1 /*
2 * Copyright (c) 2000, 2018, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
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.
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.misc;
27
28 import jdk.internal.HotSpotIntrinsicCandidate;
29 import jdk.internal.ref.Cleaner;
30 import jdk.internal.vm.annotation.ForceInline;
31 import sun.nio.ch.DirectBuffer;
32
33 import java.lang.reflect.Field;
34 import java.security.ProtectionDomain;
35
36
37 /**
38 * A collection of methods for performing low-level, unsafe operations.
39 * Although the class and all methods are public, use of this class is
40 * limited because only trusted code can obtain instances of it.
41 *
42 * <em>Note:</em> It is the resposibility of the caller to make sure
43 * arguments are checked before methods of this class are
44 * called. While some rudimentary checks are performed on the input,
45 * the checks are best effort and when performance is an overriding
46 * priority, as when methods of this class are optimized by the
47 * runtime compiler, some or all checks (if any) may be elided. Hence,
48 * the caller must not rely on the checks and corresponding
49 * exceptions!
50 *
51 * @author John R. Rose
52 * @see #getUnsafe
53 */
54
55 public final class Unsafe {
56
57 private static native void registerNatives();
58 static {
59 registerNatives();
60 }
61
62 private Unsafe() {}
63
64 private static final Unsafe theUnsafe = new Unsafe();
65
66 /**
67 * Provides the caller with the capability of performing unsafe
68 * operations.
69 *
70 * <p>The returned {@code Unsafe} object should be carefully guarded
71 * by the caller, since it can be used to read and write data at arbitrary
72 * memory addresses. It must never be passed to untrusted code.
73 *
74 * <p>Most methods in this class are very low-level, and correspond to a
75 * small number of hardware instructions (on typical machines). Compilers
76 * are encouraged to optimize these methods accordingly.
77 *
78 * <p>Here is a suggested idiom for using unsafe operations:
79 *
80 * <pre> {@code
81 * class MyTrustedClass {
82 * private static final Unsafe unsafe = Unsafe.getUnsafe();
83 * ...
84 * private long myCountAddress = ...;
85 * public int getCount() { return unsafe.getByte(myCountAddress); }
86 * }}</pre>
87 *
88 * (It may assist compilers to make the local variable {@code final}.)
89 */
90 public static Unsafe getUnsafe() {
91 return theUnsafe;
92 }
93
94 /// peek and poke operations
95 /// (compilers should optimize these to memory ops)
96
97 // These work on object fields in the Java heap.
98 // They will not work on elements of packed arrays.
99
100 /**
101 * Fetches a value from a given Java variable.
102 * More specifically, fetches a field or array element within the given
103 * object {@code o} at the given offset, or (if {@code o} is null)
104 * from the memory address whose numerical value is the given offset.
105 * <p>
106 * The results are undefined unless one of the following cases is true:
107 * <ul>
108 * <li>The offset was obtained from {@link #objectFieldOffset} on
109 * the {@link java.lang.reflect.Field} of some Java field and the object
110 * referred to by {@code o} is of a class compatible with that
111 * field's class.
112 *
113 * <li>The offset and object reference {@code o} (either null or
114 * non-null) were both obtained via {@link #staticFieldOffset}
115 * and {@link #staticFieldBase} (respectively) from the
116 * reflective {@link Field} representation of some Java field.
117 *
118 * <li>The object referred to by {@code o} is an array, and the offset
119 * is an integer of the form {@code B+N*S}, where {@code N} is
120 * a valid index into the array, and {@code B} and {@code S} are
121 * the values obtained by {@link #arrayBaseOffset} and {@link
122 * #arrayIndexScale} (respectively) from the array's class. The value
123 * referred to is the {@code N}<em>th</em> element of the array.
124 *
125 * </ul>
126 * <p>
127 * If one of the above cases is true, the call references a specific Java
128 * variable (field or array element). However, the results are undefined
129 * if that variable is not in fact of the type returned by this method.
130 * <p>
131 * This method refers to a variable by means of two parameters, and so
132 * it provides (in effect) a <em>double-register</em> addressing mode
133 * for Java variables. When the object reference is null, this method
134 * uses its offset as an absolute address. This is similar in operation
135 * to methods such as {@link #getInt(long)}, which provide (in effect) a
136 * <em>single-register</em> addressing mode for non-Java variables.
137 * However, because Java variables may have a different layout in memory
138 * from non-Java variables, programmers should not assume that these
139 * two addressing modes are ever equivalent. Also, programmers should
140 * remember that offsets from the double-register addressing mode cannot
141 * be portably confused with longs used in the single-register addressing
142 * mode.
143 *
144 * @param o Java heap object in which the variable resides, if any, else
145 * null
146 * @param offset indication of where the variable resides in a Java heap
147 * object, if any, else a memory address locating the variable
148 * statically
149 * @return the value fetched from the indicated Java variable
150 * @throws RuntimeException No defined exceptions are thrown, not even
151 * {@link NullPointerException}
152 */
153 @HotSpotIntrinsicCandidate
154 public native int getInt(Object o, long offset);
155
156 /**
157 * Stores a value into a given Java variable.
158 * <p>
159 * The first two parameters are interpreted exactly as with
160 * {@link #getInt(Object, long)} to refer to a specific
161 * Java variable (field or array element). The given value
162 * is stored into that variable.
163 * <p>
164 * The variable must be of the same type as the method
165 * parameter {@code x}.
166 *
167 * @param o Java heap object in which the variable resides, if any, else
168 * null
169 * @param offset indication of where the variable resides in a Java heap
170 * object, if any, else a memory address locating the variable
171 * statically
172 * @param x the value to store into the indicated Java variable
173 * @throws RuntimeException No defined exceptions are thrown, not even
174 * {@link NullPointerException}
175 */
176 @HotSpotIntrinsicCandidate
177 public native void putInt(Object o, long offset, int x);
178
179 /**
180 * Returns true if the given class is a regular value type.
181 */
182 public boolean isValueType(Class<?> c) {
183 return c.isValue() && c == c.asValueType();
184 }
185
186 /**
187 * Returns true if the given class is a flattened array.
188 */
189 public native boolean isFlattenedArray(Class<?> arrayClass);
190
191 /**
192 * Fetches a reference value from a given Java variable.
193 * This method can return a reference to either an object or value
194 * or a null reference.
195 *
196 * @see #getInt(Object, long)
197 */
198 @HotSpotIntrinsicCandidate
199 public native Object getReference(Object o, long offset);
200
201 /**
202 * Stores a reference value into a given Java variable.
203 * This method can store a reference to either an object or value
204 * or a null reference.
205 * <p>
206 * Unless the reference {@code x} being stored is either null
207 * or matches the field type, the results are undefined.
208 * If the reference {@code o} is non-null, card marks or
209 * other store barriers for that object (if the VM requires them)
210 * are updated.
211 * @see #putInt(Object, long, int)
212 */
213 @HotSpotIntrinsicCandidate
214 public native void putReference(Object o, long offset, Object x);
215
216 /**
217 * Fetches a value of type {@code <V>} from a given Java variable.
218 * More specifically, fetches a field or array element within the given
219 * {@code o} object at the given offset, or (if {@code o} is null)
220 * from the memory address whose numerical value is the given offset.
221 *
222 * @param o Java heap object in which the variable resides, if any, else
223 * null
224 * @param offset indication of where the variable resides in a Java heap
225 * object, if any, else a memory address locating the variable
226 * statically
227 * @param vc value class
228 * @param <V> the type of a value
229 * @return the value fetched from the indicated Java variable
230 * @throws RuntimeException No defined exceptions are thrown, not even
231 * {@link NullPointerException}
232 */
233 public native <V> V getValue(Object o, long offset, Class<?> vc);
234
235 /**
236 * Stores the given value into a given Java variable.
237 *
238 * Unless the reference {@code o} being stored is either null
239 * or matches the field type and not in a value container,
240 * the results are undefined.
241 *
242 * @param o Java heap object in which the variable resides, if any, else
243 * null
244 * @param offset indication of where the variable resides in a Java heap
245 * object, if any, else a memory address locating the variable
246 * statically
247 * @param vc value class
248 * @param v the value to store into the indicated Java variable
249 * @param <V> the type of a value
250 * @throws RuntimeException No defined exceptions are thrown, not even
251 * {@link NullPointerException}
252 */
253 public native <V> void putValue(Object o, long offset, Class<?> vc, V v);
254
255 /** @see #getInt(Object, long) */
256 @HotSpotIntrinsicCandidate
257 public native boolean getBoolean(Object o, long offset);
258
259 /** @see #putInt(Object, long, int) */
260 @HotSpotIntrinsicCandidate
261 public native void putBoolean(Object o, long offset, boolean x);
262
263 /** @see #getInt(Object, long) */
264 @HotSpotIntrinsicCandidate
265 public native byte getByte(Object o, long offset);
266
267 /** @see #putInt(Object, long, int) */
268 @HotSpotIntrinsicCandidate
269 public native void putByte(Object o, long offset, byte x);
270
271 /** @see #getInt(Object, long) */
272 @HotSpotIntrinsicCandidate
273 public native short getShort(Object o, long offset);
274
275 /** @see #putInt(Object, long, int) */
276 @HotSpotIntrinsicCandidate
277 public native void putShort(Object o, long offset, short x);
278
279 /** @see #getInt(Object, long) */
280 @HotSpotIntrinsicCandidate
281 public native char getChar(Object o, long offset);
282
283 /** @see #putInt(Object, long, int) */
284 @HotSpotIntrinsicCandidate
285 public native void putChar(Object o, long offset, char x);
286
287 /** @see #getInt(Object, long) */
288 @HotSpotIntrinsicCandidate
289 public native long getLong(Object o, long offset);
290
291 /** @see #putInt(Object, long, int) */
292 @HotSpotIntrinsicCandidate
293 public native void putLong(Object o, long offset, long x);
294
295 /** @see #getInt(Object, long) */
296 @HotSpotIntrinsicCandidate
297 public native float getFloat(Object o, long offset);
298
299 /** @see #putInt(Object, long, int) */
300 @HotSpotIntrinsicCandidate
301 public native void putFloat(Object o, long offset, float x);
302
303 /** @see #getInt(Object, long) */
304 @HotSpotIntrinsicCandidate
305 public native double getDouble(Object o, long offset);
306
307 /** @see #putInt(Object, long, int) */
308 @HotSpotIntrinsicCandidate
309 public native void putDouble(Object o, long offset, double x);
310
311 /**
312 * Fetches a native pointer from a given memory address. If the address is
313 * zero, or does not point into a block obtained from {@link
314 * #allocateMemory}, the results are undefined.
315 *
316 * <p>If the native pointer is less than 64 bits wide, it is extended as
317 * an unsigned number to a Java long. The pointer may be indexed by any
318 * given byte offset, simply by adding that offset (as a simple integer) to
319 * the long representing the pointer. The number of bytes actually read
320 * from the target address may be determined by consulting {@link
321 * #addressSize}.
322 *
323 * @see #allocateMemory
324 * @see #getInt(Object, long)
325 */
326 @ForceInline
327 public long getAddress(Object o, long offset) {
328 if (ADDRESS_SIZE == 4) {
329 return Integer.toUnsignedLong(getInt(o, offset));
330 } else {
331 return getLong(o, offset);
332 }
333 }
334
335 /**
336 * Stores a native pointer into a given memory address. If the address is
337 * zero, or does not point into a block obtained from {@link
338 * #allocateMemory}, the results are undefined.
339 *
340 * <p>The number of bytes actually written at the target address may be
341 * determined by consulting {@link #addressSize}.
342 *
343 * @see #allocateMemory
344 * @see #putInt(Object, long, int)
345 */
346 @ForceInline
347 public void putAddress(Object o, long offset, long x) {
348 if (ADDRESS_SIZE == 4) {
349 putInt(o, offset, (int)x);
350 } else {
351 putLong(o, offset, x);
352 }
353 }
354
355 // These read VM internal data.
356
357 /**
358 * Fetches an uncompressed reference value from a given native variable
359 * ignoring the VM's compressed references mode.
360 *
361 * @param address a memory address locating the variable
362 * @return the value fetched from the indicated native variable
363 */
364 public native Object getUncompressedObject(long address);
365
366 // These work on values in the C heap.
367
368 /**
369 * Fetches a value from a given memory address. If the address is zero, or
370 * does not point into a block obtained from {@link #allocateMemory}, the
371 * results are undefined.
372 *
373 * @see #allocateMemory
374 */
375 @ForceInline
376 public byte getByte(long address) {
377 return getByte(null, address);
378 }
379
380 /**
381 * Stores a value into a given memory address. If the address is zero, or
382 * does not point into a block obtained from {@link #allocateMemory}, the
383 * results are undefined.
384 *
385 * @see #getByte(long)
386 */
387 @ForceInline
388 public void putByte(long address, byte x) {
389 putByte(null, address, x);
390 }
391
392 /** @see #getByte(long) */
393 @ForceInline
394 public short getShort(long address) {
395 return getShort(null, address);
396 }
397
398 /** @see #putByte(long, byte) */
399 @ForceInline
400 public void putShort(long address, short x) {
401 putShort(null, address, x);
402 }
403
404 /** @see #getByte(long) */
405 @ForceInline
406 public char getChar(long address) {
407 return getChar(null, address);
408 }
409
410 /** @see #putByte(long, byte) */
411 @ForceInline
412 public void putChar(long address, char x) {
413 putChar(null, address, x);
414 }
415
416 /** @see #getByte(long) */
417 @ForceInline
418 public int getInt(long address) {
419 return getInt(null, address);
420 }
421
422 /** @see #putByte(long, byte) */
423 @ForceInline
424 public void putInt(long address, int x) {
425 putInt(null, address, x);
426 }
427
428 /** @see #getByte(long) */
429 @ForceInline
430 public long getLong(long address) {
431 return getLong(null, address);
432 }
433
434 /** @see #putByte(long, byte) */
435 @ForceInline
436 public void putLong(long address, long x) {
437 putLong(null, address, x);
438 }
439
440 /** @see #getByte(long) */
441 @ForceInline
442 public float getFloat(long address) {
443 return getFloat(null, address);
444 }
445
446 /** @see #putByte(long, byte) */
447 @ForceInline
448 public void putFloat(long address, float x) {
449 putFloat(null, address, x);
450 }
451
452 /** @see #getByte(long) */
453 @ForceInline
454 public double getDouble(long address) {
455 return getDouble(null, address);
456 }
457
458 /** @see #putByte(long, byte) */
459 @ForceInline
460 public void putDouble(long address, double x) {
461 putDouble(null, address, x);
462 }
463
464 /** @see #getAddress(Object, long) */
465 @ForceInline
466 public long getAddress(long address) {
467 return getAddress(null, address);
468 }
469
470 /** @see #putAddress(Object, long, long) */
471 @ForceInline
472 public void putAddress(long address, long x) {
473 putAddress(null, address, x);
474 }
475
476
477
478 /// helper methods for validating various types of objects/values
479
480 /**
481 * Create an exception reflecting that some of the input was invalid
482 *
483 * <em>Note:</em> It is the resposibility of the caller to make
484 * sure arguments are checked before the methods are called. While
485 * some rudimentary checks are performed on the input, the checks
486 * are best effort and when performance is an overriding priority,
487 * as when methods of this class are optimized by the runtime
488 * compiler, some or all checks (if any) may be elided. Hence, the
489 * caller must not rely on the checks and corresponding
490 * exceptions!
491 *
492 * @return an exception object
493 */
494 private RuntimeException invalidInput() {
495 return new IllegalArgumentException();
496 }
497
498 /**
499 * Check if a value is 32-bit clean (32 MSB are all zero)
500 *
501 * @param value the 64-bit value to check
502 *
503 * @return true if the value is 32-bit clean
504 */
505 private boolean is32BitClean(long value) {
506 return value >>> 32 == 0;
507 }
508
509 /**
510 * Check the validity of a size (the equivalent of a size_t)
511 *
512 * @throws RuntimeException if the size is invalid
513 * (<em>Note:</em> after optimization, invalid inputs may
514 * go undetected, which will lead to unpredictable
515 * behavior)
516 */
517 private void checkSize(long size) {
518 if (ADDRESS_SIZE == 4) {
519 // Note: this will also check for negative sizes
520 if (!is32BitClean(size)) {
521 throw invalidInput();
522 }
523 } else if (size < 0) {
524 throw invalidInput();
525 }
526 }
527
528 /**
529 * Check the validity of a native address (the equivalent of void*)
530 *
531 * @throws RuntimeException if the address is invalid
532 * (<em>Note:</em> after optimization, invalid inputs may
533 * go undetected, which will lead to unpredictable
534 * behavior)
535 */
536 private void checkNativeAddress(long address) {
537 if (ADDRESS_SIZE == 4) {
538 // Accept both zero and sign extended pointers. A valid
539 // pointer will, after the +1 below, either have produced
540 // the value 0x0 or 0x1. Masking off the low bit allows
541 // for testing against 0.
542 if ((((address >> 32) + 1) & ~1) != 0) {
543 throw invalidInput();
544 }
545 }
546 }
547
548 /**
549 * Check the validity of an offset, relative to a base object
550 *
551 * @param o the base object
552 * @param offset the offset to check
553 *
554 * @throws RuntimeException if the size is invalid
555 * (<em>Note:</em> after optimization, invalid inputs may
556 * go undetected, which will lead to unpredictable
557 * behavior)
558 */
559 private void checkOffset(Object o, long offset) {
560 if (ADDRESS_SIZE == 4) {
561 // Note: this will also check for negative offsets
562 if (!is32BitClean(offset)) {
563 throw invalidInput();
564 }
565 } else if (offset < 0) {
566 throw invalidInput();
567 }
568 }
569
570 /**
571 * Check the validity of a double-register pointer
572 *
573 * Note: This code deliberately does *not* check for NPE for (at
574 * least) three reasons:
575 *
576 * 1) NPE is not just NULL/0 - there is a range of values all
577 * resulting in an NPE, which is not trivial to check for
578 *
579 * 2) It is the responsibility of the callers of Unsafe methods
580 * to verify the input, so throwing an exception here is not really
581 * useful - passing in a NULL pointer is a critical error and the
582 * must not expect an exception to be thrown anyway.
583 *
584 * 3) the actual operations will detect NULL pointers anyway by
585 * means of traps and signals (like SIGSEGV).
