py: Merge BINARY_OP_SUBSCR and store_subscr (w/ delete) into subscr.

mp_obj_t->subscr now does load/store/delete.

py/bc0.h

@@ -23,6 +23,7 @@
 #define MP_BC_LOAD_ATTR          (0x28) // qstr
 #define MP_BC_LOAD_METHOD        (0x29) // qstr
 #define MP_BC_LOAD_BUILD_CLASS   (0x2a)
+#define MP_BC_LOAD_SUBSCR        (0x2b)
 
 #define MP_BC_STORE_FAST_0       (0x30)
 #define MP_BC_STORE_FAST_1       (0x31)

py/compile.c

@@ -670,7 +670,7 @@ void c_assign_power(compiler_t *comp, mp_parse_node_struct_t *pns, assign_kind_t
                 compile_node(comp, pns1->nodes[0]);
                 if (assign_kind == ASSIGN_AUG_LOAD) {
                     EMIT(dup_top_two);
-                    EMIT_ARG(binary_op, MP_BINARY_OP_SUBSCR);
+                    EMIT(load_subscr);
                 } else {
                     EMIT(store_subscr);
                 }
@@ -2599,7 +2599,7 @@ void compile_trailer_paren(compiler_t *comp, mp_parse_node_struct_t *pns) {
 void compile_trailer_bracket(compiler_t *comp, mp_parse_node_struct_t *pns) {
     // object who's index we want is on top of stack
     compile_node(comp, pns->nodes[0]); // the index
-    EMIT_ARG(binary_op, MP_BINARY_OP_SUBSCR);
+    EMIT(load_subscr);
 }
 
 void compile_trailer_period(compiler_t *comp, mp_parse_node_struct_t *pns) {

py/emit.h

@@ -50,6 +50,7 @@ typedef struct _emit_method_table_t {
     void (*load_attr)(emit_t *emit, qstr qstr);
     void (*load_method)(emit_t *emit, qstr qstr);
     void (*load_build_class)(emit_t *emit);
+    void (*load_subscr)(emit_t *emit);
     void (*store_fast)(emit_t *emit, qstr qstr, int local_num);
     void (*store_deref)(emit_t *emit, qstr qstr, int local_num);
     void (*store_name)(emit_t *emit, qstr qstr);

py/emitbc.c

@@ -477,6 +477,11 @@ STATIC void emit_bc_load_build_class(emit_t *emit) {
     emit_write_byte_code_byte(emit, MP_BC_LOAD_BUILD_CLASS);
 }
 
+STATIC void emit_bc_load_subscr(emit_t *emit) {
+    emit_bc_pre(emit, -1);
+    emit_write_byte_code_byte(emit, MP_BC_LOAD_SUBSCR);
+}
+
 STATIC void emit_bc_store_fast(emit_t *emit, qstr qstr, int local_num) {
     assert(local_num >= 0);
     emit_bc_pre(emit, -1);
@@ -873,6 +878,7 @@ const emit_method_table_t emit_bc_method_table = {
     emit_bc_load_attr,
     emit_bc_load_method,
     emit_bc_load_build_class,
+    emit_bc_load_subscr,
     emit_bc_store_fast,
     emit_bc_store_deref,
     emit_bc_store_name,

py/emitcpy.c

@@ -281,6 +281,13 @@ STATIC void emit_cpy_load_build_class(emit_t *emit) {
     }
 }
 
+STATIC void emit_cpy_load_subscr(emit_t *emit) {
+    emit_pre(emit, -1, 1);
+    if (emit->pass == PASS_3) {
+        printf("BINARY_SUBSCR\n");
+    }
+}
+
 STATIC void emit_cpy_store_fast(emit_t *emit, qstr qstr, int local_num) {
     emit_pre(emit, -1, 3);
     if (emit->pass == PASS_3) {
@@ -555,7 +562,6 @@ STATIC void emit_cpy_binary_op(emit_t *emit, mp_binary_op_t op) {
     }
     if (emit->pass == PASS_3) {
         switch (op) {
-            case MP_BINARY_OP_SUBSCR: printf("BINARY_SUBSCR\n"); break;
             case MP_BINARY_OP_OR: printf("BINARY_OR\n"); break;
             case MP_BINARY_OP_XOR: printf("BINARY_XOR\n"); break;
             case MP_BINARY_OP_AND: printf("BINARY_AND\n"); break;
@@ -817,6 +823,7 @@ const emit_method_table_t emit_cpython_method_table = {
     emit_cpy_load_attr,
     emit_cpy_load_method,
     emit_cpy_load_build_class,
+    emit_cpy_load_subscr,
     emit_cpy_store_fast,
     emit_cpy_store_deref,
     emit_cpy_store_name,

py/emitnative.c

@@ -778,6 +778,18 @@ STATIC void emit_native_load_build_class(emit_t *emit) {
     emit_post_push_reg(emit, VTYPE_PYOBJ, REG_RET);
 }
 
