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package compiler.c2.irTests;

import jdk.test.lib.Asserts;
import jdk.test.lib.Utils;

import compiler.lib.ir_framework.*;

/*
 * @test
 * @bug 8345766 8378742
 * @key randomness
 * @summary Test that Ideal transformations of ModDNode are being performed as expected.
 * @library /test/lib /
 * @run driver compiler.c2.irTests.ModDNodeTests
 */
public class ModDNodeTests {
    public static final double q = Utils.getRandomInstance().nextDouble() * 100.0d;
    public static volatile int volatileField;

    public static void main(String[] args) {
        TestFramework.run();
    }

    @Run(test = {"constant", "notConstant", "veryNotConstant",
            "unusedResult",
            "repeatedlyUnused",
            "unusedResultAfterLoopOpt1",
            "unusedResultAfterLoopOpt2",
            "unusedResultAfterLoopOpt3",
            "constantFoldInCCP"
    })
    public void runMethod() {
        Asserts.assertEQ(constant(), q % 72.0d % 30.0d);
        Asserts.assertEQ(alsoConstant(), q % 31.432d);
        Asserts.assertTrue(Double.isNaN(nanLeftConstant()));
        Asserts.assertTrue(Double.isNaN(nanRightConstant()));
        Asserts.assertEQ(notConstant(37.5d), 37.5d % 32.0d);
        Asserts.assertEQ(veryNotConstant(531.25d, 14.5d), 531.25d % 32.0d % 14.5d);
        unusedResult(1.1d, 2.2d);
        repeatedlyUnused(1.1d, 2.2d);
        Asserts.assertEQ(unusedResultAfterLoopOpt1(1.1d, 2.2d), 0.d);
        Asserts.assertEQ(unusedResultAfterLoopOpt2(1.1d, 2.2d), 0.d);
        Asserts.assertEQ(unusedResultAfterLoopOpt3(1.1d, 2.2d), 0.d);
        Asserts.assertEQ(constantFoldInCCP(), 4.0d);
    }

    // Note: we used to check for ConD nodes in the IR. But that is a bit brittle:
    // Constant nodes can appear during IR transformations, and then lose their outputs.
    // During IGNV, the constants stay in the graph even if they lose the inputs. But
    // CCP cleans them out because they are not in the useful set. So for now, we do not
    // rely on any constant counting, just on counting the operation nodes.

    @Test
    @IR(counts = {IRNode.MOD_D, "2"},
        phase = CompilePhase.AFTER_PARSING)
    @IR(failOn = {".*CallLeaf.*drem.*"},
        phase = CompilePhase.BEFORE_MATCHING)
    public double constant() {
        // All constants available during parsing
        return q % 72.0d % 30.0d;
    }

    @Test
    @IR(counts = {IRNode.MOD_D, "1"},
        phase = CompilePhase.AFTER_PARSING)
    @IR(counts = {IRNode.MOD_D, "1"},
        phase = CompilePhase.PHASEIDEALLOOP1) // Only constant fold after some loop opts
    @IR(failOn = {".*CallLeaf.*drem.*"},
        phase = CompilePhase.BEFORE_MATCHING)
    public double alsoConstant() {
        // Make sure value is only available after second loop opts round
        double val = 0;
        for (int i = 0; i < 4; i++) {
            if ((i % 2) == 0) {
                val = q;
            }
        }
        return val % 31.432d;
    }

    @Test
    @IR(counts = {IRNode.MOD_D, "2"},
        phase = CompilePhase.AFTER_PARSING)
    @IR(counts = {IRNode.MOD_D, "2"},
        phase = CompilePhase.PHASEIDEALLOOP1) // Only constant fold after some loop opts
    @IR(failOn = {".*CallLeaf.*drem.*"},
        phase = CompilePhase.BEFORE_MATCHING)
    public double nanLeftConstant() {
        // Make sure value is only available after second loop opts round
        double val = 134.18d;
        for (int i = 0; i < 4; i++) {
            if ((i % 2) == 0) {
                val = Double.NaN;
            }
        }
        return 56.234d % (val % 31.432d);
    }

    @Test
    @IR(counts = {IRNode.MOD_D, "2"},
        phase = CompilePhase.AFTER_PARSING)
    @IR(counts = {IRNode.MOD_D, "2"},
        phase = CompilePhase.PHASEIDEALLOOP1) // Only constant fold after some loop opts
    @IR(failOn = {".*CallLeaf.*drem.*"},
        phase = CompilePhase.BEFORE_MATCHING)
    public double nanRightConstant() {
        // Make sure value is only available after second loop opts round
        double val = 134.18d;
        for (int i = 0; i < 4; i++) {
            if ((i % 2) == 0) {
                val = Double.NaN;
            }
        }
        return 56.234d % (31.432d % val);
    }

