1 /*
2 * Copyright (c) 2000, 2019, 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 import static jdk.internal.misc.UnsafeConstants.*;
37
38 /**
39 * A collection of methods for performing low-level, unsafe operations.
40 * Although the class and all methods are public, use of this class is
41 * limited because only trusted code can obtain instances of it.
42 *
43 * <em>Note:</em> It is the resposibility of the caller to make sure
44 * arguments are checked before methods of this class are
45 * called. While some rudimentary checks are performed on the input,
46 * the checks are best effort and when performance is an overriding
47 * priority, as when methods of this class are optimized by the
48 * runtime compiler, some or all checks (if any) may be elided. Hence,
49 * the caller must not rely on the checks and corresponding
50 * exceptions!
51 *
52 * @author John R. Rose
53 * @see #getUnsafe
54 */
55
56 public final class Unsafe {
57
58 private static native void registerNatives();
59 static {
60 registerNatives();
61 }
62
63 private Unsafe() {}
64
65 private static final Unsafe theUnsafe = new Unsafe();
66
67 /**
68 * Provides the caller with the capability of performing unsafe
69 * operations.
70 *
71 * <p>The returned {@code Unsafe} object should be carefully guarded
72 * by the caller, since it can be used to read and write data at arbitrary
73 * memory addresses. It must never be passed to untrusted code.
74 *
75 * <p>Most methods in this class are very low-level, and correspond to a
76 * small number of hardware instructions (on typical machines). Compilers
77 * are encouraged to optimize these methods accordingly.
78 *
79 * <p>Here is a suggested idiom for using unsafe operations:
80 *
81 * <pre> {@code
82 * class MyTrustedClass {
83 * private static final Unsafe unsafe = Unsafe.getUnsafe();
84 * ...
85 * private long myCountAddress = ...;
86 * public int getCount() { return unsafe.getByte(myCountAddress); }
87 * }}</pre>
88 *
89 * (It may assist compilers to make the local variable {@code final}.)
90 */
91 public static Unsafe getUnsafe() {
92 return theUnsafe;
93 }
94
95 /// peek and poke operations
96 /// (compilers should optimize these to memory ops)
97
98 // These work on object fields in the Java heap.
99 // They will not work on elements of packed arrays.
100
101 /**
102 * Fetches a value from a given Java variable.
103 * More specifically, fetches a field or array element within the given
104 * object {@code o} at the given offset, or (if {@code o} is null)
105 * from the memory address whose numerical value is the given offset.
106 * <p>
107 * The results are undefined unless one of the following cases is true:
108 * <ul>
109 * <li>The offset was obtained from {@link #objectFieldOffset} on
110 * the {@link java.lang.reflect.Field} of some Java field and the object
111 * referred to by {@code o} is of a class compatible with that
112 * field's class.
113 *
114 * <li>The offset and object reference {@code o} (either null or
115 * non-null) were both obtained via {@link #staticFieldOffset}
116 * and {@link #staticFieldBase} (respectively) from the
117 * reflective {@link Field} representation of some Java field.
118 *
119 * <li>The object referred to by {@code o} is an array, and the offset
120 * is an integer of the form {@code B+N*S}, where {@code N} is
121 * a valid index into the array, and {@code B} and {@code S} are
122 * the values obtained by {@link #arrayBaseOffset} and {@link
123 * #arrayIndexScale} (respectively) from the array's class. The value
124 * referred to is the {@code N}<em>th</em> element of the array.
125 *
126 * </ul>
127 * <p>
128 * If one of the above cases is true, the call references a specific Java
129 * variable (field or array element). However, the results are undefined
130 * if that variable is not in fact of the type returned by this method.
131 * <p>
132 * This method refers to a variable by means of two parameters, and so
133 * it provides (in effect) a <em>double-register</em> addressing mode
134 * for Java variables. When the object reference is null, this method
135 * uses its offset as an absolute address. This is similar in operation
136 * to methods such as {@link #getInt(long)}, which provide (in effect) a
137 * <em>single-register</em> addressing mode for non-Java variables.
138 * However, because Java variables may have a different layout in memory
139 * from non-Java variables, programmers should not assume that these
140 * two addressing modes are ever equivalent. Also, programmers should
141 * remember that offsets from the double-register addressing mode cannot
142 * be portably confused with longs used in the single-register addressing
143 * mode.
144 *
145 * @param o Java heap object in which the variable resides, if any, else
146 * null
147 * @param offset indication of where the variable resides in a Java heap
148 * object, if any, else a memory address locating the variable
149 * statically
150 * @return the value fetched from the indicated Java variable
151 * @throws RuntimeException No defined exceptions are thrown, not even
152 * {@link NullPointerException}
153 */
154 @HotSpotIntrinsicCandidate
155 public native int getInt(Object o, long offset);
156
157 /**
158 * Stores a value into a given Java variable.
159 * <p>
160 * The first two parameters are interpreted exactly as with
161 * {@link #getInt(Object, long)} to refer to a specific
162 * Java variable (field or array element). The given value
163 * is stored into that variable.
164 * <p>
165 * The variable must be of the same type as the method
166 * parameter {@code x}.
167 *
168 * @param o Java heap object in which the variable resides, if any, else
169 * null
170 * @param offset indication of where the variable resides in a Java heap
171 * object, if any, else a memory address locating the variable
172 * statically
173 * @param x the value to store into the indicated Java variable
174 * @throws RuntimeException No defined exceptions are thrown, not even
175 * {@link NullPointerException}
176 */
177 @HotSpotIntrinsicCandidate
178 public native void putInt(Object o, long offset, int x);
179
180 private static final int JVM_ACC_FLATTENED = 0x00008000; // HotSpot-specific bit
181
182 /**
183 * Returns true if the given field is flattened.
184 */
185 public boolean isFlattened(Field f) {
186 return (f.getModifiers() & JVM_ACC_FLATTENED) == JVM_ACC_FLATTENED;
187 }
188
189 /**
190 * Returns true if the given class is a flattened array.
191 */
192 public native boolean isFlattenedArray(Class<?> arrayClass);
193
194 /**
195 * Fetches a reference value from a given Java variable.
196 * This method can return a reference to either an object or value
197 * or a null reference.
198 *
199 * @see #getInt(Object, long)
200 */
201 @HotSpotIntrinsicCandidate
202 public native Object getReference(Object o, long offset);
203
204 /**
205 * Stores a reference value into a given Java variable.
206 * This method can store a reference to either an object or value
207 * or a null reference.
208 * <p>
209 * Unless the reference {@code x} being stored is either null
210 * or matches the field type, the results are undefined.
211 * If the reference {@code o} is non-null, card marks or
212 * other store barriers for that object (if the VM requires them)
213 * are updated.
214 * @see #putInt(Object, long, int)
215 */
216 @HotSpotIntrinsicCandidate
217 public native void putReference(Object o, long offset, Object x);
218
219 /**
220 * Fetches a value of type {@code <V>} from a given Java variable.
221 * More specifically, fetches a field or array element within the given
222 * {@code o} object at the given offset, or (if {@code o} is null)
223 * from the memory address whose numerical value is the given offset.
224 *
225 * @param o Java heap object in which the variable resides, if any, else
226 * null
227 * @param offset indication of where the variable resides in a Java heap
228 * object, if any, else a memory address locating the variable
229 * statically
230 * @param vc inline class
231 * @param <V> the type of a value
232 * @return the value fetched from the indicated Java variable
233 * @throws RuntimeException No defined exceptions are thrown, not even
234 * {@link NullPointerException}
235 */
236 @HotSpotIntrinsicCandidate
237 public native <V> V getValue(Object o, long offset, Class<?> vc);
238
239 /**
240 * Stores the given value into a given Java variable.
241 *
242 * Unless the reference {@code o} being stored is either null
243 * or matches the field type, the results are undefined.
244 *
245 * @param o Java heap object in which the variable resides, if any, else
246 * null
247 * @param offset indication of where the variable resides in a Java heap
248 * object, if any, else a memory address locating the variable
249 * statically
250 * @param vc inline class
251 * @param v the value to store into the indicated Java variable
252 * @param <V> the type of a value
253 * @throws RuntimeException No defined exceptions are thrown, not even
254 * {@link NullPointerException}
255 */
256 @HotSpotIntrinsicCandidate
257 public native <V> void putValue(Object o, long offset, Class<?> vc, V v);
258
259 /**
260 * Fetches a reference value of type {@code vc} from a given Java variable.
261 * This method can return a reference to a value or a null reference
262 * for a nullable-projection of an inline type.
263 *
264 * @param vc inline class
265 */
266 public Object getReference(Object o, long offset, Class<?> vc) {
267 Object ref = getReference(o, offset);
268 if (ref == null && vc.isInlineClass() && !vc.isIndirectType()) {
269 // If the type of the returned reference is a regular inline type
270 // return an uninitialized default value if null
271 ref = uninitializedDefaultValue(vc);
272 }
273 return ref;
274 }
275
276 public Object getReferenceVolatile(Object o, long offset, Class<?> vc) {
277 Object ref = getReferenceVolatile(o, offset);
278 if (ref == null && vc.isInlineClass() && !vc.isIndirectType()) {
279 // If the type of the returned reference is a regular inline type
280 // return an uninitialized default value if null
281 ref = uninitializedDefaultValue(vc);
282 }
283 return ref;
284 }
285
286 /**
287 * Returns an uninitialized default value of the given inline class.
288 */
289 public native <V> V uninitializedDefaultValue(Class<?> vc);
290
291 /**
292 * Returns an object instance with a private buffered value whose layout
293 * and contents is exactly the given value instance. The return object
294 * is in the larval state that can be updated using the unsafe put operation.
295 *
296 * @param value a value instance
297 * @param <V> the type of the given value instance
298 */
299 @HotSpotIntrinsicCandidate
300 public native <V> V makePrivateBuffer(V value);
301
302 /**
303 * Exits the larval state and returns a value instance.
304 *
305 * @param value a value instance
306 * @param <V> the type of the given value instance
307 */
308 @HotSpotIntrinsicCandidate
309 public native <V> V finishPrivateBuffer(V value);
310
311 /**
312 * Returns the header size of the given inline class
313 *
314 * @param vc inline class
315 * @param <V> value clas
316 * @return the header size of the inline class
317 */
318 public native <V> long valueHeaderSize(Class<V> vc);
319
320 /** @see #getInt(Object, long) */
321 @HotSpotIntrinsicCandidate
322 public native boolean getBoolean(Object o, long offset);
323
324 /** @see #putInt(Object, long, int) */
325 @HotSpotIntrinsicCandidate
326 public native void putBoolean(Object o, long offset, boolean x);
327
328 /** @see #getInt(Object, long) */
329 @HotSpotIntrinsicCandidate
330 public native byte getByte(Object o, long offset);
331
332 /** @see #putInt(Object, long, int) */
333 @HotSpotIntrinsicCandidate
334 public native void putByte(Object o, long offset, byte x);
335
336 /** @see #getInt(Object, long) */
337 @HotSpotIntrinsicCandidate
338 public native short getShort(Object o, long offset);
339
340 /** @see #putInt(Object, long, int) */
341 @HotSpotIntrinsicCandidate
342 public native void putShort(Object o, long offset, short x);
343
344 /** @see #getInt(Object, long) */
345 @HotSpotIntrinsicCandidate
346 public native char getChar(Object o, long offset);
347
348 /** @see #putInt(Object, long, int) */
349 @HotSpotIntrinsicCandidate
350 public native void putChar(Object o, long offset, char x);
351
352 /** @see #getInt(Object, long) */
353 @HotSpotIntrinsicCandidate
354 public native long getLong(Object o, long offset);
355
356 /** @see #putInt(Object, long, int) */
357 @HotSpotIntrinsicCandidate
358 public native void putLong(Object o, long offset, long x);
359
360 /** @see #getInt(Object, long) */
361 @HotSpotIntrinsicCandidate
362 public native float getFloat(Object o, long offset);
363
364 /** @see #putInt(Object, long, int) */
365 @HotSpotIntrinsicCandidate
366 public native void putFloat(Object o, long offset, float x);
367
368 /** @see #getInt(Object, long) */
369 @HotSpotIntrinsicCandidate
370 public native double getDouble(Object o, long offset);
371
372 /** @see #putInt(Object, long, int) */
373 @HotSpotIntrinsicCandidate
374 public native void putDouble(Object o, long offset, double x);
375
376 /**
377 * Fetches a native pointer from a given memory address. If the address is
378 * zero, or does not point into a block obtained from {@link
379 * #allocateMemory}, the results are undefined.
380 *
381 * <p>If the native pointer is less than 64 bits wide, it is extended as
382 * an unsigned number to a Java long. The pointer may be indexed by any
383 * given byte offset, simply by adding that offset (as a simple integer) to
384 * the long representing the pointer. The number of bytes actually read
385 * from the target address may be determined by consulting {@link
386 * #addressSize}.
387 *
388 * @see #allocateMemory
389 * @see #getInt(Object, long)
390 */
391 @ForceInline
392 public long getAddress(Object o, long offset) {
393 if (ADDRESS_SIZE == 4) {
394 return Integer.toUnsignedLong(getInt(o, offset));
395 } else {
396 return getLong(o, offset);
397 }
398 }
399
400 /**
401 * Stores a native pointer into a given memory address. If the address is
402 * zero, or does not point into a block obtained from {@link
403 * #allocateMemory}, the results are undefined.
404 *
405 * <p>The number of bytes actually written at the target address may be
406 * determined by consulting {@link #addressSize}.
407 *
408 * @see #allocateMemory
409 * @see #putInt(Object, long, int)
410 */
411 @ForceInline
412 public void putAddress(Object o, long offset, long x) {
413 if (ADDRESS_SIZE == 4) {
414 putInt(o, offset, (int)x);
415 } else {
416 putLong(o, offset, x);
417 }
418 }
419
420 // These read VM internal data.
421
422 /**
423 * Fetches an uncompressed reference value from a given native variable
424 * ignoring the VM's compressed references mode.
425 *
426 * @param address a memory address locating the variable
427 * @return the value fetched from the indicated native variable
428 */
429 public native Object getUncompressedObject(long address);
430
431 // These work on values in the C heap.
432
433 /**
434 * Fetches a value from a given memory address. If the address is zero, or
435 * does not point into a block obtained from {@link #allocateMemory}, the
436 * results are undefined.
437 *
438 * @see #allocateMemory
439 */
440 @ForceInline
441 public byte getByte(long address) {
442 return getByte(null, address);
443 }
444
445 /**
446 * Stores a value into a given memory address. If the address is zero, or
447 * does not point into a block obtained from {@link #allocateMemory}, the
448 * results are undefined.
449 *
450 * @see #getByte(long)
451 */
452 @ForceInline
453 public void putByte(long address, byte x) {
454 putByte(null, address, x);
455 }
456
457 /** @see #getByte(long) */
458 @ForceInline
459 public short getShort(long address) {
460 return getShort(null, address);
461 }
462
463 /** @see #putByte(long, byte) */
464 @ForceInline
465 public void putShort(long address, short x) {
466 putShort(null, address, x);
467 }
468
469 /** @see #getByte(long) */
470 @ForceInline
471 public char getChar(long address) {
472 return getChar(null, address);
473 }
474
475 /** @see #putByte(long, byte) */
476 @ForceInline
477 public void putChar(long address, char x) {
478 putChar(null, address, x);
479 }
480
481 /** @see #getByte(long) */
482 @ForceInline
483 public int getInt(long address) {
484 return getInt(null, address);
485 }
486
487 /** @see #putByte(long, byte) */
488 @ForceInline
489 public void putInt(long address, int x) {
490 putInt(null, address, x);
491 }
492
493 /** @see #getByte(long) */
494 @ForceInline
495 public long getLong(long address) {
496 return getLong(null, address);
497 }
498
499 /** @see #putByte(long, byte) */
500 @ForceInline
501 public void putLong(long address, long x) {
502 putLong(null, address, x);
503 }
504
505 /** @see #getByte(long) */
506 @ForceInline
507 public float getFloat(long address) {
508 return getFloat(null, address);
509 }
510
511 /** @see #putByte(long, byte) */
512 @ForceInline
513 public void putFloat(long address, float x) {
514 putFloat(null, address, x);
515 }
516
517 /** @see #getByte(long) */
518 @ForceInline
519 public double getDouble(long address) {
520 return getDouble(null, address);
521 }
522
523 /** @see #putByte(long, byte) */
524 @ForceInline
525 public void putDouble(long address, double x) {
526 putDouble(null, address, x);
527 }
528
529 /** @see #getAddress(Object, long) */
530 @ForceInline
531 public long getAddress(long address) {
532 return getAddress(null, address);
533 }
534
535 /** @see #putAddress(Object, long, long) */
536 @ForceInline
537 public void putAddress(long address, long x) {
538 putAddress(null, address, x);
539 }
540
541
542
543 /// helper methods for validating various types of objects/values
544
545 /**
546 * Create an exception reflecting that some of the input was invalid
547 *
548 * <em>Note:</em> It is the resposibility of the caller to make
549 * sure arguments are checked before the methods are called. While
550 * some rudimentary checks are performed on the input, the checks
551 * are best effort and when performance is an overriding priority,
552 * as when methods of this class are optimized by the runtime
553 * compiler, some or all checks (if any) may be elided. Hence, the
554 * caller must not rely on the checks and corresponding
555 * exceptions!
556 *
557 * @return an exception object
558 */
559 private RuntimeException invalidInput() {
560 return new IllegalArgumentException();
561 }
562
563 /**
564 * Check if a value is 32-bit clean (32 MSB are all zero)
565 *
566 * @param value the 64-bit value to check
567 *
568 * @return true if the value is 32-bit clean
569 */
570 private boolean is32BitClean(long value) {
571 return value >>> 32 == 0;
572 }
573
574 /**
575 * Check the validity of a size (the equivalent of a size_t)
576 *
577 * @throws RuntimeException if the size is invalid
578 * (<em>Note:</em> after optimization, invalid inputs may
579 * go undetected, which will lead to unpredictable
580 * behavior)
581 */
582 private void checkSize(long size) {
583 if (ADDRESS_SIZE == 4) {
584 // Note: this will also check for negative sizes
585 if (!is32BitClean(size)) {
586 throw invalidInput();
587 }
588 } else if (size < 0) {
589 throw invalidInput();
590 }
591 }
592
593 /**
594 * Check the validity of a native address (the equivalent of void*)
595 *
596 * @throws RuntimeException if the address is invalid
597 * (<em>Note:</em> after optimization, invalid inputs may
598 * go undetected, which will lead to unpredictable
599 * behavior)
600 */
601 private void checkNativeAddress(long address) {
602 if (ADDRESS_SIZE == 4) {
603 // Accept both zero and sign extended pointers. A valid
604 // pointer will, after the +1 below, either have produced
605 // the value 0x0 or 0x1. Masking off the low bit allows
606 // for testing against 0.
607 if ((((address >> 32) + 1) & ~1) != 0) {
608 throw invalidInput();
609 }
610 }
611 }
612
613 /**
614 * Check the validity of an offset, relative to a base object
615 *
616 * @param o the base object
617 * @param offset the offset to check
618 *
619 * @throws RuntimeException if the size is invalid
620 * (<em>Note:</em> after optimization, invalid inputs may
621 * go undetected, which will lead to unpredictable
622 * behavior)
623 */
624 private void checkOffset(Object o, long offset) {
625 if (ADDRESS_SIZE == 4) {
626 // Note: this will also check for negative offsets
627 if (!is32BitClean(offset)) {
628 throw invalidInput();
629 }
630 } else if (offset < 0) {
631 throw invalidInput();
632 }
633 }
634
635 /**
636 * Check the validity of a double-register pointer
637 *
638 * Note: This code deliberately does *not* check for NPE for (at
639 * least) three reasons:
640 *
641 * 1) NPE is not just NULL/0 - there is a range of values all
642 * resulting in an NPE, which is not trivial to check for
643 *
644 * 2) It is the responsibility of the callers of Unsafe methods
645 * to verify the input, so throwing an exception here is not really
646 * useful - passing in a NULL pointer is a critical error and the
647 * must not expect an exception to be thrown anyway.
