--- a/jdk/src/java.base/share/classes/sun/misc/Unsafe.java Sun Apr 10 08:41:00 2016 -0700
+++ /dev/null Thu Jan 01 00:00:00 1970 +0000
@@ -1,1270 +0,0 @@
-/*
- * Copyright (c) 2000, 2015, 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 sun.reflect.CallerSensitive;
-import sun.reflect.Reflection;
-
-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 {
- sun.reflect.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 a security manager exists and its
- * {@code checkPropertiesAccess} method doesn't allow
- * access to the system properties.
- */
- @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 read VM internal data.
-
- /**
- * Fetches an uncompressed reference value from a given native variable
- * ignoring the VM's compressed references mode.
- *
- * @param address a memory address locating the variable
- * @return the value fetched from the indicated native variable
- */
- @ForceInline
- public Object getUncompressedObject(long address) {
- return theInternalUnsafe.getUncompressedObject(address);
- }
-
- /**
- * Fetches the {@link java.lang.Class} Java mirror for the given native
- * metaspace {@code Klass} pointer.
- *
- * @param metaspaceKlass a native metaspace {@code Klass} pointer
- * @return the {@link java.lang.Class} Java mirror
- */
- @ForceInline
- public Class<?> getJavaMirror(long metaspaceKlass) {
- return theInternalUnsafe.getJavaMirror(metaspaceKlass);
- }
-
- /**
- * Fetches a native metaspace {@code Klass} pointer for the given Java
- * object.
- *
- * @param o Java heap object for which to fetch the class pointer
- * @return a native metaspace {@code Klass} pointer
- */
- @ForceInline
- public long getKlassPointer(Object o) {
- return theInternalUnsafe.getKlassPointer(o);
- }
-
- // 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.
- */
- @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.compareAndSwapObject(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.compareAndSwapInt(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.compareAndSwapLong(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.putOrderedObject(o, offset, x);
- }
-
- /** Ordered/Lazy version of {@link #putIntVolatile(Object, long, int)} */
- @ForceInline
- public void putOrderedInt(Object o, long offset, int x) {
- theInternalUnsafe.putOrderedInt(o, offset, x);
- }
-
- /** Ordered/Lazy version of {@link #putLongVolatile(Object, long, long)} */
- @ForceInline
- public void putOrderedLong(Object o, long offset, long x) {
- theInternalUnsafe.putOrderedLong(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();
- }
-}