org.graalvm.word.WordFactory Maven / Gradle / Ivy
/*
* Copyright (c) 2012, 2016, 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 org.graalvm.word;
import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;
public abstract class WordFactory {
/**
* Links a method to a canonical operation represented by an {@link FactoryOpcode} val.
*/
@Retention(RetentionPolicy.RUNTIME)
@Target(ElementType.METHOD)
protected @interface FactoryOperation {
FactoryOpcode opcode();
}
/**
* The canonical {@link FactoryOperation} represented by a method in a word type.
*/
protected enum FactoryOpcode {
ZERO,
FROM_UNSIGNED,
FROM_SIGNED,
}
protected interface BoxFactory {
T box(long val);
}
protected static BoxFactory boxFactory;
/**
* We allow subclassing, because only subclasses can access the protected inner classes that we
* use to mark the operations.
*/
protected WordFactory() {
}
/**
* The constant 0, i.e., the word with no bits set. There is no difference between a signed and
* unsigned zero.
*
* @return the constant 0.
*/
@FactoryOperation(opcode = FactoryOpcode.ZERO)
public static T zero() {
return boxFactory.box(0L);
}
/**
* The null pointer, i.e., the pointer with no bits set. There is no difference to a signed or
* unsigned {@link #zero}.
*
* @return the null pointer.
*/
@FactoryOperation(opcode = FactoryOpcode.ZERO)
public static T nullPointer() {
return boxFactory.box(0L);
}
/**
* Unsafe conversion from a Java long value to a Word. The parameter is treated as an unsigned
* 64-bit value (in contrast to the semantics of a Java long).
*
* @param val a 64 bit unsigned value
* @return the value cast to Word
*/
@FactoryOperation(opcode = FactoryOpcode.FROM_UNSIGNED)
public static T unsigned(long val) {
return boxFactory.box(val);
}
/**
* Unsafe conversion from a Java long value to a {@link PointerBase pointer}. The parameter is
* treated as an unsigned 64-bit value (in contrast to the semantics of a Java long).
*
* @param val a 64 bit unsigned value
* @return the value cast to PointerBase
*/
@FactoryOperation(opcode = FactoryOpcode.FROM_UNSIGNED)
public static T pointer(long val) {
return boxFactory.box(val);
}
/**
* Unsafe conversion from a Java int value to a Word. The parameter is treated as an unsigned
* 32-bit value (in contrast to the semantics of a Java int).
*
* @param val a 32 bit unsigned value
* @return the value cast to Word
*/
@FactoryOperation(opcode = FactoryOpcode.FROM_UNSIGNED)
public static T unsigned(int val) {
return boxFactory.box(val & 0xffffffffL);
}
/**
* Unsafe conversion from a Java long value to a Word. The parameter is treated as a signed
* 64-bit value (unchanged semantics of a Java long).
*
* @param val a 64 bit signed value
* @return the value cast to Word
*/
@FactoryOperation(opcode = FactoryOpcode.FROM_SIGNED)
public static T signed(long val) {
return boxFactory.box(val);
}
/**
* Unsafe conversion from a Java int value to a Word. The parameter is treated as a signed
* 32-bit value (unchanged semantics of a Java int).
*
* @param val a 32 bit signed value
* @return the value cast to Word
*/
@FactoryOperation(opcode = FactoryOpcode.FROM_SIGNED)
public static T signed(int val) {
return boxFactory.box(val);
}
}