648 *
649 * 3) the actual operations will detect NULL pointers anyway by
650 * means of traps and signals (like SIGSEGV).
651 *
652 * @param o Java heap object, or null
653 * @param offset indication of where the variable resides in a Java heap
654 * object, if any, else a memory address locating the variable
655 * statically
656 *
657 * @throws RuntimeException if the pointer is invalid
658 * (<em>Note:</em> after optimization, invalid inputs may
659 * go undetected, which will lead to unpredictable
660 * behavior)
661 */
662 private void checkPointer(Object o, long offset) {
663 if (o == null) {
664 checkNativeAddress(offset);
665 } else {
666 checkOffset(o, offset);
667 }
668 }
669
670 /**
671 * Check if a type is a primitive array type
672 *
673 * @param c the type to check
674 *
675 * @return true if the type is a primitive array type
676 */
677 private void checkPrimitiveArray(Class<?> c) {
678 Class<?> componentType = c.getComponentType();
679 if (componentType == null || !componentType.isPrimitive()) {
680 throw invalidInput();
681 }
682 }
683
684 /**
685 * Check that a pointer is a valid primitive array type pointer
686 *
687 * Note: pointers off-heap are considered to be primitive arrays
688 *
689 * @throws RuntimeException if the pointer is invalid
690 * (<em>Note:</em> after optimization, invalid inputs may
691 * go undetected, which will lead to unpredictable
692 * behavior)
693 */
694 private void checkPrimitivePointer(Object o, long offset) {
695 checkPointer(o, offset);
696
697 if (o != null) {
698 // If on heap, it must be a primitive array
699 checkPrimitiveArray(o.getClass());
700 }
701 }
702
703
704 /// wrappers for malloc, realloc, free:
705
706 /**
707 * Allocates a new block of native memory, of the given size in bytes. The
708 * contents of the memory are uninitialized; they will generally be
709 * garbage. The resulting native pointer will never be zero, and will be
710 * aligned for all value types. Dispose of this memory by calling {@link
711 * #freeMemory}, or resize it with {@link #reallocateMemory}.
712 *
713 * <em>Note:</em> It is the resposibility of the caller to make
714 * sure arguments are checked before the methods are called. While
715 * some rudimentary checks are performed on the input, the checks
716 * are best effort and when performance is an overriding priority,
717 * as when methods of this class are optimized by the runtime
718 * compiler, some or all checks (if any) may be elided. Hence, the
719 * caller must not rely on the checks and corresponding
720 * exceptions!
721 *
722 * @throws RuntimeException if the size is negative or too large
723 * for the native size_t type
724 *
725 * @throws OutOfMemoryError if the allocation is refused by the system
726 *
727 * @see #getByte(long)
728 * @see #putByte(long, byte)
729 */
730 public long allocateMemory(long bytes) {
731 allocateMemoryChecks(bytes);
732
733 if (bytes == 0) {
734 return 0;
735 }
736
737 long p = allocateMemory0(bytes);
738 if (p == 0) {
739 throw new OutOfMemoryError();
740 }
741
742 return p;
743 }
744
745 /**
746 * Validate the arguments to allocateMemory
747 *
748 * @throws RuntimeException if the arguments are invalid
749 * (<em>Note:</em> after optimization, invalid inputs may
750 * go undetected, which will lead to unpredictable
751 * behavior)
752 */
753 private void allocateMemoryChecks(long bytes) {
754 checkSize(bytes);
755 }
756
757 /**
758 * Resizes a new block of native memory, to the given size in bytes. The
759 * contents of the new block past the size of the old block are
760 * uninitialized; they will generally be garbage. The resulting native
761 * pointer will be zero if and only if the requested size is zero. The
762 * resulting native pointer will be aligned for all value types. Dispose
763 * of this memory by calling {@link #freeMemory}, or resize it with {@link
764 * #reallocateMemory}. The address passed to this method may be null, in
765 * which case an allocation will be performed.
766 *
767 * <em>Note:</em> It is the resposibility of the caller to make
768 * sure arguments are checked before the methods are called. While
769 * some rudimentary checks are performed on the input, the checks
770 * are best effort and when performance is an overriding priority,
771 * as when methods of this class are optimized by the runtime
772 * compiler, some or all checks (if any) may be elided. Hence, the
773 * caller must not rely on the checks and corresponding
774 * exceptions!
775 *
776 * @throws RuntimeException if the size is negative or too large
777 * for the native size_t type
778 *
779 * @throws OutOfMemoryError if the allocation is refused by the system
780 *
781 * @see #allocateMemory
782 */
783 public long reallocateMemory(long address, long bytes) {
784 reallocateMemoryChecks(address, bytes);
785
786 if (bytes == 0) {
787 freeMemory(address);
788 return 0;
789 }
790
791 long p = (address == 0) ? allocateMemory0(bytes) : reallocateMemory0(address, bytes);
792 if (p == 0) {
793 throw new OutOfMemoryError();
794 }
795
796 return p;
797 }
798
799 /**
800 * Validate the arguments to reallocateMemory
801 *
802 * @throws RuntimeException if the arguments are invalid
803 * (<em>Note:</em> after optimization, invalid inputs may
804 * go undetected, which will lead to unpredictable
805 * behavior)
806 */
807 private void reallocateMemoryChecks(long address, long bytes) {
808 checkPointer(null, address);
809 checkSize(bytes);
810 }
811
812 /**
813 * Sets all bytes in a given block of memory to a fixed value
814 * (usually zero).
815 *
816 * <p>This method determines a block's base address by means of two parameters,
817 * and so it provides (in effect) a <em>double-register</em> addressing mode,
818 * as discussed in {@link #getInt(Object,long)}. When the object reference is null,
819 * the offset supplies an absolute base address.
820 *
821 * <p>The stores are in coherent (atomic) units of a size determined
822 * by the address and length parameters. If the effective address and
823 * length are all even modulo 8, the stores take place in 'long' units.
824 * If the effective address and length are (resp.) even modulo 4 or 2,
825 * the stores take place in units of 'int' or 'short'.
826 *
827 * <em>Note:</em> It is the resposibility of the caller to make
828 * sure arguments are checked before the methods are called. While
829 * some rudimentary checks are performed on the input, the checks
830 * are best effort and when performance is an overriding priority,
831 * as when methods of this class are optimized by the runtime
832 * compiler, some or all checks (if any) may be elided. Hence, the
833 * caller must not rely on the checks and corresponding
834 * exceptions!
835 *
836 * @throws RuntimeException if any of the arguments is invalid
837 *
838 * @since 1.7
839 */
840 public void setMemory(Object o, long offset, long bytes, byte value) {
841 setMemoryChecks(o, offset, bytes, value);
842
843 if (bytes == 0) {
844 return;
845 }
846
847 setMemory0(o, offset, bytes, value);
848 }
849
850 /**
851 * Sets all bytes in a given block of memory to a fixed value
852 * (usually zero). This provides a <em>single-register</em> addressing mode,
853 * as discussed in {@link #getInt(Object,long)}.
854 *
855 * <p>Equivalent to {@code setMemory(null, address, bytes, value)}.
856 */
857 public void setMemory(long address, long bytes, byte value) {
858 setMemory(null, address, bytes, value);
859 }
860
861 /**
862 * Validate the arguments to setMemory
863 *
864 * @throws RuntimeException if the arguments are invalid
865 * (<em>Note:</em> after optimization, invalid inputs may
866 * go undetected, which will lead to unpredictable
867 * behavior)
868 */
869 private void setMemoryChecks(Object o, long offset, long bytes, byte value) {
870 checkPrimitivePointer(o, offset);
871 checkSize(bytes);
872 }
873
874 /**
875 * Sets all bytes in a given block of memory to a copy of another
876 * block.
877 *
878 * <p>This method determines each block's base address by means of two parameters,
879 * and so it provides (in effect) a <em>double-register</em> addressing mode,
880 * as discussed in {@link #getInt(Object,long)}. When the object reference is null,
881 * the offset supplies an absolute base address.
882 *
883 * <p>The transfers are in coherent (atomic) units of a size determined
884 * by the address and length parameters. If the effective addresses and
885 * length are all even modulo 8, the transfer takes place in 'long' units.
886 * If the effective addresses and length are (resp.) even modulo 4 or 2,
887 * the transfer takes place in units of 'int' or 'short'.
888 *
889 * <em>Note:</em> It is the resposibility of the caller to make
890 * sure arguments are checked before the methods are called. While
891 * some rudimentary checks are performed on the input, the checks
892 * are best effort and when performance is an overriding priority,
893 * as when methods of this class are optimized by the runtime
894 * compiler, some or all checks (if any) may be elided. Hence, the
895 * caller must not rely on the checks and corresponding
896 * exceptions!
897 *
898 * @throws RuntimeException if any of the arguments is invalid
899 *
900 * @since 1.7
901 */
902 public void copyMemory(Object srcBase, long srcOffset,
903 Object destBase, long destOffset,
904 long bytes) {
905 copyMemoryChecks(srcBase, srcOffset, destBase, destOffset, bytes);
906
907 if (bytes == 0) {
908 return;
909 }
910
911 copyMemory0(srcBase, srcOffset, destBase, destOffset, bytes);
912 }
913
914 /**
915 * Sets all bytes in a given block of memory to a copy of another
916 * block. This provides a <em>single-register</em> addressing mode,
917 * as discussed in {@link #getInt(Object,long)}.
918 *
919 * Equivalent to {@code copyMemory(null, srcAddress, null, destAddress, bytes)}.
920 */
921 public void copyMemory(long srcAddress, long destAddress, long bytes) {
922 copyMemory(null, srcAddress, null, destAddress, bytes);
923 }
924
925 /**
926 * Validate the arguments to copyMemory
927 *
928 * @throws RuntimeException if any of the arguments is invalid
929 * (<em>Note:</em> after optimization, invalid inputs may
930 * go undetected, which will lead to unpredictable
931 * behavior)
932 */
933 private void copyMemoryChecks(Object srcBase, long srcOffset,
934 Object destBase, long destOffset,
935 long bytes) {
936 checkSize(bytes);
937 checkPrimitivePointer(srcBase, srcOffset);
938 checkPrimitivePointer(destBase, destOffset);
939 }
940
941 /**
942 * Copies all elements from one block of memory to another block,
943 * *unconditionally* byte swapping the elements on the fly.
944 *
945 * <p>This method determines each block's base address by means of two parameters,
946 * and so it provides (in effect) a <em>double-register</em> addressing mode,
947 * as discussed in {@link #getInt(Object,long)}. When the object reference is null,
948 * the offset supplies an absolute base address.
949 *
950 * <em>Note:</em> It is the resposibility of the caller to make
951 * sure arguments are checked before the methods are called. While
952 * some rudimentary checks are performed on the input, the checks
953 * are best effort and when performance is an overriding priority,
954 * as when methods of this class are optimized by the runtime
955 * compiler, some or all checks (if any) may be elided. Hence, the
956 * caller must not rely on the checks and corresponding
957 * exceptions!
958 *
959 * @throws RuntimeException if any of the arguments is invalid
960 *
961 * @since 9
962 */
963 public void copySwapMemory(Object srcBase, long srcOffset,
964 Object destBase, long destOffset,
965 long bytes, long elemSize) {
966 copySwapMemoryChecks(srcBase, srcOffset, destBase, destOffset, bytes, elemSize);
967
968 if (bytes == 0) {
969 return;
970 }
971
972 copySwapMemory0(srcBase, srcOffset, destBase, destOffset, bytes, elemSize);
973 }
974
975 private void copySwapMemoryChecks(Object srcBase, long srcOffset,
976 Object destBase, long destOffset,
977 long bytes, long elemSize) {
978 checkSize(bytes);
979
980 if (elemSize != 2 && elemSize != 4 && elemSize != 8) {
981 throw invalidInput();
982 }
983 if (bytes % elemSize != 0) {
984 throw invalidInput();
985 }
986
987 checkPrimitivePointer(srcBase, srcOffset);
988 checkPrimitivePointer(destBase, destOffset);
989 }
990
991 /**
992 * Copies all elements from one block of memory to another block, byte swapping the
993 * elements on the fly.
994 *
995 * This provides a <em>single-register</em> addressing mode, as
996 * discussed in {@link #getInt(Object,long)}.
997 *
998 * Equivalent to {@code copySwapMemory(null, srcAddress, null, destAddress, bytes, elemSize)}.
999 */
1000 public void copySwapMemory(long srcAddress, long destAddress, long bytes, long elemSize) {
1001 copySwapMemory(null, srcAddress, null, destAddress, bytes, elemSize);
1002 }
1003
1004 /**
1005 * Disposes of a block of native memory, as obtained from {@link
1006 * #allocateMemory} or {@link #reallocateMemory}. The address passed to
1007 * this method may be null, in which case no action is taken.
1008 *
1009 * <em>Note:</em> It is the resposibility of the caller to make
1010 * sure arguments are checked before the methods are called. While
1011 * some rudimentary checks are performed on the input, the checks
1012 * are best effort and when performance is an overriding priority,
1013 * as when methods of this class are optimized by the runtime
1014 * compiler, some or all checks (if any) may be elided. Hence, the
1015 * caller must not rely on the checks and corresponding
1016 * exceptions!
1017 *
1018 * @throws RuntimeException if any of the arguments is invalid
1019 *
1020 * @see #allocateMemory
1021 */
1022 public void freeMemory(long address) {
1023 freeMemoryChecks(address);
1024
1025 if (address == 0) {
1026 return;
1027 }
1028
1029 freeMemory0(address);
1030 }
1031
1032 /**
1033 * Validate the arguments to freeMemory
1034 *
1035 * @throws RuntimeException if the arguments are invalid
1036 * (<em>Note:</em> after optimization, invalid inputs may
1037 * go undetected, which will lead to unpredictable
1038 * behavior)
1039 */
1040 private void freeMemoryChecks(long address) {
1041 checkPointer(null, address);
1042 }
1043
1044 /// random queries
1045
1046 /**
1047 * This constant differs from all results that will ever be returned from
1048 * {@link #staticFieldOffset}, {@link #objectFieldOffset},
1049 * or {@link #arrayBaseOffset}.
1050 */
1051 public static final int INVALID_FIELD_OFFSET = -1;
1052
1053 /**
1054 * Reports the location of a given field in the storage allocation of its
1055 * class. Do not expect to perform any sort of arithmetic on this offset;
1056 * it is just a cookie which is passed to the unsafe heap memory accessors.
1057 *
1058 * <p>Any given field will always have the same offset and base, and no
1059 * two distinct fields of the same class will ever have the same offset
1060 * and base.
1061 *
1062 * <p>As of 1.4.1, offsets for fields are represented as long values,
1063 * although the Sun JVM does not use the most significant 32 bits.
1064 * However, JVM implementations which store static fields at absolute
1065 * addresses can use long offsets and null base pointers to express
1066 * the field locations in a form usable by {@link #getInt(Object,long)}.
1067 * Therefore, code which will be ported to such JVMs on 64-bit platforms
1068 * must preserve all bits of static field offsets.
1069 * @see #getInt(Object, long)
1070 */
1071 public long objectFieldOffset(Field f) {
1072 if (f == null) {
1073 throw new NullPointerException();
1074 }
1075
1076 return objectFieldOffset0(f);
1077 }
1078
1079 /**
1080 * Reports the location of the field with a given name in the storage
1081 * allocation of its class.
1082 *
1083 * @throws NullPointerException if any parameter is {@code null}.
1084 * @throws InternalError if there is no field named {@code name} declared
1085 * in class {@code c}, i.e., if {@code c.getDeclaredField(name)}
1086 * would throw {@code java.lang.NoSuchFieldException}.
1087 *
1088 * @see #objectFieldOffset(Field)
1089 */
1090 public long objectFieldOffset(Class<?> c, String name) {
1091 if (c == null || name == null) {
1092 throw new NullPointerException();
1093 }
1094
1095 return objectFieldOffset1(c, name);
1096 }
1097
1098 /**
1099 * Reports the location of a given static field, in conjunction with {@link
1100 * #staticFieldBase}.
1101 * <p>Do not expect to perform any sort of arithmetic on this offset;
1102 * it is just a cookie which is passed to the unsafe heap memory accessors.
1103 *
1104 * <p>Any given field will always have the same offset, and no two distinct
1105 * fields of the same class will ever have the same offset.
1106 *
1107 * <p>As of 1.4.1, offsets for fields are represented as long values,
1108 * although the Sun JVM does not use the most significant 32 bits.
1109 * It is hard to imagine a JVM technology which needs more than
1110 * a few bits to encode an offset within a non-array object,
1111 * However, for consistency with other methods in this class,
1112 * this method reports its result as a long value.
1113 * @see #getInt(Object, long)
1114 */
1115 public long staticFieldOffset(Field f) {
1116 if (f == null) {
1117 throw new NullPointerException();
1118 }
1119
1120 return staticFieldOffset0(f);
1121 }
1122
1123 /**
1124 * Reports the location of a given static field, in conjunction with {@link
1125 * #staticFieldOffset}.
1126 * <p>Fetch the base "Object", if any, with which static fields of the
1127 * given class can be accessed via methods like {@link #getInt(Object,
1128 * long)}. This value may be null. This value may refer to an object
1129 * which is a "cookie", not guaranteed to be a real Object, and it should
1130 * not be used in any way except as argument to the get and put routines in
1131 * this class.
1132 */
1133 public Object staticFieldBase(Field f) {
1134 if (f == null) {
1135 throw new NullPointerException();
1136 }
1137
1138 return staticFieldBase0(f);
1139 }
1140
1141 /**
1142 * Detects if the given class may need to be initialized. This is often
1143 * needed in conjunction with obtaining the static field base of a
1144 * class.
1145 * @return false only if a call to {@code ensureClassInitialized} would have no effect
1146 */
1147 public boolean shouldBeInitialized(Class<?> c) {
1148 if (c == null) {
1149 throw new NullPointerException();
1150 }
1151
1152 return shouldBeInitialized0(c);
1153 }
1154
1155 /**
1156 * Ensures the given class has been initialized. This is often
1157 * needed in conjunction with obtaining the static field base of a
1158 * class.
1159 */
1160 public void ensureClassInitialized(Class<?> c) {
1161 if (c == null) {
1162 throw new NullPointerException();
1163 }
1164
1165 ensureClassInitialized0(c);
1166 }
1167
1168 /**
1169 * Reports the offset of the first element in the storage allocation of a
1170 * given array class. If {@link #arrayIndexScale} returns a non-zero value
1171 * for the same class, you may use that scale factor, together with this
1172 * base offset, to form new offsets to access elements of arrays of the
1173 * given class.
