[compiler] Drop the CompareNilIC.

src/code-stubs-hydrogen.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/code-stubs.h"
 
 #include "src/bailout-reason.h"
 #include "src/crankshaft/hydrogen.h"
 #include "src/crankshaft/lithium.h"
 #include "src/field-index.h"
@@ skipping 1401 matching lines @@
   return BuildInternalArrayConstructor(kind, MULTIPLE);
 }
 
 
 Handle<Code> InternalArrayNArgumentsConstructorStub::GenerateCode() {
   return DoGenerateCode(this);
 }
 
 
 template <>
-HValue* CodeStubGraphBuilder<CompareNilICStub>::BuildCodeInitializedStub() {
-  Isolate* isolate = graph()->isolate();
-  CompareNilICStub* stub = casted_stub();
-  HIfContinuation continuation;
-  Handle<Map> sentinel_map(isolate->heap()->meta_map());
-  Type* type = stub->GetType(zone(), sentinel_map);
-  BuildCompareNil(GetParameter(0), type, &continuation, kEmbedMapsViaWeakCells);
-  IfBuilder if_nil(this, &continuation);
-  if_nil.Then();
-  if (continuation.IsFalseReachable()) {
-    if_nil.Else();
-    if_nil.Return(graph()->GetConstantFalse());
-  }
-  if_nil.End();
-  return continuation.IsTrueReachable() ? graph()->GetConstantTrue()
-                                        : graph()->GetConstantUndefined();
-}
-
-
-Handle<Code> CompareNilICStub::GenerateCode() {
-  return DoGenerateCode(this);
-}
-
-
-template <>
 HValue* CodeStubGraphBuilder<BinaryOpICStub>::BuildCodeInitializedStub() {
   BinaryOpICState state = casted_stub()->state();
 
   HValue* left = GetParameter(BinaryOpICStub::kLeft);
   HValue* right = GetParameter(BinaryOpICStub::kRight);
 
   Type* left_type = state.GetLeftType();
   Type* right_type = state.GetRightType();
   Type* result_type = state.GetResultType();
 
@@ skipping 967 matching lines @@
   return Pop();
 }
 
 
 Handle<Code> KeyedLoadGenericStub::GenerateCode() {
   return DoGenerateCode(this);
 }
 
 }  // namespace internal
 }  // namespace v8