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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
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 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
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/**
 * @test
 * @bug 8295159
 * @summary DSO created with -ffast-math breaks Java floating-point arithmetic
 * @run main compiler.floatingpoint.TestDenormalFloat
 */

// gcc -g -ffast-math -shared -Lbuild/linux-x86_64-server-release/jdk/lib -ljava -o libfast-math.so libfast-math.c
// LD_LIBRARY_PATH=.:build/linux-x86_64-server-release/jdk/lib:build/linux-x86_64-server-release/jdk/lib/server/ java -cp /tmp compiler.floatingpoint.TestDenormalFloat
//
// Result:
// Loading libfast-math.so
// Exception in thread "main" java.lang.AssertionError: TEST FAILED: 0.0
// 	at compiler.floatingpoint.TestDenormalFloat.testFloats(TestDenormalFloat.java:47)
// 	at compiler.floatingpoint.TestDenormalFloat.main(TestDenormalFloat.java:57)


package compiler.floatingpoint;

import static java.lang.System.loadLibrary;

public class TestDenormalFloat {
    static volatile float lastFloat;

    private static void testFloats() {
        lastFloat = 0x1.0p-149f;
        for (float x = lastFloat * 2; x <= 0x1.0p127f; x *= 2) {
            if (x != x || x <= lastFloat) {
                throw new AssertionError("TEST FAILED: " + x);
            }
            lastFloat = x;
        }
    }

    public static void main(String[] args) {
        testFloats();
        System.out.println("Loading libfast-math.so");
        loadLibrary("fast-math");
        testFloats();
        System.out.println("Test passed.");
    }
}