+ /* Structures bigger than a pair of words can't be returned in
+ registers. */
+ if (TYPE_LENGTH (type) > 8)
+ return 1;
+
+ switch (TYPE_CODE (type))
+ {
+ case TYPE_CODE_STRUCT:
+ case TYPE_CODE_UNION:
+ /* Structures with a single field are handled as the field
+ itself. */
+ if (TYPE_NFIELDS (type) == 1)
+ return mn10300_use_struct_convention (TYPE_FIELD_TYPE (type, 0));
+
+ /* Structures with word or double-word size are passed in memory, as
+ long as they require at least word alignment. */
+ if (mn10300_type_align (type) >= 4)
+ return 0;
+
+ return 1;
+
+ /* Arrays are addressable, so they're never returned in
+ registers. This condition can only hold when the array is
+ the only field of a struct or union. */
+ case TYPE_CODE_ARRAY:
+ return 1;
+
+ case TYPE_CODE_TYPEDEF:
+ return mn10300_use_struct_convention (check_typedef (type));
+
+ default:
+ return 0;
+ }
+}
+
+/* Determine, for architecture GDBARCH, how a return value of TYPE
+ should be returned. If it is supposed to be returned in registers,
+ and READBUF is non-zero, read the appropriate value from REGCACHE,
+ and copy it into READBUF. If WRITEBUF is non-zero, write the value
+ from WRITEBUF into REGCACHE. */
+
+static enum return_value_convention
+mn10300_return_value (struct gdbarch *gdbarch, struct type *type,
+ struct regcache *regcache, void *readbuf,
+ const void *writebuf)
+{
+ if (mn10300_use_struct_convention (type))
+ return RETURN_VALUE_STRUCT_CONVENTION;
+
+ if (readbuf)
+ mn10300_extract_return_value (gdbarch, type, regcache, readbuf);
+ if (writebuf)
+ mn10300_store_return_value (gdbarch, type, regcache, writebuf);
+
+ return RETURN_VALUE_REGISTER_CONVENTION;