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

rev 7978 : direct (fastpath) LambdaMetafactory invokation from callSite

*** 259,271 ****
                               String name, MethodType type,
                               // Extra arguments for BSM, if any:
                               Object info,
                               // Caller information:
                               Class<?> callerClass) {
!         Object caller = IMPL_LOOKUP.in(callerClass);
!         CallSite site;
          try {
              Object binding;
              info = maybeReBox(info);
              if (info == null) {
                  binding = bootstrapMethod.invoke(caller, name, type);
              } else if (!info.getClass().isArray()) {
--- 259,275 ----
                               String name, MethodType type,
                               // Extra arguments for BSM, if any:
                               Object info,
                               // Caller information:
                               Class<?> callerClass) {
!         MethodHandles.Lookup caller = IMPL_LOOKUP.in(callerClass);
          try {
+             CallSite site;
+             if(isLambdaMetafactory(bootstrapMethod, info)) { // LambdaMetafactory fastpath
+                 Object[] argv = (Object[]) info;
+                 site = LambdaMetafactory.metafactory(caller, name, type, (MethodType)argv[0], (MethodHandle)argv[1], (MethodType)argv[2]);
+             } else {
                  Object binding;
                  info = maybeReBox(info);
                  if (info == null) {
                      binding = bootstrapMethod.invoke(caller, name, type);
                  } else if (!info.getClass().isArray()) {
*** 280,306 ****
                      binding = bootstrapMethod.invoke(caller, name, type, argv);
                  else
                      binding = MethodHandles.spreadInvoker(bsmType, 3)
                          .invoke(bootstrapMethod, caller, name, type, argv);
              }
-             //System.out.println("BSM for "+name+type+" => "+binding);
              if (binding instanceof CallSite) {
                  site = (CallSite) binding;
              }  else {
                  throw new ClassCastException("bootstrap method failed to produce a CallSite");
              }
              if (!site.getTarget().type().equals(type))
                  throw new WrongMethodTypeException("wrong type: "+site.getTarget());
          } catch (Throwable ex) {
              BootstrapMethodError bex;
              if (ex instanceof BootstrapMethodError)
                  bex = (BootstrapMethodError) ex;
              else
                  bex = new BootstrapMethodError("call site initialization exception", ex);
              throw bex;
          }
!         return site;
      }
  
      private static Object maybeReBox(Object x) {
          if (x instanceof Integer) {
              int xi = (int) x;
--- 284,328 ----
                          binding = bootstrapMethod.invoke(caller, name, type, argv);
                      else
                          binding = MethodHandles.spreadInvoker(bsmType, 3)
                                  .invoke(bootstrapMethod, caller, name, type, argv);
                  }
                  if (binding instanceof CallSite) {
                      site = (CallSite) binding;
                  } else {
                      throw new ClassCastException("bootstrap method failed to produce a CallSite");
                  }
+             }
              if (!site.getTarget().type().equals(type))
                  throw new WrongMethodTypeException("wrong type: "+site.getTarget());
+             return site;
          } catch (Throwable ex) {
              BootstrapMethodError bex;
              if (ex instanceof BootstrapMethodError)
                  bex = (BootstrapMethodError) ex;
              else
                  bex = new BootstrapMethodError("call site initialization exception", ex);
              throw bex;
          }
! 
!     }
! 
!     private static boolean isLambdaMetafactory(MethodHandle mh, Object info) {
!         MemberName mn = mh.internalMemberName();
!         if ((mn != null) &&
!                 (mn.getDeclaringClass().equals(LambdaMetafactory.class)) &&
!                 (mn.getName().equals("metafactory")) &&
!                 (mn.getReferenceKind() == MethodHandleNatives.Constants.REF_invokeStatic) &&
!                 (info instanceof Object[])) {
!             Object[] argv = (Object[]) info;
!             // checks info inconsistency -> let's slowpath throws all exceptions
!             return (argv.length == 3) &&
!                     (argv[0] instanceof MethodType) &&
!                     (argv[1] instanceof MethodHandle) &&
!                     (argv[2] instanceof MethodType);
!         }
!         return false;
      }
  
      private static Object maybeReBox(Object x) {
          if (x instanceof Integer) {
              int xi = (int) x;