/* 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 Free Software Foundation, Inc.
+ 2002, 2003, 2004, 2007, 2008, 2009, 2010, 2011
+ Free Software Foundation, Inc.
This file is part of GDB.
#include "observer.h"
#include "objfiles.h"
#include "exceptions.h"
+#include "gdbthread.h"
+#include "block.h"
+#include "inline-frame.h"
+#include "tracepoint.h"
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);
/* We keep a cache of stack frames, each of which is a "struct
frame_info". The innermost one gets allocated (in
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
void *prologue_cache;
const struct frame_unwind *unwind;
+ /* Cached copy of the previous frame's architecture. */
+ struct
+ {
+ int p;
+ struct gdbarch *arch;
+ } prev_arch;
+
/* Cached copy of the previous frame's resume address. */
struct {
int p;
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. */
-static int frame_debug;
+int frame_debug;
static void
show_frame_debug (struct ui_file *file, int from_tty,
struct cmd_list_element *c, const char *value)
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"),
+ fprintf_filtered (file,
+ _("Whether backtraces should "
+ "continue past \"main\" is %s.\n"),
value);
}
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"),
+ fprintf_filtered (file, _("Whether backtraces should continue past the "
+ "entry point of a program is %s.\n"),
value);
}
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"),
+ fprintf_filtered (file,
+ _("An upper bound on the number "
+ "of backtrace levels is %s.\n"),
value);
}
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));
+ fprintf_unfiltered (file, "%s=%s", name, hex_string (addr));
else
fprintf_unfiltered (file, "!%s", name);
}
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);
fprintf_unfiltered (file, "}");
}
case DUMMY_FRAME:
fprintf_unfiltered (file, "DUMMY_FRAME");
return;
+ case INLINE_FRAME:
+ fprintf_unfiltered (file, "INLINE_FRAME");
+ return;
+ case SENTINEL_FRAME:
+ fprintf_unfiltered (file, "SENTINEL_FRAME");
+ return;
case SIGTRAMP_FRAME:
fprintf_unfiltered (file, "SIGTRAMP_FRAME");
return;
+ case ARCH_FRAME:
+ fprintf_unfiltered (file, "ARCH_FRAME");
+ return;
default:
fprintf_unfiltered (file, "<unknown type>");
return;
fprintf_unfiltered (file, ",");
fprintf_unfiltered (file, "pc=");
if (fi->next != NULL && fi->next->prev_pc.p)
- fprintf_unfiltered (file, "0x%s", paddr_nz (fi->next->prev_pc.value));
+ fprintf_unfiltered (file, "%s", hex_string (fi->next->prev_pc.value));
else
fprintf_unfiltered (file, "<unknown>");
fprintf_unfiltered (file, ",");
fprintf_unfiltered (file, ",");
fprintf_unfiltered (file, "func=");
if (fi->next != NULL && fi->next->prev_func.p)
- fprintf_unfiltered (file, "0x%s", paddr_nz (fi->next->prev_func.addr));
+ fprintf_unfiltered (file, "%s", hex_string (fi->next->prev_func.addr));
else
fprintf_unfiltered (file, "<unknown>");
fprintf_unfiltered (file, "}");
}
+/* Given FRAME, return the enclosing normal frame for inlined
+ function frames. Otherwise return the original frame. */
+
+static struct frame_info *
+skip_inlined_frames (struct frame_info *frame)
+{
+ while (get_frame_type (frame) == INLINE_FRAME)
+ frame = get_prev_frame (frame);
+
+ return frame;
+}
+
/* Return a frame uniq ID that can be used to, later, re-find the
frame. */
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)
fi->level);
/* Find the unwinder. */
if (fi->unwind == NULL)
- fi->unwind = frame_unwind_find_by_frame (fi->next,
- &fi->prologue_cache);
+ frame_unwind_find_by_frame (fi, &fi->prologue_cache);
/* Find THIS frame's ID. */
- fi->unwind->this_id (fi->next, &fi->prologue_cache, &fi->this_id.value);
+ /* 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;
}
struct frame_id
-frame_unwind_id (struct frame_info *next_frame)
+get_stack_frame_id (struct frame_info *next_frame)
+{
+ return get_frame_id (skip_inlined_frames (next_frame));
+}
+
+struct frame_id
+frame_unwind_caller_id (struct frame_info *next_frame)
{
- /* Use prev_frame, and not get_prev_frame. The latter will truncate
+ 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. */
- return get_frame_id (get_prev_frame_1 (next_frame));
+
+ next_frame = skip_inlined_frames (next_frame);
+ this_frame = get_prev_frame_1 (next_frame);
+ if (this_frame)
+ return get_frame_id (skip_inlined_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 };
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;
frame_id_build (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.code_addr = code_addr;
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 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=");
return p;
}
+int
+frame_id_inlined_p (struct frame_id l)
+{
+ if (!frame_id_p (l))
+ return 0;
+
+ return (l.inline_depth != 0);
+}
+
int
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;
else if (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)
- /* 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. */
+ else if (l.code_addr_p && r.code_addr_p && l.code_addr != r.code_addr)
+ /* An invalid code addr is a wild card. 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.special_addr == r.special_addr)
+ else if (l.special_addr_p && r.special_addr_p
+ && l.special_addr != r.special_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. */
+ eq = 0;
+ else
/* Frames are equal. */
eq = 1;
- else
- /* No luck. */
- eq = 0;
+
if (frame_debug)
{
fprintf_unfiltered (gdb_stdlog, "{ frame_id_eq (l=");
return eq;
}
-int
-frame_id_inner (struct frame_id l, struct frame_id r)
+/* Safety net to check whether frame ID L should be inner to
+ frame ID R, according to their stack addresses.
