py/compile: Only compile function annotations if really needed.

Function annotations are only needed when the native emitter is enabled
and when the current scope is emitted in viper mode.  All other times
the annotations can be skipped completely.

py/compile.c

@@ -2786,6 +2786,7 @@ STATIC void compile_scope_lambda_param(compiler_t *comp, mp_parse_node_t pn) {
     compile_scope_func_lambda_param(comp, pn, PN_varargslist_name, PN_varargslist_star, PN_varargslist_dbl_star);
 }
 
+#if MICROPY_EMIT_NATIVE
 STATIC void compile_scope_func_annotations(compiler_t *comp, mp_parse_node_t pn) {
     if (!MP_PARSE_NODE_IS_STRUCT(pn)) {
         // no annotation
@@ -2816,22 +2817,19 @@ STATIC void compile_scope_func_annotations(compiler_t *comp, mp_parse_node_t pn)
     mp_parse_node_t pn_annotation = pns->nodes[1];
 
     if (!MP_PARSE_NODE_IS_NULL(pn_annotation)) {
-        #if MICROPY_EMIT_NATIVE
         qstr param_name = MP_PARSE_NODE_LEAF_ARG(pns->nodes[0]);
         id_info_t *id_info = scope_find(comp->scope_cur, param_name);
         assert(id_info != NULL);
 
-        if (comp->scope_cur->emit_options == MP_EMIT_OPT_VIPER) {
-            if (MP_PARSE_NODE_IS_ID(pn_annotation)) {
-                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, "parameter annotation must be an identifier");
-            }
+        if (MP_PARSE_NODE_IS_ID(pn_annotation)) {
+            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, "parameter annotation must be an identifier");
         }
-        #endif // MICROPY_EMIT_NATIVE
     }
 }
+#endif // MICROPY_EMIT_NATIVE
 
 STATIC void compile_scope_comp_iter(compiler_t *comp, mp_parse_node_t pn_iter, mp_parse_node_t pn_inner_expr, int l_top, int for_depth) {
     tail_recursion:
@@ -2954,8 +2952,11 @@ STATIC void compile_scope(compiler_t *comp, scope_t *scope, pass_kind_t pass) {
         if (comp->pass == MP_PASS_SCOPE) {
             comp->have_star = false;
             apply_to_single_or_list(comp, pns->nodes[1], PN_typedargslist, compile_scope_func_param);
-        } else {
+        }
+        #if MICROPY_EMIT_NATIVE
+        else if (scope->emit_options == MP_EMIT_OPT_VIPER) {
             // compile annotations; only needed on latter compiler passes
+            // only needed for viper emitter
 
             // argument annotations
             apply_to_single_or_list(comp, pns->nodes[1], PN_typedargslist, compile_scope_func_annotations);
@@ -2963,19 +2964,16 @@ STATIC void compile_scope(compiler_t *comp, scope_t *scope, pass_kind_t pass) {
             // pns->nodes[2] is return/whole function annotation
             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");
-                    }
+                // 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
         // emit return if it wasn't the last opcode