Java Code Examples for jdk.internal.dynalink.linker.GuardedInvocation#getGuard()

private static MethodHandle filterGuardReceiver(final GuardedInvocation link, final MethodHandle receiverFilter) {
    final MethodHandle test = link.getGuard();
    if (test == null) {
        return null;
    }

    final Class<?> receiverType = test.type().parameterType(0);
    final MethodHandle filter = MH.asType(receiverFilter,
            receiverFilter.type().changeParameterType(0, receiverType).
            changeReturnType(receiverType));

    return filterReceiver(test, filter);
}
 

private static MethodHandle filterGuardReceiver(final GuardedInvocation link, final MethodHandle receiverFilter) {
    final MethodHandle test = link.getGuard();
    if (test == null) {
        return null;
    }

    final Class<?> receiverType = test.type().parameterType(0);
    final MethodHandle filter = MH.asType(receiverFilter,
            receiverFilter.type().changeParameterType(0, receiverType).
            changeReturnType(receiverType));

    return filterReceiver(test, filter);
}
 

private static MethodHandle filterGuardReceiver(final GuardedInvocation link, final MethodHandle receiverFilter) {
    final MethodHandle test = link.getGuard();
    if (test == null) {
        return null;
    }

    final Class<?> receiverType = test.type().parameterType(0);
    final MethodHandle filter = MH.asType(receiverFilter,
            receiverFilter.type().changeParameterType(0, receiverType).
            changeReturnType(receiverType));

    return filterReceiver(test, filter);
}
 

private static MethodHandle filterGuardReceiver(final GuardedInvocation link, final MethodHandle receiverFilter) {
    final MethodHandle test = link.getGuard();
    if (test == null) {
        return null;
    }

    final Class<?> receiverType = test.type().parameterType(0);
    final MethodHandle filter = MH.asType(receiverFilter,
            receiverFilter.type().changeParameterType(0, receiverType).
            changeReturnType(receiverType));

    return filterReceiver(test, filter);
}
 

private static MethodHandle filterGuardReceiver(final GuardedInvocation link, final MethodHandle receiverFilter) {
    final MethodHandle test = link.getGuard();
    if (test == null) {
        return null;
    }

    final Class<?> receiverType = test.type().parameterType(0);
    final MethodHandle filter = MH.asType(receiverFilter,
            receiverFilter.type().changeParameterType(0, receiverType).
            changeReturnType(receiverType));

    return filterReceiver(test, filter);
}
 

private static MethodHandle filterGuardReceiver(final GuardedInvocation link, final MethodHandle receiverFilter) {
    final MethodHandle test = link.getGuard();
    if (test == null) {
        return null;
    }

    final Class<?> receiverType = test.type().parameterType(0);
    final MethodHandle filter = MH.asType(receiverFilter,
            receiverFilter.type().changeParameterType(0, receiverType).
            changeReturnType(receiverType));

    return filterReceiver(test, filter);
}
 

/**
 * Relinks a call site conforming to the invocation arguments.
 *
 * @param callSite the call site itself
 * @param arguments arguments to the invocation
 *
 * @return return the method handle for the invocation
 *
 * @throws Exception rethrows any exception thrown by the linkers
 */
@SuppressWarnings("unused")
private MethodHandle relink(final RelinkableCallSite callSite, final int relinkCount, final Object... arguments) throws Exception {
    final CallSiteDescriptor callSiteDescriptor = callSite.getDescriptor();
    final boolean unstableDetectionEnabled = unstableRelinkThreshold > 0;
    final boolean callSiteUnstable = unstableDetectionEnabled && relinkCount >= unstableRelinkThreshold;
    final LinkRequest linkRequest =
            runtimeContextArgCount == 0 ?
                    new LinkRequestImpl(callSiteDescriptor, callSite, relinkCount, callSiteUnstable, arguments) :
                    new RuntimeContextLinkRequestImpl(callSiteDescriptor, callSite, relinkCount, callSiteUnstable, arguments, runtimeContextArgCount);

