test/hotspot/jtreg/compiler/loopopts/TestCastIINoLoopLimitCheck.java

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/**
 * @test
 * @bug 8073184
 * @summary CastII that guards counted loops confuses range check elimination with LoopLimitCheck off
 *
 * @run main/othervm -XX:+IgnoreUnrecognizedVMOptions -Xcomp
 *      -XX:CompileCommand=compileonly,compiler.loopopts.TestCastIINoLoopLimitCheck::m
 *      compiler.loopopts.TestCastIINoLoopLimitCheck
 */

package compiler.loopopts;
/*
 * The test was originally run with
 *
 * -XX:+UnlockDiagnosticVMOptions -XX:-LoopLimitCheck
 *
 * to trigger a problem with code guarded with !LoopLimitCheck.
 * JDK-8072422 has removed that code but kept the test because the
 * test generates an interesting graph shape.
 */
public class TestCastIINoLoopLimitCheck {

    static void m(int i, int index, char[] buf) {
        while (i >= 65536) {
            i = i / 100;
            buf [--index] = 0;
            buf [--index] = 1;
        }
    }

    static public void main(String[] args) {
        m(0, 0, null);
    }
}