+STATIC void emit_native_load_subscr(emit_t *emit) {
+    vtype_kind_t vtype_lhs, vtype_rhs;
+    emit_pre_pop_reg_reg(emit, &vtype_rhs, REG_ARG_2, &vtype_lhs, REG_ARG_1);
+    if (vtype_lhs == VTYPE_PYOBJ && vtype_rhs == VTYPE_PYOBJ) {
+        emit_call_with_imm_arg(emit, MP_F_OBJ_SUBSCR, mp_obj_subscr, (machine_uint_t)MP_OBJ_SENTINEL, REG_ARG_3);
+        emit_post_push_reg(emit, VTYPE_PYOBJ, REG_RET);
+    } else {
+        printf("ViperTypeError: can't do subscr of types %d and %d\n", vtype_lhs, vtype_rhs);
+        assert(0);
+    }
+}
+
 STATIC void emit_native_store_fast(emit_t *emit, qstr qstr, int local_num) {
     vtype_kind_t vtype;
 #if N_X64
@@ -850,7 +862,7 @@ STATIC void emit_native_store_subscr(emit_t *emit) {
     assert(vtype_index == VTYPE_PYOBJ);
     assert(vtype_base == VTYPE_PYOBJ);
     assert(vtype_value == VTYPE_PYOBJ);
-    emit_call(emit, MP_F_STORE_SUBSCR, mp_store_subscr);
+    emit_call(emit, MP_F_OBJ_SUBSCR, mp_obj_subscr);
 }
 
 STATIC void emit_native_delete_fast(emit_t *emit, qstr qstr, int local_num) {
@@ -882,8 +894,11 @@ STATIC void emit_native_delete_attr(emit_t *emit, qstr qstr) {
 }
 
 STATIC void emit_native_delete_subscr(emit_t *emit) {
-    // not supported
+    vtype_kind_t vtype_index, vtype_base;
-    assert(0);
+    emit_pre_pop_reg_reg(emit, &vtype_index, REG_ARG_2, &vtype_base, REG_ARG_1); // index, base
+    assert(vtype_index == VTYPE_PYOBJ);
+    assert(vtype_base == VTYPE_PYOBJ);
+    emit_call_with_imm_arg(emit, MP_F_OBJ_SUBSCR, mp_obj_subscr, (machine_uint_t)MP_OBJ_NULL, REG_ARG_3);
 }
 
 STATIC void emit_native_dup_top(emit_t *emit) {
@@ -1328,6 +1343,7 @@ const emit_method_table_t EXPORT_FUN(method_table) = {
     emit_native_load_attr,
     emit_native_load_method,
     emit_native_load_build_class,
+    emit_native_load_subscr,
     emit_native_store_fast,
     emit_native_store_deref,
     emit_native_store_name,

py/emitpass1.c

@@ -190,4 +190,5 @@ const emit_method_table_t emit_pass1_method_table = {
     (void*)emit_pass1_dummy,
     (void*)emit_pass1_dummy,
     (void*)emit_pass1_dummy,
+    (void*)emit_pass1_dummy,
 };

py/obj.c

@@ -332,6 +332,24 @@ mp_obj_t mp_obj_len_maybe(mp_obj_t o_in) {
     }
 }
 
+mp_obj_t mp_obj_subscr(mp_obj_t base, mp_obj_t index, mp_obj_t value) {
+    mp_obj_type_t *type = mp_obj_get_type(base);
+    if (type->subscr != NULL) {
+        mp_obj_t ret = type->subscr(base, index, value);
+        if (ret != MP_OBJ_NOT_SUPPORTED) {
+            return ret;
+        }
+        // TODO: call base classes here?
+    }
+    if (value == MP_OBJ_NULL) {
+        nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_TypeError, "'%s' object does not support item deletion", mp_obj_get_type_str(base)));
+    } else if (value == MP_OBJ_SENTINEL) {
+        nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_TypeError, "'%s' object is not subscriptable", mp_obj_get_type_str(base)));
+    } else {
+        nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_TypeError, "'%s' object does not support item assignment", mp_obj_get_type_str(base)));
+    }
+}
+
 // Return input argument. Useful as .getiter for objects which are
 // their own iterators, etc.
 mp_obj_t mp_identity(mp_obj_t self) {

py/obj.h

@@ -28,6 +28,10 @@ typedef struct _mp_obj_base_t mp_obj_base_t;
 
 #define MP_OBJ_SENTINEL ((mp_obj_t)8)
 