+
+ This method cannot be used to compare arbitrary frames, as the
+ ranges of valid stack addresses may be discontiguous (e.g. due
+ to sigaltstack).
+
+ However, it can be used as safety net to discover invalid frame
+ 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
+ address of THIS.
+
+ Therefore, if frame_id_inner (THIS, NEXT) holds, some unwind
+ error has occurred.
+
+ * If NEXT and THIS have different stack addresses, no other frame
+ in the frame chain may have a stack address in between.
+
+ Therefore, if frame_id_inner (TEST, THIS) holds, but
+ frame_id_inner (TEST, NEXT) does not hold, TEST cannot refer
+ to a valid frame in the frame chain.
+
+ The sanity checks above cannot be performed when a SIGTRAMP frame
+ 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
+ a stack overflow strategy that cause the handler to be run on a
+ different stack. */
+
+static int
+frame_id_inner (struct gdbarch *gdbarch, struct frame_id l, struct frame_id r)
{
int inner;
+
if (!l.stack_addr_p || !r.stack_addr_p)
/* Like NaN, any operation involving an invalid ID always fails. */
inner = 0;
+ else if (l.inline_depth > r.inline_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;
+
+ gdb_assert (l.code_addr_p && r.code_addr_p);
+
+ lb = block_for_pc (l.code_addr);
+ rb = block_for_pc (r.code_addr);
+
+ if (lb == NULL || rb == NULL)
+ /* Something's gone wrong. */
+ inner = 0;
+ else
+ /* This will return true if LB and RB are the same block, or
+ if the block with the smaller depth lexically encloses the
+ block with the greater depth. */
+ inner = contained_in (lb, rb);
+ }
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 and/or .special address). */
- inner = gdbarch_inner_than (current_gdbarch, l.stack_addr, r.stack_addr);
+ inner = gdbarch_inner_than (gdbarch, l.stack_addr, r.stack_addr);
if (frame_debug)
{
fprintf_unfiltered (gdb_stdlog, "{ frame_id_inner (l=");
struct frame_info *
frame_find_by_id (struct frame_id id)
{
- struct frame_info *frame;
+ struct frame_info *frame, *prev_frame;
/* ZERO denotes the null frame, let the caller decide what to do
about it. Should it instead return get_current_frame()? */
if (!frame_id_p (id))
return NULL;
- for (frame = get_current_frame ();
- frame != NULL;
- frame = get_prev_frame (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)
+ 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);
+
if (frame_id_eq (id, this))
/* An exact match. */
return frame;
- if (frame_id_inner (id, this))
- /* Gone to far. */
+
+ prev_frame = get_prev_frame (frame);
+ if (!prev_frame)
+ return NULL;
+
+ /* As a safety net to avoid unnecessary backtracing while trying
+ to find an invalid ID, we check for a common situation where
+ we can detect from comparing stack addresses that no other
+ 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 (prev_frame), id,
+ get_frame_id (prev_frame)))
return NULL;
- /* 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. */
}
return NULL;
}
-CORE_ADDR
-frame_pc_unwind (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 (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 (get_frame_arch (this_frame)))
+ 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 (get_frame_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_pc_unwind (this_frame=%d) -> 0x%s }\n",
- this_frame->level,
- paddr_nz (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
-frame_func_unwind (struct frame_info *fi, enum frame_type this_type)
+frame_unwind_caller_pc (struct frame_info *this_frame)
+{
+ return frame_unwind_pc (skip_inlined_frames (this_frame));
+}
+
+int
+frame_unwind_caller_pc_if_available (struct frame_info *this_frame,
+ CORE_ADDR *pc)
{
- if (!fi->prev_func.p)
+ 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 = frame_unwind_address_in_block (fi, this_type);
- fi->prev_func.p = 1;
- 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",
- fi->level, paddr_nz (fi->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 fi->prev_func.addr;
}
CORE_ADDR
-get_frame_func (struct frame_info *fi)
+get_frame_func (struct frame_info *this_frame)
{
- return frame_func_unwind (fi->next, get_frame_type (fi));
+ CORE_ADDR pc;
+
+ if (!get_frame_func_if_available (this_frame, &pc))
+ throw_error (NOT_AVAILABLE_ERROR, _("PC not available"));
+
+ return pc;
}
-static int
+static enum register_status
do_frame_register_read (void *src, int regnum, gdb_byte *buf)
{
- frame_register_read (src, regnum, buf);
- return 1;
+ if (!frame_register_read (src, regnum, buf))
+ return REG_UNAVAILABLE;
+ else
+ return REG_VALID;
}
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);
return regcache;
struct regcache *scratch;
struct cleanup *cleanups;
+ if (get_frame_type (this_frame) == DUMMY_FRAME)
+ {
+ /* 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));