    GuardedInvocation guardedInvocation = linkerServices.getGuardedInvocation(linkRequest);

    // None found - throw an exception
    if(guardedInvocation == null) {
        throw new NoSuchDynamicMethodException(callSiteDescriptor.toString());
    }

    // If our call sites have a runtime context, and the linker produced a context-stripped invocation, adapt the
    // produced invocation into contextual invocation (by dropping the context...)
    if(runtimeContextArgCount > 0) {
        final MethodType origType = callSiteDescriptor.getMethodType();
        final MethodHandle invocation = guardedInvocation.getInvocation();
        if(invocation.type().parameterCount() == origType.parameterCount() - runtimeContextArgCount) {
            final List<Class<?>> prefix = origType.parameterList().subList(1, runtimeContextArgCount + 1);
            final MethodHandle guard = guardedInvocation.getGuard();
            guardedInvocation = guardedInvocation.dropArguments(1, prefix);
        }
    }

    // Make sure we filter the invocation before linking it into the call site. This is typically used to match the
    // return type of the invocation to the call site.
    guardedInvocation = prelinkFilter.filter(guardedInvocation, linkRequest, linkerServices);
    Objects.requireNonNull(guardedInvocation);

    int newRelinkCount = relinkCount;
    // Note that the short-circuited "&&" evaluation below ensures we'll increment the relinkCount until
    // threshold + 1 but not beyond that. Threshold + 1 is treated as a special value to signal that resetAndRelink
    // has already executed once for the unstable call site; we only want the call site to throw away its current
    // linkage once, when it transitions to unstable.
    if(unstableDetectionEnabled && newRelinkCount <= unstableRelinkThreshold && newRelinkCount++ == unstableRelinkThreshold) {
        callSite.resetAndRelink(guardedInvocation, createRelinkAndInvokeMethod(callSite, newRelinkCount));
    } else {
        callSite.relink(guardedInvocation, createRelinkAndInvokeMethod(callSite, newRelinkCount));
    }
    if(syncOnRelink) {
        MutableCallSite.syncAll(new MutableCallSite[] { (MutableCallSite)callSite });
    }
    return guardedInvocation.getInvocation();
}
 

/**
 * Relinks a call site conforming to the invocation arguments.
 *
 * @param callSite the call site itself
 * @param arguments arguments to the invocation
 * @return return the method handle for the invocation
 * @throws Exception rethrows any exception thrown by the linkers
 */
@SuppressWarnings("unused")
private MethodHandle relink(RelinkableCallSite callSite, int relinkCount, Object... arguments) throws Exception {
    final CallSiteDescriptor callSiteDescriptor = callSite.getDescriptor();
    final boolean unstableDetectionEnabled = unstableRelinkThreshold > 0;
    final boolean callSiteUnstable = unstableDetectionEnabled && relinkCount >= unstableRelinkThreshold;
    final LinkRequest linkRequest =
            runtimeContextArgCount == 0 ? new LinkRequestImpl(callSiteDescriptor, callSiteUnstable, arguments)
                    : new RuntimeContextLinkRequestImpl(callSiteDescriptor, callSiteUnstable, arguments,
                            runtimeContextArgCount);

    // Find a suitable method handle with a guard
    GuardedInvocation guardedInvocation = linkerServices.getGuardedInvocation(linkRequest);

    // None found - throw an exception
    if(guardedInvocation == null) {
        throw new NoSuchDynamicMethodException(callSiteDescriptor.toString());
    }

