Class LibGraal

java.lang.Object
com.oracle.truffle.runtime.hotspot.libgraal.LibGraal
public class LibGraal extends Object
Access to libgraal, a shared library containing an AOT compiled version of Graal produced by GraalVM Native Image. The libgraal library is only available if the HotSpot UseJVMCINativeLibrary flag is true and the current runtime includes the relevant JVMCI API additions for accessing libgraal. The isAvailable() method is provided to test these conditions. It must be used to guard usage of all other methods in this class. In addition, only the following methods can be called from within libgraal: The typical usage of this class is to link and call CEntryPoints in libgraal. Each call to a CEntryPoint requires an IsolateThread argument which can be obtained from a LibGraalScope.

  • Constructor Summary

    Constructors
    Constructor
    Description
    LibGraal()
     

  • Method Summary

    Modifier and Type
    Method
    Description
    static jdk.vm.ci.hotspot.HotSpotResolvedJavaType
    asResolvedJavaType(org.graalvm.word.PointerBase pointer)
     
    static boolean
    attachCurrentThread(boolean isDaemon, long[] isolate)
    Ensures the current thread is attached to the peer runtime.
    static boolean
    detachCurrentThread(boolean release)
    Detaches the current thread from the peer runtime.
    static long
    getFailedSpeculationsAddress(jdk.vm.ci.hotspot.HotSpotSpeculationLog log)
    Invokes the method getFailedSpeculationsAddress on a HotSpotSpeculationLog, if the method exists.
    static <T extends org.graalvm.word.PointerBase>
    T
    getJObjectValue(jdk.vm.ci.hotspot.HotSpotObjectConstant constant)
     
    static boolean
    isAvailable()
    Determines if libgraal is available for use.
    static boolean
    isSupported()
    Determines if the current runtime supports building a libgraal image.
    static void
    registerNativeMethods(Class<?> clazz)
    Links each native method in clazz to a CEntryPoint in libgraal.
    static long
    translate(Object obj)
    Creates or retrieves an object in the peer runtime that mirrors obj.
    static <T> T
    unhand(Class<T> type, long handle)
    Dereferences and returns the object referred to by the JNI global reference handle.

    Methods inherited from class Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

  • Constructor Details

    • LibGraal

      public LibGraal()

  • Method Details

    • isAvailable

      public static boolean isAvailable()
      Determines if libgraal is available for use.

    • isSupported

      public static boolean isSupported()
      Determines if the current runtime supports building a libgraal image.

    • registerNativeMethods

      public static void registerNativeMethods(Class<?> clazz)
      Links each native method in clazz to a CEntryPoint in libgraal.
      Throws:
      NullPointerException - if clazz == null
      UnsupportedOperationException - if libgraal is not enabled (i.e. -XX:-UseJVMCINativeLibrary)
      IllegalArgumentException - if clazz is Class.isPrimitive()
      IllegalStateException - if libgraal is unavailable
      UnsatisfiedLinkError - if there's a problem linking a native method in clazz (no matching JNI symbol or the native method is already linked to a different address)

    • translate

      public static long translate(Object obj)
      Creates or retrieves an object in the peer runtime that mirrors obj. This mechanism can be used to pass and return values between the HotSpot and libgraal runtimes. In the receiving runtime, the value can be converted back to an object with unhand.
      Parameters:
      obj - an object for which an equivalent instance in the peer runtime is requested
      Returns:
      a JNI global reference to the mirror of obj in the peer runtime
      Throws:
      IllegalArgumentException - if obj is not of a translatable type

    • unhand

      public static <T> T unhand(Class<T> type, long handle)
      Dereferences and returns the object referred to by the JNI global reference handle. The global reference is deleted prior to returning. Any further use of handle is invalid.
      Parameters:
      handle - a JNI global reference to an object in the current runtime
      Returns:
      the object referred to by handle
      Throws:
      ClassCastException - if the returned object cannot be cast to type

    • getJObjectValue

      public static <T extends org.graalvm.word.PointerBase> T getJObjectValue(jdk.vm.ci.hotspot.HotSpotObjectConstant constant)
      See Also:
      • HotSpotJVMCIRuntime.getJObjectValue(HotSpotObjectConstant)

    • asResolvedJavaType

      public static jdk.vm.ci.hotspot.HotSpotResolvedJavaType asResolvedJavaType(org.graalvm.word.PointerBase pointer)
      See Also:
      • HotSpotJVMCIRuntime.asResolvedJavaType(long)

    • attachCurrentThread

      public static boolean attachCurrentThread(boolean isDaemon, long[] isolate)
      Ensures the current thread is attached to the peer runtime.
      Parameters:
      isDaemon - if the thread is not yet attached, should it be attached as a daemon
      isolate - if non-null, the isolate for the current thread is returned in element 0
      Returns:
      true if this call attached the current thread, false if the current thread was already attached

    • detachCurrentThread

      public static boolean detachCurrentThread(boolean release)
      Detaches the current thread from the peer runtime.
      Parameters:
      release - if true and the VM supports releasing the JavaVM associated with libgraal runtimes and this is the last thread attached to a libgraal runtime, then this call destroys the associated JavaVM instance, releasing its resources
      Returns:
      true if the JavaVM associated with the libgraal runtime was destroyed as a result of this call

    • getFailedSpeculationsAddress

      public static long getFailedSpeculationsAddress(jdk.vm.ci.hotspot.HotSpotSpeculationLog log)
      Invokes the method getFailedSpeculationsAddress on a HotSpotSpeculationLog, if the method exists.
      Returns:
      the address of the pointer to the native failed speculations list.
      Throws:
      UnsupportedOperationException - if unsupported