py: Fix typing of viper locals; allow default types in annotation.

py/compile.c

@@ -3017,7 +3017,7 @@ STATIC void compile_scope_func_annotations(compiler_t *comp, mp_parse_node_t pn)
                 qstr arg_type = MP_PARSE_NODE_LEAF_ARG(pn_annotation);
                 EMIT_ARG(set_native_type, MP_EMIT_NATIVE_TYPE_ARG, id_info->local_num, arg_type);
             } else {
-                compile_syntax_error(comp, pn_annotation, "annotation must be an identifier");
+                compile_syntax_error(comp, pn_annotation, "parameter annotation must be an identifier");
             }
         }
         #endif // MICROPY_EMIT_NATIVE
@@ -3155,17 +3155,20 @@ STATIC void compile_scope(compiler_t *comp, scope_t *scope, pass_kind_t pass) {
             apply_to_single_or_list(comp, pns->nodes[1], PN_typedargslist, compile_scope_func_annotations);
 
             // pns->nodes[2] is return/whole function annotation
-            #if MICROPY_EMIT_NATIVE
-            if (scope->emit_options == MP_EMIT_OPT_VIPER) {
-                // nodes[2] can be null or a test-expr
-                if (MP_PARSE_NODE_IS_ID(pns->nodes[2])) {
-                    qstr ret_type = MP_PARSE_NODE_LEAF_ARG(pns->nodes[2]);
-                    EMIT_ARG(set_native_type, MP_EMIT_NATIVE_TYPE_RETURN, 0, ret_type);
-                } else {
-                    compile_syntax_error(comp, pns->nodes[2], "annotation must be an identifier");
+            mp_parse_node_t pn_annotation = pns->nodes[2];
+            if (!MP_PARSE_NODE_IS_NULL(pn_annotation)) {
+                #if MICROPY_EMIT_NATIVE
+                if (scope->emit_options == MP_EMIT_OPT_VIPER) {
+                    // nodes[2] can be null or a test-expr
+                    if (MP_PARSE_NODE_IS_ID(pn_annotation)) {
+                        qstr ret_type = MP_PARSE_NODE_LEAF_ARG(pn_annotation);
+                        EMIT_ARG(set_native_type, MP_EMIT_NATIVE_TYPE_RETURN, 0, ret_type);
+                    } else {
+                        compile_syntax_error(comp, pn_annotation, "return annotation must be an identifier");
+                    }
                 }
+                #endif // MICROPY_EMIT_NATIVE
             }
-            #endif // MICROPY_EMIT_NATIVE
         }
 
         compile_node(comp, pns->nodes[3]); // 3 is function body
@@ -3625,7 +3628,7 @@ mp_obj_t mp_compile(mp_parse_node_t pn, qstr source_file, uint emit_opt, bool is
                     comp->emit_method_table = &emit_native_thumb_method_table;
 #endif
                     comp->emit = emit_native;
-                    comp->emit_method_table->set_native_type(comp->emit, MP_EMIT_NATIVE_TYPE_ENABLE, s->emit_options == MP_EMIT_OPT_VIPER, 0);
+                    EMIT_ARG(set_native_type, MP_EMIT_NATIVE_TYPE_ENABLE, s->emit_options == MP_EMIT_OPT_VIPER, 0);
 
                     // native emitters need an extra pass to compute stack size
                     compile_scope(comp, s, MP_PASS_STACK_SIZE);

py/emitnative.c

@@ -241,12 +241,19 @@ STATIC void emit_native_start_pass(emit_t *emit, pass_kind_t pass, scope_t *scop
 
     // set default type for return and arguments
     emit->return_vtype = VTYPE_PYOBJ;
-    for (int i = 0; i < emit->local_vtype_alloc; i++) {
+    for (mp_uint_t i = 0; i < emit->scope->num_pos_args; i++) {
         emit->local_vtype[i] = VTYPE_PYOBJ;
     }
-    for (int i = 0; i < emit->stack_info_alloc; i++) {
+
+    // local variables begin unbound, and have unknown type
+    for (mp_uint_t i = emit->scope->num_pos_args; i < emit->local_vtype_alloc; i++) {
+        emit->local_vtype[i] = VTYPE_UNBOUND;
+    }
+
+    // values on stack begin unbound
+    for (mp_uint_t i = 0; i < emit->stack_info_alloc; i++) {
         emit->stack_info[i].kind = STACK_VALUE;
-        emit->stack_info[i].vtype = VTYPE_PYOBJ;
+        emit->stack_info[i].vtype = VTYPE_UNBOUND;
     }
 
 #if N_X64
@@ -844,7 +851,6 @@ STATIC void emit_native_load_subscr(emit_t *emit) {
         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);
     }
 }
 
@@ -1212,7 +1218,7 @@ STATIC void emit_native_binary_op(emit_t *emit, mp_binary_op_t op) {
         emit_post_push_reg(emit, VTYPE_PYOBJ, REG_RET);
     } else {
         printf("ViperTypeError: can't do binary op between types %d and %d\n", vtype_lhs, vtype_rhs);
-        assert(0);
+        emit_post_push_reg(emit, VTYPE_PYOBJ, REG_RET);
     }
 }
 

tests/micropython/viper.py

@@ -10,6 +10,25 @@ def f(x:int, y:int) -> int:
 def g(x:object, y:object) -> object:
     return x + y
 
+# a local (should have automatic type int)
+@micropython.viper
+def h(x:int) -> int:
+    y = 4
+    return x + y
+
+# without type annotation, types should default to object
+@micropython.viper
+def i(x, y):
+    return x * y
+
+# a for loop
+@micropython.viper
+def viper_sum(a:int, b:int) -> int:
+    total = 0
+    for x in range(a, b):
+        total += x
+    return total
+
 # this doesn't work at the moment
 #@micropython.viper
 #def g() -> uint:
@@ -17,4 +36,6 @@ def g(x:object, y:object) -> object:
 
 print(f(1, 2))
 print(g(1, 2))
-#print(h())
+print(h(3))
+print(i(4, 5))
+print(viper_sum(10, 10000))

tests/micropython/viper.py.exp

@@ -1,2 +1,5 @@
 6
 3
+7
+20
+49994955