--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/src/jdk.unsupported/share/classes/sun/misc/Unsafe.java Tue Sep 12 19:03:39 2017 +0200
@@ -0,0 +1,1265 @@
+/*
+ * Copyright (c) 2000, 2017, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation. Oracle designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+package sun.misc;
+
+import jdk.internal.vm.annotation.ForceInline;
+import jdk.internal.misc.VM;
+import jdk.internal.ref.Cleaner;
+import jdk.internal.reflect.CallerSensitive;
+import jdk.internal.reflect.Reflection;
+import sun.nio.ch.DirectBuffer;
+
+import java.lang.reflect.Field;
+import java.security.ProtectionDomain;
+
+
+/**
+ * A collection of methods for performing low-level, unsafe operations.
+ * Although the class and all methods are public, use of this class is
+ * limited because only trusted code can obtain instances of it.
+ *
+ * <em>Note:</em> It is the resposibility of the caller to make sure
+ * arguments are checked before methods of this class are
+ * called. While some rudimentary checks are performed on the input,
+ * the checks are best effort and when performance is an overriding
+ * priority, as when methods of this class are optimized by the
+ * runtime compiler, some or all checks (if any) may be elided. Hence,
+ * the caller must not rely on the checks and corresponding
+ * exceptions!
+ *
+ * @author John R. Rose
+ * @see #getUnsafe
+ */
+
+public final class Unsafe {
+
+ static {
+ Reflection.registerMethodsToFilter(Unsafe.class, "getUnsafe");
+ }
+
+ private Unsafe() {}
+
+ private static final Unsafe theUnsafe = new Unsafe();
+ private static final jdk.internal.misc.Unsafe theInternalUnsafe = jdk.internal.misc.Unsafe.getUnsafe();
+
+ /**
+ * Provides the caller with the capability of performing unsafe
+ * operations.
+ *
+ * <p>The returned {@code Unsafe} object should be carefully guarded
+ * by the caller, since it can be used to read and write data at arbitrary
+ * memory addresses. It must never be passed to untrusted code.
+ *
+ * <p>Most methods in this class are very low-level, and correspond to a
+ * small number of hardware instructions (on typical machines). Compilers
+ * are encouraged to optimize these methods accordingly.
+ *
+ * <p>Here is a suggested idiom for using unsafe operations:
+ *
+ * <pre> {@code
+ * class MyTrustedClass {
+ * private static final Unsafe unsafe = Unsafe.getUnsafe();
+ * ...
+ * private long myCountAddress = ...;
+ * public int getCount() { return unsafe.getByte(myCountAddress); }
+ * }}</pre>
+ *
+ * (It may assist compilers to make the local variable {@code final}.)
+ *
+ * @throws SecurityException if the class loader of the caller
+ * class is not in the system domain in which all permissions
+ * are granted.
+ */
+ @CallerSensitive
+ public static Unsafe getUnsafe() {
+ Class<?> caller = Reflection.getCallerClass();
+ if (!VM.isSystemDomainLoader(caller.getClassLoader()))
+ throw new SecurityException("Unsafe");
+ return theUnsafe;
+ }
+
+ /// peek and poke operations
+ /// (compilers should optimize these to memory ops)
+
+ // These work on object fields in the Java heap.
+ // They will not work on elements of packed arrays.
+
+ /**
+ * Fetches a value from a given Java variable.
+ * More specifically, fetches a field or array element within the given
+ * object {@code o} at the given offset, or (if {@code o} is null)
+ * from the memory address whose numerical value is the given offset.
+ * <p>
+ * The results are undefined unless one of the following cases is true:
+ * <ul>
+ * <li>The offset was obtained from {@link #objectFieldOffset} on
+ * the {@link java.lang.reflect.Field} of some Java field and the object
+ * referred to by {@code o} is of a class compatible with that
+ * field's class.
+ *
+ * <li>The offset and object reference {@code o} (either null or
+ * non-null) were both obtained via {@link #staticFieldOffset}
+ * and {@link #staticFieldBase} (respectively) from the
+ * reflective {@link Field} representation of some Java field.
+ *
+ * <li>The object referred to by {@code o} is an array, and the offset
+ * is an integer of the form {@code B+N*S}, where {@code N} is
+ * a valid index into the array, and {@code B} and {@code S} are
+ * the values obtained by {@link #arrayBaseOffset} and {@link
+ * #arrayIndexScale} (respectively) from the array's class. The value
+ * referred to is the {@code N}<em>th</em> element of the array.
+ *
+ * </ul>
+ * <p>
+ * If one of the above cases is true, the call references a specific Java
+ * variable (field or array element). However, the results are undefined
+ * if that variable is not in fact of the type returned by this method.
+ * <p>
+ * This method refers to a variable by means of two parameters, and so
+ * it provides (in effect) a <em>double-register</em> addressing mode
+ * for Java variables. When the object reference is null, this method
+ * uses its offset as an absolute address. This is similar in operation
+ * to methods such as {@link #getInt(long)}, which provide (in effect) a
+ * <em>single-register</em> addressing mode for non-Java variables.
+ * However, because Java variables may have a different layout in memory
+ * from non-Java variables, programmers should not assume that these
+ * two addressing modes are ever equivalent. Also, programmers should
+ * remember that offsets from the double-register addressing mode cannot
+ * be portably confused with longs used in the single-register addressing
+ * mode.
+ *
+ * @param o Java heap object in which the variable resides, if any, else
+ * null
+ * @param offset indication of where the variable resides in a Java heap
+ * object, if any, else a memory address locating the variable
+ * statically
+ * @return the value fetched from the indicated Java variable
+ * @throws RuntimeException No defined exceptions are thrown, not even
+ * {@link NullPointerException}
+ */
+ @ForceInline
+ public int getInt(Object o, long offset) {
+ return theInternalUnsafe.getInt(o, offset);
+ }
+
+ /**
+ * Stores a value into a given Java variable.
+ * <p>
+ * The first two parameters are interpreted exactly as with
+ * {@link #getInt(Object, long)} to refer to a specific
+ * Java variable (field or array element). The given value
+ * is stored into that variable.
