/* Cache and manage frames for GDB, the GNU debugger.
- Copyright (C) 1986, 1987, 1989, 1991, 1994, 1995, 1996, 1998, 2000, 2001,
- 2002, 2003, 2004, 2007, 2008, 2009, 2010, 2011
- Free Software Foundation, Inc.
+ Copyright (C) 1986-2017 Free Software Foundation, Inc.
This file is part of GDB.
#include "value.h"
#include "inferior.h" /* for inferior_ptid */
#include "regcache.h"
-#include "gdb_assert.h"
-#include "gdb_string.h"
#include "user-regs.h"
#include "gdb_obstack.h"
#include "dummy-frame.h"
#include "gdbcmd.h"
#include "observer.h"
#include "objfiles.h"
-#include "exceptions.h"
#include "gdbthread.h"
#include "block.h"
#include "inline-frame.h"
-#include "tracepoint.h"
+#include "tracepoint.h"
+#include "hashtab.h"
+#include "valprint.h"
+
+/* The sentinel frame terminates the innermost end of the frame chain.
+ If unwound, it returns the information needed to construct an
+ innermost frame.
+
+ The current frame, which is the innermost frame, can be found at
+ sentinel_frame->prev. */
+
+static struct frame_info *sentinel_frame;
-static struct frame_info *get_prev_frame_1 (struct frame_info *this_frame);
static struct frame_info *get_prev_frame_raw (struct frame_info *this_frame);
+static const char *frame_stop_reason_symbol_string (enum unwind_stop_reason reason);
+
+/* Status of some values cached in the frame_info object. */
+
+enum cached_copy_status
+{
+ /* Value is unknown. */
+ CC_UNKNOWN,
+
+ /* We have a value. */
+ CC_VALUE,
+
+ /* Value was not saved. */
+ CC_NOT_SAVED,
+
+ /* Value is unavailable. */
+ CC_UNAVAILABLE
+};
/* We keep a cache of stack frames, each of which is a "struct
frame_info". The innermost one gets allocated (in
- wait_for_inferior) each time the inferior stops; current_frame
+ wait_for_inferior) each time the inferior stops; sentinel_frame
points to it. Additional frames get allocated (in get_prev_frame)
as needed, and are chained through the next and prev fields. Any
time that the frame cache becomes invalid (most notably when we
/* Cached copy of the previous frame's resume address. */
struct {
- int p;
+ enum cached_copy_status status;
CORE_ADDR value;
} prev_pc;
/* 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;
+
+ /* A frame specific string describing the STOP_REASON in more detail.
+ Only valid when PREV_P is set, but even then may still be NULL. */
+ const char *stop_string;
};
-/* A frame stash used to speed up frame lookups. */
+/* A frame stash used to speed up frame lookups. Create a hash table
+ to stash frames previously accessed from the frame cache for
+ quicker subsequent retrieval. The hash table is emptied whenever
+ the frame cache is invalidated. */
+
+static htab_t frame_stash;
-/* We currently only stash one frame at a time, as this seems to be
- sufficient for now. */
-static struct frame_info *frame_stash = NULL;
+/* Internal function to calculate a hash from the frame_id addresses,
+ using as many valid addresses as possible. Frames below level 0
+ are not stored in the hash table. */
+
+static hashval_t
+frame_addr_hash (const void *ap)
+{
+ const struct frame_info *frame = (const struct frame_info *) ap;
+ const struct frame_id f_id = frame->this_id.value;
+ hashval_t hash = 0;
+
+ gdb_assert (f_id.stack_status != FID_STACK_INVALID
+ || f_id.code_addr_p
+ || f_id.special_addr_p);
+
+ if (f_id.stack_status == FID_STACK_VALID)
+ hash = iterative_hash (&f_id.stack_addr,
+ sizeof (f_id.stack_addr), hash);
+ if (f_id.code_addr_p)
+ hash = iterative_hash (&f_id.code_addr,
+ sizeof (f_id.code_addr), hash);
+ if (f_id.special_addr_p)
+ hash = iterative_hash (&f_id.special_addr,
+ sizeof (f_id.special_addr), hash);
+
+ return hash;
+}
+
+/* Internal equality function for the hash table. This function
+ defers equality operations to frame_id_eq. */
+
+static int
+frame_addr_hash_eq (const void *a, const void *b)
+{
+ const struct frame_info *f_entry = (const struct frame_info *) a;
+ const struct frame_info *f_element = (const struct frame_info *) b;
+
+ return frame_id_eq (f_entry->this_id.value,
+ f_element->this_id.value);
+}
-/* Add the following FRAME to the frame stash. */
+/* Internal function to create the frame_stash hash table. 100 seems
+ to be a good compromise to start the hash table at. */
static void
+frame_stash_create (void)
+{
+ frame_stash = htab_create (100,
+ frame_addr_hash,
+ frame_addr_hash_eq,
+ NULL);
+}
+
+/* Internal function to add a frame to the frame_stash hash table.
+ Returns false if a frame with the same ID was already stashed, true
+ otherwise. */
+
+static int
frame_stash_add (struct frame_info *frame)
{
- frame_stash = frame;
+ struct frame_info **slot;
+
+ /* Do not try to stash the sentinel frame. */
+ gdb_assert (frame->level >= 0);
+
+ slot = (struct frame_info **) htab_find_slot (frame_stash,
+ frame,
+ INSERT);
+
+ /* If we already have a frame in the stack with the same id, we
+ either have a stack cycle (corrupted stack?), or some bug
+ elsewhere in GDB. In any case, ignore the duplicate and return
+ an indication to the caller. */
+ if (*slot != NULL)
+ return 0;
+
+ *slot = frame;
+ return 1;
}
-/* Search the frame stash for an entry with the given frame ID.