+// The NOT_SUPPORTED object is a return value that indicates an unsupported operation.
+
+#define MP_OBJ_NOT_SUPPORTED ((mp_obj_t)16)
+
 // These macros check for small int, qstr or object, and access small int and qstr values
 //  - xxxx...xxx1: a small int, bits 1 and above are the value
 //  - xxxx...xx10: a qstr, bits 2 and above are the value
@@ -165,7 +169,7 @@ typedef mp_obj_t (*mp_unary_op_fun_t)(int op, mp_obj_t);
 typedef mp_obj_t (*mp_binary_op_fun_t)(int op, mp_obj_t, mp_obj_t);
 typedef void (*mp_load_attr_fun_t)(mp_obj_t self_in, qstr attr, mp_obj_t *dest); // for fail, do nothing; for attr, dest[0] = value; for method, dest[0] = method, dest[1] = self
 typedef bool (*mp_store_attr_fun_t)(mp_obj_t self_in, qstr attr, mp_obj_t value); // return true if store succeeded; if value==MP_OBJ_NULL then delete
-typedef bool (*mp_store_item_fun_t)(mp_obj_t self_in, mp_obj_t index, mp_obj_t value); // return true if store succeeded; if value==MP_OBJ_NULL then delete
+typedef mp_obj_t (*mp_subscr_fun_t)(mp_obj_t self_in, mp_obj_t index, mp_obj_t value);
 
 typedef struct _mp_method_t {
     qstr name;
@@ -222,16 +226,13 @@ struct _mp_obj_type_t {
     mp_load_attr_fun_t load_attr;
     mp_store_attr_fun_t store_attr; // if value is MP_OBJ_NULL, then delete that attribute
 
-    // Implements container[index] = val.  If val == MP_OBJ_NULL, then it's a delete.
+    mp_subscr_fun_t subscr;         // implements load, store, delete subscripting
-    // Note that load_item is implemented by binary_op(RT_BINARY_OP_SUBSCR)
+                                    // value=MP_OBJ_NULL means delete, value=MP_OBJ_SENTINEL means load, else store
-    mp_store_item_fun_t store_item;
+                                    // can return MP_OBJ_NOT_SUPPORTED
 
     mp_fun_1_t getiter;
     mp_fun_1_t iternext; // may return MP_OBJ_NULL as an optimisation instead of raising StopIteration() (with no args)
 
-    // Alternatively, pointer(s) to interfaces to save space
-    // in mp_obj_type_t at the expense of extra pointer and extra dereference
-    // when actually used.
     mp_buffer_p_t buffer_p;
     const mp_stream_p_t *stream_p;
 
@@ -242,8 +243,6 @@ struct _mp_obj_type_t {
     /*
     What we might need to add here:
 
-    store_subscr    list dict
-
     len             str tuple list map
     abs             float complex
     hash            bool int none str
@@ -395,6 +394,7 @@ void mp_obj_get_array(mp_obj_t o, uint *len, mp_obj_t **items);
 void mp_obj_get_array_fixed_n(mp_obj_t o, uint len, mp_obj_t **items);
 uint mp_get_index(const mp_obj_type_t *type, machine_uint_t len, mp_obj_t index, bool is_slice);
 mp_obj_t mp_obj_len_maybe(mp_obj_t o_in); /* may return MP_OBJ_NULL */
+mp_obj_t mp_obj_subscr(mp_obj_t base, mp_obj_t index, mp_obj_t val);
 
 // bool
 // TODO make lower case when it has proven itself

py/objarray.c

@@ -112,21 +112,6 @@ STATIC mp_obj_t array_unary_op(int op, mp_obj_t o_in) {
     }
 }
 
-STATIC mp_obj_t array_binary_op(int op, mp_obj_t lhs, mp_obj_t rhs) {
-    mp_obj_array_t *o = lhs;
-    switch (op) {
-        case MP_BINARY_OP_SUBSCR:
-        {
-            uint index = mp_get_index(o->base.type, o->len, rhs, false);
-            return mp_binary_get_val_array(o->typecode, o->items, index);
-        }
-
-        default:
-            // op not supported
-            return MP_OBJ_NULL;
-    }
-}
-
 STATIC mp_obj_t array_append(mp_obj_t self_in, mp_obj_t arg) {
     assert(MP_OBJ_IS_TYPE(self_in, &mp_type_array) || MP_OBJ_IS_TYPE(self_in, &mp_type_bytearray));
     mp_obj_array_t *self = self_in;
@@ -142,15 +127,22 @@ STATIC mp_obj_t array_append(mp_obj_t self_in, mp_obj_t arg) {
 }
 STATIC MP_DEFINE_CONST_FUN_OBJ_2(array_append_obj, array_append);
 
-STATIC bool array_store_item(mp_obj_t self_in, mp_obj_t index_in, mp_obj_t value) {
+STATIC mp_obj_t array_subscr(mp_obj_t self_in, mp_obj_t index_in, mp_obj_t value) {
     if (value == MP_OBJ_NULL) {
         // delete item; does this need to be implemented?
-        return false;
+        return MP_OBJ_NOT_SUPPORTED;
+    } else {
+        mp_obj_array_t *o = self_in;
+        uint index = mp_get_index(o->base.type, o->len, index_in, false);
+        if (value == MP_OBJ_SENTINEL) {
+            // load
+            return mp_binary_get_val_array(o->typecode, o->items, index);
+        } else {
+            // store
+            mp_binary_set_val_array(o->typecode, o->items, index, value);
+            return mp_const_none;
+        }
     }
-    mp_obj_array_t *o = self_in;
-    uint index = mp_get_index(o->base.type, o->len, index_in, false);
-    mp_binary_set_val_array(o->typecode, o->items, index, value);
-    return true;
 }
 
