8339113: AccessFlags can be u2 in metadata

src/hotspot/share/ci/ciFlags.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1999, 2021, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1999, 2024, 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
@@ -92,5 +92,5 @@ void ciFlags::print_member_flags(outputStream* st) {
 // ------------------------------------------------------------------
 // ciFlags::print
 void ciFlags::print(outputStream* st) {
-  st->print(" flags=%x", _flags);
+  st->print(" flags=%x", _flags.as_unsigned_short());
 }

src/hotspot/share/ci/ciFlags.hpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1999, 2023, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1999, 2024, 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
@@ -26,7 +26,6 @@
 #define SHARE_CI_CIFLAGS_HPP
 
 #include "ci/ciClassList.hpp"
-#include "jvm_constants.h"
 #include "utilities/accessFlags.hpp"
 #include "utilities/ostream.hpp"
 
@@ -39,37 +38,37 @@ class ciFlags {
   friend class ciField;
   friend class ciMethod;
 
-  jint _flags;
+  AccessFlags _flags;
   bool _stable;
-  bool _intialized_final_update;
+  bool _initialized_final_update;
 
-  ciFlags() :_flags(0), _stable(false), _intialized_final_update(false) { }
+  ciFlags() :_flags(0), _stable(false), _initialized_final_update(false) { }
   ciFlags(AccessFlags flags, bool is_stable = false, bool is_initialized_final_update = false) :
-    _flags(flags.as_int()), _stable(is_stable), _intialized_final_update(is_initialized_final_update) { }
+    _flags(flags), _stable(is_stable), _initialized_final_update(is_initialized_final_update) { }
 
 public:
   // Java access flags
-  bool is_public               () const { return (_flags & JVM_ACC_PUBLIC                    ) != 0; }
-  bool is_private              () const { return (_flags & JVM_ACC_PRIVATE                   ) != 0; }
-  bool is_protected            () const { return (_flags & JVM_ACC_PROTECTED                 ) != 0; }
-  bool is_static               () const { return (_flags & JVM_ACC_STATIC                    ) != 0; }
-  bool is_final                () const { return (_flags & JVM_ACC_FINAL                     ) != 0; }
-  bool is_synchronized         () const { return (_flags & JVM_ACC_SYNCHRONIZED              ) != 0; }
-  bool is_super                () const { return (_flags & JVM_ACC_SUPER                     ) != 0; }
-  bool is_volatile             () const { return (_flags & JVM_ACC_VOLATILE                  ) != 0; }
-  bool is_transient            () const { return (_flags & JVM_ACC_TRANSIENT                 ) != 0; }
-  bool is_native               () const { return (_flags & JVM_ACC_NATIVE                    ) != 0; }
-  bool is_interface            () const { return (_flags & JVM_ACC_INTERFACE                 ) != 0; }
-  bool is_abstract             () const { return (_flags & JVM_ACC_ABSTRACT                  ) != 0; }
+  bool is_public               () const { return _flags.is_public();       }
+  bool is_private              () const { return _flags.is_private();      }
+  bool is_protected            () const { return _flags.is_protected();    }
+  bool is_static               () const { return _flags.is_static();       }
+  bool is_final                () const { return _flags.is_final();        }
+  bool is_synchronized         () const { return _flags.is_synchronized(); }
+  bool is_super                () const { return _flags.is_super();        }
+  bool is_volatile             () const { return _flags.is_volatile();     }
+  bool is_transient            () const { return _flags.is_transient();    }
+  bool is_native               () const { return _flags.is_native();       }
+  bool is_interface            () const { return _flags.is_interface();    }
+  bool is_abstract             () const { return _flags.is_abstract();     }
   bool is_stable               () const { return _stable; }
   // In case the current object represents a field, return true if
   // the field is modified outside of instance initializer methods
   // (or class/initializer methods if the field is static) and false
   // otherwise.
-  bool has_initialized_final_update() const { return _intialized_final_update; };
+  bool has_initialized_final_update() const { return _initialized_final_update; };
 
   // Conversion
-  jint   as_int()                      { return _flags; }
+  jint   as_int()                      { return _flags.as_unsigned_short(); }
 
   void print_klass_flags(outputStream* st = tty);
   void print_member_flags(outputStream* st = tty);

src/hotspot/share/ci/ciKlass.cpp

@@ -222,7 +222,7 @@ jint ciKlass::modifier_flags() {
 jint ciKlass::access_flags() {
   assert(is_loaded(), "not loaded");
   GUARDED_VM_ENTRY(
-    return get_Klass()->access_flags().as_int();
+    return get_Klass()->access_flags().as_unsigned_short();
   )
 }
 

src/hotspot/share/classfile/classFileParser.cpp

@@ -2998,7 +2998,7 @@ u2 ClassFileParser::parse_classfile_inner_classes_attribute(const ClassFileStrea
     inner_classes->at_put(index++, inner_class_info_index);
     inner_classes->at_put(index++, outer_class_info_index);
     inner_classes->at_put(index++, inner_name_index);
-    inner_classes->at_put(index++, inner_access_flags.as_int());
+    inner_classes->at_put(index++, inner_access_flags.as_unsigned_short());
   }
 