586 *
587 * @param o Java heap object, or null
588 * @param offset indication of where the variable resides in a Java heap
589 * object, if any, else a memory address locating the variable
590 * statically
591 *
592 * @throws RuntimeException if the pointer is invalid
593 * (<em>Note:</em> after optimization, invalid inputs may
594 * go undetected, which will lead to unpredictable
595 * behavior)
596 */
597 private void checkPointer(Object o, long offset) {
598 if (o == null) {
599 checkNativeAddress(offset);
600 } else {
601 checkOffset(o, offset);
602 }
603 }
604
605 /**
606 * Check if a type is a primitive array type
607 *
608 * @param c the type to check
609 *
610 * @return true if the type is a primitive array type
611 */
612 private void checkPrimitiveArray(Class<?> c) {
613 Class<?> componentType = c.getComponentType();
614 if (componentType == null || !componentType.isPrimitive()) {
615 throw invalidInput();
616 }
617 }
618
619 /**
620 * Check that a pointer is a valid primitive array type pointer
621 *
622 * Note: pointers off-heap are considered to be primitive arrays
623 *
624 * @throws RuntimeException if the pointer is invalid
625 * (<em>Note:</em> after optimization, invalid inputs may
626 * go undetected, which will lead to unpredictable
627 * behavior)
628 */
629 private void checkPrimitivePointer(Object o, long offset) {
630 checkPointer(o, offset);
631
632 if (o != null) {
633 // If on heap, it must be a primitive array
634 checkPrimitiveArray(o.getClass());
635 }
636 }
637
638
639 /// wrappers for malloc, realloc, free:
640
641 /**
642 * Allocates a new block of native memory, of the given size in bytes. The
643 * contents of the memory are uninitialized; they will generally be
644 * garbage. The resulting native pointer will never be zero, and will be
645 * aligned for all value types. Dispose of this memory by calling {@link
646 * #freeMemory}, or resize it with {@link #reallocateMemory}.
647 *
648 * <em>Note:</em> It is the resposibility of the caller to make
649 * sure arguments are checked before the methods are called. While
650 * some rudimentary checks are performed on the input, the checks
651 * are best effort and when performance is an overriding priority,
652 * as when methods of this class are optimized by the runtime
653 * compiler, some or all checks (if any) may be elided. Hence, the
654 * caller must not rely on the checks and corresponding
655 * exceptions!
656 *
657 * @throws RuntimeException if the size is negative or too large
658 * for the native size_t type
659 *
660 * @throws OutOfMemoryError if the allocation is refused by the system
661 *
662 * @see #getByte(long)
663 * @see #putByte(long, byte)
664 */
665 public long allocateMemory(long bytes) {
666 allocateMemoryChecks(bytes);
667
668 if (bytes == 0) {
669 return 0;
670 }
671
672 long p = allocateMemory0(bytes);
673 if (p == 0) {
674 throw new OutOfMemoryError();
675 }
676
677 return p;
678 }
679
680 /**
681 * Validate the arguments to allocateMemory
682 *
683 * @throws RuntimeException if the arguments are invalid
684 * (<em>Note:</em> after optimization, invalid inputs may
685 * go undetected, which will lead to unpredictable
686 * behavior)
687 */
688 private void allocateMemoryChecks(long bytes) {
689 checkSize(bytes);
690 }
691
692 /**
693 * Resizes a new block of native memory, to the given size in bytes. The
694 * contents of the new block past the size of the old block are
695 * uninitialized; they will generally be garbage. The resulting native
696 * pointer will be zero if and only if the requested size is zero. The
697 * resulting native pointer will be aligned for all value types. Dispose
698 * of this memory by calling {@link #freeMemory}, or resize it with {@link
699 * #reallocateMemory}. The address passed to this method may be null, in
700 * which case an allocation will be performed.
701 *
702 * <em>Note:</em> It is the resposibility of the caller to make
703 * sure arguments are checked before the methods are called. While
704 * some rudimentary checks are performed on the input, the checks
705 * are best effort and when performance is an overriding priority,
706 * as when methods of this class are optimized by the runtime
707 * compiler, some or all checks (if any) may be elided. Hence, the
708 * caller must not rely on the checks and corresponding
709 * exceptions!
710 *
711 * @throws RuntimeException if the size is negative or too large
712 * for the native size_t type
713 *
714 * @throws OutOfMemoryError if the allocation is refused by the system
715 *
716 * @see #allocateMemory
717 */
718 public long reallocateMemory(long address, long bytes) {
719 reallocateMemoryChecks(address, bytes);
720
721 if (bytes == 0) {
722 freeMemory(address);
723 return 0;
724 }
725
726 long p = (address == 0) ? allocateMemory0(bytes) : reallocateMemory0(address, bytes);
727 if (p == 0) {
728 throw new OutOfMemoryError();
729 }
730
731 return p;
732 }
733
734 /**
735 * Validate the arguments to reallocateMemory
736 *
737 * @throws RuntimeException if the arguments are invalid
738 * (<em>Note:</em> after optimization, invalid inputs may
739 * go undetected, which will lead to unpredictable
740 * behavior)
741 */
742 private void reallocateMemoryChecks(long address, long bytes) {
743 checkPointer(null, address);
744 checkSize(bytes);
745 }
746
747 /**
748 * Sets all bytes in a given block of memory to a fixed value
749 * (usually zero).
750 *
751 * <p>This method determines a block's base address by means of two parameters,
752 * and so it provides (in effect) a <em>double-register</em> addressing mode,
753 * as discussed in {@link #getInt(Object,long)}. When the object reference is null,
754 * the offset supplies an absolute base address.
755 *
756 * <p>The stores are in coherent (atomic) units of a size determined
757 * by the address and length parameters. If the effective address and
758 * length are all even modulo 8, the stores take place in 'long' units.
759 * If the effective address and length are (resp.) even modulo 4 or 2,
760 * the stores take place in units of 'int' or 'short'.
761 *
762 * <em>Note:</em> It is the resposibility of the caller to make
763 * sure arguments are checked before the methods are called. While
764 * some rudimentary checks are performed on the input, the checks
765 * are best effort and when performance is an overriding priority,
766 * as when methods of this class are optimized by the runtime
767 * compiler, some or all checks (if any) may be elided. Hence, the
768 * caller must not rely on the checks and corresponding
769 * exceptions!
770 *
771 * @throws RuntimeException if any of the arguments is invalid
772 *
773 * @since 1.7
774 */
775 public void setMemory(Object o, long offset, long bytes, byte value) {
776 setMemoryChecks(o, offset, bytes, value);
777
778 if (bytes == 0) {
779 return;
780 }
781
782 setMemory0(o, offset, bytes, value);
783 }
784
785 /**
786 * Sets all bytes in a given block of memory to a fixed value
787 * (usually zero). This provides a <em>single-register</em> addressing mode,
788 * as discussed in {@link #getInt(Object,long)}.
789 *
790 * <p>Equivalent to {@code setMemory(null, address, bytes, value)}.
791 */
792 public void setMemory(long address, long bytes, byte value) {
793 setMemory(null, address, bytes, value);
794 }
795
796 /**
797 * Validate the arguments to setMemory
798 *
799 * @throws RuntimeException if the arguments are invalid
800 * (<em>Note:</em> after optimization, invalid inputs may
801 * go undetected, which will lead to unpredictable
802 * behavior)
803 */
804 private void setMemoryChecks(Object o, long offset, long bytes, byte value) {
805 checkPrimitivePointer(o, offset);
806 checkSize(bytes);
807 }
808
809 /**
810 * Sets all bytes in a given block of memory to a copy of another
811 * block.
812 *
813 * <p>This method determines each block's base address by means of two parameters,
814 * and so it provides (in effect) a <em>double-register</em> addressing mode,
815 * as discussed in {@link #getInt(Object,long)}. When the object reference is null,
816 * the offset supplies an absolute base address.
817 *
818 * <p>The transfers are in coherent (atomic) units of a size determined
819 * by the address and length parameters. If the effective addresses and
820 * length are all even modulo 8, the transfer takes place in 'long' units.
821 * If the effective addresses and length are (resp.) even modulo 4 or 2,
822 * the transfer takes place in units of 'int' or 'short'.
823 *
824 * <em>Note:</em> It is the resposibility of the caller to make
825 * sure arguments are checked before the methods are called. While
826 * some rudimentary checks are performed on the input, the checks
827 * are best effort and when performance is an overriding priority,
828 * as when methods of this class are optimized by the runtime
829 * compiler, some or all checks (if any) may be elided. Hence, the
830 * caller must not rely on the checks and corresponding
831 * exceptions!
832 *
833 * @throws RuntimeException if any of the arguments is invalid
834 *
835 * @since 1.7
836 */
837 public void copyMemory(Object srcBase, long srcOffset,
838 Object destBase, long destOffset,
839 long bytes) {
840 copyMemoryChecks(srcBase, srcOffset, destBase, destOffset, bytes);
841
842 if (bytes == 0) {
843 return;
844 }
845
846 copyMemory0(srcBase, srcOffset, destBase, destOffset, bytes);
847 }
848
849 /**
850 * Sets all bytes in a given block of memory to a copy of another
851 * block. This provides a <em>single-register</em> addressing mode,
852 * as discussed in {@link #getInt(Object,long)}.
853 *
854 * Equivalent to {@code copyMemory(null, srcAddress, null, destAddress, bytes)}.
855 */
856 public void copyMemory(long srcAddress, long destAddress, long bytes) {
857 copyMemory(null, srcAddress, null, destAddress, bytes);
858 }
859
860 /**
861 * Validate the arguments to copyMemory
862 *
863 * @throws RuntimeException if any of the arguments is invalid
864 * (<em>Note:</em> after optimization, invalid inputs may
865 * go undetected, which will lead to unpredictable
866 * behavior)
867 */
868 private void copyMemoryChecks(Object srcBase, long srcOffset,
869 Object destBase, long destOffset,
870 long bytes) {
871 checkSize(bytes);
872 checkPrimitivePointer(srcBase, srcOffset);
873 checkPrimitivePointer(destBase, destOffset);
874 }
875
876 /**
877 * Copies all elements from one block of memory to another block,
878 * *unconditionally* byte swapping the elements on the fly.
879 *
880 * <p>This method determines each block's base address by means of two parameters,
881 * and so it provides (in effect) a <em>double-register</em> addressing mode,
882 * as discussed in {@link #getInt(Object,long)}. When the object reference is null,
883 * the offset supplies an absolute base address.
884 *
885 * <em>Note:</em> It is the resposibility of the caller to make
886 * sure arguments are checked before the methods are called. While
887 * some rudimentary checks are performed on the input, the checks
888 * are best effort and when performance is an overriding priority,
889 * as when methods of this class are optimized by the runtime
890 * compiler, some or all checks (if any) may be elided. Hence, the
891 * caller must not rely on the checks and corresponding
892 * exceptions!
893 *
894 * @throws RuntimeException if any of the arguments is invalid
895 *
896 * @since 9
897 */
898 public void copySwapMemory(Object srcBase, long srcOffset,
899 Object destBase, long destOffset,
900 long bytes, long elemSize) {
901 copySwapMemoryChecks(srcBase, srcOffset, destBase, destOffset, bytes, elemSize);
902
903 if (bytes == 0) {
904 return;
905 }
906
907 copySwapMemory0(srcBase, srcOffset, destBase, destOffset, bytes, elemSize);
908 }
909
910 private void copySwapMemoryChecks(Object srcBase, long srcOffset,
911 Object destBase, long destOffset,
912 long bytes, long elemSize) {
913 checkSize(bytes);
914
915 if (elemSize != 2 && elemSize != 4 && elemSize != 8) {
916 throw invalidInput();
917 }
918 if (bytes % elemSize != 0) {
919 throw invalidInput();
920 }
921
922 checkPrimitivePointer(srcBase, srcOffset);
923 checkPrimitivePointer(destBase, destOffset);
924 }
925
926 /**
927 * Copies all elements from one block of memory to another block, byte swapping the
928 * elements on the fly.
929 *
930 * This provides a <em>single-register</em> addressing mode, as
931 * discussed in {@link #getInt(Object,long)}.
932 *
933 * Equivalent to {@code copySwapMemory(null, srcAddress, null, destAddress, bytes, elemSize)}.
934 */
935 public void copySwapMemory(long srcAddress, long destAddress, long bytes, long elemSize) {
936 copySwapMemory(null, srcAddress, null, destAddress, bytes, elemSize);
937 }
938
939 /**
940 * Disposes of a block of native memory, as obtained from {@link
941 * #allocateMemory} or {@link #reallocateMemory}. The address passed to
942 * this method may be null, in which case no action is taken.
943 *
944 * <em>Note:</em> It is the resposibility of the caller to make
945 * sure arguments are checked before the methods are called. While
946 * some rudimentary checks are performed on the input, the checks
947 * are best effort and when performance is an overriding priority,
948 * as when methods of this class are optimized by the runtime
949 * compiler, some or all checks (if any) may be elided. Hence, the
950 * caller must not rely on the checks and corresponding
951 * exceptions!
952 *
953 * @throws RuntimeException if any of the arguments is invalid
954 *
955 * @see #allocateMemory
956 */
957 public void freeMemory(long address) {
958 freeMemoryChecks(address);
959
960 if (address == 0) {
961 return;
962 }
963
964 freeMemory0(address);
965 }
966
967 /**
968 * Validate the arguments to freeMemory
969 *
970 * @throws RuntimeException if the arguments are invalid
971 * (<em>Note:</em> after optimization, invalid inputs may
972 * go undetected, which will lead to unpredictable
973 * behavior)
974 */
975 private void freeMemoryChecks(long address) {
976 checkPointer(null, address);
977 }
978
979 /// random queries
980
981 /**
982 * This constant differs from all results that will ever be returned from
983 * {@link #staticFieldOffset}, {@link #objectFieldOffset},
984 * or {@link #arrayBaseOffset}.
985 */
986 public static final int INVALID_FIELD_OFFSET = -1;
987
988 /**
989 * Reports the location of a given field in the storage allocation of its
990 * class. Do not expect to perform any sort of arithmetic on this offset;
991 * it is just a cookie which is passed to the unsafe heap memory accessors.
992 *
993 * <p>Any given field will always have the same offset and base, and no
994 * two distinct fields of the same class will ever have the same offset
995 * and base.
996 *
997 * <p>As of 1.4.1, offsets for fields are represented as long values,
998 * although the Sun JVM does not use the most significant 32 bits.
999 * However, JVM implementations which store static fields at absolute
1000 * addresses can use long offsets and null base pointers to express
1001 * the field locations in a form usable by {@link #getInt(Object,long)}.
1002 * Therefore, code which will be ported to such JVMs on 64-bit platforms
1003 * must preserve all bits of static field offsets.
1004 * @see #getInt(Object, long)
1005 */
1006 public long objectFieldOffset(Field f) {
1007 if (f == null) {
1008 throw new NullPointerException();
1009 }
1010
1011 return objectFieldOffset0(f);
1012 }
1013
1014 /**
1015 * Reports the location of the field with a given name in the storage
1016 * allocation of its class.
1017 *
1018 * @throws NullPointerException if any parameter is {@code null}.
1019 * @throws InternalError if there is no field named {@code name} declared
1020 * in class {@code c}, i.e., if {@code c.getDeclaredField(name)}
1021 * would throw {@code java.lang.NoSuchFieldException}.
1022 *
1023 * @see #objectFieldOffset(Field)
1024 */
1025 public long objectFieldOffset(Class<?> c, String name) {
1026 if (c == null || name == null) {
1027 throw new NullPointerException();
1028 }
1029
1030 return objectFieldOffset1(c, name);
1031 }
1032
1033 /**
1034 * Reports the location of a given static field, in conjunction with {@link
1035 * #staticFieldBase}.
1036 * <p>Do not expect to perform any sort of arithmetic on this offset;
1037 * it is just a cookie which is passed to the unsafe heap memory accessors.
1038 *
1039 * <p>Any given field will always have the same offset, and no two distinct
1040 * fields of the same class will ever have the same offset.
1041 *
1042 * <p>As of 1.4.1, offsets for fields are represented as long values,
1043 * although the Sun JVM does not use the most significant 32 bits.
1044 * It is hard to imagine a JVM technology which needs more than
1045 * a few bits to encode an offset within a non-array object,
1046 * However, for consistency with other methods in this class,
1047 * this method reports its result as a long value.
1048 * @see #getInt(Object, long)
1049 */
1050 public long staticFieldOffset(Field f) {
1051 if (f == null) {
1052 throw new NullPointerException();
1053 }
1054
1055 return staticFieldOffset0(f);
1056 }
1057
1058 /**
1059 * Reports the location of a given static field, in conjunction with {@link
1060 * #staticFieldOffset}.
1061 * <p>Fetch the base "Object", if any, with which static fields of the
1062 * given class can be accessed via methods like {@link #getInt(Object,
1063 * long)}. This value may be null. This value may refer to an object
1064 * which is a "cookie", not guaranteed to be a real Object, and it should
1065 * not be used in any way except as argument to the get and put routines in
1066 * this class.
1067 */
1068 public Object staticFieldBase(Field f) {
1069 if (f == null) {
1070 throw new NullPointerException();
1071 }
1072
1073 return staticFieldBase0(f);
1074 }
1075
1076 /**
1077 * Detects if the given class may need to be initialized. This is often
1078 * needed in conjunction with obtaining the static field base of a
1079 * class.
1080 * @return false only if a call to {@code ensureClassInitialized} would have no effect
1081 */
1082 public boolean shouldBeInitialized(Class<?> c) {
1083 if (c == null) {
1084 throw new NullPointerException();
1085 }
1086
1087 return shouldBeInitialized0(c);
1088 }
1089
1090 /**
1091 * Ensures the given class has been initialized. This is often
1092 * needed in conjunction with obtaining the static field base of a
1093 * class.
1094 */
1095 public void ensureClassInitialized(Class<?> c) {
1096 if (c == null) {
1097 throw new NullPointerException();
1098 }
1099
1100 ensureClassInitialized0(c);
1101 }
1102
1103 /**
1104 * Reports the offset of the first element in the storage allocation of a
1105 * given array class. If {@link #arrayIndexScale} returns a non-zero value
1106 * for the same class, you may use that scale factor, together with this
1107 * base offset, to form new offsets to access elements of arrays of the
1108 * given class.
