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 /**
1045 * Ensure writeback of a specified virtual memory address range
1046 * from cache to physical memory. All bytes in the address range
1047 * are guaranteed to have been written back to physical memory on
1048 * return from this call i.e. subsequently executed store
1049 * instructions are guaranteed not to be visible before the
1050 * writeback is completed.
1051 *
1052 * @param address
1053 * the lowest byte address that must be guaranteed written
1054 * back to memory. bytes at lower addresses may also be
1055 * written back.
1056 *
1057 * @param length
1058 * the length in bytes of the region starting at address
1059 * that must be guaranteed written back to memory.
1060 *
1061 * @throws RuntimeException if memory writeback is not supported
1062 * on the current hardware of if the arguments are invalid.
1063 * (<em>Note:</em> after optimization, invalid inputs may
1064 * go undetected, which will lead to unpredictable
1065 * behavior)
1066 *
1067 * @since 14
1068 */
1069
1070 public void writebackMemory(long address, long length) {
1071 checkWritebackEnabled();
1072 checkWritebackMemory(address, length);
1073
1074 // perform any required pre-writeback barrier
1075 writebackPreSync0();
1076
1077 // write back one cache line at a time
1078 long line = dataCacheLineAlignDown(address);
1079 long end = address + length;
1080 while (line < end) {
1081 writeback0(line);
1082 line += dataCacheLineFlushSize();
1083 }
1084
1085 // perform any required post-writeback barrier
1086 writebackPostSync0();
1087 }
1088
1089 /**
1090 * Validate the arguments to writebackMemory
1091 *
1092 * @throws RuntimeException if the arguments are invalid
1093 * (<em>Note:</em> after optimization, invalid inputs may
1094 * go undetected, which will lead to unpredictable
1095 * behavior)
1096 */
1097 private void checkWritebackMemory(long address, long length) {
1098 checkNativeAddress(address);
1099 checkSize(length);
1100 }
1101
1102 /**
1103 * Validate that the current hardware supports memory writeback.
1104 * (<em>Note:</em> this is a belt and braces check. Clients are
1105 * expected to test whether writeback is enabled by calling
1106 * ({@link isWritebackEnabled #isWritebackEnabled} and avoid
1107 * calling method {@link writeback #writeback} if it is disabled).
1108 *
1109 *
1110 * @throws RuntimeException if memory writeback is not supported
1111 */
1112 private void checkWritebackEnabled() {
1113 if (!isWritebackEnabled()) {
1114 throw new RuntimeException("writebackMemory not enabled!");
1115 }
1116 }
1117
1118 /**
1119 * force writeback of an individual cache line.
1120 *
1121 * @param address
1122 * the start address of the cache line to be written back
1123 */
1124 @HotSpotIntrinsicCandidate
1125 private native void writeback0(long address);
1126
1127 /**
1128 * Serialize writeback operations relative to preceding memory writes.
1129 */
1130 @HotSpotIntrinsicCandidate
1131 private native void writebackPreSync0();
1132
1133 /**
1134 * Serialize writeback operations relative to following memory writes.
1135 */
1136 @HotSpotIntrinsicCandidate
1137 private native void writebackPostSync0();
1138
1139 /// random queries
1140
1141 /**
1142 * This constant differs from all results that will ever be returned from
1143 * {@link #staticFieldOffset}, {@link #objectFieldOffset},
1144 * or {@link #arrayBaseOffset}.
1145 */
1146 public static final int INVALID_FIELD_OFFSET = -1;
1147
1148 /**
1149 * Reports the location of a given field in the storage allocation of its
1150 * class. Do not expect to perform any sort of arithmetic on this offset;
1151 * it is just a cookie which is passed to the unsafe heap memory accessors.
1152 *
1153 * <p>Any given field will always have the same offset and base, and no
1154 * two distinct fields of the same class will ever have the same offset
1155 * and base.
1156 *
1157 * <p>As of 1.4.1, offsets for fields are represented as long values,
1158 * although the Sun JVM does not use the most significant 32 bits.
1159 * However, JVM implementations which store static fields at absolute
1160 * addresses can use long offsets and null base pointers to express
1161 * the field locations in a form usable by {@link #getInt(Object,long)}.
1162 * Therefore, code which will be ported to such JVMs on 64-bit platforms
1163 * must preserve all bits of static field offsets.
1164 * @see #getInt(Object, long)
1165 */
1166 public long objectFieldOffset(Field f) {
1167 if (f == null) {
1168 throw new NullPointerException();
1169 }
1170
1171 return objectFieldOffset0(f);
1172 }
1173
1174 /**
1175 * Reports the location of the field with a given name in the storage
1176 * allocation of its class.
1177 *
1178 * @throws NullPointerException if any parameter is {@code null}.
1179 * @throws InternalError if there is no field named {@code name} declared
1180 * in class {@code c}, i.e., if {@code c.getDeclaredField(name)}
1181 * would throw {@code java.lang.NoSuchFieldException}.
1182 *
1183 * @see #objectFieldOffset(Field)
1184 */
1185 public long objectFieldOffset(Class<?> c, String name) {
1186 if (c == null || name == null) {
1187 throw new NullPointerException();
1188 }
1189
1190 return objectFieldOffset1(c, name);
1191 }
1192
1193 /**
1194 * Reports the location of a given static field, in conjunction with {@link
1195 * #staticFieldBase}.
1196 * <p>Do not expect to perform any sort of arithmetic on this offset;
1197 * it is just a cookie which is passed to the unsafe heap memory accessors.
1198 *
1199 * <p>Any given field will always have the same offset, and no two distinct
1200 * fields of the same class will ever have the same offset.
1201 *
1202 * <p>As of 1.4.1, offsets for fields are represented as long values,
1203 * although the Sun JVM does not use the most significant 32 bits.
1204 * It is hard to imagine a JVM technology which needs more than
1205 * a few bits to encode an offset within a non-array object,
1206 * However, for consistency with other methods in this class,
1207 * this method reports its result as a long value.
1208 * @see #getInt(Object, long)
1209 */
1210 public long staticFieldOffset(Field f) {
1211 if (f == null) {
1212 throw new NullPointerException();
1213 }
1214
1215 return staticFieldOffset0(f);
1216 }
1217
1218 /**
1219 * Reports the location of a given static field, in conjunction with {@link
1220 * #staticFieldOffset}.
1221 * <p>Fetch the base "Object", if any, with which static fields of the
1222 * given class can be accessed via methods like {@link #getInt(Object,
1223 * long)}. This value may be null. This value may refer to an object
1224 * which is a "cookie", not guaranteed to be a real Object, and it should
1225 * not be used in any way except as argument to the get and put routines in
1226 * this class.
1227 */
1228 public Object staticFieldBase(Field f) {
1229 if (f == null) {
1230 throw new NullPointerException();
1231 }
1232
1233 return staticFieldBase0(f);
1234 }
1235
1236 /**
1237 * Detects if the given class may need to be initialized. This is often
1238 * needed in conjunction with obtaining the static field base of a
1239 * class.
1240 * @return false only if a call to {@code ensureClassInitialized} would have no effect
1241 */
1242 public boolean shouldBeInitialized(Class<?> c) {
1243 if (c == null) {
1244 throw new NullPointerException();
1245 }
1246
1247 return shouldBeInitialized0(c);
1248 }
1249
1250 /**
1251 * Ensures the given class has been initialized. This is often
1252 * needed in conjunction with obtaining the static field base of a
1253 * class.
1254 */
1255 public void ensureClassInitialized(Class<?> c) {
1256 if (c == null) {
1257 throw new NullPointerException();
1258 }
1259
1260 ensureClassInitialized0(c);
1261 }
1262
1263 /**
1264 * Reports the offset of the first element in the storage allocation of a
1265 * given array class. If {@link #arrayIndexScale} returns a non-zero value
1266 * for the same class, you may use that scale factor, together with this
1267 * base offset, to form new offsets to access elements of arrays of the
1268 * given class.
1269 *
1270 * @see #getInt(Object, long)
1271 * @see #putInt(Object, long, int)
1272 */
1273 public int arrayBaseOffset(Class<?> arrayClass) {
1274 if (arrayClass == null) {
1275 throw new NullPointerException();
1276 }
1277
1278 return arrayBaseOffset0(arrayClass);
1279 }
1280
1281
1282 /** The value of {@code arrayBaseOffset(boolean[].class)} */
1283 public static final int ARRAY_BOOLEAN_BASE_OFFSET
1284 = theUnsafe.arrayBaseOffset(boolean[].class);
1285
1286 /** The value of {@code arrayBaseOffset(byte[].class)} */
1287 public static final int ARRAY_BYTE_BASE_OFFSET
1288 = theUnsafe.arrayBaseOffset(byte[].class);
1289
1290 /** The value of {@code arrayBaseOffset(short[].class)} */
1291 public static final int ARRAY_SHORT_BASE_OFFSET
1292 = theUnsafe.arrayBaseOffset(short[].class);
1293
1294 /** The value of {@code arrayBaseOffset(char[].class)} */
1295 public static final int ARRAY_CHAR_BASE_OFFSET
1296 = theUnsafe.arrayBaseOffset(char[].class);
1297
1298 /** The value of {@code arrayBaseOffset(int[].class)} */
1299 public static final int ARRAY_INT_BASE_OFFSET
1300 = theUnsafe.arrayBaseOffset(int[].class);
1301
1302 /** The value of {@code arrayBaseOffset(long[].class)} */
1303 public static final int ARRAY_LONG_BASE_OFFSET
1304 = theUnsafe.arrayBaseOffset(long[].class);
1305
1306 /** The value of {@code arrayBaseOffset(float[].class)} */
1307 public static final int ARRAY_FLOAT_BASE_OFFSET
1308 = theUnsafe.arrayBaseOffset(float[].class);
1309
1310 /** The value of {@code arrayBaseOffset(double[].class)} */
1311 public static final int ARRAY_DOUBLE_BASE_OFFSET
1312 = theUnsafe.arrayBaseOffset(double[].class);
1313
1314 /** The value of {@code arrayBaseOffset(Object[].class)} */
1315 public static final int ARRAY_OBJECT_BASE_OFFSET
1316 = theUnsafe.arrayBaseOffset(Object[].class);
1317
1318 /**
1319 * Reports the scale factor for addressing elements in the storage
1320 * allocation of a given array class. However, arrays of "narrow" types
1321 * will generally not work properly with accessors like {@link
1322 * #getByte(Object, long)}, so the scale factor for such classes is reported
1323 * as zero.
1324 *
1325 * @see #arrayBaseOffset
1326 * @see #getInt(Object, long)
1327 * @see #putInt(Object, long, int)
1328 */
1329 public int arrayIndexScale(Class<?> arrayClass) {
1330 if (arrayClass == null) {
1331 throw new NullPointerException();
1332 }
1333
1334 return arrayIndexScale0(arrayClass);
1335 }
1336
1337 /**
1338 * Return the size of the object in the heap.
1339 * @param o an object
1340 * @return the objects's size
1341 * @since Valhalla
1342 */
1343 public long getObjectSize(Object o) {
1344 if (o == null)
1345 throw new NullPointerException();
1346 return getObjectSize0(o);
1347 }
1348
1349 /** The value of {@code arrayIndexScale(boolean[].class)} */
1350 public static final int ARRAY_BOOLEAN_INDEX_SCALE
1351 = theUnsafe.arrayIndexScale(boolean[].class);
1352
1353 /** The value of {@code arrayIndexScale(byte[].class)} */
1354 public static final int ARRAY_BYTE_INDEX_SCALE
1355 = theUnsafe.arrayIndexScale(byte[].class);
1356
1357 /** The value of {@code arrayIndexScale(short[].class)} */
1358 public static final int ARRAY_SHORT_INDEX_SCALE
1359 = theUnsafe.arrayIndexScale(short[].class);
1360
1361 /** The value of {@code arrayIndexScale(char[].class)} */
1362 public static final int ARRAY_CHAR_INDEX_SCALE
1363 = theUnsafe.arrayIndexScale(char[].class);
1364
1365 /** The value of {@code arrayIndexScale(int[].class)} */
1366 public static final int ARRAY_INT_INDEX_SCALE
1367 = theUnsafe.arrayIndexScale(int[].class);
1368
1369 /** The value of {@code arrayIndexScale(long[].class)} */
1370 public static final int ARRAY_LONG_INDEX_SCALE
1371 = theUnsafe.arrayIndexScale(long[].class);
1372
1373 /** The value of {@code arrayIndexScale(float[].class)} */
1374 public static final int ARRAY_FLOAT_INDEX_SCALE
1375 = theUnsafe.arrayIndexScale(float[].class);
1376
1377 /** The value of {@code arrayIndexScale(double[].class)} */
1378 public static final int ARRAY_DOUBLE_INDEX_SCALE
1379 = theUnsafe.arrayIndexScale(double[].class);
1380
1381 /** The value of {@code arrayIndexScale(Object[].class)} */
1382 public static final int ARRAY_OBJECT_INDEX_SCALE
1383 = theUnsafe.arrayIndexScale(Object[].class);
1384
1385 /**
1386 * Reports the size in bytes of a native pointer, as stored via {@link
1387 * #putAddress}. This value will be either 4 or 8. Note that the sizes of
1388 * other primitive types (as stored in native memory blocks) is determined
1389 * fully by their information content.
1390 */
1391 public int addressSize() {
1392 return ADDRESS_SIZE;
1393 }
1394
1395 /** The value of {@code addressSize()} */
1396 public static final int ADDRESS_SIZE = ADDRESS_SIZE0;
1397
1398 /**
1399 * Reports the size in bytes of a native memory page (whatever that is).
1400 * This value will always be a power of two.
1401 */
1402 public int pageSize() { return PAGE_SIZE; }
1403
1404 /**
1405 * Reports the size in bytes of a data cache line written back by
1406 * the hardware cache line flush operation available to the JVM or
1407 * 0 if data cache line flushing is not enabled.
1408 */
1409 public int dataCacheLineFlushSize() { return DATA_CACHE_LINE_FLUSH_SIZE; }
1410
1411 /**
1412 * Rounds down address to a data cache line boundary as
1413 * determined by {@link #dataCacheLineFlushSize}
1414 * @return the rounded down address
1415 */
1416 public long dataCacheLineAlignDown(long address) {
1417 return (address & ~(DATA_CACHE_LINE_FLUSH_SIZE - 1));
1418 }
1419
1420 /**
1421 * Returns true if data cache line writeback
1422 */
1423 public static boolean isWritebackEnabled() { return DATA_CACHE_LINE_FLUSH_SIZE != 0; }
1424
1425 /// random trusted operations from JNI:
1426
1427 /**
1428 * Tells the VM to define a class, without security checks. By default, the
1429 * class loader and protection domain come from the caller's class.
1430 */
1431 public Class<?> defineClass(String name, byte[] b, int off, int len,
1432 ClassLoader loader,
1433 ProtectionDomain protectionDomain) {
1434 if (b == null) {
1435 throw new NullPointerException();
1436 }
1437 if (len < 0) {
1438 throw new ArrayIndexOutOfBoundsException();
1439 }
1440
1441 return defineClass0(name, b, off, len, loader, protectionDomain);
1442 }
1443
1444 public native Class<?> defineClass0(String name, byte[] b, int off, int len,
1445 ClassLoader loader,
1446 ProtectionDomain protectionDomain);
1447
1448 /**
1449 * Defines a class but does not make it known to the class loader or system dictionary.