- If found, return that frame. Otherwise return NULL. */
+/* Internal function to search the frame stash for an entry with the
+ given frame ID. If found, return that frame. Otherwise return
+ NULL. */
static struct frame_info *
frame_stash_find (struct frame_id id)
{
- if (frame_stash && frame_id_eq (frame_stash->this_id.value, id))
- return frame_stash;
+ struct frame_info dummy;
+ struct frame_info *frame;
- return NULL;
+ dummy.this_id.value = id;
+ frame = (struct frame_info *) htab_find (frame_stash, &dummy);
+ return frame;
}
-/* Invalidate the frame stash by removing all entries in it. */
+/* Internal function to invalidate the frame stash by removing all
+ entries in it. This only occurs when the frame cache is
+ invalidated. */
static void
frame_stash_invalidate (void)
{
- frame_stash = NULL;
+ htab_empty (frame_stash);
}
/* Flag to control debugging. */
-int frame_debug;
+unsigned int frame_debug;
static void
show_frame_debug (struct ui_file *file, int from_tty,
struct cmd_list_element *c, const char *value)
value);
}
-static int backtrace_limit = INT_MAX;
+static unsigned int backtrace_limit = UINT_MAX;
static void
show_backtrace_limit (struct ui_file *file, int from_tty,
struct cmd_list_element *c, const char *value)
fprint_frame_id (struct ui_file *file, struct frame_id id)
{
fprintf_unfiltered (file, "{");
- fprint_field (file, "stack", id.stack_addr_p, id.stack_addr);
+
+ if (id.stack_status == FID_STACK_INVALID)
+ fprintf_unfiltered (file, "!stack");
+ else if (id.stack_status == FID_STACK_UNAVAILABLE)
+ fprintf_unfiltered (file, "stack=<unavailable>");
+ else if (id.stack_status == FID_STACK_SENTINEL)
+ fprintf_unfiltered (file, "stack=<sentinel>");
+ else
+ fprintf_unfiltered (file, "stack=%s", hex_string (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);
- if (id.inline_depth)
- fprintf_unfiltered (file, ",inlined=%d", id.inline_depth);
+
+ if (id.artificial_depth)
+ fprintf_unfiltered (file, ",artificial=%d", id.artificial_depth);
+
fprintf_unfiltered (file, "}");
}
case INLINE_FRAME:
fprintf_unfiltered (file, "INLINE_FRAME");
return;
- case SENTINEL_FRAME:
- fprintf_unfiltered (file, "SENTINEL_FRAME");
+ case TAILCALL_FRAME:
+ fprintf_unfiltered (file, "TAILCALL_FRAME");
return;
case SIGTRAMP_FRAME:
fprintf_unfiltered (file, "SIGTRAMP_FRAME");
case ARCH_FRAME:
fprintf_unfiltered (file, "ARCH_FRAME");
return;
+ case SENTINEL_FRAME:
+ fprintf_unfiltered (file, "SENTINEL_FRAME");
+ return;
default:
fprintf_unfiltered (file, "<unknown type>");
return;
fprintf_unfiltered (file, "<unknown>");
fprintf_unfiltered (file, ",");
fprintf_unfiltered (file, "pc=");
- if (fi->next != NULL && fi->next->prev_pc.p)
- fprintf_unfiltered (file, "%s", hex_string (fi->next->prev_pc.value));
- else
+ if (fi->next == NULL || fi->next->prev_pc.status == CC_UNKNOWN)
fprintf_unfiltered (file, "<unknown>");
+ else if (fi->next->prev_pc.status == CC_VALUE)
+ fprintf_unfiltered (file, "%s",
+ hex_string (fi->next->prev_pc.value));
+ else if (fi->next->prev_pc.status == CC_NOT_SAVED)
+ val_print_not_saved (file);
+ else if (fi->next->prev_pc.status == CC_UNAVAILABLE)
+ val_print_unavailable (file);
fprintf_unfiltered (file, ",");
fprintf_unfiltered (file, "id=");
if (fi->this_id.p)
fprintf_unfiltered (file, "}");
}
-/* Given FRAME, return the enclosing normal frame for inlined
- function frames. Otherwise return the original frame. */
+/* Given FRAME, return the enclosing frame as found in real frames read-in from
+ inferior memory. Skip any previous frames which were made up by GDB.
+ Return FRAME if FRAME is a non-artificial frame.
+ Return NULL if FRAME is the start of an artificial-only chain. */
static struct frame_info *
-skip_inlined_frames (struct frame_info *frame)
+skip_artificial_frames (struct frame_info *frame)
+{
+ /* Note we use get_prev_frame_always, 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 the user
+ sets a backtrace limit).
+
+ Note that for record targets we may get a frame chain that consists
+ of artificial frames only. */
+ while (get_frame_type (frame) == INLINE_FRAME
+ || get_frame_type (frame) == TAILCALL_FRAME)
+ {
+ frame = get_prev_frame_always (frame);
+ if (frame == NULL)
+ break;
+ }
+
+ return frame;
+}
+
+struct frame_info *
+skip_unwritable_frames (struct frame_info *frame)
{
- while (get_frame_type (frame) == INLINE_FRAME)
- frame = get_prev_frame (frame);
+ while (gdbarch_code_of_frame_writable (get_frame_arch (frame), frame) == 0)
+ {
+ frame = get_prev_frame (frame);
+ if (frame == NULL)
+ break;
+ }
+
+ return frame;
+}
+
+/* See frame.h. */
+
+struct frame_info *
+skip_tailcall_frames (struct frame_info *frame)
+{
+ while (get_frame_type (frame) == TAILCALL_FRAME)
+ {
+ /* Note that for record targets we may get a frame chain that consists of
+ tailcall frames only. */
+ frame = get_prev_frame (frame);
+ if (frame == NULL)
+ break;
+ }
return frame;
}
+/* Compute the frame's uniq ID that can be used to, later, re-find the
+ frame. */
+
+static void
+compute_frame_id (struct frame_info *fi)
+{
+ gdb_assert (!fi->this_id.p);
+
+ if (frame_debug)
+ fprintf_unfiltered (gdb_stdlog, "{ compute_frame_id (fi=%d) ",
+ fi->level);
+ /* Find the unwinder. */
+ if (fi->unwind == NULL)
+ frame_unwind_find_by_frame (fi, &fi->prologue_cache);
+ /* Find THIS frame's ID. */
+ /* Default to outermost if no ID is found. */
+ fi->this_id.value = outer_frame_id;
+ fi->unwind->this_id (fi, &fi->prologue_cache, &fi->this_id.value);
+ gdb_assert (frame_id_p (fi->this_id.value));
+ fi->this_id.p = 1;
+ if (frame_debug)
+ {
+ fprintf_unfiltered (gdb_stdlog, "-> ");
+ fprint_frame_id (gdb_stdlog, fi->this_id.value);
+ fprintf_unfiltered (gdb_stdlog, " }\n");
+ }
+}
+
