/*

 * Copyright (c) 2011, 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.core.test;

import java.io.BufferedInputStream;

import java.io.ByteArrayInputStream;

import java.io.FileInputStream;

import java.io.IOException;

import java.io.InputStream;

import org.graalvm.compiler.debug.DebugContext;

import org.graalvm.compiler.debug.TTY;

import org.graalvm.compiler.graph.Node;

import org.graalvm.compiler.nodeinfo.Verbosity;

import org.graalvm.compiler.nodes.AbstractMergeNode;

import org.graalvm.compiler.nodes.PhiNode;

import org.graalvm.compiler.nodes.StructuredGraph;

import org.graalvm.compiler.nodes.StructuredGraph.AllowAssumptions;

import org.graalvm.compiler.nodes.StructuredGraph.ScheduleResult;

import org.graalvm.compiler.nodes.cfg.Block;

import org.graalvm.compiler.nodes.java.InstanceOfNode;

import org.graalvm.compiler.phases.common.CanonicalizerPhase;

import org.graalvm.compiler.phases.common.ConditionalEliminationPhase;

import org.graalvm.compiler.phases.schedule.SchedulePhase;

import org.junit.Assert;

import org.junit.Ignore;

import org.junit.Test;

/**

 * In the following tests, the scalar type system of the compiler should be complete enough to see

 * the relation between the different conditions.

 */

public class TypeSystemTest extends GraalCompilerTest {

    @Test

    public void test3() {

        test("test3Snippet", "referenceSnippet3");

    }

    public static int referenceSnippet3(Object o) {

        if (o == null) {

            return 1;

        } else {

            return 2;

        }

    }

    @SuppressWarnings("unused")

    public static int test3Snippet(Object o) {

        if (o == null) {

            if (o != null) {

                return 3;

            } else {

                return 1;

            }

        } else {

            return 2;

        }

    }

    @Test

    public void test4() {

        test("test4Snippet", "referenceSnippet3");

    }

    @SuppressWarnings("unused")

    public static int test4Snippet(Object o) {

        if (o == null) {

            Object o2 = Integer.class;

            if (o == o2) {

                return 3;

            } else {

                return 1;

            }

        } else {

            return 2;

        }

    }

    @Test

    @Ignore

    public void test5() {

        test("test5Snippet", "referenceSnippet5");

    }

    public static int referenceSnippet5(Object o, Object a) {

        if (o == null) {

            if (a == Integer.class) {

                return 1;

            }

        } else {

            if (a == Double.class) {

                return 11;

            }

        }

        if (a == Integer.class) {

            return 3;

        }

        return 5;

    }

    @SuppressWarnings("unused")

    public static int test5Snippet(Object o, Object a) {

        if (o == null) {

            if (a == Integer.class) {

                if (a == null) {

                    return 10;

                }

                return 1;

            }

        } else {

            if (a == Double.class) {

                if (a != null) {

                    return 11;

                }

                return 2;

            }

        }

        if (a == Integer.class) {

            return 3;

        }

        return 5;

    }

    @Test

    public void test6() {

        testHelper("test6Snippet", InstanceOfNode.class);

    }

    public static int test6Snippet(int i) throws IOException {

        Object o = null;

        if (i == 5) {

            o = new FileInputStream("asdf");

        }

        if (i < 10) {

            o = new ByteArrayInputStream(new byte[]{1, 2, 3});

        }

        if (i > 0) {

            o = new BufferedInputStream(null);

        }

        return ((InputStream) o).available();

    }

    @Test

    public void test7() {

        test("test7Snippet", "referenceSnippet7");

    }

    public static int test7Snippet(int x) {

        return ((x & 0xff) << 10) == ((x & 0x1f) + 1) ? 0 : x;

    }

    public static int referenceSnippet7(int x) {

        return x;

    }

    private void test(String snippet, String referenceSnippet) {

        StructuredGraph graph = parseEager(snippet, AllowAssumptions.NO);

        DebugContext debug = graph.getDebug();

        debug.dump(DebugContext.BASIC_LEVEL, graph, "Graph");

        /*

         * When using FlowSensitiveReductionPhase instead of ConditionalEliminationPhase,

         * tail-duplication gets activated thus resulting in a graph with more nodes than the

         * reference graph.

         */

        new ConditionalEliminationPhase(false).apply(graph, getProviders());

        new CanonicalizerPhase().apply(graph, getProviders());

        // a second canonicalizer is needed to process nested MaterializeNodes

        new CanonicalizerPhase().apply(graph, getProviders());

        StructuredGraph referenceGraph = parseEager(referenceSnippet, AllowAssumptions.NO);

        new ConditionalEliminationPhase(false).apply(referenceGraph, getProviders());

        new CanonicalizerPhase().apply(referenceGraph, getProviders());

        new CanonicalizerPhase().apply(referenceGraph, getProviders());

        assertEquals(referenceGraph, graph);

    }

    @Override

    protected void assertEquals(StructuredGraph expected, StructuredGraph graph) {

        DebugContext debug = graph.getDebug();

        if (getNodeCountExcludingUnusedConstants(expected) != getNodeCountExcludingUnusedConstants(graph)) {

            debug.dump(DebugContext.BASIC_LEVEL, expected, "expected (node count)");

            debug.dump(DebugContext.BASIC_LEVEL, graph, "graph (node count)");

            Assert.fail("Graphs do not have the same number of nodes: " + expected.getNodeCount() + " vs. " + graph.getNodeCount());

        }

    }

    public static void outputGraph(StructuredGraph graph, String message) {

        TTY.println("========================= " + message);

        SchedulePhase schedulePhase = new SchedulePhase(graph.getOptions());

        schedulePhase.apply(graph);

        ScheduleResult schedule = graph.getLastSchedule();

        for (Block block : schedule.getCFG().getBlocks()) {

            TTY.print("Block " + block + " ");

            if (block == schedule.getCFG().getStartBlock()) {

                TTY.print("* ");

            }

            TTY.print("-> ");

            for (Block succ : block.getSuccessors()) {

                TTY.print(succ + " ");

            }

            TTY.println();

            for (Node node : schedule.getBlockToNodesMap().get(block)) {

                outputNode(node);

            }

        }

    }

    private static void outputNode(Node node) {

        TTY.print("  " + node + "    (usage count: " + node.getUsageCount() + ") (inputs:");

        for (Node input : node.inputs()) {

            TTY.print(" " + input.toString(Verbosity.Id));

        }

        TTY.println(")");

        if (node instanceof AbstractMergeNode) {

            for (PhiNode phi : ((AbstractMergeNode) node).phis()) {

                outputNode(phi);

            }

        }

    }

    private <T extends Node> void testHelper(String snippet, Class<T> clazz) {

        StructuredGraph graph = parseEager(snippet, AllowAssumptions.NO);

        new CanonicalizerPhase().apply(graph, getProviders());

        new CanonicalizerPhase().apply(graph, getProviders());

        DebugContext debug = graph.getDebug();

        debug.dump(DebugContext.BASIC_LEVEL, graph, "Graph " + snippet);

        Assert.assertFalse("shouldn't have nodes of type " + clazz, graph.getNodes().filter(clazz).iterator().hasNext());

    }

}