   // Check for circular and duplicate entries.
@@ -5336,7 +5336,7 @@ ClassFileParser::ClassFileParser(ClassFileStream* stream,
   assert(_stream != nullptr, "invariant");
   assert(_stream->buffer() == _stream->current(), "invariant");
   assert(_class_name != nullptr, "invariant");
-  assert(0 == _access_flags.as_int(), "invariant");
+  assert(0 == _access_flags.as_unsigned_short(), "invariant");
 
   // Figure out whether we can skip format checking (matching classic VM behavior)
   _need_verify = Verifier::should_verify_for(_loader_data->class_loader());

src/hotspot/share/classfile/javaClasses.cpp

@@ -3169,7 +3169,7 @@ void java_lang_ClassFrameInfo::serialize_offsets(SerializeClosure* f) {
 #endif
 
 static int get_flags(const methodHandle& m) {
-  int flags = (jushort)( m->access_flags().as_int() & JVM_RECOGNIZED_METHOD_MODIFIERS );
+  int flags = m->access_flags().as_method_flags();
   if (m->is_object_initializer()) {
     flags |= java_lang_invoke_MemberName::MN_IS_CONSTRUCTOR;
   } else {
@@ -5537,7 +5537,7 @@ int InjectedField::compute_offset() {
   ik->print();
   tty->print_cr("all fields:");
   for (AllFieldStream fs(ik); !fs.done(); fs.next()) {
-    tty->print_cr("  name: %s, sig: %s, flags: %08x", fs.name()->as_C_string(), fs.signature()->as_C_string(), fs.access_flags().as_int());
+    tty->print_cr("  name: %s, sig: %s, flags: %08x", fs.name()->as_C_string(), fs.signature()->as_C_string(), fs.access_flags().as_unsigned_short());
   }
 #endif //PRODUCT
   vm_exit_during_initialization("Invalid layout of well-known class: use -Xlog:class+load=info to see the origin of the problem class");

src/hotspot/share/interpreter/linkResolver.cpp

@@ -583,7 +583,7 @@ void LinkResolver::check_method_accessability(Klass* ref_klass,
       resolved_klass->is_array_klass()) {
     // We need to change "protected" to "public".
     assert(flags.is_protected(), "clone not protected?");
-    jint new_flags = flags.as_int();
+    u2 new_flags = flags.as_unsigned_short();
     new_flags = new_flags & (~JVM_ACC_PROTECTED);
     new_flags = new_flags | JVM_ACC_PUBLIC;
     flags.set_flags(new_flags);

src/hotspot/share/jfr/leakprofiler/chains/edgeUtils.cpp

@@ -72,7 +72,7 @@ const Symbol* EdgeUtils::field_name(const Edge& edge, jshort* modifiers) {
     JavaFieldStream jfs(ik);
     while (!jfs.done()) {
       if (offset == jfs.offset()) {
-        *modifiers = jfs.access_flags().as_int();
+        *modifiers = jfs.access_flags().as_unsigned_short();
         return jfs.name();
       }
       jfs.next();

src/hotspot/share/jfr/recorder/checkpoint/types/jfrTypeSet.cpp

@@ -227,9 +227,9 @@ static traceid method_id(KlassPtr klass, MethodPtr method) {
 }
 
 template <typename T>
-static s4 get_flags(const T* ptr) {
+static u2 get_flags(const T* ptr) {
   assert(ptr != nullptr, "invariant");
-  return ptr->access_flags().as_int();
+  return ptr->access_flags().as_unsigned_short();
 }
 
 // Same as JVM_GetClassModifiers
@@ -968,7 +968,7 @@ static int write_method(JfrCheckpointWriter* writer, MethodPtr method, bool leak
   writer->write(artifact_id(klass));
   writer->write(mark_symbol(method->name(), leakp));
   writer->write(mark_symbol(method->signature(), leakp));
-  writer->write(static_cast<u2>(get_flags(method)));
+  writer->write(get_flags(method));
   writer->write(get_visibility(method));
   return 1;
 }

src/hotspot/share/jvmci/jvmciCompilerToVM.cpp

@@ -1000,7 +1000,7 @@ C2V_VMENTRY_NULL(jobject, resolveFieldInPool, (JNIEnv* env, jobject, ARGUMENT_PA
   if (info.is_null() || JVMCIENV->get_length(info) != 4) {
     JVMCI_ERROR_NULL("info must not be null and have a length of 4");
   }
-  JVMCIENV->put_int_at(info, 0, fd.access_flags().as_int());
+  JVMCIENV->put_int_at(info, 0, fd.access_flags().as_unsigned_short());
   JVMCIENV->put_int_at(info, 1, fd.offset());
   JVMCIENV->put_int_at(info, 2, fd.index());
   JVMCIENV->put_int_at(info, 3, fd.field_flags().as_uint());