/* Return a frame uniq ID that can be used to, later, re-find the
frame. */
if (!fi->this_id.p)
{
- if (frame_debug)
- fprintf_unfiltered (gdb_stdlog, "{ get_frame_id (fi=%d) ",
- fi->level);
- /* Find the unwinder. */
- if (fi->unwind == NULL)
- frame_unwind_find_by_frame (fi, &fi->prologue_cache);
- /* Find THIS frame's ID. */
- /* Default to outermost if no ID is found. */
- fi->this_id.value = outer_frame_id;
- fi->unwind->this_id (fi, &fi->prologue_cache, &fi->this_id.value);
- gdb_assert (frame_id_p (fi->this_id.value));
- fi->this_id.p = 1;
- if (frame_debug)
- {
- fprintf_unfiltered (gdb_stdlog, "-> ");
- fprint_frame_id (gdb_stdlog, fi->this_id.value);
- fprintf_unfiltered (gdb_stdlog, " }\n");
- }
+ int stashed;
+
+ /* If we haven't computed the frame id yet, then it must be that
+ this is the current frame. Compute it now, and stash the
+ result. The IDs of other frames are computed as soon as
+ they're created, in order to detect cycles. See
+ get_prev_frame_if_no_cycle. */
+ gdb_assert (fi->level == 0);
+
+ /* Compute. */
+ compute_frame_id (fi);
+
+ /* Since this is the first frame in the chain, this should
+ always succeed. */
+ stashed = frame_stash_add (fi);
+ gdb_assert (stashed);
}
- frame_stash_add (fi);
-
return fi->this_id.value;
}
struct frame_id
get_stack_frame_id (struct frame_info *next_frame)
{
- return get_frame_id (skip_inlined_frames (next_frame));
+ return get_frame_id (skip_artificial_frames (next_frame));
}
struct frame_id
{
struct frame_info *this_frame;
- /* Use get_prev_frame_1, 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. */
+ /* Use get_prev_frame_always, 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. */
- next_frame = skip_inlined_frames (next_frame);
- this_frame = get_prev_frame_1 (next_frame);
+ next_frame = skip_artificial_frames (next_frame);
+ if (next_frame == NULL)
+ return null_frame_id;
+
+ this_frame = get_prev_frame_always (next_frame);
if (this_frame)
- return get_frame_id (skip_inlined_frames (this_frame));
+ return get_frame_id (skip_artificial_frames (this_frame));
else
return null_frame_id;
}
-const struct frame_id null_frame_id; /* All zeros. */
-const struct frame_id outer_frame_id = { 0, 0, 0, 0, 0, 1, 0 };
+const struct frame_id null_frame_id = { 0 }; /* All zeros. */
+const struct frame_id sentinel_frame_id = { 0, 0, 0, FID_STACK_SENTINEL, 0, 1, 0 };
+const struct frame_id outer_frame_id = { 0, 0, 0, FID_STACK_INVALID, 0, 1, 0 };
struct frame_id
frame_id_build_special (CORE_ADDR stack_addr, CORE_ADDR code_addr,
struct frame_id id = null_frame_id;
id.stack_addr = stack_addr;
- id.stack_addr_p = 1;
+ id.stack_status = FID_STACK_VALID;
+ id.code_addr = code_addr;
+ id.code_addr_p = 1;
+ id.special_addr = special_addr;
+ id.special_addr_p = 1;
+ return id;
+}
+
+/* See frame.h. */
+
+struct frame_id
+frame_id_build_unavailable_stack (CORE_ADDR code_addr)
+{
+ struct frame_id id = null_frame_id;
+
+ id.stack_status = FID_STACK_UNAVAILABLE;
+ id.code_addr = code_addr;
+ id.code_addr_p = 1;
+ return id;
+}
+
+/* See frame.h. */
+
+struct frame_id
+frame_id_build_unavailable_stack_special (CORE_ADDR code_addr,
+ CORE_ADDR special_addr)
+{
+ struct frame_id id = null_frame_id;
+
+ id.stack_status = FID_STACK_UNAVAILABLE;
id.code_addr = code_addr;
id.code_addr_p = 1;
id.special_addr = special_addr;
struct frame_id id = null_frame_id;
id.stack_addr = stack_addr;
- id.stack_addr_p = 1;
+ id.stack_status = FID_STACK_VALID;
id.code_addr = code_addr;
id.code_addr_p = 1;
return id;
struct frame_id id = null_frame_id;
id.stack_addr = stack_addr;
- id.stack_addr_p = 1;
+ id.stack_status = FID_STACK_VALID;
return id;
}
int p;
/* The frame is valid iff it has a valid stack address. */
- p = l.stack_addr_p;
+ p = l.stack_status != FID_STACK_INVALID;
/* outer_frame_id is also valid. */
if (!p && memcmp (&l, &outer_frame_id, sizeof (l)) == 0)
p = 1;
}
int
-frame_id_inlined_p (struct frame_id l)
+frame_id_artificial_p (struct frame_id l)
{
if (!frame_id_p (l))
return 0;
- return (l.inline_depth != 0);
+ return (l.artificial_depth != 0);
}
int
{
int eq;
- if (!l.stack_addr_p && l.special_addr_p
- && !r.stack_addr_p && r.special_addr_p)
+ if (l.stack_status == FID_STACK_INVALID && l.special_addr_p
+ && r.stack_status == FID_STACK_INVALID && r.special_addr_p)
/* The outermost frame marker is equal to itself. This is the
dodgy thing about outer_frame_id, since between execution steps
we might step into another function - from which we can't
unwind either. More thought required to get rid of
outer_frame_id. */
eq = 1;
- else if (!l.stack_addr_p || !r.stack_addr_p)
+ else if (l.stack_status == FID_STACK_INVALID
+ || r.stack_status == FID_STACK_INVALID)
/* 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)
+ else if (l.stack_status != r.stack_status || l.stack_addr != r.stack_addr)
/* If .stack addresses are different, the frames are different. */
eq = 0;
else if (l.code_addr_p && r.code_addr_p && l.code_addr != r.code_addr)
/* An invalid special addr is a wild card (or unused). Otherwise
if special addresses are different, the frames are different. */
eq = 0;
- else if (l.inline_depth != r.inline_depth)
- /* If inline depths are different, the frames must be different. */
+ else if (l.artificial_depth != r.artificial_depth)
+ /* If artifical depths are different, the frames must be different. */
eq = 0;
else
/* Frames are equal. */
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. */
{
int inner;
- if (!l.stack_addr_p || !r.stack_addr_p)
- /* Like NaN, any operation involving an invalid ID always fails. */
+ if (l.stack_status != FID_STACK_VALID || r.stack_status != FID_STACK_VALID)
+ /* Like NaN, any operation involving an invalid ID always fails.