 STATIC machine_int_t array_get_buffer(mp_obj_t o_in, buffer_info_t *bufinfo, int flags) {
@@ -173,8 +165,7 @@ const mp_obj_type_t mp_type_array = {
     .make_new = array_make_new,
     .getiter = array_iterator_new,
     .unary_op = array_unary_op,
-    .binary_op = array_binary_op,
+    .subscr = array_subscr,
-    .store_item = array_store_item,
     .buffer_p = { .get_buffer = array_get_buffer },
     .locals_dict = (mp_obj_t)&array_locals_dict,
 };
@@ -186,8 +177,7 @@ const mp_obj_type_t mp_type_bytearray = {
     .make_new = bytearray_make_new,
     .getiter = array_iterator_new,
     .unary_op = array_unary_op,
-    .binary_op = array_binary_op,
+    .subscr = array_subscr,
-    .store_item = array_store_item,
     .buffer_p = { .get_buffer = array_get_buffer },
     .locals_dict = (mp_obj_t)&array_locals_dict,
 };

py/objdict.c

@@ -84,18 +84,7 @@ STATIC mp_obj_t dict_unary_op(int op, mp_obj_t self_in) {
 STATIC mp_obj_t dict_binary_op(int op, mp_obj_t lhs_in, mp_obj_t rhs_in) {
     mp_obj_dict_t *o = lhs_in;
     switch (op) {
-        case MP_BINARY_OP_SUBSCR:
+        case MP_BINARY_OP_IN: {
-        {
-            // dict load
-            mp_map_elem_t *elem = mp_map_lookup(&o->map, rhs_in, MP_MAP_LOOKUP);
-            if (elem == NULL) {
-                nlr_raise(mp_obj_new_exception_msg(&mp_type_KeyError, "<value>"));
-            } else {
-                return elem->value;
-            }
-        }
-        case MP_BINARY_OP_IN:
-        {
             mp_map_elem_t *elem = mp_map_lookup(&o->map, rhs_in, MP_MAP_LOOKUP);
             return MP_BOOL(elem != NULL);
         }
@@ -129,13 +118,25 @@ STATIC mp_obj_t dict_binary_op(int op, mp_obj_t lhs_in, mp_obj_t rhs_in) {
     }
 }
 
-STATIC bool dict_store_item(mp_obj_t self_in, mp_obj_t index, mp_obj_t value) {
+STATIC mp_obj_t dict_subscr(mp_obj_t self_in, mp_obj_t index, mp_obj_t value) {
     if (value == MP_OBJ_NULL) {
+        // delete
         mp_obj_dict_delete(self_in, index);
+        return mp_const_none;
+    } else if (value == MP_OBJ_SENTINEL) {
+        // load
+        mp_obj_dict_t *self = self_in;
+        mp_map_elem_t *elem = mp_map_lookup(&self->map, index, MP_MAP_LOOKUP);
+        if (elem == NULL) {
+            nlr_raise(mp_obj_new_exception_msg(&mp_type_KeyError, "<value>"));
+        } else {
+            return elem->value;
+        }
     } else {
+        // store
         mp_obj_dict_store(self_in, index, value);
+        return mp_const_none;
     }
-    return true;
 }
 
 /******************************************************************************/
@@ -510,7 +511,7 @@ const mp_obj_type_t mp_type_dict = {
     .make_new = dict_make_new,
     .unary_op = dict_unary_op,
     .binary_op = dict_binary_op,
-    .store_item = dict_store_item,
+    .subscr = dict_subscr,
     .getiter = dict_getiter,
     .locals_dict = (mp_obj_t)&dict_locals_dict,
 };

py/objlist.c

@@ -88,24 +88,7 @@ STATIC mp_obj_t list_unary_op(int op, mp_obj_t self_in) {
 STATIC mp_obj_t list_binary_op(int op, mp_obj_t lhs, mp_obj_t rhs) {
     mp_obj_list_t *o = lhs;
     switch (op) {
-        case MP_BINARY_OP_SUBSCR:
+        case MP_BINARY_OP_ADD: {
-        {
-#if MICROPY_ENABLE_SLICE
-            if (MP_OBJ_IS_TYPE(rhs, &mp_type_slice)) {
-                machine_uint_t start, stop;
-                if (!m_seq_get_fast_slice_indexes(o->len, rhs, &start, &stop)) {
-                    assert(0);
-                }
-                mp_obj_list_t *res = list_new(stop - start);
-                m_seq_copy(res->items, o->items + start, res->len, mp_obj_t);
-                return res;
-            }
-#endif
-            uint index = mp_get_index(o->base.type, o->len, rhs, false);
-            return o->items[index];
-        }
-        case MP_BINARY_OP_ADD:
-        {
             if (!MP_OBJ_IS_TYPE(rhs, &mp_type_list)) {
                 return NULL;
             }
@@ -114,8 +97,7 @@ STATIC mp_obj_t list_binary_op(int op, mp_obj_t lhs, mp_obj_t rhs) {
             m_seq_cat(s->items, o->items, o->len, p->items, p->len, mp_obj_t);
             return s;
         }
-        case MP_BINARY_OP_INPLACE_ADD:
+        case MP_BINARY_OP_INPLACE_ADD: {
-        {
             if (!MP_OBJ_IS_TYPE(rhs, &mp_type_list)) {
                 return NULL;
             }
@@ -144,14 +126,32 @@ STATIC mp_obj_t list_binary_op(int op, mp_obj_t lhs, mp_obj_t rhs) {
     }
 }
 
