Load constants from the DescriptorArray

BUG=
R=jkummerow@chromium.org

Review URL: https://codereview.chromium.org/442763002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@22899 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/arm/stub-cache-arm.cc

@@ -841,14 +841,6 @@ void NamedStoreHandlerCompiler::FrontendFooter(Handle<Name> name, Label* miss) {
 }
 
 
-void NamedLoadHandlerCompiler::GenerateLoadField(
-    Register reg, FieldIndex field, Representation representation) {
-  if (!reg.is(receiver())) __ mov(receiver(), reg);
-  LoadFieldStub stub(isolate(), field);
-  GenerateTailCall(masm(), stub.GetCode());
-}
-
-
 void NamedLoadHandlerCompiler::GenerateLoadConstant(Handle<Object> value) {
   // Return the constant value.
   __ Move(r0, value);

src/arm64/stub-cache-arm64.cc

@@ -797,21 +797,6 @@ void NamedStoreHandlerCompiler::FrontendFooter(Handle<Name> name, Label* miss) {
 }
 
 
-void NamedLoadHandlerCompiler::GenerateLoadField(
-    Register reg, FieldIndex field, Representation representation) {
-  __ Mov(receiver(), reg);
-  LoadFieldStub stub(isolate(), field);
-  GenerateTailCall(masm(), stub.GetCode());
-}
-
-
-void NamedLoadHandlerCompiler::GenerateLoadConstant(Handle<Object> value) {
-  // Return the constant value.
-  __ LoadObject(x0, value);
-  __ Ret();
-}
-
-
 void NamedLoadHandlerCompiler::GenerateLoadCallback(
     Register reg, Handle<ExecutableAccessorInfo> callback) {
   DCHECK(!AreAliased(scratch2(), scratch3(), scratch4(), reg));

src/code-stubs-hydrogen.cc

@@ -590,7 +590,24 @@ Handle<Code> LoadFieldStub::GenerateCode() {
 }
 
 
-template<>
+template <>
+HValue* CodeStubGraphBuilder<LoadConstantStub>::BuildCodeStub() {
+  HValue* map = AddLoadMap(GetParameter(0), NULL);
+  HObjectAccess descriptors_access = HObjectAccess::ForObservableJSObjectOffset(
+      Map::kDescriptorsOffset, Representation::Tagged());
+  HValue* descriptors =
+      Add<HLoadNamedField>(map, static_cast<HValue*>(NULL), descriptors_access);
+  HObjectAccess value_access = HObjectAccess::ForObservableJSObjectOffset(
+      DescriptorArray::GetValueOffset(casted_stub()->descriptor()));
+  return Add<HLoadNamedField>(descriptors, static_cast<HValue*>(NULL),
+                              value_access);
+}
+
+
+Handle<Code> LoadConstantStub::GenerateCode() { return DoGenerateCode(this); }
+
+
+template <>
 HValue* CodeStubGraphBuilder<StringLengthStub>::BuildCodeStub() {
   HValue* string = BuildLoadNamedField(GetParameter(0),
       FieldIndex::ForInObjectOffset(JSValue::kValueOffset));

src/code-stubs.cc

@@ -613,20 +613,20 @@ void KeyedLoadGenericStub::InitializeInterfaceDescriptor(
 }
 
 
-void LoadFieldStub::InitializeInterfaceDescriptor(
+void HandlerStub::InitializeInterfaceDescriptor(
     CodeStubInterfaceDescriptor* descriptor) {
-  Register registers[] = { InterfaceDescriptor::ContextRegister(),
-                           LoadIC::ReceiverRegister() };
-  descriptor->Initialize(MajorKey(), ARRAY_SIZE(registers), registers);
-}
-
-
-void StringLengthStub::InitializeInterfaceDescriptor(
-    CodeStubInterfaceDescriptor* descriptor) {
-  Register registers[] = { InterfaceDescriptor::ContextRegister(),
-                           LoadIC::ReceiverRegister(),
-                           LoadIC::NameRegister() };
-  descriptor->Initialize(MajorKey(), ARRAY_SIZE(registers), registers);
+  if (kind() == Code::LOAD_IC) {
+    Register registers[] = {InterfaceDescriptor::ContextRegister(),
+                            LoadIC::ReceiverRegister(), LoadIC::NameRegister()};
+    descriptor->Initialize(MajorKey(), ARRAY_SIZE(registers), registers);
+  } else {
+    DCHECK_EQ(Code::STORE_IC, kind());
+    Register registers[] = {InterfaceDescriptor::ContextRegister(),
+                            StoreIC::ReceiverRegister(),
+                            StoreIC::NameRegister(), StoreIC::ValueRegister()};
+    descriptor->Initialize(MajorKey(), ARRAY_SIZE(registers), registers,
+                           FUNCTION_ADDR(StoreIC_MissFromStubFailure));
+  }
 }
 
