jdk/test/hotspot/jtreg/compiler/c2/TestMaskAndRShiftReorder.java

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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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/*
 * @test
 * @bug 8361700 8371534
 * @summary An expression of the form "(x & mask) >> shift", where the mask
 *          is a constant, should be transformed to "(x >> shift) & (mask >> shift)"
 *          VerifyIterativeGVN checks that this optimization was applied
 * @run main/othervm -Xcomp -XX:+IgnoreUnrecognizedVMOptions
 *      -XX:CompileCommand=compileonly,compiler.c2.TestMaskAndRShiftReorder::test*
 *      -XX:VerifyIterativeGVN=1110 compiler.c2.TestMaskAndRShiftReorder
 * @run main compiler.c2.TestMaskAndRShiftReorder
 *
 */

package compiler.c2;

public class TestMaskAndRShiftReorder {
    static long lFld;


    public static void main(String[] strArr) {
        // No known reproducer with URShiftI so far
        testRShiftI();
        testRShiftL();
        testURShiftL();
    }

    static void testRShiftI() {
        int x = 10;
        int y = -17;
        for (int i = 1; i < 7; i++) {
            for (int j = 1; j < 2; j++) {
                x <<= lFld;
            }
            y &= x;
            y >>= 1;
        }
    }

    static void testRShiftL() {
        long x = 10;
        long y = -17L;
        for (int i = 1; i < 7; i++) {
            for (int j = 1; j < 2; j++) {
                x <<= lFld;
            }
            y &= x;
            y >>= 1;
        }
    }

    static void testURShiftL() {
        long x = 10;
        long y = -17L;
        for (int i = 1; i < 7; i++) {
            for (int j = 1; j < 2; j++) {
                x <<= lFld;
            }
            y &= x;
            y >>>= 1;
        }
    }
}