+ Likewise if either ID has an unavailable stack address. */
inner = 0;
- else if (l.inline_depth > r.inline_depth
+ else if (l.artificial_depth > r.artificial_depth
&& l.stack_addr == r.stack_addr
&& l.code_addr_p == r.code_addr_p
&& l.special_addr_p == r.special_addr_p
&& l.special_addr == r.special_addr)
{
/* Same function, different inlined functions. */
- struct block *lb, *rb;
+ const struct block *lb, *rb;
gdb_assert (l.code_addr_p && r.code_addr_p);
if (!frame_id_p (id))
return NULL;
+ /* Check for the sentinel frame. */
+ if (frame_id_eq (id, sentinel_frame_id))
+ return sentinel_frame;
+
/* Try using the frame stash first. Finding it there removes the need
to perform the search by looping over all frames, which can be very
CPU-intensive if the number of frames is very high (the loop is O(n)
for (frame = get_current_frame (); ; frame = prev_frame)
{
- struct frame_id this = get_frame_id (frame);
+ struct frame_id self = get_frame_id (frame);
- if (frame_id_eq (id, this))
+ if (frame_id_eq (id, self))
/* An exact match. */
return frame;
frame in the current frame chain can have this ID. See the
comment at frame_id_inner for details. */
if (get_frame_type (frame) == NORMAL_FRAME
- && !frame_id_inner (get_frame_arch (frame), id, this)
+ && !frame_id_inner (get_frame_arch (frame), id, self)
&& frame_id_inner (get_frame_arch (prev_frame), id,
get_frame_id (prev_frame)))
return NULL;
static CORE_ADDR
frame_unwind_pc (struct frame_info *this_frame)
{
- if (!this_frame->prev_pc.p)
+ if (this_frame->prev_pc.status == CC_UNKNOWN)
{
- CORE_ADDR pc;
-
if (gdbarch_unwind_pc_p (frame_unwind_arch (this_frame)))
{
+ struct gdbarch *prev_gdbarch;
+ CORE_ADDR pc = 0;
+ int pc_p = 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
+ {
+ pc = gdbarch_unwind_pc (prev_gdbarch, this_frame);
+ pc_p = 1;
+ }
+ CATCH (ex, RETURN_MASK_ERROR)
+ {
+ if (ex.error == NOT_AVAILABLE_ERROR)
+ {
+ this_frame->prev_pc.status = CC_UNAVAILABLE;
+
+ if (frame_debug)
+ fprintf_unfiltered (gdb_stdlog,
+ "{ frame_unwind_pc (this_frame=%d)"
+ " -> <unavailable> }\n",
+ this_frame->level);
+ }
+ else if (ex.error == OPTIMIZED_OUT_ERROR)
+ {
+ this_frame->prev_pc.status = CC_NOT_SAVED;
+
+ if (frame_debug)
+ fprintf_unfiltered (gdb_stdlog,
+ "{ frame_unwind_pc (this_frame=%d)"
+ " -> <not saved> }\n",
+ this_frame->level);
+ }
+ else
+ throw_exception (ex);
+ }
+ END_CATCH
+
+ if (pc_p)
+ {
+ this_frame->prev_pc.value = pc;
+ this_frame->prev_pc.status = CC_VALUE;
+ 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.status == CC_VALUE)
+ return this_frame->prev_pc.value;
+ else if (this_frame->prev_pc.status == CC_UNAVAILABLE)
+ throw_error (NOT_AVAILABLE_ERROR, _("PC not available"));
+ else if (this_frame->prev_pc.status == CC_NOT_SAVED)
+ throw_error (OPTIMIZED_OUT_ERROR, _("PC not saved"));
+ else
+ internal_error (__FILE__, __LINE__,
+ "unexpected prev_pc status: %d",
+ (int) this_frame->prev_pc.status);
}
CORE_ADDR
frame_unwind_caller_pc (struct frame_info *this_frame)
{
- return frame_unwind_pc (skip_inlined_frames (this_frame));
+ this_frame = skip_artificial_frames (this_frame);
+
+ /* We must have a non-artificial frame. The caller is supposed to check
+ the result of frame_unwind_caller_id (), which returns NULL_FRAME_ID
+ in this case. */
+ gdb_assert (this_frame != NULL);
+
+ return frame_unwind_pc (this_frame);
}
-CORE_ADDR
-get_frame_func (struct frame_info *this_frame)
+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 (!deprecated_frame_register_read ((struct frame_info *) src, regnum, buf))
+ return REG_UNAVAILABLE;
+ else
+ return REG_VALID;
}
struct regcache *
{
/* Popping a dummy frame involves restoring more than just registers.