1109 *
1110 * @see #getInt(Object, long)
1111 * @see #putInt(Object, long, int)
1112 */
1113 public int arrayBaseOffset(Class<?> arrayClass) {
1114 if (arrayClass == null) {
1115 throw new NullPointerException();
1116 }
1117
1118 return arrayBaseOffset0(arrayClass);
1119 }
1120
1121
1122 /** The value of {@code arrayBaseOffset(boolean[].class)} */
1123 public static final int ARRAY_BOOLEAN_BASE_OFFSET
1124 = theUnsafe.arrayBaseOffset(boolean[].class);
1125
1126 /** The value of {@code arrayBaseOffset(byte[].class)} */
1127 public static final int ARRAY_BYTE_BASE_OFFSET
1128 = theUnsafe.arrayBaseOffset(byte[].class);
1129
1130 /** The value of {@code arrayBaseOffset(short[].class)} */
1131 public static final int ARRAY_SHORT_BASE_OFFSET
1132 = theUnsafe.arrayBaseOffset(short[].class);
1133
1134 /** The value of {@code arrayBaseOffset(char[].class)} */
1135 public static final int ARRAY_CHAR_BASE_OFFSET
1136 = theUnsafe.arrayBaseOffset(char[].class);
1137
1138 /** The value of {@code arrayBaseOffset(int[].class)} */
1139 public static final int ARRAY_INT_BASE_OFFSET
1140 = theUnsafe.arrayBaseOffset(int[].class);
1141
1142 /** The value of {@code arrayBaseOffset(long[].class)} */
1143 public static final int ARRAY_LONG_BASE_OFFSET
1144 = theUnsafe.arrayBaseOffset(long[].class);
1145
1146 /** The value of {@code arrayBaseOffset(float[].class)} */
1147 public static final int ARRAY_FLOAT_BASE_OFFSET
1148 = theUnsafe.arrayBaseOffset(float[].class);
1149
1150 /** The value of {@code arrayBaseOffset(double[].class)} */
1151 public static final int ARRAY_DOUBLE_BASE_OFFSET
1152 = theUnsafe.arrayBaseOffset(double[].class);
1153
1154 /** The value of {@code arrayBaseOffset(Object[].class)} */
1155 public static final int ARRAY_OBJECT_BASE_OFFSET
1156 = theUnsafe.arrayBaseOffset(Object[].class);
1157
1158 /**
1159 * Reports the scale factor for addressing elements in the storage
1160 * allocation of a given array class. However, arrays of "narrow" types
1161 * will generally not work properly with accessors like {@link
1162 * #getByte(Object, long)}, so the scale factor for such classes is reported
1163 * as zero.
1164 *
1165 * @see #arrayBaseOffset
1166 * @see #getInt(Object, long)
1167 * @see #putInt(Object, long, int)
1168 */
1169 public int arrayIndexScale(Class<?> arrayClass) {
1170 if (arrayClass == null) {
1171 throw new NullPointerException();
1172 }
1173
1174 return arrayIndexScale0(arrayClass);
1175 }
1176
1177
1178 /** The value of {@code arrayIndexScale(boolean[].class)} */
1179 public static final int ARRAY_BOOLEAN_INDEX_SCALE
1180 = theUnsafe.arrayIndexScale(boolean[].class);
1181
1182 /** The value of {@code arrayIndexScale(byte[].class)} */
1183 public static final int ARRAY_BYTE_INDEX_SCALE
1184 = theUnsafe.arrayIndexScale(byte[].class);
1185
1186 /** The value of {@code arrayIndexScale(short[].class)} */
1187 public static final int ARRAY_SHORT_INDEX_SCALE
1188 = theUnsafe.arrayIndexScale(short[].class);
1189
1190 /** The value of {@code arrayIndexScale(char[].class)} */
1191 public static final int ARRAY_CHAR_INDEX_SCALE
1192 = theUnsafe.arrayIndexScale(char[].class);
1193
1194 /** The value of {@code arrayIndexScale(int[].class)} */
1195 public static final int ARRAY_INT_INDEX_SCALE
1196 = theUnsafe.arrayIndexScale(int[].class);
1197
1198 /** The value of {@code arrayIndexScale(long[].class)} */
1199 public static final int ARRAY_LONG_INDEX_SCALE
1200 = theUnsafe.arrayIndexScale(long[].class);
1201
1202 /** The value of {@code arrayIndexScale(float[].class)} */
1203 public static final int ARRAY_FLOAT_INDEX_SCALE
1204 = theUnsafe.arrayIndexScale(float[].class);
1205
1206 /** The value of {@code arrayIndexScale(double[].class)} */
1207 public static final int ARRAY_DOUBLE_INDEX_SCALE
1208 = theUnsafe.arrayIndexScale(double[].class);
1209
1210 /** The value of {@code arrayIndexScale(Object[].class)} */
1211 public static final int ARRAY_OBJECT_INDEX_SCALE
1212 = theUnsafe.arrayIndexScale(Object[].class);
1213
1214 /**
1215 * Reports the size in bytes of a native pointer, as stored via {@link
1216 * #putAddress}. This value will be either 4 or 8. Note that the sizes of
1217 * other primitive types (as stored in native memory blocks) is determined
1218 * fully by their information content.
1219 */
1220 public int addressSize() {
1221 return ADDRESS_SIZE;
1222 }
1223
1224 /** The value of {@code addressSize()} */
1225 public static final int ADDRESS_SIZE = theUnsafe.addressSize0();
1226
1227 /**
1228 * Reports the size in bytes of a native memory page (whatever that is).
1229 * This value will always be a power of two.
1230 */
1231 public native int pageSize();
1232
1233
1234 /// random trusted operations from JNI:
1235
1236 /**
1237 * Tells the VM to define a class, without security checks. By default, the
1238 * class loader and protection domain come from the caller's class.
1239 */
1240 public Class<?> defineClass(String name, byte[] b, int off, int len,
1241 ClassLoader loader,
1242 ProtectionDomain protectionDomain) {
1243 if (b == null) {
1244 throw new NullPointerException();
1245 }
1246 if (len < 0) {
1247 throw new ArrayIndexOutOfBoundsException();
1248 }
1249
1250 return defineClass0(name, b, off, len, loader, protectionDomain);
1251 }
1252
1253 public native Class<?> defineClass0(String name, byte[] b, int off, int len,
1254 ClassLoader loader,
1255 ProtectionDomain protectionDomain);
1256
1257 /**
1258 * Defines a class but does not make it known to the class loader or system dictionary.
1259 * <p>
1260 * For each CP entry, the corresponding CP patch must either be null or have
1261 * the a format that matches its tag:
1262 * <ul>
1263 * <li>Integer, Long, Float, Double: the corresponding wrapper object type from java.lang
1264 * <li>Utf8: a string (must have suitable syntax if used as signature or name)
1265 * <li>Class: any java.lang.Class object
1266 * <li>String: any object (not just a java.lang.String)
1267 * <li>InterfaceMethodRef: (NYI) a method handle to invoke on that call site's arguments
1268 * </ul>
1269 * @param hostClass context for linkage, access control, protection domain, and class loader
1270 * @param data bytes of a class file
1271 * @param cpPatches where non-null entries exist, they replace corresponding CP entries in data
1272 */
1273 public Class<?> defineAnonymousClass(Class<?> hostClass, byte[] data, Object[] cpPatches) {
1274 if (hostClass == null || data == null) {
1275 throw new NullPointerException();
1276 }
1277 if (hostClass.isArray() || hostClass.isPrimitive()) {
1278 throw new IllegalArgumentException();
1279 }
1280
1281 return defineAnonymousClass0(hostClass, data, cpPatches);
1282 }
1283
1284 /**
1285 * Allocates an instance but does not run any constructor.
1286 * Initializes the class if it has not yet been.
1287 */
1288 @HotSpotIntrinsicCandidate
1289 public native Object allocateInstance(Class<?> cls)
1290 throws InstantiationException;
1291
1292 /**
1293 * Allocates an array of a given type, but does not do zeroing.
1294 * <p>
1295 * This method should only be used in the very rare cases where a high-performance code
1296 * overwrites the destination array completely, and compilers cannot assist in zeroing elimination.
1297 * In an overwhelming majority of cases, a normal Java allocation should be used instead.
1298 * <p>
1299 * Users of this method are <b>required</b> to overwrite the initial (garbage) array contents
1300 * before allowing untrusted code, or code in other threads, to observe the reference
1301 * to the newly allocated array. In addition, the publication of the array reference must be
1302 * safe according to the Java Memory Model requirements.
1303 * <p>
1304 * The safest approach to deal with an uninitialized array is to keep the reference to it in local
1305 * variable at least until the initialization is complete, and then publish it <b>once</b>, either
1306 * by writing it to a <em>volatile</em> field, or storing it into a <em>final</em> field in constructor,
1307 * or issuing a {@link #storeFence} before publishing the reference.
1308 * <p>
1309 * @implnote This method can only allocate primitive arrays, to avoid garbage reference
1310 * elements that could break heap integrity.
1311 *
1312 * @param componentType array component type to allocate
1313 * @param length array size to allocate
1314 * @throws IllegalArgumentException if component type is null, or not a primitive class;
1315 * or the length is negative
1316 */
1317 public Object allocateUninitializedArray(Class<?> componentType, int length) {
1318 if (componentType == null) {
1319 throw new IllegalArgumentException("Component type is null");
1320 }
1321 if (!componentType.isPrimitive()) {
1322 throw new IllegalArgumentException("Component type is not primitive");
1323 }
1324 if (length < 0) {
1325 throw new IllegalArgumentException("Negative length");
1326 }
1327 return allocateUninitializedArray0(componentType, length);
1328 }
1329
1330 @HotSpotIntrinsicCandidate
1331 private Object allocateUninitializedArray0(Class<?> componentType, int length) {
1332 // These fallbacks provide zeroed arrays, but intrinsic is not required to
1333 // return the zeroed arrays.
1334 if (componentType == byte.class) return new byte[length];
1335 if (componentType == boolean.class) return new boolean[length];
1336 if (componentType == short.class) return new short[length];
1337 if (componentType == char.class) return new char[length];
1338 if (componentType == int.class) return new int[length];
1339 if (componentType == float.class) return new float[length];
1340 if (componentType == long.class) return new long[length];
1341 if (componentType == double.class) return new double[length];
1342 return null;
1343 }
1344
1345 /** Throws the exception without telling the verifier. */
1346 public native void throwException(Throwable ee);
1347
1348 /**
1349 * Atomically updates Java variable to {@code x} if it is currently
1350 * holding {@code expected}.
1351 *
1352 * <p>This operation has memory semantics of a {@code volatile} read
1353 * and write. Corresponds to C11 atomic_compare_exchange_strong.
1354 *
1355 * @return {@code true} if successful
1356 */
1357 @HotSpotIntrinsicCandidate
1358 public final native boolean compareAndSetReference(Object o, long offset,
1359 Object expected,
1360 Object x);
1361
1362 @ForceInline
1363 public final <V> boolean compareAndSetValue(Object o, long offset,
1364 Class<?> valueType,
1365 V expected,
1366 V x) {
1367 synchronized (valueLock) {
1368 Object witness = getValue(o, offset, valueType);
1369 if (witness.equals(expected)) {
1370 putValue(o, offset, valueType, x);
1371 return true;
1372 }
1373 else {
1374 return false;
1375 }
1376 }
1377 }
1378
1379 @HotSpotIntrinsicCandidate
1380 public final native Object compareAndExchangeReference(Object o, long offset,
1381 Object expected,
1382 Object x);
1383 @ForceInline
1384 public final <V> Object compareAndExchangeValue(Object o, long offset,
1385 Class<?> valueType,
1386 V expected,
1387 V x) {
1388 synchronized (valueLock) {
1389 Object witness = getValue(o, offset, valueType);
1390 if (witness.equals(expected)) {
1391 putValue(o, offset, valueType, x);
1392 }
1393 return witness;
1394 }
1395 }
1396
1397 @HotSpotIntrinsicCandidate
1398 public final Object compareAndExchangeReferenceAcquire(Object o, long offset,
1399 Object expected,
1400 Object x) {
1401 return compareAndExchangeReference(o, offset, expected, x);
1402 }
1403
1404 @ForceInline
1405 public final <V> Object compareAndExchangeValueAcquire(Object o, long offset,
1406 Class<?> valueType,
1407 V expected,
1408 V x) {
1409 return compareAndExchangeValue(o, offset, valueType, expected, x);
1410 }
1411
1412 @HotSpotIntrinsicCandidate
1413 public final Object compareAndExchangeReferenceRelease(Object o, long offset,
1414 Object expected,
1415 Object x) {
1416 return compareAndExchangeReference(o, offset, expected, x);
1417 }
1418
1419 @ForceInline
1420 public final <V> Object compareAndExchangeValueRelease(Object o, long offset,
1421 Class<?> valueType,
1422 V expected,
1423 V x) {
1424 return compareAndExchangeValue(o, offset, valueType, expected, x);
1425 }
1426
1427 @HotSpotIntrinsicCandidate
1428 public final boolean weakCompareAndSetReferencePlain(Object o, long offset,
1429 Object expected,
1430 Object x) {
1431 return compareAndSetReference(o, offset, expected, x);
1432 }
1433
1434 @ForceInline
1435 public final <V> boolean weakCompareAndSetValuePlain(Object o, long offset,
1436 Class<?> valueType,
1437 V expected,
1438 V x) {
1439 return compareAndSetValue(o, offset, valueType, expected, x);
1440 }
1441
1442 @HotSpotIntrinsicCandidate
1443 public final boolean weakCompareAndSetReferenceAcquire(Object o, long offset,
1444 Object expected,
1445 Object x) {
1446 return compareAndSetReference(o, offset, expected, x);
1447 }
1448
1449 @ForceInline
1450 public final <V> boolean weakCompareAndSetValueAcquire(Object o, long offset,
1451 Class<?> valueType,
1452 V expected,
1453 V x) {
1454 return compareAndSetValue(o, offset, valueType, expected, x);
1455 }
1456
1457 @HotSpotIntrinsicCandidate
1458 public final boolean weakCompareAndSetReferenceRelease(Object o, long offset,
1459 Object expected,
1460 Object x) {
1461 return compareAndSetReference(o, offset, expected, x);
1462 }
1463
1464 @ForceInline
1465 public final <V> boolean weakCompareAndSetValueRelease(Object o, long offset,
1466 Class<?> valueType,
1467 V expected,
1468 V x) {
1469 return compareAndSetValue(o, offset, valueType, expected, x);
1470 }
1471
1472 @HotSpotIntrinsicCandidate
1473 public final boolean weakCompareAndSetReference(Object o, long offset,
1474 Object expected,
1475 Object x) {
1476 return compareAndSetReference(o, offset, expected, x);
1477 }
1478
1479 @ForceInline
1480 public final <V> boolean weakCompareAndSetValue(Object o, long offset,
1481 Class<?> valueType,
1482 V expected,
1483 V x) {
1484 return compareAndSetValue(o, offset, valueType, expected, x);
1485 }
1486
1487 /**
1488 * Atomically updates Java variable to {@code x} if it is currently
1489 * holding {@code expected}.
1490 *
1491 * <p>This operation has memory semantics of a {@code volatile} read
1492 * and write. Corresponds to C11 atomic_compare_exchange_strong.