+ * <p>
+ * The variable must be of the same type as the method
+ * parameter {@code x}.
+ *
+ * @param o Java heap object in which the variable resides, if any, else
+ * null
+ * @param offset indication of where the variable resides in a Java heap
+ * object, if any, else a memory address locating the variable
+ * statically
+ * @param x the value to store into the indicated Java variable
+ * @throws RuntimeException No defined exceptions are thrown, not even
+ * {@link NullPointerException}
+ */
+ @ForceInline
+ public void putInt(Object o, long offset, int x) {
+ theInternalUnsafe.putInt(o, offset, x);
+ }
+
+ /**
+ * Fetches a reference value from a given Java variable.
+ * @see #getInt(Object, long)
+ */
+ @ForceInline
+ public Object getObject(Object o, long offset) {
+ return theInternalUnsafe.getObject(o, offset);
+ }
+
+ /**
+ * Stores a reference value into a given Java variable.
+ * <p>
+ * Unless the reference {@code x} being stored is either null
+ * or matches the field type, the results are undefined.
+ * If the reference {@code o} is non-null, card marks or
+ * other store barriers for that object (if the VM requires them)
+ * are updated.
+ * @see #putInt(Object, long, int)
+ */
+ @ForceInline
+ public void putObject(Object o, long offset, Object x) {
+ theInternalUnsafe.putObject(o, offset, x);
+ }
+
+ /** @see #getInt(Object, long) */
+ @ForceInline
+ public boolean getBoolean(Object o, long offset) {
+ return theInternalUnsafe.getBoolean(o, offset);
+ }
+
+ /** @see #putInt(Object, long, int) */
+ @ForceInline
+ public void putBoolean(Object o, long offset, boolean x) {
+ theInternalUnsafe.putBoolean(o, offset, x);
+ }
+
+ /** @see #getInt(Object, long) */
+ @ForceInline
+ public byte getByte(Object o, long offset) {
+ return theInternalUnsafe.getByte(o, offset);
+ }
+
+ /** @see #putInt(Object, long, int) */
+ @ForceInline
+ public void putByte(Object o, long offset, byte x) {
+ theInternalUnsafe.putByte(o, offset, x);
+ }
+
+ /** @see #getInt(Object, long) */
+ @ForceInline
+ public short getShort(Object o, long offset) {
+ return theInternalUnsafe.getShort(o, offset);
+ }
+
+ /** @see #putInt(Object, long, int) */
+ @ForceInline
+ public void putShort(Object o, long offset, short x) {
+ theInternalUnsafe.putShort(o, offset, x);
+ }
+
+ /** @see #getInt(Object, long) */
+ @ForceInline
+ public char getChar(Object o, long offset) {
+ return theInternalUnsafe.getChar(o, offset);
+ }
+
+ /** @see #putInt(Object, long, int) */
+ @ForceInline
+ public void putChar(Object o, long offset, char x) {
+ theInternalUnsafe.putChar(o, offset, x);
+ }
+
+ /** @see #getInt(Object, long) */
+ @ForceInline
+ public long getLong(Object o, long offset) {
+ return theInternalUnsafe.getLong(o, offset);
+ }
+
+ /** @see #putInt(Object, long, int) */
+ @ForceInline
+ public void putLong(Object o, long offset, long x) {
+ theInternalUnsafe.putLong(o, offset, x);
+ }
+
+ /** @see #getInt(Object, long) */
+ @ForceInline
+ public float getFloat(Object o, long offset) {
+ return theInternalUnsafe.getFloat(o, offset);
+ }
+
+ /** @see #putInt(Object, long, int) */
+ @ForceInline
+ public void putFloat(Object o, long offset, float x) {
+ theInternalUnsafe.putFloat(o, offset, x);
+ }
+
+ /** @see #getInt(Object, long) */
+ @ForceInline
+ public double getDouble(Object o, long offset) {
+ return theInternalUnsafe.getDouble(o, offset);
+ }
+
+ /** @see #putInt(Object, long, int) */
+ @ForceInline
+ public void putDouble(Object o, long offset, double x) {
+ theInternalUnsafe.putDouble(o, offset, x);
+ }
+
+ // These work on values in the C heap.
+
+ /**
+ * Fetches a value from a given memory address. If the address is zero, or
+ * does not point into a block obtained from {@link #allocateMemory}, the
+ * results are undefined.
+ *
+ * @see #allocateMemory
+ */
+ @ForceInline
+ public byte getByte(long address) {
+ return theInternalUnsafe.getByte(address);
+ }
+
+ /**
+ * Stores a value into a given memory address. If the address is zero, or
+ * does not point into a block obtained from {@link #allocateMemory}, the
+ * results are undefined.
+ *
+ * @see #getByte(long)
+ */
+ @ForceInline
+ public void putByte(long address, byte x) {
+ theInternalUnsafe.putByte(address, x);
+ }
+
+ /** @see #getByte(long) */
+ @ForceInline
+ public short getShort(long address) {
+ return theInternalUnsafe.getShort(address);
+ }
+
+ /** @see #putByte(long, byte) */
+ @ForceInline
+ public void putShort(long address, short x) {
+ theInternalUnsafe.putShort(address, x);
+ }
+
+ /** @see #getByte(long) */
+ @ForceInline
+ public char getChar(long address) {
+ return theInternalUnsafe.getChar(address);
+ }
+
+ /** @see #putByte(long, byte) */
+ @ForceInline
+ public void putChar(long address, char x) {
+ theInternalUnsafe.putChar(address, x);
+ }
+
+ /** @see #getByte(long) */
+ @ForceInline
+ public int getInt(long address) {
+ return theInternalUnsafe.getInt(address);
+ }
+
+ /** @see #putByte(long, byte) */
+ @ForceInline
+ public void putInt(long address, int x) {
+ theInternalUnsafe.putInt(address, x);
+ }
+
+ /** @see #getByte(long) */
+ @ForceInline
+ public long getLong(long address) {
+ return theInternalUnsafe.getLong(address);
+ }
+
+ /** @see #putByte(long, byte) */
+ @ForceInline
+ public void putLong(long address, long x) {
+ theInternalUnsafe.putLong(address, x);
+ }
+
+ /** @see #getByte(long) */
+ @ForceInline
+ public float getFloat(long address) {
+ return theInternalUnsafe.getFloat(address);
+ }
+
+ /** @see #putByte(long, byte) */
+ @ForceInline
+ public void putFloat(long address, float x) {
+ theInternalUnsafe.putFloat(address, x);
+ }
+
+ /** @see #getByte(long) */
+ @ForceInline
+ public double getDouble(long address) {
+ return theInternalUnsafe.getDouble(address);
+ }
+
+ /** @see #putByte(long, byte) */
+ @ForceInline
+ public void putDouble(long address, double x) {
+ theInternalUnsafe.putDouble(address, x);
+ }
+
+
+ /**
+ * Fetches a native pointer from a given memory address. If the address is
+ * zero, or does not point into a block obtained from {@link
+ * #allocateMemory}, the results are undefined.
