1126
1127 /**
1128 * Ensures that loads and stores before the fence will not be reordered
1129 * with loads and stores after the fence. Implies the effects of both
1130 * loadFence() and storeFence(), and in addition, the effect of a StoreLoad
1131 * barrier.
1132 *
1133 * Corresponds to C11 atomic_thread_fence(memory_order_seq_cst).
1134 * @since 1.8
1135 */
1136 public native void fullFence();
1137
1138 /**
1139 * Throws IllegalAccessError; for use by the VM.
1140 * @since 1.8
1141 */
1142 private static void throwIllegalAccessError() {
1143 throw new IllegalAccessError();
1144 }
1145
1146 }
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1126
1127 /**
1128 * Ensures that loads and stores before the fence will not be reordered
1129 * with loads and stores after the fence. Implies the effects of both
1130 * loadFence() and storeFence(), and in addition, the effect of a StoreLoad
1131 * barrier.
1132 *
1133 * Corresponds to C11 atomic_thread_fence(memory_order_seq_cst).
1134 * @since 1.8
1135 */
1136 public native void fullFence();
1137
1138 /**
1139 * Throws IllegalAccessError; for use by the VM.
1140 * @since 1.8
1141 */
1142 private static void throwIllegalAccessError() {
1143 throw new IllegalAccessError();
1144 }
1145
1146 public final static boolean LITTLE_ENDIAN = false;
1147 public final static boolean BIG_ENDIAN = true;
1148
1149 public native boolean getByteOrder();
1150
1151 public native boolean unalignedAccess();
1152
1153 public long getLongUnaligned(Object o, long offset) {
1154 if ((offset & 7) == 0) {
1155 return getLong(o, offset);
1156 } else if ((offset & 3) == 0) {
1157 return mem.makeLong(getInt(o, offset),
1158 getInt(o, offset + 4));
1159 } else if ((offset & 1) == 0) {
1160 return mem.makeLong(getShort(o, offset),
1161 getShort(o, offset + 2),
1162 getShort(o, offset + 4),
1163 getShort(o, offset + 6));
1164 } else {
1165 return mem.makeLong(getByte(o, offset),
1166 getByte(o, offset + 1),
1167 getByte(o, offset + 2),
1168 getByte(o, offset + 3),
1169 getByte(o, offset + 4),
1170 getByte(o, offset + 5),
1171 getByte(o, offset + 6),
1172 getByte(o, offset + 7));
1173 }
1174 }
1175 public long getLongUnaligned(Object o, long offset, boolean bigEndian) {
1176 return mem.fromEndian(bigEndian, getLongUnaligned(o, offset));
1177 }
1178
1179 public int getIntUnaligned(Object o, long offset) {
1180 if ((offset & 3) == 0) {
1181 return getInt(o, offset);
1182 } else if ((offset & 1) == 0) {
1183 return mem.makeInt(getShort(o, offset),
1184 getShort(o, offset + 2));
1185 } else {
1186 return mem.makeInt(getByte(o, offset),
1187 getByte(o, offset + 1),
1188 getByte(o, offset + 2),
1189 getByte(o, offset + 3));
1190 }
1191 }
1192 public int getIntUnaligned(Object o, long offset, boolean bigEndian) {
1193 return mem.fromEndian(bigEndian, getIntUnaligned(o, offset));
1194 }
1195
1196 public short getShortUnaligned(Object o, long offset) {
1197 if ((offset & 1) == 0) {
1198 return getShort(o, offset);
1199 } else {
1200 return mem.makeShort(getByte(o, offset),
1201 getByte(o, offset + 1));
1202 }
1203 }
1204 public short getShortUnaligned(Object o, long offset, boolean bigEndian) {
1205 return mem.fromEndian(bigEndian, getShortUnaligned(o, offset));
1206 }
1207
1208 public char getCharUnaligned(Object o, long offset) {
1209 return (char)getShortUnaligned(o, offset);
