[vala/staging: 1/2] vala: Cache async parameter lists of coroutine methods

[Rico Tzschichholz <ricotz src gnome org>]

commit dec92cb1ab3e1f4cda796cd5efb703efbae51d98
Author: Rico Tzschichholz <ricotz ubuntu com>
Date:   Fri Nov 13 23:53:15 2020 +0100

    vala: Cache async parameter lists of coroutine methods

 vala/valamethod.vala | 34 ++++++++++++++++++++++------------
 1 file changed, 22 insertions(+), 12 deletions(-)
---
diff --git a/vala/valamethod.vala b/vala/valamethod.vala
index 9a0fc2aff..d4771681a 100644
--- a/vala/valamethod.vala
+++ b/vala/valamethod.vala
@@ -186,6 +186,8 @@ public class Vala.Method : Subroutine, Callable {
        public bool is_async_callback { get; set; }
 
        private List<Parameter> parameters = new ArrayList<Parameter> ();
+       private List<Parameter>? async_begin_parameters;
+       private List<Parameter>? async_end_parameters;
        private List<Expression> preconditions;
        private List<Expression> postconditions;
        private DataType _return_type;
@@ -1200,18 +1202,23 @@ public class Vala.Method : Subroutine, Callable {
                return callback_method;
        }
 
-       public List<Parameter> get_async_begin_parameters () {
+       public unowned List<Parameter> get_async_begin_parameters () {
                assert (this.coroutine);
 
+               if (async_begin_parameters != null) {
+                       return async_begin_parameters;
+               }
+
+               async_begin_parameters = new ArrayList<Parameter> ();
+
                var glib_ns = CodeContext.get ().root.scope.lookup ("GLib");
 
-               var params = new ArrayList<Parameter> ();
                Parameter ellipsis = null;
                foreach (var param in parameters) {
                        if (param.ellipsis) {
                                ellipsis = param;
                        } else if (param.direction == ParameterDirection.IN) {
-                               params.add (param);
+                               async_begin_parameters.add (param);
                        }
                }
 
@@ -1225,35 +1232,38 @@ public class Vala.Method : Subroutine, Callable {
                callback_param.initializer.target_type = callback_type.copy ();
                callback_param.set_attribute_double ("CCode", "pos", -1);
                callback_param.set_attribute_double ("CCode", "delegate_target_pos", -0.9);
-
-               params.add (callback_param);
+               async_begin_parameters.add (callback_param);
 
                if (ellipsis != null) {
-                       params.add (ellipsis);
+                       async_begin_parameters.add (ellipsis);
                }
 
-               return params;
+               return async_begin_parameters;
        }
 
-       public List<Parameter> get_async_end_parameters () {
+       public unowned List<Parameter> get_async_end_parameters () {
                assert (this.coroutine);
 
-               var params = new ArrayList<Parameter> ();
+               if (async_end_parameters != null) {
+                       return async_end_parameters;
+               }
+
+               async_end_parameters = new ArrayList<Parameter> ();
 
                var glib_ns = CodeContext.get ().root.scope.lookup ("GLib");
                var result_type = new ObjectType ((ObjectTypeSymbol) glib_ns.scope.lookup ("AsyncResult"));
 
                var result_param = new Parameter ("_res_", result_type);
                result_param.set_attribute_double ("CCode", "pos", get_attribute_double ("CCode", 
"async_result_pos", 0.1));
-               params.add (result_param);
+               async_end_parameters.add (result_param);
 
                foreach (var param in parameters) {
                        if (param.direction == ParameterDirection.OUT) {
-                               params.add (param);
+                               async_end_parameters.add (param);
                        }
                }
 
-               return params;
+               return async_end_parameters;
        }
 
        public void add_captured_variable (LocalVariable local) {