+ *
+ * <p>If the native pointer is less than 64 bits wide, it is extended as
+ * an unsigned number to a Java long. The pointer may be indexed by any
+ * given byte offset, simply by adding that offset (as a simple integer) to
+ * the long representing the pointer. The number of bytes actually read
+ * from the target address may be determined by consulting {@link
+ * #addressSize}.
+ *
+ * @see #allocateMemory
+ */
+ @ForceInline
+ public long getAddress(long address) {
+ return theInternalUnsafe.getAddress(address);
+ }
+
+ /**
+ * Stores a native pointer into a given memory address. If the address is
+ * zero, or does not point into a block obtained from {@link
+ * #allocateMemory}, the results are undefined.
+ *
+ * <p>The number of bytes actually written at the target address may be
+ * determined by consulting {@link #addressSize}.
+ *
+ * @see #getAddress(long)
+ */
+ @ForceInline
+ public void putAddress(long address, long x) {
+ theInternalUnsafe.putAddress(address, x);
+ }
+
+
+ /// wrappers for malloc, realloc, free:
+
+ /**
+ * Allocates a new block of native memory, of the given size in bytes. The
+ * contents of the memory are uninitialized; they will generally be
+ * garbage. The resulting native pointer will never be zero, and will be
+ * aligned for all value types. Dispose of this memory by calling {@link
+ * #freeMemory}, or resize it with {@link #reallocateMemory}.
+ *
+ * <em>Note:</em> It is the resposibility of the caller to make
+ * sure arguments are checked before the methods are called. While
+ * some rudimentary checks are performed on the input, the checks
+ * are best effort and when performance is an overriding priority,
+ * as when methods of this class are optimized by the runtime
+ * compiler, some or all checks (if any) may be elided. Hence, the
+ * caller must not rely on the checks and corresponding
+ * exceptions!
+ *
+ * @throws RuntimeException if the size is negative or too large
+ * for the native size_t type
+ *
+ * @throws OutOfMemoryError if the allocation is refused by the system
+ *
+ * @see #getByte(long)
+ * @see #putByte(long, byte)
+ */
+ @ForceInline
+ public long allocateMemory(long bytes) {
+ return theInternalUnsafe.allocateMemory(bytes);
+ }
+
+ /**
+ * Resizes a new block of native memory, to the given size in bytes. The
+ * contents of the new block past the size of the old block are
+ * uninitialized; they will generally be garbage. The resulting native
+ * pointer will be zero if and only if the requested size is zero. The
+ * resulting native pointer will be aligned for all value types. Dispose
+ * of this memory by calling {@link #freeMemory}, or resize it with {@link
+ * #reallocateMemory}. The address passed to this method may be null, in
+ * which case an allocation will be performed.
+ *
+ * <em>Note:</em> It is the resposibility of the caller to make
+ * sure arguments are checked before the methods are called. While
+ * some rudimentary checks are performed on the input, the checks
+ * are best effort and when performance is an overriding priority,
+ * as when methods of this class are optimized by the runtime
+ * compiler, some or all checks (if any) may be elided. Hence, the
+ * caller must not rely on the checks and corresponding
+ * exceptions!
+ *
+ * @throws RuntimeException if the size is negative or too large
+ * for the native size_t type
+ *
+ * @throws OutOfMemoryError if the allocation is refused by the system
+ *
+ * @see #allocateMemory
+ */
+ @ForceInline
+ public long reallocateMemory(long address, long bytes) {
+ return theInternalUnsafe.reallocateMemory(address, bytes);
+ }
+
+ /**
+ * Sets all bytes in a given block of memory to a fixed value
+ * (usually zero).
+ *
+ * <p>This method determines a block's base address by means of two parameters,
+ * and so it provides (in effect) a <em>double-register</em> addressing mode,
+ * as discussed in {@link #getInt(Object,long)}. When the object reference is null,
+ * the offset supplies an absolute base address.
+ *
+ * <p>The stores are in coherent (atomic) units of a size determined
+ * by the address and length parameters. If the effective address and
+ * length are all even modulo 8, the stores take place in 'long' units.
+ * If the effective address and length are (resp.) even modulo 4 or 2,
+ * the stores take place in units of 'int' or 'short'.
+ *
+ * <em>Note:</em> It is the resposibility of the caller to make
+ * sure arguments are checked before the methods are called. While
+ * some rudimentary checks are performed on the input, the checks
+ * are best effort and when performance is an overriding priority,
+ * as when methods of this class are optimized by the runtime
+ * compiler, some or all checks (if any) may be elided. Hence, the
+ * caller must not rely on the checks and corresponding
+ * exceptions!
+ *
+ * @throws RuntimeException if any of the arguments is invalid
+ *
+ * @since 1.7
+ */
+ @ForceInline
+ public void setMemory(Object o, long offset, long bytes, byte value) {
+ theInternalUnsafe.setMemory(o, offset, bytes, value);
+ }
+
+ /**
+ * Sets all bytes in a given block of memory to a fixed value
+ * (usually zero). This provides a <em>single-register</em> addressing mode,
+ * as discussed in {@link #getInt(Object,long)}.