1210 }
1211 public char getCharUnaligned(Object o, long offset, boolean bigEndian) {
1212 return mem.fromEndian(bigEndian, getCharUnaligned(o, offset));
1213 }
1214
1215 public void putLongUnaligned(Object o, long offset, long x) {
1216 if ((offset & 7) == 0) {
1217 putLong(o, offset, x);
1218 } else if ((offset & 3) == 0) {
1219 mem.putLongParts(this, o, offset,
1220 (int)(x >> 0),
1221 (int)(x >>> 32));
1222 } else if ((offset & 1) == 0) {
1223 mem.putLongParts(this, o, offset,
1224 (short)(x >>> 0),
1225 (short)(x >>> 16),
1226 (short)(x >>> 32),
1227 (short)(x >>> 48));
1228 } else {
1229 mem.putLongParts(this, o, offset,
1230 (byte)(x >>> 0),
1231 (byte)(x >>> 8),
1232 (byte)(x >>> 16),
1233 (byte)(x >>> 24),
1234 (byte)(x >>> 32),
1235 (byte)(x >>> 40),
1236 (byte)(x >>> 48),
1237 (byte)(x >>> 56));
1238 }
1239 }
1240
1241 public void putIntUnaligned(Object o, long offset, int x) {
1242 if ((offset & 3) == 0) {
1243 putInt(o, offset, x);
1244 } else if ((offset & 1) == 0) {
1245 mem.putIntParts(this, o, offset,
1246 (short)(x >> 0),
1247 (short)(x >>> 16));
1248 } else {
1249 mem.putIntParts(this, o, offset,
1250 (byte)(x >>> 0),
1251 (byte)(x >>> 8),
1252 (byte)(x >>> 16),
1253 (byte)(x >>> 24));
1254 }
1255 }
1256
1257 public void putShortUnaligned(Object o, long offset, short x) {
1258 if ((offset & 1) == 0) {
1259 putShort(o, offset, x);
1260 } else {
1261 mem.putShortParts(this, o, offset,
1262 (byte)(x >>> 0),
1263 (byte)(x >>> 8));
1264 }
1265 }
1266
1267 public void putCharUnaligned(Object o, long offset, char x) {
1268 putShortUnaligned(o, offset, (short)x);
1269 }
1270
1271 private static final boolean byteOrder = theUnsafe.getByteOrder();
1272
1273 private static final NativeAccess mem
1274 = (byteOrder == LITTLE_ENDIAN) ? new NativeLittleEndian() : new NativeBigEndian();
1275
1276 private abstract static class NativeAccess {
1277 // Native-enianness-dependent scatter/gather methods for integer types
1278 abstract long makeLong(int i0, int i1);
1279 abstract long makeLong(short i0, short i1, short i2, short i3);
1280 abstract long makeLong(byte i0, byte i1, byte i2, byte i3, byte i4, byte i5, byte i6, byte i7);
1281 abstract int makeInt(short i0, short i1);
1282 abstract int makeInt(byte i0, byte i1, byte i2, byte i3);
1283 abstract short makeShort(byte i0, byte i1);
1284
1285 abstract void putLongParts(Unsafe theUnsafe, Object o, long offset, int i0, int i1);
1286 abstract void putLongParts(Unsafe theUnsafe, Object o, long offset,
1287 short i0, short i1, short i2, short i3);
1288 abstract void putLongParts(Unsafe theUnsafe, Object o, long offset,
1289 byte i0, byte i1, byte i2, byte i3, byte i4,
1290 byte i5, byte i6, byte i7);
1291 abstract void putIntParts(Unsafe theUnsafe, Object o, long offset, short i0, short i1);
1292 abstract void putIntParts(Unsafe theUnsafe, Object o, long offset,
1293 byte i0, byte i1, byte i2, byte i3);
1294 abstract void putShortParts(Unsafe theUnsafe, Object o, long offset, byte i0, byte i1);
1295
1296 // Byte-reverse an integer if necessary
1297 abstract char fromEndian(boolean big, char n);
1298 abstract short fromEndian(boolean big, short n);
1299 abstract int fromEndian(boolean big, int n);
1300 abstract long fromEndian(boolean big, long n);
1301
1302 // Zero-extend an integer type
1303 final int toUnsignedInt(byte n) { return n & 0xff; }
