/* Definitions for frame unwinder, for GDB, the GNU debugger.
- Copyright (C) 2003-2018 Free Software Foundation, Inc.
+ Copyright (C) 2003-2022 Free Software Foundation, Inc.
This file is part of GDB.
#include "inline-frame.h"
#include "value.h"
#include "regcache.h"
-#include "gdb_obstack.h"
+#include "gdbsupport/gdb_obstack.h"
#include "target.h"
+#include "gdbarch.h"
+#include "dwarf2/frame-tailcall.h"
static struct gdbarch_data *frame_unwind_data;
struct frame_unwind_table_entry **osabi_head;
};
+/* A helper function to add an unwinder to a list. LINK says where to
+ install the new unwinder. The new link is returned. */
+
+static struct frame_unwind_table_entry **
+add_unwinder (struct obstack *obstack, const struct frame_unwind *unwinder,
+ struct frame_unwind_table_entry **link)
+{
+ *link = OBSTACK_ZALLOC (obstack, struct frame_unwind_table_entry);
+ (*link)->unwinder = unwinder;
+ return &(*link)->next;
+}
+
static void *
frame_unwind_init (struct obstack *obstack)
{
/* Start the table out with a few default sniffers. OSABI code
can't override this. */
- table->list = OBSTACK_ZALLOC (obstack, struct frame_unwind_table_entry);
- table->list->unwinder = &dummy_frame_unwind;
- table->list->next = OBSTACK_ZALLOC (obstack,
- struct frame_unwind_table_entry);
- table->list->next->unwinder = &inline_frame_unwind;
+ struct frame_unwind_table_entry **link = &table->list;
+
+ link = add_unwinder (obstack, &dummy_frame_unwind, link);
+ /* The DWARF tailcall sniffer must come before the inline sniffer.
+ Otherwise, we can end up in a situation where a DWARF frame finds
+ tailcall information, but then the inline sniffer claims a frame
+ before the tailcall sniffer, resulting in confusion. This is
+ safe to do always because the tailcall sniffer can only ever be
+ activated if the newer frame was created using the DWARF
+ unwinder, and it also found tailcall information. */
+ link = add_unwinder (obstack, &dwarf2_tailcall_frame_unwind, link);
+ link = add_unwinder (obstack, &inline_frame_unwind, link);
+
/* The insertion point for OSABI sniffers. */
- table->osabi_head = &table->list->next->next;
+ table->osabi_head = link;
return table;
}
static int
frame_unwind_try_unwinder (struct frame_info *this_frame, void **this_cache,
- const struct frame_unwind *unwinder)
+ const struct frame_unwind *unwinder)
{
int res = 0;
+ unsigned int entry_generation = get_frame_cache_generation ();
+
frame_prepare_for_sniffer (this_frame, unwinder);
- TRY
+ try
{
+ frame_debug_printf ("trying unwinder \"%s\"", unwinder->name);
res = unwinder->sniffer (unwinder, this_frame, this_cache);
}
- CATCH (ex, RETURN_MASK_ALL)
+ catch (const gdb_exception &ex)
{
+ frame_debug_printf ("caught exception: %s", ex.message->c_str ());
+
/* Catch all exceptions, caused by either interrupt or error.
