Exemplo n.º 1
0
        protected override void EmitRead(ProtoBuf.Compiler.CompilerContext ctx, ProtoBuf.Compiler.Local valueFrom)
        {
            Type listType;
#if NO_GENERICS
            listType = typeof(BasicList);
#else
            listType = ctx.MapType(typeof(System.Collections.Generic.List<>)).MakeGenericType(itemType);
#endif
            Type expected = ExpectedType;
            using (Compiler.Local oldArr = AppendToCollection ? ctx.GetLocalWithValue(expected, valueFrom) : null)
            using (Compiler.Local newArr = new Compiler.Local(ctx, expected))
            using (Compiler.Local list = new Compiler.Local(ctx, listType))
            {
                ctx.EmitCtor(listType);
                ctx.StoreValue(list);
                ListDecorator.EmitReadList(ctx, list, Tail, listType.GetMethod("Add"), packedWireType, false);

                // leave this "using" here, as it can share the "FieldNumber" local with EmitReadList
                using(Compiler.Local oldLen = AppendToCollection ? new ProtoBuf.Compiler.Local(ctx, ctx.MapType(typeof(int))) : null) {
                    Type[] copyToArrayInt32Args = new Type[] { ctx.MapType(typeof(Array)), ctx.MapType(typeof(int)) };

                    if (AppendToCollection)
                    {
                        ctx.LoadLength(oldArr, true);
                        ctx.CopyValue();
                        ctx.StoreValue(oldLen);

                        ctx.LoadAddress(list, listType);
                        ctx.LoadValue(listType.GetProperty("Count"));
                        ctx.Add();
                        ctx.CreateArray(itemType, null); // length is on the stack
                        ctx.StoreValue(newArr);

                        ctx.LoadValue(oldLen);
                        Compiler.CodeLabel nothingToCopy = ctx.DefineLabel();
                        ctx.BranchIfFalse(nothingToCopy, true);
                        ctx.LoadValue(oldArr);
                        ctx.LoadValue(newArr);
                        ctx.LoadValue(0); // index in target

                        ctx.EmitCall(expected.GetMethod("CopyTo", copyToArrayInt32Args));
                        ctx.MarkLabel(nothingToCopy);

                        ctx.LoadValue(list);
                        ctx.LoadValue(newArr);
                        ctx.LoadValue(oldLen);
                        
                    }
                    else
                    {
                        ctx.LoadAddress(list, listType);
                        ctx.LoadValue(listType.GetProperty("Count"));
                        ctx.CreateArray(itemType, null);
                        ctx.StoreValue(newArr);

                        ctx.LoadAddress(list, listType);
                        ctx.LoadValue(newArr);
                        ctx.LoadValue(0);
                    }

                    copyToArrayInt32Args[0] = expected; // // prefer: CopyTo(T[], int)
                    MethodInfo copyTo = listType.GetMethod("CopyTo", copyToArrayInt32Args);
                    if (copyTo == null)
                    { // fallback: CopyTo(Array, int)
                        copyToArrayInt32Args[1] = ctx.MapType(typeof(Array));
                        copyTo = listType.GetMethod("CopyTo", copyToArrayInt32Args);
                    }
                    ctx.EmitCall(copyTo);
                }
                ctx.LoadValue(newArr);
            }


        }