1304 final int toUnsignedInt(short n) { return n & 0xffff; }
1305 final long toUnsignedLong(byte n) { return n & 0xffl; }
1306 final long toUnsignedLong(short n) { return n & 0xffffl; }
1307 final long toUnsignedLong(int n) { return n & 0xffffffffl; }
1308 }
1309
1310 private static class NativeLittleEndian extends NativeAccess {
1311 long makeLong(byte i0, byte i1, byte i2, byte i3, byte i4, byte i5, byte i6, byte i7) {
1312 return ((toUnsignedLong(i0) << 0)
1313 | (toUnsignedLong(i1) << 8)
1314 | (toUnsignedLong(i2) << 16)
1315 | (toUnsignedLong(i3) << 24)
1316 | (toUnsignedLong(i4) << 32)
1317 | (toUnsignedLong(i5) << 40)
1318 | (toUnsignedLong(i6) << 48)
1319 | (toUnsignedLong(i7) << 56));
1320 }
1321 long makeLong(short i0, short i1, short i2, short i3) {
1322 return ((toUnsignedLong(i0) << 0)
1323 | (toUnsignedLong(i1) << 16)
1324 | (toUnsignedLong(i2) << 32)
1325 | (toUnsignedLong(i3) << 48));
1326 }
1327 long makeLong(int i0, int i1) {
1328 return (toUnsignedLong(i0) << 0)
1329 | (toUnsignedLong(i1) << 32);
1330 }
1331 int makeInt(short i0, short i1) {
1332 return (toUnsignedInt(i0) << 0)
1333 | (toUnsignedInt(i1) << 16);
1334 }
1335 int makeInt(byte i0, byte i1, byte i2, byte i3) {
1336 return ((toUnsignedInt(i0) << 0)
1337 | (toUnsignedInt(i1) << 8)
1338 | (toUnsignedInt(i2) << 16)
1339 | (toUnsignedInt(i3) << 24));
1340 }
1341 short makeShort(byte i0, byte i1) {
1342 return (short)((toUnsignedInt(i0) << 0)
1343 | (toUnsignedInt(i1) << 8));
1344 }
1345 void putLongParts(Unsafe theUnsafe, Object o, long offset, byte i0, byte i1, byte i2, byte i3, byte i4, byte i5, byte i6, byte i7) {
1346 theUnsafe.putByte(o, offset + 0, i0);
1347 theUnsafe.putByte(o, offset + 1, i1);
1348 theUnsafe.putByte(o, offset + 2, i2);
1349 theUnsafe.putByte(o, offset + 3, i3);
1350 theUnsafe.putByte(o, offset + 4, i4);
1351 theUnsafe.putByte(o, offset + 5, i5);
1352 theUnsafe.putByte(o, offset + 6, i6);
1353 theUnsafe.putByte(o, offset + 7, i7);
1354 }
1355 void putLongParts(Unsafe theUnsafe, Object o, long offset, short i0, short i1, short i2, short i3) {
1356 theUnsafe.putShort(o, offset + 0, i0);
1357 theUnsafe.putShort(o, offset + 2, i1);
1358 theUnsafe.putShort(o, offset + 4, i2);
1359 theUnsafe.putShort(o, offset + 6, i3);
1360 }
1361 void putLongParts(Unsafe theUnsafe, Object o, long offset, int i0, int i1) {
1362 theUnsafe.putInt(o, offset + 0, i0);
1363 theUnsafe.putInt(o, offset + 4, i1);
1364 }
1365 void putIntParts(Unsafe theUnsafe, Object o, long offset, short i0, short i1) {
1366 theUnsafe.putShort(o, offset + 0, i0);
1367 theUnsafe.putShort(o, offset + 2, i1);
1368 }
1369 void putIntParts(Unsafe theUnsafe, Object o, long offset, byte i0, byte i1, byte i2, byte i3) {
1370 theUnsafe.putByte(o, offset + 0, i0);
1371 theUnsafe.putByte(o, offset + 1, i1);
1372 theUnsafe.putByte(o, offset + 2, i2);
1373 theUnsafe.putByte(o, offset + 3, i3);
1374 }
1375 void putShortParts(Unsafe theUnsafe, Object o, long offset, byte i0, byte i1) {
1376 theUnsafe.putByte(o, offset + 0, i0);
1377 theUnsafe.putByte(o, offset + 1, i1);
1378 }
1379 char fromEndian(boolean big, char n) { return big ? Character.reverseBytes(n) : n; }
1380 short fromEndian(boolean big, short n) { return big ? Short.reverseBytes(n) : n; }
1381 int fromEndian(boolean big, int n) { return big ? Integer.reverseBytes(n) : n; }