dummy_frame_pop does all the work. */
- dummy_frame_pop (get_frame_id (this_frame));
+ dummy_frame_pop (get_frame_id (this_frame), inferior_ptid);
return;
}
/* Ensure that we have a frame to pop to. */
- prev_frame = get_prev_frame_1 (this_frame);
+ prev_frame = get_prev_frame_always (this_frame);
if (!prev_frame)
error (_("Cannot pop the initial frame."));
+ /* Ignore TAILCALL_FRAME type frames, they were executed already before
+ entering THISFRAME. */
+ prev_frame = skip_tailcall_frames (prev_frame);
+
+ if (prev_frame == NULL)
+ error (_("Cannot find the caller frame."));
+
/* 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
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 (*lvalp == lval_register)
+ *realnump = VALUE_REGNUM (value);
+ else
+ *realnump = -1;
- 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)
+ throw_error (OPTIMIZED_OUT_ERROR,
+ _("Register %d was not saved"), regnum);
+ if (unavailable)
+ throw_error (NOT_AVAILABLE_ERROR,
+ _("Register %d is not available"), regnum);
}
void
{
fprintf_unfiltered (gdb_stdlog, "->");
if (value_optimized_out (value))
- fprintf_unfiltered (gdb_stdlog, " optimized out");
+ {
+ fprintf_unfiltered (gdb_stdlog, " ");
+ val_print_optimized_out (value, gdb_stdlog);
+ }
else
{
if (VALUE_LVAL (value) == lval_register)
return frame_unwind_register_unsigned (frame->next, regnum);
}
+int
+read_frame_register_unsigned (struct frame_info *frame, int regnum,
+ ULONGEST *val)
+{
+ struct value *regval = get_frame_register_value (frame, regnum);
+
+ if (!value_optimized_out (regval)
+ && value_entirely_available (regval))
+ {
+ struct gdbarch *gdbarch = get_frame_arch (frame);
+ enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
+ int size = register_size (gdbarch, VALUE_REGNUM (regval));
+
+ *val = extract_unsigned_integer (value_contents (regval), size, byte_order);
+ return 1;
+ }
+
+ return 0;
+}
+
void
put_frame_register (struct frame_info *frame, int regnum,
const gdb_byte *buf)
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."));
+ error (_("Attempt to assign to a register that was not saved."));
switch (lval)
{
case lval_memory:
{
- /* FIXME: write_memory doesn't yet take constant buffers.
- Arrrg! */
- gdb_byte tmp[MAX_REGISTER_SIZE];
-
- memcpy (tmp, buf, register_size (gdbarch, regnum));
- write_memory (addr, tmp, register_size (gdbarch, regnum));
+ write_memory (addr, buf, register_size (gdbarch, regnum));
break;
}
case lval_register:
}
}
-/* frame_register_read ()
+/* This function is deprecated. Use get_frame_register_value instead,
+ which provides more accurate information.
Find and return the value of REGNUM for the specified stack frame.
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,
+deprecated_frame_register_read (struct frame_info *frame, int regnum,
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;
}
{
gdb_byte buf[MAX_REGISTER_SIZE];
- frame_register_read (frame, regnum, buf);
+ deprecated_frame_register_read (frame, regnum, buf);
memcpy (buf + offset, myaddr, curr_len);
put_frame_register (frame, regnum, buf);
}
/* Link this frame back to itself. The frame is self referential
(the unwound PC is the same as the pc), so make it so. */
frame->next = frame;
- /* Make the sentinel frame's ID valid, but invalid. That way all
- comparisons with it should fail. */
+ /* The sentinel frame has a special ID. */
frame->this_id.p = 1;
- frame->this_id.value = null_frame_id;
+ frame->this_id.value = sentinel_frame_id;
if (frame_debug)
{
fprintf_unfiltered (gdb_stdlog, "{ create_sentinel_frame (...) -> ");
return frame;
}
-/* Info about the innermost stack frame (contents of FP register) */
-
-static struct frame_info *current_frame;
-
/* Cache for frame addresses already read by gdb. Valid only while
inferior is stopped. Control variables for the frame cache should
be local to this module. */
return data;
}
-/* 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
- sentinel frame fails, the function still returns a stack frame. */
-
-static int
-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, e.g., because its PC value
- lands in somewhere like start. */
- if (frame == NULL)
- return 1;
- current_frame = frame;
- return 0;
-}
+static struct frame_info *get_prev_frame_always_1 (struct frame_info *this_frame);
struct frame_info *
get_current_frame (void)
{
+ struct frame_info *current_frame;
+
/* First check, and report, the lack of registers. Having GDB
report "No stack!" or "No memory" when the target doesn't even
have registers is very confusing. Besides, "printcmd.exp"
error (_("No memory."));
/* Traceframes are effectively a substitute for the live inferior. */
if (get_traceframe_number () < 0)
- {
- if (ptid_equal (inferior_ptid, null_ptid))
- error (_("No selected thread."));
- if (is_exited (inferior_ptid))
- error (_("Invalid selected thread."));
- if (is_executing (inferior_ptid))
- error (_("Target is executing."));
- }
+ validate_registers_access ();
+
+ if (sentinel_frame == NULL)
+ sentinel_frame =
+ create_sentinel_frame (current_program_space, get_current_regcache ());
+
+ /* Set the current frame before computing the frame id, to avoid
+ recursion inside compute_frame_id, in case the frame's
+ unwinder decides to do a symbol lookup (which depends on the
+ selected frame's block).
+
+ This call must always succeed. In particular, nothing inside
+ get_prev_frame_always_1 should try to unwind from the
+ sentinel frame, because that could fail/throw, and we always
+ want to leave with the current frame created and linked in --
+ we should never end up with the sentinel frame as outermost
+ frame. */
+ current_frame = get_prev_frame_always_1 (sentinel_frame);
+ gdb_assert (current_frame != NULL);
- if (current_frame == NULL)
- {
- struct frame_info *sentinel_frame =
- create_sentinel_frame (current_program_space, get_current_regcache ());
- if (catch_exceptions (uiout, unwind_to_current_frame, sentinel_frame,
- RETURN_MASK_ERROR) != 0)
- {
- /* Oops! Fake a current frame? Is this useful? It has a PC
- of zero, for instance. */
- current_frame = sentinel_frame;
- }
- }
return current_frame;
}
if (!target_has_registers || !target_has_stack || !target_has_memory)
return 0;
- /* No current inferior, no frame. */
- if (ptid_equal (inferior_ptid, null_ptid))
- return 0;
+ /* Traceframes are effectively a substitute for the live inferior. */
+ if (get_traceframe_number () < 0)
+ {
+ /* No current inferior, no frame. */
+ if (ptid_equal (inferior_ptid, null_ptid))
+ return 0;
- /* Don't try to read from a dead thread. */
- if (is_exited (inferior_ptid))
- return 0;
+ /* Don't try to read from a dead thread. */
+ if (is_exited (inferior_ptid))
+ return 0;
- /* ... or from a spinning thread. */
- if (is_executing (inferior_ptid))
- return 0;
+ /* ... or from a spinning thread. */
+ if (is_executing (inferior_ptid))
+ return 0;
+ }
return 1;
}
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. */
- 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
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 compunit_symtab *cust = find_pc_compunit_symtab (pc);
+
+ if (cust != NULL
+ && compunit_language (cust) != current_language->la_language
+ && compunit_language (cust) != language_unknown
+ && language_mode == language_mode_auto)
+ set_language (compunit_language (cust));
}
}
}
-
+
/* Create an arbitrary (i.e. address specified by user) or innermost frame.
