+/* Helper for value_fetch_lazy when the value is a bitfield. */
+
+static void
+value_fetch_lazy_bitfield (struct value *val)
+{
+ gdb_assert (value_bitsize (val) != 0);
+
+ /* To read a lazy bitfield, read the entire enclosing value. This
+ prevents reading the same block of (possibly volatile) memory once
+ per bitfield. It would be even better to read only the containing
+ word, but we have no way to record that just specific bits of a
+ value have been fetched. */
+ struct value *parent = value_parent (val);
+
+ if (value_lazy (parent))
+ value_fetch_lazy (parent);
+
+ unpack_value_bitfield (val, value_bitpos (val), value_bitsize (val),
+ value_contents_for_printing (parent),
+ value_offset (val), parent);
+}
+
+/* Helper for value_fetch_lazy when the value is in memory. */
+
+static void
+value_fetch_lazy_memory (struct value *val)
+{
+ gdb_assert (VALUE_LVAL (val) == lval_memory);
+
+ CORE_ADDR addr = value_address (val);
+ struct type *type = check_typedef (value_enclosing_type (val));
+
+ if (TYPE_LENGTH (type))
+ read_value_memory (val, 0, value_stack (val),
+ addr, value_contents_all_raw (val),
+ type_length_units (type));
+}
+
+/* Helper for value_fetch_lazy when the value is in a register. */
+
+static void
+value_fetch_lazy_register (struct value *val)
+{
+ struct frame_info *next_frame;
+ int regnum;
+ struct type *type = check_typedef (value_type (val));
+ struct value *new_val = val, *mark = value_mark ();
+
+ /* Offsets are not supported here; lazy register values must
+ refer to the entire register. */
+ gdb_assert (value_offset (val) == 0);
+
+ while (VALUE_LVAL (new_val) == lval_register && value_lazy (new_val))
+ {
+ struct frame_id next_frame_id = VALUE_NEXT_FRAME_ID (new_val);
+
+ next_frame = frame_find_by_id (next_frame_id);
+ regnum = VALUE_REGNUM (new_val);
+
+ gdb_assert (next_frame != NULL);
+
+ /* Convertible register routines are used for multi-register
+ values and for interpretation in different types
+ (e.g. float or int from a double register). Lazy
+ register values should have the register's natural type,
+ so they do not apply. */
+ gdb_assert (!gdbarch_convert_register_p (get_frame_arch (next_frame),
+ regnum, type));
+
+ /* FRAME was obtained, above, via VALUE_NEXT_FRAME_ID.
+ Since a "->next" operation was performed when setting
+ this field, we do not need to perform a "next" operation
+ again when unwinding the register. That's why
+ frame_unwind_register_value() is called here instead of
+ get_frame_register_value(). */
+ new_val = frame_unwind_register_value (next_frame, regnum);
+
+ /* If we get another lazy lval_register value, it means the
+ register is found by reading it from NEXT_FRAME's next frame.
+ frame_unwind_register_value should never return a value with
+ the frame id pointing to NEXT_FRAME. If it does, it means we
+ either have two consecutive frames with the same frame id
+ in the frame chain, or some code is trying to unwind
+ behind get_prev_frame's back (e.g., a frame unwind
+ sniffer trying to unwind), bypassing its validations. In
+ any case, it should always be an internal error to end up
+ in this situation. */
+ if (VALUE_LVAL (new_val) == lval_register
+ && value_lazy (new_val)
+ && frame_id_eq (VALUE_NEXT_FRAME_ID (new_val), next_frame_id))
+ internal_error (__FILE__, __LINE__,
+ _("infinite loop while fetching a register"));
+ }
+
+ /* If it's still lazy (for instance, a saved register on the
+ stack), fetch it. */
+ if (value_lazy (new_val))
+ value_fetch_lazy (new_val);
+
+ /* Copy the contents and the unavailability/optimized-out
+ meta-data from NEW_VAL to VAL. */
+ set_value_lazy (val, 0);
+ value_contents_copy (val, value_embedded_offset (val),
+ new_val, value_embedded_offset (new_val),
+ type_length_units (type));
+
+ if (frame_debug)
+ {
+ struct gdbarch *gdbarch;
+ struct frame_info *frame;
+ /* VALUE_FRAME_ID is used here, instead of VALUE_NEXT_FRAME_ID,
+ so that the frame level will be shown correctly. */
+ frame = frame_find_by_id (VALUE_FRAME_ID (val));
+ regnum = VALUE_REGNUM (val);
+ gdbarch = get_frame_arch (frame);
+
+ fprintf_unfiltered (gdb_stdlog,
+ "{ value_fetch_lazy "
+ "(frame=%d,regnum=%d(%s),...) ",
+ frame_relative_level (frame), regnum,
+ user_reg_map_regnum_to_name (gdbarch, regnum));
+
+ fprintf_unfiltered (gdb_stdlog, "->");
+ if (value_optimized_out (new_val))
+ {
+ fprintf_unfiltered (gdb_stdlog, " ");
+ val_print_optimized_out (new_val, gdb_stdlog);
+ }
+ else
+ {
+ int i;
+ const gdb_byte *buf = value_contents (new_val);
+
+ if (VALUE_LVAL (new_val) == lval_register)
+ fprintf_unfiltered (gdb_stdlog, " register=%d",
+ VALUE_REGNUM (new_val));
+ else if (VALUE_LVAL (new_val) == lval_memory)
+ fprintf_unfiltered (gdb_stdlog, " address=%s",
+ paddress (gdbarch,
+ value_address (new_val)));
+ else
+ fprintf_unfiltered (gdb_stdlog, " computed");
+
+ 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");
+ }
+
+ /* Dispose of the intermediate values. This prevents
+ watchpoints from trying to watch the saved frame pointer. */
+ value_free_to_mark (mark);
+}
+
projects / deliverable / binutils-gdb.git / blobdiff