+ return;
+ }
+
/* Ensure that we have a frame to pop to. */
prev_frame = get_prev_frame_1 (this_frame);
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 frame_unwind_cache *cache;
-
- if (frame_debug)
- {
- fprintf_unfiltered (gdb_stdlog, "\
-{ frame_register_unwind (frame=%d,regnum=%d(%s),...) ",
- frame->level, regnum,
- frame_map_regnum_to_name (frame, regnum));
- }
+ struct value *value;
/* 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); */
- /* 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 a frame, there is some pretty busted code as it should have
- detected the problem before calling here. */
- gdb_assert (frame != NULL);
+ value = frame_unwind_register_value (frame, regnum);
- /* Find the unwinder. */
- if (frame->unwind == NULL)
- frame->unwind = frame_unwind_find_by_frame (frame->next,
- &frame->prologue_cache);
+ gdb_assert (value != NULL);
- /* Ask this frame to unwind its register. See comment in
- "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);
+ *optimizedp = value_optimized_out (value);
+ *unavailablep = !value_entirely_available (value);
+ *lvalp = VALUE_LVAL (value);
+ *addrp = value_address (value);
+ *realnump = VALUE_REGNUM (value);
- if (frame_debug)
+ if (bufferp)
{
- fprintf_unfiltered (gdb_stdlog, "->");
- fprintf_unfiltered (gdb_stdlog, " *optimizedp=%d", (*optimizedp));
- fprintf_unfiltered (gdb_stdlog, " *lvalp=%d", (int) (*lvalp));
- fprintf_unfiltered (gdb_stdlog, " *addrp=0x%s", paddr_nz ((*addrp)));
- fprintf_unfiltered (gdb_stdlog, " *bufferp=");
- if (bufferp == NULL)
- fprintf_unfiltered (gdb_stdlog, "<NULL>");
+ if (!*optimizedp && !*unavailablep)
+ memcpy (bufferp, value_contents_all (value),
+ TYPE_LENGTH (value_type (value)));
else
- {
- int i;
- const unsigned char *buf = bufferp;
- fprintf_unfiltered (gdb_stdlog, "[");
- for (i = 0; i < register_size (get_frame_arch (frame), regnum); i++)
- fprintf_unfiltered (gdb_stdlog, "%02x", buf[i]);
- fprintf_unfiltered (gdb_stdlog, "]");
- }
- fprintf_unfiltered (gdb_stdlog, " }\n");
+ memset (bufferp, 0, TYPE_LENGTH (value_type (value)));
}
+
+ /* Dispose of the new value. This prevents watchpoints from
+ trying to watch the saved frame pointer. */
+ release_value (value);
+ value_free (value);
}
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
frame_unwind_register (frame->next, regnum, buf);
}
+struct value *
+frame_unwind_register_value (struct frame_info *frame, int regnum)
+{
+ struct gdbarch *gdbarch;
+ struct value *value;
+
+ gdb_assert (frame != NULL);
+ gdbarch = frame_unwind_arch (frame);
+
+ if (frame_debug)
+ {
+ fprintf_unfiltered (gdb_stdlog,
+ "{ frame_unwind_register_value "
+ "(frame=%d,regnum=%d(%s),...) ",
+ frame->level, regnum,
+ user_reg_map_regnum_to_name (gdbarch, regnum));
+ }
+
+ /* Find the unwinder. */
+ if (frame->unwind == NULL)
+ frame_unwind_find_by_frame (frame, &frame->prologue_cache);
+
+ /* Ask this frame to unwind its register. */
+ value = frame->unwind->prev_register (frame, &frame->prologue_cache, regnum);
+
+ if (frame_debug)
+ {
+ fprintf_unfiltered (gdb_stdlog, "->");
+ if (value_optimized_out (value))
+ fprintf_unfiltered (gdb_stdlog, " optimized out");
+ else
+ {
+ if (VALUE_LVAL (value) == lval_register)
+ fprintf_unfiltered (gdb_stdlog, " register=%d",
+ VALUE_REGNUM (value));
+ else if (VALUE_LVAL (value) == lval_memory)
+ fprintf_unfiltered (gdb_stdlog, " address=%s",
+ paddress (gdbarch,
+ value_address (value)));
+ else
+ fprintf_unfiltered (gdb_stdlog, " computed");
+
+ if (value_lazy (value))
+ fprintf_unfiltered (gdb_stdlog, " lazy");
+ else
+ {
+ int i;
+ const gdb_byte *buf = value_contents (value);
+
+ fprintf_unfiltered (gdb_stdlog, " bytes=");
+ fprintf_unfiltered (gdb_stdlog, "[");
+ for (i = 0; i < register_size (gdbarch, regnum); i++)
+ fprintf_unfiltered (gdb_stdlog, "%02x", buf[i]);
+ fprintf_unfiltered (gdb_stdlog, "]");
+ }
+ }
+
+ fprintf_unfiltered (gdb_stdlog, " }\n");
+ }
+
+ return value;
+}
+
+struct value *
+get_frame_register_value (struct frame_info *frame, int regnum)
+{
+ return frame_unwind_register_value (frame->next, regnum);
+}
+
LONGEST
frame_unwind_register_signed (struct frame_info *frame, int regnum)
{
+ struct gdbarch *gdbarch = frame_unwind_arch (frame);
+ enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
+ int size = register_size (gdbarch, regnum);
gdb_byte buf[MAX_REGISTER_SIZE];
+
frame_unwind_register (frame, regnum, buf);
- return extract_signed_integer (buf, register_size (get_frame_arch (frame),
- regnum));
+ return extract_signed_integer (buf, size, byte_order);
}
LONGEST
ULONGEST
frame_unwind_register_unsigned (struct frame_info *frame, int regnum)
{
+ struct gdbarch *gdbarch = frame_unwind_arch (frame);
+ enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