Always returns a non-NULL value. */
very likely to read this, and the corresponding unwinder is
entitled to rely that the PC doesn't magically change. */
fi->next->prev_pc.value = pc;
- fi->next->prev_pc.p = 1;
+ fi->next->prev_pc.status = CC_VALUE;
/* We currently assume that frame chain's can't cross spaces. */
fi->pspace = fi->next->pspace;
return NULL;
}
+/* Return the frame that THIS_FRAME calls. If THIS_FRAME is the
+ innermost (i.e. current) frame, return the sentinel frame. Thus,
+ unlike get_next_frame(), NULL will never be returned. */
+
+struct frame_info *
+get_next_frame_sentinel_okay (struct frame_info *this_frame)
+{
+ gdb_assert (this_frame != NULL);
+
+ /* Note that, due to the manner in which the sentinel frame is
+ constructed, this_frame->next still works even when this_frame
+ is the sentinel frame. But we disallow it here anyway because
+ calling get_next_frame_sentinel_okay() on the sentinel frame
+ is likely a coding error. */
+ gdb_assert (this_frame != sentinel_frame);
+
+ return this_frame->next;
+}
+
/* Observer for the target_changed event. */
static void
struct frame_info *fi;
/* Tear down all frame caches. */
- for (fi = current_frame; fi != NULL; fi = fi->prev)
+ for (fi = sentinel_frame; fi != NULL; fi = fi->prev)
{
if (fi->prologue_cache && fi->unwind->dealloc_cache)
fi->unwind->dealloc_cache (fi, fi->prologue_cache);
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);
- if (current_frame != NULL)
+ if (sentinel_frame != NULL)
annotate_frames_invalid ();
- current_frame = NULL; /* Invalidate cache */
+ sentinel_frame = NULL; /* Invalidate cache */
select_frame (NULL);
frame_stash_invalidate ();
if (frame_debug)
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;
}
}
-/* Return a "struct frame_info" corresponding to the frame that called
- THIS_FRAME. Returns NULL if there is no such frame.
+/* Called during frame unwinding to remove a previous frame pointer from a
+ frame passed in ARG. */
- Unlike get_prev_frame, this function always tries to unwind the
- frame. */
+static void
+remove_prev_frame (void *arg)
+{
+ struct frame_info *this_frame, *prev_frame;
+
+ this_frame = (struct frame_info *) arg;
+ prev_frame = this_frame->prev;
+ gdb_assert (prev_frame != NULL);
+
+ prev_frame->next = NULL;
+ this_frame->prev = NULL;
+}
+
+/* Get the previous raw frame, and check that it is not identical to
+ same other frame frame already in the chain. If it is, there is
+ most likely a stack cycle, so we discard it, and mark THIS_FRAME as
+ outermost, with UNWIND_SAME_ID stop reason. Unlike the other
+ validity tests, that compare THIS_FRAME and the next frame, we do
+ this right after creating the previous frame, to avoid ever ending
+ up with two frames with the same id in the frame chain. */
+
+static struct frame_info *
+get_prev_frame_if_no_cycle (struct frame_info *this_frame)
+{
+ struct frame_info *prev_frame;
+ struct cleanup *prev_frame_cleanup;
+
+ prev_frame = get_prev_frame_raw (this_frame);
+
+ /* Don't compute the frame id of the current frame yet. Unwinding
+ the sentinel frame can fail (e.g., if the thread is gone and we
+ can't thus read its registers). If we let the cycle detection
+ code below try to compute a frame ID, then an error thrown from
+ within the frame ID computation would result in the sentinel
+ frame as outermost frame, which is bogus. Instead, we'll compute
+ the current frame's ID lazily in get_frame_id. Note that there's
+ no point in doing cycle detection when there's only one frame, so
+ nothing is lost here. */
+ if (prev_frame->level == 0)
+ return prev_frame;
+
+ /* The cleanup will remove the previous frame that get_prev_frame_raw
+ linked onto THIS_FRAME. */
+ prev_frame_cleanup = make_cleanup (remove_prev_frame, this_frame);
+
+ compute_frame_id (prev_frame);
+ if (!frame_stash_add (prev_frame))
+ {
+ /* Another frame with the same id was already in the stash. We just
+ detected a cycle. */
+ if (frame_debug)
+ {
+ fprintf_unfiltered (gdb_stdlog, "-> ");
+ fprint_frame (gdb_stdlog, NULL);
+ fprintf_unfiltered (gdb_stdlog, " // this frame has same ID }\n");
+ }
+ this_frame->stop_reason = UNWIND_SAME_ID;
+ /* Unlink. */
+ prev_frame->next = NULL;
+ this_frame->prev = NULL;
+ prev_frame = NULL;
+ }
+
+ discard_cleanups (prev_frame_cleanup);
+ return prev_frame;
+}
+
+/* Helper function for get_prev_frame_always, this is called inside a
+ TRY_CATCH block. Return the frame that called THIS_FRAME or NULL if
+ there is no such frame. This may throw an exception. */
static struct frame_info *
-get_prev_frame_1 (struct frame_info *this_frame)
+get_prev_frame_always_1 (struct frame_info *this_frame)
{
- struct frame_id this_id;
struct gdbarch *gdbarch;
gdb_assert (this_frame != NULL);
if (frame_debug)
{
- fprintf_unfiltered (gdb_stdlog, "{ get_prev_frame_1 (this_frame=");
+ fprintf_unfiltered (gdb_stdlog, "{ get_prev_frame_always (this_frame=");
if (this_frame != NULL)
fprintf_unfiltered (gdb_stdlog, "%d", this_frame->level);
else
until we have unwound all the way down to the previous non-inline
frame. */
if (get_frame_type (this_frame) == INLINE_FRAME)
- return get_prev_frame_raw (this_frame);
+ return get_prev_frame_if_no_cycle (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);