src/hotspot/share/jvmci/jvmciEnv.cpp

@@ -1592,7 +1592,7 @@ JVMCIObject JVMCIEnv::new_FieldInfo(FieldInfo* fieldinfo, JVMCI_TRAPS) {
     HotSpotJVMCI::FieldInfo::set_nameIndex(JVMCIENV, obj_h(), (jint)fieldinfo->name_index());
     HotSpotJVMCI::FieldInfo::set_signatureIndex(JVMCIENV, obj_h(), (jint)fieldinfo->signature_index());
     HotSpotJVMCI::FieldInfo::set_offset(JVMCIENV, obj_h(), (jint)fieldinfo->offset());
-    HotSpotJVMCI::FieldInfo::set_classfileFlags(JVMCIENV, obj_h(), (jint)fieldinfo->access_flags().as_int());
+    HotSpotJVMCI::FieldInfo::set_classfileFlags(JVMCIENV, obj_h(), (jint)fieldinfo->access_flags().as_unsigned_short());
     HotSpotJVMCI::FieldInfo::set_internalFlags(JVMCIENV, obj_h(), (jint)fieldinfo->field_flags().as_uint());
     HotSpotJVMCI::FieldInfo::set_initializerIndex(JVMCIENV, obj_h(), (jint)fieldinfo->initializer_index());
     return wrap(obj_h());
@@ -1603,7 +1603,7 @@ JVMCIObject JVMCIEnv::new_FieldInfo(FieldInfo* fieldinfo, JVMCI_TRAPS) {
                                       (jint)fieldinfo->name_index(),
                                       (jint)fieldinfo->signature_index(),
                                       (jint)fieldinfo->offset(),
-                                      (jint)fieldinfo->access_flags().as_int(),
+                                      (jint)fieldinfo->access_flags().as_unsigned_short(),
                                       (jint)fieldinfo->field_flags().as_uint(),
                                       (jint)fieldinfo->initializer_index());
 

src/hotspot/share/oops/fieldInfo.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2023, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2023, 2024, 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_int(),
+                access_flags().as_unsigned_short(),
                 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_int() == fi.access_flags().as_int(), "Must be");
+    assert(fi_ref->access_flags().as_unsigned_short() == fi.access_flags().as_unsigned_short(), "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, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2023, 2024, 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_int());
+  _consumer->accept_uint(fi.access_flags().as_unsigned_short());
   _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_int();
+  u2 access = access_flags().as_unsigned_short();
 
   // But check if it happens to be member class.
   InnerClassesIterator iter(this);

src/hotspot/share/oops/instanceKlass.hpp

@@ -391,7 +391,7 @@ class InstanceKlass: public Klass {
 
  public:
   int     field_offset      (int index) const { return field(index).offset(); }
-  int     field_access_flags(int index) const { return field(index).access_flags().as_int(); }
+  int     field_access_flags(int index) const { return field(index).access_flags().as_unsigned_short(); }
   FieldInfo::FieldFlags field_flags(int index) const { return field(index).field_flags(); }
   FieldStatus field_status(int index)   const { return fields_status()->at(index); }
   inline Symbol* field_name        (int index) const;

src/hotspot/share/oops/method.cpp

@@ -1652,7 +1652,7 @@ void Method::init_intrinsic_id(vmSymbolID klass_id) {
       && sig_id == vmSymbolID::NO_SID) {
     return;
   }
-  jshort flags = access_flags().as_int();
+  jshort flags = checked_cast<jshort>(access_flags().as_unsigned_short());
 
   vmIntrinsics::ID id = vmIntrinsics::find_id(klass_id, name_id, sig_id, flags);
   if (id != vmIntrinsics::_none) {
@@ -2300,7 +2300,7 @@ void Method::print_on(outputStream* st) const {
   st->print   (" - method holder:     "); method_holder()->print_value_on(st); st->cr();
   st->print   (" - constants:         " PTR_FORMAT " ", p2i(constants()));
   constants()->print_value_on(st); st->cr();
-  st->print   (" - access:            0x%x  ", access_flags().as_int()); access_flags().print_on(st); st->cr();
+  st->print   (" - access:            0x%x  ", access_flags().as_unsigned_short()); access_flags().print_on(st); st->cr();
   st->print   (" - flags:             0x%x  ", _flags.as_int()); _flags.print_on(st); st->cr();
   st->print   (" - name:              ");    name()->print_value_on(st); st->cr();
   st->print   (" - signature:         ");    signature()->print_value_on(st); st->cr();

