Use ToTagDispatch, unless we know for sure that we don't have more data

available.
This prevents flushing hasbits unnecessarily, and enables the fast dispatch to the next field instead of returning back to ParseLoop to do it.

PiperOrigin-RevId: 540717028

src/google/protobuf/generated_message_tctable_lite.cc

@@ -633,8 +633,11 @@ PROTOBUF_ALWAYS_INLINE const char* TcParser::RepeatedFixed(
   do {
     field.Add(UnalignedLoad<LayoutType>(ptr + sizeof(TagType)));
     ptr += sizeof(TagType) + sizeof(LayoutType);
-  } while (ctx->DataAvailable(ptr) && UnalignedLoad<TagType>(ptr) == tag);
-  PROTOBUF_MUSTTAIL return ToParseLoop(PROTOBUF_TC_PARAM_NO_DATA_PASS);
+    if (PROTOBUF_PREDICT_FALSE(!ctx->DataAvailable(ptr))) {
+      PROTOBUF_MUSTTAIL return ToParseLoop(PROTOBUF_TC_PARAM_NO_DATA_PASS);
+    }
+  } while (UnalignedLoad<TagType>(ptr) == tag);
+  PROTOBUF_MUSTTAIL return ToTagDispatch(PROTOBUF_TC_PARAM_NO_DATA_PASS);
 }
 
 PROTOBUF_NOINLINE const char* TcParser::FastF32R1(PROTOBUF_TC_PARAM_DECL) {
@@ -974,11 +977,11 @@ PROTOBUF_ALWAYS_INLINE const char* TcParser::RepeatedVarint(
       PROTOBUF_MUSTTAIL return Error(PROTOBUF_TC_PARAM_NO_DATA_PASS);
     }
     field.Add(ZigZagDecodeHelper<FieldType, zigzag>(tmp));
-    if (!ctx->DataAvailable(ptr)) {
-      break;
+    if (PROTOBUF_PREDICT_FALSE(!ctx->DataAvailable(ptr))) {
+      PROTOBUF_MUSTTAIL return ToParseLoop(PROTOBUF_TC_PARAM_NO_DATA_PASS);
     }
   } while (UnalignedLoad<TagType>(ptr) == expected_tag);
-  PROTOBUF_MUSTTAIL return ToParseLoop(PROTOBUF_TC_PARAM_NO_DATA_PASS);
+  PROTOBUF_MUSTTAIL return ToTagDispatch(PROTOBUF_TC_PARAM_NO_DATA_PASS);
 }
 
 PROTOBUF_NOINLINE const char* TcParser::FastV8R1(PROTOBUF_TC_PARAM_DECL) {
@@ -1201,11 +1204,12 @@ const char* TcParser::RepeatedEnum(PROTOBUF_TC_PARAM_DECL) {
       PROTOBUF_MUSTTAIL return FastUnknownEnumFallback(PROTOBUF_TC_PARAM_PASS);
     }
     field.Add(static_cast<int32_t>(tmp));
-    if (!ctx->DataAvailable(ptr)) {
-      break;
+    if (PROTOBUF_PREDICT_FALSE(!ctx->DataAvailable(ptr))) {
+      PROTOBUF_MUSTTAIL return ToParseLoop(PROTOBUF_TC_PARAM_NO_DATA_PASS);
     }
   } while (UnalignedLoad<TagType>(ptr) == expected_tag);
-  PROTOBUF_MUSTTAIL return ToParseLoop(PROTOBUF_TC_PARAM_NO_DATA_PASS);
+
+  PROTOBUF_MUSTTAIL return ToTagDispatch(PROTOBUF_TC_PARAM_NO_DATA_PASS);
 }
 
 const TcParser::UnknownFieldOps& TcParser::GetUnknownFieldOps(
@@ -1346,10 +1350,12 @@ const char* TcParser::RepeatedEnumSmallRange(PROTOBUF_TC_PARAM_DECL) {
     }
     field.Add(static_cast<int32_t>(v));
     ptr += sizeof(TagType) + 1;
-    if (PROTOBUF_PREDICT_FALSE(!ctx->DataAvailable(ptr))) break;
+    if (PROTOBUF_PREDICT_FALSE(!ctx->DataAvailable(ptr))) {
+      PROTOBUF_MUSTTAIL return ToParseLoop(PROTOBUF_TC_PARAM_NO_DATA_PASS);
+    }
   } while (UnalignedLoad<TagType>(ptr) == expected_tag);
 
