8339113: AccessFlags can be u2 in metadata

src/hotspot/share/oops/fieldInfo.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2023, 2024, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2023, 2025, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -34,7 +34,7 @@ void FieldInfo::print(outputStream* os, ConstantPool* cp) {
                 name_index(), name(cp)->as_utf8(),
                 signature_index(), signature(cp)->as_utf8(),
                 offset(),
-                access_flags().as_unsigned_short(),
+                access_flags().as_field_flags(),
                 field_flags().as_uint(),
                 initializer_index(),
                 generic_signature_index(),
@@ -97,7 +97,7 @@ Array<u1>* FieldInfoStream::create_FieldInfoStream(GrowableArray<FieldInfo>* fie
     assert(fi_ref->name_index() == fi.name_index(), "Must be");
     assert(fi_ref->signature_index() == fi.signature_index(), "Must be");
     assert(fi_ref->offset() == fi.offset(), "Must be");
-    assert(fi_ref->access_flags().as_unsigned_short() == fi.access_flags().as_unsigned_short(), "Must be");
+    assert(fi_ref->access_flags().as_field_flags() == fi.access_flags().as_field_flags(), "Must be");
     assert(fi_ref->field_flags().as_uint() == fi.field_flags().as_uint(), " Must be");
     if(fi_ref->field_flags().is_initialized()) {
       assert(fi_ref->initializer_index() == fi.initializer_index(), "Must be");

src/hotspot/share/oops/fieldInfo.inline.hpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2023, 2024, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2023, 2025, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -73,7 +73,7 @@ inline void Mapper<CON>::map_field_info(const FieldInfo& fi) {
   _consumer->accept_uint(fi.name_index());
   _consumer->accept_uint(fi.signature_index());
   _consumer->accept_uint(fi.offset());
-  _consumer->accept_uint(fi.access_flags().as_unsigned_short());
+  _consumer->accept_uint(fi.access_flags().as_field_flags());
   _consumer->accept_uint(fi.field_flags().as_uint());
   if(fi.field_flags().has_any_optionals()) {
     if (fi.field_flags().is_initialized()) {

src/hotspot/share/oops/instanceKlass.cpp

@@ -3340,7 +3340,7 @@ InstanceKlass* InstanceKlass::compute_enclosing_class(bool* inner_is_member, TRA
 }
 
 u2 InstanceKlass::compute_modifier_flags() const {
-  u2 access = access_flags().as_unsigned_short();
+  u2 access = access_flags().as_class_flags();
 
   // But check if it happens to be member class.
   InnerClassesIterator iter(this);

src/hotspot/share/oops/method.cpp

@@ -1653,7 +1653,7 @@ void Method::init_intrinsic_id(vmSymbolID klass_id) {
     return;
   }
 
-  u2 flags = access_flags().as_unsigned_short();
+  u2 flags = access_flags().as_method_flags();
   vmIntrinsics::ID id = vmIntrinsics::find_id(klass_id, name_id, sig_id, flags);
   if (id != vmIntrinsics::_none) {
     set_intrinsic_id(id);

src/hotspot/share/prims/jvm.cpp

@@ -1817,7 +1817,7 @@ JVM_ENTRY(jint, JVM_GetClassAccessFlags(JNIEnv *env, jclass cls))
   }
 
   Klass* k = java_lang_Class::as_Klass(mirror);
-  return k->access_flags().as_unsigned_short();
+  return k->access_flags().as_class_flags();
 }
 JVM_END
 

src/hotspot/share/prims/jvmtiEnv.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2003, 2024, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2003, 2025, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -3149,7 +3149,7 @@ jvmtiError
 JvmtiEnv::GetFieldModifiers(fieldDescriptor* fdesc_ptr, jint* modifiers_ptr) {
 
   AccessFlags resultFlags = fdesc_ptr->access_flags();
-  jint result = resultFlags.as_unsigned_short();
+  jint result = resultFlags.as_field_flags();
   *modifiers_ptr = result;
 
   return JVMTI_ERROR_NONE;

src/hotspot/share/prims/jvmtiRedefineClasses.cpp

@@ -1005,8 +1005,8 @@ jvmtiError VM_RedefineClasses::compare_and_normalize_class_versions(
   }
 
