Revert of [compiler] Drop the CompareNilIC.

src/code-stubs.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 <sstream>
 
 #include "src/bootstrapper.h"
 #include "src/compiler/code-stub-assembler.h"
@@ skipping 433 matching lines @@
       DCHECK(*known_map_ != NULL);
       GenerateKnownReceivers(masm);
       break;
     case CompareICState::GENERIC:
       GenerateGeneric(masm);
       break;
   }
 }
 
 
+void CompareNilICStub::UpdateStatus(Handle<Object> object) {
+  State state = this->state();
+  DCHECK(!state.Contains(GENERIC));
+  State old_state = state;
+  if (object->IsNull()) {
+    state.Add(NULL_TYPE);
+  } else if (object->IsUndefined()) {
+    state.Add(UNDEFINED);
+  } else if (object->IsUndetectableObject() || object->IsSmi()) {
+    state.RemoveAll();
+    state.Add(GENERIC);
+  } else if (IsMonomorphic()) {
+    state.RemoveAll();
+    state.Add(GENERIC);
+  } else {
+    state.Add(MONOMORPHIC_MAP);
+  }
+  TraceTransition(old_state, state);
+  set_sub_minor_key(TypesBits::update(sub_minor_key(), state.ToIntegral()));
+}
+
+
 Handle<Code> TurboFanCodeStub::GenerateCode() {
   const char* name = CodeStub::MajorName(MajorKey());
   Zone zone;
   CallInterfaceDescriptor descriptor(GetCallInterfaceDescriptor());
   compiler::CodeStubAssembler assembler(isolate(), &zone, descriptor,
                                         GetCodeFlags(), name);
   GenerateAssembly(&assembler);
   return assembler.GenerateCode();
 }
 
@@ skipping 15 matching lines @@
   // bug somewhere in our state transition machinery.
   DCHECK(from != to);
   if (!FLAG_trace_ic) return;
   OFStream os(stdout);
   os << "[";
   PrintBaseName(os);
   os << ": " << from << "=>" << to << "]" << std::endl;
 }
 
 
+void CompareNilICStub::PrintBaseName(std::ostream& os) const {  // NOLINT
+  CodeStub::PrintBaseName(os);
+  os << ((nil_value() == kNullValue) ? "(NullValue)" : "(UndefinedValue)");
+}
+
+
+void CompareNilICStub::PrintState(std::ostream& os) const {  // NOLINT
+  os << state();
+}
+
+
 // TODO(svenpanne) Make this a real infix_ostream_iterator.
 class SimpleListPrinter {
  public:
   explicit SimpleListPrinter(std::ostream& os) : os_(os), first_(true) {}
 
   void Add(const char* s) {
     if (first_) {
       first_ = false;
     } else {
       os_ << ",";
     }
     os_ << s;
   }
 
  private:
   std::ostream& os_;
   bool first_;
 };
 
 
+std::ostream& operator<<(std::ostream& os, const CompareNilICStub::State& s) {
+  os << "(";
+  SimpleListPrinter p(os);
+  if (s.IsEmpty()) p.Add("None");
+  if (s.Contains(CompareNilICStub::UNDEFINED)) p.Add("Undefined");
+  if (s.Contains(CompareNilICStub::NULL_TYPE)) p.Add("Null");
+  if (s.Contains(CompareNilICStub::MONOMORPHIC_MAP)) p.Add("MonomorphicMap");
+  if (s.Contains(CompareNilICStub::GENERIC)) p.Add("Generic");
+  return os << ")";
+}
+
+
+Type* CompareNilICStub::GetType(Zone* zone, Handle<Map> map) {
+  State state = this->state();
+  if (state.Contains(CompareNilICStub::GENERIC)) return Type::Any();
+
+  Type* result = Type::None();
+  if (state.Contains(CompareNilICStub::UNDEFINED)) {
+    result = Type::Union(result, Type::Undefined(), zone);
+  }
+  if (state.Contains(CompareNilICStub::NULL_TYPE)) {
+    result = Type::Union(result, Type::Null(), zone);
+  }
+  if (state.Contains(CompareNilICStub::MONOMORPHIC_MAP)) {
+    Type* type = map.is_null() ? Type::Detectable() : Type::Class(map, zone);
+    result = Type::Union(result, type, zone);
+  }
+
+  return result;
+}
+
+
+Type* CompareNilICStub::GetInputType(Zone* zone, Handle<Map> map) {
+  Type* output_type = GetType(zone, map);
+  Type* nil_type = nil_value() == kNullValue ? Type::Null() : Type::Undefined();
+  return Type::Union(output_type, nil_type, zone);
+}
+
+
 void CallICStub::PrintState(std::ostream& os) const {  // NOLINT
   os << state();
 }
 
 
 void JSEntryStub::FinishCode(Handle<Code> code) {
   Handle<FixedArray> handler_table =
       code->GetIsolate()->factory()->NewFixedArray(1, TENURED);
   handler_table->set(0, Smi::FromInt(handler_offset_));
   code->set_handler_table(*handler_table);
@@ skipping 141 matching lines @@
   descriptor->Initialize();
 }
 
 
 void AllocateInNewSpaceStub::InitializeDescriptor(
     CodeStubDescriptor* descriptor) {
   descriptor->Initialize();
 }
 
 
+void CompareNilICStub::InitializeDescriptor(CodeStubDescriptor* descriptor) {
+  descriptor->Initialize(FUNCTION_ADDR(Runtime_CompareNilIC_Miss));
+  descriptor->SetMissHandler(ExternalReference(
+      Runtime::FunctionForId(Runtime::kCompareNilIC_Miss), isolate()));
+}
+
+
 void ToBooleanStub::InitializeDescriptor(CodeStubDescriptor* descriptor) {
   descriptor->Initialize(FUNCTION_ADDR(Runtime_ToBooleanIC_Miss));
   descriptor->SetMissHandler(ExternalReference(
       Runtime::FunctionForId(Runtime::kToBooleanIC_Miss), isolate()));
 }
 
 
 void BinaryOpICStub::InitializeDescriptor(CodeStubDescriptor* descriptor) {
   descriptor->Initialize(FUNCTION_ADDR(Runtime_BinaryOpIC_Miss));
   descriptor->SetMissHandler(ExternalReference(
@@ skipping 227 matching lines @@
   if (type->Is(Type::UntaggedPointer())) {
     return Representation::External();
   }
 
   DCHECK(!type->Is(Type::Untagged()));
   return Representation::Tagged();
 }
 
 }  // namespace internal
 }  // namespace v8