1450 * <p>
1451 * For each CP entry, the corresponding CP patch must either be null or have
1452 * the a format that matches its tag:
1453 * <ul>
1454 * <li>Integer, Long, Float, Double: the corresponding wrapper object type from java.lang
1455 * <li>Utf8: a string (must have suitable syntax if used as signature or name)
1456 * <li>Class: any java.lang.Class object
1457 * <li>String: any object (not just a java.lang.String)
1458 * <li>InterfaceMethodRef: (NYI) a method handle to invoke on that call site's arguments
1459 * </ul>
1460 * @param hostClass context for linkage, access control, protection domain, and class loader
1461 * @param data bytes of a class file
1462 * @param cpPatches where non-null entries exist, they replace corresponding CP entries in data
1463 */
1464 public Class<?> defineAnonymousClass(Class<?> hostClass, byte[] data, Object[] cpPatches) {
1465 if (hostClass == null || data == null) {
1466 throw new NullPointerException();
1467 }
1468 if (hostClass.isArray() || hostClass.isPrimitive()) {
1469 throw new IllegalArgumentException();
1470 }
1471
1472 return defineAnonymousClass0(hostClass, data, cpPatches);
1473 }
1474
1475 /**
1476 * Allocates an instance but does not run any constructor.
1477 * Initializes the class if it has not yet been.
1478 */
1479 @HotSpotIntrinsicCandidate
1480 public native Object allocateInstance(Class<?> cls)
1481 throws InstantiationException;
1482
1483 /**
1484 * Allocates an array of a given type, but does not do zeroing.
1485 * <p>
1486 * This method should only be used in the very rare cases where a high-performance code
1487 * overwrites the destination array completely, and compilers cannot assist in zeroing elimination.
1488 * In an overwhelming majority of cases, a normal Java allocation should be used instead.
1489 * <p>
1490 * Users of this method are <b>required</b> to overwrite the initial (garbage) array contents
1491 * before allowing untrusted code, or code in other threads, to observe the reference
1492 * to the newly allocated array. In addition, the publication of the array reference must be
1493 * safe according to the Java Memory Model requirements.
1494 * <p>
1495 * The safest approach to deal with an uninitialized array is to keep the reference to it in local
1496 * variable at least until the initialization is complete, and then publish it <b>once</b>, either
1497 * by writing it to a <em>volatile</em> field, or storing it into a <em>final</em> field in constructor,
1498 * or issuing a {@link #storeFence} before publishing the reference.
1499 * <p>
1500 * @implnote This method can only allocate primitive arrays, to avoid garbage reference
1501 * elements that could break heap integrity.
1502 *
1503 * @param componentType array component type to allocate
1504 * @param length array size to allocate
1505 * @throws IllegalArgumentException if component type is null, or not a primitive class;
1506 * or the length is negative
1507 */
1508 public Object allocateUninitializedArray(Class<?> componentType, int length) {
1509 if (componentType == null) {
1510 throw new IllegalArgumentException("Component type is null");
1511 }
1512 if (!componentType.isPrimitive()) {
1513 throw new IllegalArgumentException("Component type is not primitive");
1514 }
1515 if (length < 0) {
1516 throw new IllegalArgumentException("Negative length");
1517 }
1518 return allocateUninitializedArray0(componentType, length);
1519 }
1520
1521 @HotSpotIntrinsicCandidate
1522 private Object allocateUninitializedArray0(Class<?> componentType, int length) {
1523 // These fallbacks provide zeroed arrays, but intrinsic is not required to
1524 // return the zeroed arrays.
1525 if (componentType == byte.class) return new byte[length];
1526 if (componentType == boolean.class) return new boolean[length];
1527 if (componentType == short.class) return new short[length];
1528 if (componentType == char.class) return new char[length];
1529 if (componentType == int.class) return new int[length];
1530 if (componentType == float.class) return new float[length];
1531 if (componentType == long.class) return new long[length];
1532 if (componentType == double.class) return new double[length];
1533 return null;
1534 }
1535
1536 /** Throws the exception without telling the verifier. */
1537 public native void throwException(Throwable ee);
1538
1539 /**
1540 * Atomically updates Java variable to {@code x} if it is currently
1541 * holding {@code expected}.
1542 *
1543 * <p>This operation has memory semantics of a {@code volatile} read
1544 * and write. Corresponds to C11 atomic_compare_exchange_strong.
1545 *
1546 * @return {@code true} if successful
1547 */
1548 @HotSpotIntrinsicCandidate
1549 public final native boolean compareAndSetReference(Object o, long offset,
1550 Object expected,
1551 Object x);
1552
1553 private final boolean isInlineType(Object o) {
1554 return o != null && o.getClass().isInlineClass();
1555 }
1556
1557 /*
1558 * For inline type, CAS should do substitutability test as opposed
1559 * to two pointers comparison.
1560 *
1561 * Perhaps we can keep the xxxObject methods for compatibility and
1562 * change the JDK 13 xxxReference method signature freely.
1563 */
1564 public final <V> boolean compareAndSetReference(Object o, long offset,
1565 Class<?> valueType,
1566 V expected,
1567 V x) {
1568 if (valueType.isInlineClass() || isInlineType(expected)) {
1569 synchronized (valueLock) {
1570 Object witness = getReference(o, offset);
1571 if (witness == expected) {
1572 putReference(o, offset, x);
1573 return true;
1574 } else {
1575 return false;
1576 }
1577 }
1578 } else {
1579 return compareAndSetReference(o, offset, expected, x);
1580 }
1581 }
1582
1583 @ForceInline
1584 public final <V> boolean compareAndSetValue(Object o, long offset,
1585 Class<?> valueType,
1586 V expected,
1587 V x) {
1588 synchronized (valueLock) {
1589 Object witness = getValue(o, offset, valueType);
1590 if (witness == expected) {
1591 putValue(o, offset, valueType, x);
1592 return true;
1593 }
1594 else {
1595 return false;
1596 }
1597 }
1598 }
1599
1600 @HotSpotIntrinsicCandidate
1601 public final native Object compareAndExchangeReference(Object o, long offset,
1602 Object expected,
1603 Object x);
1604
1605 public final <V> Object compareAndExchangeReference(Object o, long offset,
1606 Class<?> valueType,
1607 V expected,
1608 V x) {
1609 if (valueType.isInlineClass() || isInlineType(expected)) {
1610 synchronized (valueLock) {
1611 Object witness = getReference(o, offset);
1612 if (witness == expected) {
1613 putReference(o, offset, x);
1614 }
1615 return witness;
1616 }
1617 } else {
1618 return compareAndExchangeReference(o, offset, expected, x);
1619 }
1620 }
1621
1622 @ForceInline
1623 public final <V> Object compareAndExchangeValue(Object o, long offset,
1624 Class<?> valueType,
1625 V expected,
1626 V x) {
1627 synchronized (valueLock) {
1628 Object witness = getValue(o, offset, valueType);
1629 if (witness == expected) {
1630 putValue(o, offset, valueType, x);
1631 }
1632 return witness;
1633 }
1634 }
1635
1636 @HotSpotIntrinsicCandidate
1637 public final Object compareAndExchangeReferenceAcquire(Object o, long offset,
1638 Object expected,
1639 Object x) {
1640 return compareAndExchangeReference(o, offset, expected, x);
1641 }
1642
1643 public final <V> Object compareAndExchangeReferenceAcquire(Object o, long offset,
1644 Class<?> valueType,
1645 V expected,
1646 V x) {
1647 return compareAndExchangeReference(o, offset, valueType, expected, x);
1648 }
1649
1650 @ForceInline
1651 public final <V> Object compareAndExchangeValueAcquire(Object o, long offset,
1652 Class<?> valueType,
1653 V expected,
1654 V x) {
1655 return compareAndExchangeValue(o, offset, valueType, expected, x);
1656 }
1657
1658 @HotSpotIntrinsicCandidate
1659 public final Object compareAndExchangeReferenceRelease(Object o, long offset,
1660 Object expected,
1661 Object x) {
1662 return compareAndExchangeReference(o, offset, expected, x);
1663 }
1664
1665 public final <V> Object compareAndExchangeReferenceRelease(Object o, long offset,
1666 Class<?> valueType,
1667 V expected,
1668 V x) {
1669 return compareAndExchangeReference(o, offset, valueType, expected, x);
1670 }
1671
1672 @ForceInline
1673 public final <V> Object compareAndExchangeValueRelease(Object o, long offset,
1674 Class<?> valueType,
1675 V expected,
1676 V x) {
1677 return compareAndExchangeValue(o, offset, valueType, expected, x);
1678 }
1679
1680 @HotSpotIntrinsicCandidate
1681 public final boolean weakCompareAndSetReferencePlain(Object o, long offset,
1682 Object expected,
1683 Object x) {
1684 return compareAndSetReference(o, offset, expected, x);
1685 }
1686
1687 public final <V> boolean weakCompareAndSetReferencePlain(Object o, long offset,
1688 Class<?> valueType,
1689 V expected,
1690 V x) {
1691 if (valueType.isInlineClass() || isInlineType(expected)) {
1692 return compareAndSetReference(o, offset, valueType, expected, x);
1693 } else {
1694 return weakCompareAndSetReferencePlain(o, offset, expected, x);
1695 }
1696 }
1697
1698 @ForceInline
1699 public final <V> boolean weakCompareAndSetValuePlain(Object o, long offset,
1700 Class<?> valueType,
1701 V expected,
1702 V x) {
1703 return compareAndSetValue(o, offset, valueType, expected, x);
1704 }
1705
1706 @HotSpotIntrinsicCandidate
1707 public final boolean weakCompareAndSetReferenceAcquire(Object o, long offset,
1708 Object expected,
1709 Object x) {
1710 return compareAndSetReference(o, offset, expected, x);
1711 }
1712
1713 public final <V> boolean weakCompareAndSetReferenceAcquire(Object o, long offset,
1714 Class<?> valueType,
1715 V expected,
1716 V x) {
1717 if (valueType.isInlineClass() || isInlineType(expected)) {
1718 return compareAndSetReference(o, offset, valueType, expected, x);
1719 } else {
1720 return weakCompareAndSetReferencePlain(o, offset, expected, x);
1721 }
1722 }
1723
1724 @ForceInline
1725 public final <V> boolean weakCompareAndSetValueAcquire(Object o, long offset,
1726 Class<?> valueType,
1727 V expected,
1728 V x) {
1729 return compareAndSetValue(o, offset, valueType, expected, x);
1730 }
1731
1732 @HotSpotIntrinsicCandidate
1733 public final boolean weakCompareAndSetReferenceRelease(Object o, long offset,
1734 Object expected,
1735 Object x) {
1736 return compareAndSetReference(o, offset, expected, x);
1737 }
1738
1739 public final <V> boolean weakCompareAndSetReferenceRelease(Object o, long offset,
1740 Class<?> valueType,
1741 V expected,
1742 V x) {
1743 if (valueType.isInlineClass() || isInlineType(expected)) {
1744 return compareAndSetReference(o, offset, valueType, expected, x);
1745 } else {
1746 return weakCompareAndSetReferencePlain(o, offset, expected, x);
1747 }
1748 }
1749
1750 @ForceInline
1751 public final <V> boolean weakCompareAndSetValueRelease(Object o, long offset,
1752 Class<?> valueType,
1753 V expected,
1754 V x) {
1755 return compareAndSetValue(o, offset, valueType, expected, x);
1756 }
1757
1758 @HotSpotIntrinsicCandidate
1759 public final boolean weakCompareAndSetReference(Object o, long offset,
1760 Object expected,
1761 Object x) {
1762 return compareAndSetReference(o, offset, expected, x);
1763 }
1764
1765 public final <V> boolean weakCompareAndSetReference(Object o, long offset,
1766 Class<?> valueType,
1767 V expected,
1768 V x) {
1769 if (valueType.isInlineClass() || isInlineType(expected)) {
1770 return compareAndSetReference(o, offset, valueType, expected, x);
1771 } else {
1772 return weakCompareAndSetReferencePlain(o, offset, expected, x);
1773 }
1774 }
1775
1776 @ForceInline
1777 public final <V> boolean weakCompareAndSetValue(Object o, long offset,
1778 Class<?> valueType,
1779 V expected,
1780 V x) {
1781 return compareAndSetValue(o, offset, valueType, expected, x);
1782 }
1783
1784 /**
1785 * Atomically updates Java variable to {@code x} if it is currently
1786 * holding {@code expected}.
1787 *
1788 * <p>This operation has memory semantics of a {@code volatile} read
1789 * and write. Corresponds to C11 atomic_compare_exchange_strong.
