to sigaltstack).
However, it can be used as safety net to discover invalid frame
- IDs in certain circumstances. Assuming that NEXT is the immediate
+ IDs in certain circumstances. Assuming that NEXT is the immediate
inner frame to THIS and that NEXT and THIS are both NORMAL frames:
* The stack address of NEXT must be inner-than-or-equal to the stack
is involved, because signal handlers might be executed on a different
stack than the stack used by the routine that caused the signal
to be raised. This can happen for instance when a thread exceeds
- its maximum stack size. In this case, certain compilers implement
+ its maximum stack size. In this case, certain compilers implement
a stack overflow strategy that cause the handler to be run on a
different stack. */
return NULL;
}
-static CORE_ADDR
-frame_unwind_pc (struct frame_info *this_frame)
+static int
+frame_unwind_pc_if_available (struct frame_info *this_frame, CORE_ADDR *pc)
{
if (!this_frame->prev_pc.p)
{
- CORE_ADDR pc;
-
if (gdbarch_unwind_pc_p (frame_unwind_arch (this_frame)))
{
+ volatile struct gdb_exception ex;
+ struct gdbarch *prev_gdbarch;
+ CORE_ADDR pc = 0;
+
/* The right way. The `pure' way. The one true way. This
method depends solely on the register-unwind code to
determine the value of registers in THIS frame, and hence
frame. This is all in stark contrast to the old
FRAME_SAVED_PC which would try to directly handle all the
different ways that a PC could be unwound. */
- pc = gdbarch_unwind_pc (frame_unwind_arch (this_frame), this_frame);
+ prev_gdbarch = frame_unwind_arch (this_frame);
+
+ TRY_CATCH (ex, RETURN_MASK_ERROR)
+ {
+ pc = gdbarch_unwind_pc (prev_gdbarch, this_frame);
+ }
+ if (ex.reason < 0 && ex.error == NOT_AVAILABLE_ERROR)
+ {
+ this_frame->prev_pc.p = -1;
+
+ if (frame_debug)
+ fprintf_unfiltered (gdb_stdlog,
+ "{ frame_unwind_pc (this_frame=%d)"
+ " -> <unavailable> }\n",
+ this_frame->level);
+ }
+ else if (ex.reason < 0)
+ {
+ throw_exception (ex);
+ }
+ else
+ {
+ this_frame->prev_pc.value = pc;
+ this_frame->prev_pc.p = 1;
+ if (frame_debug)
+ fprintf_unfiltered (gdb_stdlog,
+ "{ frame_unwind_pc (this_frame=%d) "
+ "-> %s }\n",
+ this_frame->level,
+ hex_string (this_frame->prev_pc.value));
+ }
}
else
internal_error (__FILE__, __LINE__, _("No unwind_pc method"));
- this_frame->prev_pc.value = pc;
- this_frame->prev_pc.p = 1;
- if (frame_debug)
- fprintf_unfiltered (gdb_stdlog,
- "{ frame_unwind_caller_pc "
- "(this_frame=%d) -> %s }\n",
- this_frame->level,
- hex_string (this_frame->prev_pc.value));
}
- return this_frame->prev_pc.value;
+ if (this_frame->prev_pc.p < 0)
+ {
+ *pc = -1;
+ return 0;
+ }
+ else
+ {
+ *pc = this_frame->prev_pc.value;
+ return 1;
+ }
+}
+
+static CORE_ADDR
+frame_unwind_pc (struct frame_info *this_frame)
+{
+ CORE_ADDR pc;
+
+ if (!frame_unwind_pc_if_available (this_frame, &pc))
+ throw_error (NOT_AVAILABLE_ERROR, _("PC not available"));
+ else
+ return pc;
}
CORE_ADDR
return frame_unwind_pc (skip_inlined_frames (this_frame));
}
-CORE_ADDR
-get_frame_func (struct frame_info *this_frame)
+int
+frame_unwind_caller_pc_if_available (struct frame_info *this_frame,
+ CORE_ADDR *pc)
+{
+ return frame_unwind_pc_if_available (skip_inlined_frames (this_frame), pc);
+}
+
+int
+get_frame_func_if_available (struct frame_info *this_frame, CORE_ADDR *pc)
{
struct frame_info *next_frame = this_frame->next;
if (!next_frame->prev_func.p)
{
+ CORE_ADDR addr_in_block;
+
/* Make certain that this, and not the adjacent, function is