 
@@ -653,17 +653,6 @@ void ElementsTransitionAndStoreStub::InitializeInterfaceDescriptor(
 }
 
 
-void StoreGlobalStub::InitializeInterfaceDescriptor(
-    CodeStubInterfaceDescriptor* descriptor) {
-  Register registers[] = { InterfaceDescriptor::ContextRegister(),
-                           StoreIC::ReceiverRegister(),
-                           StoreIC::NameRegister(),
-                           StoreIC::ValueRegister() };
-  descriptor->Initialize(MajorKey(), ARRAY_SIZE(registers), registers,
-                         FUNCTION_ADDR(StoreIC_MissFromStubFailure));
-}
-
-
 void InstanceofStub::InitializeInterfaceDescriptor(
     CodeStubInterfaceDescriptor* descriptor) {
   Register registers[] = { InterfaceDescriptor::ContextRegister(),

src/code-stubs.h

@@ -76,6 +76,7 @@ namespace internal {
   V(CallApiGetter)                          \
   /* IC Handler stubs */                    \
   V(LoadField)                              \
+  V(LoadConstant)                           \
   V(StringLength)
 
 // List of code stubs only used on ARM 32 bits platforms.
@@ -903,6 +904,9 @@ class HandlerStub : public HydrogenCodeStub {
   virtual ExtraICState GetExtraICState() const { return kind(); }
   virtual InlineCacheState GetICState() { return MONOMORPHIC; }
 
+  virtual void InitializeInterfaceDescriptor(
+      CodeStubInterfaceDescriptor* descriptor) V8_OVERRIDE;
+
  protected:
   explicit HandlerStub(Isolate* isolate)
       : HydrogenCodeStub(isolate), bit_field_(0) {}
@@ -922,9 +926,6 @@ class LoadFieldStub: public HandlerStub {
 
   virtual Handle<Code> GenerateCode() V8_OVERRIDE;
 
-  virtual void InitializeInterfaceDescriptor(
-      CodeStubInterfaceDescriptor* descriptor) V8_OVERRIDE;
-
   Representation representation() {
     if (unboxed_double()) return Representation::Double();
     return Representation::Tagged();
@@ -945,12 +946,30 @@ class LoadFieldStub: public HandlerStub {
 };
 
 
+class LoadConstantStub : public HandlerStub {
+ public:
+  LoadConstantStub(Isolate* isolate, int descriptor) : HandlerStub(isolate) {
+    bit_field_ = descriptor;
+  }
+
+  virtual Handle<Code> GenerateCode() V8_OVERRIDE;
+
+  int descriptor() const { return bit_field_; }
+
+ protected:
+  explicit LoadConstantStub(Isolate* isolate);
+  virtual Code::Kind kind() const { return Code::LOAD_IC; }
+  virtual Code::StubType GetStubType() { return Code::FAST; }
+
+ private:
+  virtual CodeStub::Major MajorKey() const { return LoadConstant; }
+};
+
+
 class StringLengthStub: public HandlerStub {
  public:
   explicit StringLengthStub(Isolate* isolate) : HandlerStub(isolate) {}
   virtual Handle<Code> GenerateCode() V8_OVERRIDE;
-  virtual void InitializeInterfaceDescriptor(
-      CodeStubInterfaceDescriptor* descriptor) V8_OVERRIDE;
 
  protected:
   virtual Code::Kind kind() const { return Code::LOAD_IC; }
@@ -992,9 +1011,6 @@ class StoreGlobalStub : public HandlerStub {
 
   virtual Handle<Code> GenerateCode() V8_OVERRIDE;
 
-  virtual void InitializeInterfaceDescriptor(
-      CodeStubInterfaceDescriptor* descriptor) V8_OVERRIDE;
-
   bool is_constant() const {
     return IsConstantBits::decode(bit_field_);
   }

src/ia32/stub-cache-ia32.cc

@@ -810,14 +810,6 @@ void NamedStoreHandlerCompiler::FrontendFooter(Handle<Name> name, Label* miss) {
 }
 
 
-void NamedLoadHandlerCompiler::GenerateLoadField(
-    Register reg, FieldIndex field, Representation representation) {
-  if (!reg.is(receiver())) __ mov(receiver(), reg);
-  LoadFieldStub stub(isolate(), field);
-  GenerateTailCall(masm(), stub.GetCode());
-}
-
-
 void NamedLoadHandlerCompiler::GenerateLoadCallback(
     Register reg, Handle<ExecutableAccessorInfo> callback) {
   // Insert additional parameters into the stack frame above return address.