+ *
+ * <p>Equivalent to {@code setMemory(null, address, bytes, value)}.
+ */
+ @ForceInline
+ public void setMemory(long address, long bytes, byte value) {
+ theInternalUnsafe.setMemory(address, bytes, value);
+ }
+
+ /**
+ * Sets all bytes in a given block of memory to a copy of another
+ * block.
+ *
+ * <p>This method determines each block's base address by means of two parameters,
+ * and so it provides (in effect) a <em>double-register</em> addressing mode,
+ * as discussed in {@link #getInt(Object,long)}. When the object reference is null,
+ * the offset supplies an absolute base address.
+ *
+ * <p>The transfers are in coherent (atomic) units of a size determined
+ * by the address and length parameters. If the effective addresses and
+ * length are all even modulo 8, the transfer takes place in 'long' units.
+ * If the effective addresses and length are (resp.) even modulo 4 or 2,
+ * the transfer takes place in units of 'int' or 'short'.
+ *
+ * <em>Note:</em> It is the resposibility of the caller to make
+ * sure arguments are checked before the methods are called. While
+ * some rudimentary checks are performed on the input, the checks
+ * are best effort and when performance is an overriding priority,
+ * as when methods of this class are optimized by the runtime
+ * compiler, some or all checks (if any) may be elided. Hence, the
+ * caller must not rely on the checks and corresponding
+ * exceptions!
+ *
+ * @throws RuntimeException if any of the arguments is invalid
+ *
+ * @since 1.7
+ */
+ @ForceInline
+ public void copyMemory(Object srcBase, long srcOffset,
+ Object destBase, long destOffset,
+ long bytes) {
+ theInternalUnsafe.copyMemory(srcBase, srcOffset, destBase, destOffset, bytes);
+ }
+
+ /**
+ * Sets all bytes in a given block of memory to a copy of another
+ * block. This provides a <em>single-register</em> addressing mode,
+ * as discussed in {@link #getInt(Object,long)}.
+ *
+ * Equivalent to {@code copyMemory(null, srcAddress, null, destAddress, bytes)}.
+ */
+ @ForceInline
+ public void copyMemory(long srcAddress, long destAddress, long bytes) {
+ theInternalUnsafe.copyMemory(srcAddress, destAddress, bytes);
+ }
+
+ /**
+ * Disposes of a block of native memory, as obtained from {@link
+ * #allocateMemory} or {@link #reallocateMemory}. The address passed to
+ * this method may be null, in which case no action is taken.
+ *
+ * <em>Note:</em> It is the resposibility of the caller to make
+ * sure arguments are checked before the methods are called. While
+ * some rudimentary checks are performed on the input, the checks
+ * are best effort and when performance is an overriding priority,
+ * as when methods of this class are optimized by the runtime
+ * compiler, some or all checks (if any) may be elided. Hence, the
+ * caller must not rely on the checks and corresponding
+ * exceptions!
+ *
+ * @throws RuntimeException if any of the arguments is invalid
+ *
+ * @see #allocateMemory
+ */
+ @ForceInline
+ public void freeMemory(long address) {
+ theInternalUnsafe.freeMemory(address);
+ }
+
+ /// random queries
+
+ /**
+ * This constant differs from all results that will ever be returned from
+ * {@link #staticFieldOffset}, {@link #objectFieldOffset},
+ * or {@link #arrayBaseOffset}.
+ */
+ public static final int INVALID_FIELD_OFFSET = jdk.internal.misc.Unsafe.INVALID_FIELD_OFFSET;
+
+ /**
+ * Reports the location of a given field in the storage allocation of its
+ * class. Do not expect to perform any sort of arithmetic on this offset;
+ * it is just a cookie which is passed to the unsafe heap memory accessors.
+ *
+ * <p>Any given field will always have the same offset and base, and no
+ * two distinct fields of the same class will ever have the same offset
+ * and base.
+ *
+ * <p>As of 1.4.1, offsets for fields are represented as long values,
+ * although the Sun JVM does not use the most significant 32 bits.
+ * However, JVM implementations which store static fields at absolute
+ * addresses can use long offsets and null base pointers to express
+ * the field locations in a form usable by {@link #getInt(Object,long)}.
+ * Therefore, code which will be ported to such JVMs on 64-bit platforms
+ * must preserve all bits of static field offsets.
+ * @see #getInt(Object, long)
+ */
+ @ForceInline
+ public long objectFieldOffset(Field f) {
+ return theInternalUnsafe.objectFieldOffset(f);
+ }
+
+ /**
+ * Reports the location of a given static field, in conjunction with {@link
+ * #staticFieldBase}.
+ * <p>Do not expect to perform any sort of arithmetic on this offset;
+ * it is just a cookie which is passed to the unsafe heap memory accessors.
+ *
+ * <p>Any given field will always have the same offset, and no two distinct
+ * fields of the same class will ever have the same offset.
+ *
+ * <p>As of 1.4.1, offsets for fields are represented as long values,
+ * although the Sun JVM does not use the most significant 32 bits.
+ * It is hard to imagine a JVM technology which needs more than
+ * a few bits to encode an offset within a non-array object,
+ * However, for consistency with other methods in this class,
+ * this method reports its result as a long value.
+ * @see #getInt(Object, long)
+ */
+ @ForceInline
+ public long staticFieldOffset(Field f) {
+ return theInternalUnsafe.staticFieldOffset(f);
+ }
+
+ /**
+ * Reports the location of a given static field, in conjunction with {@link
+ * #staticFieldOffset}.
+ * <p>Fetch the base "Object", if any, with which static fields of the
+ * given class can be accessed via methods like {@link #getInt(Object,
+ * long)}. This value may be null. This value may refer to an object
+ * which is a "cookie", not guaranteed to be a real Object, and it should
+ * not be used in any way except as argument to the get and put routines in
+ * this class.
