src/share/classes/java/lang/invoke/CallSite.java

rev 10274 : 8050052: Small cleanups in java.lang.invoke code
Reviewed-by: ?
rev 10275 : imported patch invokers

*** 100,110 ****
       * via a call to {@link CallSite#setTarget(MethodHandle) setTarget}.
       * @throws NullPointerException if the proposed type is null
       */
      /*package-private*/
      CallSite(MethodType type) {
!         target = type.invokers().uninitializedCallSite();
      }
  
      /**
       * Make a call site object equipped with an initial target method handle.
       * @param target the method handle which will be the initial target of the call site
--- 100,110 ----
       * via a call to {@link CallSite#setTarget(MethodHandle) setTarget}.
       * @throws NullPointerException if the proposed type is null
       */
      /*package-private*/
      CallSite(MethodType type) {
!         target = makeUninitializedCallSite(type);
      }
  
      /**
       * Make a call site object equipped with an initial target method handle.
       * @param target the method handle which will be the initial target of the call site
*** 215,239 ****
          MethodHandle invoker = MethodHandles.exactInvoker(this.type());
          return MethodHandles.foldArguments(invoker, getTarget);
      }
  
      private static final MethodHandle GET_TARGET;
      static {
          try {
              GET_TARGET = IMPL_LOOKUP.
                  findVirtual(CallSite.class, "getTarget", MethodType.methodType(MethodHandle.class));
          } catch (ReflectiveOperationException e) {
              throw newInternalError(e);
          }
      }
  
      /** This guy is rolled into the default target if a MethodType is supplied to the constructor. */
!     /*package-private*/
!     static Empty uninitializedCallSite() {
          throw new IllegalStateException("uninitialized call site");
      }
  
      // unsafe stuff:
      private static final long TARGET_OFFSET;
      static {
          try {
              TARGET_OFFSET = UNSAFE.objectFieldOffset(CallSite.class.getDeclaredField("target"));
--- 215,252 ----
          MethodHandle invoker = MethodHandles.exactInvoker(this.type());
          return MethodHandles.foldArguments(invoker, getTarget);
      }
  
      private static final MethodHandle GET_TARGET;
+     private static final MethodHandle THROW_UCS;
      static {
          try {
              GET_TARGET = IMPL_LOOKUP.
                  findVirtual(CallSite.class, "getTarget", MethodType.methodType(MethodHandle.class));
+             THROW_UCS = IMPL_LOOKUP.
+                 findStatic(CallSite.class, "uninitializedCallSite", MethodType.methodType(Object.class, Object[].class));
          } catch (ReflectiveOperationException e) {
              throw newInternalError(e);
          }
      }
  
      /** This guy is rolled into the default target if a MethodType is supplied to the constructor. */
!     private static Object uninitializedCallSite(Object... ignore) {
          throw new IllegalStateException("uninitialized call site");
      }
  
+     private MethodHandle makeUninitializedCallSite(MethodType targetType) {
+         MethodType basicType = targetType.basicType();
+         MethodHandle invoker = basicType.form().cachedMethodHandle(MethodTypeForm.MH_UNINIT_CS);
+         if (invoker == null) {
+             invoker = THROW_UCS.asType(basicType);
+             invoker = basicType.form().setCachedMethodHandle(MethodTypeForm.MH_UNINIT_CS, invoker);
+         }
+         // unchecked view is OK since no values will be received or returned
+         return invoker.viewAsType(targetType);
+     }
+ 
      // unsafe stuff:
      private static final long TARGET_OFFSET;
      static {
          try {
              TARGET_OFFSET = UNSAFE.objectFieldOffset(CallSite.class.getDeclaredField("target"));