Mark shared parser error branches as unlikely

Author: Altren

include/rfl/parsing/NamedTupleParser.hpp

@@ -389,12 +389,12 @@ struct NamedTupleParser {
     const auto reader = ViewReaderType(&_r, _view, &found, &set, &errors);
     if constexpr (_no_field_names) {
       const auto err = _r.read_array(reader, _obj_or_arr);
-      if (err) {
+      if (err) [[unlikely]] {
         return std::make_pair(set, err);
       }
     } else {
       const auto err = _r.read_object(reader, _obj_or_arr);
-      if (err) {
+      if (err) [[unlikely]] {
         return std::make_pair(set, err);
       }
     }
@@ -405,7 +405,7 @@ struct NamedTupleParser {
     if constexpr (internal::fail_fast_v<ProcessorsType>) {
       return std::make_pair(set, std::move(errors).error());
     } else {
-      if (errors.size() != 0) {
+      if (errors.size() != 0) [[unlikely]] {
         return std::make_pair(set, to_single_error_message(errors));
       }
       return std::make_pair(set, std::optional<Error>());
@@ -419,12 +419,12 @@ struct NamedTupleParser {
     const auto reader = ViewReaderWithDefaultType(&_r, _view, &errors);
     if constexpr (_no_field_names) {
       const auto err = _r.read_array(reader, _obj_or_arr);
-      if (err) {
+      if (err) [[unlikely]] {
         return err;
       }
     } else {
       const auto err = _r.read_object(reader, _obj_or_arr);
-      if (err) {
+      if (err) [[unlikely]] {
         return err;
       }
     }
@@ -438,7 +438,7 @@ struct NamedTupleParser {
     if constexpr (internal::fail_fast_v<ProcessorsType>) {
       return std::move(errors).error();
     } else {
-      if (errors.size() != 0) {
+      if (errors.size() != 0) [[unlikely]] {
         return to_single_error_message(errors);
       }
       return std::nullopt;

include/rfl/parsing/ViewReader.hpp

@@ -105,7 +105,7 @@ class ViewReader {
       std::get<i>(*_found) = true;
       *_already_assigned = true;
       auto res = Parser<R, W, T, ProcessorsType>::read(_r, _var);
-      if (!res) {
+      if (!res) [[unlikely]] {
         constexpr auto name = FieldType::name();
         std::stringstream stream;
         stream << "Failed to parse field '" << name
@@ -141,7 +141,7 @@ class ViewReader {
       std::get<_pos>(*_found) = true;
     }
     auto res = Parser<R, W, T, ProcessorsType>::read(_r, _var);
-    if (!res) {
+    if (!res) [[unlikely]] {
       std::stringstream stream;
       stream << "Failed to parse field '" << _current_name
              << "': " << res.error().what();