+ */
+ @ForceInline
+ public Object staticFieldBase(Field f) {
+ return theInternalUnsafe.staticFieldBase(f);
+ }
+
+ /**
+ * Detects if the given class may need to be initialized. This is often
+ * needed in conjunction with obtaining the static field base of a
+ * class.
+ * @return false only if a call to {@code ensureClassInitialized} would have no effect
+ */
+ @ForceInline
+ public boolean shouldBeInitialized(Class<?> c) {
+ return theInternalUnsafe.shouldBeInitialized(c);
+ }
+
+ /**
+ * Ensures the given class has been initialized. This is often
+ * needed in conjunction with obtaining the static field base of a
+ * class.
+ */
+ @ForceInline
+ public void ensureClassInitialized(Class<?> c) {
+ theInternalUnsafe.ensureClassInitialized(c);
+ }
+
+ /**
+ * Reports the offset of the first element in the storage allocation of a
+ * given array class. If {@link #arrayIndexScale} returns a non-zero value
+ * for the same class, you may use that scale factor, together with this
+ * base offset, to form new offsets to access elements of arrays of the
+ * given class.
+ *
+ * @see #getInt(Object, long)
+ * @see #putInt(Object, long, int)
+ */
+ @ForceInline
+ public int arrayBaseOffset(Class<?> arrayClass) {
+ return theInternalUnsafe.arrayBaseOffset(arrayClass);
+ }
+
+ /** The value of {@code arrayBaseOffset(boolean[].class)} */
+ public static final int ARRAY_BOOLEAN_BASE_OFFSET = jdk.internal.misc.Unsafe.ARRAY_BOOLEAN_BASE_OFFSET;
+
+ /** The value of {@code arrayBaseOffset(byte[].class)} */
+ public static final int ARRAY_BYTE_BASE_OFFSET = jdk.internal.misc.Unsafe.ARRAY_BYTE_BASE_OFFSET;
+
+ /** The value of {@code arrayBaseOffset(short[].class)} */
+ public static final int ARRAY_SHORT_BASE_OFFSET = jdk.internal.misc.Unsafe.ARRAY_SHORT_BASE_OFFSET;
+
+ /** The value of {@code arrayBaseOffset(char[].class)} */
+ public static final int ARRAY_CHAR_BASE_OFFSET = jdk.internal.misc.Unsafe.ARRAY_CHAR_BASE_OFFSET;
+
+ /** The value of {@code arrayBaseOffset(int[].class)} */
+ public static final int ARRAY_INT_BASE_OFFSET = jdk.internal.misc.Unsafe.ARRAY_INT_BASE_OFFSET;
+
+ /** The value of {@code arrayBaseOffset(long[].class)} */
+ public static final int ARRAY_LONG_BASE_OFFSET = jdk.internal.misc.Unsafe.ARRAY_LONG_BASE_OFFSET;
+
+ /** The value of {@code arrayBaseOffset(float[].class)} */
+ public static final int ARRAY_FLOAT_BASE_OFFSET = jdk.internal.misc.Unsafe.ARRAY_FLOAT_BASE_OFFSET;
+
+ /** The value of {@code arrayBaseOffset(double[].class)} */
+ public static final int ARRAY_DOUBLE_BASE_OFFSET = jdk.internal.misc.Unsafe.ARRAY_DOUBLE_BASE_OFFSET;
+
+ /** The value of {@code arrayBaseOffset(Object[].class)} */
+ public static final int ARRAY_OBJECT_BASE_OFFSET = jdk.internal.misc.Unsafe.ARRAY_OBJECT_BASE_OFFSET;
+
+ /**
+ * Reports the scale factor for addressing elements in the storage
+ * allocation of a given array class. However, arrays of "narrow" types
+ * will generally not work properly with accessors like {@link
+ * #getByte(Object, long)}, so the scale factor for such classes is reported
+ * as zero.
+ *
+ * @see #arrayBaseOffset
+ * @see #getInt(Object, long)
+ * @see #putInt(Object, long, int)
+ */
+ @ForceInline
+ public int arrayIndexScale(Class<?> arrayClass) {
+ return theInternalUnsafe.arrayIndexScale(arrayClass);
+ }
+
+ /** The value of {@code arrayIndexScale(boolean[].class)} */
+ public static final int ARRAY_BOOLEAN_INDEX_SCALE = jdk.internal.misc.Unsafe.ARRAY_BOOLEAN_INDEX_SCALE;
+
+ /** The value of {@code arrayIndexScale(byte[].class)} */
+ public static final int ARRAY_BYTE_INDEX_SCALE = jdk.internal.misc.Unsafe.ARRAY_BYTE_INDEX_SCALE;
+
+ /** The value of {@code arrayIndexScale(short[].class)} */
+ public static final int ARRAY_SHORT_INDEX_SCALE = jdk.internal.misc.Unsafe.ARRAY_SHORT_INDEX_SCALE;
+
+ /** The value of {@code arrayIndexScale(char[].class)} */
+ public static final int ARRAY_CHAR_INDEX_SCALE = jdk.internal.misc.Unsafe.ARRAY_CHAR_INDEX_SCALE;
+
+ /** The value of {@code arrayIndexScale(int[].class)} */
+ public static final int ARRAY_INT_INDEX_SCALE = jdk.internal.misc.Unsafe.ARRAY_INT_INDEX_SCALE;
+
+ /** The value of {@code arrayIndexScale(long[].class)} */
+ public static final int ARRAY_LONG_INDEX_SCALE = jdk.internal.misc.Unsafe.ARRAY_LONG_INDEX_SCALE;
+
+ /** The value of {@code arrayIndexScale(float[].class)} */
+ public static final int ARRAY_FLOAT_INDEX_SCALE = jdk.internal.misc.Unsafe.ARRAY_FLOAT_INDEX_SCALE;
+
+ /** The value of {@code arrayIndexScale(double[].class)} */
+ public static final int ARRAY_DOUBLE_INDEX_SCALE = jdk.internal.misc.Unsafe.ARRAY_DOUBLE_INDEX_SCALE;
+
+ /** The value of {@code arrayIndexScale(Object[].class)} */
+ public static final int ARRAY_OBJECT_INDEX_SCALE = jdk.internal.misc.Unsafe.ARRAY_OBJECT_INDEX_SCALE;
+
+ /**
+ * Reports the size in bytes of a native pointer, as stored via {@link
+ * #putAddress}. This value will be either 4 or 8. Note that the sizes of
+ * other primitive types (as stored in native memory blocks) is determined
+ * fully by their information content.
