jdk-24/test/hotspot/jtreg/compiler/c2/irTests/MulINodeIdealizationTests.java

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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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package compiler.c2.irTests;

import jdk.test.lib.Asserts;
import compiler.lib.ir_framework.*;

/*
 * @test
 * @bug 8267265
 * @summary Test that Ideal transformations of MulINode* are being performed as expected.
 * @library /test/lib /
 * @run driver compiler.c2.irTests.MulINodeIdealizationTests
 */
public class MulINodeIdealizationTests {
    public static void main(String[] args) {
        TestFramework.run();
    }

    @Run(test = {"combineConstants", "moveConstants", "moveConstantsAgain",
                 "multiplyZero", "multiplyZeroAgain", "distribute",
                 "identity",  "identityAgain", "powerTwo",
                 "powerTwoAgain", "powerTwoPlusOne", "powerTwoMinusOne",
                 "negativeCancelledOut", "maxMin"})
    public void runMethod() {
        int a = RunInfo.getRandom().nextInt();
        int b = RunInfo.getRandom().nextInt();

        int min = Integer.MIN_VALUE;
        int max = Integer.MAX_VALUE;

        assertResult(0, 0);
        assertResult(a, b);
        assertResult(min, min);
        assertResult(max, max);
    }

    @DontCompile
    public void assertResult(int a, int b) {
        Asserts.assertEQ((a * 13) * 14                  , combineConstants(a));
        Asserts.assertEQ((a * 13) * b                   , moveConstants(a, b));
        Asserts.assertEQ(a * (b * 13)                   , moveConstantsAgain(a, b));
        Asserts.assertEQ(0 * a                          , multiplyZero(a));
        Asserts.assertEQ(a * 0                          , multiplyZeroAgain(a));
        Asserts.assertEQ((13 + a) * 14                  , distribute(a));
        Asserts.assertEQ(1 * a                          , identity(a));
        Asserts.assertEQ(a * 1                          , identityAgain(a));
        Asserts.assertEQ(a * 64                         , powerTwo(a));
        Asserts.assertEQ(a * (1025 - 1)                 , powerTwoAgain(a));
        Asserts.assertEQ(a * (64 + 1)                   , powerTwoPlusOne(a));
        Asserts.assertEQ(a * (64 - 1)                   , powerTwoMinusOne(a));
        Asserts.assertEQ((0 - a) * (0 - b)              , negativeCancelledOut(a, b));
        Asserts.assertEQ(Math.max(a, b) * Math.min(a, b), maxMin(a, b));
    }

    @Test
    @IR(counts = {IRNode.MUL, "1"})
    //Checks (x * c1) * c2 => x * c3 where c3 = c1 * c2
    public int combineConstants(int x){
        return (x * 13) * 14;
    }

    @Test
    @IR(counts = {IRNode.MUL, "2"})
    // Checks (x * c1) * y => (x * y) * c1
    public int moveConstants(int x, int y) {
        return (x * 13) * y;
    }

    @Test
    @IR(counts = {IRNode.MUL, "2"})
    // Checks x * (y * c1) => (x * y) * c1
    public int moveConstantsAgain(int x, int y) {
        return x * (y * 13);
    }

    @Test
    @IR(failOn = {IRNode.MUL})
    // Checks 0 * x => 0
    public int multiplyZero(int x) {
        return 0 * x;
    }

    @Test
    @IR(failOn = {IRNode.MUL})
    // Checks x * 0 => 0
    public int multiplyZeroAgain(int x) {
        return x * 0;
    }

    @Test
    @IR(counts = {IRNode.MUL, "1",
                  IRNode.ADD, "1",
                 })
    // Checks (c1 + x) * c2 => x * c2 + c3 where c3 = c1 * c2
    public int distribute(int x) {
        return (13 + x) * 14;
    }

    @Test
    @IR(failOn = {IRNode.MUL})
    // Checks 1 * x => x
    public int identity(int x) {
        return 1 * x;
    }

    @Test
    @IR(failOn = {IRNode.MUL})
    // Checks x * 1 => x
    public int identityAgain(int x) {
        return x * 1;
    }

    @Test
    @IR(failOn = {IRNode.MUL})
    @IR(counts = {IRNode.LSHIFT, "1"})
    // Checks x * 2^n => x << n
    public int powerTwo(int x) {
        return x * 64;
    }

    @Test
    @IR(failOn = {IRNode.SUB, IRNode.MUL})
    @IR(counts = {IRNode.LSHIFT, "1"})
    // Checks x * 2^n => x << n
    public int powerTwoAgain(int x) {
        return x * (1025 - 1);
    }

    @Test
    @IR(failOn = {IRNode.MUL})
    @IR(counts = {IRNode.LSHIFT, "1",
                  IRNode.ADD, "1",
                 })
    // Checks x * (2^n + 1) => (x << n) + x
    public int powerTwoPlusOne(int x) {
        return x * (64 + 1);
    }

    @Test
    @IR(failOn = {IRNode.MUL})
    @IR(counts = {IRNode.LSHIFT, "1",
                  IRNode.SUB, "1",
                 })
    // Checks x * (2^n - 1) => (x << n) - x
    public int powerTwoMinusOne(int x) {
        return x * (64 - 1);
    }

    @Test
    @IR(failOn = { IRNode.SUB })
    @IR(counts = { IRNode.MUL, "1" })
    // Checks (0 - x) * (0 - y) => x * y
    public int negativeCancelledOut(int x, int y) {
        return (0 - x) * (0 - y);
    }

    @Test
    @IR(failOn = { IRNode.MAX, IRNode.MIN })
    @IR(counts = { IRNode.MUL, "1" })
    // Checks Math.max(x, y) * Math.min(x, y) => x * y
    public int maxMin(int x, int y) {
        return Math.max(x, y) * Math.min(x, y);
    }
}