- /* 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_eq (this_id, outer_frame_id))
+ if (this_frame->stop_reason != UNWIND_NO_REASON)
{
if (frame_debug)
{
+ enum unwind_stop_reason reason = this_frame->stop_reason;
+
fprintf_unfiltered (gdb_stdlog, "-> ");
fprint_frame (gdb_stdlog, NULL);
- fprintf_unfiltered (gdb_stdlog, " // this ID is NULL }\n");
+ fprintf_unfiltered (gdb_stdlog, " // %s }\n",
+ frame_stop_reason_symbol_string (reason));
}
- this_frame->stop_reason = UNWIND_NULL_ID;
return NULL;
}
See the comment at frame_id_inner for details. */
if (get_frame_type (this_frame) == NORMAL_FRAME
&& this_frame->next->unwind->type == NORMAL_FRAME
- && frame_id_inner (get_frame_arch (this_frame->next), this_id,
+ && frame_id_inner (get_frame_arch (this_frame->next),
+ get_frame_id (this_frame),
get_frame_id (this_frame->next)))
{
CORE_ADDR this_pc_in_block;
/* gcc -fsplit-stack __morestack can continue the stack anywhere. */
this_pc_in_block = get_frame_address_in_block (this_frame);
- morestack_msym = lookup_minimal_symbol_by_pc (this_pc_in_block);
+ morestack_msym = lookup_minimal_symbol_by_pc (this_pc_in_block).minsym;
if (morestack_msym)
- morestack_name = SYMBOL_LINKAGE_NAME (morestack_msym);
+ morestack_name = MSYMBOL_LINKAGE_NAME (morestack_msym);
if (!morestack_name || strcmp (morestack_name, "__morestack") != 0)
{
if (frame_debug)
}
}
- /* 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)))
- {
- if (frame_debug)
- {
- fprintf_unfiltered (gdb_stdlog, "-> ");
- fprint_frame (gdb_stdlog, NULL);
- fprintf_unfiltered (gdb_stdlog, " // this frame has same ID }\n");
- }
- this_frame->stop_reason = UNWIND_SAME_ID;
- return NULL;
- }
-
/* Check that this and the next frame do not unwind the PC register
to the same memory location. If they do, then even though they
have different frame IDs, the new frame will be bogus; two
}
}
- return get_prev_frame_raw (this_frame);
+ return get_prev_frame_if_no_cycle (this_frame);
+}
+
+/* Return a "struct frame_info" corresponding to the frame that called
+ THIS_FRAME. Returns NULL if there is no such frame.
+
+ Unlike get_prev_frame, this function always tries to unwind the
+ frame. */
+
+struct frame_info *
+get_prev_frame_always (struct frame_info *this_frame)
+{
+ struct frame_info *prev_frame = NULL;
+
+ TRY
+ {
+ prev_frame = get_prev_frame_always_1 (this_frame);
+ }
+ CATCH (ex, RETURN_MASK_ERROR)
+ {
+ if (ex.error == MEMORY_ERROR)
+ {
+ this_frame->stop_reason = UNWIND_MEMORY_ERROR;
+ if (ex.message != NULL)
+ {
+ char *stop_string;
+ size_t size;
+
+ /* The error needs to live as long as the frame does.
+ Allocate using stack local STOP_STRING then assign the
+ pointer to the frame, this allows the STOP_STRING on the
+ frame to be of type 'const char *'. */
+ size = strlen (ex.message) + 1;
+ stop_string = (char *) frame_obstack_zalloc (size);
+ memcpy (stop_string, ex.message, size);
+ this_frame->stop_string = stop_string;
+ }
+ prev_frame = NULL;
+ }
+ else
+ throw_exception (ex);
+ }
+ END_CATCH
+
+ return prev_frame;
}
/* Construct a new "struct frame_info" and link it previous to
static int
inside_main_func (struct frame_info *this_frame)
{
- struct minimal_symbol *msymbol;
+ struct bound_minimal_symbol msymbol;
CORE_ADDR maddr;
if (symfile_objfile == 0)
return 0;
msymbol = lookup_minimal_symbol (main_name (), NULL, symfile_objfile);
- if (msymbol == NULL)
+ if (msymbol.minsym == NULL)
return 0;
/* Make certain that the code, and not descriptor, address is
returned. */
maddr = gdbarch_convert_from_func_ptr_addr (get_frame_arch (this_frame),
- SYMBOL_VALUE_ADDRESS (msymbol),
+ BMSYMBOL_VALUE_ADDRESS (msymbol),
¤t_target);
return maddr == get_frame_func (this_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);
+
+ /* If this_frame is the current frame, then compute and stash
+ its frame id prior to fetching and computing the frame id of the
+ previous frame. Otherwise, the cycle detection code in
+ get_prev_frame_if_no_cycle() will not work correctly. When
+ get_frame_id() is called later on, an assertion error will
+ be triggered in the event of a cycle between the current
+ frame and its previous frame. */
+ if (this_frame->level == 0)
+ get_frame_id (this_frame);
+
+ 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 get_prev_frame_1 (this_frame);
+ return get_prev_frame_always (this_frame);
+}
+
+struct frame_id
+get_prev_frame_id_by_id (struct frame_id id)
+{
+ struct frame_id prev_id;
+ struct frame_info *frame;
+
+ frame = frame_find_by_id (id);
+
+ if (frame != NULL)
+ prev_id = get_frame_id (get_prev_frame (frame));
+ else
+ prev_id = null_frame_id;
+
+ return prev_id;
}
CORE_ADDR
return frame_unwind_pc (frame->next);
}
+int
+get_frame_pc_if_available (struct frame_info *frame, CORE_ADDR *pc)
+{
+
+ gdb_assert (frame->next != NULL);
+
+ TRY
+ {
+ *pc = frame_unwind_pc (frame->next);
+ }
+ CATCH (ex, RETURN_MASK_ERROR)
+ {
+ if (ex.error == NOT_AVAILABLE_ERROR)
+ return 0;
+ else
+ throw_exception (ex);
+ }
+ END_CATCH
+
+ return 1;
+}
+
/* Return an address that falls within THIS_FRAME's code block. */
CORE_ADDR
while (get_frame_type (next_frame) == INLINE_FRAME)
next_frame = next_frame->next;
- if (get_frame_type (next_frame) == NORMAL_FRAME
+ if ((get_frame_type (next_frame) == NORMAL_FRAME