+ int size = register_size (gdbarch, regnum);
gdb_byte buf[MAX_REGISTER_SIZE];
+
frame_unwind_register (frame, regnum, buf);
- return extract_unsigned_integer (buf, register_size (get_frame_arch (frame),
- regnum));
+ return extract_unsigned_integer (buf, size, byte_order);
}
ULONGEST
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)
/* 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));
break;
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);
- return !optimized;
+ frame_register (frame, regnum, &optimized, &unavailable,
+ &lval, &addr, &realnum, myaddr);
+
+ 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;
+ int maxsize;
+ int numregs;
/* Skip registers wholly inside of OFFSET. */
while (offset >= register_size (gdbarch, regnum))
regnum++;
}
+ /* Ensure that we will not read beyond the end of the register file.
+ This can only ever happen if the debug information is bad. */
+ maxsize = -offset;
+ numregs = gdbarch_num_regs (gdbarch) + gdbarch_num_pseudo_regs (gdbarch);
+ for (i = regnum; i < numregs; i++)
+ {
+ int thissize = register_size (gdbarch, i);
+
+ if (thissize == 0)
+ break; /* This register is not available on this architecture. */
+ maxsize += thissize;
+ }
+ if (len > maxsize)
+ error (_("Bad debug information detected: "
+ "Attempt to read %d bytes from registers."), len);
+
/* 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))
+ 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];
- if (!frame_register_read (frame, regnum, buf))
+ enum lval_type lval;
+ CORE_ADDR addr;
+ int realnum;
+
+ 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;
}
while (len > 0)
{
int curr_len = register_size (gdbarch, regnum) - offset;
+
if (curr_len > len)
curr_len = len;
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);
}
}
-/* Map between a frame register number and its name. A frame register
- space is a superset of the cooked register space --- it also
- includes builtin registers. */
-
-int
-frame_map_name_to_regnum (struct frame_info *frame, const char *name, int len)
-{
- return user_reg_map_name_to_regnum (get_frame_arch (frame), name, len);
-}
-
-const char *
-frame_map_regnum_to_name (struct frame_info *frame, int regnum)
-{
- return user_reg_map_regnum_to_name (get_frame_arch (frame), regnum);
-}
-
/* 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. */
frame->prologue_cache = sentinel_frame_cache (regcache);
/* For the moment there is only one sentinel frame implementation. */
- frame->unwind = sentinel_frame_unwind;
+ frame->unwind = &sentinel_frame_unwind;
/* 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;
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;
frame_obstack_zalloc (unsigned long size)
{
void *data = obstack_alloc (&frame_cache_obstack, size);
+
memset (data, 0, size);
return data;
}
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)
error (_("No stack."));
if (!target_has_memory)
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."));
+ }
+
if (current_frame == NULL)
{
struct frame_info *sentinel_frame =
- create_sentinel_frame (get_current_regcache ());
- if (catch_exceptions (uiout, unwind_to_current_frame, sentinel_frame,
- RETURN_MASK_ERROR) != 0)
+ create_sentinel_frame (current_program_space, get_current_regcache ());
+ if (catch_exceptions (current_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. */
static struct frame_info *selected_frame;
+int
+has_stack_frames (void)
+{
+ 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;
+
+ /* 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;
+
+ return 1;
+}
+
/* 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. */
{
if (selected_frame == NULL)
{
- if (message != NULL && (!target_has_registers
- || !target_has_stack
- || !target_has_memory))
+ if (message != NULL && !has_stack_frames ())
error (("%s"), message);
/* Hey! Don't trust this. It should really be re-finding the
last selected frame of the currently selected thread. This,
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(). */
struct frame_info *
deprecated_safe_get_selected_frame (void)
{
- if (!target_has_registers || !target_has_stack || !target_has_memory)
+ if (!has_stack_frames ())
return NULL;
return get_selected_frame (NULL);
}
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. */
if (frame_debug)
{
fprintf_unfiltered (gdb_stdlog,
- "{ create_new_frame (addr=0x%s, pc=0x%s) ",
- paddr_nz (addr), paddr_nz (pc));
+ "{ create_new_frame (addr=%s, pc=%s) ",
+ hex_string (addr), hex_string (pc));
}
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
+ 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;
+
+ /* 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->next, &fi->prologue_cache);
+ frame_unwind_find_by_frame (fi, &fi->prologue_cache);