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_int();
+  return k->access_flags().as_unsigned_short();
 }
 JVM_END
 
@@ -2460,14 +2460,17 @@ JVM_ENTRY(jint, JVM_GetMethodIxModifiers(JNIEnv *env, jclass cls, int method_ind
   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
   k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
   Method* method = InstanceKlass::cast(k)->methods()->at(method_index);
-  return method->access_flags().as_int() & JVM_RECOGNIZED_METHOD_MODIFIERS;
+  return method->access_flags().as_method_flags();
 JVM_END
 
 
 JVM_ENTRY(jint, JVM_GetFieldIxModifiers(JNIEnv *env, jclass cls, int field_index))
   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
   k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
-  return InstanceKlass::cast(k)->field_access_flags(field_index) & JVM_RECOGNIZED_FIELD_MODIFIERS;
+  u2 field_access_flags = InstanceKlass::cast(k)->field_access_flags(field_index);
+  // This & should be unnecessary.
+  assert((field_access_flags & JVM_RECOGNIZED_FIELD_MODIFIERS) == field_access_flags, "already masked");
+  return field_access_flags;
 JVM_END
 
 
@@ -2657,7 +2660,7 @@ JVM_ENTRY(jint, JVM_GetCPFieldModifiers(JNIEnv *env, jclass cls, int cp_index, j
       InstanceKlass* ik = InstanceKlass::cast(k_called);
       for (JavaFieldStream fs(ik); !fs.done(); fs.next()) {
         if (fs.name() == name && fs.signature() == signature) {
-          return fs.access_flags().as_int() & JVM_RECOGNIZED_FIELD_MODIFIERS;
+          return fs.access_flags().as_field_flags();
         }
       }
       return -1;
@@ -2686,7 +2689,7 @@ JVM_ENTRY(jint, JVM_GetCPMethodModifiers(JNIEnv *env, jclass cls, int cp_index,
       for (int i = 0; i < methods_count; i++) {
         Method* method = methods->at(i);
         if (method->name() == name && method->signature() == signature) {
-            return method->access_flags().as_int() & JVM_RECOGNIZED_METHOD_MODIFIERS;
+            return method->access_flags().as_method_flags();
         }
       }
       return -1;

src/hotspot/share/prims/jvmtiClassFileReconstituter.cpp

@@ -85,7 +85,7 @@ void JvmtiClassFileReconstituter::write_field_infos() {
     // JVMSpec|         attribute_info attributes[attributes_count];
     // JVMSpec|   }
 
-    write_u2(access_flags.as_int() & JVM_RECOGNIZED_FIELD_MODIFIERS);
+    write_u2(access_flags.as_field_flags());
     write_u2(name_index);
     write_u2(signature_index);
     u2 attr_count = 0;
@@ -704,7 +704,7 @@ void JvmtiClassFileReconstituter::write_method_info(const methodHandle& method)
     return;
   }
 
-  write_u2(access_flags.as_int() & JVM_RECOGNIZED_METHOD_MODIFIERS);
+  write_u2(access_flags.as_method_flags());
   write_u2(const_method->name_index());
   write_u2(const_method->signature_index());
 
@@ -919,7 +919,7 @@ void JvmtiClassFileReconstituter::write_class_file_format() {
   copy_cpool_bytes(writeable_address(cpool_size()));
 
   // JVMSpec|           u2 access_flags;
-  write_u2(ik()->access_flags().as_int() & JVM_RECOGNIZED_CLASS_MODIFIERS);
+  write_u2(ik()->access_flags().as_class_flags());
 
   // JVMSpec|           u2 this_class;
   // JVMSpec|           u2 super_class;

src/hotspot/share/prims/jvmtiEnv.cpp

@@ -3149,7 +3149,7 @@ jvmtiError
 JvmtiEnv::GetFieldModifiers(fieldDescriptor* fdesc_ptr, jint* modifiers_ptr) {
 
   AccessFlags resultFlags = fdesc_ptr->access_flags();
-  jint result = resultFlags.as_int();
+  jint result = resultFlags.as_unsigned_short();
   *modifiers_ptr = result;
 
   return JVMTI_ERROR_NONE;
@@ -3228,7 +3228,7 @@ JvmtiEnv::GetMethodDeclaringClass(Method* method, jclass* declaring_class_ptr) {
 jvmtiError
 JvmtiEnv::GetMethodModifiers(Method* method, jint* modifiers_ptr) {
   NULL_CHECK(method, JVMTI_ERROR_INVALID_METHODID);
-  (*modifiers_ptr) = method->access_flags().as_int() & JVM_RECOGNIZED_METHOD_MODIFIERS;
+  (*modifiers_ptr) = method->access_flags().as_method_flags();
   return JVMTI_ERROR_NONE;
 } /* end GetMethodModifiers */