/*

 * Copyright (c) 2013, 2019, 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.

 *

 * 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.compiler.hotspot.stubs;

import static org.graalvm.compiler.replacements.nodes.CStringConstant.cstring;

import java.lang.reflect.Method;

import java.lang.reflect.Modifier;

import java.util.Arrays;

import java.util.List;

import org.graalvm.compiler.api.replacements.Fold;

import org.graalvm.compiler.api.replacements.Fold.InjectedParameter;

import org.graalvm.compiler.core.common.spi.ForeignCallDescriptor;

import org.graalvm.compiler.graph.Node.ConstantNodeParameter;

import org.graalvm.compiler.graph.Node.NodeIntrinsic;

import org.graalvm.compiler.hotspot.GraalHotSpotVMConfig;

import org.graalvm.compiler.hotspot.nodes.StubForeignCallNode;

import org.graalvm.compiler.hotspot.nodes.VMErrorNode;

import org.graalvm.compiler.hotspot.replacements.Log;

import org.graalvm.compiler.word.Word;

import jdk.internal.vm.compiler.word.WordFactory;

//JaCoCo Exclude

/**

 * A collection of methods used in {@link Stub}s.

 */

public class StubUtil {

    public static final ForeignCallDescriptor VM_MESSAGE_C = newDescriptor(StubUtil.class, "vmMessageC", void.class, boolean.class, Word.class, long.class, long.class, long.class);

    public static ForeignCallDescriptor newDescriptor(Class<?> stubClass, String name, Class<?> resultType, Class<?>... argumentTypes) {

        ForeignCallDescriptor d = new ForeignCallDescriptor(name, resultType, argumentTypes);

        assert descriptorFor(stubClass, name).equals(d) : descriptorFor(stubClass, name) + " != " + d;

        return d;

    }

    /**

     * Looks for a {@link StubForeignCallNode} node intrinsic named {@code name} in

     * {@code stubClass} and returns a {@link ForeignCallDescriptor} based on its signature and the

     * value of {@code hasSideEffect}.

     */

    private static ForeignCallDescriptor descriptorFor(Class<?> stubClass, String name) {

        Method found = null;

        for (Method method : stubClass.getDeclaredMethods()) {

            if (Modifier.isStatic(method.getModifiers()) && method.getAnnotation(NodeIntrinsic.class) != null && method.getName().equals(name)) {

                if (method.getAnnotation(NodeIntrinsic.class).value().equals(StubForeignCallNode.class)) {

                    assert found == null : "found more than one foreign call named " + name + " in " + stubClass;

                    assert method.getParameterTypes().length != 0 && method.getParameterTypes()[0] == ForeignCallDescriptor.class : "first parameter of foreign call '" + name + "' in " + stubClass +

                                    " must be of type " + ForeignCallDescriptor.class.getSimpleName();

                    found = method;

                }

            }

        }

        assert found != null : "could not find foreign call named " + name + " in " + stubClass;

        List<Class<?>> paramList = Arrays.asList(found.getParameterTypes());

        Class<?>[] cCallTypes = paramList.subList(1, paramList.size()).toArray(new Class<?>[paramList.size() - 1]);

        return new ForeignCallDescriptor(name, found.getReturnType(), cCallTypes);

    }

    /**

     * Determines if this is a HotSpot build where the ASSERT mechanism is enabled.

     */

    @Fold

    public static boolean cAssertionsEnabled(@InjectedParameter GraalHotSpotVMConfig config) {

        return config.cAssertions;

    }

    @NodeIntrinsic(StubForeignCallNode.class)

    private static native void vmMessageC(@ConstantNodeParameter ForeignCallDescriptor stubPrintfC, boolean vmError, Word format, long v1, long v2, long v3);

    /**

     * Prints a message to the log stream.

     * <p>

     * <b>Stubs must use this instead of {@link Log#printf(String, long)} to avoid an object

     * constant in a RuntimeStub.</b>

     *

     * @param message a message string

     */

    public static void printf(String message) {

        vmMessageC(VM_MESSAGE_C, false, cstring(message), 0L, 0L, 0L);

    }

    /**

     * Prints a message to the log stream.

     * <p>

     * <b>Stubs must use this instead of {@link Log#printf(String, long)} to avoid an object

     * constant in a RuntimeStub.</b>

     *

     * @param format a C style printf format value

     * @param value the value associated with the first conversion specifier in {@code format}

     */

    public static void printf(String format, long value) {

        vmMessageC(VM_MESSAGE_C, false, cstring(format), value, 0L, 0L);

    }

    /**

     * Prints a message to the log stream.

