8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #ifndef SHARE_GC_SHENANDOAH_SHENANDOAHSTRINGDEDUP_INLINE_HPP
26 #define SHARE_GC_SHENANDOAH_SHENANDOAHSTRINGDEDUP_INLINE_HPP
27
28 #include "gc/shenandoah/shenandoahStringDedup.hpp"
29
30 #include "classfile/javaClasses.inline.hpp"
31
32 bool ShenandoahStringDedup::is_string_candidate(oop obj) {
33 assert(Thread::current()->is_Worker_thread(),
34 "Only from a GC worker thread");
35 return java_lang_String::is_instance(obj) &&
36 java_lang_String::value(obj) != nullptr;
37 }
38
39 bool ShenandoahStringDedup::dedup_requested(oop obj) {
40 return java_lang_String::test_and_set_deduplication_requested(obj);
41 }
42
43 bool ShenandoahStringDedup::is_candidate(oop obj) {
44 if (!is_string_candidate(obj)) {
45 return false;
46 }
47
48 const markWord mark = obj->mark();
49
50 // Having/had displaced header, too risky to deal with them, skip
51 if (mark == markWord::INFLATING() || mark.has_displaced_mark_helper()) {
52 return false;
53 }
54
55 if (StringDedup::is_below_threshold_age(mark.age())) {
56 // Increase string age and enqueue it when it reaches age threshold
57 markWord new_mark = mark.incr_age();
58 if (mark == obj->cas_set_mark(new_mark, mark)) {
59 return StringDedup::is_threshold_age(new_mark.age()) &&
60 !dedup_requested(obj);
61 }
62 }
63 return false;
64 }
65
66 #endif // SHARE_GC_SHENANDOAH_SHENANDOAHSTRINGDEDUP_INLINE_HPP
|
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #ifndef SHARE_GC_SHENANDOAH_SHENANDOAHSTRINGDEDUP_INLINE_HPP
26 #define SHARE_GC_SHENANDOAH_SHENANDOAHSTRINGDEDUP_INLINE_HPP
27
28 #include "classfile/javaClasses.inline.hpp"
29 #include "gc/shenandoah/shenandoahHeap.inline.hpp"
30 #include "gc/shenandoah/shenandoahStringDedup.hpp"
31 #include "oops/markWord.hpp"
32
33 bool ShenandoahStringDedup::is_string_candidate(oop obj) {
34 assert(Thread::current()->is_Worker_thread(),
35 "Only from a GC worker thread");
36 return java_lang_String::is_instance(obj) &&
37 java_lang_String::value(obj) != nullptr;
38 }
39
40 bool ShenandoahStringDedup::dedup_requested(oop obj) {
41 return java_lang_String::test_and_set_deduplication_requested(obj);
42 }
43
44 bool ShenandoahStringDedup::is_candidate(oop obj) {
45 if (!is_string_candidate(obj)) {
46 return false;
47 }
48
49 uint age = ShenandoahHeap::get_object_age(obj);
50 return (age <= markWord::max_age) &&
51 StringDedup::is_below_threshold_age(age) &&
52 !dedup_requested(obj);
53 }
54
55 #endif // SHARE_GC_SHENANDOAH_SHENANDOAHSTRINGDEDUP_INLINE_HPP
|