1382 long fromEndian(boolean big, long n) { return big ? Long.reverseBytes(n) : n; }
1383 }
1384
1385 private static class NativeBigEndian extends NativeAccess {
1386 long makeLong(byte i0, byte i1, byte i2, byte i3, byte i4, byte i5, byte i6, byte i7) {
1387 return ((toUnsignedLong(i0) << 56)
1388 | (toUnsignedLong(i1) << 48)
1389 | (toUnsignedLong(i2) << 40)
1390 | (toUnsignedLong(i3) << 32)
1391 | (toUnsignedLong(i4) << 24)
1392 | (toUnsignedLong(i5) << 16)
1393 | (toUnsignedLong(i6) << 8)
1394 | (toUnsignedLong(i7) << 0));
1395 }
1396 long makeLong(short i0, short i1, short i2, short i3) {
1397 return ((toUnsignedLong(i0) << 48)
1398 | (toUnsignedLong(i1) << 32)
1399 | (toUnsignedLong(i2) << 16)
1400 | (toUnsignedLong(i3) << 0));
1401 }
1402 long makeLong(int i0, int i1) {
1403 return (toUnsignedLong(i0) << 32)
1404 | (toUnsignedLong(i1) << 0);
1405 }
1406 int makeInt(byte i0, byte i1, byte i2, byte i3) {
1407 return ((toUnsignedInt(i0) << 24)
1408 | (toUnsignedInt(i1) << 16)
1409 | (toUnsignedInt(i2) << 8)
1410 | (toUnsignedInt(i3) << 0));
1411 }
1412 int makeInt(short i0, short i1) {
1413 return ((toUnsignedInt(i0) << 16)
1414 | (toUnsignedInt(i1) << 0));
1415 }
1416 short makeShort(byte i0, byte i1) {
1417 return (short)((toUnsignedInt(i0) << 8)
1418 | (toUnsignedInt(i1) << 0));
1419 }
1420 void putLongParts(Unsafe theUnsafe, Object o, long offset, byte i0, byte i1, byte i2, byte i3, byte i4, byte i5, byte i6, byte i7) {
1421 theUnsafe.putByte(o, offset + 0, i7);
1422 theUnsafe.putByte(o, offset + 1, i6);
1423 theUnsafe.putByte(o, offset + 2, i5);
1424 theUnsafe.putByte(o, offset + 3, i4);
1425 theUnsafe.putByte(o, offset + 4, i3);
1426 theUnsafe.putByte(o, offset + 5, i2);
1427 theUnsafe.putByte(o, offset + 6, i1);
1428 theUnsafe.putByte(o, offset + 7, i0);
1429 }
1430 void putLongParts(Unsafe theUnsafe, Object o, long offset, short i0, short i1, short i2, short i3) {
1431 theUnsafe.putShort(o, offset + 0, i3);
1432 theUnsafe.putShort(o, offset + 2, i2);
1433 theUnsafe.putShort(o, offset + 4, i1);
1434 theUnsafe.putShort(o, offset + 6, i0);
1435 }
1436 void putLongParts(Unsafe theUnsafe, Object o, long offset, int i0, int i1) {
1437 theUnsafe.putInt(o, offset + 0, i1);
1438 theUnsafe.putInt(o, offset + 4, i0);
1439 }
1440 void putIntParts(Unsafe theUnsafe, Object o, long offset, byte i0, byte i1, byte i2, byte i3) {
1441 theUnsafe.putByte(o, offset + 0, i3);
1442 theUnsafe.putByte(o, offset + 1, i2);
1443 theUnsafe.putByte(o, offset + 2, i1);
1444 theUnsafe.putByte(o, offset + 3, i0);
1445 }
1446 void putIntParts(Unsafe theUnsafe, Object o, long offset, short i0, short i1) {
1447 theUnsafe.putShort(o, offset + 0, i1);
1448 theUnsafe.putShort(o, offset + 2, i0);
1449 }
1450 void putShortParts(Unsafe theUnsafe, Object o, long offset, byte i0, byte i1) {
1451 theUnsafe.putByte(o, offset + 0, i1);
1452 theUnsafe.putByte(o, offset + 1, i0);
1453 }
1454 char fromEndian(boolean big, char n) { return big ? n : Character.reverseBytes(n); }
1455 short fromEndian(boolean big, short n) { return big ? n : Short.reverseBytes(n); }
1456 int fromEndian(boolean big, int n) { return big ? n : Integer.reverseBytes(n); }
1457 long fromEndian(boolean big, long n) { return big ? n : Long.reverseBytes(n); }
1458 }
1459 }
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