-STATIC bool list_store_item(mp_obj_t self_in, mp_obj_t index, mp_obj_t value) {
+STATIC mp_obj_t list_subscr(mp_obj_t self_in, mp_obj_t index, mp_obj_t value) {
     if (value == MP_OBJ_NULL) {
+        // delete
         mp_obj_t args[2] = {self_in, index};
         list_pop(2, args);
+        return mp_const_none;
+    } else if (value == MP_OBJ_SENTINEL) {
+        // load
+        mp_obj_list_t *self = self_in;
+#if MICROPY_ENABLE_SLICE
+        if (MP_OBJ_IS_TYPE(index, &mp_type_slice)) {
+            machine_uint_t start, stop;
+            if (!m_seq_get_fast_slice_indexes(self->len, index, &start, &stop)) {
+                assert(0);
+            }
+            mp_obj_list_t *res = list_new(stop - start);
+            m_seq_copy(res->items, self->items + start, res->len, mp_obj_t);
+            return res;
+        }
+#endif
+        uint index_val = mp_get_index(self->base.type, self->len, index, false);
+        return self->items[index_val];
     } else {
         mp_obj_list_store(self_in, index, value);
+        return mp_const_none;
     }
-    return true;
 }
 
 STATIC mp_obj_t list_getiter(mp_obj_t o_in) {
@@ -360,7 +360,7 @@ const mp_obj_type_t mp_type_list = {
     .make_new = list_make_new,
     .unary_op = list_unary_op,
     .binary_op = list_binary_op,
-    .store_item = list_store_item,
+    .subscr = list_subscr,
     .getiter = list_getiter,
     .locals_dict = (mp_obj_t)&list_locals_dict,
 };

py/objnamedtuple.c

@@ -131,6 +131,7 @@ mp_obj_t mp_obj_new_namedtuple_type(qstr name, const char *fields) {
     o->base.binary_op = tuple_binary_op;
     o->base.load_attr = namedtuple_load_attr;
     o->base.store_attr = namedtuple_store_attr;
+    o->base.subscr = tuple_subscr;
     o->base.bases_tuple = (mp_obj_t)&namedtuple_base_tuple;
     o->fields = fields;
     return o;

py/objstr.c

@@ -214,25 +214,6 @@ STATIC const byte *find_subbytes(const byte *haystack, machine_uint_t hlen, cons
 STATIC mp_obj_t str_binary_op(int op, mp_obj_t lhs_in, mp_obj_t rhs_in) {
     GET_STR_DATA_LEN(lhs_in, lhs_data, lhs_len);
     switch (op) {
-        case MP_BINARY_OP_SUBSCR: {
-#if MICROPY_ENABLE_SLICE
-            if (MP_OBJ_IS_TYPE(rhs_in, &mp_type_slice)) {
-                machine_uint_t start, stop;
-                if (!m_seq_get_fast_slice_indexes(lhs_len, rhs_in, &start, &stop)) {
-                    assert(0);
-                }
-                return mp_obj_new_str(lhs_data + start, stop - start, false);
-            }
-#endif
-            mp_obj_type_t *type = mp_obj_get_type(lhs_in);
-            uint index = mp_get_index(type, lhs_len, rhs_in, false);
-            if (type == &mp_type_bytes) {
-                return MP_OBJ_NEW_SMALL_INT((mp_small_int_t)lhs_data[index]);
-            } else {
-                return mp_obj_new_str(lhs_data + index, 1, true);
-            }
-        }
-
         case MP_BINARY_OP_ADD:
         case MP_BINARY_OP_INPLACE_ADD:
             if (MP_OBJ_IS_STR(rhs_in)) {
@@ -307,6 +288,31 @@ STATIC mp_obj_t str_binary_op(int op, mp_obj_t lhs_in, mp_obj_t rhs_in) {
     return MP_OBJ_NULL; // op not supported
 }
 
