/* Definitions for frame unwinder, for GDB, the GNU debugger.
- Copyright (C) 2003, 2004, 2007, 2008 Free Software Foundation, Inc.
+ Copyright (C) 2003-2020 Free Software Foundation, Inc.
This file is part of GDB.
#include "defs.h"
#include "frame.h"
#include "frame-unwind.h"
-#include "gdb_assert.h"
#include "dummy-frame.h"
+#include "inline-frame.h"
+#include "value.h"
+#include "regcache.h"
#include "gdb_obstack.h"
+#include "target.h"
+#include "gdbarch.h"
static struct gdbarch_data *frame_unwind_data;
struct frame_unwind_table_entry
{
- frame_unwind_sniffer_ftype *sniffer;
const struct frame_unwind *unwinder;
struct frame_unwind_table_entry *next;
};
{
struct frame_unwind_table *table
= OBSTACK_ZALLOC (obstack, struct frame_unwind_table);
+
/* 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->unwinder = &dummy_frame_unwind;
+ table->list->next = OBSTACK_ZALLOC (obstack,
+ struct frame_unwind_table_entry);
+ table->list->next->unwinder = &inline_frame_unwind;
/* The insertion point for OSABI sniffers. */
- table->osabi_head = &table->list->next;
+ table->osabi_head = &table->list->next->next;
return table;
}
-void
-frame_unwind_append_sniffer (struct gdbarch *gdbarch,
- frame_unwind_sniffer_ftype *sniffer)
-{
- struct frame_unwind_table *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. */
- for (ip = table->osabi_head; (*ip) != NULL; ip = &(*ip)->next);
- (*ip) = GDBARCH_OBSTACK_ZALLOC (gdbarch, struct frame_unwind_table_entry);
- (*ip)->sniffer = sniffer;
-}
-
void
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. */
(*table->osabi_head) = entry;
}
-const struct frame_unwind *
-frame_unwind_find_by_frame (struct frame_info *next_frame, void **this_cache)
+void
+frame_unwind_append_unwinder (struct gdbarch *gdbarch,
+ const struct frame_unwind *unwinder)
{
- int i;
- struct gdbarch *gdbarch = get_frame_arch (next_frame);
- struct frame_unwind_table *table = gdbarch_data (gdbarch, frame_unwind_data);
- struct frame_unwind_table_entry *entry;
- for (entry = table->list; entry != NULL; entry = entry->next)
+ 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. */
+ for (ip = table->osabi_head; (*ip) != NULL; ip = &(*ip)->next);
+ (*ip) = GDBARCH_OBSTACK_ZALLOC (gdbarch, struct frame_unwind_table_entry);
+ (*ip)->unwinder = unwinder;
+}
+
+/* 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. */
+
+static int
+frame_unwind_try_unwinder (struct frame_info *this_frame, void **this_cache,
+ const struct frame_unwind *unwinder)
+{
+ int res = 0;
+
+ frame_prepare_for_sniffer (this_frame, unwinder);
+
+ try
{
- if (entry->sniffer != NULL)
- {
- const struct frame_unwind *desc = NULL;
- desc = entry->sniffer (next_frame);
- if (desc != NULL)
- return desc;
- }
- if (entry->unwinder != NULL)
+ 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);
+
+ if (ex.error == NOT_AVAILABLE_ERROR)
{
- if (entry->unwinder->sniffer (entry->unwinder, next_frame,
- this_cache))
- return entry->unwinder;
+ /* 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;
}
+ 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"));
}
-extern initialize_file_ftype _initialize_frame_unwind; /* -Wmissing-prototypes */
+/* A default frame sniffer which always accepts the frame. Used by
+ fallback prologue unwinders. */
+
+int
+default_frame_sniffer (const struct frame_unwind *self,
+ struct frame_info *this_frame,
+ void **this_prologue_cache)
+{
+ return 1;
+}
+
+/* The default frame unwinder stop_reason callback. */
+
+enum unwind_stop_reason
+default_frame_unwind_stop_reason (struct frame_info *this_frame,
+ void **this_cache)
+{
+ 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
+ a (possibly lazy) value of the appropriate type. */
+
+/* Return a value which indicates that FRAME did not save REGNUM. */
+
+struct value *
+frame_unwind_got_optimized (struct frame_info *frame, int regnum)
+{
+ 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 a value which indicates that FRAME copied REGNUM into
+ register NEW_REGNUM. */
+
+struct value *
+frame_unwind_got_register (struct frame_info *frame,
+ int regnum, int new_regnum)
+{
+ return value_of_register_lazy (frame, new_regnum);
+}
+
+/* Return a value which indicates that FRAME saved REGNUM in memory at
+ ADDR. */
+
+struct value *
+frame_unwind_got_memory (struct frame_info *frame, int regnum, CORE_ADDR addr)
+{
+ struct gdbarch *gdbarch = frame_unwind_arch (frame);
+ struct value *v = value_at_lazy (register_type (gdbarch, regnum), addr);
+
+ set_value_stack (v, 1);
+ return v;
+}
+
+/* Return a value which indicates that FRAME's saved version of
+ REGNUM has a known constant (computed) value of VAL. */
+
+struct value *
+frame_unwind_got_constant (struct frame_info *frame, int regnum,
+ ULONGEST val)
+{
+ struct gdbarch *gdbarch = frame_unwind_arch (frame);
+ enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
+ struct value *reg_val;
+
+ reg_val = value_zero (register_type (gdbarch, regnum), not_lval);
+ store_unsigned_integer (value_contents_writeable (reg_val),
+ 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)
+{
+ 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));
+ return reg_val;
+}
+
+/* Return a value which indicates that FRAME's saved version of REGNUM
+ has a known constant (computed) value of ADDR. Convert the
+ CORE_ADDR to a target address if necessary. */
+
+struct value *
+frame_unwind_got_address (struct frame_info *frame, int regnum,
+ CORE_ADDR addr)
+{
+ struct gdbarch *gdbarch = frame_unwind_arch (frame);
+ struct value *reg_val;
+
+ reg_val = value_zero (register_type (gdbarch, regnum), not_lval);
+ pack_long (value_contents_writeable (reg_val),
+ register_type (gdbarch, regnum), addr);
+ return reg_val;
+}
void
_initialize_frame_unwind (void)