    // If our call sites have a runtime context, and the linker produced a context-stripped invocation, adapt the
    // produced invocation into contextual invocation (by dropping the context...)
    if(runtimeContextArgCount > 0) {
        final MethodType origType = callSiteDescriptor.getMethodType();
        final MethodHandle invocation = guardedInvocation.getInvocation();
        if(invocation.type().parameterCount() == origType.parameterCount() - runtimeContextArgCount) {
            final List<Class<?>> prefix = origType.parameterList().subList(1, runtimeContextArgCount + 1);
            final MethodHandle guard = guardedInvocation.getGuard();
            guardedInvocation = guardedInvocation.dropArguments(1, prefix);
        }
    }

    int newRelinkCount = relinkCount;
    // Note that the short-circuited "&&" evaluation below ensures we'll increment the relinkCount until
    // threshold + 1 but not beyond that. Threshold + 1 is treated as a special value to signal that resetAndRelink
    // has already executed once for the unstable call site; we only want the call site to throw away its current
    // linkage once, when it transitions to unstable.
    if(unstableDetectionEnabled && newRelinkCount <= unstableRelinkThreshold && newRelinkCount++ == unstableRelinkThreshold) {
        callSite.resetAndRelink(guardedInvocation, createRelinkAndInvokeMethod(callSite, newRelinkCount));
    } else {
        callSite.relink(guardedInvocation, createRelinkAndInvokeMethod(callSite, newRelinkCount));
    }
    if(syncOnRelink) {
        MutableCallSite.syncAll(new MutableCallSite[] { (MutableCallSite)callSite });
    }
    return guardedInvocation.getInvocation();
}
 

private static MethodHandle filterGuard(final GuardedInvocation link, final MethodHandle filter) {
    final MethodHandle test = link.getGuard();
    return test == null ? null : filter(test, filter);
}
 

/**
 * Relinks a call site conforming to the invocation arguments.
 *
 * @param callSite the call site itself
 * @param arguments arguments to the invocation
 *
 * @return return the method handle for the invocation
 *
 * @throws Exception rethrows any exception thrown by the linkers
 */
@SuppressWarnings("unused")
private MethodHandle relink(final RelinkableCallSite callSite, final int relinkCount, final Object... arguments) throws Exception {
    final CallSiteDescriptor callSiteDescriptor = callSite.getDescriptor();
    final boolean unstableDetectionEnabled = unstableRelinkThreshold > 0;
    final boolean callSiteUnstable = unstableDetectionEnabled && relinkCount >= unstableRelinkThreshold;
    final LinkRequest linkRequest =
            runtimeContextArgCount == 0 ?
                    new LinkRequestImpl(callSiteDescriptor, callSite, relinkCount, callSiteUnstable, arguments) :
                    new RuntimeContextLinkRequestImpl(callSiteDescriptor, callSite, relinkCount, callSiteUnstable, arguments, runtimeContextArgCount);

    GuardedInvocation guardedInvocation = linkerServices.getGuardedInvocation(linkRequest);

    // None found - throw an exception
    if(guardedInvocation == null) {
        throw new NoSuchDynamicMethodException(callSiteDescriptor.toString());
    }

    // If our call sites have a runtime context, and the linker produced a context-stripped invocation, adapt the
    // produced invocation into contextual invocation (by dropping the context...)
    if(runtimeContextArgCount > 0) {
        final MethodType origType = callSiteDescriptor.getMethodType();
        final MethodHandle invocation = guardedInvocation.getInvocation();
        if(invocation.type().parameterCount() == origType.parameterCount() - runtimeContextArgCount) {
            final List<Class<?>> prefix = origType.parameterList().subList(1, runtimeContextArgCount + 1);
            final MethodHandle guard = guardedInvocation.getGuard();
            guardedInvocation = guardedInvocation.dropArguments(1, prefix);
        }
    }

    // Make sure we filter the invocation before linking it into the call site. This is typically used to match the
    // return type of the invocation to the call site.
    guardedInvocation = prelinkFilter.filter(guardedInvocation, linkRequest, linkerServices);
    Objects.requireNonNull(guardedInvocation);