+STATIC mp_obj_t str_subscr(mp_obj_t self_in, mp_obj_t index, mp_obj_t value) {
+    GET_STR_DATA_LEN(self_in, self_data, self_len);
+    if (value == MP_OBJ_SENTINEL) {
+        // load
+#if MICROPY_ENABLE_SLICE
+        if (MP_OBJ_IS_TYPE(index, &mp_type_slice)) {
+            machine_uint_t start, stop;
+            if (!m_seq_get_fast_slice_indexes(self_len, index, &start, &stop)) {
+                assert(0);
+            }
+            return mp_obj_new_str(self_data + start, stop - start, false);
+        }
+#endif
+        mp_obj_type_t *type = mp_obj_get_type(self_in);
+        uint index_val = mp_get_index(type, self_len, index, false);
+        if (type == &mp_type_bytes) {
+            return MP_OBJ_NEW_SMALL_INT((mp_small_int_t)self_data[index_val]);
+        } else {
+            return mp_obj_new_str(self_data + index_val, 1, true);
+        }
+    } else {
+        return MP_OBJ_NOT_SUPPORTED;
+    }
+}
+
 STATIC mp_obj_t str_join(mp_obj_t self_in, mp_obj_t arg) {
     assert(MP_OBJ_IS_STR(self_in));
 
@@ -1380,6 +1386,7 @@ const mp_obj_type_t mp_type_str = {
     .print = str_print,
     .make_new = str_make_new,
     .binary_op = str_binary_op,
+    .subscr = str_subscr,
     .getiter = mp_obj_new_str_iterator,
     .buffer_p = { .get_buffer = str_get_buffer },
     .locals_dict = (mp_obj_t)&str_locals_dict,
@@ -1392,6 +1399,7 @@ const mp_obj_type_t mp_type_bytes = {
     .print = str_print,
     .make_new = bytes_make_new,
     .binary_op = str_binary_op,
+    .subscr = str_subscr,
     .getiter = mp_obj_new_bytes_iterator,
     .buffer_p = { .get_buffer = str_get_buffer },
     .locals_dict = (mp_obj_t)&str_locals_dict,

py/objtuple.c

@@ -95,22 +95,6 @@ mp_obj_t tuple_unary_op(int op, mp_obj_t self_in) {
 mp_obj_t tuple_binary_op(int op, mp_obj_t lhs, mp_obj_t rhs) {
     mp_obj_tuple_t *o = lhs;
     switch (op) {
-        case MP_BINARY_OP_SUBSCR:
-        {
-#if MICROPY_ENABLE_SLICE
-            if (MP_OBJ_IS_TYPE(rhs, &mp_type_slice)) {
-                machine_uint_t start, stop;
-                if (!m_seq_get_fast_slice_indexes(o->len, rhs, &start, &stop)) {
-                    assert(0);
-                }
-                mp_obj_tuple_t *res = mp_obj_new_tuple(stop - start, NULL);
-                m_seq_copy(res->items, o->items + start, res->len, mp_obj_t);
-                return res;
-            }
-#endif
-            uint index = mp_get_index(o->base.type, o->len, rhs, false);
-            return o->items[index];
-        }
         case MP_BINARY_OP_ADD:
         {
             if (!mp_obj_is_subclass_fast(mp_obj_get_type(rhs), (mp_obj_t)&mp_type_tuple)) {
@@ -144,6 +128,28 @@ mp_obj_t tuple_binary_op(int op, mp_obj_t lhs, mp_obj_t rhs) {
     }
 }
 
+mp_obj_t tuple_subscr(mp_obj_t self_in, mp_obj_t index, mp_obj_t value) {
+    if (value == MP_OBJ_SENTINEL) {
+        // load
+        mp_obj_tuple_t *self = self_in;
+#if MICROPY_ENABLE_SLICE
+        if (MP_OBJ_IS_TYPE(index, &mp_type_slice)) {
+            machine_uint_t start, stop;
+            if (!m_seq_get_fast_slice_indexes(self->len, index, &start, &stop)) {
+                assert(0);
+            }
+            mp_obj_tuple_t *res = mp_obj_new_tuple(stop - start, NULL);
+            m_seq_copy(res->items, self->items + start, res->len, mp_obj_t);
+            return res;
+        }
+#endif
+        uint index_value = mp_get_index(self->base.type, self->len, index, false);
+        return self->items[index_value];
+    } else {
+        return MP_OBJ_NOT_SUPPORTED;
+    }
+}
+
 STATIC mp_obj_t tuple_getiter(mp_obj_t o_in) {
     return mp_obj_new_tuple_iterator(o_in, 0);
 }
@@ -176,6 +182,7 @@ const mp_obj_type_t mp_type_tuple = {
     .make_new = mp_obj_tuple_make_new,
     .unary_op = tuple_unary_op,
     .binary_op = tuple_binary_op,
+    .subscr = tuple_subscr,
     .getiter = tuple_getiter,
     .locals_dict = (mp_obj_t)&tuple_locals_dict,
 };

py/objtuple.h

@@ -7,3 +7,4 @@ typedef struct _mp_obj_tuple_t {
 void tuple_print(void (*print)(void *env, const char *fmt, ...), void *env, mp_obj_t o_in, mp_print_kind_t kind);
 mp_obj_t tuple_unary_op(int op, mp_obj_t self_in);
 mp_obj_t tuple_binary_op(int op, mp_obj_t lhs, mp_obj_t rhs);
+mp_obj_t tuple_subscr(mp_obj_t base, mp_obj_t index, mp_obj_t value);

py/objtype.c

@@ -144,7 +144,6 @@ STATIC mp_obj_t class_unary_op(int op, mp_obj_t self_in) {
 }
 