found. */
- CORE_ADDR addr_in_block = get_frame_address_in_block (this_frame);
- next_frame->prev_func.p = 1;
- next_frame->prev_func.addr = get_pc_function_start (addr_in_block);
- if (frame_debug)
- fprintf_unfiltered (gdb_stdlog,
- "{ get_frame_func (this_frame=%d) -> %s }\n",
- this_frame->level,
- hex_string (next_frame->prev_func.addr));
+ if (!get_frame_address_in_block_if_available (this_frame, &addr_in_block))
+ {
+ next_frame->prev_func.p = -1;
+ if (frame_debug)
+ fprintf_unfiltered (gdb_stdlog,
+ "{ get_frame_func (this_frame=%d)"
+ " -> unavailable }\n",
+ this_frame->level);
+ }
+ else
+ {
+ next_frame->prev_func.p = 1;
+ next_frame->prev_func.addr = get_pc_function_start (addr_in_block);
+ if (frame_debug)
+ fprintf_unfiltered (gdb_stdlog,
+ "{ get_frame_func (this_frame=%d) -> %s }\n",
+ this_frame->level,
+ hex_string (next_frame->prev_func.addr));
+ }
+ }
+
+ if (next_frame->prev_func.p < 0)
+ {
+ *pc = -1;
+ return 0;
+ }
+ else
+ {
+ *pc = next_frame->prev_func.addr;
+ return 1;
}
- return next_frame->prev_func.addr;
}
-static int
+CORE_ADDR
+get_frame_func (struct frame_info *this_frame)
+{
+ CORE_ADDR pc;
+
+ if (!get_frame_func_if_available (this_frame, &pc))
+ throw_error (NOT_AVAILABLE_ERROR, _("PC not available"));
+
+ return pc;
+}
+
+static enum register_status
do_frame_register_read (void *src, int regnum, gdb_byte *buf)
{
- return frame_register_read (src, regnum, buf);
+ if (!frame_register_read (src, regnum, buf))
+ return REG_UNAVAILABLE;
+ else
+ return REG_VALID;
}
struct regcache *
void
frame_register_unwind (struct frame_info *frame, int regnum,
- int *optimizedp, enum lval_type *lvalp,
- CORE_ADDR *addrp, int *realnump, gdb_byte *bufferp)
+ int *optimizedp, int *unavailablep,
+ enum lval_type *lvalp, CORE_ADDR *addrp,
+ int *realnump, gdb_byte *bufferp)
{
struct value *value;
gdb_assert (value != NULL);
*optimizedp = value_optimized_out (value);
+ *unavailablep = !value_entirely_available (value);
*lvalp = VALUE_LVAL (value);
*addrp = value_address (value);
*realnump = VALUE_REGNUM (value);
- if (bufferp && !*optimizedp)
- memcpy (bufferp, value_contents_all (value),
- TYPE_LENGTH (value_type (value)));
+ if (bufferp)
+ {
+ if (!*optimizedp && !*unavailablep)
+ memcpy (bufferp, value_contents_all (value),
+ TYPE_LENGTH (value_type (value)));
+ else
+ memset (bufferp, 0, TYPE_LENGTH (value_type (value)));
+ }
/* Dispose of the new value. This prevents watchpoints from
trying to watch the saved frame pointer. */
void
frame_register (struct frame_info *frame, int regnum,
- int *optimizedp, enum lval_type *lvalp,
+ int *optimizedp, int *unavailablep, enum lval_type *lvalp,
CORE_ADDR *addrp, int *realnump, gdb_byte *bufferp)
{
/* Require all but BUFFERP to be valid. A NULL BUFFERP indicates
/* Obtain the register value by unwinding the register from the next
(more inner frame). */
gdb_assert (frame != NULL && frame->next != NULL);
- frame_register_unwind (frame->next, regnum, optimizedp, lvalp, addrp,
- realnump, bufferp);
+ frame_register_unwind (frame->next, regnum, optimizedp, unavailablep,
+ lvalp, addrp, realnump, bufferp);
}
void
frame_unwind_register (struct frame_info *frame, int regnum, gdb_byte *buf)
{
int optimized;
+ int unavailable;
CORE_ADDR addr;
int realnum;
enum lval_type lval;
- frame_register_unwind (frame, regnum, &optimized, &lval, &addr,
- &realnum, buf);
+ frame_register_unwind (frame, regnum, &optimized, &unavailable,