-  PROTOBUF_MUSTTAIL return ToParseLoop(PROTOBUF_TC_PARAM_NO_DATA_PASS);
+  PROTOBUF_MUSTTAIL return ToTagDispatch(PROTOBUF_TC_PARAM_NO_DATA_PASS);
 }
 
 PROTOBUF_NOINLINE const char* TcParser::FastEr0R1(PROTOBUF_TC_PARAM_DECL) {
@@ -1502,17 +1508,19 @@ PROTOBUF_ALWAYS_INLINE const char* TcParser::SingularString(
 #ifdef NDEBUG
     case kUtf8ValidateOnly:
 #endif
-      PROTOBUF_MUSTTAIL return ToParseLoop(PROTOBUF_TC_PARAM_NO_DATA_PASS);
+      break;
     default:
       if (PROTOBUF_PREDICT_TRUE(IsValidUTF8(field))) {
-        PROTOBUF_MUSTTAIL return ToParseLoop(PROTOBUF_TC_PARAM_NO_DATA_PASS);
+        break;
       }
       ReportFastUtf8Error(FastDecodeTag(saved_tag), table);
       if (utf8 == kUtf8) {
         PROTOBUF_MUSTTAIL return Error(PROTOBUF_TC_PARAM_NO_DATA_PASS);
       }
-      PROTOBUF_MUSTTAIL return ToParseLoop(PROTOBUF_TC_PARAM_NO_DATA_PASS);
+      break;
   }
+
+  PROTOBUF_MUSTTAIL return ToTagDispatch(PROTOBUF_TC_PARAM_NO_DATA_PASS);
 }
 
 PROTOBUF_NOINLINE const char* TcParser::FastBS1(PROTOBUF_TC_PARAM_DECL) {
@@ -1632,10 +1640,12 @@ PROTOBUF_ALWAYS_INLINE const char* TcParser::RepeatedString(
       if (PROTOBUF_PREDICT_FALSE(ptr == nullptr || !validate_last_string())) {
         PROTOBUF_MUSTTAIL return Error(PROTOBUF_TC_PARAM_NO_DATA_PASS);
       }
-      if (!ctx->DataAvailable(ptr)) break;
+      if (PROTOBUF_PREDICT_FALSE(!ctx->DataAvailable(ptr))) {
+        PROTOBUF_MUSTTAIL return ToParseLoop(PROTOBUF_TC_PARAM_NO_DATA_PASS);
+      }
     } while (UnalignedLoad<TagType>(ptr) == expected_tag);
   }
-  PROTOBUF_MUSTTAIL return ToParseLoop(PROTOBUF_TC_PARAM_NO_DATA_PASS);
+  PROTOBUF_MUSTTAIL return ToTagDispatch(PROTOBUF_TC_PARAM_NO_DATA_PASS);
 }
 
 PROTOBUF_NOINLINE const char* TcParser::FastBR1(PROTOBUF_TC_PARAM_DECL) {
@@ -2196,7 +2206,7 @@ PROTOBUF_NOINLINE const char* TcParser::MpString(PROTOBUF_TC_PARAM_DECL) {
   if (ptr == nullptr || !is_valid) {
     PROTOBUF_MUSTTAIL return Error(PROTOBUF_TC_PARAM_NO_DATA_PASS);
   }
-  PROTOBUF_MUSTTAIL return ToParseLoop(PROTOBUF_TC_PARAM_NO_DATA_PASS);
+  PROTOBUF_MUSTTAIL return ToTagDispatch(PROTOBUF_TC_PARAM_NO_DATA_PASS);
 }
 
 PROTOBUF_ALWAYS_INLINE const char* TcParser::ParseRepeatedStringOnce(
@@ -2273,7 +2283,7 @@ PROTOBUF_NOINLINE const char* TcParser::MpRepeatedString(
 #endif
   }
 
-  PROTOBUF_MUSTTAIL return ToParseLoop(PROTOBUF_TC_PARAM_NO_DATA_PASS);
+  PROTOBUF_MUSTTAIL return ToTagDispatch(PROTOBUF_TC_PARAM_NO_DATA_PASS);
 }