- Reset *THIS_CACHE. */
- *this_cache = NULL;
- frame_cleanup_after_sniffer (this_frame);
+ Reset *THIS_CACHE, unless something reinitialized the frame
+ cache meanwhile, in which case THIS_FRAME/THIS_CACHE are now
+ dangling. */
+ if (get_frame_cache_generation () == entry_generation)
+ {
+ *this_cache = NULL;
+ frame_cleanup_after_sniffer (this_frame);
+ }
if (ex.error == NOT_AVAILABLE_ERROR)
{
should always accept the frame. */
return 0;
}
- throw_exception (ex);
+ throw;
}
- END_CATCH
if (res)
- return 1;
+ {
+ frame_debug_printf ("yes");
+ return 1;
+ }
else
{
+ frame_debug_printf ("no");
/* Don't set *THIS_CACHE to NULL here, because sniffer has to do
so. */
frame_cleanup_after_sniffer (this_frame);
void
frame_unwind_find_by_frame (struct frame_info *this_frame, void **this_cache)
{
+ FRAME_SCOPED_DEBUG_ENTER_EXIT;
+ frame_debug_printf ("this_frame=%d", frame_relative_level (this_frame));
+
struct gdbarch *gdbarch = get_frame_arch (this_frame);
struct frame_unwind_table *table
= (struct frame_unwind_table *) gdbarch_data (gdbarch, frame_unwind_data);
unwinder_from_target = target_get_unwinder ();
if (unwinder_from_target != NULL
&& frame_unwind_try_unwinder (this_frame, this_cache,
- unwinder_from_target))
+ unwinder_from_target))
return;
unwinder_from_target = target_get_tailcall_unwinder ();
if (unwinder_from_target != NULL
&& frame_unwind_try_unwinder (this_frame, this_cache,
- unwinder_from_target))
+ unwinder_from_target))
return;
for (entry = table->list; entry != NULL; entry = entry->next)
return UNWIND_NO_REASON;
}
+/* See frame-unwind.h. */
+
+CORE_ADDR
+default_unwind_pc (struct gdbarch *gdbarch, struct frame_info *next_frame)
+{
+ int pc_regnum = gdbarch_pc_regnum (gdbarch);
+ CORE_ADDR pc = frame_unwind_register_unsigned (next_frame, pc_regnum);
+ pc = gdbarch_addr_bits_remove (gdbarch, pc);
+ return pc;
+}
+
+/* See frame-unwind.h. */
+
+CORE_ADDR
+default_unwind_sp (struct gdbarch *gdbarch, struct frame_info *next_frame)
+{
+ int sp_regnum = gdbarch_sp_regnum (gdbarch);
+ return frame_unwind_register_unsigned (next_frame, sp_regnum);
+}
+
/* Helper functions for value-based register unwinding. These return
a (possibly lazy) value of the appropriate type. */
{
struct gdbarch *gdbarch = frame_unwind_arch (frame);
struct type *type = register_type (gdbarch, regnum);
- struct value *val;
-
- /* Return an lval_register value, so that we print it as
- "<not saved>". */
- val = allocate_value_lazy (type);
- set_value_lazy (val, 0);
- mark_value_bytes_optimized_out (val, 0, TYPE_LENGTH (type));
- VALUE_LVAL (val) = lval_register;
- VALUE_REGNUM (val) = regnum;
- VALUE_NEXT_FRAME_ID (val)
- = get_frame_id (get_next_frame_sentinel_okay (frame));
- return val;
+
+ return allocate_optimized_out_value (type);
}
/* Return a value which indicates that FRAME copied REGNUM into
struct value *reg_val;
reg_val = value_zero (register_type (gdbarch, regnum), not_lval);
- store_unsigned_integer (value_contents_writeable (reg_val),
+ store_unsigned_integer (value_contents_writeable (reg_val).data (),
register_size (gdbarch, regnum), byte_order, val);
return reg_val;
}
struct value *
-frame_unwind_got_bytes (struct frame_info *frame, int regnum, gdb_byte *buf)
+frame_unwind_got_bytes (struct frame_info *frame, int regnum, const gdb_byte *buf)
{
struct gdbarch *gdbarch = frame_unwind_arch (frame);
struct value *reg_val;
reg_val = value_zero (register_type (gdbarch, regnum), not_lval);
- memcpy (value_contents_raw (reg_val), buf, register_size (gdbarch, regnum));
+ memcpy (value_contents_raw (reg_val).data (), buf,
+ register_size (gdbarch, regnum));
return reg_val;
}
struct value *reg_val;
reg_val = value_zero (register_type (gdbarch, regnum), not_lval);
- pack_long (value_contents_writeable (reg_val),
+ pack_long (value_contents_writeable (reg_val).data (),
register_type (gdbarch, regnum), addr);
return reg_val;
}
+void _initialize_frame_unwind ();
void
-_initialize_frame_unwind (void)
+_initialize_frame_unwind ()
{
frame_unwind_data = gdbarch_data_register_pre_init (frame_unwind_init);
}