py/objgenerator: Eliminate need for mp_obj_gen_wrap wrapper instances.

For generating functions there is no need to wrap the bytecode function in
a generator wrapper instance.  Instead the type of the bytecode function
can be changed to mp_type_gen_wrap.  This reduces code size and saves a
block of GC heap RAM for each generator.

1 files changed, 4 insertions, 5 deletions

diff --git a/py/emitglue.c b/py/emitglue.c
index 74bf8ddca2..a7fff0e0eb 100644
--- a/py/emitglue.c
+++ b/py/emitglue.c
@@ -146,14 +146,13 @@ mp_obj_t mp_make_function_from_raw_code(const mp_raw_code_t *rc, mp_obj_t def_ar
             // rc->kind should always be set and BYTECODE is the only remaining case
             assert(rc->kind == MP_CODE_BYTECODE);
             fun = mp_obj_new_fun_bc(def_args, def_kw_args, rc->data.u_byte.bytecode, rc->data.u_byte.const_table);
+            // check for generator functions and if so change the type of the object
+            if ((rc->scope_flags & MP_SCOPE_FLAG_GENERATOR) != 0) {
+                ((mp_obj_base_t*)MP_OBJ_TO_PTR(fun))->type = &mp_type_gen_wrap;
+            }
             break;
     }
 
-    // check for generator functions and if so wrap in generator object
-    if ((rc->scope_flags & MP_SCOPE_FLAG_GENERATOR) != 0) {
-        fun = mp_obj_new_gen_wrap(fun);
-    }
-
     return fun;
 }