   // Check whether class modifiers are the same.
-  u2 old_flags = the_class->access_flags().as_unsigned_short();
-  u2 new_flags = scratch_class->access_flags().as_unsigned_short();
+  u2 old_flags = the_class->access_flags().as_class_flags();
+  u2 new_flags = scratch_class->access_flags().as_class_flags();
   if (old_flags != new_flags) {
     log_info(redefine, class, normalize)
         ("redefined class %s modifiers change error: modifiers changed from %d to %d.",
@@ -1147,8 +1147,8 @@ jvmtiError VM_RedefineClasses::compare_and_normalize_class_versions(
     switch (method_was) {
     case matched:
       // methods match, be sure modifiers do too
-      old_flags = k_old_method->access_flags().as_unsigned_short();
-      new_flags = k_new_method->access_flags().as_unsigned_short();
+      old_flags = k_old_method->access_flags().as_method_flags();
+      new_flags = k_new_method->access_flags().as_method_flags();
       if ((old_flags ^ new_flags) & ~(JVM_ACC_NATIVE)) {
         log_info(redefine, class, normalize)
           ("redefined class %s  method %s modifiers error: modifiers changed from %d to %d",

src/hotspot/share/prims/methodHandles.cpp

@@ -404,7 +404,7 @@ bool MethodHandles::is_method_handle_invoke_name(Klass* klass, Symbol* name) {
   Method* m = iklass->find_method(name, poly_sig);
   if (m != nullptr) {
     int required = JVM_ACC_NATIVE | JVM_ACC_VARARGS;
-    int flags = m->access_flags().as_unsigned_short();
+    int flags = m->access_flags().as_method_flags();
     if ((flags & required) == required) {
       return true;
     }
@@ -417,7 +417,7 @@ bool MethodHandles::is_method_handle_invoke_name(Klass* klass, Symbol* name) {
   for (; ms < me; ms++) {
     Method* m = iklass->methods()->at(ms);
     int required = JVM_ACC_NATIVE | JVM_ACC_VARARGS;
-    int flags = m->access_flags().as_unsigned_short();
+    int flags = m->access_flags().as_method_flags();
     if ((flags & required) == required && ArgumentCount(m->signature()).size() == 1) {
       return true;
     }
@@ -522,7 +522,7 @@ bool MethodHandles::is_signature_polymorphic_public_name(Klass* klass, Symbol* n
     for (; ms < me; ms++) {
       Method* m = iklass->methods()->at(ms);
       int required = JVM_ACC_NATIVE | JVM_ACC_VARARGS | JVM_ACC_PUBLIC;
-      int flags = m->access_flags().as_unsigned_short();
+      int flags = m->access_flags().as_method_flags();
       if ((flags & required) == required && ArgumentCount(m->signature()).size() == 1) {
         return true;
       }

src/hotspot/share/utilities/accessFlags.hpp

@@ -64,11 +64,6 @@ class AccessFlags {
   // get as integral value
   u2 as_unsigned_short() const         { return _flags; }
 
-  // Initialization
-  void set_field_flags(u2 flags)      {
-    assert((flags & JVM_RECOGNIZED_FIELD_MODIFIERS) == flags, "only recognized flags");
-    _flags = (flags & JVM_RECOGNIZED_FIELD_MODIFIERS);
-  }
   void set_flags(u2 flags)            { _flags = flags; }
 
  private:
@@ -83,9 +78,20 @@ class AccessFlags {
  public:
   inline friend AccessFlags accessFlags_from(u2 flags);
 
-  u2 as_method_flags() const { return _flags & JVM_RECOGNIZED_METHOD_MODIFIERS; }
-  u2 as_field_flags() const  { return _flags & JVM_RECOGNIZED_FIELD_MODIFIERS; }
-  u2 as_class_flags() const  { return _flags & JVM_RECOGNIZED_CLASS_MODIFIERS; }
+  u2 as_method_flags() const {
+    assert((_flags & JVM_RECOGNIZED_METHOD_MODIFIERS) == _flags, "only recognized flags");
+    return _flags;
+  }
+
+  u2 as_field_flags() const  {
+    assert((_flags & JVM_RECOGNIZED_FIELD_MODIFIERS) == _flags, "only recognized flags");
+    return _flags;
+  }
+
+  u2 as_class_flags() const  {
+    assert((_flags & JVM_RECOGNIZED_CLASS_MODIFIERS) == _flags, "only recognized flags");
+    return _flags;
+  }
 
   // Printing/debugging
 #if INCLUDE_JVMTI