1174 *
1175 * @see #getInt(Object, long)
1176 * @see #putInt(Object, long, int)
1177 */
1178 public int arrayBaseOffset(Class<?> arrayClass) {
1179 if (arrayClass == null) {
1180 throw new NullPointerException();
1181 }
1182
1183 return arrayBaseOffset0(arrayClass);
1184 }
1185
1186
1187 /** The value of {@code arrayBaseOffset(boolean[].class)} */
1188 public static final int ARRAY_BOOLEAN_BASE_OFFSET
1189 = theUnsafe.arrayBaseOffset(boolean[].class);
1190
1191 /** The value of {@code arrayBaseOffset(byte[].class)} */
1192 public static final int ARRAY_BYTE_BASE_OFFSET
1193 = theUnsafe.arrayBaseOffset(byte[].class);
1194
1195 /** The value of {@code arrayBaseOffset(short[].class)} */
1196 public static final int ARRAY_SHORT_BASE_OFFSET
1197 = theUnsafe.arrayBaseOffset(short[].class);
1198
1199 /** The value of {@code arrayBaseOffset(char[].class)} */
1200 public static final int ARRAY_CHAR_BASE_OFFSET
1201 = theUnsafe.arrayBaseOffset(char[].class);
1202
1203 /** The value of {@code arrayBaseOffset(int[].class)} */
1204 public static final int ARRAY_INT_BASE_OFFSET
1205 = theUnsafe.arrayBaseOffset(int[].class);
1206
1207 /** The value of {@code arrayBaseOffset(long[].class)} */
1208 public static final int ARRAY_LONG_BASE_OFFSET
1209 = theUnsafe.arrayBaseOffset(long[].class);
1210
1211 /** The value of {@code arrayBaseOffset(float[].class)} */
1212 public static final int ARRAY_FLOAT_BASE_OFFSET
1213 = theUnsafe.arrayBaseOffset(float[].class);
1214
1215 /** The value of {@code arrayBaseOffset(double[].class)} */
1216 public static final int ARRAY_DOUBLE_BASE_OFFSET
1217 = theUnsafe.arrayBaseOffset(double[].class);
1218
1219 /** The value of {@code arrayBaseOffset(Object[].class)} */
1220 public static final int ARRAY_OBJECT_BASE_OFFSET
1221 = theUnsafe.arrayBaseOffset(Object[].class);
1222
1223 /**
1224 * Reports the scale factor for addressing elements in the storage
1225 * allocation of a given array class. However, arrays of "narrow" types
1226 * will generally not work properly with accessors like {@link
1227 * #getByte(Object, long)}, so the scale factor for such classes is reported
1228 * as zero.
1229 *
1230 * @see #arrayBaseOffset
1231 * @see #getInt(Object, long)
1232 * @see #putInt(Object, long, int)
1233 */
1234 public int arrayIndexScale(Class<?> arrayClass) {
1235 if (arrayClass == null) {
1236 throw new NullPointerException();
1237 }
1238
1239 return arrayIndexScale0(arrayClass);
1240 }
1241
1242
1243 /** The value of {@code arrayIndexScale(boolean[].class)} */
1244 public static final int ARRAY_BOOLEAN_INDEX_SCALE
1245 = theUnsafe.arrayIndexScale(boolean[].class);
1246
1247 /** The value of {@code arrayIndexScale(byte[].class)} */
1248 public static final int ARRAY_BYTE_INDEX_SCALE
1249 = theUnsafe.arrayIndexScale(byte[].class);
1250
1251 /** The value of {@code arrayIndexScale(short[].class)} */
1252 public static final int ARRAY_SHORT_INDEX_SCALE
1253 = theUnsafe.arrayIndexScale(short[].class);
1254
1255 /** The value of {@code arrayIndexScale(char[].class)} */
1256 public static final int ARRAY_CHAR_INDEX_SCALE
1257 = theUnsafe.arrayIndexScale(char[].class);
1258
1259 /** The value of {@code arrayIndexScale(int[].class)} */
1260 public static final int ARRAY_INT_INDEX_SCALE
1261 = theUnsafe.arrayIndexScale(int[].class);
1262
1263 /** The value of {@code arrayIndexScale(long[].class)} */
1264 public static final int ARRAY_LONG_INDEX_SCALE
1265 = theUnsafe.arrayIndexScale(long[].class);
1266
1267 /** The value of {@code arrayIndexScale(float[].class)} */
1268 public static final int ARRAY_FLOAT_INDEX_SCALE
1269 = theUnsafe.arrayIndexScale(float[].class);
1270
1271 /** The value of {@code arrayIndexScale(double[].class)} */
1272 public static final int ARRAY_DOUBLE_INDEX_SCALE
1273 = theUnsafe.arrayIndexScale(double[].class);
1274
1275 /** The value of {@code arrayIndexScale(Object[].class)} */
1276 public static final int ARRAY_OBJECT_INDEX_SCALE
1277 = theUnsafe.arrayIndexScale(Object[].class);
1278
1279 /**
1280 * Reports the size in bytes of a native pointer, as stored via {@link
1281 * #putAddress}. This value will be either 4 or 8. Note that the sizes of
1282 * other primitive types (as stored in native memory blocks) is determined
1283 * fully by their information content.
1284 */
1285 public int addressSize() {
1286 return ADDRESS_SIZE;
1287 }
1288
1289 /** The value of {@code addressSize()} */
1290 public static final int ADDRESS_SIZE = ADDRESS_SIZE0;
1291
1292 /**
1293 * Reports the size in bytes of a native memory page (whatever that is).
1294 * This value will always be a power of two.
1295 */
1296 public int pageSize() { return PAGE_SIZE; }
1297
1298 /// random trusted operations from JNI:
1299
1300 /**
1301 * Tells the VM to define a class, without security checks. By default, the
1302 * class loader and protection domain come from the caller's class.
1303 */
1304 public Class<?> defineClass(String name, byte[] b, int off, int len,
1305 ClassLoader loader,
1306 ProtectionDomain protectionDomain) {
1307 if (b == null) {
1308 throw new NullPointerException();
1309 }
1310 if (len < 0) {
1311 throw new ArrayIndexOutOfBoundsException();
1312 }
1313
1314 return defineClass0(name, b, off, len, loader, protectionDomain);
1315 }
1316
1317 public native Class<?> defineClass0(String name, byte[] b, int off, int len,
1318 ClassLoader loader,
1319 ProtectionDomain protectionDomain);
1320
1321 /**
1322 * Defines a class but does not make it known to the class loader or system dictionary.
1323 * <p>
1324 * For each CP entry, the corresponding CP patch must either be null or have
1325 * the a format that matches its tag:
1326 * <ul>
1327 * <li>Integer, Long, Float, Double: the corresponding wrapper object type from java.lang
1328 * <li>Utf8: a string (must have suitable syntax if used as signature or name)
1329 * <li>Class: any java.lang.Class object
1330 * <li>String: any object (not just a java.lang.String)
1331 * <li>InterfaceMethodRef: (NYI) a method handle to invoke on that call site's arguments
1332 * </ul>
1333 * @param hostClass context for linkage, access control, protection domain, and class loader
1334 * @param data bytes of a class file
1335 * @param cpPatches where non-null entries exist, they replace corresponding CP entries in data
1336 */
1337 public Class<?> defineAnonymousClass(Class<?> hostClass, byte[] data, Object[] cpPatches) {
1338 if (hostClass == null || data == null) {
1339 throw new NullPointerException();
1340 }
1341 if (hostClass.isArray() || hostClass.isPrimitive()) {
1342 throw new IllegalArgumentException();
1343 }
1344
1345 return defineAnonymousClass0(hostClass, data, cpPatches);
1346 }
1347
1348 /**
1349 * Allocates an instance but does not run any constructor.
1350 * Initializes the class if it has not yet been.
1351 */
1352 @HotSpotIntrinsicCandidate
1353 public native Object allocateInstance(Class<?> cls)
1354 throws InstantiationException;
1355
1356 /**
1357 * Allocates an array of a given type, but does not do zeroing.
1358 * <p>
1359 * This method should only be used in the very rare cases where a high-performance code
1360 * overwrites the destination array completely, and compilers cannot assist in zeroing elimination.
1361 * In an overwhelming majority of cases, a normal Java allocation should be used instead.
1362 * <p>
1363 * Users of this method are <b>required</b> to overwrite the initial (garbage) array contents
1364 * before allowing untrusted code, or code in other threads, to observe the reference
1365 * to the newly allocated array. In addition, the publication of the array reference must be
1366 * safe according to the Java Memory Model requirements.
1367 * <p>
1368 * The safest approach to deal with an uninitialized array is to keep the reference to it in local
1369 * variable at least until the initialization is complete, and then publish it <b>once</b>, either
1370 * by writing it to a <em>volatile</em> field, or storing it into a <em>final</em> field in constructor,
1371 * or issuing a {@link #storeFence} before publishing the reference.
1372 * <p>
1373 * @implnote This method can only allocate primitive arrays, to avoid garbage reference
1374 * elements that could break heap integrity.
1375 *
1376 * @param componentType array component type to allocate
1377 * @param length array size to allocate
1378 * @throws IllegalArgumentException if component type is null, or not a primitive class;
1379 * or the length is negative
1380 */
1381 public Object allocateUninitializedArray(Class<?> componentType, int length) {
1382 if (componentType == null) {
1383 throw new IllegalArgumentException("Component type is null");
1384 }
1385 if (!componentType.isPrimitive()) {
1386 throw new IllegalArgumentException("Component type is not primitive");
1387 }
1388 if (length < 0) {
1389 throw new IllegalArgumentException("Negative length");
1390 }
1391 return allocateUninitializedArray0(componentType, length);
1392 }
1393
1394 @HotSpotIntrinsicCandidate
1395 private Object allocateUninitializedArray0(Class<?> componentType, int length) {
1396 // These fallbacks provide zeroed arrays, but intrinsic is not required to
1397 // return the zeroed arrays.
1398 if (componentType == byte.class) return new byte[length];
1399 if (componentType == boolean.class) return new boolean[length];
1400 if (componentType == short.class) return new short[length];
1401 if (componentType == char.class) return new char[length];
1402 if (componentType == int.class) return new int[length];
1403 if (componentType == float.class) return new float[length];
1404 if (componentType == long.class) return new long[length];
1405 if (componentType == double.class) return new double[length];
1406 return null;
1407 }
1408
1409 /** Throws the exception without telling the verifier. */
1410 public native void throwException(Throwable ee);
1411
1412 /**
1413 * Atomically updates Java variable to {@code x} if it is currently
1414 * holding {@code expected}.
1415 *
1416 * <p>This operation has memory semantics of a {@code volatile} read
1417 * and write. Corresponds to C11 atomic_compare_exchange_strong.
1418 *
1419 * @return {@code true} if successful
1420 */
1421 @HotSpotIntrinsicCandidate
1422 public final native boolean compareAndSetReference(Object o, long offset,
1423 Object expected,
1424 Object x);
1425
1426 private final boolean isInlineType(Object o) {
1427 return o != null && o.getClass().isInlineClass();
1428 }
1429
1430 /*
1431 * For inline type, CAS should do substitutability test as opposed
1432 * to two pointers comparison.
1433 *
1434 * Perhaps we can keep the xxxObject methods for compatibility and
1435 * change the JDK 13 xxxReference method signature freely.
1436 */
1437 public final <V> boolean compareAndSetReference(Object o, long offset,
1438 Class<?> valueType,
1439 V expected,
1440 V x) {
1441 if (valueType.isInlineClass() || isInlineType(expected)) {
1442 synchronized (valueLock) {
1443 Object witness = getReference(o, offset);
1444 if (witness == expected) {
1445 putReference(o, offset, x);
1446 return true;
1447 } else {
1448 return false;
1449 }
1450 }
1451 } else {
1452 return compareAndSetReference(o, offset, expected, x);
1453 }
1454 }
1455
1456 @ForceInline
1457 public final <V> boolean compareAndSetValue(Object o, long offset,
1458 Class<?> valueType,
1459 V expected,
1460 V x) {
1461 synchronized (valueLock) {
1462 Object witness = getValue(o, offset, valueType);
1463 if (witness == expected) {
1464 putValue(o, offset, valueType, x);
1465 return true;
1466 }
1467 else {
1468 return false;
1469 }
1470 }
1471 }
1472
1473 @HotSpotIntrinsicCandidate
1474 public final native Object compareAndExchangeReference(Object o, long offset,
1475 Object expected,
1476 Object x);
1477
1478 public final <V> Object compareAndExchangeReference(Object o, long offset,
1479 Class<?> valueType,
1480 V expected,
1481 V x) {
1482 if (valueType.isInlineClass() || isInlineType(expected)) {
1483 synchronized (valueLock) {
1484 Object witness = getReference(o, offset);
1485 if (witness == expected) {
1486 putReference(o, offset, x);
1487 }
1488 return witness;
1489 }
1490 } else {
1491 return compareAndExchangeReference(o, offset, expected, x);
1492 }
1493 }
1494
1495 @ForceInline
1496 public final <V> Object compareAndExchangeValue(Object o, long offset,
1497 Class<?> valueType,
1498 V expected,
1499 V x) {
1500 synchronized (valueLock) {
1501 Object witness = getValue(o, offset, valueType);
1502 if (witness == expected) {
1503 putValue(o, offset, valueType, x);
1504 }
1505 return witness;
1506 }
1507 }
1508
1509 @HotSpotIntrinsicCandidate
1510 public final Object compareAndExchangeReferenceAcquire(Object o, long offset,
1511 Object expected,
1512 Object x) {
1513 return compareAndExchangeReference(o, offset, expected, x);
1514 }
1515
1516 public final <V> Object compareAndExchangeReferenceAcquire(Object o, long offset,
1517 Class<?> valueType,
1518 V expected,
1519 V x) {
1520 return compareAndExchangeReference(o, offset, valueType, expected, x);
1521 }
1522
1523 @ForceInline
1524 public final <V> Object compareAndExchangeValueAcquire(Object o, long offset,
1525 Class<?> valueType,
1526 V expected,
1527 V x) {
1528 return compareAndExchangeValue(o, offset, valueType, expected, x);
1529 }
1530
1531 @HotSpotIntrinsicCandidate
1532 public final Object compareAndExchangeReferenceRelease(Object o, long offset,
1533 Object expected,
1534 Object x) {
1535 return compareAndExchangeReference(o, offset, expected, x);
1536 }
1537
1538 public final <V> Object compareAndExchangeReferenceRelease(Object o, long offset,
1539 Class<?> valueType,
1540 V expected,
1541 V x) {
1542 return compareAndExchangeReference(o, offset, valueType, expected, x);
1543 }
1544
1545 @ForceInline
1546 public final <V> Object compareAndExchangeValueRelease(Object o, long offset,
1547 Class<?> valueType,
1548 V expected,
1549 V x) {
1550 return compareAndExchangeValue(o, offset, valueType, expected, x);
1551 }
1552
1553 @HotSpotIntrinsicCandidate
1554 public final boolean weakCompareAndSetReferencePlain(Object o, long offset,
1555 Object expected,
1556 Object x) {
1557 return compareAndSetReference(o, offset, expected, x);
1558 }
1559
1560 public final <V> boolean weakCompareAndSetReferencePlain(Object o, long offset,
1561 Class<?> valueType,
1562 V expected,
1563 V x) {
1564 if (valueType.isInlineClass() || isInlineType(expected)) {
1565 return compareAndSetReference(o, offset, valueType, expected, x);
1566 } else {
1567 return weakCompareAndSetReferencePlain(o, offset, expected, x);
1568 }
1569 }
1570
1571 @ForceInline
1572 public final <V> boolean weakCompareAndSetValuePlain(Object o, long offset,
1573 Class<?> valueType,
1574 V expected,
1575 V x) {
1576 return compareAndSetValue(o, offset, valueType, expected, x);
1577 }
1578
1579 @HotSpotIntrinsicCandidate
1580 public final boolean weakCompareAndSetReferenceAcquire(Object o, long offset,
1581 Object expected,
1582 Object x) {
1583 return compareAndSetReference(o, offset, expected, x);
1584 }
1585
1586 public final <V> boolean weakCompareAndSetReferenceAcquire(Object o, long offset,
1587 Class<?> valueType,
1588 V expected,
1589 V x) {
1590 if (valueType.isInlineClass() || isInlineType(expected)) {
1591 return compareAndSetReference(o, offset, valueType, expected, x);
1592 } else {
1593 return weakCompareAndSetReferencePlain(o, offset, expected, x);
1594 }
1595 }
1596
1597 @ForceInline
1598 public final <V> boolean weakCompareAndSetValueAcquire(Object o, long offset,
1599 Class<?> valueType,
1600 V expected,
1601 V x) {
1602 return compareAndSetValue(o, offset, valueType, expected, x);
1603 }
1604
1605 @HotSpotIntrinsicCandidate
1606 public final boolean weakCompareAndSetReferenceRelease(Object o, long offset,
1607 Object expected,
1608 Object x) {
1609 return compareAndSetReference(o, offset, expected, x);
1610 }
1611
1612 public final <V> boolean weakCompareAndSetReferenceRelease(Object o, long offset,
1613 Class<?> valueType,
1614 V expected,
1615 V x) {
1616 if (valueType.isInlineClass() || isInlineType(expected)) {
1617 return compareAndSetReference(o, offset, valueType, expected, x);
1618 } else {
1619 return weakCompareAndSetReferencePlain(o, offset, expected, x);
1620 }
1621 }
1622
1623 @ForceInline
1624 public final <V> boolean weakCompareAndSetValueRelease(Object o, long offset,
1625 Class<?> valueType,
1626 V expected,
1627 V x) {
1628 return compareAndSetValue(o, offset, valueType, expected, x);
1629 }
1630
1631 @HotSpotIntrinsicCandidate
1632 public final boolean weakCompareAndSetReference(Object o, long offset,
1633 Object expected,
1634 Object x) {
1635 return compareAndSetReference(o, offset, expected, x);
1636 }
1637
1638 public final <V> boolean weakCompareAndSetReference(Object o, long offset,
1639 Class<?> valueType,
1640 V expected,
1641 V x) {
1642 if (valueType.isInlineClass() || isInlineType(expected)) {
1643 return compareAndSetReference(o, offset, valueType, expected, x);
1644 } else {
1645 return weakCompareAndSetReferencePlain(o, offset, expected, x);
1646 }
1647 }
1648
1649 @ForceInline
1650 public final <V> boolean weakCompareAndSetValue(Object o, long offset,
1651 Class<?> valueType,
1652 V expected,
1653 V x) {
1654 return compareAndSetValue(o, offset, valueType, expected, x);
1655 }
1656
1657 /**
1658 * Atomically updates Java variable to {@code x} if it is currently
1659 * holding {@code expected}.
1660 *
1661 * <p>This operation has memory semantics of a {@code volatile} read
1662 * and write. Corresponds to C11 atomic_compare_exchange_strong.
