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 *

 * This code is free software; you can redistribute it and/or modify it

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 * published by the Free Software Foundation.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

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 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

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 *

 * You should have received a copy of the GNU General Public License version

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package org.graalvm.compiler.core.test;

import org.graalvm.compiler.loop.DefaultLoopPolicies;

import org.graalvm.compiler.loop.phases.LoopPeelingPhase;

import org.graalvm.compiler.nodes.ReturnNode;

import org.graalvm.compiler.nodes.StructuredGraph;

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

import org.graalvm.compiler.nodes.ValueNode;

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

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

import org.graalvm.compiler.phases.tiers.HighTierContext;

import org.graalvm.compiler.virtual.phases.ea.PartialEscapePhase;

import org.junit.Assert;

import org.junit.Ignore;

import org.junit.Test;

/**

 * In the following tests, the usages of local variable "a" are replaced with the integer constant

 * 0. Then boxing elimination is applied and it is verified that the resulting graph is equal to the

 * graph of the method that just has a "return 1" statement in it.

 */

public class BoxingEliminationTest extends GraalCompilerTest {

    private static final Short s = 2;

    @SuppressWarnings("all")

    public static short referenceSnippet1() {

        return 1;

    }

    @SuppressWarnings("all")

    public static short referenceSnippet2() {

        return 2;

    }

    public static Short boxedShort() {

        return 1;

    }

    public static Object boxedObjectShort() {

        return (short) 1;

    }

    public static Object boxedObjectInteger() {

        return 1;

    }

    public static Integer boxedInteger() {

        return 2;

    }

    public static Short constantBoxedShort() {

        return s;

    }

    @Test

    public void test1() {

        compareGraphs("test1Snippet", "referenceSnippet1");

    }

    @SuppressWarnings("all")

    public static short test1Snippet() {

        return boxedShort();

    }

    @Test

    public void test2() {

        compareGraphs("test2Snippet", "referenceSnippet1");

    }

    @SuppressWarnings("all")

    public static short test2Snippet() {

        return (Short) boxedObjectShort();

    }

    @Test

    public void test3() {

        compareGraphs("test3Snippet", "referenceSnippet1");

    }

    @SuppressWarnings("all")

    public static short test3Snippet() {

        short b = boxedShort();

        if (b < 0) {

            b = boxedShort();

        }

        return b;

    }

    @Test

    public void test4() {

        compareGraphs("test4Snippet", "referenceSnippet2");

    }

    @SuppressWarnings("all")

    public static short test4Snippet() {

        return constantBoxedShort();

    }

    @Ignore

    @Test

    public void testLoop() {

        compareGraphs("testLoopSnippet", "referenceLoopSnippet", false, true);

    }

    public static int testLoopSnippet(int n, int a) {

        Integer sum = a;

        for (Integer i = 0; i < n; i++) {

            sum += i;

        }

        return sum;

    }

    public static int referenceLoopSnippet(int n, int a) {

        int sum = a;

        for (int i = 0; i < n; i++) {

            sum += i;

        }

        return sum;

    }

    @Test

    public void testLoop2() {

        compareGraphs("testLoop2Snippet", "referenceLoop2Snippet", true, true);

    }

    public static int testLoop2Snippet(int n, Integer a) {

        Integer sum = a;

        for (Integer i = 0; i < n; i++) {

            sum += i;

        }

        return sum;

    }

    public static int referenceLoop2Snippet(int n, Integer a) {

        Integer sum0;

        if (n <= 0) {

            sum0 = a;

        } else {

            int sum = a;

            for (int i = 1; i < n; i++) {

                sum += i;

            }

            sum0 = sum;

        }

        return sum0;

    }

    public static int referenceIfSnippet(int a) {

        int result;

        if (a < 0) {

            result = 2;

        } else {

            result = 1;

        }

        return result;

    }

    @Test

    public void testIf() {

        compareGraphs("testIfSnippet", "referenceIfSnippet");

    }

    public static int testIfSnippet(int a) {

        Integer result;

        if (a < 0) {

            result = boxedInteger();

        } else {

            result = (Integer) boxedObjectInteger();