1790 *
1791 * @return {@code true} if successful
1792 */
1793 @HotSpotIntrinsicCandidate
1794 public final native boolean compareAndSetInt(Object o, long offset,
1795 int expected,
1796 int x);
1797
1798 @HotSpotIntrinsicCandidate
1799 public final native int compareAndExchangeInt(Object o, long offset,
1800 int expected,
1801 int x);
1802
1803 @HotSpotIntrinsicCandidate
1804 public final int compareAndExchangeIntAcquire(Object o, long offset,
1805 int expected,
1806 int x) {
1807 return compareAndExchangeInt(o, offset, expected, x);
1808 }
1809
1810 @HotSpotIntrinsicCandidate
1811 public final int compareAndExchangeIntRelease(Object o, long offset,
1812 int expected,
1813 int x) {
1814 return compareAndExchangeInt(o, offset, expected, x);
1815 }
1816
1817 @HotSpotIntrinsicCandidate
1818 public final boolean weakCompareAndSetIntPlain(Object o, long offset,
1819 int expected,
1820 int x) {
1821 return compareAndSetInt(o, offset, expected, x);
1822 }
1823
1824 @HotSpotIntrinsicCandidate
1825 public final boolean weakCompareAndSetIntAcquire(Object o, long offset,
1826 int expected,
1827 int x) {
1828 return compareAndSetInt(o, offset, expected, x);
1829 }
1830
1831 @HotSpotIntrinsicCandidate
1832 public final boolean weakCompareAndSetIntRelease(Object o, long offset,
1833 int expected,
1834 int x) {
1835 return compareAndSetInt(o, offset, expected, x);
1836 }
1837
1838 @HotSpotIntrinsicCandidate
1839 public final boolean weakCompareAndSetInt(Object o, long offset,
1840 int expected,
1841 int x) {
1842 return compareAndSetInt(o, offset, expected, x);
1843 }
1844
1845 @HotSpotIntrinsicCandidate
1846 public final byte compareAndExchangeByte(Object o, long offset,
1847 byte expected,
1848 byte x) {
1849 long wordOffset = offset & ~3;
1850 int shift = (int) (offset & 3) << 3;
1851 if (BIG_ENDIAN) {
1852 shift = 24 - shift;
1853 }
1854 int mask = 0xFF << shift;
1855 int maskedExpected = (expected & 0xFF) << shift;
1856 int maskedX = (x & 0xFF) << shift;
1857 int fullWord;
1858 do {
1859 fullWord = getIntVolatile(o, wordOffset);
1860 if ((fullWord & mask) != maskedExpected)
1861 return (byte) ((fullWord & mask) >> shift);
1862 } while (!weakCompareAndSetInt(o, wordOffset,
1863 fullWord, (fullWord & ~mask) | maskedX));
1864 return expected;
1865 }
1866
1867 @HotSpotIntrinsicCandidate
1868 public final boolean compareAndSetByte(Object o, long offset,
1869 byte expected,
1870 byte x) {
1871 return compareAndExchangeByte(o, offset, expected, x) == expected;
1872 }
1873
1874 @HotSpotIntrinsicCandidate
1875 public final boolean weakCompareAndSetByte(Object o, long offset,
1876 byte expected,
1877 byte x) {
1878 return compareAndSetByte(o, offset, expected, x);
1879 }
1880
1881 @HotSpotIntrinsicCandidate
1882 public final boolean weakCompareAndSetByteAcquire(Object o, long offset,
1883 byte expected,
1884 byte x) {
1885 return weakCompareAndSetByte(o, offset, expected, x);
1886 }
1887
1888 @HotSpotIntrinsicCandidate
1889 public final boolean weakCompareAndSetByteRelease(Object o, long offset,
1890 byte expected,
1891 byte x) {
1892 return weakCompareAndSetByte(o, offset, expected, x);
1893 }
1894
1895 @HotSpotIntrinsicCandidate
1896 public final boolean weakCompareAndSetBytePlain(Object o, long offset,
1897 byte expected,
1898 byte x) {
1899 return weakCompareAndSetByte(o, offset, expected, x);
1900 }
1901
1902 @HotSpotIntrinsicCandidate
1903 public final byte compareAndExchangeByteAcquire(Object o, long offset,
1904 byte expected,
1905 byte x) {
1906 return compareAndExchangeByte(o, offset, expected, x);
1907 }
1908
1909 @HotSpotIntrinsicCandidate
1910 public final byte compareAndExchangeByteRelease(Object o, long offset,
1911 byte expected,
1912 byte x) {
1913 return compareAndExchangeByte(o, offset, expected, x);
1914 }
1915
1916 @HotSpotIntrinsicCandidate
1917 public final short compareAndExchangeShort(Object o, long offset,
1918 short expected,
1919 short x) {
1920 if ((offset & 3) == 3) {
1921 throw new IllegalArgumentException("Update spans the word, not supported");
1922 }
1923 long wordOffset = offset & ~3;
1924 int shift = (int) (offset & 3) << 3;
1925 if (BIG_ENDIAN) {
1926 shift = 16 - shift;
1927 }
1928 int mask = 0xFFFF << shift;
1929 int maskedExpected = (expected & 0xFFFF) << shift;
1930 int maskedX = (x & 0xFFFF) << shift;
1931 int fullWord;
1932 do {
1933 fullWord = getIntVolatile(o, wordOffset);
1934 if ((fullWord & mask) != maskedExpected) {
1935 return (short) ((fullWord & mask) >> shift);
1936 }
1937 } while (!weakCompareAndSetInt(o, wordOffset,
1938 fullWord, (fullWord & ~mask) | maskedX));
1939 return expected;
1940 }
1941
1942 @HotSpotIntrinsicCandidate
1943 public final boolean compareAndSetShort(Object o, long offset,
1944 short expected,
1945 short x) {
1946 return compareAndExchangeShort(o, offset, expected, x) == expected;
1947 }
1948
1949 @HotSpotIntrinsicCandidate
1950 public final boolean weakCompareAndSetShort(Object o, long offset,
1951 short expected,
1952 short x) {
1953 return compareAndSetShort(o, offset, expected, x);
1954 }
1955
1956 @HotSpotIntrinsicCandidate
1957 public final boolean weakCompareAndSetShortAcquire(Object o, long offset,
1958 short expected,
1959 short x) {
1960 return weakCompareAndSetShort(o, offset, expected, x);
1961 }
1962
1963 @HotSpotIntrinsicCandidate
1964 public final boolean weakCompareAndSetShortRelease(Object o, long offset,
1965 short expected,
1966 short x) {
1967 return weakCompareAndSetShort(o, offset, expected, x);
1968 }
1969
1970 @HotSpotIntrinsicCandidate
1971 public final boolean weakCompareAndSetShortPlain(Object o, long offset,
1972 short expected,
1973 short x) {
1974 return weakCompareAndSetShort(o, offset, expected, x);
1975 }
1976
1977
1978 @HotSpotIntrinsicCandidate
1979 public final short compareAndExchangeShortAcquire(Object o, long offset,
1980 short expected,
1981 short x) {
1982 return compareAndExchangeShort(o, offset, expected, x);
1983 }
1984
1985 @HotSpotIntrinsicCandidate
1986 public final short compareAndExchangeShortRelease(Object o, long offset,
1987 short expected,
1988 short x) {
1989 return compareAndExchangeShort(o, offset, expected, x);
1990 }
1991
1992 @ForceInline
1993 private char s2c(short s) {
1994 return (char) s;
1995 }
1996
1997 @ForceInline
1998 private short c2s(char s) {
1999 return (short) s;
2000 }
2001
2002 @ForceInline
2003 public final boolean compareAndSetChar(Object o, long offset,
2004 char expected,
2005 char x) {
2006 return compareAndSetShort(o, offset, c2s(expected), c2s(x));
2007 }
2008
2009 @ForceInline
2010 public final char compareAndExchangeChar(Object o, long offset,
2011 char expected,
2012 char x) {
2013 return s2c(compareAndExchangeShort(o, offset, c2s(expected), c2s(x)));
2014 }
2015
2016 @ForceInline
2017 public final char compareAndExchangeCharAcquire(Object o, long offset,
2018 char expected,
2019 char x) {
2020 return s2c(compareAndExchangeShortAcquire(o, offset, c2s(expected), c2s(x)));
2021 }
2022
2023 @ForceInline
2024 public final char compareAndExchangeCharRelease(Object o, long offset,
2025 char expected,
2026 char x) {
2027 return s2c(compareAndExchangeShortRelease(o, offset, c2s(expected), c2s(x)));
2028 }
2029
2030 @ForceInline
2031 public final boolean weakCompareAndSetChar(Object o, long offset,
2032 char expected,
2033 char x) {
2034 return weakCompareAndSetShort(o, offset, c2s(expected), c2s(x));
2035 }
2036
2037 @ForceInline
2038 public final boolean weakCompareAndSetCharAcquire(Object o, long offset,
2039 char expected,
2040 char x) {
2041 return weakCompareAndSetShortAcquire(o, offset, c2s(expected), c2s(x));
2042 }
2043
2044 @ForceInline
2045 public final boolean weakCompareAndSetCharRelease(Object o, long offset,
2046 char expected,
2047 char x) {
2048 return weakCompareAndSetShortRelease(o, offset, c2s(expected), c2s(x));
2049 }
2050
2051 @ForceInline
2052 public final boolean weakCompareAndSetCharPlain(Object o, long offset,
2053 char expected,
2054 char x) {
2055 return weakCompareAndSetShortPlain(o, offset, c2s(expected), c2s(x));
2056 }
2057
2058 /**
2059 * The JVM converts integral values to boolean values using two
2060 * different conventions, byte testing against zero and truncation
2061 * to least-significant bit.
2062 *
2063 * <p>The JNI documents specify that, at least for returning
2064 * values from native methods, a Java boolean value is converted
2065 * to the value-set 0..1 by first truncating to a byte (0..255 or
2066 * maybe -128..127) and then testing against zero. Thus, Java
2067 * booleans in non-Java data structures are by convention
2068 * represented as 8-bit containers containing either zero (for
2069 * false) or any non-zero value (for true).
2070 *
2071 * <p>Java booleans in the heap are also stored in bytes, but are
2072 * strongly normalized to the value-set 0..1 (i.e., they are
2073 * truncated to the least-significant bit).
2074 *
2075 * <p>The main reason for having different conventions for
2076 * conversion is performance: Truncation to the least-significant
2077 * bit can be usually implemented with fewer (machine)
2078 * instructions than byte testing against zero.
2079 *
2080 * <p>A number of Unsafe methods load boolean values from the heap
2081 * as bytes. Unsafe converts those values according to the JNI
2082 * rules (i.e, using the "testing against zero" convention). The
2083 * method {@code byte2bool} implements that conversion.
2084 *
2085 * @param b the byte to be converted to boolean
2086 * @return the result of the conversion
2087 */
2088 @ForceInline
2089 private boolean byte2bool(byte b) {
2090 return b != 0;
2091 }
2092
2093 /**
2094 * Convert a boolean value to a byte. The return value is strongly
2095 * normalized to the value-set 0..1 (i.e., the value is truncated
2096 * to the least-significant bit). See {@link #byte2bool(byte)} for
2097 * more details on conversion conventions.
2098 *
2099 * @param b the boolean to be converted to byte (and then normalized)
2100 * @return the result of the conversion
2101 */
2102 @ForceInline
2103 private byte bool2byte(boolean b) {
2104 return b ? (byte)1 : (byte)0;
2105 }
2106
2107 @ForceInline
2108 public final boolean compareAndSetBoolean(Object o, long offset,
2109 boolean expected,
2110 boolean x) {
2111 return compareAndSetByte(o, offset, bool2byte(expected), bool2byte(x));
2112 }
2113
2114 @ForceInline
2115 public final boolean compareAndExchangeBoolean(Object o, long offset,
2116 boolean expected,
2117 boolean x) {
2118 return byte2bool(compareAndExchangeByte(o, offset, bool2byte(expected), bool2byte(x)));
2119 }
2120
2121 @ForceInline
2122 public final boolean compareAndExchangeBooleanAcquire(Object o, long offset,
2123 boolean expected,
2124 boolean x) {
2125 return byte2bool(compareAndExchangeByteAcquire(o, offset, bool2byte(expected), bool2byte(x)));
2126 }
2127
2128 @ForceInline
2129 public final boolean compareAndExchangeBooleanRelease(Object o, long offset,
2130 boolean expected,
2131 boolean x) {
2132 return byte2bool(compareAndExchangeByteRelease(o, offset, bool2byte(expected), bool2byte(x)));
2133 }
2134
2135 @ForceInline
2136 public final boolean weakCompareAndSetBoolean(Object o, long offset,
2137 boolean expected,
2138 boolean x) {
2139 return weakCompareAndSetByte(o, offset, bool2byte(expected), bool2byte(x));
2140 }
2141
2142 @ForceInline
2143 public final boolean weakCompareAndSetBooleanAcquire(Object o, long offset,
2144 boolean expected,
2145 boolean x) {
2146 return weakCompareAndSetByteAcquire(o, offset, bool2byte(expected), bool2byte(x));
2147 }
2148
2149 @ForceInline
2150 public final boolean weakCompareAndSetBooleanRelease(Object o, long offset,
2151 boolean expected,
2152 boolean x) {
2153 return weakCompareAndSetByteRelease(o, offset, bool2byte(expected), bool2byte(x));
2154 }
2155
2156 @ForceInline
2157 public final boolean weakCompareAndSetBooleanPlain(Object o, long offset,
2158 boolean expected,
2159 boolean x) {
2160 return weakCompareAndSetBytePlain(o, offset, bool2byte(expected), bool2byte(x));
2161 }
2162
2163 /**
2164 * Atomically updates Java variable to {@code x} if it is currently
2165 * holding {@code expected}.
2166 *
2167 * <p>This operation has memory semantics of a {@code volatile} read
2168 * and write. Corresponds to C11 atomic_compare_exchange_strong.
2169 *
2170 * @return {@code true} if successful
2171 */
2172 @ForceInline
2173 public final boolean compareAndSetFloat(Object o, long offset,
2174 float expected,
2175 float x) {
2176 return compareAndSetInt(o, offset,
2177 Float.floatToRawIntBits(expected),
2178 Float.floatToRawIntBits(x));
2179 }
2180
2181 @ForceInline
2182 public final float compareAndExchangeFloat(Object o, long offset,
2183 float expected,
2184 float x) {
2185 int w = compareAndExchangeInt(o, offset,
2186 Float.floatToRawIntBits(expected),
2187 Float.floatToRawIntBits(x));
2188 return Float.intBitsToFloat(w);
2189 }
2190
2191 @ForceInline
2192 public final float compareAndExchangeFloatAcquire(Object o, long offset,
2193 float expected,
2194 float x) {
2195 int w = compareAndExchangeIntAcquire(o, offset,
2196 Float.floatToRawIntBits(expected),
2197 Float.floatToRawIntBits(x));
2198 return Float.intBitsToFloat(w);
2199 }
2200
2201 @ForceInline
2202 public final float compareAndExchangeFloatRelease(Object o, long offset,
2203 float expected,
2204 float x) {
2205 int w = compareAndExchangeIntRelease(o, offset,
2206 Float.floatToRawIntBits(expected),
2207 Float.floatToRawIntBits(x));
2208 return Float.intBitsToFloat(w);
2209 }
2210
2211 @ForceInline
2212 public final boolean weakCompareAndSetFloatPlain(Object o, long offset,
2213 float expected,
2214 float x) {
2215 return weakCompareAndSetIntPlain(o, offset,
2216 Float.floatToRawIntBits(expected),
2217 Float.floatToRawIntBits(x));
2218 }
2219
2220 @ForceInline
2221 public final boolean weakCompareAndSetFloatAcquire(Object o, long offset,
2222 float expected,
2223 float x) {
2224 return weakCompareAndSetIntAcquire(o, offset,
2225 Float.floatToRawIntBits(expected),
2226 Float.floatToRawIntBits(x));
2227 }
2228
2229 @ForceInline
2230 public final boolean weakCompareAndSetFloatRelease(Object o, long offset,
2231 float expected,
2232 float x) {
2233 return weakCompareAndSetIntRelease(o, offset,
2234 Float.floatToRawIntBits(expected),
2235 Float.floatToRawIntBits(x));
2236 }
2237
2238 @ForceInline
2239 public final boolean weakCompareAndSetFloat(Object o, long offset,
2240 float expected,
2241 float x) {
2242 return weakCompareAndSetInt(o, offset,
2243 Float.floatToRawIntBits(expected),
2244 Float.floatToRawIntBits(x));
2245 }
2246
2247 /**
2248 * Atomically updates Java variable to {@code x} if it is currently
2249 * holding {@code expected}.
2250 *
2251 * <p>This operation has memory semantics of a {@code volatile} read
2252 * and write. Corresponds to C11 atomic_compare_exchange_strong.
2253 *
2254 * @return {@code true} if successful
2255 */
2256 @ForceInline
2257 public final boolean compareAndSetDouble(Object o, long offset,
2258 double expected,
2259 double x) {
2260 return compareAndSetLong(o, offset,
2261 Double.doubleToRawLongBits(expected),
2262 Double.doubleToRawLongBits(x));
2263 }
2264
2265 @ForceInline
2266 public final double compareAndExchangeDouble(Object o, long offset,
2267 double expected,
2268 double x) {
2269 long w = compareAndExchangeLong(o, offset,
2270 Double.doubleToRawLongBits(expected),
2271 Double.doubleToRawLongBits(x));
2272 return Double.longBitsToDouble(w);
2273 }
2274
2275 @ForceInline
2276 public final double compareAndExchangeDoubleAcquire(Object o, long offset,
2277 double expected,
2278 double x) {
2279 long w = compareAndExchangeLongAcquire(o, offset,
2280 Double.doubleToRawLongBits(expected),
2281 Double.doubleToRawLongBits(x));
2282 return Double.longBitsToDouble(w);
2283 }
2284
2285 @ForceInline
2286 public final double compareAndExchangeDoubleRelease(Object o, long offset,
2287 double expected,
2288 double x) {
2289 long w = compareAndExchangeLongRelease(o, offset,
2290 Double.doubleToRawLongBits(expected),
2291 Double.doubleToRawLongBits(x));
2292 return Double.longBitsToDouble(w);
2293 }
2294
2295 @ForceInline
2296 public final boolean weakCompareAndSetDoublePlain(Object o, long offset,
2297 double expected,
2298 double x) {
2299 return weakCompareAndSetLongPlain(o, offset,
2300 Double.doubleToRawLongBits(expected),
2301 Double.doubleToRawLongBits(x));
2302 }
2303
2304 @ForceInline
2305 public final boolean weakCompareAndSetDoubleAcquire(Object o, long offset,
2306 double expected,
2307 double x) {
2308 return weakCompareAndSetLongAcquire(o, offset,
2309 Double.doubleToRawLongBits(expected),
2310 Double.doubleToRawLongBits(x));
2311 }
2312
2313 @ForceInline
2314 public final boolean weakCompareAndSetDoubleRelease(Object o, long offset,
2315 double expected,
2316 double x) {
2317 return weakCompareAndSetLongRelease(o, offset,
2318 Double.doubleToRawLongBits(expected),
2319 Double.doubleToRawLongBits(x));
2320 }
2321
2322 @ForceInline
2323 public final boolean weakCompareAndSetDouble(Object o, long offset,
2324 double expected,
2325 double x) {
2326 return weakCompareAndSetLong(o, offset,
2327 Double.doubleToRawLongBits(expected),
2328 Double.doubleToRawLongBits(x));
2329 }
2330
2331 /**
2332 * Atomically updates Java variable to {@code x} if it is currently
2333 * holding {@code expected}.
