Mercurial > hg > graal-compiler
view src/share/vm/runtime/fieldDescriptor.hpp @ 3917:eca1193ca245
4965777: GC changes to support use of discovered field for pending references
Summary: If and when the reference handler thread is able to use the discovered field to link reference objects in its pending list, so will GC. In that case, GC will scan through this field once a reference object has been placed on the pending list, but not scan that field before that stage, as the field is used by the concurrent GC thread to link discovered objects. When ReferenceHandleR thread does not use the discovered field for the purpose of linking the elements in the pending list, as would be the case in older JDKs, the JVM will fall back to the old behaviour of using the next field for that purpose.
Reviewed-by: jcoomes, mchung, stefank
author | ysr |
---|---|
date | Wed, 07 Sep 2011 13:55:42 -0700 |
parents | 1d1603768966 |
children | ff6a991c6e3c e6b1331a51d2 |
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/* * Copyright (c) 1997, 2011, 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 * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. * */ #ifndef SHARE_VM_RUNTIME_FIELDDESCRIPTOR_HPP #define SHARE_VM_RUNTIME_FIELDDESCRIPTOR_HPP #include "oops/constantPoolOop.hpp" #include "oops/klassOop.hpp" #include "oops/oop.inline.hpp" #include "oops/symbol.hpp" #include "runtime/fieldType.hpp" #include "utilities/accessFlags.hpp" #include "utilities/constantTag.hpp" // A fieldDescriptor describes the attributes of a single field (instance or class variable). // It needs the class constant pool to work (because it only holds indices into the pool // rather than the actual info). class fieldDescriptor VALUE_OBJ_CLASS_SPEC { private: AccessFlags _access_flags; int _name_index; int _signature_index; int _initial_value_index; int _offset; int _generic_signature_index; int _index; // index into fields() array constantPoolHandle _cp; public: Symbol* name() const { return _cp->symbol_at(_name_index); } Symbol* signature() const { return _cp->symbol_at(_signature_index); } klassOop field_holder() const { return _cp->pool_holder(); } constantPoolOop constants() const { return _cp(); } AccessFlags access_flags() const { return _access_flags; } oop loader() const; // Offset (in words) of field from start of instanceOop / klassOop int offset() const { return _offset; } Symbol* generic_signature() const { return (_generic_signature_index > 0 ? _cp->symbol_at(_generic_signature_index) : (Symbol*)NULL); } int index() const { return _index; } typeArrayOop annotations() const; // Initial field value bool has_initial_value() const { return _initial_value_index != 0; } constantTag initial_value_tag() const; // The tag will return true on one of is_int(), is_long(), is_single(), is_double() jint int_initial_value() const; jlong long_initial_value() const; jfloat float_initial_value() const; jdouble double_initial_value() const; oop string_initial_value(TRAPS) const; // Field signature type BasicType field_type() const { return FieldType::basic_type(signature()); } // Access flags bool is_public() const { return _access_flags.is_public(); } bool is_private() const { return _access_flags.is_private(); } bool is_protected() const { return _access_flags.is_protected(); } bool is_package_private() const { return !is_public() && !is_private() && !is_protected(); } bool is_static() const { return _access_flags.is_static(); } bool is_final() const { return _access_flags.is_final(); } bool is_volatile() const { return _access_flags.is_volatile(); } bool is_transient() const { return _access_flags.is_transient(); } bool is_synthetic() const { return _access_flags.is_synthetic(); } bool is_field_access_watched() const { return _access_flags.is_field_access_watched(); } bool is_field_modification_watched() const { return _access_flags.is_field_modification_watched(); } void set_is_field_access_watched(const bool value) { _access_flags.set_is_field_access_watched(value); } void set_is_field_modification_watched(const bool value) { _access_flags.set_is_field_modification_watched(value); } // Initialization void initialize(klassOop k, int index); // Print void print_on(outputStream* st) const PRODUCT_RETURN; void print_on_for(outputStream* st, oop obj) PRODUCT_RETURN; }; #endif // SHARE_VM_RUNTIME_FIELDDESCRIPTOR_HPP