+ */
+ @ForceInline
+ public int addressSize() {
+ return theInternalUnsafe.addressSize();
+ }
+
+ /** The value of {@code addressSize()} */
+ public static final int ADDRESS_SIZE = theInternalUnsafe.addressSize();
+
+ /**
+ * Reports the size in bytes of a native memory page (whatever that is).
+ * This value will always be a power of two.
+ */
+ @ForceInline
+ public int pageSize() {
+ return theInternalUnsafe.pageSize();
+ }
+
+
+ /// random trusted operations from JNI:
+
+ /**
+ * Tells the VM to define a class, without security checks. By default, the
+ * class loader and protection domain come from the caller's class.
+ *
+ * @deprecated Use {@link java.lang.invoke.MethodHandles.Lookup#defineClass MethodHandles.Lookup#defineClass}
+ * to define a class to the same class loader and in the same runtime package
+ * and {@linkplain java.security.ProtectionDomain protection domain} of a
+ * given {@code Lookup}'s {@linkplain java.lang.invoke.MethodHandles.Lookup#lookupClass() lookup class}.
+ *
+ * @see java.lang.invoke.MethodHandles.Lookup#defineClass(byte[])
+ */
+ @Deprecated(since="9", forRemoval=true)
+ @ForceInline
+ public Class<?> defineClass(String name, byte[] b, int off, int len,
+ ClassLoader loader,
+ ProtectionDomain protectionDomain) {
+ return theInternalUnsafe.defineClass(name, b, off, len, loader, protectionDomain);
+ }
+
+ /**
+ * Defines a class but does not make it known to the class loader or system dictionary.
+ * <p>
+ * For each CP entry, the corresponding CP patch must either be null or have
+ * the a format that matches its tag:
+ * <ul>
+ * <li>Integer, Long, Float, Double: the corresponding wrapper object type from java.lang
+ * <li>Utf8: a string (must have suitable syntax if used as signature or name)
+ * <li>Class: any java.lang.Class object
+ * <li>String: any object (not just a java.lang.String)
+ * <li>InterfaceMethodRef: (NYI) a method handle to invoke on that call site's arguments
+ * </ul>
+ * @param hostClass context for linkage, access control, protection domain, and class loader
+ * @param data bytes of a class file
+ * @param cpPatches where non-null entries exist, they replace corresponding CP entries in data
+ */
+ @ForceInline
+ public Class<?> defineAnonymousClass(Class<?> hostClass, byte[] data, Object[] cpPatches) {
+ return theInternalUnsafe.defineAnonymousClass(hostClass, data, cpPatches);
+ }
+
+ /**
+ * Allocates an instance but does not run any constructor.
+ * Initializes the class if it has not yet been.
+ */
+ @ForceInline
+ public Object allocateInstance(Class<?> cls)
+ throws InstantiationException {
+ return theInternalUnsafe.allocateInstance(cls);
+ }
+
+ /** Throws the exception without telling the verifier. */
+ @ForceInline
+ public void throwException(Throwable ee) {
+ theInternalUnsafe.throwException(ee);
+ }
+
+ /**
+ * Atomically updates Java variable to {@code x} if it is currently
+ * holding {@code expected}.
+ *
+ * <p>This operation has memory semantics of a {@code volatile} read
+ * and write. Corresponds to C11 atomic_compare_exchange_strong.
+ *
+ * @return {@code true} if successful
+ */
+ @ForceInline
+ public final boolean compareAndSwapObject(Object o, long offset,
+ Object expected,
+ Object x) {
+ return theInternalUnsafe.compareAndSetObject(o, offset, expected, x);
+ }
+
+ /**
+ * Atomically updates Java variable to {@code x} if it is currently
+ * holding {@code expected}.
+ *
+ * <p>This operation has memory semantics of a {@code volatile} read
+ * and write. Corresponds to C11 atomic_compare_exchange_strong.
+ *
+ * @return {@code true} if successful
+ */
+ @ForceInline
+ public final boolean compareAndSwapInt(Object o, long offset,
+ int expected,
+ int x) {
+ return theInternalUnsafe.compareAndSetInt(o, offset, expected, x);
+ }
+
+ /**
+ * Atomically updates Java variable to {@code x} if it is currently
+ * holding {@code expected}.
+ *
+ * <p>This operation has memory semantics of a {@code volatile} read
+ * and write. Corresponds to C11 atomic_compare_exchange_strong.