2334 *
2335 * <p>This operation has memory semantics of a {@code volatile} read
2336 * and write. Corresponds to C11 atomic_compare_exchange_strong.
2337 *
2338 * @return {@code true} if successful
2339 */
2340 @HotSpotIntrinsicCandidate
2341 public final native boolean compareAndSetLong(Object o, long offset,
2342 long expected,
2343 long x);
2344
2345 @HotSpotIntrinsicCandidate
2346 public final native long compareAndExchangeLong(Object o, long offset,
2347 long expected,
2348 long x);
2349
2350 @HotSpotIntrinsicCandidate
2351 public final long compareAndExchangeLongAcquire(Object o, long offset,
2352 long expected,
2353 long x) {
2354 return compareAndExchangeLong(o, offset, expected, x);
2355 }
2356
2357 @HotSpotIntrinsicCandidate
2358 public final long compareAndExchangeLongRelease(Object o, long offset,
2359 long expected,
2360 long x) {
2361 return compareAndExchangeLong(o, offset, expected, x);
2362 }
2363
2364 @HotSpotIntrinsicCandidate
2365 public final boolean weakCompareAndSetLongPlain(Object o, long offset,
2366 long expected,
2367 long x) {
2368 return compareAndSetLong(o, offset, expected, x);
2369 }
2370
2371 @HotSpotIntrinsicCandidate
2372 public final boolean weakCompareAndSetLongAcquire(Object o, long offset,
2373 long expected,
2374 long x) {
2375 return compareAndSetLong(o, offset, expected, x);
2376 }
2377
2378 @HotSpotIntrinsicCandidate
2379 public final boolean weakCompareAndSetLongRelease(Object o, long offset,
2380 long expected,
2381 long x) {
2382 return compareAndSetLong(o, offset, expected, x);
2383 }
2384
2385 @HotSpotIntrinsicCandidate
2386 public final boolean weakCompareAndSetLong(Object o, long offset,
2387 long expected,
2388 long x) {
2389 return compareAndSetLong(o, offset, expected, x);
2390 }
2391
2392 /**
2393 * Fetches a reference value from a given Java variable, with volatile
2394 * load semantics. Otherwise identical to {@link #getReference(Object, long)}
2395 */
2396 @HotSpotIntrinsicCandidate
2397 public native Object getReferenceVolatile(Object o, long offset);
2398
2399 /**
2400 * Global lock for atomic and volatile strength access to any value of
2401 * an inline type. This is a temporary workaround until better localized
2402 * atomic access mechanisms are supported for inline types.
2403 */
2404 private static final Object valueLock = new Object();
2405
2406 public final <V> Object getValueVolatile(Object base, long offset, Class<?> valueType) {
2407 synchronized (valueLock) {
2408 return getValue(base, offset, valueType);
2409 }
2410 }
2411
2412 /**
2413 * Stores a reference value into a given Java variable, with
2414 * volatile store semantics. Otherwise identical to {@link #putReference(Object, long, Object)}
2415 */
2416 @HotSpotIntrinsicCandidate
2417 public native void putReferenceVolatile(Object o, long offset, Object x);
2418
2419 public final <V> void putValueVolatile(Object o, long offset, Class<?> valueType, V x) {
2420 synchronized (valueLock) {
2421 putValue(o, offset, valueType, x);
2422 }
2423 }
2424
2425 /** Volatile version of {@link #getInt(Object, long)} */
2426 @HotSpotIntrinsicCandidate
2427 public native int getIntVolatile(Object o, long offset);
2428
2429 /** Volatile version of {@link #putInt(Object, long, int)} */
2430 @HotSpotIntrinsicCandidate
2431 public native void putIntVolatile(Object o, long offset, int x);
2432
2433 /** Volatile version of {@link #getBoolean(Object, long)} */
2434 @HotSpotIntrinsicCandidate
2435 public native boolean getBooleanVolatile(Object o, long offset);
2436
2437 /** Volatile version of {@link #putBoolean(Object, long, boolean)} */
2438 @HotSpotIntrinsicCandidate
2439 public native void putBooleanVolatile(Object o, long offset, boolean x);
2440
2441 /** Volatile version of {@link #getByte(Object, long)} */
2442 @HotSpotIntrinsicCandidate
2443 public native byte getByteVolatile(Object o, long offset);
2444
2445 /** Volatile version of {@link #putByte(Object, long, byte)} */
2446 @HotSpotIntrinsicCandidate
2447 public native void putByteVolatile(Object o, long offset, byte x);
2448
2449 /** Volatile version of {@link #getShort(Object, long)} */
2450 @HotSpotIntrinsicCandidate
2451 public native short getShortVolatile(Object o, long offset);
2452
2453 /** Volatile version of {@link #putShort(Object, long, short)} */
2454 @HotSpotIntrinsicCandidate
2455 public native void putShortVolatile(Object o, long offset, short x);
2456
2457 /** Volatile version of {@link #getChar(Object, long)} */
2458 @HotSpotIntrinsicCandidate
2459 public native char getCharVolatile(Object o, long offset);
2460
2461 /** Volatile version of {@link #putChar(Object, long, char)} */
2462 @HotSpotIntrinsicCandidate
2463 public native void putCharVolatile(Object o, long offset, char x);
2464
2465 /** Volatile version of {@link #getLong(Object, long)} */
2466 @HotSpotIntrinsicCandidate
2467 public native long getLongVolatile(Object o, long offset);
2468
2469 /** Volatile version of {@link #putLong(Object, long, long)} */
2470 @HotSpotIntrinsicCandidate
2471 public native void putLongVolatile(Object o, long offset, long x);
2472
2473 /** Volatile version of {@link #getFloat(Object, long)} */
2474 @HotSpotIntrinsicCandidate
2475 public native float getFloatVolatile(Object o, long offset);
2476
2477 /** Volatile version of {@link #putFloat(Object, long, float)} */
2478 @HotSpotIntrinsicCandidate
2479 public native void putFloatVolatile(Object o, long offset, float x);
2480
2481 /** Volatile version of {@link #getDouble(Object, long)} */
2482 @HotSpotIntrinsicCandidate
2483 public native double getDoubleVolatile(Object o, long offset);
2484
2485 /** Volatile version of {@link #putDouble(Object, long, double)} */
2486 @HotSpotIntrinsicCandidate
2487 public native void putDoubleVolatile(Object o, long offset, double x);
2488
2489
2490
2491 /** Acquire version of {@link #getReferenceVolatile(Object, long)} */
2492 @HotSpotIntrinsicCandidate
2493 public final Object getReferenceAcquire(Object o, long offset) {
2494 return getReferenceVolatile(o, offset);
2495 }
2496
2497 public final <V> Object getValueAcquire(Object base, long offset, Class<?> valueType) {
2498 return getValueVolatile(base, offset, valueType);
2499 }
2500
2501 /** Acquire version of {@link #getBooleanVolatile(Object, long)} */
2502 @HotSpotIntrinsicCandidate
2503 public final boolean getBooleanAcquire(Object o, long offset) {
2504 return getBooleanVolatile(o, offset);
2505 }
2506
2507 /** Acquire version of {@link #getByteVolatile(Object, long)} */
2508 @HotSpotIntrinsicCandidate
2509 public final byte getByteAcquire(Object o, long offset) {
2510 return getByteVolatile(o, offset);
2511 }
2512
2513 /** Acquire version of {@link #getShortVolatile(Object, long)} */
2514 @HotSpotIntrinsicCandidate
2515 public final short getShortAcquire(Object o, long offset) {
2516 return getShortVolatile(o, offset);
2517 }
2518
2519 /** Acquire version of {@link #getCharVolatile(Object, long)} */
2520 @HotSpotIntrinsicCandidate
2521 public final char getCharAcquire(Object o, long offset) {
2522 return getCharVolatile(o, offset);
2523 }
2524
2525 /** Acquire version of {@link #getIntVolatile(Object, long)} */
2526 @HotSpotIntrinsicCandidate
2527 public final int getIntAcquire(Object o, long offset) {
2528 return getIntVolatile(o, offset);
2529 }
2530
2531 /** Acquire version of {@link #getFloatVolatile(Object, long)} */
2532 @HotSpotIntrinsicCandidate
2533 public final float getFloatAcquire(Object o, long offset) {
2534 return getFloatVolatile(o, offset);
2535 }
2536
2537 /** Acquire version of {@link #getLongVolatile(Object, long)} */
2538 @HotSpotIntrinsicCandidate
2539 public final long getLongAcquire(Object o, long offset) {
2540 return getLongVolatile(o, offset);
2541 }
2542
2543 /** Acquire version of {@link #getDoubleVolatile(Object, long)} */
2544 @HotSpotIntrinsicCandidate
2545 public final double getDoubleAcquire(Object o, long offset) {
2546 return getDoubleVolatile(o, offset);
2547 }
2548
2549 /*
2550 * Versions of {@link #putReferenceVolatile(Object, long, Object)}
2551 * that do not guarantee immediate visibility of the store to
2552 * other threads. This method is generally only useful if the
2553 * underlying field is a Java volatile (or if an array cell, one
2554 * that is otherwise only accessed using volatile accesses).
2555 *
2556 * Corresponds to C11 atomic_store_explicit(..., memory_order_release).
2557 */
2558
2559 /** Release version of {@link #putReferenceVolatile(Object, long, Object)} */
2560 @HotSpotIntrinsicCandidate
2561 public final void putReferenceRelease(Object o, long offset, Object x) {
2562 putReferenceVolatile(o, offset, x);
2563 }
2564
2565 public final <V> void putValueRelease(Object o, long offset, Class<?> valueType, V x) {
2566 putValueVolatile(o, offset, valueType, x);
2567 }
2568
2569 /** Release version of {@link #putBooleanVolatile(Object, long, boolean)} */
2570 @HotSpotIntrinsicCandidate
2571 public final void putBooleanRelease(Object o, long offset, boolean x) {
2572 putBooleanVolatile(o, offset, x);
2573 }
2574
2575 /** Release version of {@link #putByteVolatile(Object, long, byte)} */
2576 @HotSpotIntrinsicCandidate
2577 public final void putByteRelease(Object o, long offset, byte x) {
2578 putByteVolatile(o, offset, x);
2579 }
2580
2581 /** Release version of {@link #putShortVolatile(Object, long, short)} */
2582 @HotSpotIntrinsicCandidate
2583 public final void putShortRelease(Object o, long offset, short x) {
2584 putShortVolatile(o, offset, x);
2585 }
2586
2587 /** Release version of {@link #putCharVolatile(Object, long, char)} */
2588 @HotSpotIntrinsicCandidate
2589 public final void putCharRelease(Object o, long offset, char x) {
2590 putCharVolatile(o, offset, x);
2591 }
2592
2593 /** Release version of {@link #putIntVolatile(Object, long, int)} */
2594 @HotSpotIntrinsicCandidate
2595 public final void putIntRelease(Object o, long offset, int x) {
2596 putIntVolatile(o, offset, x);
2597 }
2598
2599 /** Release version of {@link #putFloatVolatile(Object, long, float)} */
2600 @HotSpotIntrinsicCandidate
2601 public final void putFloatRelease(Object o, long offset, float x) {
2602 putFloatVolatile(o, offset, x);
2603 }
2604
2605 /** Release version of {@link #putLongVolatile(Object, long, long)} */
2606 @HotSpotIntrinsicCandidate
2607 public final void putLongRelease(Object o, long offset, long x) {
2608 putLongVolatile(o, offset, x);
2609 }
2610
2611 /** Release version of {@link #putDoubleVolatile(Object, long, double)} */
2612 @HotSpotIntrinsicCandidate
2613 public final void putDoubleRelease(Object o, long offset, double x) {
2614 putDoubleVolatile(o, offset, x);
2615 }
2616
2617 // ------------------------------ Opaque --------------------------------------
2618
2619 /** Opaque version of {@link #getReferenceVolatile(Object, long)} */
2620 @HotSpotIntrinsicCandidate
2621 public final Object getReferenceOpaque(Object o, long offset) {
2622 return getReferenceVolatile(o, offset);
2623 }
2624
2625 public final <V> Object getValueOpaque(Object base, long offset, Class<?> valueType) {
2626 return getValueVolatile(base, offset, valueType);
2627 }
2628
2629 /** Opaque version of {@link #getBooleanVolatile(Object, long)} */
2630 @HotSpotIntrinsicCandidate
2631 public final boolean getBooleanOpaque(Object o, long offset) {
2632 return getBooleanVolatile(o, offset);
2633 }
2634
2635 /** Opaque version of {@link #getByteVolatile(Object, long)} */
2636 @HotSpotIntrinsicCandidate
2637 public final byte getByteOpaque(Object o, long offset) {
2638 return getByteVolatile(o, offset);
2639 }
2640
2641 /** Opaque version of {@link #getShortVolatile(Object, long)} */
2642 @HotSpotIntrinsicCandidate
2643 public final short getShortOpaque(Object o, long offset) {
2644 return getShortVolatile(o, offset);
2645 }
2646
2647 /** Opaque version of {@link #getCharVolatile(Object, long)} */
2648 @HotSpotIntrinsicCandidate
2649 public final char getCharOpaque(Object o, long offset) {
2650 return getCharVolatile(o, offset);
2651 }
2652
2653 /** Opaque version of {@link #getIntVolatile(Object, long)} */
2654 @HotSpotIntrinsicCandidate
2655 public final int getIntOpaque(Object o, long offset) {
2656 return getIntVolatile(o, offset);
2657 }
2658
2659 /** Opaque version of {@link #getFloatVolatile(Object, long)} */
2660 @HotSpotIntrinsicCandidate
2661 public final float getFloatOpaque(Object o, long offset) {
2662 return getFloatVolatile(o, offset);
2663 }
2664
2665 /** Opaque version of {@link #getLongVolatile(Object, long)} */
2666 @HotSpotIntrinsicCandidate
2667 public final long getLongOpaque(Object o, long offset) {
2668 return getLongVolatile(o, offset);
2669 }
2670
2671 /** Opaque version of {@link #getDoubleVolatile(Object, long)} */
2672 @HotSpotIntrinsicCandidate
2673 public final double getDoubleOpaque(Object o, long offset) {
2674 return getDoubleVolatile(o, offset);
2675 }
2676
2677 /** Opaque version of {@link #putReferenceVolatile(Object, long, Object)} */
2678 @HotSpotIntrinsicCandidate
2679 public final void putReferenceOpaque(Object o, long offset, Object x) {
2680 putReferenceVolatile(o, offset, x);
2681 }
2682
2683 public final <V> void putValueOpaque(Object o, long offset, Class<?> valueType, V x) {
2684 putValueVolatile(o, offset, valueType, x);
2685 }
2686
2687 /** Opaque version of {@link #putBooleanVolatile(Object, long, boolean)} */
2688 @HotSpotIntrinsicCandidate
2689 public final void putBooleanOpaque(Object o, long offset, boolean x) {
2690 putBooleanVolatile(o, offset, x);
2691 }
2692
2693 /** Opaque version of {@link #putByteVolatile(Object, long, byte)} */
2694 @HotSpotIntrinsicCandidate
2695 public final void putByteOpaque(Object o, long offset, byte x) {
2696 putByteVolatile(o, offset, x);
2697 }
2698
2699 /** Opaque version of {@link #putShortVolatile(Object, long, short)} */
2700 @HotSpotIntrinsicCandidate
2701 public final void putShortOpaque(Object o, long offset, short x) {
2702 putShortVolatile(o, offset, x);
2703 }
2704
2705 /** Opaque version of {@link #putCharVolatile(Object, long, char)} */
2706 @HotSpotIntrinsicCandidate
2707 public final void putCharOpaque(Object o, long offset, char x) {
2708 putCharVolatile(o, offset, x);
2709 }
2710
2711 /** Opaque version of {@link #putIntVolatile(Object, long, int)} */
2712 @HotSpotIntrinsicCandidate
2713 public final void putIntOpaque(Object o, long offset, int x) {
2714 putIntVolatile(o, offset, x);
2715 }
2716
2717 /** Opaque version of {@link #putFloatVolatile(Object, long, float)} */
2718 @HotSpotIntrinsicCandidate
2719 public final void putFloatOpaque(Object o, long offset, float x) {
2720 putFloatVolatile(o, offset, x);
2721 }
2722
2723 /** Opaque version of {@link #putLongVolatile(Object, long, long)} */
2724 @HotSpotIntrinsicCandidate
2725 public final void putLongOpaque(Object o, long offset, long x) {
2726 putLongVolatile(o, offset, x);
2727 }
2728
2729 /** Opaque version of {@link #putDoubleVolatile(Object, long, double)} */
2730 @HotSpotIntrinsicCandidate
2731 public final void putDoubleOpaque(Object o, long offset, double x) {
2732 putDoubleVolatile(o, offset, x);
2733 }
2734
2735 /**
2736 * Unblocks the given thread blocked on {@code park}, or, if it is
2737 * not blocked, causes the subsequent call to {@code park} not to
2738 * block. Note: this operation is "unsafe" solely because the
2739 * caller must somehow ensure that the thread has not been
2740 * destroyed. Nothing special is usually required to ensure this
2741 * when called from Java (in which there will ordinarily be a live
2742 * reference to the thread) but this is not nearly-automatically
2743 * so when calling from native code.