1493 *
1494 * @return {@code true} if successful
1495 */
1496 @HotSpotIntrinsicCandidate
1497 public final native boolean compareAndSetInt(Object o, long offset,
1498 int expected,
1499 int x);
1500
1501 @HotSpotIntrinsicCandidate
1502 public final native int compareAndExchangeInt(Object o, long offset,
1503 int expected,
1504 int x);
1505
1506 @HotSpotIntrinsicCandidate
1507 public final int compareAndExchangeIntAcquire(Object o, long offset,
1508 int expected,
1509 int x) {
1510 return compareAndExchangeInt(o, offset, expected, x);
1511 }
1512
1513 @HotSpotIntrinsicCandidate
1514 public final int compareAndExchangeIntRelease(Object o, long offset,
1515 int expected,
1516 int x) {
1517 return compareAndExchangeInt(o, offset, expected, x);
1518 }
1519
1520 @HotSpotIntrinsicCandidate
1521 public final boolean weakCompareAndSetIntPlain(Object o, long offset,
1522 int expected,
1523 int x) {
1524 return compareAndSetInt(o, offset, expected, x);
1525 }
1526
1527 @HotSpotIntrinsicCandidate
1528 public final boolean weakCompareAndSetIntAcquire(Object o, long offset,
1529 int expected,
1530 int x) {
1531 return compareAndSetInt(o, offset, expected, x);
1532 }
1533
1534 @HotSpotIntrinsicCandidate
1535 public final boolean weakCompareAndSetIntRelease(Object o, long offset,
1536 int expected,
1537 int x) {
1538 return compareAndSetInt(o, offset, expected, x);
1539 }
1540
1541 @HotSpotIntrinsicCandidate
1542 public final boolean weakCompareAndSetInt(Object o, long offset,
1543 int expected,
1544 int x) {
1545 return compareAndSetInt(o, offset, expected, x);
1546 }
1547
1548 @HotSpotIntrinsicCandidate
1549 public final byte compareAndExchangeByte(Object o, long offset,
1550 byte expected,
1551 byte x) {
1552 long wordOffset = offset & ~3;
1553 int shift = (int) (offset & 3) << 3;
1554 if (BE) {
1555 shift = 24 - shift;
1556 }
1557 int mask = 0xFF << shift;
1558 int maskedExpected = (expected & 0xFF) << shift;
1559 int maskedX = (x & 0xFF) << shift;
1560 int fullWord;
1561 do {
1562 fullWord = getIntVolatile(o, wordOffset);
1563 if ((fullWord & mask) != maskedExpected)
1564 return (byte) ((fullWord & mask) >> shift);
1565 } while (!weakCompareAndSetInt(o, wordOffset,
1566 fullWord, (fullWord & ~mask) | maskedX));
1567 return expected;
1568 }
1569
1570 @HotSpotIntrinsicCandidate
1571 public final boolean compareAndSetByte(Object o, long offset,
1572 byte expected,
1573 byte x) {
1574 return compareAndExchangeByte(o, offset, expected, x) == expected;
1575 }
1576
1577 @HotSpotIntrinsicCandidate
1578 public final boolean weakCompareAndSetByte(Object o, long offset,
1579 byte expected,
1580 byte x) {
1581 return compareAndSetByte(o, offset, expected, x);
1582 }
1583
1584 @HotSpotIntrinsicCandidate
1585 public final boolean weakCompareAndSetByteAcquire(Object o, long offset,
1586 byte expected,
1587 byte x) {
1588 return weakCompareAndSetByte(o, offset, expected, x);
1589 }
1590
1591 @HotSpotIntrinsicCandidate
1592 public final boolean weakCompareAndSetByteRelease(Object o, long offset,
1593 byte expected,
1594 byte x) {
1595 return weakCompareAndSetByte(o, offset, expected, x);
1596 }
1597
1598 @HotSpotIntrinsicCandidate
1599 public final boolean weakCompareAndSetBytePlain(Object o, long offset,
1600 byte expected,
1601 byte x) {
1602 return weakCompareAndSetByte(o, offset, expected, x);
1603 }
1604
1605 @HotSpotIntrinsicCandidate
1606 public final byte compareAndExchangeByteAcquire(Object o, long offset,
1607 byte expected,
1608 byte x) {
1609 return compareAndExchangeByte(o, offset, expected, x);
1610 }
1611
1612 @HotSpotIntrinsicCandidate
1613 public final byte compareAndExchangeByteRelease(Object o, long offset,
1614 byte expected,
1615 byte x) {
1616 return compareAndExchangeByte(o, offset, expected, x);
1617 }
1618
1619 @HotSpotIntrinsicCandidate
1620 public final short compareAndExchangeShort(Object o, long offset,
1621 short expected,
1622 short x) {
1623 if ((offset & 3) == 3) {
1624 throw new IllegalArgumentException("Update spans the word, not supported");
1625 }
1626 long wordOffset = offset & ~3;
1627 int shift = (int) (offset & 3) << 3;
1628 if (BE) {
1629 shift = 16 - shift;
1630 }
1631 int mask = 0xFFFF << shift;
1632 int maskedExpected = (expected & 0xFFFF) << shift;
1633 int maskedX = (x & 0xFFFF) << shift;
1634 int fullWord;
1635 do {
1636 fullWord = getIntVolatile(o, wordOffset);
1637 if ((fullWord & mask) != maskedExpected) {
1638 return (short) ((fullWord & mask) >> shift);
1639 }
1640 } while (!weakCompareAndSetInt(o, wordOffset,
1641 fullWord, (fullWord & ~mask) | maskedX));
1642 return expected;
1643 }
1644
1645 @HotSpotIntrinsicCandidate
1646 public final boolean compareAndSetShort(Object o, long offset,
1647 short expected,
1648 short x) {
1649 return compareAndExchangeShort(o, offset, expected, x) == expected;
1650 }
1651
1652 @HotSpotIntrinsicCandidate
1653 public final boolean weakCompareAndSetShort(Object o, long offset,
1654 short expected,
1655 short x) {
1656 return compareAndSetShort(o, offset, expected, x);
1657 }
1658
1659 @HotSpotIntrinsicCandidate
1660 public final boolean weakCompareAndSetShortAcquire(Object o, long offset,
1661 short expected,
1662 short x) {
1663 return weakCompareAndSetShort(o, offset, expected, x);
1664 }
1665
1666 @HotSpotIntrinsicCandidate
1667 public final boolean weakCompareAndSetShortRelease(Object o, long offset,
1668 short expected,
1669 short x) {
1670 return weakCompareAndSetShort(o, offset, expected, x);
1671 }
1672
1673 @HotSpotIntrinsicCandidate
1674 public final boolean weakCompareAndSetShortPlain(Object o, long offset,
1675 short expected,
1676 short x) {
1677 return weakCompareAndSetShort(o, offset, expected, x);
1678 }
1679
1680
1681 @HotSpotIntrinsicCandidate
1682 public final short compareAndExchangeShortAcquire(Object o, long offset,
1683 short expected,
1684 short x) {
1685 return compareAndExchangeShort(o, offset, expected, x);
1686 }
1687
1688 @HotSpotIntrinsicCandidate
1689 public final short compareAndExchangeShortRelease(Object o, long offset,
1690 short expected,
1691 short x) {
1692 return compareAndExchangeShort(o, offset, expected, x);
1693 }
1694
1695 @ForceInline
1696 private char s2c(short s) {
1697 return (char) s;
1698 }
1699
1700 @ForceInline
1701 private short c2s(char s) {
1702 return (short) s;
1703 }
1704
1705 @ForceInline
1706 public final boolean compareAndSetChar(Object o, long offset,
1707 char expected,
1708 char x) {
1709 return compareAndSetShort(o, offset, c2s(expected), c2s(x));
1710 }
1711
1712 @ForceInline
1713 public final char compareAndExchangeChar(Object o, long offset,
1714 char expected,
1715 char x) {
1716 return s2c(compareAndExchangeShort(o, offset, c2s(expected), c2s(x)));
1717 }
1718
1719 @ForceInline
1720 public final char compareAndExchangeCharAcquire(Object o, long offset,
1721 char expected,
1722 char x) {
1723 return s2c(compareAndExchangeShortAcquire(o, offset, c2s(expected), c2s(x)));
1724 }
1725
1726 @ForceInline
1727 public final char compareAndExchangeCharRelease(Object o, long offset,
1728 char expected,
1729 char x) {
1730 return s2c(compareAndExchangeShortRelease(o, offset, c2s(expected), c2s(x)));
1731 }
1732
1733 @ForceInline
1734 public final boolean weakCompareAndSetChar(Object o, long offset,
1735 char expected,
1736 char x) {
1737 return weakCompareAndSetShort(o, offset, c2s(expected), c2s(x));
1738 }
1739
1740 @ForceInline
1741 public final boolean weakCompareAndSetCharAcquire(Object o, long offset,
1742 char expected,
1743 char x) {
1744 return weakCompareAndSetShortAcquire(o, offset, c2s(expected), c2s(x));
1745 }
1746
1747 @ForceInline
1748 public final boolean weakCompareAndSetCharRelease(Object o, long offset,
1749 char expected,
1750 char x) {
1751 return weakCompareAndSetShortRelease(o, offset, c2s(expected), c2s(x));
1752 }
1753
1754 @ForceInline
1755 public final boolean weakCompareAndSetCharPlain(Object o, long offset,
1756 char expected,
1757 char x) {
1758 return weakCompareAndSetShortPlain(o, offset, c2s(expected), c2s(x));
1759 }
1760
1761 /**
1762 * The JVM converts integral values to boolean values using two
1763 * different conventions, byte testing against zero and truncation
1764 * to least-significant bit.
1765 *
1766 * <p>The JNI documents specify that, at least for returning
1767 * values from native methods, a Java boolean value is converted
1768 * to the value-set 0..1 by first truncating to a byte (0..255 or
1769 * maybe -128..127) and then testing against zero. Thus, Java
1770 * booleans in non-Java data structures are by convention
1771 * represented as 8-bit containers containing either zero (for
1772 * false) or any non-zero value (for true).
1773 *
1774 * <p>Java booleans in the heap are also stored in bytes, but are
1775 * strongly normalized to the value-set 0..1 (i.e., they are
1776 * truncated to the least-significant bit).
1777 *
1778 * <p>The main reason for having different conventions for
1779 * conversion is performance: Truncation to the least-significant
1780 * bit can be usually implemented with fewer (machine)
1781 * instructions than byte testing against zero.
1782 *
1783 * <p>A number of Unsafe methods load boolean values from the heap
1784 * as bytes. Unsafe converts those values according to the JNI
1785 * rules (i.e, using the "testing against zero" convention). The
1786 * method {@code byte2bool} implements that conversion.
1787 *
1788 * @param b the byte to be converted to boolean
1789 * @return the result of the conversion
1790 */
1791 @ForceInline
1792 private boolean byte2bool(byte b) {
1793 return b != 0;
1794 }
1795
1796 /**
1797 * Convert a boolean value to a byte. The return value is strongly
1798 * normalized to the value-set 0..1 (i.e., the value is truncated
1799 * to the least-significant bit). See {@link #byte2bool(byte)} for
1800 * more details on conversion conventions.
1801 *
1802 * @param b the boolean to be converted to byte (and then normalized)
1803 * @return the result of the conversion
1804 */
1805 @ForceInline
1806 private byte bool2byte(boolean b) {
1807 return b ? (byte)1 : (byte)0;
1808 }
1809
1810 @ForceInline
1811 public final boolean compareAndSetBoolean(Object o, long offset,
1812 boolean expected,
1813 boolean x) {
1814 return compareAndSetByte(o, offset, bool2byte(expected), bool2byte(x));
1815 }
1816
1817 @ForceInline
1818 public final boolean compareAndExchangeBoolean(Object o, long offset,
1819 boolean expected,
1820 boolean x) {
1821 return byte2bool(compareAndExchangeByte(o, offset, bool2byte(expected), bool2byte(x)));
1822 }
1823
1824 @ForceInline
1825 public final boolean compareAndExchangeBooleanAcquire(Object o, long offset,
1826 boolean expected,
1827 boolean x) {
1828 return byte2bool(compareAndExchangeByteAcquire(o, offset, bool2byte(expected), bool2byte(x)));
1829 }
1830
1831 @ForceInline
1832 public final boolean compareAndExchangeBooleanRelease(Object o, long offset,
1833 boolean expected,
1834 boolean x) {
1835 return byte2bool(compareAndExchangeByteRelease(o, offset, bool2byte(expected), bool2byte(x)));
1836 }
1837
1838 @ForceInline
1839 public final boolean weakCompareAndSetBoolean(Object o, long offset,
1840 boolean expected,
1841 boolean x) {
1842 return weakCompareAndSetByte(o, offset, bool2byte(expected), bool2byte(x));
1843 }
1844
1845 @ForceInline
1846 public final boolean weakCompareAndSetBooleanAcquire(Object o, long offset,
1847 boolean expected,
1848 boolean x) {
1849 return weakCompareAndSetByteAcquire(o, offset, bool2byte(expected), bool2byte(x));
1850 }
1851
1852 @ForceInline
1853 public final boolean weakCompareAndSetBooleanRelease(Object o, long offset,
1854 boolean expected,
1855 boolean x) {
1856 return weakCompareAndSetByteRelease(o, offset, bool2byte(expected), bool2byte(x));
1857 }
1858
1859 @ForceInline
1860 public final boolean weakCompareAndSetBooleanPlain(Object o, long offset,
1861 boolean expected,
1862 boolean x) {
1863 return weakCompareAndSetBytePlain(o, offset, bool2byte(expected), bool2byte(x));
1864 }
1865
1866 /**
1867 * Atomically updates Java variable to {@code x} if it is currently
1868 * holding {@code expected}.
1869 *
1870 * <p>This operation has memory semantics of a {@code volatile} read
1871 * and write. Corresponds to C11 atomic_compare_exchange_strong.
1872 *
1873 * @return {@code true} if successful
1874 */
1875 @ForceInline
1876 public final boolean compareAndSetFloat(Object o, long offset,
1877 float expected,
1878 float x) {
1879 return compareAndSetInt(o, offset,
1880 Float.floatToRawIntBits(expected),
1881 Float.floatToRawIntBits(x));
1882 }
1883
1884 @ForceInline
1885 public final float compareAndExchangeFloat(Object o, long offset,
1886 float expected,
1887 float x) {
1888 int w = compareAndExchangeInt(o, offset,
1889 Float.floatToRawIntBits(expected),
1890 Float.floatToRawIntBits(x));
1891 return Float.intBitsToFloat(w);
1892 }
1893
1894 @ForceInline
1895 public final float compareAndExchangeFloatAcquire(Object o, long offset,
1896 float expected,
1897 float x) {
1898 int w = compareAndExchangeIntAcquire(o, offset,
1899 Float.floatToRawIntBits(expected),
1900 Float.floatToRawIntBits(x));
1901 return Float.intBitsToFloat(w);
1902 }
1903
1904 @ForceInline
1905 public final float compareAndExchangeFloatRelease(Object o, long offset,
1906 float expected,
1907 float x) {
1908 int w = compareAndExchangeIntRelease(o, offset,
1909 Float.floatToRawIntBits(expected),
1910 Float.floatToRawIntBits(x));
1911 return Float.intBitsToFloat(w);
1912 }
1913
1914 @ForceInline
1915 public final boolean weakCompareAndSetFloatPlain(Object o, long offset,
1916 float expected,
1917 float x) {
1918 return weakCompareAndSetIntPlain(o, offset,
1919 Float.floatToRawIntBits(expected),
1920 Float.floatToRawIntBits(x));
1921 }
1922
1923 @ForceInline
1924 public final boolean weakCompareAndSetFloatAcquire(Object o, long offset,
1925 float expected,
1926 float x) {
1927 return weakCompareAndSetIntAcquire(o, offset,
1928 Float.floatToRawIntBits(expected),
1929 Float.floatToRawIntBits(x));
1930 }
1931
1932 @ForceInline
1933 public final boolean weakCompareAndSetFloatRelease(Object o, long offset,
1934 float expected,
1935 float x) {
1936 return weakCompareAndSetIntRelease(o, offset,
1937 Float.floatToRawIntBits(expected),
1938 Float.floatToRawIntBits(x));
1939 }
1940
1941 @ForceInline
1942 public final boolean weakCompareAndSetFloat(Object o, long offset,
1943 float expected,
1944 float x) {
1945 return weakCompareAndSetInt(o, offset,
1946 Float.floatToRawIntBits(expected),
1947 Float.floatToRawIntBits(x));
1948 }
1949
1950 /**
1951 * Atomically updates Java variable to {@code x} if it is currently
1952 * holding {@code expected}.
1953 *
1954 * <p>This operation has memory semantics of a {@code volatile} read
1955 * and write. Corresponds to C11 atomic_compare_exchange_strong.
1956 *
1957 * @return {@code true} if successful
1958 */
1959 @ForceInline
1960 public final boolean compareAndSetDouble(Object o, long offset,
1961 double expected,
1962 double x) {
1963 return compareAndSetLong(o, offset,
1964 Double.doubleToRawLongBits(expected),
1965 Double.doubleToRawLongBits(x));
1966 }
1967
1968 @ForceInline
1969 public final double compareAndExchangeDouble(Object o, long offset,
1970 double expected,
1971 double x) {
1972 long w = compareAndExchangeLong(o, offset,
1973 Double.doubleToRawLongBits(expected),
1974 Double.doubleToRawLongBits(x));
1975 return Double.longBitsToDouble(w);
1976 }
1977
1978 @ForceInline
1979 public final double compareAndExchangeDoubleAcquire(Object o, long offset,
1980 double expected,
1981 double x) {
1982 long w = compareAndExchangeLongAcquire(o, offset,
1983 Double.doubleToRawLongBits(expected),
1984 Double.doubleToRawLongBits(x));
1985 return Double.longBitsToDouble(w);
1986 }
1987
1988 @ForceInline
1989 public final double compareAndExchangeDoubleRelease(Object o, long offset,
1990 double expected,
1991 double x) {
1992 long w = compareAndExchangeLongRelease(o, offset,
1993 Double.doubleToRawLongBits(expected),
1994 Double.doubleToRawLongBits(x));
1995 return Double.longBitsToDouble(w);
1996 }
1997
1998 @ForceInline
1999 public final boolean weakCompareAndSetDoublePlain(Object o, long offset,
2000 double expected,
2001 double x) {
2002 return weakCompareAndSetLongPlain(o, offset,
2003 Double.doubleToRawLongBits(expected),
2004 Double.doubleToRawLongBits(x));
2005 }
2006
2007 @ForceInline
2008 public final boolean weakCompareAndSetDoubleAcquire(Object o, long offset,
2009 double expected,
2010 double x) {
2011 return weakCompareAndSetLongAcquire(o, offset,
2012 Double.doubleToRawLongBits(expected),
2013 Double.doubleToRawLongBits(x));
2014 }
2015
2016 @ForceInline
2017 public final boolean weakCompareAndSetDoubleRelease(Object o, long offset,
2018 double expected,
2019 double x) {
2020 return weakCompareAndSetLongRelease(o, offset,
2021 Double.doubleToRawLongBits(expected),
2022 Double.doubleToRawLongBits(x));
2023 }
2024
2025 @ForceInline
2026 public final boolean weakCompareAndSetDouble(Object o, long offset,
2027 double expected,
2028 double x) {
2029 return weakCompareAndSetLong(o, offset,
2030 Double.doubleToRawLongBits(expected),
2031 Double.doubleToRawLongBits(x));
2032 }
2033
2034 /**
2035 * Atomically updates Java variable to {@code x} if it is currently
2036 * holding {@code expected}.
2037 *
2038 * <p>This operation has memory semantics of a {@code volatile} read
2039 * and write. Corresponds to C11 atomic_compare_exchange_strong.
2040 *
2041 * @return {@code true} if successful
2042 */
2043 @HotSpotIntrinsicCandidate
2044 public final native boolean compareAndSetLong(Object o, long offset,
2045 long expected,
2046 long x);
2047
2048 @HotSpotIntrinsicCandidate
2049 public final native long compareAndExchangeLong(Object o, long offset,
2050 long expected,
2051 long x);
2052
2053 @HotSpotIntrinsicCandidate
2054 public final long compareAndExchangeLongAcquire(Object o, long offset,
2055 long expected,
2056 long x) {
2057 return compareAndExchangeLong(o, offset, expected, x);
2058 }
2059
2060 @HotSpotIntrinsicCandidate
2061 public final long compareAndExchangeLongRelease(Object o, long offset,
2062 long expected,
2063 long x) {
2064 return compareAndExchangeLong(o, offset, expected, x);
2065 }
2066
2067 @HotSpotIntrinsicCandidate
2068 public final boolean weakCompareAndSetLongPlain(Object o, long offset,
2069 long expected,
2070 long x) {
2071 return compareAndSetLong(o, offset, expected, x);
2072 }
2073
2074 @HotSpotIntrinsicCandidate
2075 public final boolean weakCompareAndSetLongAcquire(Object o, long offset,
2076 long expected,
2077 long x) {
2078 return compareAndSetLong(o, offset, expected, x);
2079 }
2080
2081 @HotSpotIntrinsicCandidate
2082 public final boolean weakCompareAndSetLongRelease(Object o, long offset,
2083 long expected,
2084 long x) {
2085 return compareAndSetLong(o, offset, expected, x);
2086 }
2087
2088 @HotSpotIntrinsicCandidate
2089 public final boolean weakCompareAndSetLong(Object o, long offset,
2090 long expected,
2091 long x) {
2092 return compareAndSetLong(o, offset, expected, x);
2093 }
2094
2095 /**
2096 * Fetches a reference value from a given Java variable, with volatile
2097 * load semantics. Otherwise identical to {@link #getReference(Object, long)}
2098 */
2099 @HotSpotIntrinsicCandidate
2100 public native Object getReferenceVolatile(Object o, long offset);
2101
2102 /**
2103 * Global lock for atomic and volatile strength access to any value of
2104 * a value type. This is a temporary workaround until better localized
2105 * atomic access mechanisms are supported for value types.