+ || get_frame_type (next_frame) == TAILCALL_FRAME)
&& (get_frame_type (this_frame) == NORMAL_FRAME
+ || get_frame_type (this_frame) == TAILCALL_FRAME
|| get_frame_type (this_frame) == INLINE_FRAME))
return pc - 1;
return pc;
}
+int
+get_frame_address_in_block_if_available (struct frame_info *this_frame,
+ CORE_ADDR *pc)
+{
+
+ TRY
+ {
+ *pc = get_frame_address_in_block (this_frame);
+ }
+ CATCH (ex, RETURN_MASK_ERROR)
+ {
+ if (ex.error == NOT_AVAILABLE_ERROR)
+ return 0;
+ throw_exception (ex);
+ }
+ END_CATCH
+
+ 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)
{
- sal->symtab = SYMBOL_SYMTAB (sym);
+ sal->symtab = symbol_symtab (sym);
sal->line = SYMBOL_LINE (sym);
}
else
we can't do much better. */
sal->pc = get_frame_pc (frame);
+ sal->pspace = get_frame_program_space (frame);
+
return;
}
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
struct gdbarch *
frame_unwind_caller_arch (struct frame_info *next_frame)
{
- return frame_unwind_arch (skip_inlined_frames (next_frame));
+ next_frame = skip_artificial_frames (next_frame);
+
+ /* We must have a non-artificial frame. The caller is supposed to check
+ the result of frame_unwind_caller_id (), which returns NULL_FRAME_ID
+ in this case. */
+ gdb_assert (next_frame != NULL);
+
+ return frame_unwind_arch (next_frame);
+}
+
+/* Gets the language of FRAME. */
+
+enum language
+get_frame_language (struct frame_info *frame)
+{
+ CORE_ADDR pc = 0;
+ int pc_p = 0;
+
+ gdb_assert (frame!= NULL);
+
+ /* We determine the current frame language by looking up its
+ associated symtab. To retrieve this symtab, we use 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(), it provides us with
+ a PC that is guaranteed to be inside the frame's code
+ block. */
+
+ TRY
+ {
+ pc = get_frame_address_in_block (frame);
+ pc_p = 1;
+ }
+ CATCH (ex, RETURN_MASK_ERROR)
+ {
+ if (ex.error != NOT_AVAILABLE_ERROR)
+ throw_exception (ex);
+ }
+ END_CATCH
+
+ if (pc_p)
+ {
+ struct compunit_symtab *cust = find_pc_compunit_symtab (pc);
+
+ if (cust != NULL)
+ return compunit_language (cust);
+ }
+
+ return language_unknown;
}
/* Stack pointer methods. */
enum unwind_stop_reason
get_frame_unwind_stop_reason (struct frame_info *frame)
{
- /* If we haven't tried to unwind past this point yet, then assume
- that unwinding would succeed. */
- if (frame->prev_p == 0)
- return UNWIND_NO_REASON;
+ /* Fill-in STOP_REASON. */
+ get_prev_frame_always (frame);
+ gdb_assert (frame->prev_p);
- /* 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)
+unwind_stop_reason_to_string (enum unwind_stop_reason reason)
{
switch (reason)
{
- case UNWIND_NULL_ID:
- return _("unwinder did not report frame ID");
+#define SET(name, description) \
+ case name: return _(description);
+#include "unwind_stop_reasons.def"
+#undef SET
+
+ default:
+ internal_error (__FILE__, __LINE__,
+ "Invalid frame stop reason");
+ }
+}
+
+const char *
+frame_stop_reason_string (struct frame_info *fi)
+{
+ gdb_assert (fi->prev_p);
+ gdb_assert (fi->prev == NULL);
+
+ /* Return the specific string if we have one. */
+ if (fi->stop_string != NULL)
+ return fi->stop_string;
- case UNWIND_INNER_ID:
- return _("previous frame inner to this frame (corrupt stack?)");
+ /* Return the generic string if we have nothing better. */
+ return unwind_stop_reason_to_string (fi->stop_reason);
+}
- case UNWIND_SAME_ID:
- return _("previous frame identical to this frame (corrupt stack?)");
+/* Return the enum symbol name of REASON as a string, to use in debug
+ output. */
- case UNWIND_NO_SAVED_PC:
- return _("frame did not save the PC");
+static const char *
+frame_stop_reason_symbol_string (enum unwind_stop_reason reason)
+{
+ switch (reason)
+ {
+#define SET(name, description) \
+ case name: return #name;
+#include "unwind_stop_reasons.def"
+#undef SET
- case UNWIND_NO_REASON:
- case UNWIND_FIRST_ERROR:
default:
internal_error (__FILE__, __LINE__,
"Invalid frame stop reason");
static void
frame_cleanup_after_sniffer (void *arg)
{
- struct frame_info *frame = arg;
+ struct frame_info *frame = (struct frame_info *) arg;
/* The sniffer should not allocate a prologue cache if it did not
match this frame. */
static void
set_backtrace_cmd (char *args, int from_tty)
{
- help_list (set_backtrace_cmdlist, "set backtrace ", -1, gdb_stdout);
+ help_list (set_backtrace_cmdlist, "set backtrace ", all_commands,
+ gdb_stdout);
}
static void
{
obstack_init (&frame_cache_obstack);
+ frame_stash_create ();
+
observer_attach_target_changed (frame_observer_target_changed);
add_prefix_cmd ("backtrace", class_maintenance, set_backtrace_cmd, _("\
&set_backtrace_cmdlist,
&show_backtrace_cmdlist);
- add_setshow_integer_cmd ("limit", class_obscure,
- &backtrace_limit, _("\
+ add_setshow_uinteger_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);
+Literal \"unlimited\" or zero means no limit."),
+ NULL,
+ show_backtrace_limit,
+ &set_backtrace_cmdlist,
+ &show_backtrace_cmdlist);
- /* Debug this files internals. */
- add_setshow_zinteger_cmd ("frame", class_maintenance, &frame_debug, _("\
+ /* Debug this files internals. */
+ add_setshow_zuinteger_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);
+ NULL,
+ show_frame_debug,
+ &setdebuglist, &showdebuglist);
}
projects / deliverable / binutils-gdb.git / blobdiff