RFR: 8164044: Generate corresponding simple DelegatingMethodHandles when generating a DirectMethodHandle

[Aleksey Shipilev]

On 08/18/2016 12:33 AM, Claes Redestad wrote:
> Hi,
> 
> please review this change which adds pre-generation of simple
> DelegatingMethodHandles corresponding to the DirectMethodHandles we
> already pre-generate during linking.
> 
> webrev: http://cr.openjdk.java.net/~redestad/8164044/webrev.02/

*) This block:

  if (!dedupSet.contains(methodTypes[i])) {
     // do stuff
     dedupSet.add(methodTypes[i]);
  }

Is replaceable by:

  if (dedupSet.add(methodTypes[i])) {
     // do stuff
  }

*) Can save instantiation here, by moving ptypes into else branch:

 333         Class<?>[] ptypes = new Class<?>[parameters.length()];
 334         if (ptypes.length == 0) {
 335             return MethodType.methodType(rtype);
 336         } else {
 337             for (int i = 0; i < ptypes.length; i++) {
 338                 ptypes[i] = simpleType(parameters.charAt(i));
 339             }
 340             return MethodType.methodType(rtype, ptypes);
 341         }
 342     }

*) Many whitespaces from this switch:

195         switch (which) {
 196         case LF_INVVIRTUAL:    linkerName = "linkToVirtual";   kind
= DIRECT_INVOKE_VIRTUAL;     break;
 197         case LF_INVSTATIC:     linkerName = "linkToStatic";    kind
= DIRECT_INVOKE_STATIC;      break;
 198         case LF_INVSTATIC_INIT:linkerName = "linkToStatic";    kind
= DIRECT_INVOKE_STATIC_INIT; break;
 199         case LF_INVSPECIAL:    linkerName = "linkToSpecial";   kind
= DIRECT_INVOKE_SPECIAL;     break;
 200         case LF_INVINTERFACE:  linkerName = "linkToInterface"; kind
= DIRECT_INVOKE_INTERFACE;   break;
 201         case LF_NEWINVSPECIAL: linkerName = "linkToSpecial";   kind
= DIRECT_NEW_INVOKE_SPECIAL; break;
 202         default:  throw new InternalError("which="+which);

...ran away to this one:

 154     private static Kind whichKind(int whichCache) {
 155         switch(whichCache) {
 156             case MethodTypeForm.LF_REBIND:            return
BOUND_REINVOKER;
 157             case MethodTypeForm.LF_DELEGATE:          return DELEGATE;
 158             default:                                  return REINVOKER;
 159         }
 160     }

Thanks,
-Aleksey