Graal and JDK11

[Paul Woegerer]

A while back I added support for Java 11 based image building into native image.

    https://github.com/oracle/graal/commit/ed5f5f82d2962e5f65b3ee784a0cd62c489c41c5

Since then we build images on Java 11 as part of our regular gate tasks. E.g. See:

    https://travis-ci.org/oracle/graal/jobs/521993959

If you checkout master and run:

    [master $%=] ~/OLabs/git/svm-master/graal/substratevm> cat Hello.java
    public class Hello {
        public static void main(String[] args) {
            var javaVersion = System.getProperty("java.version");
            System.out.println("Hello Java " + javaVersion);
        }
    }

    [master $%=] ~/OLabs/git/svm-master/graal/substratevm> java --version
    openjdk 11.0.2 2019-01-15
    OpenJDK Runtime Environment 18.9 (build 11.0.2+7)
    OpenJDK 64-Bit Server VM 18.9 (build 11.0.2+7, mixed mode, sharing)

    [master $%=] ~/OLabs/git/svm-master/graal/substratevm> javac Hello.java

    [master $%=] ~/OLabs/git/svm-master/graal/substratevm> mx native-image Hello
    [hello:19205]    classlist:   1,607.95 ms
    WARNING: An illegal reflective access operation has occurred
    WARNING: Illegal reflective access by com.oracle.svm.core.jdk.FileTypeDetectorFeature (file:/home/pwoegere/OLabs/git/svm-master/graal/substratevm/mxbuild/dists/jdk9/svm.jar) to field java.nio.file.Files$FileTypeDetectors.installedDetectors
    WARNING: Please consider reporting this to the maintainers of com.oracle.svm.core.jdk.FileTypeDetectorFeature
    WARNING: Use --illegal-access=warn to enable warnings of further illegal reflective access operations
    WARNING: All illegal access operations will be denied in a future release
    [hello:19205]        (cap):     854.96 ms
    [hello:19205]        setup:   1,985.61 ms
    Warning: RecomputeFieldValue.FieldOffset automatic substitution failed. The automatic substitution registration was attempted because a call to jdk.internal.misc.Unsafe.objectFieldOffset(Class, String) was detected in the static initializer of jdk.internal.misc.InnocuousThread. Detailed failure reason(s): Could not determine the field where the value produced by the call to jdk.internal.misc.Unsafe.objectFieldOffset(Class, String) for the field offset computation is stored. The call is not directly followed by a field store or by a sign extend node followed directly by a field store.
    Warning: RecomputeFieldValue.FieldOffset automatic substitution failed. The automatic substitution registration was attempted because a call to jdk.internal.misc.Unsafe.objectFieldOffset(Class, String) was detected in the static initializer of jdk.internal.misc.InnocuousThread. Detailed failure reason(s): Could not determine the field where the value produced by the call to jdk.internal.misc.Unsafe.objectFieldOffset(Class, String) for the field offset computation is stored. The call is not directly followed by a field store or by a sign extend node followed directly by a field store.
    [hello:19205]   (typeflow):   6,324.79 ms
    [hello:19205]    (objects):   6,154.23 ms
    [hello:19205]   (features):     245.79 ms
    [hello:19205]     analysis:  12,930.88 ms
    [hello:19205]     universe:     318.56 ms
    [hello:19205]      (parse):     970.05 ms
    [hello:19205]     (inline):   1,849.87 ms
    [hello:19205]    (compile):   8,515.67 ms
    [hello:19205]      compile:  11,999.75 ms
    [hello:19205]        image:   1,248.74 ms
    [hello:19205]        write:     155.05 ms
    [hello:19205]      [total]:  30,392.57 ms

    [master $%=] ~/OLabs/git/svm-master/graal/substratevm> ./hello
    Hello Java 11.0.2

You can see that overall native-image works reasonably well for Java 11 already.

But there is still work to do.

E.g. currently when you build the "native-image" image on Java 11:

    [master $%=] ~/OLabs/git/svm-master/graal/substratevm> mkdir -p svmbuild/native-image-root-11/bin

    [master $%=] ~/OLabs/git/svm-master/graal/substratevm> mx native-image --tool:native-image -H:Path=svmbuild/native-image-root-11/bin
    [native-image:20223]    classlist:   1,238.58 ms
    ...
    [native-image:20223]        write:     224.72 ms
    [native-image:20223]      [total]:  40,393.15 ms

And you try to use it you get:

    [master $%=] ~/OLabs/git/svm-master/graal/substratevm> svmbuild/native-image-root-11/bin/native-image --tool:native-image -H:Path=svmbuild/native-image-root-11/bin
    Error: Starting image-build server instance failed
    Caused by: com.oracle.svm.driver.NativeImage$NativeImageError: Could not determine port for sending image-build requests.
    Server stdout/stderr:
    Exception in thread "main" com.oracle.svm.core.util.VMError$HostedError: Static field processReaperExecutor of class java.lang.UNIXProcess can't be reset. Underlying exception: java.lang.UNIXProcess

(Though, if you use that "native-image" image with --no-server it works
as expected)

If someone wants to work on Java 11 support while I'm busy with other things I suggest looking at the changes brought in by merge commit

    https://github.com/oracle/graal/commit/ed5f5f82d2962e5f65b3ee784a0cd62c489c41c5

and start improving on that.

HTH,
Paul