+ *
+ * @return {@code true} if successful
+ */
+ @ForceInline
+ public final boolean compareAndSwapLong(Object o, long offset,
+ long expected,
+ long x) {
+ return theInternalUnsafe.compareAndSetLong(o, offset, expected, x);
+ }
+
+ /**
+ * Fetches a reference value from a given Java variable, with volatile
+ * load semantics. Otherwise identical to {@link #getObject(Object, long)}
+ */
+ @ForceInline
+ public Object getObjectVolatile(Object o, long offset) {
+ return theInternalUnsafe.getObjectVolatile(o, offset);
+ }
+
+ /**
+ * Stores a reference value into a given Java variable, with
+ * volatile store semantics. Otherwise identical to {@link #putObject(Object, long, Object)}
+ */
+ @ForceInline
+ public void putObjectVolatile(Object o, long offset, Object x) {
+ theInternalUnsafe.putObjectVolatile(o, offset, x);
+ }
+
+ /** Volatile version of {@link #getInt(Object, long)} */
+ @ForceInline
+ public int getIntVolatile(Object o, long offset) {
+ return theInternalUnsafe.getIntVolatile(o, offset);
+ }
+
+ /** Volatile version of {@link #putInt(Object, long, int)} */
+ @ForceInline
+ public void putIntVolatile(Object o, long offset, int x) {
+ theInternalUnsafe.putIntVolatile(o, offset, x);
+ }
+
+ /** Volatile version of {@link #getBoolean(Object, long)} */
+ @ForceInline
+ public boolean getBooleanVolatile(Object o, long offset) {
+ return theInternalUnsafe.getBooleanVolatile(o, offset);
+ }
+
+ /** Volatile version of {@link #putBoolean(Object, long, boolean)} */
+ @ForceInline
+ public void putBooleanVolatile(Object o, long offset, boolean x) {
+ theInternalUnsafe.putBooleanVolatile(o, offset, x);
+ }
+
+ /** Volatile version of {@link #getByte(Object, long)} */
+ @ForceInline
+ public byte getByteVolatile(Object o, long offset) {
+ return theInternalUnsafe.getByteVolatile(o, offset);
+ }
+
+ /** Volatile version of {@link #putByte(Object, long, byte)} */
+ @ForceInline
+ public void putByteVolatile(Object o, long offset, byte x) {
+ theInternalUnsafe.putByteVolatile(o, offset, x);
+ }
+
+ /** Volatile version of {@link #getShort(Object, long)} */
+ @ForceInline
+ public short getShortVolatile(Object o, long offset) {
+ return theInternalUnsafe.getShortVolatile(o, offset);
+ }
+
+ /** Volatile version of {@link #putShort(Object, long, short)} */
+ @ForceInline
+ public void putShortVolatile(Object o, long offset, short x) {
+ theInternalUnsafe.putShortVolatile(o, offset, x);
+ }
+
+ /** Volatile version of {@link #getChar(Object, long)} */
+ @ForceInline
+ public char getCharVolatile(Object o, long offset) {
+ return theInternalUnsafe.getCharVolatile(o, offset);
+ }
+
+ /** Volatile version of {@link #putChar(Object, long, char)} */
+ @ForceInline
+ public void putCharVolatile(Object o, long offset, char x) {
+ theInternalUnsafe.putCharVolatile(o, offset, x);
+ }
+
+ /** Volatile version of {@link #getLong(Object, long)} */
+ @ForceInline
+ public long getLongVolatile(Object o, long offset) {
+ return theInternalUnsafe.getLongVolatile(o, offset);
+ }
+
+ /** Volatile version of {@link #putLong(Object, long, long)} */
+ @ForceInline
+ public void putLongVolatile(Object o, long offset, long x) {
+ theInternalUnsafe.putLongVolatile(o, offset, x);
+ }
+
+ /** Volatile version of {@link #getFloat(Object, long)} */
+ @ForceInline
+ public float getFloatVolatile(Object o, long offset) {
+ return theInternalUnsafe.getFloatVolatile(o, offset);
+ }
+
+ /** Volatile version of {@link #putFloat(Object, long, float)} */
+ @ForceInline
+ public void putFloatVolatile(Object o, long offset, float x) {
+ theInternalUnsafe.putFloatVolatile(o, offset, x);
+ }
+
+ /** Volatile version of {@link #getDouble(Object, long)} */
+ @ForceInline
+ public double getDoubleVolatile(Object o, long offset) {
+ return theInternalUnsafe.getDoubleVolatile(o, offset);
+ }
+
+ /** Volatile version of {@link #putDouble(Object, long, double)} */
+ @ForceInline
+ public void putDoubleVolatile(Object o, long offset, double x) {
+ theInternalUnsafe.putDoubleVolatile(o, offset, x);
+ }
+
+ /**
+ * Version of {@link #putObjectVolatile(Object, long, Object)}
+ * that does not guarantee immediate visibility of the store to
+ * other threads. This method is generally only useful if the
+ * underlying field is a Java volatile (or if an array cell, one
+ * that is otherwise only accessed using volatile accesses).
+ *
+ * Corresponds to C11 atomic_store_explicit(..., memory_order_release).
+ */
+ @ForceInline
+ public void putOrderedObject(Object o, long offset, Object x) {
+ theInternalUnsafe.putObjectRelease(o, offset, x);
+ }
+
+ /** Ordered/Lazy version of {@link #putIntVolatile(Object, long, int)} */
+ @ForceInline
+ public void putOrderedInt(Object o, long offset, int x) {
+ theInternalUnsafe.putIntRelease(o, offset, x);
+ }
+
+ /** Ordered/Lazy version of {@link #putLongVolatile(Object, long, long)} */
+ @ForceInline
+ public void putOrderedLong(Object o, long offset, long x) {
+ theInternalUnsafe.putLongRelease(o, offset, x);
+ }
+
+ /**
+ * Unblocks the given thread blocked on {@code park}, or, if it is
+ * not blocked, causes the subsequent call to {@code park} not to
+ * block. Note: this operation is "unsafe" solely because the
+ * caller must somehow ensure that the thread has not been
+ * destroyed. Nothing special is usually required to ensure this
+ * when called from Java (in which there will ordinarily be a live
+ * reference to the thread) but this is not nearly-automatically
+ * so when calling from native code.
+ *
+ * @param thread the thread to unpark.
+ */
+ @ForceInline
+ public void unpark(Object thread) {
+ theInternalUnsafe.unpark(thread);
+ }
+
+ /**
+ * Blocks current thread, returning when a balancing
+ * {@code unpark} occurs, or a balancing {@code unpark} has
+ * already occurred, or the thread is interrupted, or, if not
+ * absolute and time is not zero, the given time nanoseconds have
+ * elapsed, or if absolute, the given deadline in milliseconds
+ * since Epoch has passed, or spuriously (i.e., returning for no
+ * "reason"). Note: This operation is in the Unsafe class only
+ * because {@code unpark} is, so it would be strange to place it
+ * elsewhere.
+ */
+ @ForceInline
+ public void park(boolean isAbsolute, long time) {
+ theInternalUnsafe.park(isAbsolute, time);
+ }
+
+ /**
+ * Gets the load average in the system run queue assigned
+ * to the available processors averaged over various periods of time.