1663 *
1664 * @return {@code true} if successful
1665 */
1666 @HotSpotIntrinsicCandidate
1667 public final native boolean compareAndSetInt(Object o, long offset,
1668 int expected,
1669 int x);
1670
1671 @HotSpotIntrinsicCandidate
1672 public final native int compareAndExchangeInt(Object o, long offset,
1673 int expected,
1674 int x);
1675
1676 @HotSpotIntrinsicCandidate
1677 public final int compareAndExchangeIntAcquire(Object o, long offset,
1678 int expected,
1679 int x) {
1680 return compareAndExchangeInt(o, offset, expected, x);
1681 }
1682
1683 @HotSpotIntrinsicCandidate
1684 public final int compareAndExchangeIntRelease(Object o, long offset,
1685 int expected,
1686 int x) {
1687 return compareAndExchangeInt(o, offset, expected, x);
1688 }
1689
1690 @HotSpotIntrinsicCandidate
1691 public final boolean weakCompareAndSetIntPlain(Object o, long offset,
1692 int expected,
1693 int x) {
1694 return compareAndSetInt(o, offset, expected, x);
1695 }
1696
1697 @HotSpotIntrinsicCandidate
1698 public final boolean weakCompareAndSetIntAcquire(Object o, long offset,
1699 int expected,
1700 int x) {
1701 return compareAndSetInt(o, offset, expected, x);
1702 }
1703
1704 @HotSpotIntrinsicCandidate
1705 public final boolean weakCompareAndSetIntRelease(Object o, long offset,
1706 int expected,
1707 int x) {
1708 return compareAndSetInt(o, offset, expected, x);
1709 }
1710
1711 @HotSpotIntrinsicCandidate
1712 public final boolean weakCompareAndSetInt(Object o, long offset,
1713 int expected,
1714 int x) {
1715 return compareAndSetInt(o, offset, expected, x);
1716 }
1717
1718 @HotSpotIntrinsicCandidate
1719 public final byte compareAndExchangeByte(Object o, long offset,
1720 byte expected,
1721 byte x) {
1722 long wordOffset = offset & ~3;
1723 int shift = (int) (offset & 3) << 3;
1724 if (BIG_ENDIAN) {
1725 shift = 24 - shift;
1726 }
1727 int mask = 0xFF << shift;
1728 int maskedExpected = (expected & 0xFF) << shift;
1729 int maskedX = (x & 0xFF) << shift;
1730 int fullWord;
1731 do {
1732 fullWord = getIntVolatile(o, wordOffset);
1733 if ((fullWord & mask) != maskedExpected)
1734 return (byte) ((fullWord & mask) >> shift);
1735 } while (!weakCompareAndSetInt(o, wordOffset,
1736 fullWord, (fullWord & ~mask) | maskedX));
1737 return expected;
1738 }
1739
1740 @HotSpotIntrinsicCandidate
1741 public final boolean compareAndSetByte(Object o, long offset,
1742 byte expected,
1743 byte x) {
1744 return compareAndExchangeByte(o, offset, expected, x) == expected;
1745 }
1746
1747 @HotSpotIntrinsicCandidate
1748 public final boolean weakCompareAndSetByte(Object o, long offset,
1749 byte expected,
1750 byte x) {
1751 return compareAndSetByte(o, offset, expected, x);
1752 }
1753
1754 @HotSpotIntrinsicCandidate
1755 public final boolean weakCompareAndSetByteAcquire(Object o, long offset,
1756 byte expected,
1757 byte x) {
1758 return weakCompareAndSetByte(o, offset, expected, x);
1759 }
1760
1761 @HotSpotIntrinsicCandidate
1762 public final boolean weakCompareAndSetByteRelease(Object o, long offset,
1763 byte expected,
1764 byte x) {
1765 return weakCompareAndSetByte(o, offset, expected, x);
1766 }
1767
1768 @HotSpotIntrinsicCandidate
1769 public final boolean weakCompareAndSetBytePlain(Object o, long offset,
1770 byte expected,
1771 byte x) {
1772 return weakCompareAndSetByte(o, offset, expected, x);
1773 }
1774
1775 @HotSpotIntrinsicCandidate
1776 public final byte compareAndExchangeByteAcquire(Object o, long offset,
1777 byte expected,
1778 byte x) {
1779 return compareAndExchangeByte(o, offset, expected, x);
1780 }
1781
1782 @HotSpotIntrinsicCandidate
1783 public final byte compareAndExchangeByteRelease(Object o, long offset,
1784 byte expected,
1785 byte x) {
1786 return compareAndExchangeByte(o, offset, expected, x);
1787 }
1788
1789 @HotSpotIntrinsicCandidate
1790 public final short compareAndExchangeShort(Object o, long offset,
1791 short expected,
1792 short x) {
1793 if ((offset & 3) == 3) {
1794 throw new IllegalArgumentException("Update spans the word, not supported");
1795 }
1796 long wordOffset = offset & ~3;
1797 int shift = (int) (offset & 3) << 3;
1798 if (BIG_ENDIAN) {
1799 shift = 16 - shift;
1800 }
1801 int mask = 0xFFFF << shift;
1802 int maskedExpected = (expected & 0xFFFF) << shift;
1803 int maskedX = (x & 0xFFFF) << shift;
1804 int fullWord;
1805 do {
1806 fullWord = getIntVolatile(o, wordOffset);
1807 if ((fullWord & mask) != maskedExpected) {
1808 return (short) ((fullWord & mask) >> shift);
1809 }
1810 } while (!weakCompareAndSetInt(o, wordOffset,
1811 fullWord, (fullWord & ~mask) | maskedX));
1812 return expected;
1813 }
1814
1815 @HotSpotIntrinsicCandidate
1816 public final boolean compareAndSetShort(Object o, long offset,
1817 short expected,
1818 short x) {
1819 return compareAndExchangeShort(o, offset, expected, x) == expected;
1820 }
1821
1822 @HotSpotIntrinsicCandidate
1823 public final boolean weakCompareAndSetShort(Object o, long offset,
1824 short expected,
1825 short x) {
1826 return compareAndSetShort(o, offset, expected, x);
1827 }
1828
1829 @HotSpotIntrinsicCandidate
1830 public final boolean weakCompareAndSetShortAcquire(Object o, long offset,
1831 short expected,
1832 short x) {
1833 return weakCompareAndSetShort(o, offset, expected, x);
1834 }
1835
1836 @HotSpotIntrinsicCandidate
1837 public final boolean weakCompareAndSetShortRelease(Object o, long offset,
1838 short expected,
1839 short x) {
1840 return weakCompareAndSetShort(o, offset, expected, x);
1841 }
1842
1843 @HotSpotIntrinsicCandidate
1844 public final boolean weakCompareAndSetShortPlain(Object o, long offset,
1845 short expected,
1846 short x) {
1847 return weakCompareAndSetShort(o, offset, expected, x);
1848 }
1849
1850
1851 @HotSpotIntrinsicCandidate
1852 public final short compareAndExchangeShortAcquire(Object o, long offset,
1853 short expected,
1854 short x) {
1855 return compareAndExchangeShort(o, offset, expected, x);
1856 }
1857
1858 @HotSpotIntrinsicCandidate
1859 public final short compareAndExchangeShortRelease(Object o, long offset,
1860 short expected,
1861 short x) {
1862 return compareAndExchangeShort(o, offset, expected, x);
1863 }
1864
1865 @ForceInline
1866 private char s2c(short s) {
1867 return (char) s;
1868 }
1869
1870 @ForceInline
1871 private short c2s(char s) {
1872 return (short) s;
1873 }
1874
1875 @ForceInline
1876 public final boolean compareAndSetChar(Object o, long offset,
1877 char expected,
1878 char x) {
1879 return compareAndSetShort(o, offset, c2s(expected), c2s(x));
1880 }
1881
1882 @ForceInline
1883 public final char compareAndExchangeChar(Object o, long offset,
1884 char expected,
1885 char x) {
1886 return s2c(compareAndExchangeShort(o, offset, c2s(expected), c2s(x)));
1887 }
1888
1889 @ForceInline
1890 public final char compareAndExchangeCharAcquire(Object o, long offset,
1891 char expected,
1892 char x) {
1893 return s2c(compareAndExchangeShortAcquire(o, offset, c2s(expected), c2s(x)));
1894 }
1895
1896 @ForceInline
1897 public final char compareAndExchangeCharRelease(Object o, long offset,
1898 char expected,
1899 char x) {
1900 return s2c(compareAndExchangeShortRelease(o, offset, c2s(expected), c2s(x)));
1901 }
1902
1903 @ForceInline
1904 public final boolean weakCompareAndSetChar(Object o, long offset,
1905 char expected,
1906 char x) {
1907 return weakCompareAndSetShort(o, offset, c2s(expected), c2s(x));
1908 }
1909
1910 @ForceInline
1911 public final boolean weakCompareAndSetCharAcquire(Object o, long offset,
1912 char expected,
1913 char x) {
1914 return weakCompareAndSetShortAcquire(o, offset, c2s(expected), c2s(x));
1915 }
1916
1917 @ForceInline
1918 public final boolean weakCompareAndSetCharRelease(Object o, long offset,
1919 char expected,
1920 char x) {
1921 return weakCompareAndSetShortRelease(o, offset, c2s(expected), c2s(x));
1922 }
1923
1924 @ForceInline
1925 public final boolean weakCompareAndSetCharPlain(Object o, long offset,
1926 char expected,
1927 char x) {
1928 return weakCompareAndSetShortPlain(o, offset, c2s(expected), c2s(x));
1929 }
1930
1931 /**
1932 * The JVM converts integral values to boolean values using two
1933 * different conventions, byte testing against zero and truncation
1934 * to least-significant bit.
1935 *
1936 * <p>The JNI documents specify that, at least for returning
1937 * values from native methods, a Java boolean value is converted
1938 * to the value-set 0..1 by first truncating to a byte (0..255 or
1939 * maybe -128..127) and then testing against zero. Thus, Java
1940 * booleans in non-Java data structures are by convention
1941 * represented as 8-bit containers containing either zero (for
1942 * false) or any non-zero value (for true).
1943 *
1944 * <p>Java booleans in the heap are also stored in bytes, but are
1945 * strongly normalized to the value-set 0..1 (i.e., they are
1946 * truncated to the least-significant bit).
1947 *
1948 * <p>The main reason for having different conventions for
1949 * conversion is performance: Truncation to the least-significant
1950 * bit can be usually implemented with fewer (machine)
1951 * instructions than byte testing against zero.
1952 *
1953 * <p>A number of Unsafe methods load boolean values from the heap
1954 * as bytes. Unsafe converts those values according to the JNI
1955 * rules (i.e, using the "testing against zero" convention). The
1956 * method {@code byte2bool} implements that conversion.
1957 *
1958 * @param b the byte to be converted to boolean
1959 * @return the result of the conversion
1960 */
1961 @ForceInline
1962 private boolean byte2bool(byte b) {
1963 return b != 0;
1964 }
1965
1966 /**
1967 * Convert a boolean value to a byte. The return value is strongly
1968 * normalized to the value-set 0..1 (i.e., the value is truncated
1969 * to the least-significant bit). See {@link #byte2bool(byte)} for
1970 * more details on conversion conventions.
1971 *
1972 * @param b the boolean to be converted to byte (and then normalized)
1973 * @return the result of the conversion
1974 */
1975 @ForceInline
1976 private byte bool2byte(boolean b) {
1977 return b ? (byte)1 : (byte)0;
1978 }
1979
1980 @ForceInline
1981 public final boolean compareAndSetBoolean(Object o, long offset,
1982 boolean expected,
1983 boolean x) {
1984 return compareAndSetByte(o, offset, bool2byte(expected), bool2byte(x));
1985 }
1986
1987 @ForceInline
1988 public final boolean compareAndExchangeBoolean(Object o, long offset,
1989 boolean expected,
1990 boolean x) {
1991 return byte2bool(compareAndExchangeByte(o, offset, bool2byte(expected), bool2byte(x)));
1992 }
1993
1994 @ForceInline
1995 public final boolean compareAndExchangeBooleanAcquire(Object o, long offset,
1996 boolean expected,
1997 boolean x) {
1998 return byte2bool(compareAndExchangeByteAcquire(o, offset, bool2byte(expected), bool2byte(x)));
1999 }
2000
2001 @ForceInline
2002 public final boolean compareAndExchangeBooleanRelease(Object o, long offset,
2003 boolean expected,
2004 boolean x) {
2005 return byte2bool(compareAndExchangeByteRelease(o, offset, bool2byte(expected), bool2byte(x)));
2006 }
2007
2008 @ForceInline
2009 public final boolean weakCompareAndSetBoolean(Object o, long offset,
2010 boolean expected,
2011 boolean x) {
2012 return weakCompareAndSetByte(o, offset, bool2byte(expected), bool2byte(x));
2013 }
2014
2015 @ForceInline
2016 public final boolean weakCompareAndSetBooleanAcquire(Object o, long offset,
2017 boolean expected,
2018 boolean x) {
2019 return weakCompareAndSetByteAcquire(o, offset, bool2byte(expected), bool2byte(x));
2020 }
2021
2022 @ForceInline
2023 public final boolean weakCompareAndSetBooleanRelease(Object o, long offset,
2024 boolean expected,
2025 boolean x) {
2026 return weakCompareAndSetByteRelease(o, offset, bool2byte(expected), bool2byte(x));
2027 }
2028
2029 @ForceInline
2030 public final boolean weakCompareAndSetBooleanPlain(Object o, long offset,
2031 boolean expected,
2032 boolean x) {
2033 return weakCompareAndSetBytePlain(o, offset, bool2byte(expected), bool2byte(x));
2034 }
2035
2036 /**
2037 * Atomically updates Java variable to {@code x} if it is currently
2038 * holding {@code expected}.
2039 *
2040 * <p>This operation has memory semantics of a {@code volatile} read
2041 * and write. Corresponds to C11 atomic_compare_exchange_strong.
2042 *
2043 * @return {@code true} if successful
2044 */
2045 @ForceInline
2046 public final boolean compareAndSetFloat(Object o, long offset,
2047 float expected,
2048 float x) {
2049 return compareAndSetInt(o, offset,
2050 Float.floatToRawIntBits(expected),
2051 Float.floatToRawIntBits(x));
2052 }
2053
2054 @ForceInline
2055 public final float compareAndExchangeFloat(Object o, long offset,
2056 float expected,
2057 float x) {
2058 int w = compareAndExchangeInt(o, offset,
2059 Float.floatToRawIntBits(expected),
2060 Float.floatToRawIntBits(x));
2061 return Float.intBitsToFloat(w);
2062 }
2063
2064 @ForceInline
2065 public final float compareAndExchangeFloatAcquire(Object o, long offset,
2066 float expected,
2067 float x) {
2068 int w = compareAndExchangeIntAcquire(o, offset,
2069 Float.floatToRawIntBits(expected),
2070 Float.floatToRawIntBits(x));
2071 return Float.intBitsToFloat(w);
2072 }
2073
2074 @ForceInline
2075 public final float compareAndExchangeFloatRelease(Object o, long offset,
2076 float expected,
2077 float x) {
2078 int w = compareAndExchangeIntRelease(o, offset,
2079 Float.floatToRawIntBits(expected),
2080 Float.floatToRawIntBits(x));
2081 return Float.intBitsToFloat(w);
2082 }
2083
2084 @ForceInline
2085 public final boolean weakCompareAndSetFloatPlain(Object o, long offset,
2086 float expected,
2087 float x) {
2088 return weakCompareAndSetIntPlain(o, offset,
2089 Float.floatToRawIntBits(expected),
2090 Float.floatToRawIntBits(x));
2091 }
2092
2093 @ForceInline
2094 public final boolean weakCompareAndSetFloatAcquire(Object o, long offset,
2095 float expected,
2096 float x) {
2097 return weakCompareAndSetIntAcquire(o, offset,
2098 Float.floatToRawIntBits(expected),
2099 Float.floatToRawIntBits(x));
2100 }
2101
2102 @ForceInline
2103 public final boolean weakCompareAndSetFloatRelease(Object o, long offset,
2104 float expected,
2105 float x) {
2106 return weakCompareAndSetIntRelease(o, offset,
2107 Float.floatToRawIntBits(expected),
2108 Float.floatToRawIntBits(x));
2109 }
2110
2111 @ForceInline
2112 public final boolean weakCompareAndSetFloat(Object o, long offset,
2113 float expected,
2114 float x) {
2115 return weakCompareAndSetInt(o, offset,
2116 Float.floatToRawIntBits(expected),
2117 Float.floatToRawIntBits(x));
2118 }
2119
2120 /**
2121 * Atomically updates Java variable to {@code x} if it is currently
2122 * holding {@code expected}.
2123 *
2124 * <p>This operation has memory semantics of a {@code volatile} read
2125 * and write. Corresponds to C11 atomic_compare_exchange_strong.
2126 *
2127 * @return {@code true} if successful
2128 */
2129 @ForceInline
2130 public final boolean compareAndSetDouble(Object o, long offset,
2131 double expected,
2132 double x) {
2133 return compareAndSetLong(o, offset,
2134 Double.doubleToRawLongBits(expected),
2135 Double.doubleToRawLongBits(x));
2136 }
2137
2138 @ForceInline
2139 public final double compareAndExchangeDouble(Object o, long offset,
2140 double expected,
2141 double x) {
2142 long w = compareAndExchangeLong(o, offset,
2143 Double.doubleToRawLongBits(expected),
2144 Double.doubleToRawLongBits(x));
2145 return Double.longBitsToDouble(w);
2146 }
2147
2148 @ForceInline
2149 public final double compareAndExchangeDoubleAcquire(Object o, long offset,
2150 double expected,
2151 double x) {
2152 long w = compareAndExchangeLongAcquire(o, offset,
2153 Double.doubleToRawLongBits(expected),
2154 Double.doubleToRawLongBits(x));
2155 return Double.longBitsToDouble(w);
2156 }
2157
2158 @ForceInline
2159 public final double compareAndExchangeDoubleRelease(Object o, long offset,
2160 double expected,
2161 double x) {
2162 long w = compareAndExchangeLongRelease(o, offset,
2163 Double.doubleToRawLongBits(expected),
2164 Double.doubleToRawLongBits(x));
2165 return Double.longBitsToDouble(w);
2166 }
2167
2168 @ForceInline
2169 public final boolean weakCompareAndSetDoublePlain(Object o, long offset,
2170 double expected,
2171 double x) {
2172 return weakCompareAndSetLongPlain(o, offset,
2173 Double.doubleToRawLongBits(expected),
2174 Double.doubleToRawLongBits(x));
2175 }
2176
2177 @ForceInline
2178 public final boolean weakCompareAndSetDoubleAcquire(Object o, long offset,
2179 double expected,
2180 double x) {
2181 return weakCompareAndSetLongAcquire(o, offset,
2182 Double.doubleToRawLongBits(expected),
2183 Double.doubleToRawLongBits(x));
2184 }
2185
2186 @ForceInline
2187 public final boolean weakCompareAndSetDoubleRelease(Object o, long offset,
2188 double expected,
2189 double x) {
2190 return weakCompareAndSetLongRelease(o, offset,
2191 Double.doubleToRawLongBits(expected),
2192 Double.doubleToRawLongBits(x));
2193 }
2194
2195 @ForceInline
2196 public final boolean weakCompareAndSetDouble(Object o, long offset,
2197 double expected,
2198 double x) {
2199 return weakCompareAndSetLong(o, offset,
2200 Double.doubleToRawLongBits(expected),
2201 Double.doubleToRawLongBits(x));
2202 }
2203
2204 /**
2205 * Atomically updates Java variable to {@code x} if it is currently
2206 * holding {@code expected}.
2207 *
2208 * <p>This operation has memory semantics of a {@code volatile} read
2209 * and write. Corresponds to C11 atomic_compare_exchange_strong.
