Enable fast-path parsing for repeated Cord fields.

ClaytonKnittel · copybara-github · commit 75afd7fd613c · 2025-08-08T14:18:18.000-07:00
PiperOrigin-RevId: 792758858
diff --git a/src/google/protobuf/generated_message_tctable_gen.cc b/src/google/protobuf/generated_message_tctable_gen.cc
@@ -151,7 +151,7 @@ TailCallTableInfo::FastFieldInfo::Field MakeFastFieldEntry(
 
 #define PROTOBUF_PICK_STRING_FUNCTION(fn)                                 \
   (field->cpp_string_type() == FieldDescriptor::CppStringType::kCord      \
-       ? PROTOBUF_PICK_FUNCTION(fn##cS)                                   \
+       ? PROTOBUF_PICK_REPEATABLE_FUNCTION(fn##c)                         \
    : field->cpp_string_type() == FieldDescriptor::CppStringType::kView && \
            options.use_micro_string                                       \
        ? PROTOBUF_PICK_FUNCTION(fn##mS)                                   \
@@ -739,27 +739,6 @@ bool IsFieldTypeEligibleForFastParsing(const FieldDescriptor* field) {
     return false;
   }
 
-  switch (field->type()) {
-      // Some bytes fields can be handled on fast path.
-    case FieldDescriptor::TYPE_STRING:
-    case FieldDescriptor::TYPE_BYTES: {
-      auto ctype = field->cpp_string_type();
-      if (ctype == FieldDescriptor::CppStringType::kString ||
-          ctype == FieldDescriptor::CppStringType::kView) {
-        // strings are fine...
-      } else if (ctype == FieldDescriptor::CppStringType::kCord) {
-        // Cords are worth putting into the fast table, if they're not repeated
-        if (field->is_repeated()) return false;
-      } else {
-        return false;
-      }
-      break;
-    }
-
-    default:
-      break;
-  }
-
   // The largest tag that can be read by the tailcall parser is two bytes
   // when varint-coded. This allows 14 bits for the numeric tag value:
   //   byte 0   byte 1
diff --git a/src/google/protobuf/generated_message_tctable_impl.h b/src/google/protobuf/generated_message_tctable_impl.h
@@ -351,8 +351,8 @@ inline void AlignFail(std::integral_constant<size_t, 1>,
   PROTOBUF_TC_PARSE_FUNCTION_LIST_REPEATED(FastU)                 \
   PROTOBUF_TC_PARSE_FUNCTION_LIST_SINGLE(FastBi)                  \
   PROTOBUF_TC_PARSE_FUNCTION_LIST_SINGLE(FastUi)                  \
-  PROTOBUF_TC_PARSE_FUNCTION_LIST_SINGLE(FastBc)                  \
-  PROTOBUF_TC_PARSE_FUNCTION_LIST_SINGLE(FastUc)                  \
+  PROTOBUF_TC_PARSE_FUNCTION_LIST_REPEATED(FastBc)                \
+  PROTOBUF_TC_PARSE_FUNCTION_LIST_REPEATED(FastUc)                \
   PROTOBUF_TC_PARSE_FUNCTION_LIST_SINGLE(FastBm)                  \
   PROTOBUF_TC_PARSE_FUNCTION_LIST_SINGLE(FastUm)                  \
   PROTOBUF_TC_PARSE_FUNCTION_LIST_REPEATED(FastGd)                \
@@ -648,6 +648,15 @@ class PROTOBUF_EXPORT TcParser final {
   PROTOBUF_NOINLINE PROTOBUF_CC static const char* FastUcS2(
       PROTOBUF_TC_PARAM_DECL);
 
+  PROTOBUF_NOINLINE PROTOBUF_CC static const char* FastBcR1(
+      PROTOBUF_TC_PARAM_DECL);
+  PROTOBUF_NOINLINE PROTOBUF_CC static const char* FastBcR2(
+      PROTOBUF_TC_PARAM_DECL);
+  PROTOBUF_NOINLINE PROTOBUF_CC static const char* FastUcR1(
+      PROTOBUF_TC_PARAM_DECL);
+  PROTOBUF_NOINLINE PROTOBUF_CC static const char* FastUcR2(
+      PROTOBUF_TC_PARAM_DECL);
+
   PROTOBUF_NOINLINE PROTOBUF_CC static const char* FastBmS1(
       PROTOBUF_TC_PARAM_DECL);
   PROTOBUF_NOINLINE PROTOBUF_CC static const char* FastBmS2(
@@ -1013,6 +1022,8 @@ class PROTOBUF_EXPORT TcParser final {
   PROTOBUF_CC static inline const char* SingularString(PROTOBUF_TC_PARAM_DECL);
   template <typename TagType, typename FieldType, Utf8Type utf8>
   PROTOBUF_CC static inline const char* RepeatedString(PROTOBUF_TC_PARAM_DECL);
+  template <typename TagType, Utf8Type utf8>
+  PROTOBUF_CC static inline const char* RepeatedCord(PROTOBUF_TC_PARAM_DECL);
 
   static inline const char* ParseRepeatedStringOnce(
       const char* ptr, SerialArena* serial_arena, ParseContext* ctx,
diff --git a/src/google/protobuf/generated_message_tctable_lite.cc b/src/google/protobuf/generated_message_tctable_lite.cc
@@ -1861,6 +1861,19 @@ PROTOBUF_NOINLINE const char* TcParser::FastUR2(PROTOBUF_TC_PARAM_DECL) {
       PROTOBUF_TC_PARAM_PASS);
 }
 
+PROTOBUF_NOINLINE const char* TcParser::FastBcR1(PROTOBUF_TC_PARAM_DECL) {
+  PROTOBUF_MUSTTAIL return MiniParse(PROTOBUF_TC_PARAM_NO_DATA_PASS);
+}
+PROTOBUF_NOINLINE const char* TcParser::FastBcR2(PROTOBUF_TC_PARAM_DECL) {
+  PROTOBUF_MUSTTAIL return MiniParse(PROTOBUF_TC_PARAM_NO_DATA_PASS);
+}
+PROTOBUF_NOINLINE const char* TcParser::FastUcR1(PROTOBUF_TC_PARAM_DECL) {
+  PROTOBUF_MUSTTAIL return MiniParse(PROTOBUF_TC_PARAM_NO_DATA_PASS);
+}
+PROTOBUF_NOINLINE const char* TcParser::FastUcR2(PROTOBUF_TC_PARAM_DECL) {
+  PROTOBUF_MUSTTAIL return MiniParse(PROTOBUF_TC_PARAM_NO_DATA_PASS);
+}
+
 //////////////////////////////////////////////////////////////////////////////
 // Mini parsing
 //////////////////////////////////////////////////////////////////////////////