+ * This method retrieves the given {@code nelem} samples and
+ * assigns to the elements of the given {@code loadavg} array.
+ * The system imposes a maximum of 3 samples, representing
+ * averages over the last 1, 5, and 15 minutes, respectively.
+ *
+ * @param loadavg an array of double of size nelems
+ * @param nelems the number of samples to be retrieved and
+ * must be 1 to 3.
+ *
+ * @return the number of samples actually retrieved; or -1
+ * if the load average is unobtainable.
+ */
+ @ForceInline
+ public int getLoadAverage(double[] loadavg, int nelems) {
+ return theInternalUnsafe.getLoadAverage(loadavg, nelems);
+ }
+
+ // The following contain CAS-based Java implementations used on
+ // platforms not supporting native instructions
+
+ /**
+ * Atomically adds the given value to the current value of a field
+ * or array element within the given object {@code o}
+ * at the given {@code offset}.
+ *
+ * @param o object/array to update the field/element in
+ * @param offset field/element offset
+ * @param delta the value to add
+ * @return the previous value
+ * @since 1.8
+ */
+ @ForceInline
+ public final int getAndAddInt(Object o, long offset, int delta) {
+ return theInternalUnsafe.getAndAddInt(o, offset, delta);
+ }
+
+ /**
+ * Atomically adds the given value to the current value of a field
+ * or array element within the given object {@code o}
+ * at the given {@code offset}.
+ *
+ * @param o object/array to update the field/element in
+ * @param offset field/element offset
+ * @param delta the value to add
+ * @return the previous value
+ * @since 1.8
+ */
+ @ForceInline
+ public final long getAndAddLong(Object o, long offset, long delta) {
+ return theInternalUnsafe.getAndAddLong(o, offset, delta);
+ }
+
+ /**
+ * Atomically exchanges the given value with the current value of
+ * a field or array element within the given object {@code o}
+ * at the given {@code offset}.
+ *
+ * @param o object/array to update the field/element in
+ * @param offset field/element offset
+ * @param newValue new value
+ * @return the previous value
+ * @since 1.8
+ */
+ @ForceInline
+ public final int getAndSetInt(Object o, long offset, int newValue) {
+ return theInternalUnsafe.getAndSetInt(o, offset, newValue);
+ }
+
+ /**
+ * Atomically exchanges the given value with the current value of
+ * a field or array element within the given object {@code o}
+ * at the given {@code offset}.
+ *
+ * @param o object/array to update the field/element in
+ * @param offset field/element offset
+ * @param newValue new value
+ * @return the previous value
+ * @since 1.8
+ */
+ @ForceInline
+ public final long getAndSetLong(Object o, long offset, long newValue) {
+ return theInternalUnsafe.getAndSetLong(o, offset, newValue);
+ }
+
+ /**
+ * Atomically exchanges the given reference value with the current
+ * reference value of a field or array element within the given
+ * object {@code o} at the given {@code offset}.
+ *
+ * @param o object/array to update the field/element in
+ * @param offset field/element offset
+ * @param newValue new value
+ * @return the previous value
+ * @since 1.8
+ */
+ @ForceInline
+ public final Object getAndSetObject(Object o, long offset, Object newValue) {
+ return theInternalUnsafe.getAndSetObject(o, offset, newValue);
+ }
+
+
+ /**
+ * Ensures that loads before the fence will not be reordered with loads and
+ * stores after the fence; a "LoadLoad plus LoadStore barrier".
+ *
+ * Corresponds to C11 atomic_thread_fence(memory_order_acquire)
+ * (an "acquire fence").
+ *
+ * A pure LoadLoad fence is not provided, since the addition of LoadStore
+ * is almost always desired, and most current hardware instructions that
+ * provide a LoadLoad barrier also provide a LoadStore barrier for free.
+ * @since 1.8
+ */
+ @ForceInline
+ public void loadFence() {
+ theInternalUnsafe.loadFence();
+ }
+
+ /**
+ * Ensures that loads and stores before the fence will not be reordered with
+ * stores after the fence; a "StoreStore plus LoadStore barrier".
+ *
+ * Corresponds to C11 atomic_thread_fence(memory_order_release)
+ * (a "release fence").
+ *
+ * A pure StoreStore fence is not provided, since the addition of LoadStore
+ * is almost always desired, and most current hardware instructions that
+ * provide a StoreStore barrier also provide a LoadStore barrier for free.
+ * @since 1.8
+ */
+ @ForceInline
+ public void storeFence() {
+ theInternalUnsafe.storeFence();
+ }
+
+ /**
+ * Ensures that loads and stores before the fence will not be reordered
+ * with loads and stores after the fence. Implies the effects of both
+ * loadFence() and storeFence(), and in addition, the effect of a StoreLoad
+ * barrier.
+ *
+ * Corresponds to C11 atomic_thread_fence(memory_order_seq_cst).
+ * @since 1.8
+ */
+ @ForceInline
+ public void fullFence() {
+ theInternalUnsafe.fullFence();
+ }
+
+ /**
+ * Invokes the given direct byte buffer's cleaner, if any.
+ *
+ * @param directBuffer a direct byte buffer
+ * @throws NullPointerException if {@code directBuffer} is null
+ * @throws IllegalArgumentException if {@code directBuffer} is non-direct,
+ * or is a {@link java.nio.Buffer#slice slice}, or is a
+ * {@link java.nio.Buffer#duplicate duplicate}
+ * @since 9
+ */
+ public void invokeCleaner(java.nio.ByteBuffer directBuffer) {
+ if (!directBuffer.isDirect())
+ throw new IllegalArgumentException("buffer is non-direct");
+
+ DirectBuffer db = (DirectBuffer)directBuffer;
+ if (db.attachment() != null)
+ throw new IllegalArgumentException("duplicate or slice");
+
+ Cleaner cleaner = db.cleaner();
+ if (cleaner != null) {
+ cleaner.clean();
+ }
+ }
+}