Removing BinaryOpIC::Clear. This method relied on some less-than-obvious hack...

src/ic.cc

 // Copyright 2006-2009 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 206 matching lines @@
 
   // Don't clear debug break inline cache as it will remove the break point.
   if (target->ic_state() == DEBUG_BREAK) return;
 
   switch (target->kind()) {
     case Code::LOAD_IC: return LoadIC::Clear(address, target);
     case Code::KEYED_LOAD_IC: return KeyedLoadIC::Clear(address, target);
     case Code::STORE_IC: return StoreIC::Clear(address, target);
     case Code::KEYED_STORE_IC: return KeyedStoreIC::Clear(address, target);
     case Code::CALL_IC: return CallIC::Clear(address, target);
-    case Code::BINARY_OP_IC: return BinaryOpIC::Clear(address, target);
+    case Code::BINARY_OP_IC: return;  // Clearing these is tricky and does not
+                                      // make any performance difference.
     default: UNREACHABLE();
   }
 }
 
 
 void CallIC::Clear(Address address, Code* target) {
   State state = target->ic_state();
   InLoopFlag in_loop = target->ic_in_loop();
   if (state == UNINITIALIZED) return;
   Code* code =
@@ skipping 1159 matching lines @@
   return ic.Store(state, args.at<Object>(0), args.at<Object>(1),
                   args.at<Object>(2));
 }
 
 
 void BinaryOpIC::patch(Code* code) {
   set_target(code);
 }
 
 
-void BinaryOpIC::Clear(Address address, Code* target) {
-  if (target->ic_state() == UNINITIALIZED) return;
-
-  // At the end of a fast case stub there should be a reference to
-  // a corresponding UNINITIALIZED stub, so look for the last reloc info item.
-  RelocInfo* rinfo = NULL;
-  for (RelocIterator it(target, RelocInfo::kCodeTargetMask);
-       !it.done(); it.next()) {
-    rinfo = it.rinfo();
-  }
-
-  ASSERT(rinfo != NULL);
-  Code* uninit_stub = Code::GetCodeFromTargetAddress(rinfo->target_address());
-  ASSERT(uninit_stub->ic_state() == UNINITIALIZED &&
-         uninit_stub->kind() == Code::BINARY_OP_IC);
-  SetTargetAtAddress(address, uninit_stub);
-}
-
-
 const char* BinaryOpIC::GetName(TypeInfo type_info) {
   switch (type_info) {
     case DEFAULT: return "Default";
     case GENERIC: return "Generic";
     case HEAP_NUMBERS: return "HeapNumbers";
     case STRINGS: return "Strings";
     default: return "Invalid";
   }
 }
 
@@ skipping 76 matching lines @@
 #undef ADDR
 };
 
 
 Address IC::AddressFromUtilityId(IC::UtilityId id) {
   return IC_utilities[id];
 }
 
 
 } }  // namespace v8::internal