2210 *
2211 * @return {@code true} if successful
2212 */
2213 @HotSpotIntrinsicCandidate
2214 public final native boolean compareAndSetLong(Object o, long offset,
2215 long expected,
2216 long x);
2217
2218 @HotSpotIntrinsicCandidate
2219 public final native long compareAndExchangeLong(Object o, long offset,
2220 long expected,
2221 long x);
2222
2223 @HotSpotIntrinsicCandidate
2224 public final long compareAndExchangeLongAcquire(Object o, long offset,
2225 long expected,
2226 long x) {
2227 return compareAndExchangeLong(o, offset, expected, x);
2228 }
2229
2230 @HotSpotIntrinsicCandidate
2231 public final long compareAndExchangeLongRelease(Object o, long offset,
2232 long expected,
2233 long x) {
2234 return compareAndExchangeLong(o, offset, expected, x);
2235 }
2236
2237 @HotSpotIntrinsicCandidate
2238 public final boolean weakCompareAndSetLongPlain(Object o, long offset,
2239 long expected,
2240 long x) {
2241 return compareAndSetLong(o, offset, expected, x);
2242 }
2243
2244 @HotSpotIntrinsicCandidate
2245 public final boolean weakCompareAndSetLongAcquire(Object o, long offset,
2246 long expected,
2247 long x) {
2248 return compareAndSetLong(o, offset, expected, x);
2249 }
2250
2251 @HotSpotIntrinsicCandidate
2252 public final boolean weakCompareAndSetLongRelease(Object o, long offset,
2253 long expected,
2254 long x) {
2255 return compareAndSetLong(o, offset, expected, x);
2256 }
2257
2258 @HotSpotIntrinsicCandidate
2259 public final boolean weakCompareAndSetLong(Object o, long offset,
2260 long expected,
2261 long x) {
2262 return compareAndSetLong(o, offset, expected, x);
2263 }
2264
2265 /**
2266 * Fetches a reference value from a given Java variable, with volatile
2267 * load semantics. Otherwise identical to {@link #getReference(Object, long)}
2268 */
2269 @HotSpotIntrinsicCandidate
2270 public native Object getReferenceVolatile(Object o, long offset);
2271
2272 /**
2273 * Global lock for atomic and volatile strength access to any value of
2274 * an inline type. This is a temporary workaround until better localized
2275 * atomic access mechanisms are supported for inline types.
2276 */
2277 private static final Object valueLock = new Object();
2278
2279 public final <V> Object getValueVolatile(Object base, long offset, Class<?> valueType) {
2280 synchronized (valueLock) {
2281 return getValue(base, offset, valueType);
2282 }
2283 }
2284
2285 /**
2286 * Stores a reference value into a given Java variable, with
2287 * volatile store semantics. Otherwise identical to {@link #putReference(Object, long, Object)}
2288 */
2289 @HotSpotIntrinsicCandidate
2290 public native void putReferenceVolatile(Object o, long offset, Object x);
2291
2292 public final <V> void putValueVolatile(Object o, long offset, Class<?> valueType, V x) {
2293 synchronized (valueLock) {
2294 putValue(o, offset, valueType, x);
2295 }
2296 }
2297
2298 /** Volatile version of {@link #getInt(Object, long)} */
2299 @HotSpotIntrinsicCandidate
2300 public native int getIntVolatile(Object o, long offset);
2301
2302 /** Volatile version of {@link #putInt(Object, long, int)} */
2303 @HotSpotIntrinsicCandidate
2304 public native void putIntVolatile(Object o, long offset, int x);
2305
2306 /** Volatile version of {@link #getBoolean(Object, long)} */
2307 @HotSpotIntrinsicCandidate
2308 public native boolean getBooleanVolatile(Object o, long offset);
2309
2310 /** Volatile version of {@link #putBoolean(Object, long, boolean)} */
2311 @HotSpotIntrinsicCandidate
2312 public native void putBooleanVolatile(Object o, long offset, boolean x);
2313
2314 /** Volatile version of {@link #getByte(Object, long)} */
2315 @HotSpotIntrinsicCandidate
2316 public native byte getByteVolatile(Object o, long offset);
2317
2318 /** Volatile version of {@link #putByte(Object, long, byte)} */
2319 @HotSpotIntrinsicCandidate
2320 public native void putByteVolatile(Object o, long offset, byte x);
2321
2322 /** Volatile version of {@link #getShort(Object, long)} */
2323 @HotSpotIntrinsicCandidate
2324 public native short getShortVolatile(Object o, long offset);
2325
2326 /** Volatile version of {@link #putShort(Object, long, short)} */
2327 @HotSpotIntrinsicCandidate
2328 public native void putShortVolatile(Object o, long offset, short x);
2329
2330 /** Volatile version of {@link #getChar(Object, long)} */
2331 @HotSpotIntrinsicCandidate
2332 public native char getCharVolatile(Object o, long offset);
2333
2334 /** Volatile version of {@link #putChar(Object, long, char)} */
2335 @HotSpotIntrinsicCandidate
2336 public native void putCharVolatile(Object o, long offset, char x);
2337
2338 /** Volatile version of {@link #getLong(Object, long)} */
2339 @HotSpotIntrinsicCandidate
2340 public native long getLongVolatile(Object o, long offset);
2341
2342 /** Volatile version of {@link #putLong(Object, long, long)} */
2343 @HotSpotIntrinsicCandidate
2344 public native void putLongVolatile(Object o, long offset, long x);
2345
2346 /** Volatile version of {@link #getFloat(Object, long)} */
2347 @HotSpotIntrinsicCandidate
2348 public native float getFloatVolatile(Object o, long offset);
2349
2350 /** Volatile version of {@link #putFloat(Object, long, float)} */
2351 @HotSpotIntrinsicCandidate
2352 public native void putFloatVolatile(Object o, long offset, float x);
2353
2354 /** Volatile version of {@link #getDouble(Object, long)} */
2355 @HotSpotIntrinsicCandidate
2356 public native double getDoubleVolatile(Object o, long offset);
2357
2358 /** Volatile version of {@link #putDouble(Object, long, double)} */
2359 @HotSpotIntrinsicCandidate
2360 public native void putDoubleVolatile(Object o, long offset, double x);
2361
2362
2363
2364 /** Acquire version of {@link #getReferenceVolatile(Object, long)} */
2365 @HotSpotIntrinsicCandidate
2366 public final Object getReferenceAcquire(Object o, long offset) {
2367 return getReferenceVolatile(o, offset);
2368 }
2369
2370 public final <V> Object getValueAcquire(Object base, long offset, Class<?> valueType) {
2371 return getValueVolatile(base, offset, valueType);
2372 }
2373
2374 /** Acquire version of {@link #getBooleanVolatile(Object, long)} */
2375 @HotSpotIntrinsicCandidate
2376 public final boolean getBooleanAcquire(Object o, long offset) {
2377 return getBooleanVolatile(o, offset);
2378 }
2379
2380 /** Acquire version of {@link #getByteVolatile(Object, long)} */
2381 @HotSpotIntrinsicCandidate
2382 public final byte getByteAcquire(Object o, long offset) {
2383 return getByteVolatile(o, offset);
2384 }
2385
2386 /** Acquire version of {@link #getShortVolatile(Object, long)} */
2387 @HotSpotIntrinsicCandidate
2388 public final short getShortAcquire(Object o, long offset) {
2389 return getShortVolatile(o, offset);
2390 }
2391
2392 /** Acquire version of {@link #getCharVolatile(Object, long)} */
2393 @HotSpotIntrinsicCandidate
2394 public final char getCharAcquire(Object o, long offset) {
2395 return getCharVolatile(o, offset);
2396 }
2397
2398 /** Acquire version of {@link #getIntVolatile(Object, long)} */
2399 @HotSpotIntrinsicCandidate
2400 public final int getIntAcquire(Object o, long offset) {
2401 return getIntVolatile(o, offset);
2402 }
2403
2404 /** Acquire version of {@link #getFloatVolatile(Object, long)} */
2405 @HotSpotIntrinsicCandidate
2406 public final float getFloatAcquire(Object o, long offset) {
2407 return getFloatVolatile(o, offset);
2408 }
2409
2410 /** Acquire version of {@link #getLongVolatile(Object, long)} */
2411 @HotSpotIntrinsicCandidate
2412 public final long getLongAcquire(Object o, long offset) {
2413 return getLongVolatile(o, offset);
2414 }
2415
2416 /** Acquire version of {@link #getDoubleVolatile(Object, long)} */
2417 @HotSpotIntrinsicCandidate
2418 public final double getDoubleAcquire(Object o, long offset) {
2419 return getDoubleVolatile(o, offset);
2420 }
2421
2422 /*
2423 * Versions of {@link #putReferenceVolatile(Object, long, Object)}
2424 * that do not guarantee immediate visibility of the store to
2425 * other threads. This method is generally only useful if the
2426 * underlying field is a Java volatile (or if an array cell, one
2427 * that is otherwise only accessed using volatile accesses).
2428 *
2429 * Corresponds to C11 atomic_store_explicit(..., memory_order_release).
2430 */
2431
2432 /** Release version of {@link #putReferenceVolatile(Object, long, Object)} */
2433 @HotSpotIntrinsicCandidate
2434 public final void putReferenceRelease(Object o, long offset, Object x) {
2435 putReferenceVolatile(o, offset, x);
2436 }
2437
2438 public final <V> void putValueRelease(Object o, long offset, Class<?> valueType, V x) {
2439 putValueVolatile(o, offset, valueType, x);
2440 }
2441
2442 /** Release version of {@link #putBooleanVolatile(Object, long, boolean)} */
2443 @HotSpotIntrinsicCandidate
2444 public final void putBooleanRelease(Object o, long offset, boolean x) {
2445 putBooleanVolatile(o, offset, x);
2446 }
2447
2448 /** Release version of {@link #putByteVolatile(Object, long, byte)} */
2449 @HotSpotIntrinsicCandidate
2450 public final void putByteRelease(Object o, long offset, byte x) {
2451 putByteVolatile(o, offset, x);
2452 }
2453
2454 /** Release version of {@link #putShortVolatile(Object, long, short)} */
2455 @HotSpotIntrinsicCandidate
2456 public final void putShortRelease(Object o, long offset, short x) {
2457 putShortVolatile(o, offset, x);
2458 }
2459
2460 /** Release version of {@link #putCharVolatile(Object, long, char)} */
2461 @HotSpotIntrinsicCandidate
2462 public final void putCharRelease(Object o, long offset, char x) {
2463 putCharVolatile(o, offset, x);
2464 }
2465
2466 /** Release version of {@link #putIntVolatile(Object, long, int)} */
2467 @HotSpotIntrinsicCandidate
2468 public final void putIntRelease(Object o, long offset, int x) {
2469 putIntVolatile(o, offset, x);
2470 }
2471
2472 /** Release version of {@link #putFloatVolatile(Object, long, float)} */
2473 @HotSpotIntrinsicCandidate
2474 public final void putFloatRelease(Object o, long offset, float x) {
2475 putFloatVolatile(o, offset, x);
2476 }
2477
2478 /** Release version of {@link #putLongVolatile(Object, long, long)} */
2479 @HotSpotIntrinsicCandidate
2480 public final void putLongRelease(Object o, long offset, long x) {
2481 putLongVolatile(o, offset, x);
2482 }
2483
2484 /** Release version of {@link #putDoubleVolatile(Object, long, double)} */
2485 @HotSpotIntrinsicCandidate
2486 public final void putDoubleRelease(Object o, long offset, double x) {
2487 putDoubleVolatile(o, offset, x);
2488 }
2489
2490 // ------------------------------ Opaque --------------------------------------
2491
2492 /** Opaque version of {@link #getReferenceVolatile(Object, long)} */
2493 @HotSpotIntrinsicCandidate
2494 public final Object getReferenceOpaque(Object o, long offset) {
2495 return getReferenceVolatile(o, offset);
2496 }
2497
2498 public final <V> Object getValueOpaque(Object base, long offset, Class<?> valueType) {
2499 return getValueVolatile(base, offset, valueType);
2500 }
2501
2502 /** Opaque version of {@link #getBooleanVolatile(Object, long)} */
2503 @HotSpotIntrinsicCandidate
2504 public final boolean getBooleanOpaque(Object o, long offset) {
2505 return getBooleanVolatile(o, offset);
2506 }
2507
2508 /** Opaque version of {@link #getByteVolatile(Object, long)} */
2509 @HotSpotIntrinsicCandidate
2510 public final byte getByteOpaque(Object o, long offset) {
2511 return getByteVolatile(o, offset);
2512 }
2513
2514 /** Opaque version of {@link #getShortVolatile(Object, long)} */
2515 @HotSpotIntrinsicCandidate
2516 public final short getShortOpaque(Object o, long offset) {
2517 return getShortVolatile(o, offset);
2518 }
2519
2520 /** Opaque version of {@link #getCharVolatile(Object, long)} */
2521 @HotSpotIntrinsicCandidate
2522 public final char getCharOpaque(Object o, long offset) {
2523 return getCharVolatile(o, offset);
2524 }
2525
2526 /** Opaque version of {@link #getIntVolatile(Object, long)} */
2527 @HotSpotIntrinsicCandidate
2528 public final int getIntOpaque(Object o, long offset) {
2529 return getIntVolatile(o, offset);
2530 }
2531
2532 /** Opaque version of {@link #getFloatVolatile(Object, long)} */
2533 @HotSpotIntrinsicCandidate
2534 public final float getFloatOpaque(Object o, long offset) {
2535 return getFloatVolatile(o, offset);
2536 }
2537
2538 /** Opaque version of {@link #getLongVolatile(Object, long)} */
2539 @HotSpotIntrinsicCandidate
2540 public final long getLongOpaque(Object o, long offset) {
2541 return getLongVolatile(o, offset);
2542 }
2543
2544 /** Opaque version of {@link #getDoubleVolatile(Object, long)} */
2545 @HotSpotIntrinsicCandidate
2546 public final double getDoubleOpaque(Object o, long offset) {
2547 return getDoubleVolatile(o, offset);
2548 }
2549
2550 /** Opaque version of {@link #putReferenceVolatile(Object, long, Object)} */
2551 @HotSpotIntrinsicCandidate
2552 public final void putReferenceOpaque(Object o, long offset, Object x) {
2553 putReferenceVolatile(o, offset, x);
2554 }
2555
2556 public final <V> void putValueOpaque(Object o, long offset, Class<?> valueType, V x) {
2557 putValueVolatile(o, offset, valueType, x);
2558 }
2559
2560 /** Opaque version of {@link #putBooleanVolatile(Object, long, boolean)} */
2561 @HotSpotIntrinsicCandidate
2562 public final void putBooleanOpaque(Object o, long offset, boolean x) {
2563 putBooleanVolatile(o, offset, x);
2564 }
2565
2566 /** Opaque version of {@link #putByteVolatile(Object, long, byte)} */
2567 @HotSpotIntrinsicCandidate
2568 public final void putByteOpaque(Object o, long offset, byte x) {
2569 putByteVolatile(o, offset, x);
2570 }
2571
2572 /** Opaque version of {@link #putShortVolatile(Object, long, short)} */
2573 @HotSpotIntrinsicCandidate
2574 public final void putShortOpaque(Object o, long offset, short x) {
2575 putShortVolatile(o, offset, x);
2576 }
2577
2578 /** Opaque version of {@link #putCharVolatile(Object, long, char)} */
2579 @HotSpotIntrinsicCandidate
2580 public final void putCharOpaque(Object o, long offset, char x) {
2581 putCharVolatile(o, offset, x);
2582 }
2583
2584 /** Opaque version of {@link #putIntVolatile(Object, long, int)} */
2585 @HotSpotIntrinsicCandidate
2586 public final void putIntOpaque(Object o, long offset, int x) {
2587 putIntVolatile(o, offset, x);
2588 }
2589
2590 /** Opaque version of {@link #putFloatVolatile(Object, long, float)} */
2591 @HotSpotIntrinsicCandidate
2592 public final void putFloatOpaque(Object o, long offset, float x) {
2593 putFloatVolatile(o, offset, x);
2594 }
2595
2596 /** Opaque version of {@link #putLongVolatile(Object, long, long)} */
2597 @HotSpotIntrinsicCandidate
2598 public final void putLongOpaque(Object o, long offset, long x) {
2599 putLongVolatile(o, offset, x);
2600 }
2601
2602 /** Opaque version of {@link #putDoubleVolatile(Object, long, double)} */
2603 @HotSpotIntrinsicCandidate
2604 public final void putDoubleOpaque(Object o, long offset, double x) {
2605 putDoubleVolatile(o, offset, x);
2606 }
2607
2608 /**
2609 * Unblocks the given thread blocked on {@code park}, or, if it is
2610 * not blocked, causes the subsequent call to {@code park} not to
2611 * block. Note: this operation is "unsafe" solely because the
2612 * caller must somehow ensure that the thread has not been
2613 * destroyed. Nothing special is usually required to ensure this
2614 * when called from Java (in which there will ordinarily be a live
2615 * reference to the thread) but this is not nearly-automatically
2616 * so when calling from native code.
2617 *
2618 * @param thread the thread to unpark.
2619 */
2620 @HotSpotIntrinsicCandidate
2621 public native void unpark(Object thread);
2622
2623 /**
2624 * Blocks current thread, returning when a balancing
2625 * {@code unpark} occurs, or a balancing {@code unpark} has
2626 * already occurred, or the thread is interrupted, or, if not
2627 * absolute and time is not zero, the given time nanoseconds have
2628 * elapsed, or if absolute, the given deadline in milliseconds
2629 * since Epoch has passed, or spuriously (i.e., returning for no
2630 * "reason"). Note: This operation is in the Unsafe class only
2631 * because {@code unpark} is, so it would be strange to place it
2632 * elsewhere.
2633 */
2634 @HotSpotIntrinsicCandidate
2635 public native void park(boolean isAbsolute, long time);
2636
2637 /**
2638 * Gets the load average in the system run queue assigned
2639 * to the available processors averaged over various periods of time.
2640 * This method retrieves the given {@code nelem} samples and
2641 * assigns to the elements of the given {@code loadavg} array.
2642 * The system imposes a maximum of 3 samples, representing
2643 * averages over the last 1, 5, and 15 minutes, respectively.
2644 *
2645 * @param loadavg an array of double of size nelems
2646 * @param nelems the number of samples to be retrieved and
2647 * must be 1 to 3.
2648 *
2649 * @return the number of samples actually retrieved; or -1
2650 * if the load average is unobtainable.
2651 */
2652 public int getLoadAverage(double[] loadavg, int nelems) {
2653 if (nelems < 0 || nelems > 3 || nelems > loadavg.length) {
2654 throw new ArrayIndexOutOfBoundsException();
2655 }
2656
2657 return getLoadAverage0(loadavg, nelems);
2658 }
2659
2660 // The following contain CAS-based Java implementations used on
2661 // platforms not supporting native instructions
2662
2663 /**
2664 * Atomically adds the given value to the current value of a field
2665 * or array element within the given object {@code o}
2666 * at the given {@code offset}.
2667 *
2668 * @param o object/array to update the field/element in
2669 * @param offset field/element offset
2670 * @param delta the value to add
2671 * @return the previous value
2672 * @since 1.8
2673 */
2674 @HotSpotIntrinsicCandidate
2675 public final int getAndAddInt(Object o, long offset, int delta) {
2676 int v;
2677 do {
2678 v = getIntVolatile(o, offset);
2679 } while (!weakCompareAndSetInt(o, offset, v, v + delta));
2680 return v;
2681 }
2682
2683 @ForceInline
2684 public final int getAndAddIntRelease(Object o, long offset, int delta) {
2685 int v;
2686 do {
2687 v = getInt(o, offset);
2688 } while (!weakCompareAndSetIntRelease(o, offset, v, v + delta));
2689 return v;
2690 }
2691
2692 @ForceInline
2693 public final int getAndAddIntAcquire(Object o, long offset, int delta) {
2694 int v;
2695 do {
2696 v = getIntAcquire(o, offset);
2697 } while (!weakCompareAndSetIntAcquire(o, offset, v, v + delta));
2698 return v;
2699 }
2700
2701 /**
2702 * Atomically adds the given value to the current value of a field
2703 * or array element within the given object {@code o}
2704 * at the given {@code offset}.