2106 */
2107 private static final Object valueLock = new Object();
2108
2109 public final <V> Object getValueVolatile(Object base, long offset, Class<?> valueType) {
2110 synchronized (valueLock) {
2111 return getValue(base, offset, valueType);
2112 }
2113 }
2114
2115 /**
2116 * Stores a reference value into a given Java variable, with
2117 * volatile store semantics. Otherwise identical to {@link #putReference(Object, long, Object)}
2118 */
2119 @HotSpotIntrinsicCandidate
2120 public native void putReferenceVolatile(Object o, long offset, Object x);
2121
2122 public final <V> void putValueVolatile(Object o, long offset, Class<?> valueType, V x) {
2123 synchronized (valueLock) {
2124 putValue(o, offset, valueType, x);
2125 }
2126 }
2127
2128 /** Volatile version of {@link #getInt(Object, long)} */
2129 @HotSpotIntrinsicCandidate
2130 public native int getIntVolatile(Object o, long offset);
2131
2132 /** Volatile version of {@link #putInt(Object, long, int)} */
2133 @HotSpotIntrinsicCandidate
2134 public native void putIntVolatile(Object o, long offset, int x);
2135
2136 /** Volatile version of {@link #getBoolean(Object, long)} */
2137 @HotSpotIntrinsicCandidate
2138 public native boolean getBooleanVolatile(Object o, long offset);
2139
2140 /** Volatile version of {@link #putBoolean(Object, long, boolean)} */
2141 @HotSpotIntrinsicCandidate
2142 public native void putBooleanVolatile(Object o, long offset, boolean x);
2143
2144 /** Volatile version of {@link #getByte(Object, long)} */
2145 @HotSpotIntrinsicCandidate
2146 public native byte getByteVolatile(Object o, long offset);
2147
2148 /** Volatile version of {@link #putByte(Object, long, byte)} */
2149 @HotSpotIntrinsicCandidate
2150 public native void putByteVolatile(Object o, long offset, byte x);
2151
2152 /** Volatile version of {@link #getShort(Object, long)} */
2153 @HotSpotIntrinsicCandidate
2154 public native short getShortVolatile(Object o, long offset);
2155
2156 /** Volatile version of {@link #putShort(Object, long, short)} */
2157 @HotSpotIntrinsicCandidate
2158 public native void putShortVolatile(Object o, long offset, short x);
2159
2160 /** Volatile version of {@link #getChar(Object, long)} */
2161 @HotSpotIntrinsicCandidate
2162 public native char getCharVolatile(Object o, long offset);
2163
2164 /** Volatile version of {@link #putChar(Object, long, char)} */
2165 @HotSpotIntrinsicCandidate
2166 public native void putCharVolatile(Object o, long offset, char x);
2167
2168 /** Volatile version of {@link #getLong(Object, long)} */
2169 @HotSpotIntrinsicCandidate
2170 public native long getLongVolatile(Object o, long offset);
2171
2172 /** Volatile version of {@link #putLong(Object, long, long)} */
2173 @HotSpotIntrinsicCandidate
2174 public native void putLongVolatile(Object o, long offset, long x);
2175
2176 /** Volatile version of {@link #getFloat(Object, long)} */
2177 @HotSpotIntrinsicCandidate
2178 public native float getFloatVolatile(Object o, long offset);
2179
2180 /** Volatile version of {@link #putFloat(Object, long, float)} */
2181 @HotSpotIntrinsicCandidate
2182 public native void putFloatVolatile(Object o, long offset, float x);
2183
2184 /** Volatile version of {@link #getDouble(Object, long)} */
2185 @HotSpotIntrinsicCandidate
2186 public native double getDoubleVolatile(Object o, long offset);
2187
2188 /** Volatile version of {@link #putDouble(Object, long, double)} */
2189 @HotSpotIntrinsicCandidate
2190 public native void putDoubleVolatile(Object o, long offset, double x);
2191
2192
2193
2194 /** Acquire version of {@link #getReferenceVolatile(Object, long)} */
2195 @HotSpotIntrinsicCandidate
2196 public final Object getReferenceAcquire(Object o, long offset) {
2197 return getReferenceVolatile(o, offset);
2198 }
2199
2200 public final <V> Object getValueAcquire(Object base, long offset, Class<?> valueType) {
2201 return getValueVolatile(base, offset, valueType);
2202 }
2203
2204 /** Acquire version of {@link #getBooleanVolatile(Object, long)} */
2205 @HotSpotIntrinsicCandidate
2206 public final boolean getBooleanAcquire(Object o, long offset) {
2207 return getBooleanVolatile(o, offset);
2208 }
2209
2210 /** Acquire version of {@link #getByteVolatile(Object, long)} */
2211 @HotSpotIntrinsicCandidate
2212 public final byte getByteAcquire(Object o, long offset) {
2213 return getByteVolatile(o, offset);
2214 }
2215
2216 /** Acquire version of {@link #getShortVolatile(Object, long)} */
2217 @HotSpotIntrinsicCandidate
2218 public final short getShortAcquire(Object o, long offset) {
2219 return getShortVolatile(o, offset);
2220 }
2221
2222 /** Acquire version of {@link #getCharVolatile(Object, long)} */
2223 @HotSpotIntrinsicCandidate
2224 public final char getCharAcquire(Object o, long offset) {
2225 return getCharVolatile(o, offset);
2226 }
2227
2228 /** Acquire version of {@link #getIntVolatile(Object, long)} */
2229 @HotSpotIntrinsicCandidate
2230 public final int getIntAcquire(Object o, long offset) {
2231 return getIntVolatile(o, offset);
2232 }
2233
2234 /** Acquire version of {@link #getFloatVolatile(Object, long)} */
2235 @HotSpotIntrinsicCandidate
2236 public final float getFloatAcquire(Object o, long offset) {
2237 return getFloatVolatile(o, offset);
2238 }
2239
2240 /** Acquire version of {@link #getLongVolatile(Object, long)} */
2241 @HotSpotIntrinsicCandidate
2242 public final long getLongAcquire(Object o, long offset) {
2243 return getLongVolatile(o, offset);
2244 }
2245
2246 /** Acquire version of {@link #getDoubleVolatile(Object, long)} */
2247 @HotSpotIntrinsicCandidate
2248 public final double getDoubleAcquire(Object o, long offset) {
2249 return getDoubleVolatile(o, offset);
2250 }
2251
2252 /*
2253 * Versions of {@link #putReferenceVolatile(Object, long, Object)}
2254 * that do not guarantee immediate visibility of the store to
2255 * other threads. This method is generally only useful if the
2256 * underlying field is a Java volatile (or if an array cell, one
2257 * that is otherwise only accessed using volatile accesses).
2258 *
2259 * Corresponds to C11 atomic_store_explicit(..., memory_order_release).
2260 */
2261
2262 /** Release version of {@link #putReferenceVolatile(Object, long, Object)} */
2263 @HotSpotIntrinsicCandidate
2264 public final void putReferenceRelease(Object o, long offset, Object x) {
2265 putReferenceVolatile(o, offset, x);
2266 }
2267
2268 public final <V> void putValueRelease(Object o, long offset, Class<?> valueType, V x) {
2269 putValueVolatile(o, offset, valueType, x);
2270 }
2271
2272 /** Release version of {@link #putBooleanVolatile(Object, long, boolean)} */
2273 @HotSpotIntrinsicCandidate
2274 public final void putBooleanRelease(Object o, long offset, boolean x) {
2275 putBooleanVolatile(o, offset, x);
2276 }
2277
2278 /** Release version of {@link #putByteVolatile(Object, long, byte)} */
2279 @HotSpotIntrinsicCandidate
2280 public final void putByteRelease(Object o, long offset, byte x) {
2281 putByteVolatile(o, offset, x);
2282 }
2283
2284 /** Release version of {@link #putShortVolatile(Object, long, short)} */
2285 @HotSpotIntrinsicCandidate
2286 public final void putShortRelease(Object o, long offset, short x) {
2287 putShortVolatile(o, offset, x);
2288 }
2289
2290 /** Release version of {@link #putCharVolatile(Object, long, char)} */
2291 @HotSpotIntrinsicCandidate
2292 public final void putCharRelease(Object o, long offset, char x) {
2293 putCharVolatile(o, offset, x);
2294 }
2295
2296 /** Release version of {@link #putIntVolatile(Object, long, int)} */
2297 @HotSpotIntrinsicCandidate
2298 public final void putIntRelease(Object o, long offset, int x) {
2299 putIntVolatile(o, offset, x);
2300 }
2301
2302 /** Release version of {@link #putFloatVolatile(Object, long, float)} */
2303 @HotSpotIntrinsicCandidate
2304 public final void putFloatRelease(Object o, long offset, float x) {
2305 putFloatVolatile(o, offset, x);
2306 }
2307
2308 /** Release version of {@link #putLongVolatile(Object, long, long)} */
2309 @HotSpotIntrinsicCandidate
2310 public final void putLongRelease(Object o, long offset, long x) {
2311 putLongVolatile(o, offset, x);
2312 }
2313
2314 /** Release version of {@link #putDoubleVolatile(Object, long, double)} */
2315 @HotSpotIntrinsicCandidate
2316 public final void putDoubleRelease(Object o, long offset, double x) {
2317 putDoubleVolatile(o, offset, x);
2318 }
2319
2320 // ------------------------------ Opaque --------------------------------------
2321
2322 /** Opaque version of {@link #getReferenceVolatile(Object, long)} */
2323 @HotSpotIntrinsicCandidate
2324 public final Object getReferenceOpaque(Object o, long offset) {
2325 return getReferenceVolatile(o, offset);
2326 }
2327
2328 public final <V> Object getValueOpaque(Object base, long offset, Class<?> valueType) {
2329 return getValueVolatile(base, offset, valueType);
2330 }
2331
2332 /** Opaque version of {@link #getBooleanVolatile(Object, long)} */
2333 @HotSpotIntrinsicCandidate
2334 public final boolean getBooleanOpaque(Object o, long offset) {
2335 return getBooleanVolatile(o, offset);
2336 }
2337
2338 /** Opaque version of {@link #getByteVolatile(Object, long)} */
2339 @HotSpotIntrinsicCandidate
2340 public final byte getByteOpaque(Object o, long offset) {
2341 return getByteVolatile(o, offset);
2342 }
2343
2344 /** Opaque version of {@link #getShortVolatile(Object, long)} */
2345 @HotSpotIntrinsicCandidate
2346 public final short getShortOpaque(Object o, long offset) {
2347 return getShortVolatile(o, offset);
2348 }
2349
2350 /** Opaque version of {@link #getCharVolatile(Object, long)} */
2351 @HotSpotIntrinsicCandidate
2352 public final char getCharOpaque(Object o, long offset) {
2353 return getCharVolatile(o, offset);
2354 }
2355
2356 /** Opaque version of {@link #getIntVolatile(Object, long)} */
2357 @HotSpotIntrinsicCandidate
2358 public final int getIntOpaque(Object o, long offset) {
2359 return getIntVolatile(o, offset);
2360 }
2361
2362 /** Opaque version of {@link #getFloatVolatile(Object, long)} */
2363 @HotSpotIntrinsicCandidate
2364 public final float getFloatOpaque(Object o, long offset) {
2365 return getFloatVolatile(o, offset);
2366 }
2367
2368 /** Opaque version of {@link #getLongVolatile(Object, long)} */
2369 @HotSpotIntrinsicCandidate
2370 public final long getLongOpaque(Object o, long offset) {
2371 return getLongVolatile(o, offset);
2372 }
2373
2374 /** Opaque version of {@link #getDoubleVolatile(Object, long)} */
2375 @HotSpotIntrinsicCandidate
2376 public final double getDoubleOpaque(Object o, long offset) {
2377 return getDoubleVolatile(o, offset);
2378 }
2379
2380 /** Opaque version of {@link #putReferenceVolatile(Object, long, Object)} */
2381 @HotSpotIntrinsicCandidate
2382 public final void putReferenceOpaque(Object o, long offset, Object x) {
2383 putReferenceVolatile(o, offset, x);
2384 }
2385
2386 public final <V> void putValueOpaque(Object o, long offset, Class<?> valueType, V x) {
2387 putValueVolatile(o, offset, valueType, x);
2388 }
2389
2390 /** Opaque version of {@link #putBooleanVolatile(Object, long, boolean)} */
2391 @HotSpotIntrinsicCandidate
2392 public final void putBooleanOpaque(Object o, long offset, boolean x) {
2393 putBooleanVolatile(o, offset, x);
2394 }
2395
2396 /** Opaque version of {@link #putByteVolatile(Object, long, byte)} */
2397 @HotSpotIntrinsicCandidate
2398 public final void putByteOpaque(Object o, long offset, byte x) {
2399 putByteVolatile(o, offset, x);
2400 }
2401
2402 /** Opaque version of {@link #putShortVolatile(Object, long, short)} */
2403 @HotSpotIntrinsicCandidate
2404 public final void putShortOpaque(Object o, long offset, short x) {
2405 putShortVolatile(o, offset, x);
2406 }
2407
2408 /** Opaque version of {@link #putCharVolatile(Object, long, char)} */
2409 @HotSpotIntrinsicCandidate
2410 public final void putCharOpaque(Object o, long offset, char x) {
2411 putCharVolatile(o, offset, x);
2412 }
2413
2414 /** Opaque version of {@link #putIntVolatile(Object, long, int)} */
2415 @HotSpotIntrinsicCandidate
2416 public final void putIntOpaque(Object o, long offset, int x) {
2417 putIntVolatile(o, offset, x);
2418 }
2419
2420 /** Opaque version of {@link #putFloatVolatile(Object, long, float)} */
2421 @HotSpotIntrinsicCandidate
2422 public final void putFloatOpaque(Object o, long offset, float x) {
2423 putFloatVolatile(o, offset, x);
2424 }
2425
2426 /** Opaque version of {@link #putLongVolatile(Object, long, long)} */
2427 @HotSpotIntrinsicCandidate
2428 public final void putLongOpaque(Object o, long offset, long x) {
2429 putLongVolatile(o, offset, x);
2430 }
2431
2432 /** Opaque version of {@link #putDoubleVolatile(Object, long, double)} */
2433 @HotSpotIntrinsicCandidate
2434 public final void putDoubleOpaque(Object o, long offset, double x) {
2435 putDoubleVolatile(o, offset, x);
2436 }
2437
2438 /**
2439 * Unblocks the given thread blocked on {@code park}, or, if it is
2440 * not blocked, causes the subsequent call to {@code park} not to
2441 * block. Note: this operation is "unsafe" solely because the
2442 * caller must somehow ensure that the thread has not been
2443 * destroyed. Nothing special is usually required to ensure this
2444 * when called from Java (in which there will ordinarily be a live
2445 * reference to the thread) but this is not nearly-automatically
2446 * so when calling from native code.
2447 *
2448 * @param thread the thread to unpark.
2449 */
2450 @HotSpotIntrinsicCandidate
2451 public native void unpark(Object thread);
2452
2453 /**
2454 * Blocks current thread, returning when a balancing
2455 * {@code unpark} occurs, or a balancing {@code unpark} has
2456 * already occurred, or the thread is interrupted, or, if not
2457 * absolute and time is not zero, the given time nanoseconds have
2458 * elapsed, or if absolute, the given deadline in milliseconds
2459 * since Epoch has passed, or spuriously (i.e., returning for no
2460 * "reason"). Note: This operation is in the Unsafe class only
2461 * because {@code unpark} is, so it would be strange to place it
2462 * elsewhere.
2463 */
2464 @HotSpotIntrinsicCandidate
2465 public native void park(boolean isAbsolute, long time);
2466
2467 /**
2468 * Gets the load average in the system run queue assigned
2469 * to the available processors averaged over various periods of time.
2470 * This method retrieves the given {@code nelem} samples and
2471 * assigns to the elements of the given {@code loadavg} array.
2472 * The system imposes a maximum of 3 samples, representing
2473 * averages over the last 1, 5, and 15 minutes, respectively.
2474 *
2475 * @param loadavg an array of double of size nelems
2476 * @param nelems the number of samples to be retrieved and
2477 * must be 1 to 3.
2478 *
2479 * @return the number of samples actually retrieved; or -1
2480 * if the load average is unobtainable.
2481 */
2482 public int getLoadAverage(double[] loadavg, int nelems) {
2483 if (nelems < 0 || nelems > 3 || nelems > loadavg.length) {
2484 throw new ArrayIndexOutOfBoundsException();
2485 }
2486
2487 return getLoadAverage0(loadavg, nelems);
2488 }
2489
2490 // The following contain CAS-based Java implementations used on
2491 // platforms not supporting native instructions
2492
2493 /**
2494 * Atomically adds the given value to the current value of a field
2495 * or array element within the given object {@code o}
2496 * at the given {@code offset}.
2497 *
2498 * @param o object/array to update the field/element in
2499 * @param offset field/element offset
2500 * @param delta the value to add
2501 * @return the previous value
2502 * @since 1.8
2503 */
2504 @HotSpotIntrinsicCandidate
2505 public final int getAndAddInt(Object o, long offset, int delta) {
2506 int v;
2507 do {
2508 v = getIntVolatile(o, offset);
2509 } while (!weakCompareAndSetInt(o, offset, v, v + delta));
2510 return v;
2511 }
2512
2513 @ForceInline
2514 public final int getAndAddIntRelease(Object o, long offset, int delta) {
2515 int v;
2516 do {
2517 v = getInt(o, offset);
2518 } while (!weakCompareAndSetIntRelease(o, offset, v, v + delta));
2519 return v;
2520 }
2521
2522 @ForceInline
2523 public final int getAndAddIntAcquire(Object o, long offset, int delta) {
2524 int v;
2525 do {
2526 v = getIntAcquire(o, offset);
2527 } while (!weakCompareAndSetIntAcquire(o, offset, v, v + delta));
2528 return v;
2529 }
2530
2531 /**
2532 * Atomically adds the given value to the current value of a field
2533 * or array element within the given object {@code o}
2534 * at the given {@code offset}.
2535 *
2536 * @param o object/array to update the field/element in
2537 * @param offset field/element offset
2538 * @param delta the value to add
2539 * @return the previous value
2540 * @since 1.8
2541 */
2542 @HotSpotIntrinsicCandidate
2543 public final long getAndAddLong(Object o, long offset, long delta) {
2544 long v;
2545 do {
2546 v = getLongVolatile(o, offset);
2547 } while (!weakCompareAndSetLong(o, offset, v, v + delta));
2548 return v;
2549 }
2550
2551 @ForceInline
2552 public final long getAndAddLongRelease(Object o, long offset, long delta) {
2553 long v;
2554 do {
2555 v = getLong(o, offset);
2556 } while (!weakCompareAndSetLongRelease(o, offset, v, v + delta));
2557 return v;
2558 }
2559
2560 @ForceInline
2561 public final long getAndAddLongAcquire(Object o, long offset, long delta) {
2562 long v;
2563 do {
2564 v = getLongAcquire(o, offset);
2565 } while (!weakCompareAndSetLongAcquire(o, offset, v, v + delta));
2566 return v;
2567 }
2568
2569 @HotSpotIntrinsicCandidate
2570 public final byte getAndAddByte(Object o, long offset, byte delta) {
2571 byte v;
2572 do {
2573 v = getByteVolatile(o, offset);
2574 } while (!weakCompareAndSetByte(o, offset, v, (byte) (v + delta)));
2575 return v;
2576 }
2577
2578 @ForceInline
2579 public final byte getAndAddByteRelease(Object o, long offset, byte delta) {
2580 byte v;
2581 do {
2582 v = getByte(o, offset);
2583 } while (!weakCompareAndSetByteRelease(o, offset, v, (byte) (v + delta)));
2584 return v;
2585 }
2586
2587 @ForceInline
2588 public final byte getAndAddByteAcquire(Object o, long offset, byte delta) {
2589 byte v;
2590 do {
2591 v = getByteAcquire(o, offset);
2592 } while (!weakCompareAndSetByteAcquire(o, offset, v, (byte) (v + delta)));
2593 return v;
2594 }
2595
2596 @HotSpotIntrinsicCandidate
2597 public final short getAndAddShort(Object o, long offset, short delta) {
2598 short v;
2599 do {
2600 v = getShortVolatile(o, offset);
2601 } while (!weakCompareAndSetShort(o, offset, v, (short) (v + delta)));
2602 return v;
2603 }
2604
2605 @ForceInline
2606 public final short getAndAddShortRelease(Object o, long offset, short delta) {
2607 short v;
2608 do {
2609 v = getShort(o, offset);
2610 } while (!weakCompareAndSetShortRelease(o, offset, v, (short) (v + delta)));
2611 return v;
2612 }
2613
2614 @ForceInline
2615 public final short getAndAddShortAcquire(Object o, long offset, short delta) {
2616 short v;
2617 do {
2618 v = getShortAcquire(o, offset);
2619 } while (!weakCompareAndSetShortAcquire(o, offset, v, (short) (v + delta)));
2620 return v;
2621 }
2622
2623 @ForceInline
2624 public final char getAndAddChar(Object o, long offset, char delta) {
2625 return (char) getAndAddShort(o, offset, (short) delta);
2626 }
2627
2628 @ForceInline
2629 public final char getAndAddCharRelease(Object o, long offset, char delta) {
2630 return (char) getAndAddShortRelease(o, offset, (short) delta);
2631 }
2632
2633 @ForceInline
2634 public final char getAndAddCharAcquire(Object o, long offset, char delta) {
2635 return (char) getAndAddShortAcquire(o, offset, (short) delta);
2636 }
2637
2638 @ForceInline
2639 public final float getAndAddFloat(Object o, long offset, float delta) {
2640 int expectedBits;
2641 float v;
2642 do {
2643 // Load and CAS with the raw bits to avoid issues with NaNs and
2644 // possible bit conversion from signaling NaNs to quiet NaNs that
2645 // may result in the loop not terminating.
