Assume HasHasbit() for SingularMessage and !HasHasbit() for OneofMessage.

PiperOrigin-RevId: 612347702

src/google/protobuf/compiler/cpp/field_generators/message_field.cc

@@ -309,42 +309,20 @@ void SingularMessage::GenerateInlineAccessorDefinitions(io::Printer* p) const {
 }
 
 void SingularMessage::GenerateClearingCode(io::Printer* p) const {
-  if (!has_hasbit_) {
-    // If we don't have has-bits, message presence is indicated only by ptr !=
-    // nullptr. Thus on clear, we need to delete the object.
-    p->Emit(
-        R"cc(
-          if (GetArena() == nullptr && $field_$ != nullptr) {
-            delete $field_$;
-          }
-          $field_$ = nullptr;
-        )cc");
-  } else {
-    p->Emit(
-        R"cc(
-          if ($field_$ != nullptr) $field_$->Clear();
-        )cc");
-  }
+  ABSL_CHECK(has_hasbit_);
+  p->Emit(
+      R"cc(
+        if ($field_$ != nullptr) $field_$->Clear();
+      )cc");
 }
 
 void SingularMessage::GenerateMessageClearingCode(io::Printer* p) const {
-  if (!has_hasbit_) {
-    // If we don't have has-bits, message presence is indicated only by ptr !=
-    // nullptr. Thus on clear, we need to delete the object.
-    p->Emit(
-        R"cc(
-          if (GetArena() == nullptr && $field_$ != nullptr) {
-            delete $field_$;
-          }
-          $field_$ = nullptr;
-        )cc");
-  } else {
-    p->Emit(
-        R"cc(
-          $DCHK$($field_$ != nullptr);
-          $field_$->Clear();
-        )cc");
-  }
+  ABSL_CHECK(has_hasbit_);
+  p->Emit(
+      R"cc(
+        $DCHK$($field_$ != nullptr);
+        $field_$->Clear();
+      )cc");
 }
 
 bool SingularMessage::RequiresArena(GeneratorFunction function) const {
@@ -407,21 +385,13 @@ void SingularMessage::GenerateDestructorCode(io::Printer* p) const {
 using internal::cpp::HasHasbit;
 
 void SingularMessage::GenerateCopyConstructorCode(io::Printer* p) const {
-  if (has_hasbit_) {
-    p->Emit(R"cc(
-      if ((from.$has_hasbit$) != 0) {
-        _this->$field_$ =
-            $superclass$::CopyConstruct<$Submsg$>(arena, *from.$field_$);
-      }
-    )cc");
-  } else {
-    p->Emit(R"cc(
-      if (from._internal_has_$name$()) {
-        _this->$field_$ =
-            $superclass$::CopyConstruct<$Submsg$>(arena, *from.$field_$);
-      }
-    )cc");
-  }
+  ABSL_CHECK(has_hasbit_);
+  p->Emit(R"cc(
+    if ((from.$has_hasbit$) != 0) {
+      _this->$field_$ =
+          $superclass$::CopyConstruct<$Submsg$>(arena, *from.$field_$);
+    }
+  )cc");
 }
 
 void SingularMessage::GenerateSerializeWithCachedSizesToArray(
@@ -505,6 +475,7 @@ class OneofMessage : public SingularMessage {
   void GenerateSwappingCode(io::Printer* p) const override;
   void GenerateDestructorCode(io::Printer* p) const override;
   void GenerateConstructorCode(io::Printer* p) const override;
+  void GenerateCopyConstructorCode(io::Printer* p) const override;
   void GenerateIsInitialized(io::Printer* p) const override;
   void GenerateMergingCode(io::Printer* p) const override;
   bool RequiresArena(GeneratorFunction func) const override;
@@ -646,6 +617,16 @@ void OneofMessage::GenerateConstructorCode(io::Printer* p) const {
   // space only when this field is used.
 }
 
+void OneofMessage::GenerateCopyConstructorCode(io::Printer* p) const {
+  ABSL_CHECK(!has_hasbit_);
+  p->Emit(R"cc(
+    if (from._internal_has_$name$()) {
+      _this->$field_$ =
+          $superclass$::CopyConstruct<$Submsg$>(arena, *from.$field_$);
+    }
+  )cc");
+}
+
 void OneofMessage::GenerateIsInitialized(io::Printer* p) const {
   if (!has_required_) return;