2705 *
2706 * @param o object/array to update the field/element in
2707 * @param offset field/element offset
2708 * @param delta the value to add
2709 * @return the previous value
2710 * @since 1.8
2711 */
2712 @HotSpotIntrinsicCandidate
2713 public final long getAndAddLong(Object o, long offset, long delta) {
2714 long v;
2715 do {
2716 v = getLongVolatile(o, offset);
2717 } while (!weakCompareAndSetLong(o, offset, v, v + delta));
2718 return v;
2719 }
2720
2721 @ForceInline
2722 public final long getAndAddLongRelease(Object o, long offset, long delta) {
2723 long v;
2724 do {
2725 v = getLong(o, offset);
2726 } while (!weakCompareAndSetLongRelease(o, offset, v, v + delta));
2727 return v;
2728 }
2729
2730 @ForceInline
2731 public final long getAndAddLongAcquire(Object o, long offset, long delta) {
2732 long v;
2733 do {
2734 v = getLongAcquire(o, offset);
2735 } while (!weakCompareAndSetLongAcquire(o, offset, v, v + delta));
2736 return v;
2737 }
2738
2739 @HotSpotIntrinsicCandidate
2740 public final byte getAndAddByte(Object o, long offset, byte delta) {
2741 byte v;
2742 do {
2743 v = getByteVolatile(o, offset);
2744 } while (!weakCompareAndSetByte(o, offset, v, (byte) (v + delta)));
2745 return v;
2746 }
2747
2748 @ForceInline
2749 public final byte getAndAddByteRelease(Object o, long offset, byte delta) {
2750 byte v;
2751 do {
2752 v = getByte(o, offset);
2753 } while (!weakCompareAndSetByteRelease(o, offset, v, (byte) (v + delta)));
2754 return v;
2755 }
2756
2757 @ForceInline
2758 public final byte getAndAddByteAcquire(Object o, long offset, byte delta) {
2759 byte v;
2760 do {
2761 v = getByteAcquire(o, offset);
2762 } while (!weakCompareAndSetByteAcquire(o, offset, v, (byte) (v + delta)));
2763 return v;
2764 }
2765
2766 @HotSpotIntrinsicCandidate
2767 public final short getAndAddShort(Object o, long offset, short delta) {
2768 short v;
2769 do {
2770 v = getShortVolatile(o, offset);
2771 } while (!weakCompareAndSetShort(o, offset, v, (short) (v + delta)));
2772 return v;
2773 }
2774
2775 @ForceInline
2776 public final short getAndAddShortRelease(Object o, long offset, short delta) {
2777 short v;
2778 do {
2779 v = getShort(o, offset);
2780 } while (!weakCompareAndSetShortRelease(o, offset, v, (short) (v + delta)));
2781 return v;
2782 }
2783
2784 @ForceInline
2785 public final short getAndAddShortAcquire(Object o, long offset, short delta) {
2786 short v;
2787 do {
2788 v = getShortAcquire(o, offset);
2789 } while (!weakCompareAndSetShortAcquire(o, offset, v, (short) (v + delta)));
2790 return v;
2791 }
2792
2793 @ForceInline
2794 public final char getAndAddChar(Object o, long offset, char delta) {
2795 return (char) getAndAddShort(o, offset, (short) delta);
2796 }
2797
2798 @ForceInline
2799 public final char getAndAddCharRelease(Object o, long offset, char delta) {
2800 return (char) getAndAddShortRelease(o, offset, (short) delta);
2801 }
2802
2803 @ForceInline
2804 public final char getAndAddCharAcquire(Object o, long offset, char delta) {
2805 return (char) getAndAddShortAcquire(o, offset, (short) delta);
2806 }
2807
2808 @ForceInline
2809 public final float getAndAddFloat(Object o, long offset, float delta) {
2810 int expectedBits;
2811 float v;
2812 do {
2813 // Load and CAS with the raw bits to avoid issues with NaNs and
2814 // possible bit conversion from signaling NaNs to quiet NaNs that
2815 // may result in the loop not terminating.
2816 expectedBits = getIntVolatile(o, offset);
2817 v = Float.intBitsToFloat(expectedBits);
2818 } while (!weakCompareAndSetInt(o, offset,
2819 expectedBits, Float.floatToRawIntBits(v + delta)));
2820 return v;
2821 }
2822
2823 @ForceInline
2824 public final float getAndAddFloatRelease(Object o, long offset, float delta) {
2825 int expectedBits;
2826 float v;
2827 do {
2828 // Load and CAS with the raw bits to avoid issues with NaNs and
2829 // possible bit conversion from signaling NaNs to quiet NaNs that
2830 // may result in the loop not terminating.
2831 expectedBits = getInt(o, offset);
2832 v = Float.intBitsToFloat(expectedBits);
2833 } while (!weakCompareAndSetIntRelease(o, offset,
2834 expectedBits, Float.floatToRawIntBits(v + delta)));
2835 return v;
2836 }
2837
2838 @ForceInline
2839 public final float getAndAddFloatAcquire(Object o, long offset, float delta) {
2840 int expectedBits;
2841 float v;
2842 do {
2843 // Load and CAS with the raw bits to avoid issues with NaNs and
2844 // possible bit conversion from signaling NaNs to quiet NaNs that
2845 // may result in the loop not terminating.
2846 expectedBits = getIntAcquire(o, offset);
2847 v = Float.intBitsToFloat(expectedBits);
2848 } while (!weakCompareAndSetIntAcquire(o, offset,
2849 expectedBits, Float.floatToRawIntBits(v + delta)));
2850 return v;
2851 }
2852
2853 @ForceInline
2854 public final double getAndAddDouble(Object o, long offset, double delta) {
2855 long expectedBits;
2856 double v;
2857 do {
2858 // Load and CAS with the raw bits to avoid issues with NaNs and
2859 // possible bit conversion from signaling NaNs to quiet NaNs that
2860 // may result in the loop not terminating.
2861 expectedBits = getLongVolatile(o, offset);
2862 v = Double.longBitsToDouble(expectedBits);
2863 } while (!weakCompareAndSetLong(o, offset,
2864 expectedBits, Double.doubleToRawLongBits(v + delta)));
2865 return v;
2866 }
2867
2868 @ForceInline
2869 public final double getAndAddDoubleRelease(Object o, long offset, double delta) {
2870 long expectedBits;
2871 double v;
2872 do {
2873 // Load and CAS with the raw bits to avoid issues with NaNs and
2874 // possible bit conversion from signaling NaNs to quiet NaNs that
2875 // may result in the loop not terminating.
2876 expectedBits = getLong(o, offset);
2877 v = Double.longBitsToDouble(expectedBits);
2878 } while (!weakCompareAndSetLongRelease(o, offset,
2879 expectedBits, Double.doubleToRawLongBits(v + delta)));
2880 return v;
2881 }
2882
2883 @ForceInline
2884 public final double getAndAddDoubleAcquire(Object o, long offset, double delta) {
2885 long expectedBits;
2886 double v;
2887 do {
2888 // Load and CAS with the raw bits to avoid issues with NaNs and
2889 // possible bit conversion from signaling NaNs to quiet NaNs that
2890 // may result in the loop not terminating.
2891 expectedBits = getLongAcquire(o, offset);
2892 v = Double.longBitsToDouble(expectedBits);
2893 } while (!weakCompareAndSetLongAcquire(o, offset,
2894 expectedBits, Double.doubleToRawLongBits(v + delta)));
2895 return v;
2896 }
2897
2898 /**
2899 * Atomically exchanges the given value with the current value of
2900 * a field or array element within the given object {@code o}
2901 * at the given {@code offset}.
2902 *
2903 * @param o object/array to update the field/element in
2904 * @param offset field/element offset
2905 * @param newValue new value
2906 * @return the previous value
2907 * @since 1.8
2908 */
2909 @HotSpotIntrinsicCandidate
2910 public final int getAndSetInt(Object o, long offset, int newValue) {
2911 int v;
2912 do {
2913 v = getIntVolatile(o, offset);
2914 } while (!weakCompareAndSetInt(o, offset, v, newValue));
2915 return v;
2916 }
2917
2918 @ForceInline
2919 public final int getAndSetIntRelease(Object o, long offset, int newValue) {
2920 int v;
2921 do {
2922 v = getInt(o, offset);
2923 } while (!weakCompareAndSetIntRelease(o, offset, v, newValue));
2924 return v;
2925 }
2926
2927 @ForceInline
2928 public final int getAndSetIntAcquire(Object o, long offset, int newValue) {
2929 int v;
2930 do {
2931 v = getIntAcquire(o, offset);
2932 } while (!weakCompareAndSetIntAcquire(o, offset, v, newValue));
2933 return v;
2934 }
2935
2936 /**
2937 * Atomically exchanges the given value with the current value of
2938 * a field or array element within the given object {@code o}
2939 * at the given {@code offset}.
2940 *
2941 * @param o object/array to update the field/element in
2942 * @param offset field/element offset
2943 * @param newValue new value
2944 * @return the previous value
2945 * @since 1.8
2946 */
2947 @HotSpotIntrinsicCandidate
2948 public final long getAndSetLong(Object o, long offset, long newValue) {
2949 long v;
2950 do {
2951 v = getLongVolatile(o, offset);
2952 } while (!weakCompareAndSetLong(o, offset, v, newValue));
2953 return v;
2954 }
2955
2956 @ForceInline
2957 public final long getAndSetLongRelease(Object o, long offset, long newValue) {
2958 long v;
2959 do {
2960 v = getLong(o, offset);
2961 } while (!weakCompareAndSetLongRelease(o, offset, v, newValue));
2962 return v;
2963 }
2964
2965 @ForceInline
2966 public final long getAndSetLongAcquire(Object o, long offset, long newValue) {
2967 long v;
2968 do {
2969 v = getLongAcquire(o, offset);
2970 } while (!weakCompareAndSetLongAcquire(o, offset, v, newValue));
2971 return v;
2972 }
2973
2974 /**
2975 * Atomically exchanges the given reference value with the current
2976 * reference value of a field or array element within the given
2977 * object {@code o} at the given {@code offset}.
2978 *
2979 * @param o object/array to update the field/element in
2980 * @param offset field/element offset
2981 * @param newValue new value
2982 * @return the previous value
2983 * @since 1.8
2984 */
2985 @HotSpotIntrinsicCandidate
2986 public final Object getAndSetReference(Object o, long offset, Object newValue) {
2987 Object v;
2988 do {
2989 v = getReferenceVolatile(o, offset);
2990 } while (!weakCompareAndSetReference(o, offset, v, newValue));
2991 return v;
2992 }
2993
2994 @SuppressWarnings("unchecked")
2995 public final <V> Object getAndSetValue(Object o, long offset, Class<?> valueType, V newValue) {
2996 synchronized (valueLock) {
2997 Object oldValue = getValue(o, offset, valueType);
2998 putValue(o, offset, valueType, newValue);
2999 return oldValue;
3000 }
3001 }
3002
3003 @ForceInline
3004 public final Object getAndSetReferenceRelease(Object o, long offset, Object newValue) {
3005 Object v;
3006 do {
3007 v = getReference(o, offset);
3008 } while (!weakCompareAndSetReferenceRelease(o, offset, v, newValue));
3009 return v;
3010 }
3011
3012 @ForceInline
3013 public final <V> Object getAndSetValueRelease(Object o, long offset, Class<?> valueType, V newValue) {
3014 return getAndSetValue(o, offset, valueType, newValue);
3015 }
3016
3017 @ForceInline
3018 public final Object getAndSetReferenceAcquire(Object o, long offset, Object newValue) {
3019 Object v;
3020 do {
3021 v = getReferenceAcquire(o, offset);
3022 } while (!weakCompareAndSetReferenceAcquire(o, offset, v, newValue));
3023 return v;
3024 }
3025
3026 @ForceInline
3027 public final <V> Object getAndSetValueAcquire(Object o, long offset, Class<?> valueType, V newValue) {
3028 return getAndSetValue(o, offset, valueType, newValue);
3029 }
3030
3031 @HotSpotIntrinsicCandidate
3032 public final byte getAndSetByte(Object o, long offset, byte newValue) {
3033 byte v;
3034 do {
3035 v = getByteVolatile(o, offset);
3036 } while (!weakCompareAndSetByte(o, offset, v, newValue));
3037 return v;
3038 }
3039
3040 @ForceInline
3041 public final byte getAndSetByteRelease(Object o, long offset, byte newValue) {
3042 byte v;
3043 do {
3044 v = getByte(o, offset);
3045 } while (!weakCompareAndSetByteRelease(o, offset, v, newValue));
3046 return v;
3047 }
3048
3049 @ForceInline
3050 public final byte getAndSetByteAcquire(Object o, long offset, byte newValue) {
3051 byte v;
3052 do {
3053 v = getByteAcquire(o, offset);
3054 } while (!weakCompareAndSetByteAcquire(o, offset, v, newValue));
3055 return v;
3056 }
3057
3058 @ForceInline
3059 public final boolean getAndSetBoolean(Object o, long offset, boolean newValue) {
3060 return byte2bool(getAndSetByte(o, offset, bool2byte(newValue)));
3061 }
3062
3063 @ForceInline
3064 public final boolean getAndSetBooleanRelease(Object o, long offset, boolean newValue) {
3065 return byte2bool(getAndSetByteRelease(o, offset, bool2byte(newValue)));
3066 }
3067
3068 @ForceInline
3069 public final boolean getAndSetBooleanAcquire(Object o, long offset, boolean newValue) {
3070 return byte2bool(getAndSetByteAcquire(o, offset, bool2byte(newValue)));
3071 }
3072
3073 @HotSpotIntrinsicCandidate
3074 public final short getAndSetShort(Object o, long offset, short newValue) {
3075 short v;
3076 do {
3077 v = getShortVolatile(o, offset);
3078 } while (!weakCompareAndSetShort(o, offset, v, newValue));
3079 return v;
3080 }
3081
3082 @ForceInline
3083 public final short getAndSetShortRelease(Object o, long offset, short newValue) {
3084 short v;
3085 do {
3086 v = getShort(o, offset);
3087 } while (!weakCompareAndSetShortRelease(o, offset, v, newValue));
3088 return v;
3089 }
3090
3091 @ForceInline
3092 public final short getAndSetShortAcquire(Object o, long offset, short newValue) {
3093 short v;
3094 do {
3095 v = getShortAcquire(o, offset);
3096 } while (!weakCompareAndSetShortAcquire(o, offset, v, newValue));
3097 return v;
3098 }
3099
3100 @ForceInline
3101 public final char getAndSetChar(Object o, long offset, char newValue) {
3102 return s2c(getAndSetShort(o, offset, c2s(newValue)));
3103 }
3104
3105 @ForceInline
3106 public final char getAndSetCharRelease(Object o, long offset, char newValue) {
3107 return s2c(getAndSetShortRelease(o, offset, c2s(newValue)));
3108 }
3109
3110 @ForceInline
3111 public final char getAndSetCharAcquire(Object o, long offset, char newValue) {
3112 return s2c(getAndSetShortAcquire(o, offset, c2s(newValue)));
3113 }
3114
3115 @ForceInline
3116 public final float getAndSetFloat(Object o, long offset, float newValue) {
3117 int v = getAndSetInt(o, offset, Float.floatToRawIntBits(newValue));
3118 return Float.intBitsToFloat(v);
3119 }
3120
3121 @ForceInline
3122 public final float getAndSetFloatRelease(Object o, long offset, float newValue) {
3123 int v = getAndSetIntRelease(o, offset, Float.floatToRawIntBits(newValue));
3124 return Float.intBitsToFloat(v);
3125 }
3126
3127 @ForceInline
3128 public final float getAndSetFloatAcquire(Object o, long offset, float newValue) {
3129 int v = getAndSetIntAcquire(o, offset, Float.floatToRawIntBits(newValue));
3130 return Float.intBitsToFloat(v);
3131 }
3132
3133 @ForceInline
3134 public final double getAndSetDouble(Object o, long offset, double newValue) {
3135 long v = getAndSetLong(o, offset, Double.doubleToRawLongBits(newValue));
3136 return Double.longBitsToDouble(v);
3137 }
3138
3139 @ForceInline
3140 public final double getAndSetDoubleRelease(Object o, long offset, double newValue) {
3141 long v = getAndSetLongRelease(o, offset, Double.doubleToRawLongBits(newValue));
3142 return Double.longBitsToDouble(v);
3143 }
3144
3145 @ForceInline
3146 public final double getAndSetDoubleAcquire(Object o, long offset, double newValue) {
3147 long v = getAndSetLongAcquire(o, offset, Double.doubleToRawLongBits(newValue));
3148 return Double.longBitsToDouble(v);
3149 }
3150
3151
3152 // The following contain CAS-based Java implementations used on
3153 // platforms not supporting native instructions
3154
3155 @ForceInline
3156 public final boolean getAndBitwiseOrBoolean(Object o, long offset, boolean mask) {
3157 return byte2bool(getAndBitwiseOrByte(o, offset, bool2byte(mask)));
3158 }
3159
3160 @ForceInline
3161 public final boolean getAndBitwiseOrBooleanRelease(Object o, long offset, boolean mask) {
3162 return byte2bool(getAndBitwiseOrByteRelease(o, offset, bool2byte(mask)));
3163 }
3164
3165 @ForceInline
3166 public final boolean getAndBitwiseOrBooleanAcquire(Object o, long offset, boolean mask) {
3167 return byte2bool(getAndBitwiseOrByteAcquire(o, offset, bool2byte(mask)));
3168 }
3169
3170 @ForceInline
3171 public final boolean getAndBitwiseAndBoolean(Object o, long offset, boolean mask) {
3172 return byte2bool(getAndBitwiseAndByte(o, offset, bool2byte(mask)));
3173 }
3174
3175 @ForceInline
3176 public final boolean getAndBitwiseAndBooleanRelease(Object o, long offset, boolean mask) {
3177 return byte2bool(getAndBitwiseAndByteRelease(o, offset, bool2byte(mask)));
3178 }
3179
3180 @ForceInline
3181 public final boolean getAndBitwiseAndBooleanAcquire(Object o, long offset, boolean mask) {
3182 return byte2bool(getAndBitwiseAndByteAcquire(o, offset, bool2byte(mask)));
3183 }
3184
3185 @ForceInline
3186 public final boolean getAndBitwiseXorBoolean(Object o, long offset, boolean mask) {
3187 return byte2bool(getAndBitwiseXorByte(o, offset, bool2byte(mask)));
3188 }
3189
3190 @ForceInline
3191 public final boolean getAndBitwiseXorBooleanRelease(Object o, long offset, boolean mask) {
3192 return byte2bool(getAndBitwiseXorByteRelease(o, offset, bool2byte(mask)));
3193 }
3194
3195 @ForceInline
3196 public final boolean getAndBitwiseXorBooleanAcquire(Object o, long offset, boolean mask) {
3197 return byte2bool(getAndBitwiseXorByteAcquire(o, offset, bool2byte(mask)));
3198 }
3199
3200
3201 @ForceInline
3202 public final byte getAndBitwiseOrByte(Object o, long offset, byte mask) {
3203 byte current;
3204 do {
3205 current = getByteVolatile(o, offset);
3206 } while (!weakCompareAndSetByte(o, offset,
3207 current, (byte) (current | mask)));
3208 return current;
3209 }
3210
3211 @ForceInline
3212 public final byte getAndBitwiseOrByteRelease(Object o, long offset, byte mask) {
3213 byte current;
3214 do {
3215 current = getByte(o, offset);
3216 } while (!weakCompareAndSetByteRelease(o, offset,
3217 current, (byte) (current | mask)));
3218 return current;
3219 }
3220
3221 @ForceInline
3222 public final byte getAndBitwiseOrByteAcquire(Object o, long offset, byte mask) {
3223 byte current;
3224 do {
3225 // Plain read, the value is a hint, the acquire CAS does the work
3226 current = getByte(o, offset);
3227 } while (!weakCompareAndSetByteAcquire(o, offset,
3228 current, (byte) (current | mask)));
3229 return current;
3230 }
3231
3232 @ForceInline
3233 public final byte getAndBitwiseAndByte(Object o, long offset, byte mask) {
3234 byte current;
3235 do {