     * <p>

     * <b>Stubs must use this instead of {@link Log#printf(String, long, long)} to avoid an object

     * constant in a RuntimeStub.</b>

     *

     * @param format a C style printf format value

     * @param v1 the value associated with the first conversion specifier in {@code format}

     * @param v2 the value associated with the second conversion specifier in {@code format}

     */

    public static void printf(String format, long v1, long v2) {

        vmMessageC(VM_MESSAGE_C, false, cstring(format), v1, v2, 0L);

    }

    /**

     * Prints a message to the log stream.

     * <p>

     * <b>Stubs must use this instead of {@link Log#printf(String, long, long, long)} to avoid an

     * object constant in a RuntimeStub.</b>

     *

     * @param format a C style printf format value

     * @param v1 the value associated with the first conversion specifier in {@code format}

     * @param v2 the value associated with the second conversion specifier in {@code format}

     * @param v3 the value associated with the third conversion specifier in {@code format}

     */

    public static void printf(String format, long v1, long v2, long v3) {

        vmMessageC(VM_MESSAGE_C, false, cstring(format), v1, v2, v3);

    }

    /**

     * Analyzes a given value and prints information about it to the log stream.

     */

    public static void decipher(long value) {

        vmMessageC(VM_MESSAGE_C, false, WordFactory.zero(), value, 0L, 0L);

    }

    /**

     * Exits the VM with a given error message.

     * <p>

     * <b>Stubs must use this instead of {@link VMErrorNode#vmError(String, long)} to avoid an

     * object constant in a RuntimeStub.</b>

     *

     * @param message an error message

     */

    public static void fatal(String message) {

        vmMessageC(VM_MESSAGE_C, true, cstring(message), 0L, 0L, 0L);

    }

    /**

     * Exits the VM with a given error message.

     * <p>

     * <b>Stubs must use this instead of {@link Log#printf(String, long, long, long)} to avoid an

     * object constant in a RuntimeStub.</b>

     *

     * @param format a C style printf format value

     * @param value the value associated with the first conversion specifier in {@code format}

     */

    public static void fatal(String format, long value) {

        vmMessageC(VM_MESSAGE_C, true, cstring(format), value, 0L, 0L);

    }

    /**

     * Exits the VM with a given error message.

     * <p>

     * <b>Stubs must use this instead of {@link Log#printf(String, long, long, long)} to avoid an

     * object constant in a RuntimeStub.</b>

     *

     * @param format a C style printf format value

     * @param v1 the value associated with the first conversion specifier in {@code format}

     * @param v2 the value associated with the second conversion specifier in {@code format}

     */

    public static void fatal(String format, long v1, long v2) {

        vmMessageC(VM_MESSAGE_C, true, cstring(format), v1, v2, 0L);

    }

    /**

     * Exits the VM with a given error message.

     * <p>

     * <b>Stubs must use this instead of {@link Log#printf(String, long, long, long)} to avoid an

     * object constant in a RuntimeStub.</b>

     *

     * @param format a C style printf format value

     * @param v1 the value associated with the first conversion specifier in {@code format}

     * @param v2 the value associated with the second conversion specifier in {@code format}

     * @param v3 the value associated with the third conversion specifier in {@code format}

     */

    public static void fatal(String format, long v1, long v2, long v3) {

        vmMessageC(VM_MESSAGE_C, true, cstring(format), v1, v2, v3);

    }

    /**

     * Print {@code number} as decimal string to {@code buffer}.

     *

     * @param buffer

     * @param number

     * @return A pointer pointing one byte right after the last printed digit in {@code buffer}.

     */

    public static Word printNumber(Word buffer, long number) {

        long tmpNumber = number;

        int offset;

        if (tmpNumber <= 0) {

            tmpNumber = -tmpNumber;

            offset = 1;

        } else {

            offset = 0;

        }

        while (tmpNumber > 0) {

            tmpNumber /= 10;

            offset++;

        }

        tmpNumber = number < 0 ? -number : number;

        Word ptr = buffer.add(offset);

        do {

            long digit = tmpNumber % 10;

            tmpNumber /= 10;

            ptr = ptr.subtract(1);

            ptr.writeByte(0, (byte) ('0' + digit));

        } while (tmpNumber > 0);

        if (number < 0) {

            ptr = ptr.subtract(1);

            ptr.writeByte(0, (byte) '-');

        }

        return buffer.add(offset);

    }

    /**

     * Copy {@code javaString} bytes to the memory location {@code ptr}.

     *

     * @param buffer

     * @param javaString

     * @return A pointer pointing one byte right after the last byte copied from {@code javaString}

     *         to {@code ptr}

     */

    public static Word printString(Word buffer, String javaString) {

        Word string = cstring(javaString);

        int i = 0;

        byte b;

        while ((b = string.readByte(i)) != 0) {

            buffer.writeByte(i, b);

            i++;

        }

        return buffer.add(i);

    }

}