--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/hotspot/src/share/vm/oops/markOop.inline.hpp Sat Dec 01 00:00:00 2007 +0000
@@ -0,0 +1,80 @@
+/*
+ * Copyright 2006 Sun Microsystems, Inc. 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ *
+ */
+
+// Should this header be preserved during GC?
+inline bool markOopDesc::must_be_preserved_with_bias(oop obj_containing_mark) const {
+ assert(UseBiasedLocking, "unexpected");
+ if (has_bias_pattern()) {
+ // Will reset bias at end of collection
+ // Mark words of biased and currently locked objects are preserved separately
+ return false;
+ }
+ markOop prototype_header = prototype_for_object(obj_containing_mark);
+ if (prototype_header->has_bias_pattern()) {
+ // Individual instance which has its bias revoked; must return
+ // true for correctness
+ return true;
+ }
+ return (!is_unlocked() || !has_no_hash());
+}
+
+// Should this header (including its age bits) be preserved in the
+// case of a promotion failure during scavenge?
+inline bool markOopDesc::must_be_preserved_with_bias_for_promotion_failure(oop obj_containing_mark) const {
+ assert(UseBiasedLocking, "unexpected");
+ // We don't explicitly save off the mark words of biased and
+ // currently-locked objects during scavenges, so if during a
+ // promotion failure we encounter either a biased mark word or a
+ // klass which still has a biasable prototype header, we have to
+ // preserve the mark word. This results in oversaving, but promotion
+ // failures are rare, and this avoids adding more complex logic to
+ // the scavengers to call new variants of
+ // BiasedLocking::preserve_marks() / restore_marks() in the middle
+ // of a scavenge when a promotion failure has first been detected.
+ if (has_bias_pattern() ||
+ prototype_for_object(obj_containing_mark)->has_bias_pattern()) {
+ return true;
+ }
+ return (this != prototype());
+}
+
+// Should this header (including its age bits) be preserved in the
+// case of a scavenge in which CMS is the old generation?
+inline bool markOopDesc::must_be_preserved_with_bias_for_cms_scavenge(klassOop klass_of_obj_containing_mark) const {
+ assert(UseBiasedLocking, "unexpected");
+ // CMS scavenges preserve mark words in similar fashion to promotion failures; see above
+ if (has_bias_pattern() ||
+ klass_of_obj_containing_mark->klass_part()->prototype_header()->has_bias_pattern()) {
+ return true;
+ }
+ return (this != prototype());
+}
+
+inline markOop markOopDesc::prototype_for_object(oop obj) {
+#ifdef ASSERT
+ markOop prototype_header = obj->klass()->klass_part()->prototype_header();
+ assert(prototype_header == prototype() || prototype_header->has_bias_pattern(), "corrupt prototype header");
+#endif
+ return obj->klass()->klass_part()->prototype_header();
+}