2744 *
2745 * @param thread the thread to unpark.
2746 */
2747 @HotSpotIntrinsicCandidate
2748 public native void unpark(Object thread);
2749
2750 /**
2751 * Blocks current thread, returning when a balancing
2752 * {@code unpark} occurs, or a balancing {@code unpark} has
2753 * already occurred, or the thread is interrupted, or, if not
2754 * absolute and time is not zero, the given time nanoseconds have
2755 * elapsed, or if absolute, the given deadline in milliseconds
2756 * since Epoch has passed, or spuriously (i.e., returning for no
2757 * "reason"). Note: This operation is in the Unsafe class only
2758 * because {@code unpark} is, so it would be strange to place it
2759 * elsewhere.
2760 */
2761 @HotSpotIntrinsicCandidate
2762 public native void park(boolean isAbsolute, long time);
2763
2764 /**
2765 * Gets the load average in the system run queue assigned
2766 * to the available processors averaged over various periods of time.
2767 * This method retrieves the given {@code nelem} samples and
2768 * assigns to the elements of the given {@code loadavg} array.
2769 * The system imposes a maximum of 3 samples, representing
2770 * averages over the last 1, 5, and 15 minutes, respectively.
2771 *
2772 * @param loadavg an array of double of size nelems
2773 * @param nelems the number of samples to be retrieved and
2774 * must be 1 to 3.
2775 *
2776 * @return the number of samples actually retrieved; or -1
2777 * if the load average is unobtainable.
2778 */
2779 public int getLoadAverage(double[] loadavg, int nelems) {
2780 if (nelems < 0 || nelems > 3 || nelems > loadavg.length) {
2781 throw new ArrayIndexOutOfBoundsException();
2782 }
2783
2784 return getLoadAverage0(loadavg, nelems);
2785 }
2786
2787 // The following contain CAS-based Java implementations used on
2788 // platforms not supporting native instructions
2789
2790 /**
2791 * Atomically adds the given value to the current value of a field
2792 * or array element within the given object {@code o}
2793 * at the given {@code offset}.
2794 *
2795 * @param o object/array to update the field/element in
2796 * @param offset field/element offset
2797 * @param delta the value to add
2798 * @return the previous value
2799 * @since 1.8
2800 */
2801 @HotSpotIntrinsicCandidate
2802 public final int getAndAddInt(Object o, long offset, int delta) {
2803 int v;
2804 do {
2805 v = getIntVolatile(o, offset);
2806 } while (!weakCompareAndSetInt(o, offset, v, v + delta));
2807 return v;
2808 }
2809
2810 @ForceInline
2811 public final int getAndAddIntRelease(Object o, long offset, int delta) {
2812 int v;
2813 do {
2814 v = getInt(o, offset);
2815 } while (!weakCompareAndSetIntRelease(o, offset, v, v + delta));
2816 return v;
2817 }
2818
2819 @ForceInline
2820 public final int getAndAddIntAcquire(Object o, long offset, int delta) {
2821 int v;
2822 do {
2823 v = getIntAcquire(o, offset);
2824 } while (!weakCompareAndSetIntAcquire(o, offset, v, v + delta));
2825 return v;
2826 }
2827
2828 /**
2829 * Atomically adds the given value to the current value of a field
2830 * or array element within the given object {@code o}
2831 * at the given {@code offset}.
2832 *
2833 * @param o object/array to update the field/element in
2834 * @param offset field/element offset
2835 * @param delta the value to add
2836 * @return the previous value
2837 * @since 1.8
2838 */
2839 @HotSpotIntrinsicCandidate
2840 public final long getAndAddLong(Object o, long offset, long delta) {
2841 long v;
2842 do {
2843 v = getLongVolatile(o, offset);
2844 } while (!weakCompareAndSetLong(o, offset, v, v + delta));
2845 return v;
2846 }
2847
2848 @ForceInline
2849 public final long getAndAddLongRelease(Object o, long offset, long delta) {
2850 long v;
2851 do {
2852 v = getLong(o, offset);
2853 } while (!weakCompareAndSetLongRelease(o, offset, v, v + delta));
2854 return v;
2855 }
2856
2857 @ForceInline
2858 public final long getAndAddLongAcquire(Object o, long offset, long delta) {
2859 long v;
2860 do {
2861 v = getLongAcquire(o, offset);
2862 } while (!weakCompareAndSetLongAcquire(o, offset, v, v + delta));
2863 return v;
2864 }
2865
2866 @HotSpotIntrinsicCandidate
2867 public final byte getAndAddByte(Object o, long offset, byte delta) {
2868 byte v;
2869 do {
2870 v = getByteVolatile(o, offset);
2871 } while (!weakCompareAndSetByte(o, offset, v, (byte) (v + delta)));
2872 return v;
2873 }
2874
2875 @ForceInline
2876 public final byte getAndAddByteRelease(Object o, long offset, byte delta) {
2877 byte v;
2878 do {
2879 v = getByte(o, offset);
2880 } while (!weakCompareAndSetByteRelease(o, offset, v, (byte) (v + delta)));
2881 return v;
2882 }
2883
2884 @ForceInline
2885 public final byte getAndAddByteAcquire(Object o, long offset, byte delta) {
2886 byte v;
2887 do {
2888 v = getByteAcquire(o, offset);
2889 } while (!weakCompareAndSetByteAcquire(o, offset, v, (byte) (v + delta)));
2890 return v;
2891 }
2892
2893 @HotSpotIntrinsicCandidate
2894 public final short getAndAddShort(Object o, long offset, short delta) {
2895 short v;
2896 do {
2897 v = getShortVolatile(o, offset);
2898 } while (!weakCompareAndSetShort(o, offset, v, (short) (v + delta)));
2899 return v;
2900 }
2901
2902 @ForceInline
2903 public final short getAndAddShortRelease(Object o, long offset, short delta) {
2904 short v;
2905 do {
2906 v = getShort(o, offset);
2907 } while (!weakCompareAndSetShortRelease(o, offset, v, (short) (v + delta)));
2908 return v;
2909 }
2910
2911 @ForceInline
2912 public final short getAndAddShortAcquire(Object o, long offset, short delta) {
2913 short v;
2914 do {
2915 v = getShortAcquire(o, offset);
2916 } while (!weakCompareAndSetShortAcquire(o, offset, v, (short) (v + delta)));
2917 return v;
2918 }
2919
2920 @ForceInline
2921 public final char getAndAddChar(Object o, long offset, char delta) {
2922 return (char) getAndAddShort(o, offset, (short) delta);
2923 }
2924
2925 @ForceInline
2926 public final char getAndAddCharRelease(Object o, long offset, char delta) {
2927 return (char) getAndAddShortRelease(o, offset, (short) delta);
2928 }
2929
2930 @ForceInline
2931 public final char getAndAddCharAcquire(Object o, long offset, char delta) {
2932 return (char) getAndAddShortAcquire(o, offset, (short) delta);
2933 }
2934
2935 @ForceInline
2936 public final float getAndAddFloat(Object o, long offset, float delta) {
2937 int expectedBits;
2938 float v;
2939 do {
2940 // Load and CAS with the raw bits to avoid issues with NaNs and
2941 // possible bit conversion from signaling NaNs to quiet NaNs that
2942 // may result in the loop not terminating.
2943 expectedBits = getIntVolatile(o, offset);
2944 v = Float.intBitsToFloat(expectedBits);
2945 } while (!weakCompareAndSetInt(o, offset,
2946 expectedBits, Float.floatToRawIntBits(v + delta)));
2947 return v;
2948 }
2949
2950 @ForceInline
2951 public final float getAndAddFloatRelease(Object o, long offset, float delta) {
2952 int expectedBits;
2953 float v;
2954 do {
2955 // Load and CAS with the raw bits to avoid issues with NaNs and
2956 // possible bit conversion from signaling NaNs to quiet NaNs that
2957 // may result in the loop not terminating.
2958 expectedBits = getInt(o, offset);
2959 v = Float.intBitsToFloat(expectedBits);
2960 } while (!weakCompareAndSetIntRelease(o, offset,
2961 expectedBits, Float.floatToRawIntBits(v + delta)));
2962 return v;
2963 }
2964
2965 @ForceInline
2966 public final float getAndAddFloatAcquire(Object o, long offset, float delta) {
2967 int expectedBits;
2968 float v;
2969 do {
2970 // Load and CAS with the raw bits to avoid issues with NaNs and
2971 // possible bit conversion from signaling NaNs to quiet NaNs that
2972 // may result in the loop not terminating.
2973 expectedBits = getIntAcquire(o, offset);
2974 v = Float.intBitsToFloat(expectedBits);
2975 } while (!weakCompareAndSetIntAcquire(o, offset,
2976 expectedBits, Float.floatToRawIntBits(v + delta)));
2977 return v;
2978 }
2979
2980 @ForceInline
2981 public final double getAndAddDouble(Object o, long offset, double delta) {
2982 long expectedBits;
2983 double v;
2984 do {
2985 // Load and CAS with the raw bits to avoid issues with NaNs and
2986 // possible bit conversion from signaling NaNs to quiet NaNs that
2987 // may result in the loop not terminating.
2988 expectedBits = getLongVolatile(o, offset);
2989 v = Double.longBitsToDouble(expectedBits);
2990 } while (!weakCompareAndSetLong(o, offset,
2991 expectedBits, Double.doubleToRawLongBits(v + delta)));
2992 return v;
2993 }
2994
2995 @ForceInline
2996 public final double getAndAddDoubleRelease(Object o, long offset, double delta) {
2997 long expectedBits;
2998 double v;
2999 do {
3000 // Load and CAS with the raw bits to avoid issues with NaNs and
3001 // possible bit conversion from signaling NaNs to quiet NaNs that
3002 // may result in the loop not terminating.
3003 expectedBits = getLong(o, offset);
3004 v = Double.longBitsToDouble(expectedBits);
3005 } while (!weakCompareAndSetLongRelease(o, offset,
3006 expectedBits, Double.doubleToRawLongBits(v + delta)));
3007 return v;
3008 }
3009
3010 @ForceInline
3011 public final double getAndAddDoubleAcquire(Object o, long offset, double delta) {
3012 long expectedBits;
3013 double v;
3014 do {
3015 // Load and CAS with the raw bits to avoid issues with NaNs and
3016 // possible bit conversion from signaling NaNs to quiet NaNs that
3017 // may result in the loop not terminating.
3018 expectedBits = getLongAcquire(o, offset);
3019 v = Double.longBitsToDouble(expectedBits);
3020 } while (!weakCompareAndSetLongAcquire(o, offset,
3021 expectedBits, Double.doubleToRawLongBits(v + delta)));
3022 return v;
3023 }
3024
3025 /**
3026 * Atomically exchanges the given value with the current value of
3027 * a field or array element within the given object {@code o}
3028 * at the given {@code offset}.
3029 *
3030 * @param o object/array to update the field/element in
3031 * @param offset field/element offset
3032 * @param newValue new value
3033 * @return the previous value
3034 * @since 1.8
3035 */
3036 @HotSpotIntrinsicCandidate
3037 public final int getAndSetInt(Object o, long offset, int newValue) {
3038 int v;
3039 do {
3040 v = getIntVolatile(o, offset);
3041 } while (!weakCompareAndSetInt(o, offset, v, newValue));
3042 return v;
3043 }
3044
3045 @ForceInline
3046 public final int getAndSetIntRelease(Object o, long offset, int newValue) {
3047 int v;
3048 do {
3049 v = getInt(o, offset);
3050 } while (!weakCompareAndSetIntRelease(o, offset, v, newValue));
3051 return v;
3052 }
3053
3054 @ForceInline
3055 public final int getAndSetIntAcquire(Object o, long offset, int newValue) {
3056 int v;
3057 do {
3058 v = getIntAcquire(o, offset);
3059 } while (!weakCompareAndSetIntAcquire(o, offset, v, newValue));
3060 return v;
3061 }
3062
3063 /**
3064 * Atomically exchanges the given value with the current value of
3065 * a field or array element within the given object {@code o}
3066 * at the given {@code offset}.
3067 *
3068 * @param o object/array to update the field/element in
3069 * @param offset field/element offset
3070 * @param newValue new value
3071 * @return the previous value
3072 * @since 1.8
3073 */
3074 @HotSpotIntrinsicCandidate
3075 public final long getAndSetLong(Object o, long offset, long newValue) {
3076 long v;
3077 do {
3078 v = getLongVolatile(o, offset);
3079 } while (!weakCompareAndSetLong(o, offset, v, newValue));
3080 return v;
3081 }
3082
3083 @ForceInline
3084 public final long getAndSetLongRelease(Object o, long offset, long newValue) {
3085 long v;
3086 do {
3087 v = getLong(o, offset);
3088 } while (!weakCompareAndSetLongRelease(o, offset, v, newValue));
3089 return v;
3090 }
3091
3092 @ForceInline
3093 public final long getAndSetLongAcquire(Object o, long offset, long newValue) {
3094 long v;
3095 do {
3096 v = getLongAcquire(o, offset);
3097 } while (!weakCompareAndSetLongAcquire(o, offset, v, newValue));
3098 return v;
3099 }
3100
3101 /**
3102 * Atomically exchanges the given reference value with the current
3103 * reference value of a field or array element within the given
3104 * object {@code o} at the given {@code offset}.