2646 expectedBits = getIntVolatile(o, offset);
2647 v = Float.intBitsToFloat(expectedBits);
2648 } while (!weakCompareAndSetInt(o, offset,
2649 expectedBits, Float.floatToRawIntBits(v + delta)));
2650 return v;
2651 }
2652
2653 @ForceInline
2654 public final float getAndAddFloatRelease(Object o, long offset, float delta) {
2655 int expectedBits;
2656 float v;
2657 do {
2658 // Load and CAS with the raw bits to avoid issues with NaNs and
2659 // possible bit conversion from signaling NaNs to quiet NaNs that
2660 // may result in the loop not terminating.
2661 expectedBits = getInt(o, offset);
2662 v = Float.intBitsToFloat(expectedBits);
2663 } while (!weakCompareAndSetIntRelease(o, offset,
2664 expectedBits, Float.floatToRawIntBits(v + delta)));
2665 return v;
2666 }
2667
2668 @ForceInline
2669 public final float getAndAddFloatAcquire(Object o, long offset, float delta) {
2670 int expectedBits;
2671 float v;
2672 do {
2673 // Load and CAS with the raw bits to avoid issues with NaNs and
2674 // possible bit conversion from signaling NaNs to quiet NaNs that
2675 // may result in the loop not terminating.
2676 expectedBits = getIntAcquire(o, offset);
2677 v = Float.intBitsToFloat(expectedBits);
2678 } while (!weakCompareAndSetIntAcquire(o, offset,
2679 expectedBits, Float.floatToRawIntBits(v + delta)));
2680 return v;
2681 }
2682
2683 @ForceInline
2684 public final double getAndAddDouble(Object o, long offset, double delta) {
2685 long expectedBits;
2686 double v;
2687 do {
2688 // Load and CAS with the raw bits to avoid issues with NaNs and
2689 // possible bit conversion from signaling NaNs to quiet NaNs that
2690 // may result in the loop not terminating.
2691 expectedBits = getLongVolatile(o, offset);
2692 v = Double.longBitsToDouble(expectedBits);
2693 } while (!weakCompareAndSetLong(o, offset,
2694 expectedBits, Double.doubleToRawLongBits(v + delta)));
2695 return v;
2696 }
2697
2698 @ForceInline
2699 public final double getAndAddDoubleRelease(Object o, long offset, double delta) {
2700 long expectedBits;
2701 double v;
2702 do {
2703 // Load and CAS with the raw bits to avoid issues with NaNs and
2704 // possible bit conversion from signaling NaNs to quiet NaNs that
2705 // may result in the loop not terminating.
2706 expectedBits = getLong(o, offset);
2707 v = Double.longBitsToDouble(expectedBits);
2708 } while (!weakCompareAndSetLongRelease(o, offset,
2709 expectedBits, Double.doubleToRawLongBits(v + delta)));
2710 return v;
2711 }
2712
2713 @ForceInline
2714 public final double getAndAddDoubleAcquire(Object o, long offset, double delta) {
2715 long expectedBits;
2716 double v;
2717 do {
2718 // Load and CAS with the raw bits to avoid issues with NaNs and
2719 // possible bit conversion from signaling NaNs to quiet NaNs that
2720 // may result in the loop not terminating.
2721 expectedBits = getLongAcquire(o, offset);
2722 v = Double.longBitsToDouble(expectedBits);
2723 } while (!weakCompareAndSetLongAcquire(o, offset,
2724 expectedBits, Double.doubleToRawLongBits(v + delta)));
2725 return v;
2726 }
2727
2728 /**
2729 * Atomically exchanges the given value with the current value of
2730 * a field or array element within the given object {@code o}
2731 * at the given {@code offset}.
2732 *
2733 * @param o object/array to update the field/element in
2734 * @param offset field/element offset
2735 * @param newValue new value
2736 * @return the previous value
2737 * @since 1.8
2738 */
2739 @HotSpotIntrinsicCandidate
2740 public final int getAndSetInt(Object o, long offset, int newValue) {
2741 int v;
2742 do {
2743 v = getIntVolatile(o, offset);
2744 } while (!weakCompareAndSetInt(o, offset, v, newValue));
2745 return v;
2746 }
2747
2748 @ForceInline
2749 public final int getAndSetIntRelease(Object o, long offset, int newValue) {
2750 int v;
2751 do {
2752 v = getInt(o, offset);
2753 } while (!weakCompareAndSetIntRelease(o, offset, v, newValue));
2754 return v;
2755 }
2756
2757 @ForceInline
2758 public final int getAndSetIntAcquire(Object o, long offset, int newValue) {
2759 int v;
2760 do {
2761 v = getIntAcquire(o, offset);
2762 } while (!weakCompareAndSetIntAcquire(o, offset, v, newValue));
2763 return v;
2764 }
2765
2766 /**
2767 * Atomically exchanges the given value with the current value of
2768 * a field or array element within the given object {@code o}
2769 * at the given {@code offset}.
2770 *
2771 * @param o object/array to update the field/element in
2772 * @param offset field/element offset
2773 * @param newValue new value
2774 * @return the previous value
2775 * @since 1.8
2776 */
2777 @HotSpotIntrinsicCandidate
2778 public final long getAndSetLong(Object o, long offset, long newValue) {
2779 long v;
2780 do {
2781 v = getLongVolatile(o, offset);
2782 } while (!weakCompareAndSetLong(o, offset, v, newValue));
2783 return v;
2784 }
2785
2786 @ForceInline
2787 public final long getAndSetLongRelease(Object o, long offset, long newValue) {
2788 long v;
2789 do {
2790 v = getLong(o, offset);
2791 } while (!weakCompareAndSetLongRelease(o, offset, v, newValue));
2792 return v;
2793 }
2794
2795 @ForceInline
2796 public final long getAndSetLongAcquire(Object o, long offset, long newValue) {
2797 long v;
2798 do {
2799 v = getLongAcquire(o, offset);
2800 } while (!weakCompareAndSetLongAcquire(o, offset, v, newValue));
2801 return v;
2802 }
2803
2804 /**
2805 * Atomically exchanges the given reference value with the current
2806 * reference value of a field or array element within the given
2807 * object {@code o} at the given {@code offset}.
2808 *
2809 * @param o object/array to update the field/element in
2810 * @param offset field/element offset
2811 * @param newValue new value
2812 * @return the previous value
2813 * @since 1.8
2814 */
2815 @HotSpotIntrinsicCandidate
2816 public final Object getAndSetReference(Object o, long offset, Object newValue) {
2817 Object v;
2818 do {
2819 v = getReferenceVolatile(o, offset);
2820 } while (!weakCompareAndSetReference(o, offset, v, newValue));
2821 return v;
2822 }
2823
2824 @SuppressWarnings("unchecked")
2825 public final <V> Object getAndSetValue(Object o, long offset, Class<?> valueType, V newValue) {
2826 synchronized (valueLock) {
2827 Object oldValue = getValue(o, offset, valueType);
2828 putValue(o, offset, valueType, newValue);
2829 return oldValue;
2830 }
2831 }
2832
2833 @ForceInline
2834 public final Object getAndSetReferenceRelease(Object o, long offset, Object newValue) {
2835 Object v;
2836 do {
2837 v = getReference(o, offset);
2838 } while (!weakCompareAndSetReferenceRelease(o, offset, v, newValue));
2839 return v;
2840 }
2841
2842 @ForceInline
2843 public final <V> Object getAndSetValueRelease(Object o, long offset, Class<?> valueType, V newValue) {
2844 return getAndSetValue(o, offset, valueType, newValue);
2845 }
2846
2847 @ForceInline
2848 public final Object getAndSetReferenceAcquire(Object o, long offset, Object newValue) {
2849 Object v;
2850 do {
2851 v = getReferenceAcquire(o, offset);
2852 } while (!weakCompareAndSetReferenceAcquire(o, offset, v, newValue));
2853 return v;
2854 }
2855
2856 @ForceInline
2857 public final <V> Object getAndSetValueAcquire(Object o, long offset, Class<?> valueType, V newValue) {
2858 return getAndSetValue(o, offset, valueType, newValue);
2859 }
2860
2861 @HotSpotIntrinsicCandidate
2862 public final byte getAndSetByte(Object o, long offset, byte newValue) {
2863 byte v;
2864 do {
2865 v = getByteVolatile(o, offset);
2866 } while (!weakCompareAndSetByte(o, offset, v, newValue));
2867 return v;
2868 }
2869
2870 @ForceInline
2871 public final byte getAndSetByteRelease(Object o, long offset, byte newValue) {
2872 byte v;
2873 do {
2874 v = getByte(o, offset);
2875 } while (!weakCompareAndSetByteRelease(o, offset, v, newValue));
2876 return v;
2877 }
2878
2879 @ForceInline
2880 public final byte getAndSetByteAcquire(Object o, long offset, byte newValue) {
2881 byte v;
2882 do {
2883 v = getByteAcquire(o, offset);
2884 } while (!weakCompareAndSetByteAcquire(o, offset, v, newValue));
2885 return v;
2886 }
2887
2888 @ForceInline
2889 public final boolean getAndSetBoolean(Object o, long offset, boolean newValue) {
2890 return byte2bool(getAndSetByte(o, offset, bool2byte(newValue)));
2891 }
2892
2893 @ForceInline
2894 public final boolean getAndSetBooleanRelease(Object o, long offset, boolean newValue) {
2895 return byte2bool(getAndSetByteRelease(o, offset, bool2byte(newValue)));
2896 }
2897
2898 @ForceInline
2899 public final boolean getAndSetBooleanAcquire(Object o, long offset, boolean newValue) {
2900 return byte2bool(getAndSetByteAcquire(o, offset, bool2byte(newValue)));
2901 }
2902
2903 @HotSpotIntrinsicCandidate
2904 public final short getAndSetShort(Object o, long offset, short newValue) {
2905 short v;
2906 do {
2907 v = getShortVolatile(o, offset);
2908 } while (!weakCompareAndSetShort(o, offset, v, newValue));
2909 return v;
2910 }
2911
2912 @ForceInline
2913 public final short getAndSetShortRelease(Object o, long offset, short newValue) {
2914 short v;
2915 do {
2916 v = getShort(o, offset);
2917 } while (!weakCompareAndSetShortRelease(o, offset, v, newValue));
2918 return v;
2919 }
2920
2921 @ForceInline
2922 public final short getAndSetShortAcquire(Object o, long offset, short newValue) {
2923 short v;
2924 do {
2925 v = getShortAcquire(o, offset);
2926 } while (!weakCompareAndSetShortAcquire(o, offset, v, newValue));
2927 return v;
2928 }
2929
2930 @ForceInline
2931 public final char getAndSetChar(Object o, long offset, char newValue) {
2932 return s2c(getAndSetShort(o, offset, c2s(newValue)));
2933 }
2934
2935 @ForceInline
2936 public final char getAndSetCharRelease(Object o, long offset, char newValue) {
2937 return s2c(getAndSetShortRelease(o, offset, c2s(newValue)));
2938 }
2939
2940 @ForceInline
2941 public final char getAndSetCharAcquire(Object o, long offset, char newValue) {
2942 return s2c(getAndSetShortAcquire(o, offset, c2s(newValue)));
2943 }
2944
2945 @ForceInline
2946 public final float getAndSetFloat(Object o, long offset, float newValue) {
2947 int v = getAndSetInt(o, offset, Float.floatToRawIntBits(newValue));
2948 return Float.intBitsToFloat(v);
2949 }
2950
2951 @ForceInline
2952 public final float getAndSetFloatRelease(Object o, long offset, float newValue) {
2953 int v = getAndSetIntRelease(o, offset, Float.floatToRawIntBits(newValue));
2954 return Float.intBitsToFloat(v);
2955 }
2956
2957 @ForceInline
2958 public final float getAndSetFloatAcquire(Object o, long offset, float newValue) {
2959 int v = getAndSetIntAcquire(o, offset, Float.floatToRawIntBits(newValue));
2960 return Float.intBitsToFloat(v);
2961 }
2962
2963 @ForceInline
2964 public final double getAndSetDouble(Object o, long offset, double newValue) {
2965 long v = getAndSetLong(o, offset, Double.doubleToRawLongBits(newValue));
2966 return Double.longBitsToDouble(v);
2967 }
2968
2969 @ForceInline
2970 public final double getAndSetDoubleRelease(Object o, long offset, double newValue) {
2971 long v = getAndSetLongRelease(o, offset, Double.doubleToRawLongBits(newValue));
2972 return Double.longBitsToDouble(v);
2973 }
2974
2975 @ForceInline
2976 public final double getAndSetDoubleAcquire(Object o, long offset, double newValue) {
2977 long v = getAndSetLongAcquire(o, offset, Double.doubleToRawLongBits(newValue));
2978 return Double.longBitsToDouble(v);
2979 }
2980
2981
2982 // The following contain CAS-based Java implementations used on
2983 // platforms not supporting native instructions
2984
2985 @ForceInline
2986 public final boolean getAndBitwiseOrBoolean(Object o, long offset, boolean mask) {
2987 return byte2bool(getAndBitwiseOrByte(o, offset, bool2byte(mask)));
2988 }
2989
2990 @ForceInline
2991 public final boolean getAndBitwiseOrBooleanRelease(Object o, long offset, boolean mask) {
2992 return byte2bool(getAndBitwiseOrByteRelease(o, offset, bool2byte(mask)));
2993 }
2994
2995 @ForceInline
2996 public final boolean getAndBitwiseOrBooleanAcquire(Object o, long offset, boolean mask) {
2997 return byte2bool(getAndBitwiseOrByteAcquire(o, offset, bool2byte(mask)));
2998 }
2999
3000 @ForceInline
3001 public final boolean getAndBitwiseAndBoolean(Object o, long offset, boolean mask) {
3002 return byte2bool(getAndBitwiseAndByte(o, offset, bool2byte(mask)));
3003 }
3004
3005 @ForceInline
3006 public final boolean getAndBitwiseAndBooleanRelease(Object o, long offset, boolean mask) {
3007 return byte2bool(getAndBitwiseAndByteRelease(o, offset, bool2byte(mask)));
3008 }
3009
3010 @ForceInline
3011 public final boolean getAndBitwiseAndBooleanAcquire(Object o, long offset, boolean mask) {
3012 return byte2bool(getAndBitwiseAndByteAcquire(o, offset, bool2byte(mask)));
3013 }
3014
3015 @ForceInline
3016 public final boolean getAndBitwiseXorBoolean(Object o, long offset, boolean mask) {
3017 return byte2bool(getAndBitwiseXorByte(o, offset, bool2byte(mask)));
3018 }
3019
3020 @ForceInline
3021 public final boolean getAndBitwiseXorBooleanRelease(Object o, long offset, boolean mask) {
3022 return byte2bool(getAndBitwiseXorByteRelease(o, offset, bool2byte(mask)));
3023 }
3024
3025 @ForceInline
3026 public final boolean getAndBitwiseXorBooleanAcquire(Object o, long offset, boolean mask) {
3027 return byte2bool(getAndBitwiseXorByteAcquire(o, offset, bool2byte(mask)));
3028 }
3029
3030
3031 @ForceInline
3032 public final byte getAndBitwiseOrByte(Object o, long offset, byte mask) {
3033 byte current;
3034 do {
3035 current = getByteVolatile(o, offset);
3036 } while (!weakCompareAndSetByte(o, offset,
3037 current, (byte) (current | mask)));
3038 return current;
3039 }
3040
3041 @ForceInline
3042 public final byte getAndBitwiseOrByteRelease(Object o, long offset, byte mask) {
3043 byte current;
3044 do {
3045 current = getByte(o, offset);
3046 } while (!weakCompareAndSetByteRelease(o, offset,
3047 current, (byte) (current | mask)));
3048 return current;
3049 }
3050
3051 @ForceInline
3052 public final byte getAndBitwiseOrByteAcquire(Object o, long offset, byte mask) {
3053 byte current;
3054 do {
3055 // Plain read, the value is a hint, the acquire CAS does the work
3056 current = getByte(o, offset);
3057 } while (!weakCompareAndSetByteAcquire(o, offset,
3058 current, (byte) (current | mask)));
3059 return current;
3060 }
3061
3062 @ForceInline
3063 public final byte getAndBitwiseAndByte(Object o, long offset, byte mask) {
3064 byte current;
3065 do {
3066 current = getByteVolatile(o, offset);
3067 } while (!weakCompareAndSetByte(o, offset,
3068 current, (byte) (current & mask)));
3069 return current;
3070 }
3071
3072 @ForceInline
3073 public final byte getAndBitwiseAndByteRelease(Object o, long offset, byte mask) {
3074 byte current;
3075 do {
3076 current = getByte(o, offset);
3077 } while (!weakCompareAndSetByteRelease(o, offset,
3078 current, (byte) (current & mask)));
3079 return current;
3080 }
3081
3082 @ForceInline
3083 public final byte getAndBitwiseAndByteAcquire(Object o, long offset, byte mask) {
3084 byte current;
3085 do {
3086 // Plain read, the value is a hint, the acquire CAS does the work
3087 current = getByte(o, offset);
3088 } while (!weakCompareAndSetByteAcquire(o, offset,
3089 current, (byte) (current & mask)));
3090 return current;
3091 }
3092
3093 @ForceInline
3094 public final byte getAndBitwiseXorByte(Object o, long offset, byte mask) {
3095 byte current;
3096 do {
3097 current = getByteVolatile(o, offset);
3098 } while (!weakCompareAndSetByte(o, offset,
3099 current, (byte) (current ^ mask)));
3100 return current;
3101 }
3102
3103 @ForceInline
3104 public final byte getAndBitwiseXorByteRelease(Object o, long offset, byte mask) {
3105 byte current;
3106 do {
3107 current = getByte(o, offset);
3108 } while (!weakCompareAndSetByteRelease(o, offset,
3109 current, (byte) (current ^ mask)));
3110 return current;
3111 }
3112
3113 @ForceInline
3114 public final byte getAndBitwiseXorByteAcquire(Object o, long offset, byte mask) {
3115 byte current;
3116 do {
3117 // Plain read, the value is a hint, the acquire CAS does the work
