On big-endian systems (tested on s390x, and PPC-BE), reinterpretation operations yield incorrect results.

Test program:

// compile: javac --add-modules jdk.incubator.vector Reproducer.java
// run: java --add-modules jdk.incubator.vector Reproducer

import jdk.incubator.vector.*;

public class Reproducer {
    public static void main(String[] args) {
        LongVector v1 = LongVector.fromArray(LongVector.SPECIES_128,
            new long[]{(2L << 32) | 1L, (4L << 32) | 3L}, 0);
        // v1 = {0x0000000200000001, 0x0000000400000003}

        IntVector result = v1.reinterpretAsInts();
        // Expected result: [1, 2, 3, 4]
        // Actual result on big-endian platforms: [2, 1, 4, 3]

        System.out.println(result);
    }
}


Source: https://github.com/andreaTP/s390x-vector-bug-reproducer
OpenJ9 Discussion: https://github.com/eclipse-openj9/openj9/issues/22821