3105 *
3106 * @param o object/array to update the field/element in
3107 * @param offset field/element offset
3108 * @param newValue new value
3109 * @return the previous value
3110 * @since 1.8
3111 */
3112 @HotSpotIntrinsicCandidate
3113 public final Object getAndSetReference(Object o, long offset, Object newValue) {
3114 Object v;
3115 do {
3116 v = getReferenceVolatile(o, offset);
3117 } while (!weakCompareAndSetReference(o, offset, v, newValue));
3118 return v;
3119 }
3120
3121 @SuppressWarnings("unchecked")
3122 public final <V> Object getAndSetValue(Object o, long offset, Class<?> valueType, V newValue) {
3123 synchronized (valueLock) {
3124 Object oldValue = getValue(o, offset, valueType);
3125 putValue(o, offset, valueType, newValue);
3126 return oldValue;
3127 }
3128 }
3129
3130 @ForceInline
3131 public final Object getAndSetReferenceRelease(Object o, long offset, Object newValue) {
3132 Object v;
3133 do {
3134 v = getReference(o, offset);
3135 } while (!weakCompareAndSetReferenceRelease(o, offset, v, newValue));
3136 return v;
3137 }
3138
3139 @ForceInline
3140 public final <V> Object getAndSetValueRelease(Object o, long offset, Class<?> valueType, V newValue) {
3141 return getAndSetValue(o, offset, valueType, newValue);
3142 }
3143
3144 @ForceInline
3145 public final Object getAndSetReferenceAcquire(Object o, long offset, Object newValue) {
3146 Object v;
3147 do {
3148 v = getReferenceAcquire(o, offset);
3149 } while (!weakCompareAndSetReferenceAcquire(o, offset, v, newValue));
3150 return v;
3151 }
3152
3153 @ForceInline
3154 public final <V> Object getAndSetValueAcquire(Object o, long offset, Class<?> valueType, V newValue) {
3155 return getAndSetValue(o, offset, valueType, newValue);
3156 }
3157
3158 @HotSpotIntrinsicCandidate
3159 public final byte getAndSetByte(Object o, long offset, byte newValue) {
3160 byte v;
3161 do {
3162 v = getByteVolatile(o, offset);
3163 } while (!weakCompareAndSetByte(o, offset, v, newValue));
3164 return v;
3165 }
3166
3167 @ForceInline
3168 public final byte getAndSetByteRelease(Object o, long offset, byte newValue) {
3169 byte v;
3170 do {
3171 v = getByte(o, offset);
3172 } while (!weakCompareAndSetByteRelease(o, offset, v, newValue));
3173 return v;
3174 }
3175
3176 @ForceInline
3177 public final byte getAndSetByteAcquire(Object o, long offset, byte newValue) {
3178 byte v;
3179 do {
3180 v = getByteAcquire(o, offset);
3181 } while (!weakCompareAndSetByteAcquire(o, offset, v, newValue));
3182 return v;
3183 }
3184
3185 @ForceInline
3186 public final boolean getAndSetBoolean(Object o, long offset, boolean newValue) {
3187 return byte2bool(getAndSetByte(o, offset, bool2byte(newValue)));
3188 }
3189
3190 @ForceInline
3191 public final boolean getAndSetBooleanRelease(Object o, long offset, boolean newValue) {
3192 return byte2bool(getAndSetByteRelease(o, offset, bool2byte(newValue)));
3193 }
3194
3195 @ForceInline
3196 public final boolean getAndSetBooleanAcquire(Object o, long offset, boolean newValue) {
3197 return byte2bool(getAndSetByteAcquire(o, offset, bool2byte(newValue)));
3198 }
3199
3200 @HotSpotIntrinsicCandidate
3201 public final short getAndSetShort(Object o, long offset, short newValue) {
3202 short v;
3203 do {
3204 v = getShortVolatile(o, offset);
3205 } while (!weakCompareAndSetShort(o, offset, v, newValue));
3206 return v;
3207 }
3208
3209 @ForceInline
3210 public final short getAndSetShortRelease(Object o, long offset, short newValue) {
3211 short v;
3212 do {
3213 v = getShort(o, offset);
3214 } while (!weakCompareAndSetShortRelease(o, offset, v, newValue));
3215 return v;
3216 }
3217
3218 @ForceInline
3219 public final short getAndSetShortAcquire(Object o, long offset, short newValue) {
3220 short v;
3221 do {
3222 v = getShortAcquire(o, offset);
3223 } while (!weakCompareAndSetShortAcquire(o, offset, v, newValue));
3224 return v;
3225 }
3226
3227 @ForceInline
3228 public final char getAndSetChar(Object o, long offset, char newValue) {
3229 return s2c(getAndSetShort(o, offset, c2s(newValue)));
3230 }
3231
3232 @ForceInline
3233 public final char getAndSetCharRelease(Object o, long offset, char newValue) {
3234 return s2c(getAndSetShortRelease(o, offset, c2s(newValue)));
3235 }
3236
3237 @ForceInline
3238 public final char getAndSetCharAcquire(Object o, long offset, char newValue) {
3239 return s2c(getAndSetShortAcquire(o, offset, c2s(newValue)));
3240 }
3241
3242 @ForceInline
3243 public final float getAndSetFloat(Object o, long offset, float newValue) {
3244 int v = getAndSetInt(o, offset, Float.floatToRawIntBits(newValue));
3245 return Float.intBitsToFloat(v);
3246 }
3247
3248 @ForceInline
3249 public final float getAndSetFloatRelease(Object o, long offset, float newValue) {
3250 int v = getAndSetIntRelease(o, offset, Float.floatToRawIntBits(newValue));
3251 return Float.intBitsToFloat(v);
3252 }
3253
3254 @ForceInline
3255 public final float getAndSetFloatAcquire(Object o, long offset, float newValue) {
3256 int v = getAndSetIntAcquire(o, offset, Float.floatToRawIntBits(newValue));
3257 return Float.intBitsToFloat(v);
3258 }
3259
3260 @ForceInline
3261 public final double getAndSetDouble(Object o, long offset, double newValue) {
3262 long v = getAndSetLong(o, offset, Double.doubleToRawLongBits(newValue));
3263 return Double.longBitsToDouble(v);
3264 }
3265
3266 @ForceInline
3267 public final double getAndSetDoubleRelease(Object o, long offset, double newValue) {
3268 long v = getAndSetLongRelease(o, offset, Double.doubleToRawLongBits(newValue));
3269 return Double.longBitsToDouble(v);
3270 }
3271
3272 @ForceInline
3273 public final double getAndSetDoubleAcquire(Object o, long offset, double newValue) {
3274 long v = getAndSetLongAcquire(o, offset, Double.doubleToRawLongBits(newValue));
3275 return Double.longBitsToDouble(v);
3276 }
3277
3278
3279 // The following contain CAS-based Java implementations used on
3280 // platforms not supporting native instructions
3281
3282 @ForceInline
3283 public final boolean getAndBitwiseOrBoolean(Object o, long offset, boolean mask) {
3284 return byte2bool(getAndBitwiseOrByte(o, offset, bool2byte(mask)));
3285 }
3286
3287 @ForceInline
3288 public final boolean getAndBitwiseOrBooleanRelease(Object o, long offset, boolean mask) {
3289 return byte2bool(getAndBitwiseOrByteRelease(o, offset, bool2byte(mask)));
3290 }
3291
3292 @ForceInline
3293 public final boolean getAndBitwiseOrBooleanAcquire(Object o, long offset, boolean mask) {
3294 return byte2bool(getAndBitwiseOrByteAcquire(o, offset, bool2byte(mask)));
3295 }
3296
3297 @ForceInline
3298 public final boolean getAndBitwiseAndBoolean(Object o, long offset, boolean mask) {
3299 return byte2bool(getAndBitwiseAndByte(o, offset, bool2byte(mask)));
3300 }
3301
3302 @ForceInline
3303 public final boolean getAndBitwiseAndBooleanRelease(Object o, long offset, boolean mask) {
3304 return byte2bool(getAndBitwiseAndByteRelease(o, offset, bool2byte(mask)));
3305 }
3306
3307 @ForceInline
3308 public final boolean getAndBitwiseAndBooleanAcquire(Object o, long offset, boolean mask) {
3309 return byte2bool(getAndBitwiseAndByteAcquire(o, offset, bool2byte(mask)));
3310 }
3311
3312 @ForceInline
3313 public final boolean getAndBitwiseXorBoolean(Object o, long offset, boolean mask) {
3314 return byte2bool(getAndBitwiseXorByte(o, offset, bool2byte(mask)));
3315 }
3316
3317 @ForceInline
3318 public final boolean getAndBitwiseXorBooleanRelease(Object o, long offset, boolean mask) {
3319 return byte2bool(getAndBitwiseXorByteRelease(o, offset, bool2byte(mask)));
3320 }
3321
3322 @ForceInline
3323 public final boolean getAndBitwiseXorBooleanAcquire(Object o, long offset, boolean mask) {
3324 return byte2bool(getAndBitwiseXorByteAcquire(o, offset, bool2byte(mask)));
3325 }
3326
3327
3328 @ForceInline
3329 public final byte getAndBitwiseOrByte(Object o, long offset, byte mask) {
3330 byte current;
3331 do {
3332 current = getByteVolatile(o, offset);
3333 } while (!weakCompareAndSetByte(o, offset,
3334 current, (byte) (current | mask)));
3335 return current;
3336 }
3337
3338 @ForceInline
3339 public final byte getAndBitwiseOrByteRelease(Object o, long offset, byte mask) {
3340 byte current;
3341 do {
3342 current = getByte(o, offset);
3343 } while (!weakCompareAndSetByteRelease(o, offset,
3344 current, (byte) (current | mask)));
3345 return current;
3346 }
3347
3348 @ForceInline
3349 public final byte getAndBitwiseOrByteAcquire(Object o, long offset, byte mask) {
3350 byte current;
3351 do {
3352 // Plain read, the value is a hint, the acquire CAS does the work
3353 current = getByte(o, offset);
3354 } while (!weakCompareAndSetByteAcquire(o, offset,
3355 current, (byte) (current | mask)));
3356 return current;
3357 }
3358
3359 @ForceInline
3360 public final byte getAndBitwiseAndByte(Object o, long offset, byte mask) {
3361 byte current;
3362 do {
3363 current = getByteVolatile(o, offset);
3364 } while (!weakCompareAndSetByte(o, offset,
3365 current, (byte) (current & mask)));
3366 return current;
3367 }
3368
3369 @ForceInline
3370 public final byte getAndBitwiseAndByteRelease(Object o, long offset, byte mask) {
3371 byte current;
3372 do {
3373 current = getByte(o, offset);
3374 } while (!weakCompareAndSetByteRelease(o, offset,
3375 current, (byte) (current & mask)));
3376 return current;
3377 }
3378
3379 @ForceInline
3380 public final byte getAndBitwiseAndByteAcquire(Object o, long offset, byte mask) {
3381 byte current;
3382 do {
3383 // Plain read, the value is a hint, the acquire CAS does the work
3384 current = getByte(o, offset);
3385 } while (!weakCompareAndSetByteAcquire(o, offset,
3386 current, (byte) (current & mask)));
3387 return current;
3388 }
3389
3390 @ForceInline
3391 public final byte getAndBitwiseXorByte(Object o, long offset, byte mask) {
3392 byte current;
3393 do {
3394 current = getByteVolatile(o, offset);
3395 } while (!weakCompareAndSetByte(o, offset,
3396 current, (byte) (current ^ mask)));
3397 return current;
3398 }
3399
3400 @ForceInline
3401 public final byte getAndBitwiseXorByteRelease(Object o, long offset, byte mask) {
3402 byte current;
3403 do {
3404 current = getByte(o, offset);
3405 } while (!weakCompareAndSetByteRelease(o, offset,
3406 current, (byte) (current ^ mask)));
3407 return current;
3408 }
3409
3410 @ForceInline
3411 public final byte getAndBitwiseXorByteAcquire(Object o, long offset, byte mask) {
3412 byte current;
3413 do {
3414 // Plain read, the value is a hint, the acquire CAS does the work
3415 current = getByte(o, offset);
3416 } while (!weakCompareAndSetByteAcquire(o, offset,
3417 current, (byte) (current ^ mask)));
3418 return current;
3419 }
3420
3421
3422 @ForceInline
3423 public final char getAndBitwiseOrChar(Object o, long offset, char mask) {
3424 return s2c(getAndBitwiseOrShort(o, offset, c2s(mask)));
3425 }
3426
3427 @ForceInline
3428 public final char getAndBitwiseOrCharRelease(Object o, long offset, char mask) {
3429 return s2c(getAndBitwiseOrShortRelease(o, offset, c2s(mask)));
3430 }
3431
3432 @ForceInline
3433 public final char getAndBitwiseOrCharAcquire(Object o, long offset, char mask) {
3434 return s2c(getAndBitwiseOrShortAcquire(o, offset, c2s(mask)));
3435 }
3436
3437 @ForceInline
3438 public final char getAndBitwiseAndChar(Object o, long offset, char mask) {
3439 return s2c(getAndBitwiseAndShort(o, offset, c2s(mask)));
3440 }
3441
3442 @ForceInline
3443 public final char getAndBitwiseAndCharRelease(Object o, long offset, char mask) {
3444 return s2c(getAndBitwiseAndShortRelease(o, offset, c2s(mask)));
3445 }
3446
3447 @ForceInline
3448 public final char getAndBitwiseAndCharAcquire(Object o, long offset, char mask) {
3449 return s2c(getAndBitwiseAndShortAcquire(o, offset, c2s(mask)));
3450 }
3451
3452 @ForceInline
3453 public final char getAndBitwiseXorChar(Object o, long offset, char mask) {
3454 return s2c(getAndBitwiseXorShort(o, offset, c2s(mask)));
3455 }
3456
3457 @ForceInline
3458 public final char getAndBitwiseXorCharRelease(Object o, long offset, char mask) {
3459 return s2c(getAndBitwiseXorShortRelease(o, offset, c2s(mask)));
3460 }
3461
3462 @ForceInline
3463 public final char getAndBitwiseXorCharAcquire(Object o, long offset, char mask) {
3464 return s2c(getAndBitwiseXorShortAcquire(o, offset, c2s(mask)));
3465 }
3466
3467
3468 @ForceInline
3469 public final short getAndBitwiseOrShort(Object o, long offset, short mask) {
3470 short current;
3471 do {
3472 current = getShortVolatile(o, offset);
3473 } while (!weakCompareAndSetShort(o, offset,
3474 current, (short) (current | mask)));
3475 return current;
3476 }
3477
3478 @ForceInline
3479 public final short getAndBitwiseOrShortRelease(Object o, long offset, short mask) {
3480 short current;
3481 do {
3482 current = getShort(o, offset);
3483 } while (!weakCompareAndSetShortRelease(o, offset,
3484 current, (short) (current | mask)));
3485 return current;
3486 }
3487
3488 @ForceInline
3489 public final short getAndBitwiseOrShortAcquire(Object o, long offset, short mask) {
3490 short current;
3491 do {
3492 // Plain read, the value is a hint, the acquire CAS does the work
3493 current = getShort(o, offset);
3494 } while (!weakCompareAndSetShortAcquire(o, offset,
3495 current, (short) (current | mask)));
3496 return current;
3497 }
3498
3499 @ForceInline
3500 public final short getAndBitwiseAndShort(Object o, long offset, short mask) {
3501 short current;
3502 do {
3503 current = getShortVolatile(o, offset);
3504 } while (!weakCompareAndSetShort(o, offset,
3505 current, (short) (current & mask)));
3506 return current;
3507 }
3508
3509 @ForceInline
3510 public final short getAndBitwiseAndShortRelease(Object o, long offset, short mask) {
3511 short current;
3512 do {
3513 current = getShort(o, offset);
3514 } while (!weakCompareAndSetShortRelease(o, offset,
3515 current, (short) (current & mask)));
3516 return current;
3517 }
3518
3519 @ForceInline
3520 public final short getAndBitwiseAndShortAcquire(Object o, long offset, short mask) {
3521 short current;
3522 do {
3523 // Plain read, the value is a hint, the acquire CAS does the work
3524 current = getShort(o, offset);
3525 } while (!weakCompareAndSetShortAcquire(o, offset,
3526 current, (short) (current & mask)));
3527 return current;
3528 }
3529
3530 @ForceInline
3531 public final short getAndBitwiseXorShort(Object o, long offset, short mask) {
3532 short current;
3533 do {
3534 current = getShortVolatile(o, offset);
3535 } while (!weakCompareAndSetShort(o, offset,
3536 current, (short) (current ^ mask)));
3537 return current;
3538 }
3539
3540 @ForceInline
3541 public final short getAndBitwiseXorShortRelease(Object o, long offset, short mask) {
3542 short current;
3543 do {
3544 current = getShort(o, offset);
3545 } while (!weakCompareAndSetShortRelease(o, offset,
3546 current, (short) (current ^ mask)));
3547 return current;
3548 }
3549
3550 @ForceInline
3551 public final short getAndBitwiseXorShortAcquire(Object o, long offset, short mask) {
3552 short current;
3553 do {
3554 // Plain read, the value is a hint, the acquire CAS does the work
3555 current = getShort(o, offset);
3556 } while (!weakCompareAndSetShortAcquire(o, offset,
3557 current, (short) (current ^ mask)));
3558 return current;
3559 }
3560
3561
3562 @ForceInline
3563 public final int getAndBitwiseOrInt(Object o, long offset, int mask) {
3564 int current;
3565 do {
3566 current = getIntVolatile(o, offset);
3567 } while (!weakCompareAndSetInt(o, offset,
3568 current, current | mask));
3569 return current;
3570 }
3571
3572 @ForceInline
3573 public final int getAndBitwiseOrIntRelease(Object o, long offset, int mask) {
3574 int current;
3575 do {
3576 current = getInt(o, offset);
3577 } while (!weakCompareAndSetIntRelease(o, offset,
3578 current, current | mask));
3579 return current;
3580 }
3581
3582 @ForceInline
3583 public final int getAndBitwiseOrIntAcquire(Object o, long offset, int mask) {
3584 int current;
3585 do {
3586 // Plain read, the value is a hint, the acquire CAS does the work
3587 current = getInt(o, offset);
3588 } while (!weakCompareAndSetIntAcquire(o, offset,
3589 current, current | mask));
3590 return current;
3591 }
3592
3593 /**
3594 * Atomically replaces the current value of a field or array element within
3595 * the given object with the result of bitwise AND between the current value
3596 * and mask.