    @Test
    @IR(counts = {IRNode.MOD_D, "1"},
        phase = CompilePhase.AFTER_PARSING)
    @IR(counts = {".*CallLeaf.*drem.*", "1"},
        phase = CompilePhase.BEFORE_MATCHING) // no constant folding
    public double notConstant(double x) {
        return x % 32.0d;
    }

    @Test
    @IR(counts = {IRNode.MOD_D, "2"},
        phase = CompilePhase.AFTER_PARSING)
    @IR(counts = {".*CallLeaf.*drem.*", "2"},
        phase = CompilePhase.BEFORE_MATCHING) // no constant folding
    public double veryNotConstant(double x, double y) {
        return x % 32.0d % y;
    }

    @Test
    @IR(counts = {IRNode.MOD_D, "1"},
        phase = CompilePhase.AFTER_PARSING)
    @IR(counts = {IRNode.MOD_D, "0"},
        phase = CompilePhase.ITER_GVN1) // IGVN removes unused nodes
    @IR(failOn = {".*CallLeaf.*drem.*"},
        phase = CompilePhase.BEFORE_MATCHING)
    public void unusedResult(double x, double y) {
        double unused = x % y;
    }

    @Test
    @IR(counts = {IRNode.MOD_D, "1"},
        phase = CompilePhase.AFTER_PARSING)
    @IR(failOn = {IRNode.MOD_D},
        phase = CompilePhase.ITER_GVN1) // IGVN removes unused nodes
    @IR(failOn = {".*CallLeaf.*drem.*"},
        phase = CompilePhase.BEFORE_MATCHING)
    public void repeatedlyUnused(double x, double y) {
        double unused = 1.d;
        for (int i = 0; i < 100_000; i++) {
            unused = x % y;
        }
    }

    // The difference between unusedResultAfterLoopOpt1 and unusedResultAfterLoopOpt2
    // is that they exercise a slightly different reason why the node is being removed,
    // and thus a different execution path. In unusedResultAfterLoopOpt1 the modulo is
    // used in the traps of the parse predicates. In unusedResultAfterLoopOpt2, it is not.
    @Test
    @IR(counts = {IRNode.MOD_D, "1"},
        phase = CompilePhase.AFTER_PARSING)
    @IR(counts = {IRNode.MOD_D, "1"},
        phase = CompilePhase.ITER_GVN2)
    @IR(failOn = {IRNode.MOD_D},
        phase = CompilePhase.BEFORE_MACRO_EXPANSION)
    @IR(failOn = {".*CallLeaf.*drem.*"},
        phase = CompilePhase.BEFORE_MATCHING)
    public double unusedResultAfterLoopOpt1(double x, double y) {
        double unused = x % y;

        int a = 77;
        int b = 0;
        do {
            a--;
            b++;
        } while (a > 0);

        if (b == 78) { // dead
            return unused;
        }
        return 0.d;
    }

    @Test
    @IR(counts = {IRNode.MOD_D, "1"},
        phase = CompilePhase.AFTER_PARSING)
    @IR(counts = {IRNode.MOD_D, "1"},
        phase = CompilePhase.AFTER_CLOOPS)
    @IR(failOn = {IRNode.MOD_D},
        phase = CompilePhase.PHASEIDEALLOOP1)
    @IR(failOn = {".*CallLeaf.*drem.*"},
        phase = CompilePhase.BEFORE_MATCHING)
    public double unusedResultAfterLoopOpt2(double x, double y) {
        int a = 77;
        int b = 0;
        do {
            a--;
            b++;
        } while (a > 0);

        double unused = x % y;

        if (b == 78) { // dead
            return unused;
        }
        return 0.d;
    }

    @Test
    @IR(counts = {IRNode.MOD_D, "3"},
        phase = CompilePhase.AFTER_PARSING)
    @IR(counts = {IRNode.MOD_D, "2"},
        phase = CompilePhase.AFTER_CLOOPS) // drop the useless one
    @IR(failOn = {IRNode.MOD_D},
        phase = CompilePhase.PHASEIDEALLOOP1) // drop the rest
    @IR(failOn = {".*CallLeaf.*drem.*"},
        phase = CompilePhase.BEFORE_MATCHING)
    public double unusedResultAfterLoopOpt3(double x, double y) {
        double unused = x % y;

        int a = 77;
        int b = 0;
        do {
            a--;
            b++;
        } while (a > 0);

        int other = (b - 77) * (int)(x % y % 1.d);
        return (double)other;
    }

    @Test
    @IR(failOn = {IRNode.CMP_D},
        phase = CompilePhase.CCP1)
    @IR(failOn = {IRNode.MOD_D},
        phase = CompilePhase.BEFORE_MACRO_EXPANSION)
    public double constantFoldInCCP(){
        int i;
        for (i = 2; i < 4; i *= 2) {
        }
        int j;
        for (j = 2; j < 4; j *= 2) {
        }
        volatileField = 42;
        double v1 = (double) i / 2;
        double v2 = j;
        double v = v1 % v2;
        for (; v < v2; v *= 2) {
        }
        return v;
    }
}