/*

 * Copyright (c) 2015, 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.replacements.test;

import org.graalvm.compiler.api.directives.GraalDirectives;

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

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

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

import org.graalvm.compiler.bytecode.BytecodeProvider;

import org.graalvm.compiler.nodes.ReturnNode;

import org.graalvm.compiler.nodes.StartNode;

import org.graalvm.compiler.nodes.StructuredGraph;

import org.graalvm.compiler.nodes.graphbuilderconf.InvocationPlugins;

import org.graalvm.compiler.nodes.graphbuilderconf.InvocationPlugins.Registration;

import org.graalvm.compiler.nodes.graphbuilderconf.NodeIntrinsicPluginFactory.InjectionProvider;

import org.graalvm.compiler.replacements.NodeIntrinsificationProvider;

import org.junit.Test;

public class FoldTest extends ReplacementsTest {

    private static class TestMethod {

        public static int test() {

            return 42;

        }

    }

    static class FoldUtils {

        private int number;

        FoldUtils(int number) {

            this.number = number;

        }

        @Fold

        static int multiply(int a, int b) {

            // we want to test whether @Fold works, so prevent automatic constant folding

            return a * GraalDirectives.opaque(b);

        }

        @Fold

        int getNumber() {

            // we want to test whether @Fold works, so prevent automatic constant folding

            return GraalDirectives.opaque(number);

        }

    }

    @ClassSubstitution(TestMethod.class)

    private static class TestMethodSubstitution {

        private static final FoldUtils utils = new FoldUtils(21);

        @MethodSubstitution

        public static int test() {

            return FoldUtils.multiply(utils.getNumber(), 2);

        }

    }

    @Override

    protected void registerInvocationPlugins(InvocationPlugins invocationPlugins) {

        InjectionProvider injection = new NodeIntrinsificationProvider(getMetaAccess(), getSnippetReflection(), getProviders().getForeignCalls(), null);

        new PluginFactory_FoldTest().registerPlugins(invocationPlugins, injection);

        BytecodeProvider replacementBytecodeProvider = getSystemClassLoaderBytecodeProvider();

        Registration r = new Registration(invocationPlugins, TestMethod.class, replacementBytecodeProvider);

        r.registerMethodSubstitution(TestMethodSubstitution.class, "test");

        super.registerInvocationPlugins(invocationPlugins);

    }

    public static int callTest() {

        return TestMethod.test();

    }

    @Override

    protected void checkHighTierGraph(StructuredGraph graph) {

        // check that folding happened correctly

        StartNode start = graph.start();

        assert start.next() instanceof ReturnNode : "expected ReturnNode, got " + start.next();

        ReturnNode ret = (ReturnNode) start.next();

        assert ret.result().isConstant() : "expected ConstantNode, got " + ret.result();

    }

    @Test

    public void snippetTest() {

        test("callTest");

    }

}