Serendipitously arrange the tags so that String.length() becomes a branch-fre...

src/ic.cc

 // Copyright 2006-2008 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 441 matching lines @@
     return TypeError("non_object_property_load", object, name);
   }
 
   if (FLAG_use_ic) {
     // Use specialized code for getting the length of strings.
     if (object->IsString() && name->Equals(Heap::length_symbol())) {
 #ifdef DEBUG
       if (FLAG_trace_ic) PrintF("[LoadIC : +#length /string]\n");
 #endif
       Code* target = NULL;
-      if (object->IsShortString()) {
-        target = Builtins::builtin(Builtins::LoadIC_ShortStringLength);
-      } else if (object->IsMediumString()) {
-        target = Builtins::builtin(Builtins::LoadIC_MediumStringLength);
-      } else {
-        ASSERT(object->IsLongString());
-        target  = Builtins::builtin(Builtins::LoadIC_LongStringLength);
-      }
+      target = Builtins::builtin(Builtins::LoadIC_StringLength);
       set_target(target);
       StubCache::Set(*name, HeapObject::cast(*object)->map(), target);
       return Smi::FromInt(String::cast(*object)->length());
     }
 
     // Use specialized code for getting the length of arrays.
     if (object->IsJSArray() && name->Equals(Heap::length_symbol())) {
 #ifdef DEBUG
       if (FLAG_trace_ic) PrintF("[LoadIC : +#length /array]\n");
 #endif
@@ skipping 150 matching lines @@
     // of its properties; throw a TypeError in that case.
     if (object->IsUndefined() || object->IsNull()) {
       return TypeError("non_object_property_load", object, name);
     }
 
     if (FLAG_use_ic) {
       // Use specialized code for getting the length of strings.
       if (object->IsString() && name->Equals(Heap::length_symbol())) {
         Handle<String> string = Handle<String>::cast(object);
         Object* code = NULL;
-        if (string->IsShortString()) {
-          code = StubCache::ComputeKeyedLoadShortStringLength(*name, *string);
-        } else if (string->IsMediumString()) {
-          code =
-              StubCache::ComputeKeyedLoadMediumStringLength(*name, *string);
-        } else {
-          ASSERT(string->IsLongString());
-          code = StubCache::ComputeKeyedLoadLongStringLength(*name, *string);
-        }
+        code = StubCache::ComputeKeyedLoadStringLength(*name, *string);
         if (code->IsFailure()) return code;
         set_target(Code::cast(code));
 #ifdef DEBUG
         TraceIC("KeyedLoadIC", name, state, target());
 #endif
         return Smi::FromInt(string->length());
       }
 
       // Use specialized code for getting the length of arrays.
       if (object->IsJSArray() && name->Equals(Heap::length_symbol())) {
@@ skipping 533 matching lines @@
 #undef ADDR
 };
 
 
 Address IC::AddressFromUtilityId(IC::UtilityId id) {
   return IC_utilities[id];
 }
 
 
 } }  // namespace v8::internal