Remove mp_obj_type_t.methods entry and use .locals_dict instead.

Originally, .methods was used for methods in a ROM class, and
locals_dict for methods in a user-created class.  That distinction is
unnecessary, and we can use locals_dict for ROM classes now that we have
ROMable maps.

This removes an entry in the bloated mp_obj_type_t struct, saving a word
for each ROM object and each RAM object.  ROM objects that have a
methods table (now a locals_dict) need an extra word in total (removed
the methods pointer (1 word), no longer need the sentinel (2 words), but
now need an mp_obj_dict_t wrapper (4 words)).  But RAM objects save a
word because they never used the methods entry.

Overall the ROM usage is down by a few hundred bytes, and RAM usage is
down 1 word per user-defined type/class.

There is less code (no need to check 2 tables), and now consistent with
the way ROM modules have their tables initialised.

Efficiency is very close to equivaluent.

1 files changed, 7 insertions, 5 deletions

diff --git a/unix/main.c b/unix/main.c
index e8452fd8cc..6b25988759 100644
--- a/unix/main.c
+++ b/unix/main.c
@@ -15,6 +15,7 @@
 #include "lexerunix.h"
 #include "parse.h"
 #include "obj.h"
+#include "map.h"
 #include "parsehelper.h"
 #include "compile.h"
 #include "runtime0.h"
@@ -191,17 +192,18 @@ static mp_obj_t test_set(mp_obj_t self_in, mp_obj_t arg) {
 static MP_DEFINE_CONST_FUN_OBJ_1(test_get_obj, test_get);
 static MP_DEFINE_CONST_FUN_OBJ_2(test_set_obj, test_set);
 
-static const mp_method_t test_methods[] = {
-    { MP_QSTR_get, &test_get_obj },
-    { MP_QSTR_set, &test_set_obj },
-    { MP_QSTR_NULL, NULL },
+static const mp_map_elem_t test_locals_dict_table[] = {
+    { MP_OBJ_NEW_QSTR(MP_QSTR_get), (mp_obj_t)&test_get_obj },
+    { MP_OBJ_NEW_QSTR(MP_QSTR_set), (mp_obj_t)&test_set_obj },
 };
 
+STATIC MP_DEFINE_CONST_DICT(test_locals_dict, test_locals_dict_table);
+
 static const mp_obj_type_t test_type = {
     { &mp_type_type },
     .name = MP_QSTR_Test,
     .print = test_print,
-    .methods = test_methods,
+    .locals_dict = (mp_obj_t)&test_locals_dict,
 };
 
 mp_obj_t test_obj_new(int value) {