3236 current = getByteVolatile(o, offset);
3237 } while (!weakCompareAndSetByte(o, offset,
3238 current, (byte) (current & mask)));
3239 return current;
3240 }
3241
3242 @ForceInline
3243 public final byte getAndBitwiseAndByteRelease(Object o, long offset, byte mask) {
3244 byte current;
3245 do {
3246 current = getByte(o, offset);
3247 } while (!weakCompareAndSetByteRelease(o, offset,
3248 current, (byte) (current & mask)));
3249 return current;
3250 }
3251
3252 @ForceInline
3253 public final byte getAndBitwiseAndByteAcquire(Object o, long offset, byte mask) {
3254 byte current;
3255 do {
3256 // Plain read, the value is a hint, the acquire CAS does the work
3257 current = getByte(o, offset);
3258 } while (!weakCompareAndSetByteAcquire(o, offset,
3259 current, (byte) (current & mask)));
3260 return current;
3261 }
3262
3263 @ForceInline
3264 public final byte getAndBitwiseXorByte(Object o, long offset, byte mask) {
3265 byte current;
3266 do {
3267 current = getByteVolatile(o, offset);
3268 } while (!weakCompareAndSetByte(o, offset,
3269 current, (byte) (current ^ mask)));
3270 return current;
3271 }
3272
3273 @ForceInline
3274 public final byte getAndBitwiseXorByteRelease(Object o, long offset, byte mask) {
3275 byte current;
3276 do {
3277 current = getByte(o, offset);
3278 } while (!weakCompareAndSetByteRelease(o, offset,
3279 current, (byte) (current ^ mask)));
3280 return current;
3281 }
3282
3283 @ForceInline
3284 public final byte getAndBitwiseXorByteAcquire(Object o, long offset, byte mask) {
3285 byte current;
3286 do {
3287 // Plain read, the value is a hint, the acquire CAS does the work
3288 current = getByte(o, offset);
3289 } while (!weakCompareAndSetByteAcquire(o, offset,
3290 current, (byte) (current ^ mask)));
3291 return current;
3292 }
3293
3294
3295 @ForceInline
3296 public final char getAndBitwiseOrChar(Object o, long offset, char mask) {
3297 return s2c(getAndBitwiseOrShort(o, offset, c2s(mask)));
3298 }
3299
3300 @ForceInline
3301 public final char getAndBitwiseOrCharRelease(Object o, long offset, char mask) {
3302 return s2c(getAndBitwiseOrShortRelease(o, offset, c2s(mask)));
3303 }
3304
3305 @ForceInline
3306 public final char getAndBitwiseOrCharAcquire(Object o, long offset, char mask) {
3307 return s2c(getAndBitwiseOrShortAcquire(o, offset, c2s(mask)));
3308 }
3309
3310 @ForceInline
3311 public final char getAndBitwiseAndChar(Object o, long offset, char mask) {
3312 return s2c(getAndBitwiseAndShort(o, offset, c2s(mask)));
3313 }
3314
3315 @ForceInline
3316 public final char getAndBitwiseAndCharRelease(Object o, long offset, char mask) {
3317 return s2c(getAndBitwiseAndShortRelease(o, offset, c2s(mask)));
3318 }
3319
3320 @ForceInline
3321 public final char getAndBitwiseAndCharAcquire(Object o, long offset, char mask) {
3322 return s2c(getAndBitwiseAndShortAcquire(o, offset, c2s(mask)));
3323 }
3324
3325 @ForceInline
3326 public final char getAndBitwiseXorChar(Object o, long offset, char mask) {
3327 return s2c(getAndBitwiseXorShort(o, offset, c2s(mask)));
3328 }
3329
3330 @ForceInline
3331 public final char getAndBitwiseXorCharRelease(Object o, long offset, char mask) {
3332 return s2c(getAndBitwiseXorShortRelease(o, offset, c2s(mask)));
3333 }
3334
3335 @ForceInline
3336 public final char getAndBitwiseXorCharAcquire(Object o, long offset, char mask) {
3337 return s2c(getAndBitwiseXorShortAcquire(o, offset, c2s(mask)));
3338 }
3339
3340
3341 @ForceInline
3342 public final short getAndBitwiseOrShort(Object o, long offset, short mask) {
3343 short current;
3344 do {
3345 current = getShortVolatile(o, offset);
3346 } while (!weakCompareAndSetShort(o, offset,
3347 current, (short) (current | mask)));
3348 return current;
3349 }
3350
3351 @ForceInline
3352 public final short getAndBitwiseOrShortRelease(Object o, long offset, short mask) {
3353 short current;
3354 do {
3355 current = getShort(o, offset);
3356 } while (!weakCompareAndSetShortRelease(o, offset,
3357 current, (short) (current | mask)));
3358 return current;
3359 }
3360
3361 @ForceInline
3362 public final short getAndBitwiseOrShortAcquire(Object o, long offset, short mask) {
3363 short current;
3364 do {
3365 // Plain read, the value is a hint, the acquire CAS does the work
3366 current = getShort(o, offset);
3367 } while (!weakCompareAndSetShortAcquire(o, offset,
3368 current, (short) (current | mask)));
3369 return current;
3370 }
3371
3372 @ForceInline
3373 public final short getAndBitwiseAndShort(Object o, long offset, short mask) {
3374 short current;
3375 do {
3376 current = getShortVolatile(o, offset);
3377 } while (!weakCompareAndSetShort(o, offset,
3378 current, (short) (current & mask)));
3379 return current;
3380 }
3381
3382 @ForceInline
3383 public final short getAndBitwiseAndShortRelease(Object o, long offset, short mask) {
3384 short current;
3385 do {
3386 current = getShort(o, offset);
3387 } while (!weakCompareAndSetShortRelease(o, offset,
3388 current, (short) (current & mask)));
3389 return current;
3390 }
3391
3392 @ForceInline
3393 public final short getAndBitwiseAndShortAcquire(Object o, long offset, short mask) {
3394 short current;
3395 do {
3396 // Plain read, the value is a hint, the acquire CAS does the work
3397 current = getShort(o, offset);
3398 } while (!weakCompareAndSetShortAcquire(o, offset,
3399 current, (short) (current & mask)));
3400 return current;
3401 }
3402
3403 @ForceInline
3404 public final short getAndBitwiseXorShort(Object o, long offset, short mask) {
3405 short current;
3406 do {
3407 current = getShortVolatile(o, offset);
3408 } while (!weakCompareAndSetShort(o, offset,
3409 current, (short) (current ^ mask)));
3410 return current;
3411 }
3412
3413 @ForceInline
3414 public final short getAndBitwiseXorShortRelease(Object o, long offset, short mask) {
3415 short current;
3416 do {
3417 current = getShort(o, offset);
3418 } while (!weakCompareAndSetShortRelease(o, offset,
3419 current, (short) (current ^ mask)));
3420 return current;
3421 }
3422
3423 @ForceInline
3424 public final short getAndBitwiseXorShortAcquire(Object o, long offset, short mask) {
3425 short current;
3426 do {
3427 // Plain read, the value is a hint, the acquire CAS does the work
3428 current = getShort(o, offset);
3429 } while (!weakCompareAndSetShortAcquire(o, offset,
3430 current, (short) (current ^ mask)));
3431 return current;
3432 }
3433
3434
3435 @ForceInline
3436 public final int getAndBitwiseOrInt(Object o, long offset, int mask) {
3437 int current;
3438 do {
3439 current = getIntVolatile(o, offset);
3440 } while (!weakCompareAndSetInt(o, offset,
3441 current, current | mask));
3442 return current;
3443 }
3444
3445 @ForceInline
3446 public final int getAndBitwiseOrIntRelease(Object o, long offset, int mask) {
3447 int current;
3448 do {
3449 current = getInt(o, offset);
3450 } while (!weakCompareAndSetIntRelease(o, offset,
3451 current, current | mask));
3452 return current;
3453 }
3454
3455 @ForceInline
3456 public final int getAndBitwiseOrIntAcquire(Object o, long offset, int mask) {
3457 int current;
3458 do {
3459 // Plain read, the value is a hint, the acquire CAS does the work
3460 current = getInt(o, offset);
3461 } while (!weakCompareAndSetIntAcquire(o, offset,
3462 current, current | mask));
3463 return current;
3464 }
3465
3466 /**
3467 * Atomically replaces the current value of a field or array element within
3468 * the given object with the result of bitwise AND between the current value
3469 * and mask.
3470 *
3471 * @param o object/array to update the field/element in
3472 * @param offset field/element offset
3473 * @param mask the mask value
3474 * @return the previous value
3475 * @since 9
3476 */
3477 @ForceInline
3478 public final int getAndBitwiseAndInt(Object o, long offset, int mask) {
3479 int current;
3480 do {
3481 current = getIntVolatile(o, offset);
3482 } while (!weakCompareAndSetInt(o, offset,
3483 current, current & mask));
3484 return current;
3485 }
3486
3487 @ForceInline
3488 public final int getAndBitwiseAndIntRelease(Object o, long offset, int mask) {
3489 int current;
3490 do {
3491 current = getInt(o, offset);
3492 } while (!weakCompareAndSetIntRelease(o, offset,
3493 current, current & mask));
3494 return current;
3495 }
3496
3497 @ForceInline
3498 public final int getAndBitwiseAndIntAcquire(Object o, long offset, int mask) {
3499 int current;
3500 do {
3501 // Plain read, the value is a hint, the acquire CAS does the work
3502 current = getInt(o, offset);
3503 } while (!weakCompareAndSetIntAcquire(o, offset,
3504 current, current & mask));
3505 return current;
3506 }
3507
3508 @ForceInline
3509 public final int getAndBitwiseXorInt(Object o, long offset, int mask) {
3510 int current;
3511 do {
3512 current = getIntVolatile(o, offset);
3513 } while (!weakCompareAndSetInt(o, offset,
3514 current, current ^ mask));
3515 return current;
3516 }
3517
3518 @ForceInline
3519 public final int getAndBitwiseXorIntRelease(Object o, long offset, int mask) {
3520 int current;
3521 do {
3522 current = getInt(o, offset);
3523 } while (!weakCompareAndSetIntRelease(o, offset,
3524 current, current ^ mask));
3525 return current;
3526 }
3527
3528 @ForceInline
3529 public final int getAndBitwiseXorIntAcquire(Object o, long offset, int mask) {
3530 int current;
3531 do {
3532 // Plain read, the value is a hint, the acquire CAS does the work
3533 current = getInt(o, offset);
3534 } while (!weakCompareAndSetIntAcquire(o, offset,
3535 current, current ^ mask));
3536 return current;
3537 }
3538
3539
3540 @ForceInline
3541 public final long getAndBitwiseOrLong(Object o, long offset, long mask) {
3542 long current;
3543 do {
3544 current = getLongVolatile(o, offset);
3545 } while (!weakCompareAndSetLong(o, offset,
3546 current, current | mask));
3547 return current;
3548 }
3549
3550 @ForceInline
3551 public final long getAndBitwiseOrLongRelease(Object o, long offset, long mask) {
3552 long current;
3553 do {
3554 current = getLong(o, offset);
3555 } while (!weakCompareAndSetLongRelease(o, offset,
3556 current, current | mask));
3557 return current;
3558 }
3559
3560 @ForceInline
3561 public final long getAndBitwiseOrLongAcquire(Object o, long offset, long mask) {
3562 long current;
3563 do {
3564 // Plain read, the value is a hint, the acquire CAS does the work
3565 current = getLong(o, offset);
3566 } while (!weakCompareAndSetLongAcquire(o, offset,
3567 current, current | mask));
3568 return current;
3569 }
3570
3571 @ForceInline
3572 public final long getAndBitwiseAndLong(Object o, long offset, long mask) {
3573 long current;
3574 do {
3575 current = getLongVolatile(o, offset);
3576 } while (!weakCompareAndSetLong(o, offset,
3577 current, current & mask));
3578 return current;
3579 }
3580
3581 @ForceInline
3582 public final long getAndBitwiseAndLongRelease(Object o, long offset, long mask) {
3583 long current;
3584 do {
3585 current = getLong(o, offset);
3586 } while (!weakCompareAndSetLongRelease(o, offset,
3587 current, current & mask));
3588 return current;
3589 }
3590
3591 @ForceInline
3592 public final long getAndBitwiseAndLongAcquire(Object o, long offset, long mask) {
3593 long current;
3594 do {
3595 // Plain read, the value is a hint, the acquire CAS does the work
3596 current = getLong(o, offset);
3597 } while (!weakCompareAndSetLongAcquire(o, offset,
3598 current, current & mask));
3599 return current;
3600 }
3601
3602 @ForceInline
3603 public final long getAndBitwiseXorLong(Object o, long offset, long mask) {
3604 long current;
3605 do {
3606 current = getLongVolatile(o, offset);
3607 } while (!weakCompareAndSetLong(o, offset,
3608 current, current ^ mask));
3609 return current;
3610 }
3611
3612 @ForceInline
3613 public final long getAndBitwiseXorLongRelease(Object o, long offset, long mask) {
3614 long current;
3615 do {
3616 current = getLong(o, offset);
3617 } while (!weakCompareAndSetLongRelease(o, offset,
3618 current, current ^ mask));
3619 return current;
3620 }
3621
3622 @ForceInline
3623 public final long getAndBitwiseXorLongAcquire(Object o, long offset, long mask) {
3624 long current;
3625 do {
3626 // Plain read, the value is a hint, the acquire CAS does the work
3627 current = getLong(o, offset);
3628 } while (!weakCompareAndSetLongAcquire(o, offset,
3629 current, current ^ mask));
3630 return current;
3631 }
3632
3633
3634
3635 /**
3636 * Ensures that loads before the fence will not be reordered with loads and
3637 * stores after the fence; a "LoadLoad plus LoadStore barrier".
3638 *
3639 * Corresponds to C11 atomic_thread_fence(memory_order_acquire)
3640 * (an "acquire fence").
3641 *
3642 * A pure LoadLoad fence is not provided, since the addition of LoadStore
3643 * is almost always desired, and most current hardware instructions that
3644 * provide a LoadLoad barrier also provide a LoadStore barrier for free.
3645 * @since 1.8
3646 */
3647 @HotSpotIntrinsicCandidate
3648 public native void loadFence();
3649
3650 /**
3651 * Ensures that loads and stores before the fence will not be reordered with
3652 * stores after the fence; a "StoreStore plus LoadStore barrier".
3653 *
3654 * Corresponds to C11 atomic_thread_fence(memory_order_release)
3655 * (a "release fence").
3656 *
3657 * A pure StoreStore fence is not provided, since the addition of LoadStore
3658 * is almost always desired, and most current hardware instructions that
3659 * provide a StoreStore barrier also provide a LoadStore barrier for free.
3660 * @since 1.8
3661 */
3662 @HotSpotIntrinsicCandidate
3663 public native void storeFence();
3664
3665 /**
3666 * Ensures that loads and stores before the fence will not be reordered
3667 * with loads and stores after the fence. Implies the effects of both
3668 * loadFence() and storeFence(), and in addition, the effect of a StoreLoad
3669 * barrier.
3670 *
3671 * Corresponds to C11 atomic_thread_fence(memory_order_seq_cst).
3672 * @since 1.8
3673 */
3674 @HotSpotIntrinsicCandidate
3675 public native void fullFence();
3676
3677 /**
3678 * Ensures that loads before the fence will not be reordered with
3679 * loads after the fence.
3680 */
3681 public final void loadLoadFence() {
3682 loadFence();
3683 }
3684
3685 /**
3686 * Ensures that stores before the fence will not be reordered with
3687 * stores after the fence.
3688 */
3689 public final void storeStoreFence() {
3690 storeFence();
3691 }
3692
3693
3694 /**
3695 * Throws IllegalAccessError; for use by the VM for access control
3696 * error support.
3697 * @since 1.8
3698 */
3699 private static void throwIllegalAccessError() {
3700 throw new IllegalAccessError();
3701 }
3702
3703 /**
3704 * Throws NoSuchMethodError; for use by the VM for redefinition support.
3705 * @since 13
3706 */
3707 private static void throwNoSuchMethodError() {
3708 throw new NoSuchMethodError();
3709 }
3710
3711 /**
3712 * @return Returns true if the native byte ordering of this
3713 * platform is big-endian, false if it is little-endian.
3714 */
3715 public final boolean isBigEndian() { return BIG_ENDIAN; }
3716
3717 /**
3718 * @return Returns true if this platform is capable of performing
3719 * accesses at addresses which are not aligned for the type of the
3720 * primitive type being accessed, false otherwise.
3721 */
3722 public final boolean unalignedAccess() { return UNALIGNED_ACCESS; }
3723
3724 /**
3725 * Fetches a value at some byte offset into a given Java object.
3726 * More specifically, fetches a value within the given object
3727 * <code>o</code> at the given offset, or (if <code>o</code> is
3728 * null) from the memory address whose numerical value is the
3729 * given offset. <p>
3730 *
3731 * The specification of this method is the same as {@link
3732 * #getLong(Object, long)} except that the offset does not need to
3733 * have been obtained from {@link #objectFieldOffset} on the
3734 * {@link java.lang.reflect.Field} of some Java field. The value
3735 * in memory is raw data, and need not correspond to any Java
3736 * variable. Unless <code>o</code> is null, the value accessed
3737 * must be entirely within the allocated object. The endianness
3738 * of the value in memory is the endianness of the native platform.
3739 *
3740 * <p> The read will be atomic with respect to the largest power
3741 * of two that divides the GCD of the offset and the storage size.
3742 * For example, getLongUnaligned will make atomic reads of 2-, 4-,
3743 * or 8-byte storage units if the offset is zero mod 2, 4, or 8,
3744 * respectively. There are no other guarantees of atomicity.
3745 * <p>
3746 * 8-byte atomicity is only guaranteed on platforms on which
3747 * support atomic accesses to longs.
3748 *
3749 * @param o Java heap object in which the value resides, if any, else
3750 * null
3751 * @param offset The offset in bytes from the start of the object
3752 * @return the value fetched from the indicated object
3753 * @throws RuntimeException No defined exceptions are thrown, not even
3754 * {@link NullPointerException}
3755 * @since 9
3756 */
3757 @HotSpotIntrinsicCandidate
3758 public final long getLongUnaligned(Object o, long offset) {
3759 if ((offset & 7) == 0) {
3760 return getLong(o, offset);
3761 } else if ((offset & 3) == 0) {
3762 return makeLong(getInt(o, offset),
3763 getInt(o, offset + 4));
3764 } else if ((offset & 1) == 0) {
3765 return makeLong(getShort(o, offset),
3766 getShort(o, offset + 2),
3767 getShort(o, offset + 4),
3768 getShort(o, offset + 6));
3769 } else {
3770 return makeLong(getByte(o, offset),
3771 getByte(o, offset + 1),
3772 getByte(o, offset + 2),
3773 getByte(o, offset + 3),
3774 getByte(o, offset + 4),
3775 getByte(o, offset + 5),
3776 getByte(o, offset + 6),
3777 getByte(o, offset + 7));
3778 }
3779 }
3780 /**
3781 * As {@link #getLongUnaligned(Object, long)} but with an
3782 * additional argument which specifies the endianness of the value
3783 * as stored in memory.
