/* Definitions for frame unwinder, for GDB, the GNU debugger.
- Copyright (C) 2003-2013 Free Software Foundation, Inc.
+ Copyright (C) 2003-2020 Free Software Foundation, Inc.
This file is part of GDB.
#include "inline-frame.h"
#include "value.h"
#include "regcache.h"
-#include "exceptions.h"
-#include "gdb_assert.h"
#include "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;
}
frame_unwind_prepend_unwinder (struct gdbarch *gdbarch,
const struct frame_unwind *unwinder)
{
- struct frame_unwind_table *table = gdbarch_data (gdbarch, frame_unwind_data);
+ struct frame_unwind_table *table
+ = (struct frame_unwind_table *) gdbarch_data (gdbarch, frame_unwind_data);
struct frame_unwind_table_entry *entry;
/* Insert the new entry at the start of the list. */
frame_unwind_append_unwinder (struct gdbarch *gdbarch,
const struct frame_unwind *unwinder)
{
- struct frame_unwind_table *table = gdbarch_data (gdbarch, frame_unwind_data);
+ struct frame_unwind_table *table
+ = (struct frame_unwind_table *) gdbarch_data (gdbarch, frame_unwind_data);
struct frame_unwind_table_entry **ip;
/* Find the end of the list and insert the new entry there. */
(*ip)->unwinder = unwinder;
}
-/* Iterate through sniffers for THIS_FRAME frame until one returns with an
- unwinder implementation. THIS_FRAME->UNWIND must be NULL, it will get set
- by this function. Possibly initialize THIS_CACHE. */
+/* Call SNIFFER from UNWINDER. If it succeeded set UNWINDER for
+ THIS_FRAME and return 1. Otherwise the function keeps THIS_FRAME
+ unchanged and returns 0. */
-void
-frame_unwind_find_by_frame (struct frame_info *this_frame, void **this_cache)
+static int
+frame_unwind_try_unwinder (struct frame_info *this_frame, void **this_cache,
+ const struct frame_unwind *unwinder)
{
- struct gdbarch *gdbarch = get_frame_arch (this_frame);
- struct frame_unwind_table *table = gdbarch_data (gdbarch, frame_unwind_data);
- struct frame_unwind_table_entry *entry;
+ int res = 0;
- for (entry = table->list; entry != NULL; entry = entry->next)
- {
- struct cleanup *old_cleanup;
- volatile struct gdb_exception ex;
- int res = 0;
+ frame_prepare_for_sniffer (this_frame, unwinder);
- old_cleanup = frame_prepare_for_sniffer (this_frame, entry->unwinder);
+ try
+ {
+ res = unwinder->sniffer (unwinder, this_frame, this_cache);
+ }
+ catch (const gdb_exception &ex)
+ {
+ /* Catch all exceptions, caused by either interrupt or error.
+ Reset *THIS_CACHE. */
+ *this_cache = NULL;
+ frame_cleanup_after_sniffer (this_frame);
- TRY_CATCH (ex, RETURN_MASK_ERROR)
- {
- res = entry->unwinder->sniffer (entry->unwinder, this_frame,
- this_cache);
- }
- if (ex.reason < 0 && ex.error == NOT_AVAILABLE_ERROR)
+ if (ex.error == NOT_AVAILABLE_ERROR)
{
/* This usually means that not even the PC is available,
thus most unwinders aren't able to determine if they're
the best fit. Keep trying. Fallback prologue unwinders
should always accept the frame. */
+ return 0;
}
- else if (ex.reason < 0)
- throw_exception (ex);
- else if (res)
- {
- discard_cleanups (old_cleanup);
- return;
- }
-
- do_cleanups (old_cleanup);
+ throw;
}
+
+ if (res)
+ return 1;
+ else
+ {
+ /* Don't set *THIS_CACHE to NULL here, because sniffer has to do
+ so. */
+ frame_cleanup_after_sniffer (this_frame);
+ return 0;
+ }
+ gdb_assert_not_reached ("frame_unwind_try_unwinder");
+}
+
+/* Iterate through sniffers for THIS_FRAME frame until one returns with an
+ unwinder implementation. THIS_FRAME->UNWIND must be NULL, it will get set
+ by this function. Possibly initialize THIS_CACHE. */
+
+void
+frame_unwind_find_by_frame (struct frame_info *this_frame, void **this_cache)
+{
+ struct gdbarch *gdbarch = get_frame_arch (this_frame);
+ struct frame_unwind_table *table
+ = (struct frame_unwind_table *) gdbarch_data (gdbarch, frame_unwind_data);
+ struct frame_unwind_table_entry *entry;
+ const struct frame_unwind *unwinder_from_target;
+
+ unwinder_from_target = target_get_unwinder ();
+ if (unwinder_from_target != NULL
+ && frame_unwind_try_unwinder (this_frame, this_cache,
+ 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))
+ return;
+
+ for (entry = table->list; entry != NULL; entry = entry->next)
+ if (frame_unwind_try_unwinder (this_frame, this_cache, entry->unwinder))
+ return;
+
internal_error (__FILE__, __LINE__, _("frame_unwind_find_by_frame failed"));
}
return 1;
}
-/* A default frame unwinder stop_reason callback that always claims
- the frame is unwindable. */
+/* The default frame unwinder stop_reason callback. */
enum unwind_stop_reason
default_frame_unwind_stop_reason (struct frame_info *this_frame,
void **this_cache)
{
- return UNWIND_NO_REASON;
+ struct frame_id this_id = get_frame_id (this_frame);
+
+ if (frame_id_eq (this_id, outer_frame_id))
+ return UNWIND_OUTERMOST;
+ else
+ 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
frame_unwind_got_optimized (struct frame_info *frame, int regnum)
{
struct gdbarch *gdbarch = frame_unwind_arch (frame);
- struct value *reg_val;
-
- reg_val = value_zero (register_type (gdbarch, regnum), not_lval);
- set_value_optimized_out (reg_val, 1);
- return reg_val;
+ 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 a value which indicates that FRAME copied REGNUM into
return reg_val;
}
-/* -Wmissing-prototypes */
-extern initialize_file_ftype _initialize_frame_unwind;
-
+void _initialize_frame_unwind ();
void
-_initialize_frame_unwind (void)
+_initialize_frame_unwind ()
{
frame_unwind_data = gdbarch_data_register_pre_init (frame_unwind_init);
}
projects / deliverable / binutils-gdb.git / blobdiff