Revert "Turn the NumberToStringStub into a hydrogen stub."

src/hydrogen.cc

Index: src/hydrogen.cc
diff --git a/src/hydrogen.cc b/src/hydrogen.cc
index 3ce9a948f3ec1c0d2ab91fdae23aa70483b97e1c..50882a8a7f899e657076b55d7be7a1feedbcc191 100644
--- a/src/hydrogen.cc
+++ b/src/hydrogen.cc
@@ -1273,142 +1273,6 @@ void HGraphBuilder::BuildTransitionElementsKind(HValue* object,
 }
 
 
-HValue* HGraphBuilder::BuildLookupNumberStringCache(
-    HValue* object,
-    HIfContinuation* continuation) {
-  // Create a joinable continuation.
-  HIfContinuation found(graph()->CreateBasicBlock(),
-                        graph()->CreateBasicBlock());
-
-  // Load the number string cache.
-  HValue* number_string_cache =
-      Add<HLoadRoot>(Heap::kNumberStringCacheRootIndex);
-
-  // Make the hash maks from the length of the number string cache. It
-  // contains two elements (number and string) for each cache entry.
-  HValue* mask = AddLoadFixedArrayLength(number_string_cache);
-  mask->set_type(HType::Smi());
-  mask = Add<HSar>(mask, graph()->GetConstant1());
-  mask = Add<HSub>(mask, graph()->GetConstant1());
-
-  // Check whether object is a smi.
-  IfBuilder if_objectissmi(this);
-  if_objectissmi.If<HIsSmiAndBranch>(object);
-  if_objectissmi.Then();
-  {
-    // Compute hash for smi similar to smi_get_hash().
-    HValue* hash = Add<HBitwise>(Token::BIT_AND, object, mask);
-
-    // Load the key.
-    HValue* key_index = Add<HShl>(hash, graph()->GetConstant1());
-    HValue* key = AddFastElementAccess(number_string_cache, key_index,
-                                       NULL, NULL, FAST_ELEMENTS, false,
-                                       ALLOW_RETURN_HOLE, STANDARD_STORE);
-
-    // Check if object == key.
-    IfBuilder if_objectiskey(this);
-    if_objectiskey.If<HCompareObjectEqAndBranch>(key, object);
-    if_objectiskey.Then();
-    {
-      // Make the key_index available.
-      Push(key_index);
-    }
-    if_objectiskey.JoinContinuation(&found);
-  }
-  if_objectissmi.Else();
-  {
-    // Check if object is a heap number.
-    IfBuilder if_objectisnumber(this);
-    if_objectisnumber.If<HCompareMap>(
-        object, isolate()->factory()->heap_number_map());
-    if_objectisnumber.Then();
-    {
-      // Compute hash for heap number similar to double_get_hash().
-      HValue* low = Add<HLoadNamedField>(
-          object, HObjectAccess::ForHeapNumberValueLowestBits());
-      HValue* high = Add<HLoadNamedField>(
-          object, HObjectAccess::ForHeapNumberValueHighestBits());
-      HValue* hash = Add<HBitwise>(Token::BIT_XOR, low, high);
-      hash = Add<HBitwise>(Token::BIT_AND, hash, mask);
-
-      // Load the key.
-      HValue* key_index = Add<HShl>(hash, graph()->GetConstant1());
-      HValue* key = AddFastElementAccess(number_string_cache, key_index,
-                                        NULL, NULL, FAST_ELEMENTS, false,
-                                        ALLOW_RETURN_HOLE, STANDARD_STORE);
-
-      // Check if key is a heap number.
-      IfBuilder if_keyisnumber(this);
-      if_keyisnumber.IfNot<HIsSmiAndBranch>(key);
-      if_keyisnumber.AndIf<HCompareMap>(
-          key, isolate()->factory()->heap_number_map());
-      if_keyisnumber.Then();
-      {
-        // Check if values of key and object match.
-        IfBuilder if_keyeqobject(this);
-        if_keyeqobject.If<HCompareNumericAndBranch>(
-            Add<HLoadNamedField>(key, HObjectAccess::ForHeapNumberValue()),
-            Add<HLoadNamedField>(object, HObjectAccess::ForHeapNumberValue()),
-            Token::EQ);
-        if_keyeqobject.Then();
-        {
-          // Make the key_index available.
-          Push(key_index);
-        }
-        if_keyeqobject.JoinContinuation(&found);
-      }
-      if_keyisnumber.JoinContinuation(&found);
-    }
-    if_objectisnumber.JoinContinuation(&found);
-  }
-  if_objectissmi.End();
-
-  // Check for cache hit.
-  IfBuilder if_found(this, &found);
-  if_found.Then();
-
-  // Load the value in case of cache hit.
-  HValue* key_index = Pop();
-  HValue* value_index = Add<HAdd>(key_index, graph()->GetConstant1());
-  HValue* value = AddFastElementAccess(number_string_cache, value_index,
-                                      NULL, NULL, FAST_ELEMENTS, false,
-                                      ALLOW_RETURN_HOLE, STANDARD_STORE);
-  AddIncrementCounter(isolate()->counters()->number_to_string_native());
-
-  if_found.CaptureContinuation(continuation);
-
-  // The value is only available in true branch of continuation.
-  return value;
-}
-
-
-HValue* HGraphBuilder::BuildNumberToString(HValue* number) {
-  NoObservableSideEffectsScope scope(this);
-
-  // Lookup the number in the number string cache.
-  HIfContinuation continuation;
-  HValue* value = BuildLookupNumberStringCache(number, &continuation);
-  IfBuilder if_found(this, &continuation);
-  if_found.Then();
-
-  // Cache hit.
-  Push(value);
-
-  if_found.Else();
-
-  // Cache miss, fallback to runtime.
-  Add<HPushArgument>(number);
-  Push(Add<HCallRuntime>(
-          isolate()->factory()->empty_string(),
-          Runtime::FunctionForId(Runtime::kNumberToStringSkipCache),
-          1));
-
-  if_found.End();
-
-  return Pop();
-}
-
-
 HInstruction* HGraphBuilder::BuildUncheckedMonomorphicElementAccess(
     HValue* checked_object,
     HValue* key,
@@ -9145,10 +9009,12 @@ void HOptimizedGraphBuilder::GenerateGetFromCache(CallRuntime* call) {
 // Fast support for number to string.
 void HOptimizedGraphBuilder::GenerateNumberToString(CallRuntime* call) {
   ASSERT_EQ(1, call->arguments()->length());
-  CHECK_ALIVE(VisitForValue(call->arguments()->at(0)));
-  HValue* number = Pop();
-  HValue* result = BuildNumberToString(number);
-  return ast_context()->ReturnValue(result);
+  CHECK_ALIVE(VisitArgumentList(call->arguments()));
+  HValue* context = environment()->context();
+  HCallStub* result =
+      new(zone()) HCallStub(context, CodeStub::NumberToString, 1);
+  Drop(1);
+  return ast_context()->ReturnInstruction(result, call->id());
 }