);
+
+ 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,
+ show_backtrace_limit,
+ &set_backtrace_cmdlist,
+ &show_backtrace_cmdlist);
/* Debug this files internals. */
- 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);
}