+ &lval, &addr, &realnum, buf);
+
+ if (optimized)
+ error (_("Register %d was optimized out"), regnum);
+ if (unavailable)
+ throw_error (NOT_AVAILABLE_ERROR,
+ _("Register %d is not available"), regnum);
}
void
struct gdbarch *gdbarch = get_frame_arch (frame);
int realnum;
int optim;
+ int unavail;
enum lval_type lval;
CORE_ADDR addr;
- frame_register (frame, regnum, &optim, &lval, &addr, &realnum, NULL);
+ frame_register (frame, regnum, &optim, &unavail,
+ &lval, &addr, &realnum, NULL);
if (optim)
error (_("Attempt to assign to a value that was optimized out."));
switch (lval)
gdb_byte *myaddr)
{
int optimized;
+ int unavailable;
enum lval_type lval;
CORE_ADDR addr;
int realnum;
- frame_register (frame, regnum, &optimized, &lval, &addr, &realnum, myaddr);
+ frame_register (frame, regnum, &optimized, &unavailable,
+ &lval, &addr, &realnum, myaddr);
- return !optimized;
+ return !optimized && !unavailable;
}
int
get_frame_register_bytes (struct frame_info *frame, int regnum,
- CORE_ADDR offset, int len, gdb_byte *myaddr)
+ CORE_ADDR offset, int len, gdb_byte *myaddr,
+ int *optimizedp, int *unavailablep)
{
struct gdbarch *gdbarch = get_frame_arch (frame);
int i;
maxsize += thissize;
}
if (len > maxsize)
- {
- warning (_("Bad debug information detected: "
- "Attempt to read %d bytes from registers."), len);
- return 0;
- }
+ error (_("Bad debug information detected: "
+ "Attempt to read %d bytes from registers."), len);
/* Copy the data. */
while (len > 0)
if (curr_len == register_size (gdbarch, regnum))
{
- if (!frame_register_read (frame, regnum, myaddr))
+ enum lval_type lval;
+ CORE_ADDR addr;
+ int realnum;
+
+ frame_register (frame, regnum, optimizedp, unavailablep,
+ &lval, &addr, &realnum, myaddr);
+ if (*optimizedp || *unavailablep)
return 0;
}
else
{
gdb_byte buf[MAX_REGISTER_SIZE];
+ enum lval_type lval;
+ CORE_ADDR addr;
+ int realnum;
- if (!frame_register_read (frame, regnum, buf))
+ frame_register (frame, regnum, optimizedp, unavailablep,
+ &lval, &addr, &realnum, buf);
+ if (*optimizedp || *unavailablep)
return 0;
memcpy (myaddr, buf + offset, curr_len);
}
regnum++;
}
+ *optimizedp = 0;
+ *unavailablep = 0;
return 1;
}
return frame;
}
-/* Info about the innermost stack frame (contents of FP register) */
+/* Info about the innermost stack frame (contents of FP register). */
static struct frame_info *current_frame;
return selected_frame;
}
+/* If there is a selected frame, return it. Otherwise, return NULL. */
+
+struct frame_info *
+get_selected_frame_if_set (void)
+{
+ return 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(). */
void
select_frame (struct frame_info *fi)
{
- struct symtab *s;
-
selected_frame = fi;
/* NOTE: cagney/2002-05-04: FI can be NULL. This occurs when the
frame is being invalidated. */
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 user's 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)
{
- /* 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
- && language_mode == language_mode_auto)
+ CORE_ADDR pc;
+
+ /* 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. */
+ if (get_frame_address_in_block_if_available (fi, &pc))
{
- set_language (s->language);
+ struct symtab *s = find_pc_symtab (pc);
+
+ if (s
+ && s->language != current_language->la_language
+ && s->language != language_unknown
+ && language_mode == language_mode_auto)
+ set_language (s->language);
}
}
}
-
+
/* Create an arbitrary (i.e. address specified by user) or innermost frame.
