/* 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 Free Software Foundation, Inc.
+ 2002, 2003, 2004, 2007, 2008, 2009, 2010 Free Software Foundation, Inc.
This file is part of GDB.
moment leave this as speculation. */
int level;
+ /* The frame's program space. */
+ struct program_space *pspace;
+
+ /* The frame's address space. */
+ struct address_space *aspace;
+
/* 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
enum unwind_stop_reason stop_reason;
};
+/* A frame stash used to speed up frame lookups. */
+
+/* We currently only stash one frame at a time, as this seems to be
+ sufficient for now. */
+static struct frame_info *frame_stash = NULL;
+
+/* Add the following FRAME to the frame stash. */
+
+static void
+frame_stash_add (struct frame_info *frame)
+{
+ frame_stash = frame;
+}
+
+/* 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;
+
+ return NULL;
+}
+
+/* Invalidate the frame stash by removing all entries in it. */
+
+static void
+frame_stash_invalidate (void)
+{
+ frame_stash = NULL;
+}
+
/* Flag to control debugging. */
int frame_debug;
get_frame_id (struct frame_info *fi)
{
if (fi == NULL)
- {
- return null_frame_id;
- }
+ return null_frame_id;
+
if (!fi->this_id.p)
{
if (frame_debug)
if (fi->unwind == NULL)
fi->unwind = 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, " }\n");
}
}
+
+ frame_stash_add (fi);
+
return fi->this_id.value;
}
}
const struct frame_id null_frame_id; /* All zeros. */
+const struct frame_id outer_frame_id = { 0, 0, 0, 0, 0, 1, 0 };
struct frame_id
frame_id_build_special (CORE_ADDR stack_addr, CORE_ADDR code_addr,
int p;
/* The frame is valid iff it has a valid stack address. */
p = l.stack_addr_p;
+ /* outer_frame_id is also valid. */
+ if (!p && memcmp (&l, &outer_frame_id, sizeof (l)) == 0)
+ p = 1;
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_p || !r.stack_addr_p)
+ if (!l.stack_addr_p && l.special_addr_p && !r.stack_addr_p && 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)
/* 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;
if (!frame_id_p (id))
return NULL;
+ /* 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)
+ and get_prev_frame performs a series of checks that are relatively
+ expensive). This optimization is particularly useful when this function
+ is called from another function (such as value_fetch_lazy, case
+ VALUE_LVAL (val) == lval_register) which already loops over all frames,
+ making the overall behavior O(n^2). */
+ frame = frame_stash_find (id);
+ if (frame)
+ return frame;
+
for (frame = get_current_frame (); ; frame = prev_frame)
{
struct frame_id this = get_frame_id (frame);
this_frame->prev_pc.p = 1;
if (frame_debug)
fprintf_unfiltered (gdb_stdlog,
- "{ frame_unwind_caller_pc (this_frame=%d) -> 0x%s }\n",
+ "{ frame_unwind_caller_pc (this_frame=%d) -> %s }\n",
this_frame->level,
hex_string (this_frame->prev_pc.value));
}
struct regcache *
frame_save_as_regcache (struct frame_info *this_frame)
{
- struct regcache *regcache = regcache_xmalloc (get_frame_arch (this_frame));
+ struct address_space *aspace = get_frame_address_space (this_frame);
+ struct regcache *regcache = regcache_xmalloc (get_frame_arch (this_frame),
+ aspace);
struct cleanup *cleanups = make_cleanup_regcache_xfree (regcache);
regcache_save (regcache, do_frame_register_read, this_frame);
discard_cleanups (cleanups);
/* Create a sentinel frame. */
static struct frame_info *
-create_sentinel_frame (struct regcache *regcache)
+create_sentinel_frame (struct program_space *pspace, struct regcache *regcache)
{
struct frame_info *frame = FRAME_OBSTACK_ZALLOC (struct frame_info);
frame->level = -1;
+ frame->pspace = pspace;
+ frame->aspace = get_regcache_aspace (regcache);
/* Explicitly initialize the sentinel frame's cache. Provide it
with the underlying regcache. In the future additional
information, such as the frame's thread will be added. */
if (current_frame == NULL)
{
struct frame_info *sentinel_frame =
- create_sentinel_frame (get_current_regcache ());
+ create_sentinel_frame (current_program_space, get_current_regcache ());
if (catch_exceptions (uiout, unwind_to_current_frame, sentinel_frame,
RETURN_MASK_ERROR) != 0)
{
fi = FRAME_OBSTACK_ZALLOC (struct frame_info);
- fi->next = create_sentinel_frame (get_current_regcache ());
+ fi->next = create_sentinel_frame (current_program_space, get_current_regcache ());
/* Set/update this frame's cached PC value, found in the next frame.
Do this before looking for this frame's unwinder. A sniffer is
fi->next->prev_pc.value = pc;
fi->next->prev_pc.p = 1;
+ /* We currently assume that frame chain's can't cross spaces. */
+ fi->pspace = fi->next->pspace;
+ fi->aspace = fi->next->aspace;
+
/* Select/initialize both the unwind function and the frame's type
based on the PC. */
fi->unwind = frame_unwind_find_by_frame (fi, &fi->prologue_cache);
current_frame = NULL; /* Invalidate cache */
select_frame (NULL);
+ frame_stash_invalidate ();
if (frame_debug)
fprintf_unfiltered (gdb_stdlog, "{ reinit_frame_cache () }\n");
}
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 (this_frame->level >= 0 && frame_id_eq (this_id, outer_frame_id))
{
if (frame_debug)
{
prev_frame = FRAME_OBSTACK_ZALLOC (struct frame_info);
prev_frame->level = this_frame->level + 1;
+ /* For now, assume we don't have frame chains crossing address
+ spaces. */
+ prev_frame->pspace = this_frame->pspace;
+ prev_frame->aspace = this_frame->aspace;
+
/* Don't yet compute ->unwind (and hence ->type). It is computed
on-demand in get_frame_type, frame_register_unwind, and
get_frame_id. */
static int
inside_entry_func (struct frame_info *this_frame)
{
- return (get_frame_func (this_frame) == entry_point_address ());
+ CORE_ADDR entry_point;
+
+ if (!entry_point_address_query (&entry_point))
+ return 0;
+
+ return get_frame_func (this_frame) == entry_point;
}
/* Return a structure containing various interesting information about
return frame->unwind->type;
}
+struct program_space *
+get_frame_program_space (struct frame_info *frame)
+{
+ return frame->pspace;
+}
+
+struct program_space *
+frame_unwind_program_space (struct frame_info *this_frame)
+{
+ gdb_assert (this_frame);
+
+ /* This is really a placeholder to keep the API consistent --- we
+ assume for now that we don't have frame chains crossing
+ spaces. */
+ return this_frame->pspace;
+}
+
+struct address_space *
+get_frame_address_space (struct frame_info *frame)
+{
+ return frame->aspace;
+}
+
/* Memory access methods. */
void
projects / deliverable / binutils-gdb.git / blobdiff