fi->this_id.p = 1;
- deprecated_update_frame_base_hack (fi, addr);
- deprecated_update_frame_pc_hack (fi, pc);
+ fi->this_id.value = frame_id_build (addr, pc);
if (frame_debug)
{
/* Observer for the target_changed event. */
-void
+static void
frame_observer_target_changed (struct target_ops *target)
{
reinit_frame_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)
+ annotate_frames_invalid ();
+
current_frame = NULL; /* Invalidate cache */
select_frame (NULL);
- annotate_frames_invalid ();
+ frame_stash_invalidate ();
if (frame_debug)
fprintf_unfiltered (gdb_stdlog, "{ reinit_frame_cache () }\n");
}
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;
static struct frame_info *
get_prev_frame_1 (struct frame_info *this_frame)
{
- struct frame_info *prev_frame;
struct frame_id this_id;
struct gdbarch *gdbarch;
}
return this_frame->prev;
}
+
+ /* If the frame unwinder hasn't been selected yet, we must do so
+ before setting prev_p; otherwise the check for misbehaved
+ sniffers will think that this frame's sniffer tried to unwind
+ further (see frame_cleanup_after_sniffer). */
+ if (this_frame->unwind == NULL)
+ frame_unwind_find_by_frame (this_frame, &this_frame->prologue_cache);
+
this_frame->prev_p = 1;
this_frame->stop_reason = UNWIND_NO_REASON;
+ /* If we are unwinding from an inline frame, all of the below tests
+ were already performed when we unwound from the next non-inline
+ frame. We must skip them, since we can not get THIS_FRAME's ID
+ 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);
+
+ /* 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. */
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)
{
/* 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 check is valid only if this frame and the next frame are NORMAL.
+ 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,
+ get_frame_id (this_frame->next)))
{
- if (frame_debug)
+ CORE_ADDR this_pc_in_block;
+ struct minimal_symbol *morestack_msym;
+ const char *morestack_name = NULL;
+
+ /* 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);
+ if (morestack_msym)
+ morestack_name = SYMBOL_LINKAGE_NAME (morestack_msym);
+ if (!morestack_name || strcmp (morestack_name, "__morestack") != 0)
{
- fprintf_unfiltered (gdb_stdlog, "-> ");
- fprint_frame (gdb_stdlog, NULL);
- fprintf_unfiltered (gdb_stdlog, " // this frame ID is inner }\n");
+ if (frame_debug)
+ {
+ fprintf_unfiltered (gdb_stdlog, "-> ");
+ fprint_frame (gdb_stdlog, NULL);
+ fprintf_unfiltered (gdb_stdlog,
+ " // this frame ID is inner }\n");
+ }
+ this_frame->stop_reason = UNWIND_INNER_ID;
+ return NULL;
}
- this_frame->stop_reason = UNWIND_INNER_ID;
- return NULL;
}
/* Check that this and the next frame are not identical. If they
if (this_frame->level > 0
&& gdbarch_pc_regnum (gdbarch) >= 0
&& get_frame_type (this_frame) == NORMAL_FRAME
- && get_frame_type (this_frame->next) == NORMAL_FRAME)
+ && (get_frame_type (this_frame->next) == NORMAL_FRAME
+ || get_frame_type (this_frame->next) == INLINE_FRAME))
{
int optimized, realnum, nrealnum;
enum lval_type lval, nlval;
}
}
+ return get_prev_frame_raw (this_frame);
+}
+
+/* Construct a new "struct frame_info" and link it previous to
+ this_frame. */
+
+static struct frame_info *
+get_prev_frame_raw (struct frame_info *this_frame)
+{
+ struct frame_info *prev_frame;
+
/* 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
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. */
/* Debug routine to print a NULL frame being returned. */
static void
-frame_debug_got_null_frame (struct ui_file *file,
- struct frame_info *this_frame,
+frame_debug_got_null_frame (struct frame_info *this_frame,
const char *reason)
{
if (frame_debug)
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
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
- caller should have previously obtained a valid frame using
- get_selected_frame() and then called this code - only possibility
- I can think of is code behaving badly.
-
- NOTE: cagney/2003-01-10: Talk about code behaving badly. Check
- block_innermost_frame(). It does the sequence: frame = NULL;
- 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 in
- block_innermost_frame() is, when the target has no state
- (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
- get_prev_frame(). This is a guess mind. */
- if (this_frame == NULL)
- {
- /* NOTE: cagney/2002-11-09: There was a code segment here that
- would error out when CURRENT_FRAME was NULL. The comment
- that went with it made the claim ...
-
- ``This screws value_of_variable, which just wants a nice
- clean NULL return from block_innermost_frame if there are no
- frames. I don't think I've ever seen this message happen
- otherwise. And returning NULL here is a perfectly legitimate
- thing to do.''
