--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/src/hotspot/share/oops/fieldStreams.hpp Tue Sep 12 19:03:39 2017 +0200
@@ -0,0 +1,249 @@
+/*
+ * Copyright (c) 2011, 2017, 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_OOPS_FIELDSTREAMS_HPP
+#define SHARE_VM_OOPS_FIELDSTREAMS_HPP
+
+#include "oops/instanceKlass.hpp"
+#include "oops/fieldInfo.hpp"
+#include "runtime/fieldDescriptor.hpp"
+
+// The is the base class for iteration over the fields array
+// describing the declared fields in the class. Several subclasses
+// are provided depending on the kind of iteration required. The
+// JavaFieldStream is for iterating over regular Java fields and it
+// generally the preferred iterator. InternalFieldStream only
+// iterates over fields that have been injected by the JVM.
+// AllFieldStream exposes all fields and should only be used in rare
+// cases.
+class FieldStreamBase : public StackObj {
+ protected:
+ Array<u2>* _fields;
+ constantPoolHandle _constants;
+ int _index;
+ int _limit;
+ int _generic_signature_slot;
+ fieldDescriptor _fd_buf;
+
+ FieldInfo* field() const { return FieldInfo::from_field_array(_fields, _index); }
+ InstanceKlass* field_holder() const { return _constants->pool_holder(); }
+
+ int init_generic_signature_start_slot() {
+ int length = _fields->length();
+ int num_fields = _index;
+ int skipped_generic_signature_slots = 0;
+ FieldInfo* fi;
+ AccessFlags flags;
+ /* Scan from 0 to the current _index. Count the number of generic
+ signature slots for field[0] to field[_index - 1]. */
+ for (int i = 0; i < _index; i++) {
+ fi = FieldInfo::from_field_array(_fields, i);
+ flags.set_flags(fi->access_flags());
+ if (flags.field_has_generic_signature()) {
+ length --;
+ skipped_generic_signature_slots ++;
+ }
+ }
+ /* Scan from the current _index. */
+ for (int i = _index; i*FieldInfo::field_slots < length; i++) {
+ fi = FieldInfo::from_field_array(_fields, i);
+ flags.set_flags(fi->access_flags());
+ if (flags.field_has_generic_signature()) {
+ length --;
+ }
+ num_fields ++;
+ }
+ _generic_signature_slot = length + skipped_generic_signature_slots;
+ assert(_generic_signature_slot <= _fields->length(), "");
+ return num_fields;
+ }
+
+ FieldStreamBase(Array<u2>* fields, const constantPoolHandle& constants, int start, int limit) {
+ _fields = fields;
+ _constants = constants;
+ _index = start;
+ int num_fields = init_generic_signature_start_slot();
+ if (limit < start) {
+ _limit = num_fields;
+ } else {
+ _limit = limit;
+ }
+ }
+
+ FieldStreamBase(Array<u2>* fields, const constantPoolHandle& constants) {
+ _fields = fields;
+ _constants = constants;
+ _index = 0;
+ _limit = init_generic_signature_start_slot();
+ }
+
+ public:
+ FieldStreamBase(InstanceKlass* klass) {
+ _fields = klass->fields();
+ _constants = klass->constants();
+ _index = 0;
+ _limit = klass->java_fields_count();
+ init_generic_signature_start_slot();
+ assert(klass == field_holder(), "");
+ }
+
+ // accessors
+ int index() const { return _index; }
+
+ void next() {
+ if (access_flags().field_has_generic_signature()) {
+ _generic_signature_slot ++;
+ assert(_generic_signature_slot <= _fields->length(), "");
+ }
+ _index += 1;
+ }
+ bool done() const { return _index >= _limit; }
+
+ // Accessors for current field
+ AccessFlags access_flags() const {
+ AccessFlags flags;
+ flags.set_flags(field()->access_flags());
+ return flags;
+ }
+
+ void set_access_flags(u2 flags) const {
+ field()->set_access_flags(flags);
+ }
+
+ void set_access_flags(AccessFlags flags) const {
+ set_access_flags(flags.as_short());
+ }
+
+ Symbol* name() const {
+ return field()->name(_constants);
+ }
+
+ Symbol* signature() const {
+ return field()->signature(_constants);
+ }
+
+ Symbol* generic_signature() const {
+ if (access_flags().field_has_generic_signature()) {
+ assert(_generic_signature_slot < _fields->length(), "out of bounds");
+ int index = _fields->at(_generic_signature_slot);
+ return _constants->symbol_at(index);
+ } else {
+ return NULL;
+ }
+ }
+
+ int offset() const {
+ return field()->offset();
+ }
+
+ int allocation_type() const {
+ return field()->allocation_type();
+ }
+
+ void set_offset(int offset) {
+ field()->set_offset(offset);
+ }
+
+ bool is_offset_set() const {
+ return field()->is_offset_set();
+ }
+
+ bool is_contended() const {
+ return field()->is_contended();
+ }
+
+ int contended_group() const {
+ return field()->contended_group();
+ }
+
+ // bridge to a heavier API:
+ fieldDescriptor& field_descriptor() const {
+ fieldDescriptor& field = const_cast<fieldDescriptor&>(_fd_buf);
+ field.reinitialize(field_holder(), _index);
+ return field;
+ }
+};
+
+// Iterate over only the internal fields
+class JavaFieldStream : public FieldStreamBase {
+ public:
+ JavaFieldStream(const InstanceKlass* k): FieldStreamBase(k->fields(), k->constants(), 0, k->java_fields_count()) {}
+
+ int name_index() const {
+ assert(!field()->is_internal(), "regular only");
+ return field()->name_index();
+ }
+ void set_name_index(int index) {
+ assert(!field()->is_internal(), "regular only");
+ field()->set_name_index(index);
+ }
+ int signature_index() const {
+ assert(!field()->is_internal(), "regular only");
+ return field()->signature_index();
+ }
+ void set_signature_index(int index) {
+ assert(!field()->is_internal(), "regular only");
+ field()->set_signature_index(index);
+ }
+ int generic_signature_index() const {
+ assert(!field()->is_internal(), "regular only");
+ if (access_flags().field_has_generic_signature()) {
+ assert(_generic_signature_slot < _fields->length(), "out of bounds");
+ return _fields->at(_generic_signature_slot);
+ } else {
+ return 0;
+ }
+ }
+ void set_generic_signature_index(int index) {
+ assert(!field()->is_internal(), "regular only");
+ if (access_flags().field_has_generic_signature()) {
+ assert(_generic_signature_slot < _fields->length(), "out of bounds");
+ _fields->at_put(_generic_signature_slot, index);
+ }
+ }
+ int initval_index() const {
+ assert(!field()->is_internal(), "regular only");
+ return field()->initval_index();
+ }
+ void set_initval_index(int index) {
+ assert(!field()->is_internal(), "regular only");
+ return field()->set_initval_index(index);
+ }
+};
+
+
+// Iterate over only the internal fields
+class InternalFieldStream : public FieldStreamBase {
+ public:
+ InternalFieldStream(InstanceKlass* k): FieldStreamBase(k->fields(), k->constants(), k->java_fields_count(), 0) {}
+};
+
+
+class AllFieldStream : public FieldStreamBase {
+ public:
+ AllFieldStream(Array<u2>* fields, const constantPoolHandle& constants): FieldStreamBase(fields, constants) {}
+ AllFieldStream(InstanceKlass* k): FieldStreamBase(k->fields(), k->constants()) {}
+};
+
+#endif // SHARE_VM_OOPS_FIELDSTREAMS_HPP