    int newRelinkCount = relinkCount;
    // Note that the short-circuited "&&" evaluation below ensures we'll increment the relinkCount until
    // threshold + 1 but not beyond that. Threshold + 1 is treated as a special value to signal that resetAndRelink
    // has already executed once for the unstable call site; we only want the call site to throw away its current
    // linkage once, when it transitions to unstable.
    if(unstableDetectionEnabled && newRelinkCount <= unstableRelinkThreshold && newRelinkCount++ == unstableRelinkThreshold) {
        callSite.resetAndRelink(guardedInvocation, createRelinkAndInvokeMethod(callSite, newRelinkCount));
    } else {
        callSite.relink(guardedInvocation, createRelinkAndInvokeMethod(callSite, newRelinkCount));
    }
    if(syncOnRelink) {
        MutableCallSite.syncAll(new MutableCallSite[] { (MutableCallSite)callSite });
    }
    return guardedInvocation.getInvocation();
}
 

/**
 * Relinks a call site conforming to the invocation arguments.
 *
 * @param callSite the call site itself
 * @param arguments arguments to the invocation
 * @return return the method handle for the invocation
 * @throws Exception rethrows any exception thrown by the linkers
 */
@SuppressWarnings("unused")
private MethodHandle relink(RelinkableCallSite callSite, int relinkCount, Object... arguments) throws Exception {
    final CallSiteDescriptor callSiteDescriptor = callSite.getDescriptor();
    final boolean unstableDetectionEnabled = unstableRelinkThreshold > 0;
    final boolean callSiteUnstable = unstableDetectionEnabled && relinkCount >= unstableRelinkThreshold;
    final LinkRequest linkRequest =
            runtimeContextArgCount == 0 ? new LinkRequestImpl(callSiteDescriptor, callSiteUnstable, arguments)
                    : new RuntimeContextLinkRequestImpl(callSiteDescriptor, callSiteUnstable, arguments,
                            runtimeContextArgCount);

    // Find a suitable method handle with a guard
    GuardedInvocation guardedInvocation = linkerServices.getGuardedInvocation(linkRequest);

    // None found - throw an exception
    if(guardedInvocation == null) {
        throw new NoSuchDynamicMethodException(callSiteDescriptor.toString());
    }

    // If our call sites have a runtime context, and the linker produced a context-stripped invocation, adapt the
    // produced invocation into contextual invocation (by dropping the context...)
    if(runtimeContextArgCount > 0) {
        final MethodType origType = callSiteDescriptor.getMethodType();
        final MethodHandle invocation = guardedInvocation.getInvocation();
        if(invocation.type().parameterCount() == origType.parameterCount() - runtimeContextArgCount) {
            final List<Class<?>> prefix = origType.parameterList().subList(1, runtimeContextArgCount + 1);
            final MethodHandle guard = guardedInvocation.getGuard();
            guardedInvocation = guardedInvocation.dropArguments(1, prefix);
        }
    }

    int newRelinkCount = relinkCount;
    // Note that the short-circuited "&&" evaluation below ensures we'll increment the relinkCount until
    // threshold + 1 but not beyond that. Threshold + 1 is treated as a special value to signal that resetAndRelink
    // has already executed once for the unstable call site; we only want the call site to throw away its current
    // linkage once, when it transitions to unstable.
    if(unstableDetectionEnabled && newRelinkCount <= unstableRelinkThreshold && newRelinkCount++ == unstableRelinkThreshold) {
        callSite.resetAndRelink(guardedInvocation, createRelinkAndInvokeMethod(callSite, newRelinkCount));
    } else {
        callSite.relink(guardedInvocation, createRelinkAndInvokeMethod(callSite, newRelinkCount));
    }
    if(syncOnRelink) {
        MutableCallSite.syncAll(new MutableCallSite[] { (MutableCallSite)callSite });
    }
    return guardedInvocation.getInvocation();
}
 

private static MethodHandle filterGuard(final GuardedInvocation link, final MethodHandle filter) {
    final MethodHandle test = link.getGuard();
    return test == null ? null : filter(test, filter);
}
 

