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.
20  *
21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22  * or visit www.oracle.com if you need additional information or have any
23  * questions.
24  */
25 
26 package jdk.internal.foreign;
27 
28 import java.lang.foreign.MemorySegment;
29 import java.lang.foreign.SegmentAllocator;
30 
31 public final class SlicingAllocator implements SegmentAllocator {
32 
33     private final MemorySegment segment;
34     private final long maxAlign;
35 
36     private long sp = 0L;
37 
38     public SlicingAllocator(MemorySegment segment) {
39         this.segment = segment;
40         this.maxAlign = ((AbstractMemorySegmentImpl)segment).maxAlignMask();
41     }
42 
43     MemorySegment trySlice(long byteSize, long byteAlignment) {
44         long min = segment.address();
45         long start = Utils.alignUp(min + sp, byteAlignment) - min;
46         MemorySegment slice = segment.asSlice(start, byteSize, byteAlignment);
47         sp = start + byteSize;
48         return slice;
49     }
50 
51     @Override
52     public MemorySegment allocate(long byteSize, long byteAlignment) {
53         Utils.checkAllocationSizeAndAlign(byteSize, byteAlignment);
54         // try to slice from current segment first...
55         return trySlice(byteSize, byteAlignment);
56     }
57 }

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.
20  *
21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22  * or visit www.oracle.com if you need additional information or have any
23  * questions.
24  */
25 
26 package jdk.internal.foreign;
27 
28 import java.lang.foreign.MemorySegment;
29 import java.lang.foreign.SegmentAllocator;
30 
31 public final class SlicingAllocator implements SegmentAllocator {
32 
33     private final MemorySegment segment;

34 
35     private long sp = 0L;
36 
37     public SlicingAllocator(MemorySegment segment) {
38         this.segment = segment;

39     }
40 
41     MemorySegment trySlice(long byteSize, long byteAlignment) {
42         long min = segment.address();
43         long start = Utils.alignUp(min + sp, byteAlignment) - min;
44         MemorySegment slice = segment.asSlice(start, byteSize, byteAlignment);
45         sp = start + byteSize;
46         return slice;
47     }
48 
49     @Override
50     public MemorySegment allocate(long byteSize, long byteAlignment) {
51         Utils.checkAllocationSizeAndAlign(byteSize, byteAlignment);
52         // try to slice from current segment first...
53         return trySlice(byteSize, byteAlignment);
54     }
55 }