-
- 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;
- }
+ 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
the main function when we created the dummy frame, the dummy frame will
point inside the main function. */
if (this_frame->level >= 0
- && get_frame_type (this_frame) != DUMMY_FRAME
+ && 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
user later decides to enable unwinds past main(), that will
automatically happen. */
{
- frame_debug_got_null_frame (gdb_stdlog, this_frame, "inside main func");
+ frame_debug_got_null_frame (this_frame, "inside main func");
return NULL;
}
frame. */
if (this_frame->level + 2 > backtrace_limit)
{
- frame_debug_got_null_frame (gdb_stdlog, this_frame,
- "backtrace limit exceeded");
+ frame_debug_got_null_frame (this_frame, "backtrace limit exceeded");
return NULL;
}
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
+ 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 (gdb_stdlog, this_frame, "inside entry func");
+ frame_debug_got_null_frame (this_frame, "inside entry func");
return NULL;
}
like a SIGSEGV or a dummy frame, and hence that NORMAL frames
will never unwind a zero PC. */
if (this_frame->level > 0
- && get_frame_type (this_frame) == NORMAL_FRAME
+ && (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 (gdb_stdlog, this_frame, "zero PC");
+ frame_debug_got_null_frame (this_frame, "zero PC");
return NULL;
}
get_frame_pc (struct frame_info *frame)
{
gdb_assert (frame->next != NULL);
- return frame_pc_unwind (frame->next);
+ 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 NEXT_FRAME's caller's code
- block, assuming that the caller is a THIS_TYPE frame. */
+/* Return an address that falls within THIS_FRAME's code block. */
CORE_ADDR
-frame_unwind_address_in_block (struct frame_info *next_frame,
- enum frame_type this_type)
+get_frame_address_in_block (struct frame_info *this_frame)
{
/* A draft address. */
- CORE_ADDR pc = frame_pc_unwind (next_frame);
-
- /* If NEXT_FRAME was called by a signal frame or dummy frame, then
- we shold not adjust the unwound PC. These frames may not call
- their next frame in the normal way; the operating system or GDB
- may have pushed their resume address manually onto the stack, so
- it may be the very first instruction. Even if the resume address
- was not manually pushed, they expect to be returned to. */
- if (this_type != NORMAL_FRAME)
- return pc;
+ CORE_ADDR pc = get_frame_pc (this_frame);
+
+ struct frame_info *next_frame = this_frame->next;
+
+ /* Calling get_frame_pc returns the resume address for THIS_FRAME.
+ Normally the resume address is inside the body of the function
+ associated with THIS_FRAME, but there is a special case: when
+ calling a function which the compiler knows will never return
+ (for instance abort), the call may be the very last instruction
+ in the calling function. The resume address will point after the
+ call and may be at the beginning of a different function
+ entirely.
+
+ If THIS_FRAME is a signal frame or dummy frame, then we should
+ not adjust the unwound PC. For a dummy frame, GDB pushed the
+ resume address manually onto the stack. For a signal frame, the
+ OS may have pushed the resume address manually and invoked the
+ handler (e.g. GNU/Linux), or invoked the trampoline which called
+ the signal handler - but in either case the signal handler is
+ expected to return to the trampoline. So in both of these
+ cases we know that the resume address is executable and
+ related. So we only need to adjust the PC if THIS_FRAME
+ is a normal function.
+
+ If the program has been interrupted while THIS_FRAME is current,
+ then clearly the resume address is inside the associated
+ function. There are three kinds of interruption: debugger stop
+ (next frame will be SENTINEL_FRAME), operating system
+ signal or exception (next frame will be SIGTRAMP_FRAME),
+ or debugger-induced function call (next frame will be
+ DUMMY_FRAME). So we only need to adjust the PC if
+ NEXT_FRAME is a normal function.
+
+ We check the type of NEXT_FRAME first, since it is already
+ known; frame type is determined by the unwinder, and since
+ we have THIS_FRAME we've already selected an unwinder for
+ NEXT_FRAME.