/**
 * Relinks a call site conforming to the invocation arguments.
 *
 * @param callSite the call site itself
 * @param arguments arguments to the invocation
 * @return return the method handle for the invocation
 * @throws Exception rethrows any exception thrown by the linkers
 */
@SuppressWarnings("unused")
private MethodHandle relink(RelinkableCallSite callSite, int relinkCount, Object... arguments) throws Exception {
    final CallSiteDescriptor callSiteDescriptor = callSite.getDescriptor();
    final boolean unstableDetectionEnabled = unstableRelinkThreshold > 0;
    final boolean callSiteUnstable = unstableDetectionEnabled && relinkCount >= unstableRelinkThreshold;
    final LinkRequest linkRequest =
            runtimeContextArgCount == 0 ? new LinkRequestImpl(callSiteDescriptor, callSiteUnstable, arguments)
                    : new RuntimeContextLinkRequestImpl(callSiteDescriptor, callSiteUnstable, arguments,
                            runtimeContextArgCount);

    // Find a suitable method handle with a guard
    GuardedInvocation guardedInvocation = linkerServices.getGuardedInvocation(linkRequest);

    // None found - throw an exception
    if(guardedInvocation == null) {
        throw new NoSuchDynamicMethodException(callSiteDescriptor.toString());
    }

    // If our call sites have a runtime context, and the linker produced a context-stripped invocation, adapt the
    // produced invocation into contextual invocation (by dropping the context...)
    if(runtimeContextArgCount > 0) {
        final MethodType origType = callSiteDescriptor.getMethodType();
        final MethodHandle invocation = guardedInvocation.getInvocation();
        if(invocation.type().parameterCount() == origType.parameterCount() - runtimeContextArgCount) {
            final List<Class<?>> prefix = origType.parameterList().subList(1, runtimeContextArgCount + 1);
            final MethodHandle guard = guardedInvocation.getGuard();
            guardedInvocation = guardedInvocation.dropArguments(1, prefix);
        }
    }

    int newRelinkCount = relinkCount;
    // Note that the short-circuited "&&" evaluation below ensures we'll increment the relinkCount until
    // threshold + 1 but not beyond that. Threshold + 1 is treated as a special value to signal that resetAndRelink
    // has already executed once for the unstable call site; we only want the call site to throw away its current
    // linkage once, when it transitions to unstable.
    if(unstableDetectionEnabled && newRelinkCount <= unstableRelinkThreshold && newRelinkCount++ == unstableRelinkThreshold) {
        callSite.resetAndRelink(guardedInvocation, createRelinkAndInvokeMethod(callSite, newRelinkCount));
    } else {
        callSite.relink(guardedInvocation, createRelinkAndInvokeMethod(callSite, newRelinkCount));
    }
    if(syncOnRelink) {
        MutableCallSite.syncAll(new MutableCallSite[] { (MutableCallSite)callSite });
    }
    return guardedInvocation.getInvocation();
}
 

private static MethodHandle filterGuard(final GuardedInvocation link, final MethodHandle filter) {
    final MethodHandle test = link.getGuard();
    return test == null ? null : filter(test, filter);
}
 

/**
 * Relinks a call site conforming to the invocation arguments.
 *
 * @param callSite the call site itself
 * @param arguments arguments to the invocation
 *
 * @return return the method handle for the invocation
 *
 * @throws Exception rethrows any exception thrown by the linkers
 */
@SuppressWarnings("unused")
private MethodHandle relink(final RelinkableCallSite callSite, final int relinkCount, final Object... arguments) throws Exception {
    final CallSiteDescriptor callSiteDescriptor = callSite.getDescriptor();
    final boolean unstableDetectionEnabled = unstableRelinkThreshold > 0;
    final boolean callSiteUnstable = unstableDetectionEnabled && relinkCount >= unstableRelinkThreshold;
    final LinkRequest linkRequest =
            runtimeContextArgCount == 0 ?
                    new LinkRequestImpl(callSiteDescriptor, callSite, relinkCount, callSiteUnstable, arguments) :
                    new RuntimeContextLinkRequestImpl(callSiteDescriptor, callSite, relinkCount, callSiteUnstable, arguments, runtimeContextArgCount);