3118 current = getByte(o, offset);
3119 } while (!weakCompareAndSetByteAcquire(o, offset,
3120 current, (byte) (current ^ mask)));
3121 return current;
3122 }
3123
3124
3125 @ForceInline
3126 public final char getAndBitwiseOrChar(Object o, long offset, char mask) {
3127 return s2c(getAndBitwiseOrShort(o, offset, c2s(mask)));
3128 }
3129
3130 @ForceInline
3131 public final char getAndBitwiseOrCharRelease(Object o, long offset, char mask) {
3132 return s2c(getAndBitwiseOrShortRelease(o, offset, c2s(mask)));
3133 }
3134
3135 @ForceInline
3136 public final char getAndBitwiseOrCharAcquire(Object o, long offset, char mask) {
3137 return s2c(getAndBitwiseOrShortAcquire(o, offset, c2s(mask)));
3138 }
3139
3140 @ForceInline
3141 public final char getAndBitwiseAndChar(Object o, long offset, char mask) {
3142 return s2c(getAndBitwiseAndShort(o, offset, c2s(mask)));
3143 }
3144
3145 @ForceInline
3146 public final char getAndBitwiseAndCharRelease(Object o, long offset, char mask) {
3147 return s2c(getAndBitwiseAndShortRelease(o, offset, c2s(mask)));
3148 }
3149
3150 @ForceInline
3151 public final char getAndBitwiseAndCharAcquire(Object o, long offset, char mask) {
3152 return s2c(getAndBitwiseAndShortAcquire(o, offset, c2s(mask)));
3153 }
3154
3155 @ForceInline
3156 public final char getAndBitwiseXorChar(Object o, long offset, char mask) {
3157 return s2c(getAndBitwiseXorShort(o, offset, c2s(mask)));
3158 }
3159
3160 @ForceInline
3161 public final char getAndBitwiseXorCharRelease(Object o, long offset, char mask) {
3162 return s2c(getAndBitwiseXorShortRelease(o, offset, c2s(mask)));
3163 }
3164
3165 @ForceInline
3166 public final char getAndBitwiseXorCharAcquire(Object o, long offset, char mask) {
3167 return s2c(getAndBitwiseXorShortAcquire(o, offset, c2s(mask)));
3168 }
3169
3170
3171 @ForceInline
3172 public final short getAndBitwiseOrShort(Object o, long offset, short mask) {
3173 short current;
3174 do {
3175 current = getShortVolatile(o, offset);
3176 } while (!weakCompareAndSetShort(o, offset,
3177 current, (short) (current | mask)));
3178 return current;
3179 }
3180
3181 @ForceInline
3182 public final short getAndBitwiseOrShortRelease(Object o, long offset, short mask) {
3183 short current;
3184 do {
3185 current = getShort(o, offset);
3186 } while (!weakCompareAndSetShortRelease(o, offset,
3187 current, (short) (current | mask)));
3188 return current;
3189 }
3190
3191 @ForceInline
3192 public final short getAndBitwiseOrShortAcquire(Object o, long offset, short mask) {
3193 short current;
3194 do {
3195 // Plain read, the value is a hint, the acquire CAS does the work
3196 current = getShort(o, offset);
3197 } while (!weakCompareAndSetShortAcquire(o, offset,
3198 current, (short) (current | mask)));
3199 return current;
3200 }
3201
3202 @ForceInline
3203 public final short getAndBitwiseAndShort(Object o, long offset, short mask) {
3204 short current;
3205 do {
3206 current = getShortVolatile(o, offset);
3207 } while (!weakCompareAndSetShort(o, offset,
3208 current, (short) (current & mask)));
3209 return current;
3210 }
3211
3212 @ForceInline
3213 public final short getAndBitwiseAndShortRelease(Object o, long offset, short mask) {
3214 short current;
3215 do {
3216 current = getShort(o, offset);
3217 } while (!weakCompareAndSetShortRelease(o, offset,
3218 current, (short) (current & mask)));
3219 return current;
3220 }
3221
3222 @ForceInline
3223 public final short getAndBitwiseAndShortAcquire(Object o, long offset, short mask) {
3224 short current;
3225 do {
3226 // Plain read, the value is a hint, the acquire CAS does the work
3227 current = getShort(o, offset);
3228 } while (!weakCompareAndSetShortAcquire(o, offset,
3229 current, (short) (current & mask)));
3230 return current;
3231 }
3232
3233 @ForceInline
3234 public final short getAndBitwiseXorShort(Object o, long offset, short mask) {
3235 short current;
3236 do {
3237 current = getShortVolatile(o, offset);
3238 } while (!weakCompareAndSetShort(o, offset,
3239 current, (short) (current ^ mask)));
3240 return current;
3241 }
3242
3243 @ForceInline
3244 public final short getAndBitwiseXorShortRelease(Object o, long offset, short mask) {
3245 short current;
3246 do {
3247 current = getShort(o, offset);
3248 } while (!weakCompareAndSetShortRelease(o, offset,
3249 current, (short) (current ^ mask)));
3250 return current;
3251 }
3252
3253 @ForceInline
3254 public final short getAndBitwiseXorShortAcquire(Object o, long offset, short mask) {
3255 short current;
3256 do {
3257 // Plain read, the value is a hint, the acquire CAS does the work
3258 current = getShort(o, offset);
3259 } while (!weakCompareAndSetShortAcquire(o, offset,
3260 current, (short) (current ^ mask)));
3261 return current;
3262 }
3263
3264
3265 @ForceInline
3266 public final int getAndBitwiseOrInt(Object o, long offset, int mask) {
3267 int current;
3268 do {
3269 current = getIntVolatile(o, offset);
3270 } while (!weakCompareAndSetInt(o, offset,
3271 current, current | mask));
3272 return current;
3273 }
3274
3275 @ForceInline
3276 public final int getAndBitwiseOrIntRelease(Object o, long offset, int mask) {
3277 int current;
3278 do {
3279 current = getInt(o, offset);
3280 } while (!weakCompareAndSetIntRelease(o, offset,
3281 current, current | mask));
3282 return current;
3283 }
3284
3285 @ForceInline
3286 public final int getAndBitwiseOrIntAcquire(Object o, long offset, int mask) {
3287 int current;
3288 do {
3289 // Plain read, the value is a hint, the acquire CAS does the work
3290 current = getInt(o, offset);
3291 } while (!weakCompareAndSetIntAcquire(o, offset,
3292 current, current | mask));
3293 return current;
3294 }
3295
3296 /**
3297 * Atomically replaces the current value of a field or array element within
3298 * the given object with the result of bitwise AND between the current value
3299 * and mask.
3300 *
3301 * @param o object/array to update the field/element in
3302 * @param offset field/element offset
3303 * @param mask the mask value
3304 * @return the previous value
3305 * @since 1.9
3306 */
3307 @ForceInline
3308 public final int getAndBitwiseAndInt(Object o, long offset, int mask) {
3309 int current;
3310 do {
3311 current = getIntVolatile(o, offset);
3312 } while (!weakCompareAndSetInt(o, offset,
3313 current, current & mask));
3314 return current;
3315 }
3316
3317 @ForceInline
3318 public final int getAndBitwiseAndIntRelease(Object o, long offset, int mask) {
3319 int current;
3320 do {
3321 current = getInt(o, offset);
3322 } while (!weakCompareAndSetIntRelease(o, offset,
3323 current, current & mask));
3324 return current;
3325 }
3326
3327 @ForceInline
3328 public final int getAndBitwiseAndIntAcquire(Object o, long offset, int mask) {
3329 int current;
3330 do {
3331 // Plain read, the value is a hint, the acquire CAS does the work
3332 current = getInt(o, offset);
3333 } while (!weakCompareAndSetIntAcquire(o, offset,
3334 current, current & mask));
3335 return current;
3336 }
3337
3338 @ForceInline
3339 public final int getAndBitwiseXorInt(Object o, long offset, int mask) {
3340 int current;
3341 do {
3342 current = getIntVolatile(o, offset);
3343 } while (!weakCompareAndSetInt(o, offset,
3344 current, current ^ mask));
3345 return current;
3346 }
3347
3348 @ForceInline
3349 public final int getAndBitwiseXorIntRelease(Object o, long offset, int mask) {
3350 int current;
3351 do {
3352 current = getInt(o, offset);
3353 } while (!weakCompareAndSetIntRelease(o, offset,
3354 current, current ^ mask));
3355 return current;
3356 }
3357
3358 @ForceInline
3359 public final int getAndBitwiseXorIntAcquire(Object o, long offset, int mask) {
3360 int current;
3361 do {
3362 // Plain read, the value is a hint, the acquire CAS does the work
3363 current = getInt(o, offset);
3364 } while (!weakCompareAndSetIntAcquire(o, offset,
3365 current, current ^ mask));
3366 return current;
3367 }
3368
3369
3370 @ForceInline
3371 public final long getAndBitwiseOrLong(Object o, long offset, long mask) {
3372 long current;
3373 do {
3374 current = getLongVolatile(o, offset);
3375 } while (!weakCompareAndSetLong(o, offset,
3376 current, current | mask));
3377 return current;
3378 }
3379
3380 @ForceInline
3381 public final long getAndBitwiseOrLongRelease(Object o, long offset, long mask) {
3382 long current;
3383 do {
3384 current = getLong(o, offset);
3385 } while (!weakCompareAndSetLongRelease(o, offset,
3386 current, current | mask));
3387 return current;
3388 }
3389
3390 @ForceInline
3391 public final long getAndBitwiseOrLongAcquire(Object o, long offset, long mask) {
3392 long current;
3393 do {
3394 // Plain read, the value is a hint, the acquire CAS does the work
3395 current = getLong(o, offset);
3396 } while (!weakCompareAndSetLongAcquire(o, offset,
3397 current, current | mask));
3398 return current;
3399 }
3400
3401 @ForceInline
3402 public final long getAndBitwiseAndLong(Object o, long offset, long mask) {
3403 long current;
3404 do {
3405 current = getLongVolatile(o, offset);
3406 } while (!weakCompareAndSetLong(o, offset,
3407 current, current & mask));
3408 return current;
3409 }
3410
3411 @ForceInline
3412 public final long getAndBitwiseAndLongRelease(Object o, long offset, long mask) {
3413 long current;
3414 do {
3415 current = getLong(o, offset);
3416 } while (!weakCompareAndSetLongRelease(o, offset,
3417 current, current & mask));
3418 return current;
3419 }
3420
3421 @ForceInline
3422 public final long getAndBitwiseAndLongAcquire(Object o, long offset, long mask) {
3423 long current;
3424 do {
3425 // Plain read, the value is a hint, the acquire CAS does the work
3426 current = getLong(o, offset);
3427 } while (!weakCompareAndSetLongAcquire(o, offset,
3428 current, current & mask));
3429 return current;
3430 }
3431
3432 @ForceInline
3433 public final long getAndBitwiseXorLong(Object o, long offset, long mask) {
3434 long current;
3435 do {
3436 current = getLongVolatile(o, offset);
3437 } while (!weakCompareAndSetLong(o, offset,
3438 current, current ^ mask));
3439 return current;
3440 }
3441
3442 @ForceInline
3443 public final long getAndBitwiseXorLongRelease(Object o, long offset, long mask) {
3444 long current;
3445 do {
3446 current = getLong(o, offset);
3447 } while (!weakCompareAndSetLongRelease(o, offset,
3448 current, current ^ mask));
3449 return current;
3450 }
3451
3452 @ForceInline
3453 public final long getAndBitwiseXorLongAcquire(Object o, long offset, long mask) {
3454 long current;
3455 do {
3456 // Plain read, the value is a hint, the acquire CAS does the work
3457 current = getLong(o, offset);
3458 } while (!weakCompareAndSetLongAcquire(o, offset,
3459 current, current ^ mask));
3460 return current;
3461 }
3462
3463
3464
3465 /**
3466 * Ensures that loads before the fence will not be reordered with loads and
3467 * stores after the fence; a "LoadLoad plus LoadStore barrier".
3468 *
3469 * Corresponds to C11 atomic_thread_fence(memory_order_acquire)
3470 * (an "acquire fence").
3471 *
3472 * A pure LoadLoad fence is not provided, since the addition of LoadStore
3473 * is almost always desired, and most current hardware instructions that
3474 * provide a LoadLoad barrier also provide a LoadStore barrier for free.
3475 * @since 1.8
3476 */
3477 @HotSpotIntrinsicCandidate
3478 public native void loadFence();
3479
3480 /**
3481 * Ensures that loads and stores before the fence will not be reordered with
3482 * stores after the fence; a "StoreStore plus LoadStore barrier".
3483 *
3484 * Corresponds to C11 atomic_thread_fence(memory_order_release)
3485 * (a "release fence").
3486 *
3487 * A pure StoreStore fence is not provided, since the addition of LoadStore
3488 * is almost always desired, and most current hardware instructions that
3489 * provide a StoreStore barrier also provide a LoadStore barrier for free.
3490 * @since 1.8
3491 */
3492 @HotSpotIntrinsicCandidate
3493 public native void storeFence();
3494
3495 /**
3496 * Ensures that loads and stores before the fence will not be reordered
3497 * with loads and stores after the fence. Implies the effects of both
3498 * loadFence() and storeFence(), and in addition, the effect of a StoreLoad
3499 * barrier.
3500 *
3501 * Corresponds to C11 atomic_thread_fence(memory_order_seq_cst).
3502 * @since 1.8
3503 */
3504 @HotSpotIntrinsicCandidate
3505 public native void fullFence();
3506
3507 /**
3508 * Ensures that loads before the fence will not be reordered with
3509 * loads after the fence.
3510 */
3511 public final void loadLoadFence() {
3512 loadFence();
3513 }
3514
3515 /**
3516 * Ensures that stores before the fence will not be reordered with
3517 * stores after the fence.
3518 */
3519 public final void storeStoreFence() {
3520 storeFence();
3521 }
3522
3523
3524 /**
3525 * Throws IllegalAccessError; for use by the VM for access control
3526 * error support.
3527 * @since 1.8
3528 */
3529 private static void throwIllegalAccessError() {
3530 throw new IllegalAccessError();
3531 }
3532
3533 /**
3534 * @return Returns true if the native byte ordering of this
3535 * platform is big-endian, false if it is little-endian.
3536 */
3537 public final boolean isBigEndian() { return BE; }
3538
3539 /**
3540 * @return Returns true if this platform is capable of performing
3541 * accesses at addresses which are not aligned for the type of the
3542 * primitive type being accessed, false otherwise.
3543 */
3544 public final boolean unalignedAccess() { return unalignedAccess; }
3545
3546 /**
3547 * Fetches a value at some byte offset into a given Java object.
3548 * More specifically, fetches a value within the given object
3549 * <code>o</code> at the given offset, or (if <code>o</code> is
3550 * null) from the memory address whose numerical value is the
3551 * given offset. <p>
3552 *
3553 * The specification of this method is the same as {@link
3554 * #getLong(Object, long)} except that the offset does not need to
3555 * have been obtained from {@link #objectFieldOffset} on the
3556 * {@link java.lang.reflect.Field} of some Java field. The value
3557 * in memory is raw data, and need not correspond to any Java
3558 * variable. Unless <code>o</code> is null, the value accessed
3559 * must be entirely within the allocated object. The endianness
3560 * of the value in memory is the endianness of the native platform.
3561 *
3562 * <p> The read will be atomic with respect to the largest power
3563 * of two that divides the GCD of the offset and the storage size.
3564 * For example, getLongUnaligned will make atomic reads of 2-, 4-,
3565 * or 8-byte storage units if the offset is zero mod 2, 4, or 8,
3566 * respectively. There are no other guarantees of atomicity.
3567 * <p>
3568 * 8-byte atomicity is only guaranteed on platforms on which
3569 * support atomic accesses to longs.
3570 *
3571 * @param o Java heap object in which the value resides, if any, else
3572 * null
3573 * @param offset The offset in bytes from the start of the object
3574 * @return the value fetched from the indicated object
3575 * @throws RuntimeException No defined exceptions are thrown, not even
3576 * {@link NullPointerException}
3577 * @since 9
3578 */
3579 @HotSpotIntrinsicCandidate
3580 public final long getLongUnaligned(Object o, long offset) {
3581 if ((offset & 7) == 0) {
3582 return getLong(o, offset);
3583 } else if ((offset & 3) == 0) {
3584 return makeLong(getInt(o, offset),
3585 getInt(o, offset + 4));
3586 } else if ((offset & 1) == 0) {
3587 return makeLong(getShort(o, offset),
3588 getShort(o, offset + 2),
3589 getShort(o, offset + 4),
3590 getShort(o, offset + 6));
3591 } else {
3592 return makeLong(getByte(o, offset),
3593 getByte(o, offset + 1),
3594 getByte(o, offset + 2),
3595 getByte(o, offset + 3),
3596 getByte(o, offset + 4),
3597 getByte(o, offset + 5),
3598 getByte(o, offset + 6),
3599 getByte(o, offset + 7));
3600 }
3601 }
3602 /**
3603 * As {@link #getLongUnaligned(Object, long)} but with an
3604 * additional argument which specifies the endianness of the value
3605 * as stored in memory.