src/ic.cc

@@ -1089,13 +1089,16 @@ Handle<Code> LoadIC::CompileHandler(LookupIterator* lookup,
     if (receiver_is_holder) {
       return SimpleFieldLoad(field);
     }
-    return compiler.CompileLoadField(name, field, lookup->representation());
+    return compiler.CompileLoadField(name, field);
   }
 
   // -------------- Constant properties --------------
   DCHECK(lookup->property_details().type() == CONSTANT);
-  Handle<Object> constant = lookup->GetDataValue();
-  return compiler.CompileLoadConstant(name, constant);
+  if (receiver_is_holder) {
+    LoadConstantStub stub(isolate(), lookup->GetConstantIndex());
+    return stub.GetCode();
+  }
+  return compiler.CompileLoadConstant(name, lookup->GetConstantIndex());
 }
 
 

src/lookup.cc

@@ -205,8 +205,18 @@ Handle<Object> LookupIterator::FetchValue() const {
 }
 
 
+int LookupIterator::GetConstantIndex() const {
+  DCHECK(has_property_);
+  DCHECK_EQ(DESCRIPTOR, property_encoding_);
+  DCHECK_EQ(v8::internal::CONSTANT, property_details_.type());
+  return descriptor_number();
+}
+
+
 FieldIndex LookupIterator::GetFieldIndex() const {
-  DCHECK_EQ(PROPERTY, state_);
+  DCHECK(has_property_);
+  DCHECK_EQ(DESCRIPTOR, property_encoding_);
+  DCHECK_EQ(v8::internal::FIELD, property_details_.type());
   int index =
       holder_map()->instance_descriptors()->GetFieldIndex(descriptor_number());
   bool is_double = representation().IsDouble();

src/lookup.h

@@ -140,6 +140,7 @@ class LookupIterator V8_FINAL BASE_EMBEDDED {
     return property_details().representation();
   }
   FieldIndex GetFieldIndex() const;
+  int GetConstantIndex() const;
   Handle<PropertyCell> GetPropertyCell() const;
   Handle<Object> GetAccessors() const;
   Handle<Object> GetDataValue() const;

src/mips/stub-cache-mips.cc

@@ -840,14 +840,6 @@ void NamedStoreHandlerCompiler::FrontendFooter(Handle<Name> name, Label* miss) {
 }
 
 
-void NamedLoadHandlerCompiler::GenerateLoadField(
-    Register reg, FieldIndex field, Representation representation) {
-  if (!reg.is(receiver())) __ mov(receiver(), reg);
-  LoadFieldStub stub(isolate(), field);
-  GenerateTailCall(masm(), stub.GetCode());
-}
-
-
 void NamedLoadHandlerCompiler::GenerateLoadConstant(Handle<Object> value) {
   // Return the constant value.
   __ li(v0, value);

src/mips64/stub-cache-mips64.cc

@@ -844,14 +844,6 @@ void NamedStoreHandlerCompiler::FrontendFooter(Handle<Name> name, Label* miss) {
 }
 
 
-void NamedLoadHandlerCompiler::GenerateLoadField(
-    Register reg, FieldIndex field, Representation representation) {
-  if (!reg.is(receiver())) __ mov(receiver(), reg);
-  LoadFieldStub stub(isolate(), field);
-  GenerateTailCall(masm(), stub.GetCode());
-}
-
-
 void NamedLoadHandlerCompiler::GenerateLoadConstant(Handle<Object> value) {
   // Return the constant value.
   __ li(v0, value);

src/objects-inl.h

@@ -2982,6 +2982,11 @@ Object** DescriptorArray::GetValueSlot(int descriptor_number) {
 }
 
 
+int DescriptorArray::GetValueOffset(int descriptor_number) {
+  return OffsetOfElementAt(ToValueIndex(descriptor_number));
+}
+
+
 Object* DescriptorArray::GetValue(int descriptor_number) {
   DCHECK(descriptor_number < number_of_descriptors());
   return get(ToValueIndex(descriptor_number));

src/objects.h

@@ -3417,6 +3417,7 @@ class DescriptorArray: public FixedArray {
   inline Object* GetValue(int descriptor_number);
   inline void SetValue(int descriptor_number, Object* value);
   inline Object** GetValueSlot(int descriptor_number);
+  static inline int GetValueOffset(int descriptor_number);
   inline Object** GetDescriptorStartSlot(int descriptor_number);
   inline Object** GetDescriptorEndSlot(int descriptor_number);
   inline PropertyDetails GetDetails(int descriptor_number);

src/stub-cache.cc

@@ -842,18 +842,22 @@ void PropertyHandlerCompiler::NonexistentFrontendHeader(Handle<Name> name,
 }
 