+
+ If the next frame is inlined, we need to keep going until we find
+ the real function - for instance, if a signal handler is invoked
+ while in an inlined function, then the code address of the
+ "calling" normal function should not be adjusted either. */
+
+ while (get_frame_type (next_frame) == INLINE_FRAME)
+ next_frame = next_frame->next;
+
+ if (get_frame_type (next_frame) == NORMAL_FRAME
+ && (get_frame_type (this_frame) == NORMAL_FRAME
+ || get_frame_type (this_frame) == INLINE_FRAME))
+ return pc - 1;
- /* 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_address_in_block (struct frame_info *this_frame)
+int
+get_frame_address_in_block_if_available (struct frame_info *this_frame,
+ CORE_ADDR *pc)
{
- return frame_unwind_address_in_block (this_frame->next,
- get_frame_type (this_frame));
+ 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;
}
-static int
-pc_notcurrent (struct frame_info *frame)
+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
+ be inferred from get_frame_pc. */
+ next_frame = get_next_frame (frame);
+ if (frame_inlined_callees (frame) > 0)
+ {
+ struct symbol *sym;
+
+ if (next_frame)
+ sym = get_frame_function (next_frame);
+ 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->line = SYMBOL_LINE (sym);
+ }
+ else
+ /* If the symbol does not have a location, we don't know where
+ the call site is. Do not pretend to. This is jarring, but
+ we can't do much better. */
+ sal->pc = get_frame_pc (frame);
+
+ return;
+ }
+
/* If FRAME is not the innermost frame, that normally means that
FRAME->pc points at the return instruction (which is *after* the
call instruction), and we want to get the line containing the
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. */
- struct frame_info *next = get_next_frame (frame);
- int notcurrent = (next != NULL && get_frame_type (next) == NORMAL_FRAME);
- return notcurrent;
-}
+ if (!get_frame_pc_if_available (frame, &pc))
+ {
+ init_sal (sal);
+ return;
+ }
-void
-find_frame_sal (struct frame_info *frame, struct symtab_and_line *sal)
-{
- (*sal) = find_pc_line (get_frame_pc (frame), pc_notcurrent (frame));
+ 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
if (get_frame_type (fi) != NORMAL_FRAME)
return 0;
if (fi->base == NULL)
- fi->base = frame_base_find_by_frame (fi->next);
+ fi->base = frame_base_find_by_frame (fi);
/* 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 fi->base->this_base (fi->next, &fi->prologue_cache);
- return fi->base->this_base (fi->next, &fi->base_cache);
+ return fi->base->this_base (fi, &fi->prologue_cache);
+ return fi->base->this_base (fi, &fi->base_cache);
}
CORE_ADDR
get_frame_locals_address (struct frame_info *fi)
{
- void **cache;
if (get_frame_type (fi) != NORMAL_FRAME)
return 0;
/* If there isn't a frame address method, find it. */
if (fi->base == NULL)
- fi->base = frame_base_find_by_frame (fi->next);
+ fi->base = frame_base_find_by_frame (fi);
/* 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)
- cache = &fi->prologue_cache;
- else
- cache = &fi->base_cache;
- return fi->base->this_locals (fi->next, cache);
+ return fi->base->this_locals (fi, &fi->prologue_cache);
+ return fi->base->this_locals (fi, &fi->base_cache);
}
CORE_ADDR
get_frame_args_address (struct frame_info *fi)
{
- void **cache;
if (get_frame_type (fi) != NORMAL_FRAME)
return 0;
/* If there isn't a frame address method, find it. */
if (fi->base == NULL)
- fi->base = frame_base_find_by_frame (fi->next);
+ fi->base = frame_base_find_by_frame (fi);
/* 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)
- cache = &fi->prologue_cache;
- else
- cache = &fi->base_cache;
- return fi->base->this_args (fi->next, cache);
+ return fi->base->this_args (fi, &fi->prologue_cache);
+ return fi->base->this_args (fi, &fi->base_cache);
+}
+
+/* Return true if the frame unwinder for frame FI is UNWINDER; false
+ otherwise. */
+
+int
+frame_unwinder_is (struct frame_info *fi, const struct frame_unwind *unwinder)
+{
+ if (fi->unwind == NULL)
+ frame_unwind_find_by_frame (fi, &fi->prologue_cache);
+ return fi->unwind == unwinder;
}
/* Level of the selected frame: 0 for innermost, 1 for its caller, ...
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);
+ frame_unwind_find_by_frame (frame, &frame->prologue_cache);
return frame->unwind->type;
}
-void
-deprecated_update_frame_pc_hack (struct frame_info *frame, CORE_ADDR pc)
+struct program_space *
+get_frame_program_space (struct frame_info *frame)
{
- if (frame_debug)
- fprintf_unfiltered (gdb_stdlog,
- "{ 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 frames
- are not in the frame chain, it isn't possible to assume that the
- frame has a next. Sigh. */
- if (frame->next != NULL)
- {
- /* While we're at it, update this frame's cached PC value, found
- in the next frame. Oh for the day when "struct frame_info"
- is opaque and this hack on hack can just go away. */
- frame->next->prev_pc.value = pc;
- frame->next->prev_pc.p = 1;
- }
+ return frame->pspace;
}
-void
-deprecated_update_frame_base_hack (struct frame_info *frame, CORE_ADDR base)
+struct program_space *
+frame_unwind_program_space (struct frame_info *this_frame)