    GuardedInvocation guardedInvocation = linkerServices.getGuardedInvocation(linkRequest);

    // None found - throw an exception
    if(guardedInvocation == null) {
        throw new NoSuchDynamicMethodException(callSiteDescriptor.toString());
    }

    // If our call sites have a runtime context, and the linker produced a context-stripped invocation, adapt the
    // produced invocation into contextual invocation (by dropping the context...)
    if(runtimeContextArgCount > 0) {
        final MethodType origType = callSiteDescriptor.getMethodType();
        final MethodHandle invocation = guardedInvocation.getInvocation();
        if(invocation.type().parameterCount() == origType.parameterCount() - runtimeContextArgCount) {
            final List<Class<?>> prefix = origType.parameterList().subList(1, runtimeContextArgCount + 1);
            final MethodHandle guard = guardedInvocation.getGuard();
            guardedInvocation = guardedInvocation.dropArguments(1, prefix);
        }
    }

    // Make sure we filter the invocation before linking it into the call site. This is typically used to match the
    // return type of the invocation to the call site.
    guardedInvocation = prelinkFilter.filter(guardedInvocation, linkRequest, linkerServices);
    Objects.requireNonNull(guardedInvocation);

    int newRelinkCount = relinkCount;
    // Note that the short-circuited "&&" evaluation below ensures we'll increment the relinkCount until
    // threshold + 1 but not beyond that. Threshold + 1 is treated as a special value to signal that resetAndRelink
    // has already executed once for the unstable call site; we only want the call site to throw away its current
    // linkage once, when it transitions to unstable.
    if(unstableDetectionEnabled && newRelinkCount <= unstableRelinkThreshold && newRelinkCount++ == unstableRelinkThreshold) {
        callSite.resetAndRelink(guardedInvocation, createRelinkAndInvokeMethod(callSite, newRelinkCount));
    } else {
        callSite.relink(guardedInvocation, createRelinkAndInvokeMethod(callSite, newRelinkCount));
    }
    if(syncOnRelink) {
        MutableCallSite.syncAll(new MutableCallSite[] { (MutableCallSite)callSite });
    }
    return guardedInvocation.getInvocation();
}
 

/**
 * Relinks a call site conforming to the invocation arguments.
 *
 * @param callSite the call site itself
 * @param arguments arguments to the invocation
 *
 * @return return the method handle for the invocation
 *
 * @throws Exception rethrows any exception thrown by the linkers
 */
@SuppressWarnings("unused")
private MethodHandle relink(final RelinkableCallSite callSite, final int relinkCount, final Object... arguments) throws Exception {
    final CallSiteDescriptor callSiteDescriptor = callSite.getDescriptor();
    final boolean unstableDetectionEnabled = unstableRelinkThreshold > 0;
    final boolean callSiteUnstable = unstableDetectionEnabled && relinkCount >= unstableRelinkThreshold;
    final LinkRequest linkRequest =
            runtimeContextArgCount == 0 ?
                    new LinkRequestImpl(callSiteDescriptor, callSite, relinkCount, callSiteUnstable, arguments) :
                    new RuntimeContextLinkRequestImpl(callSiteDescriptor, callSite, relinkCount, callSiteUnstable, arguments, runtimeContextArgCount);

    GuardedInvocation guardedInvocation = linkerServices.getGuardedInvocation(linkRequest);

    // None found - throw an exception
    if(guardedInvocation == null) {
        throw new NoSuchDynamicMethodException(callSiteDescriptor.toString());
    }

    // If our call sites have a runtime context, and the linker produced a context-stripped invocation, adapt the
    // produced invocation into contextual invocation (by dropping the context...)
    if(runtimeContextArgCount > 0) {
        final MethodType origType = callSiteDescriptor.getMethodType();
        final MethodHandle invocation = guardedInvocation.getInvocation();
        if(invocation.type().parameterCount() == origType.parameterCount() - runtimeContextArgCount) {
            final List<Class<?>> prefix = origType.parameterList().subList(1, runtimeContextArgCount + 1);
            final MethodHandle guard = guardedInvocation.getGuard();
            guardedInvocation = guardedInvocation.dropArguments(1, prefix);
        }
    }