3606 *
3607 * @param o Java heap object in which the variable resides
3608 * @param offset The offset in bytes from the start of the object
3609 * @param bigEndian The endianness of the value
3610 * @return the value fetched from the indicated object
3611 * @since 9
3612 */
3613 public final long getLongUnaligned(Object o, long offset, boolean bigEndian) {
3614 return convEndian(bigEndian, getLongUnaligned(o, offset));
3615 }
3616
3617 /** @see #getLongUnaligned(Object, long) */
3618 @HotSpotIntrinsicCandidate
3619 public final int getIntUnaligned(Object o, long offset) {
3620 if ((offset & 3) == 0) {
3621 return getInt(o, offset);
3622 } else if ((offset & 1) == 0) {
3623 return makeInt(getShort(o, offset),
3624 getShort(o, offset + 2));
3625 } else {
3626 return makeInt(getByte(o, offset),
3627 getByte(o, offset + 1),
3628 getByte(o, offset + 2),
3629 getByte(o, offset + 3));
3630 }
3631 }
3632 /** @see #getLongUnaligned(Object, long, boolean) */
3633 public final int getIntUnaligned(Object o, long offset, boolean bigEndian) {
3634 return convEndian(bigEndian, getIntUnaligned(o, offset));
3635 }
3636
3637 /** @see #getLongUnaligned(Object, long) */
3638 @HotSpotIntrinsicCandidate
3639 public final short getShortUnaligned(Object o, long offset) {
3640 if ((offset & 1) == 0) {
3641 return getShort(o, offset);
3642 } else {
3643 return makeShort(getByte(o, offset),
3644 getByte(o, offset + 1));
3645 }
3646 }
3647 /** @see #getLongUnaligned(Object, long, boolean) */
3648 public final short getShortUnaligned(Object o, long offset, boolean bigEndian) {
3649 return convEndian(bigEndian, getShortUnaligned(o, offset));
3650 }
3651
3652 /** @see #getLongUnaligned(Object, long) */
3653 @HotSpotIntrinsicCandidate
3654 public final char getCharUnaligned(Object o, long offset) {
3655 if ((offset & 1) == 0) {
3656 return getChar(o, offset);
3657 } else {
3658 return (char)makeShort(getByte(o, offset),
3659 getByte(o, offset + 1));
3660 }
3661 }
3662
3663 /** @see #getLongUnaligned(Object, long, boolean) */
3664 public final char getCharUnaligned(Object o, long offset, boolean bigEndian) {
3665 return convEndian(bigEndian, getCharUnaligned(o, offset));
3666 }
3667
3668 /**
3669 * Stores a value at some byte offset into a given Java object.
3670 * <p>
3671 * The specification of this method is the same as {@link
3672 * #getLong(Object, long)} except that the offset does not need to
3673 * have been obtained from {@link #objectFieldOffset} on the
3674 * {@link java.lang.reflect.Field} of some Java field. The value
3675 * in memory is raw data, and need not correspond to any Java
3676 * variable. The endianness of the value in memory is the
3677 * endianness of the native platform.
3678 * <p>
3679 * The write will be atomic with respect to the largest power of
3680 * two that divides the GCD of the offset and the storage size.
3681 * For example, putLongUnaligned will make atomic writes of 2-, 4-,
3682 * or 8-byte storage units if the offset is zero mod 2, 4, or 8,
3683 * respectively. There are no other guarantees of atomicity.
3684 * <p>
3685 * 8-byte atomicity is only guaranteed on platforms on which
3686 * support atomic accesses to longs.
3687 *
3688 * @param o Java heap object in which the value resides, if any, else
3689 * null
3690 * @param offset The offset in bytes from the start of the object
3691 * @param x the value to store
3692 * @throws RuntimeException No defined exceptions are thrown, not even
3693 * {@link NullPointerException}
3694 * @since 9
3695 */
3696 @HotSpotIntrinsicCandidate
3697 public final void putLongUnaligned(Object o, long offset, long x) {
3698 if ((offset & 7) == 0) {
3699 putLong(o, offset, x);
3700 } else if ((offset & 3) == 0) {
3701 putLongParts(o, offset,
3702 (int)(x >> 0),
3703 (int)(x >>> 32));
3704 } else if ((offset & 1) == 0) {
3705 putLongParts(o, offset,
3706 (short)(x >>> 0),
3707 (short)(x >>> 16),
3708 (short)(x >>> 32),
3709 (short)(x >>> 48));
3710 } else {
3711 putLongParts(o, offset,
3712 (byte)(x >>> 0),
3713 (byte)(x >>> 8),
3714 (byte)(x >>> 16),
3715 (byte)(x >>> 24),
3716 (byte)(x >>> 32),
3717 (byte)(x >>> 40),
3718 (byte)(x >>> 48),
3719 (byte)(x >>> 56));
3720 }
3721 }
3722
3723 /**
3724 * As {@link #putLongUnaligned(Object, long, long)} but with an additional
3725 * argument which specifies the endianness of the value as stored in memory.
3726 * @param o Java heap object in which the value resides
3727 * @param offset The offset in bytes from the start of the object
3728 * @param x the value to store
3729 * @param bigEndian The endianness of the value
3730 * @throws RuntimeException No defined exceptions are thrown, not even
3731 * {@link NullPointerException}
3732 * @since 9
3733 */
3734 public final void putLongUnaligned(Object o, long offset, long x, boolean bigEndian) {
3735 putLongUnaligned(o, offset, convEndian(bigEndian, x));
3736 }
3737
3738 /** @see #putLongUnaligned(Object, long, long) */
3739 @HotSpotIntrinsicCandidate
3740 public final void putIntUnaligned(Object o, long offset, int x) {
3741 if ((offset & 3) == 0) {
3742 putInt(o, offset, x);
3743 } else if ((offset & 1) == 0) {
3744 putIntParts(o, offset,
3745 (short)(x >> 0),
3746 (short)(x >>> 16));
3747 } else {
3748 putIntParts(o, offset,
3749 (byte)(x >>> 0),
3750 (byte)(x >>> 8),
3751 (byte)(x >>> 16),
3752 (byte)(x >>> 24));
3753 }
3754 }
3755 /** @see #putLongUnaligned(Object, long, long, boolean) */
3756 public final void putIntUnaligned(Object o, long offset, int x, boolean bigEndian) {
3757 putIntUnaligned(o, offset, convEndian(bigEndian, x));
3758 }
3759
3760 /** @see #putLongUnaligned(Object, long, long) */
3761 @HotSpotIntrinsicCandidate
3762 public final void putShortUnaligned(Object o, long offset, short x) {
3763 if ((offset & 1) == 0) {
3764 putShort(o, offset, x);
3765 } else {
3766 putShortParts(o, offset,
3767 (byte)(x >>> 0),
3768 (byte)(x >>> 8));
3769 }
3770 }
3771 /** @see #putLongUnaligned(Object, long, long, boolean) */
3772 public final void putShortUnaligned(Object o, long offset, short x, boolean bigEndian) {
3773 putShortUnaligned(o, offset, convEndian(bigEndian, x));
3774 }
3775
3776 /** @see #putLongUnaligned(Object, long, long) */
3777 @HotSpotIntrinsicCandidate
3778 public final void putCharUnaligned(Object o, long offset, char x) {
3779 putShortUnaligned(o, offset, (short)x);
3780 }
3781 /** @see #putLongUnaligned(Object, long, long, boolean) */
3782 public final void putCharUnaligned(Object o, long offset, char x, boolean bigEndian) {
3783 putCharUnaligned(o, offset, convEndian(bigEndian, x));
3784 }
3785
3786 // JVM interface methods
3787 // BE is true iff the native endianness of this platform is big.
3788 private static final boolean BE = theUnsafe.isBigEndian0();
3789
3790 // unalignedAccess is true iff this platform can perform unaligned accesses.
3791 private static final boolean unalignedAccess = theUnsafe.unalignedAccess0();
3792
3793 private static int pickPos(int top, int pos) { return BE ? top - pos : pos; }
3794
3795 // These methods construct integers from bytes. The byte ordering
3796 // is the native endianness of this platform.
3797 private static long makeLong(byte i0, byte i1, byte i2, byte i3, byte i4, byte i5, byte i6, byte i7) {
3798 return ((toUnsignedLong(i0) << pickPos(56, 0))
3799 | (toUnsignedLong(i1) << pickPos(56, 8))
3800 | (toUnsignedLong(i2) << pickPos(56, 16))
3801 | (toUnsignedLong(i3) << pickPos(56, 24))
3802 | (toUnsignedLong(i4) << pickPos(56, 32))
3803 | (toUnsignedLong(i5) << pickPos(56, 40))
3804 | (toUnsignedLong(i6) << pickPos(56, 48))
3805 | (toUnsignedLong(i7) << pickPos(56, 56)));
3806 }
3807 private static long makeLong(short i0, short i1, short i2, short i3) {
3808 return ((toUnsignedLong(i0) << pickPos(48, 0))
3809 | (toUnsignedLong(i1) << pickPos(48, 16))
3810 | (toUnsignedLong(i2) << pickPos(48, 32))
3811 | (toUnsignedLong(i3) << pickPos(48, 48)));
3812 }
3813 private static long makeLong(int i0, int i1) {
3814 return (toUnsignedLong(i0) << pickPos(32, 0))
3815 | (toUnsignedLong(i1) << pickPos(32, 32));
3816 }
3817 private static int makeInt(short i0, short i1) {
3818 return (toUnsignedInt(i0) << pickPos(16, 0))
3819 | (toUnsignedInt(i1) << pickPos(16, 16));
3820 }
3821 private static int makeInt(byte i0, byte i1, byte i2, byte i3) {
3822 return ((toUnsignedInt(i0) << pickPos(24, 0))
3823 | (toUnsignedInt(i1) << pickPos(24, 8))
3824 | (toUnsignedInt(i2) << pickPos(24, 16))
3825 | (toUnsignedInt(i3) << pickPos(24, 24)));
3826 }
3827 private static short makeShort(byte i0, byte i1) {
3828 return (short)((toUnsignedInt(i0) << pickPos(8, 0))
3829 | (toUnsignedInt(i1) << pickPos(8, 8)));
3830 }
3831
3832 private static byte pick(byte le, byte be) { return BE ? be : le; }
3833 private static short pick(short le, short be) { return BE ? be : le; }
3834 private static int pick(int le, int be) { return BE ? be : le; }
3835
3836 // These methods write integers to memory from smaller parts
3837 // provided by their caller. The ordering in which these parts
3838 // are written is the native endianness of this platform.
3839 private void putLongParts(Object o, long offset, byte i0, byte i1, byte i2, byte i3, byte i4, byte i5, byte i6, byte i7) {
3840 putByte(o, offset + 0, pick(i0, i7));
3841 putByte(o, offset + 1, pick(i1, i6));
3842 putByte(o, offset + 2, pick(i2, i5));
3843 putByte(o, offset + 3, pick(i3, i4));
3844 putByte(o, offset + 4, pick(i4, i3));
3845 putByte(o, offset + 5, pick(i5, i2));
3846 putByte(o, offset + 6, pick(i6, i1));
3847 putByte(o, offset + 7, pick(i7, i0));
3848 }
3849 private void putLongParts(Object o, long offset, short i0, short i1, short i2, short i3) {
3850 putShort(o, offset + 0, pick(i0, i3));
3851 putShort(o, offset + 2, pick(i1, i2));
3852 putShort(o, offset + 4, pick(i2, i1));
3853 putShort(o, offset + 6, pick(i3, i0));
3854 }
3855 private void putLongParts(Object o, long offset, int i0, int i1) {
3856 putInt(o, offset + 0, pick(i0, i1));
3857 putInt(o, offset + 4, pick(i1, i0));
3858 }
3859 private void putIntParts(Object o, long offset, short i0, short i1) {
3860 putShort(o, offset + 0, pick(i0, i1));
3861 putShort(o, offset + 2, pick(i1, i0));
3862 }
3863 private void putIntParts(Object o, long offset, byte i0, byte i1, byte i2, byte i3) {
3864 putByte(o, offset + 0, pick(i0, i3));
3865 putByte(o, offset + 1, pick(i1, i2));
3866 putByte(o, offset + 2, pick(i2, i1));
3867 putByte(o, offset + 3, pick(i3, i0));
3868 }
3869 private void putShortParts(Object o, long offset, byte i0, byte i1) {
3870 putByte(o, offset + 0, pick(i0, i1));
3871 putByte(o, offset + 1, pick(i1, i0));
3872 }
3873
3874 // Zero-extend an integer
3875 private static int toUnsignedInt(byte n) { return n & 0xff; }
3876 private static int toUnsignedInt(short n) { return n & 0xffff; }
3877 private static long toUnsignedLong(byte n) { return n & 0xffl; }
3878 private static long toUnsignedLong(short n) { return n & 0xffffl; }
3879 private static long toUnsignedLong(int n) { return n & 0xffffffffl; }
3880
3881 // Maybe byte-reverse an integer
3882 private static char convEndian(boolean big, char n) { return big == BE ? n : Character.reverseBytes(n); }
3883 private static short convEndian(boolean big, short n) { return big == BE ? n : Short.reverseBytes(n) ; }
3884 private static int convEndian(boolean big, int n) { return big == BE ? n : Integer.reverseBytes(n) ; }
3885 private static long convEndian(boolean big, long n) { return big == BE ? n : Long.reverseBytes(n) ; }
3886
3887
3888
3889 private native long allocateMemory0(long bytes);
3890 private native long reallocateMemory0(long address, long bytes);
3891 private native void freeMemory0(long address);
3892 private native void setMemory0(Object o, long offset, long bytes, byte value);
3893 @HotSpotIntrinsicCandidate
3894 private native void copyMemory0(Object srcBase, long srcOffset, Object destBase, long destOffset, long bytes);
3895 private native void copySwapMemory0(Object srcBase, long srcOffset, Object destBase, long destOffset, long bytes, long elemSize);
3896 private native long objectFieldOffset0(Field f);
3897 private native long objectFieldOffset1(Class<?> c, String name);
3898 private native long staticFieldOffset0(Field f);
3899 private native Object staticFieldBase0(Field f);
3900 private native boolean shouldBeInitialized0(Class<?> c);
3901 private native void ensureClassInitialized0(Class<?> c);
3902 private native int arrayBaseOffset0(Class<?> arrayClass);
3903 private native int arrayIndexScale0(Class<?> arrayClass);
3904 private native int addressSize0();
3905 private native Class<?> defineAnonymousClass0(Class<?> hostClass, byte[] data, Object[] cpPatches);
3906 private native int getLoadAverage0(double[] loadavg, int nelems);
3907 private native boolean unalignedAccess0();
3908 private native boolean isBigEndian0();
3909
3910
3911 /**
3912 * Invokes the given direct byte buffer's cleaner, if any.
3913 *
3914 * @param directBuffer a direct byte buffer
3915 * @throws NullPointerException if {@code directBuffer} is null
3916 * @throws IllegalArgumentException if {@code directBuffer} is non-direct,
3917 * or is a {@link java.nio.Buffer#slice slice}, or is a
3918 * {@link java.nio.Buffer#duplicate duplicate}
3919 */
3920 public void invokeCleaner(java.nio.ByteBuffer directBuffer) {
3921 if (!directBuffer.isDirect())
3922 throw new IllegalArgumentException("buffer is non-direct");
3923
3924 DirectBuffer db = (DirectBuffer) directBuffer;
3925 if (db.attachment() != null)
3926 throw new IllegalArgumentException("duplicate or slice");
3927
3928 Cleaner cleaner = db.cleaner();
3929 if (cleaner != null) {
3930 cleaner.clean();
3931 }
3932 }
3933
3934 // The following deprecated methods are used by JSR 166.
3935
3936 @Deprecated(since="12", forRemoval=true)
3937 public final Object getObject(Object o, long offset) {
3938 return getReference(o, offset);
3939 }
3940 @Deprecated(since="12", forRemoval=true)
3941 public final Object getObjectVolatile(Object o, long offset) {
3942 return getReferenceVolatile(o, offset);
3943 }
3944 @Deprecated(since="12", forRemoval=true)
3945 public final Object getObjectAcquire(Object o, long offset) {
3946 return getReferenceAcquire(o, offset);
3947 }
3948 @Deprecated(since="12", forRemoval=true)
3949 public final Object getObjectOpaque(Object o, long offset) {
3950 return getReferenceOpaque(o, offset);
3951 }
3952
3953
3954 @Deprecated(since="12", forRemoval=true)
3955 public final void putObject(Object o, long offset, Object x) {
3956 putReference(o, offset, x);
3957 }
3958 @Deprecated(since="12", forRemoval=true)
3959 public final void putObjectVolatile(Object o, long offset, Object x) {
3960 putReferenceVolatile(o, offset, x);
3961 }
3962 @Deprecated(since="12", forRemoval=true)
3963 public final void putObjectOpaque(Object o, long offset, Object x) {
3964 putReferenceOpaque(o, offset, x);
3965 }
3966 @Deprecated(since="12", forRemoval=true)
3967 public final void putObjectRelease(Object o, long offset, Object x) {
3968 putReferenceRelease(o, offset, x);
3969 }
3970
3971
3972 @Deprecated(since="12", forRemoval=true)
3973 public final Object getAndSetObject(Object o, long offset, Object newValue) {
3974 return getAndSetReference(o, offset, newValue);
3975 }
3976 @Deprecated(since="12", forRemoval=true)
3977 public final Object getAndSetObjectAcquire(Object o, long offset, Object newValue) {
3978 return getAndSetReferenceAcquire(o, offset, newValue);
3979 }
3980 @Deprecated(since="12", forRemoval=true)
3981 public final Object getAndSetObjectRelease(Object o, long offset, Object newValue) {
3982 return getAndSetReferenceRelease(o, offset, newValue);
3983 }
3984
3985
3986 @Deprecated(since="12", forRemoval=true)
3987 public final boolean compareAndSetObject(Object o, long offset, Object expected, Object x) {
3988 return compareAndSetReference(o, offset, expected, x);
3989 }
3990 @Deprecated(since="12", forRemoval=true)
3991 public final Object compareAndExchangeObject(Object o, long offset, Object expected, Object x) {
3992 return compareAndExchangeReference(o, offset, expected, x);
3993 }
3994 @Deprecated(since="12", forRemoval=true)
3995 public final Object compareAndExchangeObjectAcquire(Object o, long offset, Object expected, Object x) {
3996 return compareAndExchangeReferenceAcquire(o, offset, expected, x);
3997 }
3998 @Deprecated(since="12", forRemoval=true)
3999 public final Object compareAndExchangeObjectRelease(Object o, long offset, Object expected, Object x) {
4000 return compareAndExchangeReferenceRelease(o, offset, expected, x);
4001 }
4002
4003
4004 @Deprecated(since="12", forRemoval=true)
4005 public final boolean weakCompareAndSetObject(Object o, long offset, Object expected, Object x) {
4006 return weakCompareAndSetReference(o, offset, expected, x);
4007 }
4008 @Deprecated(since="12", forRemoval=true)
4009 public final boolean weakCompareAndSetObjectAcquire(Object o, long offset, Object expected, Object x) {
4010 return weakCompareAndSetReferenceAcquire(o, offset, expected, x);
4011 }
4012 @Deprecated(since="12", forRemoval=true)
4013 public final boolean weakCompareAndSetObjectPlain(Object o, long offset, Object expected, Object x) {
4014 return weakCompareAndSetReferencePlain(o, offset, expected, x);
4015 }
4016 @Deprecated(since="12", forRemoval=true)
4017 public final boolean weakCompareAndSetObjectRelease(Object o, long offset, Object expected, Object x) {
4018 return weakCompareAndSetReferenceRelease(o, offset, expected, x);
4019 }
4020 }