/* Cache and manage frames for GDB, the GNU debugger.
- Copyright (C) 1986-2013 Free Software Foundation, Inc.
+ Copyright (C) 1986-2014 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 <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 "hashtab.h"
#include "valprint.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);
+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
/* 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. Create a hash table
const struct frame_id f_id = frame->this_id.value;
hashval_t hash = 0;
- gdb_assert (f_id.stack_addr_p || f_id.code_addr_p
+ gdb_assert (f_id.stack_status != FID_STACK_INVALID
+ || f_id.code_addr_p
|| f_id.special_addr_p);
- if (f_id.stack_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)
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
+ 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.artificial_depth)
fprintf_unfiltered (file, ",artificial=%d", id.artificial_depth);
+
fprintf_unfiltered (file, "}");
}
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)
static struct frame_info *
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). This is safe, because as these frames
+ are made up by GDB, there must be a real frame in the chain
+ below. */
while (get_frame_type (frame) == INLINE_FRAME
|| get_frame_type (frame) == TAILCALL_FRAME)
- frame = get_prev_frame (frame);
+ frame = get_prev_frame_always (frame);
return frame;
}
{
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_artificial_frames (next_frame);
- this_frame = get_prev_frame_1 (next_frame);
+ this_frame = get_prev_frame_always (next_frame);
if (this_frame)
return get_frame_id (skip_artificial_frames (this_frame));
else
}
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 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 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
+ || l.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)
{
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.artificial_depth > r.artificial_depth
&& l.stack_addr == r.stack_addr
&& 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);
return NULL;
}
-static int
-frame_unwind_pc_if_available (struct frame_info *this_frame, CORE_ADDR *pc)
+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)
{
if (gdbarch_unwind_pc_p (frame_unwind_arch (this_frame)))
{
{
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)
+ if (ex.reason < 0)
{
- throw_exception (ex);
+ 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);
}
else
{
this_frame->prev_pc.value = pc;
- this_frame->prev_pc.p = 1;
+ this_frame->prev_pc.status = CC_VALUE;
if (frame_debug)
fprintf_unfiltered (gdb_stdlog,
"{ frame_unwind_pc (this_frame=%d) "
else
internal_error (__FILE__, __LINE__, _("No unwind_pc method"));
}
- 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))
+ 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
- return pc;
+ internal_error (__FILE__, __LINE__,
+ "unexpected prev_pc status: %d",
+ (int) this_frame->prev_pc.status);
}
CORE_ADDR
}
int
-frame_unwind_caller_pc_if_available (struct frame_info *this_frame,
- CORE_ADDR *pc)
-{
- return frame_unwind_pc_if_available (skip_artificial_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;
{
/* 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."));
&lval, &addr, &realnum, buf);
if (optimized)
- error (_("Register %d was not saved"), regnum);
+ throw_error (OPTIMIZED_OUT_ERROR,
+ _("Register %d was not saved"), regnum);
if (unavailable)
throw_error (NOT_AVAILABLE_ERROR,
_("Register %d is not available"), regnum);
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;
}
}
+/* Called during frame unwinding to remove a previous frame pointer from a
+ frame passed in ARG. */
+
+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
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);
if (prev_frame == NULL)
return NULL;
- compute_frame_id (prev_frame);
- if (frame_stash_add (prev_frame))
- 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);
- /* Another frame with the same id was already in the stash. We just
- detected a cycle. */
- if (frame_debug)
+ compute_frame_id (prev_frame);
+ if (!frame_stash_add (prev_frame))
{
- fprintf_unfiltered (gdb_stdlog, "-> ");
- fprint_frame (gdb_stdlog, NULL);
- fprintf_unfiltered (gdb_stdlog, " // this frame has same ID }\n");
+ /* 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;
}
- this_frame->stop_reason = UNWIND_SAME_ID;
- /* Unlink. */
- prev_frame->next = NULL;
- this_frame->prev = NULL;
- return NULL;
-}
-/* Return a "struct frame_info" corresponding to the frame that called
- THIS_FRAME. Returns NULL if there is no such frame.
+ discard_cleanups (prev_frame_cleanup);
+ return prev_frame;
+}
- Unlike get_prev_frame, this function always tries to unwind the
- 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
&this_frame->prologue_cache);
if (this_frame->stop_reason != UNWIND_NO_REASON)
- return NULL;
+ {
+ 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, " // %s }\n",
+ frame_stop_reason_symbol_string (reason));
+ }
+ return NULL;
+ }
/* Check that this frame's ID isn't inner to (younger, below, next)
the next frame. This happens when a frame unwind goes backwards.
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;
this_pc_in_block = get_frame_address_in_block (this_frame);
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)
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)
+{
+ volatile struct gdb_exception ex;
+ struct frame_info *prev_frame = NULL;
+
+ TRY_CATCH (ex, RETURN_MASK_ERROR)
+ {
+ prev_frame = get_prev_frame_always_1 (this_frame);
+ }
+ if (ex.reason < 0)
+ {
+ 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 = frame_obstack_zalloc (size);
+ memcpy (stop_string, ex.message, size);
+ this_frame->stop_string = stop_string;
+ }
+ prev_frame = NULL;
+ }
+ else
+ throw_exception (ex);
+ }
+
+ return prev_frame;
+}
+
/* Construct a new "struct frame_info" and link it previous to
this_frame. */
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);
}
return NULL;
}
- return get_prev_frame_1 (this_frame);
+ return get_prev_frame_always (this_frame);
}
CORE_ADDR
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)
{
}
}
+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;
+
+ /* Return the generic string if we have nothing better. */
+ return unwind_stop_reason_to_string (fi->stop_reason);
+}
+
+/* Return the enum symbol name of REASON as a string, to use in debug
+ output. */
+
+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
+
+ default:
+ internal_error (__FILE__, __LINE__,
+ "Invalid frame stop reason");
+ }
+}
+
/* Clean up after a failed (wrong unwinder) attempt to unwind past
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
projects / platform / upstream / binutils.git / blobdiff