    // Make sure we filter the invocation before linking it into the call site. This is typically used to match the
    // return type of the invocation to the call site.
    guardedInvocation = prelinkFilter.filter(guardedInvocation, linkRequest, linkerServices);
    Objects.requireNonNull(guardedInvocation);

    int newRelinkCount = relinkCount;
    // Note that the short-circuited "&&" evaluation below ensures we'll increment the relinkCount until
    // threshold + 1 but not beyond that. Threshold + 1 is treated as a special value to signal that resetAndRelink
    // has already executed once for the unstable call site; we only want the call site to throw away its current
    // linkage once, when it transitions to unstable.
    if(unstableDetectionEnabled && newRelinkCount <= unstableRelinkThreshold && newRelinkCount++ == unstableRelinkThreshold) {
        callSite.resetAndRelink(guardedInvocation, createRelinkAndInvokeMethod(callSite, newRelinkCount));
    } else {
        callSite.relink(guardedInvocation, createRelinkAndInvokeMethod(callSite, newRelinkCount));
    }
    if(syncOnRelink) {
        MutableCallSite.syncAll(new MutableCallSite[] { (MutableCallSite)callSite });
    }
    return guardedInvocation.getInvocation();
}
 

/**
 * Relinks a call site conforming to the invocation arguments.
 *
 * @param callSite the call site itself
 * @param arguments arguments to the invocation
 *
 * @return return the method handle for the invocation
 *
 * @throws Exception rethrows any exception thrown by the linkers
 */
@SuppressWarnings("unused")
private MethodHandle relink(final RelinkableCallSite callSite, final int relinkCount, final Object... arguments) throws Exception {
    final CallSiteDescriptor callSiteDescriptor = callSite.getDescriptor();
    final boolean unstableDetectionEnabled = unstableRelinkThreshold > 0;
    final boolean callSiteUnstable = unstableDetectionEnabled && relinkCount >= unstableRelinkThreshold;
    final LinkRequest linkRequest =
            runtimeContextArgCount == 0 ?
                    new LinkRequestImpl(callSiteDescriptor, callSite, relinkCount, callSiteUnstable, arguments) :
                    new RuntimeContextLinkRequestImpl(callSiteDescriptor, callSite, relinkCount, callSiteUnstable, arguments, runtimeContextArgCount);

    GuardedInvocation guardedInvocation = linkerServices.getGuardedInvocation(linkRequest);

    // None found - throw an exception
    if(guardedInvocation == null) {
        throw new NoSuchDynamicMethodException(callSiteDescriptor.toString());
    }

    // If our call sites have a runtime context, and the linker produced a context-stripped invocation, adapt the
    // produced invocation into contextual invocation (by dropping the context...)
    if(runtimeContextArgCount > 0) {
        final MethodType origType = callSiteDescriptor.getMethodType();
        final MethodHandle invocation = guardedInvocation.getInvocation();
        if(invocation.type().parameterCount() == origType.parameterCount() - runtimeContextArgCount) {
            final List<Class<?>> prefix = origType.parameterList().subList(1, runtimeContextArgCount + 1);
            final MethodHandle guard = guardedInvocation.getGuard();
            guardedInvocation = guardedInvocation.dropArguments(1, prefix);
        }
    }

