public void EmitRead(SerializerCodeGen g, EmitReadMetaDelegate readNextMeta, Action prepareInstance, Action <Local> add)
        {
            if (readNextMeta == null)
            {
                readNextMeta = (s, f) => f();
            }
            using (g.ctx.StartDebugBlockAuto(this))
            {
                WireType packedWireType      = _packedWireTypeForRead;
                bool     packedAllowedStatic = (!_protoCompatibility || packedWireType != WireType.None);
                using (var packed = packedAllowedStatic ? g.ctx.Local(typeof(bool)) : null)
                    using (var token = g.ctx.Local(typeof(SubItemToken)))
                        using (var fieldNumber = _protoCompatibility ? g.ctx.Local(typeof(int)):null)
                            using (var loop = g.ctx.Local(typeof(bool)))
                            {
                                if (!fieldNumber.IsNullRef())
                                {
                                    g.Assign(fieldNumber, g.ReaderFunc.FieldNumber());
                                }
                                if (packedAllowedStatic)
                                {
                                    g.Assign(packed, g.ReaderFunc.WireType() == WireType.String);
                                }

                                bool subItemNeededStatic = !_protoCompatibility;

                                if (subItemNeededStatic || packedAllowedStatic)
                                {
                                    if (!subItemNeededStatic)
                                    {
                                        g.If(packed);
                                    }
                                    g.Assign(token, g.ReaderFunc.StartSubItem());
                                    if (!subItemNeededStatic)
                                    {
                                        g.End();
                                    }
                                }

                                g.ctx.MarkDebug("ProtoCompatibility: " + _protoCompatibility);
                                if (_protoCompatibility)
                                {
                                    // this is not an error that we don't wait for the first item
                                    // if field is present there is at least one element

                                    prepareInstance?.Invoke();

                                    if (packedAllowedStatic)
                                    {
                                        g.If(packed);
                                        {
                                            g.While(g.ReaderFunc.HasSubValue_bool(packedWireType));
                                            {
                                                EmitReadElementContent(g, add);
                                            }
                                            g.End();
                                        }
                                        g.Else();
                                    }

                                    g.DoWhile();
                                    {
                                        EmitReadElementContent(g, add);
                                    }
                                    g.EndDoWhile(g.ReaderFunc.TryReadFieldHeader_bool(fieldNumber));

                                    if (packedAllowedStatic)
                                    {
                                        g.End();
                                    }
                                }
                                else
                                {
                                    var breakLabel = g.DefineLabel();

                                    g.DoWhile();
                                    {
                                        g.Assign(loop, false);

                                        readNextMeta(
                                            () =>
                                        {
                                            using (g.ctx.StartDebugBlockAuto(this, "readNextMeta.OnSuccess"))
                                            {
                                                g.Assign(loop, true);
                                            }
                                        },
                                            () =>
                                        {
                                            using (g.ctx.StartDebugBlockAuto(this, "readNextMeta.OnFail"))
                                            {
                                                g.If(!g.ReaderFunc.TryReadFieldHeader_bool(FieldItem));
                                                {
                                                    g.If(g.ReaderFunc.ReadFieldHeader_int() == 0);
                                                    {
                                                        g.Goto(breakLabel);
                                                    }
                                                    g.End();

                                                    g.Reader.SkipField();
                                                    g.Assign(loop, true);
                                                }
                                                g.End();
                                            }
                                        });
                                    }
                                    g.EndDoWhile(loop);

                                    g.MarkLabel(breakLabel);

                                    prepareInstance?.Invoke();

                                    g.If(g.ReaderFunc.FieldNumber() == FieldItem);
                                    {
                                        g.If(packed);
                                        {
                                            using (var packedWireTypeDynamic = g.ctx.Local(typeof(WireType)))
                                            {
                                                g.Assign(packedWireTypeDynamic, g.ReaderFunc.WireType());
                                                g.DoWhile();
                                                {
                                                    EmitReadElementContent(g, add);
                                                }
                                                g.EndDoWhile(g.ReaderFunc.HasSubValue_bool(packedWireTypeDynamic));
                                            }
                                        }
                                        g.Else();
                                        {
                                            g.DoWhile();
                                            {
                                                EmitReadElementContent(g, add);
                                            }
                                            g.EndDoWhile(g.ReaderFunc.TryReadFieldHeader_bool(FieldItem));
                                        }
                                        g.End();
                                    }
                                    g.End();
                                }

                                if (subItemNeededStatic || packedAllowedStatic)
                                {
                                    if (!subItemNeededStatic)
                                    {
                                        g.If(packed);
                                    }
                                    g.Reader.EndSubItem(token);
                                    if (!subItemNeededStatic)
                                    {
                                        g.End();
                                    }
                                }
                            }
            }
        }