Optimize the equality check case of ICCompare stubs.

src/type-info.cc

 // Copyright 2011 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 241 matching lines @@
       // Uninitialized means never executed.
       return TypeInfo::Uninitialized();
     case CompareIC::SMIS:
       return TypeInfo::Smi();
     case CompareIC::HEAP_NUMBERS:
       return TypeInfo::Number();
     case CompareIC::SYMBOLS:
     case CompareIC::STRINGS:
       return TypeInfo::String();
     case CompareIC::OBJECTS:
+    case CompareIC::KNOWN_OBJECTS:
       // TODO(kasperl): We really need a type for JS objects here.
       return TypeInfo::NonPrimitive();
     case CompareIC::GENERIC:
     default:
       return unknown;
   }
 }
 
 
 bool TypeFeedbackOracle::IsSymbolCompare(CompareOperation* expr) {
   Handle<Object> object = GetInfo(expr->id());
   if (!object->IsCode()) return false;
   Handle<Code> code = Handle<Code>::cast(object);
   if (!code->is_compare_ic_stub()) return false;
   CompareIC::State state = static_cast<CompareIC::State>(code->compare_state());
   return state == CompareIC::SYMBOLS;
 }
 
 
+Handle<Map> TypeFeedbackOracle::GetCompareMap(CompareOperation* expr) {
+  Handle<Object> object = GetInfo(expr->id());
+  if (!object->IsCode()) return Handle<Map>::null();
+  Handle<Code> code = Handle<Code>::cast(object);
+  if (!code->is_compare_ic_stub()) return Handle<Map>::null();
+  CompareIC::State state = static_cast<CompareIC::State>(code->compare_state());
+  if (state != CompareIC::KNOWN_OBJECTS) {
+    return Handle<Map>::null();
+  }
+  return Handle<Map>(code->FindFirstMap());
+}
+
+
 TypeInfo TypeFeedbackOracle::UnaryType(UnaryOperation* expr) {
   Handle<Object> object = GetInfo(expr->id());
   TypeInfo unknown = TypeInfo::Unknown();
   if (!object->IsCode()) return unknown;
   Handle<Code> code = Handle<Code>::cast(object);
   ASSERT(code->is_unary_op_stub());
   UnaryOpIC::TypeInfo type = static_cast<UnaryOpIC::TypeInfo>(
       code->unary_op_type());
   switch (type) {
     case UnaryOpIC::SMI:
@@ skipping 65 matching lines @@
   switch (state) {
     case CompareIC::UNINITIALIZED:
       // Uninitialized means never executed.
       // TODO(fschneider): Introduce a separate value for never-executed ICs.
       return unknown;
     case CompareIC::SMIS:
       return TypeInfo::Smi();
     case CompareIC::HEAP_NUMBERS:
       return TypeInfo::Number();
     case CompareIC::OBJECTS:
+    case CompareIC::KNOWN_OBJECTS:
       // TODO(kasperl): We really need a type for JS objects here.
       return TypeInfo::NonPrimitive();
     case CompareIC::GENERIC:
     default:
       return unknown;
   }
 }
 
 
 TypeInfo TypeFeedbackOracle::IncrementType(CountOperation* expr) {
@@ skipping 188 matching lines @@
   USE(maybe_result);
 #ifdef DEBUG
   Object* result = NULL;
   // Dictionary has been allocated with sufficient size for all elements.
   ASSERT(maybe_result->ToObject(&result));
   ASSERT(*dictionary_ == result);
 #endif
 }
 
 } }  // namespace v8::internal