    // Make sure we filter the invocation before linking it into the call site. This is typically used to match the
    // return type of the invocation to the call site.
    guardedInvocation = prelinkFilter.filter(guardedInvocation, linkRequest, linkerServices);
    Objects.requireNonNull(guardedInvocation);

    int newRelinkCount = relinkCount;
    // Note that the short-circuited "&&" evaluation below ensures we'll increment the relinkCount until
    // threshold + 1 but not beyond that. Threshold + 1 is treated as a special value to signal that resetAndRelink
    // has already executed once for the unstable call site; we only want the call site to throw away its current
    // linkage once, when it transitions to unstable.
    if(unstableDetectionEnabled && newRelinkCount <= unstableRelinkThreshold && newRelinkCount++ == unstableRelinkThreshold) {
        callSite.resetAndRelink(guardedInvocation, createRelinkAndInvokeMethod(callSite, newRelinkCount));
    } else {
        callSite.relink(guardedInvocation, createRelinkAndInvokeMethod(callSite, newRelinkCount));
    }
    if(syncOnRelink) {
        MutableCallSite.syncAll(new MutableCallSite[] { (MutableCallSite)callSite });
    }
    return guardedInvocation.getInvocation();
}
 

/**
 * Relinks a call site conforming to the invocation arguments.
 *
 * @param callSite the call site itself
 * @param arguments arguments to the invocation
 *
 * @return return the method handle for the invocation
 *
 * @throws Exception rethrows any exception thrown by the linkers
 */
@SuppressWarnings("unused")
private MethodHandle relink(final RelinkableCallSite callSite, final int relinkCount, final Object... arguments) throws Exception {
    final CallSiteDescriptor callSiteDescriptor = callSite.getDescriptor();
    final boolean unstableDetectionEnabled = unstableRelinkThreshold > 0;
    final boolean callSiteUnstable = unstableDetectionEnabled && relinkCount >= unstableRelinkThreshold;
    final LinkRequest linkRequest =
            runtimeContextArgCount == 0 ?
                    new LinkRequestImpl(callSiteDescriptor, callSite, relinkCount, callSiteUnstable, arguments) :
                    new RuntimeContextLinkRequestImpl(callSiteDescriptor, callSite, relinkCount, callSiteUnstable, arguments, runtimeContextArgCount);

    GuardedInvocation guardedInvocation = linkerServices.getGuardedInvocation(linkRequest);

    // None found - throw an exception
    if(guardedInvocation == null) {
        throw new NoSuchDynamicMethodException(callSiteDescriptor.toString());
    }

    // If our call sites have a runtime context, and the linker produced a context-stripped invocation, adapt the
    // produced invocation into contextual invocation (by dropping the context...)
    if(runtimeContextArgCount > 0) {
        final MethodType origType = callSiteDescriptor.getMethodType();
        final MethodHandle invocation = guardedInvocation.getInvocation();
        if(invocation.type().parameterCount() == origType.parameterCount() - runtimeContextArgCount) {
            final List<Class<?>> prefix = origType.parameterList().subList(1, runtimeContextArgCount + 1);
            final MethodHandle guard = guardedInvocation.getGuard();
            guardedInvocation = guardedInvocation.dropArguments(1, prefix);
        }
    }

    // Make sure we filter the invocation before linking it into the call site. This is typically used to match the
    // return type of the invocation to the call site.
    guardedInvocation = prelinkFilter.filter(guardedInvocation, linkRequest, linkerServices);
    Objects.requireNonNull(guardedInvocation);

    int newRelinkCount = relinkCount;
    // Note that the short-circuited "&&" evaluation below ensures we'll increment the relinkCount until
    // threshold + 1 but not beyond that. Threshold + 1 is treated as a special value to signal that resetAndRelink
    // has already executed once for the unstable call site; we only want the call site to throw away its current
    // linkage once, when it transitions to unstable.
    if(unstableDetectionEnabled && newRelinkCount <= unstableRelinkThreshold && newRelinkCount++ == unstableRelinkThreshold) {
        callSite.resetAndRelink(guardedInvocation, createRelinkAndInvokeMethod(callSite, newRelinkCount));
    } else {
        callSite.relink(guardedInvocation, createRelinkAndInvokeMethod(callSite, newRelinkCount));
    }
    if(syncOnRelink) {
        MutableCallSite.syncAll(new MutableCallSite[] { (MutableCallSite)callSite });
    }
    return guardedInvocation.getInvocation();
}