{
- if (frame_debug)
- fprintf_unfiltered (gdb_stdlog,
- "{ deprecated_update_frame_base_hack (frame=%d,base=0x%s) }\n",
- frame->level, paddr_nz (base));
- /* See comment in "frame.h". */
- frame->this_id.value.stack_addr = base;
+ 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. */
get_frame_memory_signed (struct frame_info *this_frame, CORE_ADDR addr,
int len)
{
- return read_memory_integer (addr, len);
+ struct gdbarch *gdbarch = get_frame_arch (this_frame);
+ enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
+
+ return read_memory_integer (addr, len, byte_order);
}
ULONGEST
get_frame_memory_unsigned (struct frame_info *this_frame, CORE_ADDR addr,
int len)
{
- return read_memory_unsigned_integer (addr, len);
+ struct gdbarch *gdbarch = get_frame_arch (this_frame);
+ enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
+
+ return read_memory_unsigned_integer (addr, len, byte_order);
}
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);
+ /* NOTE: target_read_memory returns zero on success! */
+ return !target_read_memory (addr, buf, len);
}
-/* Architecture method. */
+/* Architecture methods. */
struct gdbarch *
get_frame_arch (struct frame_info *this_frame)
{
- return current_gdbarch;
+ return frame_unwind_arch (this_frame->next);
}
-/* Stack pointer methods. */
+struct gdbarch *
+frame_unwind_arch (struct frame_info *next_frame)
+{
+ if (!next_frame->prev_arch.p)
+ {
+ struct gdbarch *arch;
-CORE_ADDR
-get_frame_sp (struct frame_info *this_frame)
+ if (next_frame->unwind == NULL)
+ frame_unwind_find_by_frame (next_frame, &next_frame->prologue_cache);
+
+ if (next_frame->unwind->prev_arch != NULL)
+ arch = next_frame->unwind->prev_arch (next_frame,
+ &next_frame->prologue_cache);
+ else
+ arch = get_frame_arch (next_frame);
+
+ next_frame->prev_arch.arch = arch;
+ next_frame->prev_arch.p = 1;
+ if (frame_debug)
+ fprintf_unfiltered (gdb_stdlog,
+ "{ frame_unwind_arch (next_frame=%d) -> %s }\n",
+ next_frame->level,
+ gdbarch_bfd_arch_info (arch)->printable_name);
+ }
+
+ return next_frame->prev_arch.arch;
+}
+
+struct gdbarch *
+frame_unwind_caller_arch (struct frame_info *next_frame)
{
- return frame_sp_unwind (this_frame->next);
+ return frame_unwind_arch (skip_inlined_frames (next_frame));
}
+/* Stack pointer methods. */
+
CORE_ADDR
-frame_sp_unwind (struct frame_info *next_frame)
+get_frame_sp (struct frame_info *this_frame)
{
- struct gdbarch *gdbarch = get_frame_arch (next_frame);
+ struct gdbarch *gdbarch = get_frame_arch (this_frame);
+
/* Normality - an architecture that provides a way of obtaining any
frame inner-most address. */
if (gdbarch_unwind_sp_p (gdbarch))
- return gdbarch_unwind_sp (gdbarch, next_frame);
+ /* NOTE drow/2008-06-28: gdbarch_unwind_sp could be converted to
+ operate on THIS_FRAME now. */
+ return gdbarch_unwind_sp (gdbarch, this_frame->next);
/* Now things are really are grim. Hope that the value returned by
the gdbarch_sp_regnum register is meaningful. */
if (gdbarch_sp_regnum (gdbarch) >= 0)
- return frame_unwind_register_unsigned (next_frame,
- gdbarch_sp_regnum (gdbarch));
+ return get_frame_register_unsigned (this_frame,
+ gdbarch_sp_regnum (gdbarch));
internal_error (__FILE__, __LINE__, _("Missing unwind SP method"));
}
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?)");
}
}
+/* Clean up after a failed (wrong unwinder) attempt to unwind past
+ FRAME. */
+
+static void
+frame_cleanup_after_sniffer (void *arg)
+{
+ struct frame_info *frame = arg;
+
+ /* The sniffer should not allocate a prologue cache if it did not
+ match this frame. */
+ gdb_assert (frame->prologue_cache == NULL);
+
+ /* No sniffer should extend the frame chain; sniff based on what is
+ already certain. */
+ gdb_assert (!frame->prev_p);
+
+ /* The sniffer should not check the frame's ID; that's circular. */
+ gdb_assert (!frame->this_id.p);
+
+ /* Clear cached fields dependent on the unwinder.
+
+ The previous PC is independent of the unwinder, but the previous
+ function is not (see get_frame_address_in_block). */
+ frame->prev_func.p = 0;
+ frame->prev_func.addr = 0;
+
+ /* Discard the unwinder last, so that we can easily find it if an assertion
+ in this function triggers. */
+ frame->unwind = NULL;
+}
+
+/* Set FRAME's unwinder temporarily, so that we can call a sniffer.
+ Return a cleanup which should be called if unwinding fails, and
+ discarded if it succeeds. */
+
+struct cleanup *
+frame_prepare_for_sniffer (struct frame_info *frame,
+ const struct frame_unwind *unwind)
+{
+ gdb_assert (frame->unwind == NULL);
+ frame->unwind = unwind;
+ return make_cleanup (frame_cleanup_after_sniffer, frame);
+}
+
extern initialize_file_ftype _initialize_frame; /* -Wmissing-prototypes */
static struct cmd_list_element *set_backtrace_cmdlist;
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\
+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);
- /* Debug this files internals. */
+ /* Debug this files internals. */
add_setshow_zinteger_cmd ("frame", class_maintenance, &frame_debug, _("\
Set frame debugging."), _("\
Show frame debugging."), _("\
projects / deliverable / binutils-gdb.git / blobdiff