src/jdk.internal.vm.compiler/share/classes/jdk.internal.vm.compiler.word/src/jdk/internal/vm/compiler/word/WordFactory.java

/*
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 * 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.
 *
 * 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
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package jdk.internal.vm.compiler.word;

import jdk.internal.vm.compiler.word.impl.WordBoxFactory;
import jdk.internal.vm.compiler.word.impl.WordFactoryOpcode;
import jdk.internal.vm.compiler.word.impl.WordFactoryOperation;

/**
 * Provides factory method to create machine-word-sized values.
 *
 * @since 1.0
 */
public final class WordFactory {

    private 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.
     *
     * @since 1.0
     */
    @WordFactoryOperation(opcode = WordFactoryOpcode.ZERO)
    public static <T extends WordBase> T zero() {
        return WordBoxFactory.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.
     *
     * @since 1.0
     */
    @WordFactoryOperation(opcode = WordFactoryOpcode.ZERO)
    public static <T extends PointerBase> T nullPointer() {
        return WordBoxFactory.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
     *
     * @since 1.0
     */
    @WordFactoryOperation(opcode = WordFactoryOpcode.FROM_UNSIGNED)
    public static <T extends UnsignedWord> T unsigned(long val) {
        return WordBoxFactory.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
     *
     * @since 1.0
     */
    @WordFactoryOperation(opcode = WordFactoryOpcode.FROM_UNSIGNED)
    public static <T extends PointerBase> T pointer(long val) {
        return WordBoxFactory.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
     *
     * @since 1.0
     */
    @WordFactoryOperation(opcode = WordFactoryOpcode.FROM_UNSIGNED)
    public static <T extends UnsignedWord> T unsigned(int val) {
        return WordBoxFactory.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
     *
     * @since 1.0
     */
    @WordFactoryOperation(opcode = WordFactoryOpcode.FROM_SIGNED)
    public static <T extends SignedWord> T signed(long val) {
        return WordBoxFactory.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
     *
     * @since 1.0
     */
    @WordFactoryOperation(opcode = WordFactoryOpcode.FROM_SIGNED)
    public static <T extends SignedWord> T signed(int val) {
        return WordBoxFactory.box(val);
    }
}