 
-Handle<Code> NamedLoadHandlerCompiler::CompileLoadField(
-    Handle<Name> name, FieldIndex field, Representation representation) {
+Handle<Code> NamedLoadHandlerCompiler::CompileLoadField(Handle<Name> name,
+                                                        FieldIndex field) {
   Register reg = Frontend(receiver(), name);
-  GenerateLoadField(reg, field, representation);
+  __ Move(receiver(), reg);
+  LoadFieldStub stub(isolate(), field);
+  GenerateTailCall(masm(), stub.GetCode());
   return GetCode(kind(), Code::FAST, name);
 }
 
 
-Handle<Code> NamedLoadHandlerCompiler::CompileLoadConstant(
-    Handle<Name> name, Handle<Object> value) {
-  Frontend(receiver(), name);
-  GenerateLoadConstant(value);
+Handle<Code> NamedLoadHandlerCompiler::CompileLoadConstant(Handle<Name> name,
+                                                           int constant_index) {
+  Register reg = Frontend(receiver(), name);
+  __ Move(receiver(), reg);
+  LoadConstantStub stub(isolate(), constant_index);
+  GenerateTailCall(masm(), stub.GetCode());
   return GetCode(kind(), Code::FAST, name);
 }
 
@@ -917,7 +921,9 @@ void NamedLoadHandlerCompiler::GenerateLoadPostInterceptor(
   Register reg = Frontend(interceptor_reg, name);
 
   if (lookup->IsField()) {
-    GenerateLoadField(reg, lookup->GetFieldIndex(), lookup->representation());
+    __ Move(receiver(), reg);
+    LoadFieldStub stub(isolate(), lookup->GetFieldIndex());
+    GenerateTailCall(masm(), stub.GetCode());
   } else {
     DCHECK(lookup->type() == CALLBACKS);
     Handle<ExecutableAccessorInfo> callback(

src/stub-cache.h

@@ -463,8 +463,7 @@ class NamedLoadHandlerCompiler : public PropertyHandlerCompiler {
 
   virtual ~NamedLoadHandlerCompiler() {}
 
-  Handle<Code> CompileLoadField(Handle<Name> name, FieldIndex index,
-                                Representation representation);
+  Handle<Code> CompileLoadField(Handle<Name> name, FieldIndex index);
 
   Handle<Code> CompileLoadCallback(Handle<Name> name,
                                    Handle<ExecutableAccessorInfo> callback);
@@ -472,7 +471,7 @@ class NamedLoadHandlerCompiler : public PropertyHandlerCompiler {
   Handle<Code> CompileLoadCallback(Handle<Name> name,
                                    const CallOptimization& call_optimization);
 
-  Handle<Code> CompileLoadConstant(Handle<Name> name, Handle<Object> value);
+  Handle<Code> CompileLoadConstant(Handle<Name> name, int constant_index);
 
   Handle<Code> CompileLoadInterceptor(Handle<Name> name);
 
@@ -519,9 +518,6 @@ class NamedLoadHandlerCompiler : public PropertyHandlerCompiler {
 
  private:
   Handle<Code> CompileLoadNonexistent(Handle<Name> name);
-  void GenerateLoadField(Register reg,
-                         FieldIndex field,
-                         Representation representation);
   void GenerateLoadConstant(Handle<Object> value);
   void GenerateLoadCallback(Register reg,
                             Handle<ExecutableAccessorInfo> callback);

src/x64/stub-cache-x64.cc

@@ -751,14 +751,6 @@ void NamedStoreHandlerCompiler::FrontendFooter(Handle<Name> name, Label* miss) {
 }
 
 
-void NamedLoadHandlerCompiler::GenerateLoadField(
-    Register reg, FieldIndex field, Representation representation) {
-  if (!reg.is(receiver())) __ movp(receiver(), reg);
-  LoadFieldStub stub(isolate(), field);
-  GenerateTailCall(masm(), stub.GetCode());
-}
-
-
 void NamedLoadHandlerCompiler::GenerateLoadCallback(
     Register reg, Handle<ExecutableAccessorInfo> callback) {
   // Insert additional parameters into the stack frame above return address.

src/x87/stub-cache-x87.cc

@@ -809,14 +809,6 @@ void NamedStoreHandlerCompiler::FrontendFooter(Handle<Name> name, Label* miss) {
 }
 
 
-void NamedLoadHandlerCompiler::GenerateLoadField(
-    Register reg, FieldIndex field, Representation representation) {
-  if (!reg.is(receiver())) __ mov(receiver(), reg);
-  LoadFieldStub stub(isolate(), field);
-  GenerateTailCall(masm(), stub.GetCode());
-}
-
-
 void NamedLoadHandlerCompiler::GenerateLoadCallback(
     Register reg, Handle<ExecutableAccessorInfo> callback) {
   // Insert additional parameters into the stack frame above return address.