3597 *
3598 * @param o object/array to update the field/element in
3599 * @param offset field/element offset
3600 * @param mask the mask value
3601 * @return the previous value
3602 * @since 9
3603 */
3604 @ForceInline
3605 public final int getAndBitwiseAndInt(Object o, long offset, int mask) {
3606 int current;
3607 do {
3608 current = getIntVolatile(o, offset);
3609 } while (!weakCompareAndSetInt(o, offset,
3610 current, current & mask));
3611 return current;
3612 }
3613
3614 @ForceInline
3615 public final int getAndBitwiseAndIntRelease(Object o, long offset, int mask) {
3616 int current;
3617 do {
3618 current = getInt(o, offset);
3619 } while (!weakCompareAndSetIntRelease(o, offset,
3620 current, current & mask));
3621 return current;
3622 }
3623
3624 @ForceInline
3625 public final int getAndBitwiseAndIntAcquire(Object o, long offset, int mask) {
3626 int current;
3627 do {
3628 // Plain read, the value is a hint, the acquire CAS does the work
3629 current = getInt(o, offset);
3630 } while (!weakCompareAndSetIntAcquire(o, offset,
3631 current, current & mask));
3632 return current;
3633 }
3634
3635 @ForceInline
3636 public final int getAndBitwiseXorInt(Object o, long offset, int mask) {
3637 int current;
3638 do {
3639 current = getIntVolatile(o, offset);
3640 } while (!weakCompareAndSetInt(o, offset,
3641 current, current ^ mask));
3642 return current;
3643 }
3644
3645 @ForceInline
3646 public final int getAndBitwiseXorIntRelease(Object o, long offset, int mask) {
3647 int current;
3648 do {
3649 current = getInt(o, offset);
3650 } while (!weakCompareAndSetIntRelease(o, offset,
3651 current, current ^ mask));
3652 return current;
3653 }
3654
3655 @ForceInline
3656 public final int getAndBitwiseXorIntAcquire(Object o, long offset, int mask) {
3657 int current;
3658 do {
3659 // Plain read, the value is a hint, the acquire CAS does the work
3660 current = getInt(o, offset);
3661 } while (!weakCompareAndSetIntAcquire(o, offset,
3662 current, current ^ mask));
3663 return current;
3664 }
3665
3666
3667 @ForceInline
3668 public final long getAndBitwiseOrLong(Object o, long offset, long mask) {
3669 long current;
3670 do {
3671 current = getLongVolatile(o, offset);
3672 } while (!weakCompareAndSetLong(o, offset,
3673 current, current | mask));
3674 return current;
3675 }
3676
3677 @ForceInline
3678 public final long getAndBitwiseOrLongRelease(Object o, long offset, long mask) {
3679 long current;
3680 do {
3681 current = getLong(o, offset);
3682 } while (!weakCompareAndSetLongRelease(o, offset,
3683 current, current | mask));
3684 return current;
3685 }
3686
3687 @ForceInline
3688 public final long getAndBitwiseOrLongAcquire(Object o, long offset, long mask) {
3689 long current;
3690 do {
3691 // Plain read, the value is a hint, the acquire CAS does the work
3692 current = getLong(o, offset);
3693 } while (!weakCompareAndSetLongAcquire(o, offset,
3694 current, current | mask));
3695 return current;
3696 }
3697
3698 @ForceInline
3699 public final long getAndBitwiseAndLong(Object o, long offset, long mask) {
3700 long current;
3701 do {
3702 current = getLongVolatile(o, offset);
3703 } while (!weakCompareAndSetLong(o, offset,
3704 current, current & mask));
3705 return current;
3706 }
3707
3708 @ForceInline
3709 public final long getAndBitwiseAndLongRelease(Object o, long offset, long mask) {
3710 long current;
3711 do {
3712 current = getLong(o, offset);
3713 } while (!weakCompareAndSetLongRelease(o, offset,
3714 current, current & mask));
3715 return current;
3716 }
3717
3718 @ForceInline
3719 public final long getAndBitwiseAndLongAcquire(Object o, long offset, long mask) {
3720 long current;
3721 do {
3722 // Plain read, the value is a hint, the acquire CAS does the work
3723 current = getLong(o, offset);
3724 } while (!weakCompareAndSetLongAcquire(o, offset,
3725 current, current & mask));
3726 return current;
3727 }
3728
3729 @ForceInline
3730 public final long getAndBitwiseXorLong(Object o, long offset, long mask) {
3731 long current;
3732 do {
3733 current = getLongVolatile(o, offset);
3734 } while (!weakCompareAndSetLong(o, offset,
3735 current, current ^ mask));
3736 return current;
3737 }
3738
3739 @ForceInline
3740 public final long getAndBitwiseXorLongRelease(Object o, long offset, long mask) {
3741 long current;
3742 do {
3743 current = getLong(o, offset);
3744 } while (!weakCompareAndSetLongRelease(o, offset,
3745 current, current ^ mask));
3746 return current;
3747 }
3748
3749 @ForceInline
3750 public final long getAndBitwiseXorLongAcquire(Object o, long offset, long mask) {
3751 long current;
3752 do {
3753 // Plain read, the value is a hint, the acquire CAS does the work
3754 current = getLong(o, offset);
3755 } while (!weakCompareAndSetLongAcquire(o, offset,
3756 current, current ^ mask));
3757 return current;
3758 }
3759
3760
3761
3762 /**
3763 * Ensures that loads before the fence will not be reordered with loads and
3764 * stores after the fence; a "LoadLoad plus LoadStore barrier".
3765 *
3766 * Corresponds to C11 atomic_thread_fence(memory_order_acquire)
3767 * (an "acquire fence").
3768 *
3769 * A pure LoadLoad fence is not provided, since the addition of LoadStore
3770 * is almost always desired, and most current hardware instructions that
3771 * provide a LoadLoad barrier also provide a LoadStore barrier for free.
3772 * @since 1.8
3773 */
3774 @HotSpotIntrinsicCandidate
3775 public native void loadFence();
3776
3777 /**
3778 * Ensures that loads and stores before the fence will not be reordered with
3779 * stores after the fence; a "StoreStore plus LoadStore barrier".
3780 *
3781 * Corresponds to C11 atomic_thread_fence(memory_order_release)
3782 * (a "release fence").
3783 *
3784 * A pure StoreStore fence is not provided, since the addition of LoadStore
3785 * is almost always desired, and most current hardware instructions that
3786 * provide a StoreStore barrier also provide a LoadStore barrier for free.
3787 * @since 1.8
3788 */
3789 @HotSpotIntrinsicCandidate
3790 public native void storeFence();
3791
3792 /**
3793 * Ensures that loads and stores before the fence will not be reordered
3794 * with loads and stores after the fence. Implies the effects of both
3795 * loadFence() and storeFence(), and in addition, the effect of a StoreLoad
3796 * barrier.
3797 *
3798 * Corresponds to C11 atomic_thread_fence(memory_order_seq_cst).
3799 * @since 1.8
3800 */
3801 @HotSpotIntrinsicCandidate
3802 public native void fullFence();
3803
3804 /**
3805 * Ensures that loads before the fence will not be reordered with
3806 * loads after the fence.
3807 */
3808 public final void loadLoadFence() {
3809 loadFence();
3810 }
3811
3812 /**
3813 * Ensures that stores before the fence will not be reordered with
3814 * stores after the fence.
3815 */
3816 public final void storeStoreFence() {
3817 storeFence();
3818 }
3819
3820
3821 /**
3822 * Throws IllegalAccessError; for use by the VM for access control
3823 * error support.
3824 * @since 1.8
3825 */
3826 private static void throwIllegalAccessError() {
3827 throw new IllegalAccessError();
3828 }
3829
3830 /**
3831 * Throws NoSuchMethodError; for use by the VM for redefinition support.
3832 * @since 13
3833 */
3834 private static void throwNoSuchMethodError() {
3835 throw new NoSuchMethodError();
3836 }
3837
3838 /**
3839 * @return Returns true if the native byte ordering of this
3840 * platform is big-endian, false if it is little-endian.
3841 */
3842 public final boolean isBigEndian() { return BIG_ENDIAN; }
3843
3844 /**
3845 * @return Returns true if this platform is capable of performing
3846 * accesses at addresses which are not aligned for the type of the
3847 * primitive type being accessed, false otherwise.
3848 */
3849 public final boolean unalignedAccess() { return UNALIGNED_ACCESS; }
3850
3851 /**
3852 * Fetches a value at some byte offset into a given Java object.
3853 * More specifically, fetches a value within the given object
3854 * <code>o</code> at the given offset, or (if <code>o</code> is
3855 * null) from the memory address whose numerical value is the
3856 * given offset. <p>
3857 *
3858 * The specification of this method is the same as {@link
3859 * #getLong(Object, long)} except that the offset does not need to
3860 * have been obtained from {@link #objectFieldOffset} on the
3861 * {@link java.lang.reflect.Field} of some Java field. The value
3862 * in memory is raw data, and need not correspond to any Java
3863 * variable. Unless <code>o</code> is null, the value accessed
3864 * must be entirely within the allocated object. The endianness
3865 * of the value in memory is the endianness of the native platform.
3866 *
3867 * <p> The read will be atomic with respect to the largest power
3868 * of two that divides the GCD of the offset and the storage size.
3869 * For example, getLongUnaligned will make atomic reads of 2-, 4-,
3870 * or 8-byte storage units if the offset is zero mod 2, 4, or 8,
3871 * respectively. There are no other guarantees of atomicity.
3872 * <p>
3873 * 8-byte atomicity is only guaranteed on platforms on which
3874 * support atomic accesses to longs.
3875 *
3876 * @param o Java heap object in which the value resides, if any, else
3877 * null
3878 * @param offset The offset in bytes from the start of the object
3879 * @return the value fetched from the indicated object
3880 * @throws RuntimeException No defined exceptions are thrown, not even
3881 * {@link NullPointerException}
3882 * @since 9
3883 */
3884 @HotSpotIntrinsicCandidate
3885 public final long getLongUnaligned(Object o, long offset) {
3886 if ((offset & 7) == 0) {
3887 return getLong(o, offset);
3888 } else if ((offset & 3) == 0) {
3889 return makeLong(getInt(o, offset),
3890 getInt(o, offset + 4));
3891 } else if ((offset & 1) == 0) {
3892 return makeLong(getShort(o, offset),
3893 getShort(o, offset + 2),
3894 getShort(o, offset + 4),
3895 getShort(o, offset + 6));
3896 } else {
3897 return makeLong(getByte(o, offset),
3898 getByte(o, offset + 1),
3899 getByte(o, offset + 2),
3900 getByte(o, offset + 3),
3901 getByte(o, offset + 4),
3902 getByte(o, offset + 5),
3903 getByte(o, offset + 6),
3904 getByte(o, offset + 7));
3905 }
3906 }
3907 /**
3908 * As {@link #getLongUnaligned(Object, long)} but with an
3909 * additional argument which specifies the endianness of the value
3910 * as stored in memory.
3911 *
3912 * @param o Java heap object in which the variable resides
3913 * @param offset The offset in bytes from the start of the object
3914 * @param bigEndian The endianness of the value
3915 * @return the value fetched from the indicated object
3916 * @since 9
3917 */
3918 public final long getLongUnaligned(Object o, long offset, boolean bigEndian) {
3919 return convEndian(bigEndian, getLongUnaligned(o, offset));
3920 }
3921
3922 /** @see #getLongUnaligned(Object, long) */
3923 @HotSpotIntrinsicCandidate
3924 public final int getIntUnaligned(Object o, long offset) {
3925 if ((offset & 3) == 0) {
3926 return getInt(o, offset);
3927 } else if ((offset & 1) == 0) {
3928 return makeInt(getShort(o, offset),
3929 getShort(o, offset + 2));
3930 } else {
3931 return makeInt(getByte(o, offset),
3932 getByte(o, offset + 1),
3933 getByte(o, offset + 2),
3934 getByte(o, offset + 3));
3935 }
3936 }
3937 /** @see #getLongUnaligned(Object, long, boolean) */
3938 public final int getIntUnaligned(Object o, long offset, boolean bigEndian) {
3939 return convEndian(bigEndian, getIntUnaligned(o, offset));
3940 }
3941
3942 /** @see #getLongUnaligned(Object, long) */
3943 @HotSpotIntrinsicCandidate
3944 public final short getShortUnaligned(Object o, long offset) {
3945 if ((offset & 1) == 0) {
3946 return getShort(o, offset);
3947 } else {
3948 return makeShort(getByte(o, offset),
3949 getByte(o, offset + 1));
3950 }
3951 }
3952 /** @see #getLongUnaligned(Object, long, boolean) */
3953 public final short getShortUnaligned(Object o, long offset, boolean bigEndian) {
3954 return convEndian(bigEndian, getShortUnaligned(o, offset));
3955 }
3956
3957 /** @see #getLongUnaligned(Object, long) */
3958 @HotSpotIntrinsicCandidate
3959 public final char getCharUnaligned(Object o, long offset) {
3960 if ((offset & 1) == 0) {
3961 return getChar(o, offset);
3962 } else {
3963 return (char)makeShort(getByte(o, offset),
3964 getByte(o, offset + 1));
3965 }
3966 }
3967
3968 /** @see #getLongUnaligned(Object, long, boolean) */
3969 public final char getCharUnaligned(Object o, long offset, boolean bigEndian) {
3970 return convEndian(bigEndian, getCharUnaligned(o, offset));
3971 }
3972
3973 /**
3974 * Stores a value at some byte offset into a given Java object.
3975 * <p>
3976 * The specification of this method is the same as {@link
3977 * #getLong(Object, long)} except that the offset does not need to
3978 * have been obtained from {@link #objectFieldOffset} on the
3979 * {@link java.lang.reflect.Field} of some Java field. The value
3980 * in memory is raw data, and need not correspond to any Java
3981 * variable. The endianness of the value in memory is the
3982 * endianness of the native platform.
3983 * <p>
3984 * The write will be atomic with respect to the largest power of
3985 * two that divides the GCD of the offset and the storage size.
3986 * For example, putLongUnaligned will make atomic writes of 2-, 4-,
3987 * or 8-byte storage units if the offset is zero mod 2, 4, or 8,
3988 * respectively. There are no other guarantees of atomicity.
3989 * <p>
3990 * 8-byte atomicity is only guaranteed on platforms on which
3991 * support atomic accesses to longs.