 STATIC const qstr binary_op_method_name[] = {
-    [MP_BINARY_OP_SUBSCR] = MP_QSTR___getitem__,
     /*
     MP_BINARY_OP_OR,
     MP_BINARY_OP_XOR,
@@ -308,7 +307,7 @@ STATIC bool class_store_attr(mp_obj_t self_in, qstr attr, mp_obj_t value) {
     }
 }
 
-bool class_store_item(mp_obj_t self_in, mp_obj_t index, mp_obj_t value) {
+STATIC mp_obj_t class_subscr(mp_obj_t self_in, mp_obj_t index, mp_obj_t value) {
     mp_obj_class_t *self = self_in;
     mp_obj_t member;
     uint meth_args;
@@ -316,16 +315,26 @@ bool class_store_item(mp_obj_t self_in, mp_obj_t index, mp_obj_t value) {
         // delete item
         member = mp_obj_class_lookup(self->base.type, MP_QSTR___delitem__);
         meth_args = 2;
+    } else if (value == MP_OBJ_SENTINEL) {
+        // load item
+        member = mp_obj_class_lookup(self->base.type, MP_QSTR___getitem__);
+        meth_args = 2;
     } else {
+        // store item
         member = mp_obj_class_lookup(self->base.type, MP_QSTR___setitem__);
         meth_args = 3;
     }
     if (member != MP_OBJ_NULL) {
         mp_obj_t args[3] = {self_in, index, value};
-        mp_call_function_n_kw(member, meth_args, 0, args);
+        // TODO probably need to call class_convert_return_attr, and use mp_call_method_n_kw
-        return true;
+        mp_obj_t ret = mp_call_function_n_kw(member, meth_args, 0, args);
+        if (value == MP_OBJ_SENTINEL) {
+            return ret;
+        } else {
+            return mp_const_none;
+        }
     } else {
-        return false;
+        return MP_OBJ_NOT_SUPPORTED;
     }
 }
 
@@ -464,7 +473,7 @@ mp_obj_t mp_obj_new_type(qstr name, mp_obj_t bases_tuple, mp_obj_t locals_dict)
     o->binary_op = class_binary_op;
     o->load_attr = class_load_attr;
     o->store_attr = class_store_attr;
-    o->store_item = class_store_item;
+    o->subscr = class_subscr;
     o->bases_tuple = bases_tuple;
     o->locals_dict = locals_dict;
     return o;

py/opmethods.c

@@ -7,21 +7,21 @@
 #include "runtime0.h"
 #include "builtin.h"
 
-STATIC mp_obj_t op_getitem(mp_obj_t lhs_in, mp_obj_t rhs_in) {
+STATIC mp_obj_t op_getitem(mp_obj_t self_in, mp_obj_t key_in) {
-    mp_obj_type_t *type = mp_obj_get_type(lhs_in);
+    mp_obj_type_t *type = mp_obj_get_type(self_in);
-    return type->binary_op(MP_BINARY_OP_SUBSCR, lhs_in, rhs_in);
+    return type->subscr(self_in, key_in, MP_OBJ_SENTINEL);
 }
 MP_DEFINE_CONST_FUN_OBJ_2(mp_op_getitem_obj, op_getitem);
 
 STATIC mp_obj_t op_setitem(mp_obj_t self_in, mp_obj_t key_in, mp_obj_t value_in) {
-    mp_store_subscr(self_in, key_in, value_in);
+    mp_obj_type_t *type = mp_obj_get_type(self_in);
-    return mp_const_none;
+    return type->subscr(self_in, key_in, value_in);
 }
 MP_DEFINE_CONST_FUN_OBJ_3(mp_op_setitem_obj, op_setitem);
 
 STATIC mp_obj_t op_delitem(mp_obj_t self_in, mp_obj_t key_in) {
-    mp_store_subscr(self_in, key_in, MP_OBJ_NULL);
+    mp_obj_type_t *type = mp_obj_get_type(self_in);
-    return mp_const_none;
+    return type->subscr(self_in, key_in, MP_OBJ_NULL);
 }
 MP_DEFINE_CONST_FUN_OBJ_2(mp_op_delitem_obj, op_delitem);
 

py/runtime.c

@@ -840,23 +840,6 @@ void mp_store_attr(mp_obj_t base, qstr attr, mp_obj_t value) {
     nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_AttributeError, "'%s' object has no attribute '%s'", mp_obj_get_type_str(base), qstr_str(attr)));
 }
 