Always returns a non-NULL value. */
fi->base->unwind->dealloc_cache (fi, fi->base_cache);
}
- /* Since we can't really be sure what the first object allocated was */
+ /* Since we can't really be sure what the first object allocated was. */
obstack_free (&frame_cache_obstack, 0);
obstack_init (&frame_cache_obstack);
while (this_frame != NULL)
{
- frame_register_unwind (this_frame, regnum, optimizedp, lvalp,
- addrp, realnump, NULL);
+ int unavailable;
+
+ frame_register_unwind (this_frame, regnum, optimizedp, &unavailable,
+ lvalp, addrp, realnump, NULL);
if (*optimizedp)
break;
if (get_frame_type (this_frame) == INLINE_FRAME)
return get_prev_frame_raw (this_frame);
+ /* Check that this frame is unwindable. If it isn't, don't try to
+ unwind to the prev frame. */
+ this_frame->stop_reason
+ = this_frame->unwind->stop_reason (this_frame,
+ &this_frame->prologue_cache);
+
+ if (this_frame->stop_reason != UNWIND_NO_REASON)
+ return NULL;
+
/* 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. */
struct frame_info *
get_prev_frame (struct frame_info *this_frame)
{
+ CORE_ADDR frame_pc;
+ int frame_pc_p;
+
/* There is always a frame. If this assertion fails, suspect that
something should be calling get_selected_frame() or
get_current_frame(). */
gdb_assert (this_frame != NULL);
+ frame_pc_p = get_frame_pc_if_available (this_frame, &frame_pc);
/* 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
if (this_frame->level >= 0
&& get_frame_type (this_frame) == NORMAL_FRAME
&& !backtrace_past_main
+ && frame_pc_p
&& 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
if (this_frame->level >= 0
&& get_frame_type (this_frame) == NORMAL_FRAME
&& !backtrace_past_entry
+ && frame_pc_p
&& inside_entry_func (this_frame))
{
frame_debug_got_null_frame (this_frame, "inside entry func");
&& (get_frame_type (this_frame) == NORMAL_FRAME
|| get_frame_type (this_frame) == INLINE_FRAME)
&& get_frame_type (get_next_frame (this_frame)) == NORMAL_FRAME
- && get_frame_pc (this_frame) == 0)
+ && frame_pc_p && frame_pc == 0)
{
frame_debug_got_null_frame (this_frame, "zero PC");
return NULL;
return frame_unwind_pc (frame->next);
}
+int
+get_frame_pc_if_available (struct frame_info *frame, CORE_ADDR *pc)
+{
+ volatile struct gdb_exception ex;
+
+ gdb_assert (frame->next != NULL);
+
+ TRY_CATCH (ex, RETURN_MASK_ERROR)
+ {
+ *pc = frame_unwind_pc (frame->next);
+ }
+ if (ex.reason < 0)
+ {
+ if (ex.error == NOT_AVAILABLE_ERROR)
+ return 0;
+ else
+ throw_exception (ex);
+ }
+
+ return 1;
+}
+
/* Return an address that falls within THIS_FRAME's code block. */
CORE_ADDR
return pc;
}
+int
+get_frame_address_in_block_if_available (struct frame_info *this_frame,
+ CORE_ADDR *pc)
+{
+ volatile struct gdb_exception ex;
+
+ TRY_CATCH (ex, RETURN_MASK_ERROR)
+ {
+ *pc = get_frame_address_in_block (this_frame);
+ }
+ if (ex.reason < 0 && ex.error == NOT_AVAILABLE_ERROR)
+ return 0;
+ else if (ex.reason < 0)
+ throw_exception (ex);
+ else
+ return 1;
+}
+
void
find_frame_sal (struct frame_info *frame, struct symtab_and_line *sal)
{
struct frame_info *next_frame;
int notcurrent;
+ CORE_ADDR pc;
/* If the next frame represents an inlined function call, this frame's
sal is the "call site" of that inlined function, which can not
else
sym = inline_skipped_symbol (inferior_ptid);
+ /* If frame is inline, it certainly has symbols. */
+ gdb_assert (sym);
init_sal (sal);
if (SYMBOL_LINE (sym) != 0)
{
PC and such a PC indicates the current (rather than next)
instruction/line, consequently, for such cases, want to get the
line containing fi->pc. */
- notcurrent = (get_frame_pc (frame) != get_frame_address_in_block (frame));
- (*sal) = find_pc_line (get_frame_pc (frame), notcurrent);
+ if (!get_frame_pc_if_available (frame, &pc))
+ {
+ init_sal (sal);
+ return;
+ }
+
+ notcurrent = (pc != get_frame_address_in_block (frame));
+ (*sal) = find_pc_line (pc, notcurrent);
}
/* Per "frame.h", return the ``address'' of the frame. Code should
case UNWIND_NULL_ID:
return _("unwinder did not report frame ID");
+ case UNWIND_UNAVAILABLE:
+ return _("Not enough registers or memory available to unwind further");
+
case UNWIND_INNER_ID:
return _("previous frame inner to this frame (corrupt stack?)");
&set_backtrace_cmdlist,
&show_backtrace_cmdlist);
- /* Debug this files internals. */
+ /* Debug this files internals. */
add_setshow_zinteger_cmd ("frame", class_maintenance, &frame_debug, _("\
Set frame debugging."), _("\
Show frame debugging."), _("\