3992 *
3993 * @param o Java heap object in which the value resides, if any, else
3994 * null
3995 * @param offset The offset in bytes from the start of the object
3996 * @param x the value to store
3997 * @throws RuntimeException No defined exceptions are thrown, not even
3998 * {@link NullPointerException}
3999 * @since 9
4000 */
4001 @HotSpotIntrinsicCandidate
4002 public final void putLongUnaligned(Object o, long offset, long x) {
4003 if ((offset & 7) == 0) {
4004 putLong(o, offset, x);
4005 } else if ((offset & 3) == 0) {
4006 putLongParts(o, offset,
4007 (int)(x >> 0),
4008 (int)(x >>> 32));
4009 } else if ((offset & 1) == 0) {
4010 putLongParts(o, offset,
4011 (short)(x >>> 0),
4012 (short)(x >>> 16),
4013 (short)(x >>> 32),
4014 (short)(x >>> 48));
4015 } else {
4016 putLongParts(o, offset,
4017 (byte)(x >>> 0),
4018 (byte)(x >>> 8),
4019 (byte)(x >>> 16),
4020 (byte)(x >>> 24),
4021 (byte)(x >>> 32),
4022 (byte)(x >>> 40),
4023 (byte)(x >>> 48),
4024 (byte)(x >>> 56));
4025 }
4026 }
4027
4028 /**
4029 * As {@link #putLongUnaligned(Object, long, long)} but with an additional
4030 * argument which specifies the endianness of the value as stored in memory.
4031 * @param o Java heap object in which the value resides
4032 * @param offset The offset in bytes from the start of the object
4033 * @param x the value to store
4034 * @param bigEndian The endianness of the value
4035 * @throws RuntimeException No defined exceptions are thrown, not even
4036 * {@link NullPointerException}
4037 * @since 9
4038 */
4039 public final void putLongUnaligned(Object o, long offset, long x, boolean bigEndian) {
4040 putLongUnaligned(o, offset, convEndian(bigEndian, x));
4041 }
4042
4043 /** @see #putLongUnaligned(Object, long, long) */
4044 @HotSpotIntrinsicCandidate
4045 public final void putIntUnaligned(Object o, long offset, int x) {
4046 if ((offset & 3) == 0) {
4047 putInt(o, offset, x);
4048 } else if ((offset & 1) == 0) {
4049 putIntParts(o, offset,
4050 (short)(x >> 0),
4051 (short)(x >>> 16));
4052 } else {
4053 putIntParts(o, offset,
4054 (byte)(x >>> 0),
4055 (byte)(x >>> 8),
4056 (byte)(x >>> 16),
4057 (byte)(x >>> 24));
4058 }
4059 }
4060 /** @see #putLongUnaligned(Object, long, long, boolean) */
4061 public final void putIntUnaligned(Object o, long offset, int x, boolean bigEndian) {
4062 putIntUnaligned(o, offset, convEndian(bigEndian, x));
4063 }
4064
4065 /** @see #putLongUnaligned(Object, long, long) */
4066 @HotSpotIntrinsicCandidate
4067 public final void putShortUnaligned(Object o, long offset, short x) {
4068 if ((offset & 1) == 0) {
4069 putShort(o, offset, x);
4070 } else {
4071 putShortParts(o, offset,
4072 (byte)(x >>> 0),
4073 (byte)(x >>> 8));
4074 }
4075 }
4076 /** @see #putLongUnaligned(Object, long, long, boolean) */
4077 public final void putShortUnaligned(Object o, long offset, short x, boolean bigEndian) {
4078 putShortUnaligned(o, offset, convEndian(bigEndian, x));
4079 }
4080
4081 /** @see #putLongUnaligned(Object, long, long) */
4082 @HotSpotIntrinsicCandidate
4083 public final void putCharUnaligned(Object o, long offset, char x) {
4084 putShortUnaligned(o, offset, (short)x);
4085 }
4086 /** @see #putLongUnaligned(Object, long, long, boolean) */
4087 public final void putCharUnaligned(Object o, long offset, char x, boolean bigEndian) {
4088 putCharUnaligned(o, offset, convEndian(bigEndian, x));
4089 }
4090
4091 private static int pickPos(int top, int pos) { return BIG_ENDIAN ? top - pos : pos; }
4092
4093 // These methods construct integers from bytes. The byte ordering
4094 // is the native endianness of this platform.
4095 private static long makeLong(byte i0, byte i1, byte i2, byte i3, byte i4, byte i5, byte i6, byte i7) {
4096 return ((toUnsignedLong(i0) << pickPos(56, 0))
4097 | (toUnsignedLong(i1) << pickPos(56, 8))
4098 | (toUnsignedLong(i2) << pickPos(56, 16))
4099 | (toUnsignedLong(i3) << pickPos(56, 24))
4100 | (toUnsignedLong(i4) << pickPos(56, 32))
4101 | (toUnsignedLong(i5) << pickPos(56, 40))
4102 | (toUnsignedLong(i6) << pickPos(56, 48))
4103 | (toUnsignedLong(i7) << pickPos(56, 56)));
4104 }
4105 private static long makeLong(short i0, short i1, short i2, short i3) {
4106 return ((toUnsignedLong(i0) << pickPos(48, 0))
4107 | (toUnsignedLong(i1) << pickPos(48, 16))
4108 | (toUnsignedLong(i2) << pickPos(48, 32))
4109 | (toUnsignedLong(i3) << pickPos(48, 48)));
4110 }
4111 private static long makeLong(int i0, int i1) {
4112 return (toUnsignedLong(i0) << pickPos(32, 0))
4113 | (toUnsignedLong(i1) << pickPos(32, 32));
4114 }
4115 private static int makeInt(short i0, short i1) {
4116 return (toUnsignedInt(i0) << pickPos(16, 0))
4117 | (toUnsignedInt(i1) << pickPos(16, 16));
4118 }
4119 private static int makeInt(byte i0, byte i1, byte i2, byte i3) {
4120 return ((toUnsignedInt(i0) << pickPos(24, 0))
4121 | (toUnsignedInt(i1) << pickPos(24, 8))
4122 | (toUnsignedInt(i2) << pickPos(24, 16))
4123 | (toUnsignedInt(i3) << pickPos(24, 24)));
4124 }
4125 private static short makeShort(byte i0, byte i1) {
4126 return (short)((toUnsignedInt(i0) << pickPos(8, 0))
4127 | (toUnsignedInt(i1) << pickPos(8, 8)));
4128 }
4129
4130 private static byte pick(byte le, byte be) { return BIG_ENDIAN ? be : le; }
4131 private static short pick(short le, short be) { return BIG_ENDIAN ? be : le; }
4132 private static int pick(int le, int be) { return BIG_ENDIAN ? be : le; }
4133
4134 // These methods write integers to memory from smaller parts
4135 // provided by their caller. The ordering in which these parts
4136 // are written is the native endianness of this platform.
4137 private void putLongParts(Object o, long offset, byte i0, byte i1, byte i2, byte i3, byte i4, byte i5, byte i6, byte i7) {
4138 putByte(o, offset + 0, pick(i0, i7));
4139 putByte(o, offset + 1, pick(i1, i6));
4140 putByte(o, offset + 2, pick(i2, i5));
4141 putByte(o, offset + 3, pick(i3, i4));
4142 putByte(o, offset + 4, pick(i4, i3));
4143 putByte(o, offset + 5, pick(i5, i2));
4144 putByte(o, offset + 6, pick(i6, i1));
4145 putByte(o, offset + 7, pick(i7, i0));
4146 }
4147 private void putLongParts(Object o, long offset, short i0, short i1, short i2, short i3) {
4148 putShort(o, offset + 0, pick(i0, i3));
4149 putShort(o, offset + 2, pick(i1, i2));
4150 putShort(o, offset + 4, pick(i2, i1));
4151 putShort(o, offset + 6, pick(i3, i0));
4152 }
4153 private void putLongParts(Object o, long offset, int i0, int i1) {
4154 putInt(o, offset + 0, pick(i0, i1));
4155 putInt(o, offset + 4, pick(i1, i0));
4156 }
4157 private void putIntParts(Object o, long offset, short i0, short i1) {
4158 putShort(o, offset + 0, pick(i0, i1));
4159 putShort(o, offset + 2, pick(i1, i0));
4160 }
4161 private void putIntParts(Object o, long offset, byte i0, byte i1, byte i2, byte i3) {
4162 putByte(o, offset + 0, pick(i0, i3));
4163 putByte(o, offset + 1, pick(i1, i2));
4164 putByte(o, offset + 2, pick(i2, i1));
4165 putByte(o, offset + 3, pick(i3, i0));
4166 }
4167 private void putShortParts(Object o, long offset, byte i0, byte i1) {
4168 putByte(o, offset + 0, pick(i0, i1));
4169 putByte(o, offset + 1, pick(i1, i0));
4170 }
4171
4172 // Zero-extend an integer
4173 private static int toUnsignedInt(byte n) { return n & 0xff; }
4174 private static int toUnsignedInt(short n) { return n & 0xffff; }
4175 private static long toUnsignedLong(byte n) { return n & 0xffl; }
4176 private static long toUnsignedLong(short n) { return n & 0xffffl; }
4177 private static long toUnsignedLong(int n) { return n & 0xffffffffl; }
4178
4179 // Maybe byte-reverse an integer
4180 private static char convEndian(boolean big, char n) { return big == BIG_ENDIAN ? n : Character.reverseBytes(n); }
4181 private static short convEndian(boolean big, short n) { return big == BIG_ENDIAN ? n : Short.reverseBytes(n) ; }
4182 private static int convEndian(boolean big, int n) { return big == BIG_ENDIAN ? n : Integer.reverseBytes(n) ; }
4183 private static long convEndian(boolean big, long n) { return big == BIG_ENDIAN ? n : Long.reverseBytes(n) ; }
4184
4185
4186
4187 private native long allocateMemory0(long bytes);
4188 private native long reallocateMemory0(long address, long bytes);
4189 private native void freeMemory0(long address);
4190 private native void setMemory0(Object o, long offset, long bytes, byte value);
4191 @HotSpotIntrinsicCandidate
4192 private native void copyMemory0(Object srcBase, long srcOffset, Object destBase, long destOffset, long bytes);
4193 private native void copySwapMemory0(Object srcBase, long srcOffset, Object destBase, long destOffset, long bytes, long elemSize);
4194 private native long objectFieldOffset0(Field f);
4195 private native long objectFieldOffset1(Class<?> c, String name);
4196 private native long staticFieldOffset0(Field f);
4197 private native Object staticFieldBase0(Field f);
4198 private native boolean shouldBeInitialized0(Class<?> c);
4199 private native void ensureClassInitialized0(Class<?> c);
4200 private native int arrayBaseOffset0(Class<?> arrayClass);
4201 private native int arrayIndexScale0(Class<?> arrayClass);
4202 private native long getObjectSize0(Object o);
4203 private native Class<?> defineAnonymousClass0(Class<?> hostClass, byte[] data, Object[] cpPatches);
4204 private native int getLoadAverage0(double[] loadavg, int nelems);
4205
4206
4207 /**
4208 * Invokes the given direct byte buffer's cleaner, if any.
4209 *
4210 * @param directBuffer a direct byte buffer
4211 * @throws NullPointerException if {@code directBuffer} is null
4212 * @throws IllegalArgumentException if {@code directBuffer} is non-direct,
4213 * or is a {@link java.nio.Buffer#slice slice}, or is a
4214 * {@link java.nio.Buffer#duplicate duplicate}
4215 */
4216 public void invokeCleaner(java.nio.ByteBuffer directBuffer) {
4217 if (!directBuffer.isDirect())
4218 throw new IllegalArgumentException("buffer is non-direct");
4219
4220 DirectBuffer db = (DirectBuffer) directBuffer;
4221 if (db.attachment() != null)
4222 throw new IllegalArgumentException("duplicate or slice");
4223
4224 Cleaner cleaner = db.cleaner();
4225 if (cleaner != null) {
4226 cleaner.clean();
4227 }
4228 }
4229
4230 // The following deprecated methods are used by JSR 166.
4231
4232 @Deprecated(since="12", forRemoval=true)
4233 public final Object getObject(Object o, long offset) {
4234 return getReference(o, offset);
4235 }
4236 @Deprecated(since="12", forRemoval=true)
4237 public final Object getObjectVolatile(Object o, long offset) {
4238 return getReferenceVolatile(o, offset);
4239 }
4240 @Deprecated(since="12", forRemoval=true)
4241 public final Object getObjectAcquire(Object o, long offset) {
4242 return getReferenceAcquire(o, offset);
4243 }
4244 @Deprecated(since="12", forRemoval=true)
4245 public final Object getObjectOpaque(Object o, long offset) {
4246 return getReferenceOpaque(o, offset);
4247 }
4248
4249
4250 @Deprecated(since="12", forRemoval=true)
4251 public final void putObject(Object o, long offset, Object x) {
4252 putReference(o, offset, x);
4253 }
4254 @Deprecated(since="12", forRemoval=true)
4255 public final void putObjectVolatile(Object o, long offset, Object x) {
4256 putReferenceVolatile(o, offset, x);
4257 }
4258 @Deprecated(since="12", forRemoval=true)
4259 public final void putObjectOpaque(Object o, long offset, Object x) {
4260 putReferenceOpaque(o, offset, x);
4261 }
4262 @Deprecated(since="12", forRemoval=true)
4263 public final void putObjectRelease(Object o, long offset, Object x) {
4264 putReferenceRelease(o, offset, x);
4265 }
4266
4267
4268 @Deprecated(since="12", forRemoval=true)
4269 public final Object getAndSetObject(Object o, long offset, Object newValue) {
4270 return getAndSetReference(o, offset, newValue);
4271 }
4272 @Deprecated(since="12", forRemoval=true)
4273 public final Object getAndSetObjectAcquire(Object o, long offset, Object newValue) {
4274 return getAndSetReferenceAcquire(o, offset, newValue);
4275 }
4276 @Deprecated(since="12", forRemoval=true)
4277 public final Object getAndSetObjectRelease(Object o, long offset, Object newValue) {
4278 return getAndSetReferenceRelease(o, offset, newValue);
4279 }
4280
4281
4282 @Deprecated(since="12", forRemoval=true)
4283 public final boolean compareAndSetObject(Object o, long offset, Object expected, Object x) {
4284 return compareAndSetReference(o, offset, expected, x);
4285 }
4286 @Deprecated(since="12", forRemoval=true)
4287 public final Object compareAndExchangeObject(Object o, long offset, Object expected, Object x) {
4288 return compareAndExchangeReference(o, offset, expected, x);
4289 }
4290 @Deprecated(since="12", forRemoval=true)
4291 public final Object compareAndExchangeObjectAcquire(Object o, long offset, Object expected, Object x) {
4292 return compareAndExchangeReferenceAcquire(o, offset, expected, x);
4293 }
4294 @Deprecated(since="12", forRemoval=true)
4295 public final Object compareAndExchangeObjectRelease(Object o, long offset, Object expected, Object x) {
4296 return compareAndExchangeReferenceRelease(o, offset, expected, x);
4297 }
4298
4299
4300 @Deprecated(since="12", forRemoval=true)
4301 public final boolean weakCompareAndSetObject(Object o, long offset, Object expected, Object x) {
4302 return weakCompareAndSetReference(o, offset, expected, x);
4303 }
4304 @Deprecated(since="12", forRemoval=true)
4305 public final boolean weakCompareAndSetObjectAcquire(Object o, long offset, Object expected, Object x) {
4306 return weakCompareAndSetReferenceAcquire(o, offset, expected, x);
4307 }
4308 @Deprecated(since="12", forRemoval=true)
4309 public final boolean weakCompareAndSetObjectPlain(Object o, long offset, Object expected, Object x) {
4310 return weakCompareAndSetReferencePlain(o, offset, expected, x);
4311 }
4312 @Deprecated(since="12", forRemoval=true)
4313 public final boolean weakCompareAndSetObjectRelease(Object o, long offset, Object expected, Object x) {
4314 return weakCompareAndSetReferenceRelease(o, offset, expected, x);
4315 }
4316 }