-void mp_store_subscr(mp_obj_t base, mp_obj_t index, mp_obj_t value) {
-    DEBUG_OP_printf("store subscr %p[%p] <- %p\n", base, index, value);
-    mp_obj_type_t *type = mp_obj_get_type(base);
-    if (type->store_item != NULL) {
-        bool r = type->store_item(base, index, value);
-        if (r) {
-            return;
-        }
-        // TODO: call base classes here?
-    }
-    if (value == MP_OBJ_NULL) {
-        nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_TypeError, "'%s' object does not support item deletion", mp_obj_get_type_str(base)));
-    } else {
-        nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_TypeError, "'%s' object does not support item assignment", mp_obj_get_type_str(base)));
-    }
-}
-
 mp_obj_t mp_getiter(mp_obj_t o_in) {
     mp_obj_type_t *type = mp_obj_get_type(o_in);
     if (type->getiter != NULL) {
@@ -1120,7 +1103,7 @@ void *const mp_fun_table[MP_F_NUMBER_OF] = {
     mp_load_method,
     mp_store_name,
     mp_store_attr,
-    mp_store_subscr,
+    mp_obj_subscr,
     mp_obj_is_true,
     mp_unary_op,
     mp_binary_op,

py/runtime.h

@@ -48,7 +48,6 @@ mp_obj_t mp_load_attr(mp_obj_t base, qstr attr);
 void mp_load_method(mp_obj_t base, qstr attr, mp_obj_t *dest);
 void mp_load_method_maybe(mp_obj_t base, qstr attr, mp_obj_t *dest);
 void mp_store_attr(mp_obj_t base, qstr attr, mp_obj_t val);
-void mp_store_subscr(mp_obj_t base, mp_obj_t index, mp_obj_t val);
 
 mp_obj_t mp_getiter(mp_obj_t o);
 mp_obj_t mp_iternext_allow_raise(mp_obj_t o); // may return MP_OBJ_NULL instead of raising StopIteration()

py/runtime0.h

@@ -24,7 +24,6 @@ typedef enum {
 } mp_unary_op_t;
 
 typedef enum {
-    MP_BINARY_OP_SUBSCR,
     MP_BINARY_OP_OR,
     MP_BINARY_OP_XOR,
     MP_BINARY_OP_AND,
@@ -75,7 +74,7 @@ typedef enum {
     MP_F_LOAD_METHOD,
     MP_F_STORE_NAME,
     MP_F_STORE_ATTR,
-    MP_F_STORE_SUBSCR,
+    MP_F_OBJ_SUBSCR,
     MP_F_OBJ_IS_TRUE,
     MP_F_UNARY_OP,
     MP_F_BINARY_OP,

py/showbc.c

@@ -182,6 +182,10 @@ void mp_byte_code_print(const byte *ip, int len) {
                 printf("LOAD_BUILD_CLASS");
                 break;
 
+            case MP_BC_LOAD_SUBSCR:
+                printf("LOAD_SUBSCR");
+                break;
+
             case MP_BC_STORE_FAST_0:
                 printf("STORE_FAST_0");
                 break;

py/vm.c

@@ -342,6 +342,11 @@ dispatch_loop:
                     PUSH(mp_load_build_class());
                     DISPATCH();
 
+                ENTRY(MP_BC_LOAD_SUBSCR):
+                    obj1 = POP();
+                    SET_TOP(mp_obj_subscr(TOP(), obj1, MP_OBJ_SENTINEL));
+                    DISPATCH();
+
                 ENTRY(MP_BC_STORE_FAST_0):
                     fastn[0] = POP();
                     DISPATCH();
@@ -381,7 +386,7 @@ dispatch_loop:
                     DISPATCH();
 
                 ENTRY(MP_BC_STORE_SUBSCR):
-                    mp_store_subscr(sp[-1], sp[0], sp[-2]);
+                    mp_obj_subscr(sp[-1], sp[0], sp[-2]);
                     sp -= 3;
                     DISPATCH();
 

py/vmentrytable.h

@@ -21,6 +21,7 @@ static void* entry_table[256] = {
     [MP_BC_LOAD_ATTR] = &&entry_MP_BC_LOAD_ATTR,
     [MP_BC_LOAD_METHOD] = &&entry_MP_BC_LOAD_METHOD,
     [MP_BC_LOAD_BUILD_CLASS] = &&entry_MP_BC_LOAD_BUILD_CLASS,
+    [MP_BC_LOAD_SUBSCR] = &&entry_MP_BC_LOAD_SUBSCR,
     [MP_BC_STORE_FAST_0] = &&entry_MP_BC_STORE_FAST_0,
     [MP_BC_STORE_FAST_1] = &&entry_MP_BC_STORE_FAST_1,
     [MP_BC_STORE_FAST_2] = &&entry_MP_BC_STORE_FAST_2,