1 /*
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3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4  *
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7  * published by the Free Software Foundation.  Oracle designates this
8  * particular file as subject to the "Classpath" exception as provided
9  * by Oracle in the LICENSE file that accompanied this code.
10  *
11  * This code is distributed in the hope that it will be useful, but WITHOUT
12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
14  * version 2 for more details (a copy is included in the LICENSE file that
15  * accompanied this code).
16  *
17  * You should have received a copy of the GNU General Public License version
18  * 2 along with this work; if not, write to the Free Software Foundation,
19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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24  */
25 
26 package sun.java2d.marlin;
27 
28 import static sun.java2d.marlin.MarlinConst.LOG_UNSAFE_MALLOC;
29 import jdk.internal.misc.Unsafe;
30 import jdk.internal.ref.CleanerFactory;
31 
32 /**
33  *
34  */
35 final class OffHeapArray  {
36 
37     // unsafe reference
38     static final Unsafe UNSAFE;
39     // size of int / float
40     static final int SIZE_INT;
41 
42     static {
43         UNSAFE   = Unsafe.getUnsafe();
44         SIZE_INT = Unsafe.ARRAY_INT_INDEX_SCALE;
45     }
46 
47     /* members */
48     long address;
49     long length;
50     int  used;
51 
OffHeapArray(final Object parent, final long len)52     OffHeapArray(final Object parent, final long len) {
53         // note: may throw OOME:
54         this.address = UNSAFE.allocateMemory(len);
55         this.length  = len;
56         this.used    = 0;
57         if (LOG_UNSAFE_MALLOC) {
58             MarlinUtils.logInfo(System.currentTimeMillis()
59                                 + ": OffHeapArray.allocateMemory =   "
60                                 + len + " to addr = " + this.address);
61         }
62 
63         // Register a cleaning function to ensure freeing off-heap memory:
64         CleanerFactory.cleaner().register(parent, () -> this.free());
65     }
66 
67     /*
68      * As realloc may change the address, updating address is MANDATORY
69      * @param len new array length
70      * @throws OutOfMemoryError if the allocation is refused by the system
71      */
resize(final long len)72     void resize(final long len) {
73         // note: may throw OOME:
74         this.address = UNSAFE.reallocateMemory(address, len);
75         this.length  = len;
76         if (LOG_UNSAFE_MALLOC) {
77             MarlinUtils.logInfo(System.currentTimeMillis()
78                                 + ": OffHeapArray.reallocateMemory = "
79                                 + len + " to addr = " + this.address);
80         }
81     }
82 
free()83     void free() {
84         UNSAFE.freeMemory(this.address);
85         if (LOG_UNSAFE_MALLOC) {
86             MarlinUtils.logInfo(System.currentTimeMillis()
87                                 + ": OffHeapArray.freeMemory =       "
88                                 + this.length
89                                 + " at addr = " + this.address);
90         }
91         this.address = 0L;
92     }
93 
fill(final byte val)94     void fill(final byte val) {
95         UNSAFE.setMemory(this.address, this.length, val);
96     }
97 }
98