3784 *
3785 * @param o Java heap object in which the variable resides
3786 * @param offset The offset in bytes from the start of the object
3787 * @param bigEndian The endianness of the value
3788 * @return the value fetched from the indicated object
3789 * @since 9
3790 */
3791 public final long getLongUnaligned(Object o, long offset, boolean bigEndian) {
3792 return convEndian(bigEndian, getLongUnaligned(o, offset));
3793 }
3794
3795 /** @see #getLongUnaligned(Object, long) */
3796 @HotSpotIntrinsicCandidate
3797 public final int getIntUnaligned(Object o, long offset) {
3798 if ((offset & 3) == 0) {
3799 return getInt(o, offset);
3800 } else if ((offset & 1) == 0) {
3801 return makeInt(getShort(o, offset),
3802 getShort(o, offset + 2));
3803 } else {
3804 return makeInt(getByte(o, offset),
3805 getByte(o, offset + 1),
3806 getByte(o, offset + 2),
3807 getByte(o, offset + 3));
3808 }
3809 }
3810 /** @see #getLongUnaligned(Object, long, boolean) */
3811 public final int getIntUnaligned(Object o, long offset, boolean bigEndian) {
3812 return convEndian(bigEndian, getIntUnaligned(o, offset));
3813 }
3814
3815 /** @see #getLongUnaligned(Object, long) */
3816 @HotSpotIntrinsicCandidate
3817 public final short getShortUnaligned(Object o, long offset) {
3818 if ((offset & 1) == 0) {
3819 return getShort(o, offset);
3820 } else {
3821 return makeShort(getByte(o, offset),
3822 getByte(o, offset + 1));
3823 }
3824 }
3825 /** @see #getLongUnaligned(Object, long, boolean) */
3826 public final short getShortUnaligned(Object o, long offset, boolean bigEndian) {
3827 return convEndian(bigEndian, getShortUnaligned(o, offset));
3828 }
3829
3830 /** @see #getLongUnaligned(Object, long) */
3831 @HotSpotIntrinsicCandidate
3832 public final char getCharUnaligned(Object o, long offset) {
3833 if ((offset & 1) == 0) {
3834 return getChar(o, offset);
3835 } else {
3836 return (char)makeShort(getByte(o, offset),
3837 getByte(o, offset + 1));
3838 }
3839 }
3840
3841 /** @see #getLongUnaligned(Object, long, boolean) */
3842 public final char getCharUnaligned(Object o, long offset, boolean bigEndian) {
3843 return convEndian(bigEndian, getCharUnaligned(o, offset));
3844 }
3845
3846 /**
3847 * Stores a value at some byte offset into a given Java object.
3848 * <p>
3849 * The specification of this method is the same as {@link
3850 * #getLong(Object, long)} except that the offset does not need to
3851 * have been obtained from {@link #objectFieldOffset} on the
3852 * {@link java.lang.reflect.Field} of some Java field. The value
3853 * in memory is raw data, and need not correspond to any Java
3854 * variable. The endianness of the value in memory is the
3855 * endianness of the native platform.
3856 * <p>
3857 * The write will be atomic with respect to the largest power of
3858 * two that divides the GCD of the offset and the storage size.
3859 * For example, putLongUnaligned will make atomic writes of 2-, 4-,
3860 * or 8-byte storage units if the offset is zero mod 2, 4, or 8,
3861 * respectively. There are no other guarantees of atomicity.
3862 * <p>
3863 * 8-byte atomicity is only guaranteed on platforms on which
3864 * support atomic accesses to longs.
3865 *
3866 * @param o Java heap object in which the value resides, if any, else
3867 * null
3868 * @param offset The offset in bytes from the start of the object
3869 * @param x the value to store
3870 * @throws RuntimeException No defined exceptions are thrown, not even
3871 * {@link NullPointerException}
3872 * @since 9
3873 */
3874 @HotSpotIntrinsicCandidate
3875 public final void putLongUnaligned(Object o, long offset, long x) {
3876 if ((offset & 7) == 0) {
3877 putLong(o, offset, x);
3878 } else if ((offset & 3) == 0) {
3879 putLongParts(o, offset,
3880 (int)(x >> 0),
3881 (int)(x >>> 32));
3882 } else if ((offset & 1) == 0) {
3883 putLongParts(o, offset,
3884 (short)(x >>> 0),
3885 (short)(x >>> 16),
3886 (short)(x >>> 32),
3887 (short)(x >>> 48));
3888 } else {
3889 putLongParts(o, offset,
3890 (byte)(x >>> 0),
3891 (byte)(x >>> 8),
3892 (byte)(x >>> 16),
3893 (byte)(x >>> 24),
3894 (byte)(x >>> 32),
3895 (byte)(x >>> 40),
3896 (byte)(x >>> 48),
3897 (byte)(x >>> 56));
3898 }
3899 }
3900
3901 /**
3902 * As {@link #putLongUnaligned(Object, long, long)} but with an additional
3903 * argument which specifies the endianness of the value as stored in memory.
3904 * @param o Java heap object in which the value resides
3905 * @param offset The offset in bytes from the start of the object
3906 * @param x the value to store
3907 * @param bigEndian The endianness of the value
3908 * @throws RuntimeException No defined exceptions are thrown, not even
3909 * {@link NullPointerException}
3910 * @since 9
3911 */
3912 public final void putLongUnaligned(Object o, long offset, long x, boolean bigEndian) {
3913 putLongUnaligned(o, offset, convEndian(bigEndian, x));
3914 }
3915
3916 /** @see #putLongUnaligned(Object, long, long) */
3917 @HotSpotIntrinsicCandidate
3918 public final void putIntUnaligned(Object o, long offset, int x) {
3919 if ((offset & 3) == 0) {
3920 putInt(o, offset, x);
3921 } else if ((offset & 1) == 0) {
3922 putIntParts(o, offset,
3923 (short)(x >> 0),
3924 (short)(x >>> 16));
3925 } else {
3926 putIntParts(o, offset,
3927 (byte)(x >>> 0),
3928 (byte)(x >>> 8),
3929 (byte)(x >>> 16),
3930 (byte)(x >>> 24));
3931 }
3932 }
3933 /** @see #putLongUnaligned(Object, long, long, boolean) */
3934 public final void putIntUnaligned(Object o, long offset, int x, boolean bigEndian) {
3935 putIntUnaligned(o, offset, convEndian(bigEndian, x));
3936 }
3937
3938 /** @see #putLongUnaligned(Object, long, long) */
3939 @HotSpotIntrinsicCandidate
3940 public final void putShortUnaligned(Object o, long offset, short x) {
3941 if ((offset & 1) == 0) {
3942 putShort(o, offset, x);
3943 } else {
3944 putShortParts(o, offset,
3945 (byte)(x >>> 0),
3946 (byte)(x >>> 8));
3947 }
3948 }
3949 /** @see #putLongUnaligned(Object, long, long, boolean) */
3950 public final void putShortUnaligned(Object o, long offset, short x, boolean bigEndian) {
3951 putShortUnaligned(o, offset, convEndian(bigEndian, x));
3952 }
3953
3954 /** @see #putLongUnaligned(Object, long, long) */
3955 @HotSpotIntrinsicCandidate
3956 public final void putCharUnaligned(Object o, long offset, char x) {
3957 putShortUnaligned(o, offset, (short)x);
3958 }
3959 /** @see #putLongUnaligned(Object, long, long, boolean) */
3960 public final void putCharUnaligned(Object o, long offset, char x, boolean bigEndian) {
3961 putCharUnaligned(o, offset, convEndian(bigEndian, x));
3962 }
3963
3964 private static int pickPos(int top, int pos) { return BIG_ENDIAN ? top - pos : pos; }
3965
3966 // These methods construct integers from bytes. The byte ordering
3967 // is the native endianness of this platform.
3968 private static long makeLong(byte i0, byte i1, byte i2, byte i3, byte i4, byte i5, byte i6, byte i7) {
3969 return ((toUnsignedLong(i0) << pickPos(56, 0))
3970 | (toUnsignedLong(i1) << pickPos(56, 8))
3971 | (toUnsignedLong(i2) << pickPos(56, 16))
3972 | (toUnsignedLong(i3) << pickPos(56, 24))
3973 | (toUnsignedLong(i4) << pickPos(56, 32))
3974 | (toUnsignedLong(i5) << pickPos(56, 40))
3975 | (toUnsignedLong(i6) << pickPos(56, 48))
3976 | (toUnsignedLong(i7) << pickPos(56, 56)));
3977 }
3978 private static long makeLong(short i0, short i1, short i2, short i3) {
3979 return ((toUnsignedLong(i0) << pickPos(48, 0))
3980 | (toUnsignedLong(i1) << pickPos(48, 16))
3981 | (toUnsignedLong(i2) << pickPos(48, 32))
3982 | (toUnsignedLong(i3) << pickPos(48, 48)));
3983 }
3984 private static long makeLong(int i0, int i1) {
3985 return (toUnsignedLong(i0) << pickPos(32, 0))
3986 | (toUnsignedLong(i1) << pickPos(32, 32));
3987 }
3988 private static int makeInt(short i0, short i1) {
3989 return (toUnsignedInt(i0) << pickPos(16, 0))
3990 | (toUnsignedInt(i1) << pickPos(16, 16));
3991 }
3992 private static int makeInt(byte i0, byte i1, byte i2, byte i3) {
3993 return ((toUnsignedInt(i0) << pickPos(24, 0))
3994 | (toUnsignedInt(i1) << pickPos(24, 8))
3995 | (toUnsignedInt(i2) << pickPos(24, 16))
3996 | (toUnsignedInt(i3) << pickPos(24, 24)));
3997 }
3998 private static short makeShort(byte i0, byte i1) {
3999 return (short)((toUnsignedInt(i0) << pickPos(8, 0))
4000 | (toUnsignedInt(i1) << pickPos(8, 8)));
4001 }
4002
4003 private static byte pick(byte le, byte be) { return BIG_ENDIAN ? be : le; }
4004 private static short pick(short le, short be) { return BIG_ENDIAN ? be : le; }
4005 private static int pick(int le, int be) { return BIG_ENDIAN ? be : le; }
4006
4007 // These methods write integers to memory from smaller parts
4008 // provided by their caller. The ordering in which these parts
4009 // are written is the native endianness of this platform.
4010 private void putLongParts(Object o, long offset, byte i0, byte i1, byte i2, byte i3, byte i4, byte i5, byte i6, byte i7) {
4011 putByte(o, offset + 0, pick(i0, i7));
4012 putByte(o, offset + 1, pick(i1, i6));
4013 putByte(o, offset + 2, pick(i2, i5));
4014 putByte(o, offset + 3, pick(i3, i4));
4015 putByte(o, offset + 4, pick(i4, i3));
4016 putByte(o, offset + 5, pick(i5, i2));
4017 putByte(o, offset + 6, pick(i6, i1));
4018 putByte(o, offset + 7, pick(i7, i0));
4019 }
4020 private void putLongParts(Object o, long offset, short i0, short i1, short i2, short i3) {
4021 putShort(o, offset + 0, pick(i0, i3));
4022 putShort(o, offset + 2, pick(i1, i2));
4023 putShort(o, offset + 4, pick(i2, i1));
4024 putShort(o, offset + 6, pick(i3, i0));
4025 }
4026 private void putLongParts(Object o, long offset, int i0, int i1) {
4027 putInt(o, offset + 0, pick(i0, i1));
4028 putInt(o, offset + 4, pick(i1, i0));
4029 }
4030 private void putIntParts(Object o, long offset, short i0, short i1) {
4031 putShort(o, offset + 0, pick(i0, i1));
4032 putShort(o, offset + 2, pick(i1, i0));
4033 }
4034 private void putIntParts(Object o, long offset, byte i0, byte i1, byte i2, byte i3) {
4035 putByte(o, offset + 0, pick(i0, i3));
4036 putByte(o, offset + 1, pick(i1, i2));
4037 putByte(o, offset + 2, pick(i2, i1));
4038 putByte(o, offset + 3, pick(i3, i0));
4039 }
4040 private void putShortParts(Object o, long offset, byte i0, byte i1) {
4041 putByte(o, offset + 0, pick(i0, i1));
4042 putByte(o, offset + 1, pick(i1, i0));
4043 }
4044
4045 // Zero-extend an integer
4046 private static int toUnsignedInt(byte n) { return n & 0xff; }
4047 private static int toUnsignedInt(short n) { return n & 0xffff; }
4048 private static long toUnsignedLong(byte n) { return n & 0xffl; }
4049 private static long toUnsignedLong(short n) { return n & 0xffffl; }
4050 private static long toUnsignedLong(int n) { return n & 0xffffffffl; }
4051
4052 // Maybe byte-reverse an integer
4053 private static char convEndian(boolean big, char n) { return big == BIG_ENDIAN ? n : Character.reverseBytes(n); }
4054 private static short convEndian(boolean big, short n) { return big == BIG_ENDIAN ? n : Short.reverseBytes(n) ; }
4055 private static int convEndian(boolean big, int n) { return big == BIG_ENDIAN ? n : Integer.reverseBytes(n) ; }
4056 private static long convEndian(boolean big, long n) { return big == BIG_ENDIAN ? n : Long.reverseBytes(n) ; }
4057
4058
4059
4060 private native long allocateMemory0(long bytes);
4061 private native long reallocateMemory0(long address, long bytes);
4062 private native void freeMemory0(long address);
4063 private native void setMemory0(Object o, long offset, long bytes, byte value);
4064 @HotSpotIntrinsicCandidate
4065 private native void copyMemory0(Object srcBase, long srcOffset, Object destBase, long destOffset, long bytes);
4066 private native void copySwapMemory0(Object srcBase, long srcOffset, Object destBase, long destOffset, long bytes, long elemSize);
4067 private native long objectFieldOffset0(Field f);
4068 private native long objectFieldOffset1(Class<?> c, String name);
4069 private native long staticFieldOffset0(Field f);
4070 private native Object staticFieldBase0(Field f);
4071 private native boolean shouldBeInitialized0(Class<?> c);
4072 private native void ensureClassInitialized0(Class<?> c);
4073 private native int arrayBaseOffset0(Class<?> arrayClass);
4074 private native int arrayIndexScale0(Class<?> arrayClass);
4075 private native Class<?> defineAnonymousClass0(Class<?> hostClass, byte[] data, Object[] cpPatches);
4076 private native int getLoadAverage0(double[] loadavg, int nelems);
4077
4078
4079 /**
4080 * Invokes the given direct byte buffer's cleaner, if any.
4081 *
4082 * @param directBuffer a direct byte buffer
4083 * @throws NullPointerException if {@code directBuffer} is null
4084 * @throws IllegalArgumentException if {@code directBuffer} is non-direct,
4085 * or is a {@link java.nio.Buffer#slice slice}, or is a
4086 * {@link java.nio.Buffer#duplicate duplicate}
4087 */
4088 public void invokeCleaner(java.nio.ByteBuffer directBuffer) {
4089 if (!directBuffer.isDirect())
4090 throw new IllegalArgumentException("buffer is non-direct");
4091
4092 DirectBuffer db = (DirectBuffer) directBuffer;
4093 if (db.attachment() != null)
4094 throw new IllegalArgumentException("duplicate or slice");
4095
4096 Cleaner cleaner = db.cleaner();
4097 if (cleaner != null) {
4098 cleaner.clean();
4099 }
4100 }
4101
4102 // The following deprecated methods are used by JSR 166.
4103
4104 @Deprecated(since="12", forRemoval=true)
4105 public final Object getObject(Object o, long offset) {
4106 return getReference(o, offset);
4107 }
4108 @Deprecated(since="12", forRemoval=true)
4109 public final Object getObjectVolatile(Object o, long offset) {
4110 return getReferenceVolatile(o, offset);
4111 }
4112 @Deprecated(since="12", forRemoval=true)
4113 public final Object getObjectAcquire(Object o, long offset) {
4114 return getReferenceAcquire(o, offset);
4115 }
4116 @Deprecated(since="12", forRemoval=true)
4117 public final Object getObjectOpaque(Object o, long offset) {
4118 return getReferenceOpaque(o, offset);
4119 }
4120
4121
4122 @Deprecated(since="12", forRemoval=true)
4123 public final void putObject(Object o, long offset, Object x) {
4124 putReference(o, offset, x);
4125 }
4126 @Deprecated(since="12", forRemoval=true)
4127 public final void putObjectVolatile(Object o, long offset, Object x) {
4128 putReferenceVolatile(o, offset, x);
4129 }
4130 @Deprecated(since="12", forRemoval=true)
4131 public final void putObjectOpaque(Object o, long offset, Object x) {
4132 putReferenceOpaque(o, offset, x);
4133 }
4134 @Deprecated(since="12", forRemoval=true)
4135 public final void putObjectRelease(Object o, long offset, Object x) {
4136 putReferenceRelease(o, offset, x);
4137 }
4138
4139
4140 @Deprecated(since="12", forRemoval=true)
4141 public final Object getAndSetObject(Object o, long offset, Object newValue) {
4142 return getAndSetReference(o, offset, newValue);
4143 }
4144 @Deprecated(since="12", forRemoval=true)
4145 public final Object getAndSetObjectAcquire(Object o, long offset, Object newValue) {
4146 return getAndSetReferenceAcquire(o, offset, newValue);
4147 }
4148 @Deprecated(since="12", forRemoval=true)
4149 public final Object getAndSetObjectRelease(Object o, long offset, Object newValue) {
4150 return getAndSetReferenceRelease(o, offset, newValue);
4151 }
4152
4153
4154 @Deprecated(since="12", forRemoval=true)
4155 public final boolean compareAndSetObject(Object o, long offset, Object expected, Object x) {
4156 return compareAndSetReference(o, offset, expected, x);
4157 }
4158 @Deprecated(since="12", forRemoval=true)
4159 public final Object compareAndExchangeObject(Object o, long offset, Object expected, Object x) {
4160 return compareAndExchangeReference(o, offset, expected, x);
4161 }
4162 @Deprecated(since="12", forRemoval=true)
4163 public final Object compareAndExchangeObjectAcquire(Object o, long offset, Object expected, Object x) {
4164 return compareAndExchangeReferenceAcquire(o, offset, expected, x);
4165 }
4166 @Deprecated(since="12", forRemoval=true)
4167 public final Object compareAndExchangeObjectRelease(Object o, long offset, Object expected, Object x) {
4168 return compareAndExchangeReferenceRelease(o, offset, expected, x);
4169 }
4170
4171
4172 @Deprecated(since="12", forRemoval=true)
4173 public final boolean weakCompareAndSetObject(Object o, long offset, Object expected, Object x) {
4174 return weakCompareAndSetReference(o, offset, expected, x);
4175 }
4176 @Deprecated(since="12", forRemoval=true)
4177 public final boolean weakCompareAndSetObjectAcquire(Object o, long offset, Object expected, Object x) {
4178 return weakCompareAndSetReferenceAcquire(o, offset, expected, x);
4179 }
4180 @Deprecated(since="12", forRemoval=true)
4181 public final boolean weakCompareAndSetObjectPlain(Object o, long offset, Object expected, Object x) {
4182 return weakCompareAndSetReferencePlain(o, offset, expected, x);
4183 }
4184 @Deprecated(since="12", forRemoval=true)
4185 public final boolean weakCompareAndSetObjectRelease(Object o, long offset, Object expected, Object x) {
4186 return weakCompareAndSetReferenceRelease(o, offset, expected, x);
4187 }
4188 }