        }

        return result;

    }

    @Test

    public void testComparison() {

        compareGraphs("testComparison1Snippet", "referenceComparisonSnippet");

        compareGraphs("testComparison2Snippet", "referenceComparisonSnippet");

    }

    @SuppressWarnings("cast")

    public static boolean testComparison1Snippet(int a, int b) {

        return ((Integer) a) == b;

    }

    public static boolean testComparison2Snippet(int a, int b) {

        Integer x = a;

        Integer y = b;

        return x == y;

    }

    public static boolean referenceComparisonSnippet(int a, int b) {

        return a == b;

    }

    @Test

    public void testLateCanonicalization() {

        compareGraphs("testLateCanonicalizationSnippet", "referenceLateCanonicalizationSnippet");

    }

    public static boolean testLateCanonicalizationSnippet(int a) {

        Integer x = a;

        Integer y = 1000;

        return x == y;

    }

    public static boolean referenceLateCanonicalizationSnippet(int a) {

        return a == 1000;

    }

    private StructuredGraph graph;

    public static Integer materializeReferenceSnippet(int a) {

        return Integer.valueOf(a);

    }

    public static Integer materializeTest1Snippet(int a) {

        Integer v = a;

        if (v == a) {

            return v;

        } else {

            return null;

        }

    }

    @Test

    public void materializeTest1() {

        test("materializeTest1Snippet", 1);

    }

    public static int intTest1Snippet() {

        return Integer.valueOf(1);

    }

    @Test

    public void intTest1() {

        ValueNode result = getResult("intTest1Snippet");

        Assert.assertTrue(result.isConstant());

        Assert.assertEquals(1, result.asJavaConstant().asInt());

    }

    public static int mergeTest1Snippet(boolean d, int a, int b) {

        Integer v;

        if (d) {

            v = a;

        } else {

            v = b;

        }

        return v;

    }

    @Test

    public void mergeTest1() {

        processMethod("mergeTest1Snippet");

    }

    public static boolean equalsTest1Snippet(int x, int y) {

        Integer a = x;

        Integer b = y;

        return a == b;

    }

    @Test

    public void equalsTest1() {

        processMethod("equalsTest1Snippet");

    }

    public static int loopTest1Snippet(int n, int v) {

        Integer sum = 0;

        for (int i = 0; i < n; i++) {

            sum += v;

        }

        return sum;

    }

    @Test

    public void loopTest1() {

        processMethod("loopTest1Snippet");

    }

    final ValueNode getResult(String snippet) {

        processMethod(snippet);

        assertDeepEquals(1, graph.getNodes(ReturnNode.TYPE).count());

        return graph.getNodes(ReturnNode.TYPE).first().result();

    }

    private void processMethod(final String snippet) {

        graph = parseEager(snippet, AllowAssumptions.NO);

        HighTierContext context = getDefaultHighTierContext();

        createInliningPhase().apply(graph, context);

    }

    private void compareGraphs(final String snippet, final String referenceSnippet) {

        compareGraphs(snippet, referenceSnippet, false, false);

    }

    private void compareGraphs(final String snippet, final String referenceSnippet, final boolean loopPeeling, final boolean excludeVirtual) {

        graph = parseEager(snippet, AllowAssumptions.NO);

        HighTierContext context = getDefaultHighTierContext();

        canonicalizer.apply(graph, context);

        createInliningPhase().apply(graph, context);

        if (loopPeeling) {

            new LoopPeelingPhase(new DefaultLoopPolicies()).apply(graph, context);

        }

        new DeadCodeEliminationPhase().apply(graph);

        canonicalizer.apply(graph, context);

        new PartialEscapePhase(false, canonicalizer, graph.getOptions()).apply(graph, context);

        new DeadCodeEliminationPhase().apply(graph);

        canonicalizer.apply(graph, context);

        StructuredGraph referenceGraph = parseEager(referenceSnippet, AllowAssumptions.YES);

        createInliningPhase().apply(referenceGraph, context);

        new DeadCodeEliminationPhase().apply(referenceGraph);

        assertEquals(referenceGraph, graph, excludeVirtual, true);

    }

}