Update V8 to version 4.1.0.21

This is a cherry-pick of all commits up to and including the
4.1.0.21 cherry-pick in Chromium.

Original commit message:

Version 4.1.0.21 (cherry-pick)

Merged 206e9136bde0f2b5ae8cb77afbb1e7833e5bd412

Unlink pages from the space page list after evacuation.

BUG=430201
LOG=N
R=jkummerow@chromium.org

Review URL: https://codereview.chromium.org/953813002

Cr-Commit-Position: refs/branch-heads/4.1@{#22}
Cr-Branched-From: 2e08d2a7aa9d65d269d8c57aba82eb38a8cb0a18-refs/heads/candidates@{#25353}

---

FPIIM-449

Change-Id: I8c23c7bbb70772b4858fe8a47b64fa97ee0d1f8c
diff --git a/src/type-feedback-vector.h b/src/type-feedback-vector.h
index b6fadba..864f336 100644
--- a/src/type-feedback-vector.h
+++ b/src/type-feedback-vector.h
@@ -5,6 +5,8 @@
 #ifndef V8_TYPE_FEEDBACK_VECTOR_H_
 #define V8_TYPE_FEEDBACK_VECTOR_H_
 
+#include <vector>
+
 #include "src/checks.h"
 #include "src/elements-kind.h"
 #include "src/heap/heap.h"
@@ -14,6 +16,51 @@
 namespace v8 {
 namespace internal {
 
+class FeedbackVectorSpec {
+ public:
+  FeedbackVectorSpec() : slots_(0), ic_slots_(0) {}
+  FeedbackVectorSpec(int slots, int ic_slots)
+      : slots_(slots), ic_slots_(ic_slots) {
+    if (FLAG_vector_ics) ic_slot_kinds_.resize(ic_slots);
+  }
+
+  int slots() const { return slots_; }
+  void increase_slots(int count) { slots_ += count; }
+
+  int ic_slots() const { return ic_slots_; }
+  void increase_ic_slots(int count) {
+    ic_slots_ += count;
+    if (FLAG_vector_ics) ic_slot_kinds_.resize(ic_slots_);
+  }
+
+  void SetKind(int ic_slot, Code::Kind kind) {
+    DCHECK(FLAG_vector_ics);
+    ic_slot_kinds_[ic_slot] = kind;
+  }
+
+  Code::Kind GetKind(int ic_slot) const {
+    DCHECK(FLAG_vector_ics);
+    return static_cast<Code::Kind>(ic_slot_kinds_.at(ic_slot));
+  }
+
+ private:
+  int slots_;
+  int ic_slots_;
+  std::vector<unsigned char> ic_slot_kinds_;
+};
+
+
+// The shape of the TypeFeedbackVector is an array with:
+// 0: first_ic_slot_index (== length() if no ic slots are present)
+// 1: ics_with_types
+// 2: ics_with_generic_info
+// 3: type information for ic slots, if any
+// ...
+// N: first feedback slot (N >= 3)
+// ...
+// [<first_ic_slot_index>: feedback slot]
+// ...to length() - 1
+//
 class TypeFeedbackVector : public FixedArray {
  public:
   // Casting.
@@ -22,9 +69,103 @@
     return reinterpret_cast<TypeFeedbackVector*>(obj);
   }
 
+  static const int kReservedIndexCount = 3;
+  static const int kFirstICSlotIndex = 0;
+  static const int kWithTypesIndex = 1;
+  static const int kGenericCountIndex = 2;
+
+  int first_ic_slot_index() const {
+    DCHECK(length() >= kReservedIndexCount);
+    return Smi::cast(get(kFirstICSlotIndex))->value();
+  }
+
+  int ic_with_type_info_count() {
+    return length() > 0 ? Smi::cast(get(kWithTypesIndex))->value() : 0;
+  }
+
+  void change_ic_with_type_info_count(int delta) {
+    if (delta == 0) return;
+    int value = ic_with_type_info_count() + delta;
+    // Could go negative because of the debugger.
+    if (value >= 0) {
+      set(kWithTypesIndex, Smi::FromInt(value));
+    }
+  }
+
+  int ic_generic_count() {
+    return length() > 0 ? Smi::cast(get(kGenericCountIndex))->value() : 0;
+  }
+
+  void change_ic_generic_count(int delta) {
+    if (delta == 0) return;
+    int value = ic_generic_count() + delta;
+    if (value >= 0) {
+      set(kGenericCountIndex, Smi::FromInt(value));
+    }
+  }
+
+  inline int ic_metadata_length() const;
+
+  int Slots() const {
+    if (length() == 0) return 0;
+    return Max(
+        0, first_ic_slot_index() - ic_metadata_length() - kReservedIndexCount);
+  }
+
+  int ICSlots() const {
+    if (length() == 0) return 0;
+    return length() - first_ic_slot_index();
+  }
+
+  // Conversion from a slot or ic slot to an integer index to the underlying
+  // array.
+  int GetIndex(FeedbackVectorSlot slot) const {
+    return kReservedIndexCount + ic_metadata_length() + slot.ToInt();
+  }
+
+  int GetIndex(FeedbackVectorICSlot slot) const {
+    int first_ic_slot = first_ic_slot_index();
+    DCHECK(slot.ToInt() < ICSlots());
+    return first_ic_slot + slot.ToInt();
+  }
+
+  // Conversion from an integer index to either a slot or an ic slot. The caller
+  // should know what kind she expects.
+  FeedbackVectorSlot ToSlot(int index) const {
+    DCHECK(index >= kReservedIndexCount && index < first_ic_slot_index());
+    return FeedbackVectorSlot(index - ic_metadata_length() -
+                              kReservedIndexCount);
+  }
+
+  FeedbackVectorICSlot ToICSlot(int index) const {
+    DCHECK(index >= first_ic_slot_index() && index < length());
+    return FeedbackVectorICSlot(index - first_ic_slot_index());
+  }
+
+  Object* Get(FeedbackVectorSlot slot) const { return get(GetIndex(slot)); }
+  void Set(FeedbackVectorSlot slot, Object* value,
+           WriteBarrierMode mode = UPDATE_WRITE_BARRIER) {
+    set(GetIndex(slot), value, mode);
+  }
+
+  Object* Get(FeedbackVectorICSlot slot) const { return get(GetIndex(slot)); }
+  void Set(FeedbackVectorICSlot slot, Object* value,
+           WriteBarrierMode mode = UPDATE_WRITE_BARRIER) {
+    set(GetIndex(slot), value, mode);
+  }
+
+  // IC slots need metadata to recognize the type of IC.
+  Code::Kind GetKind(FeedbackVectorICSlot slot) const;
+
+  static Handle<TypeFeedbackVector> Allocate(Isolate* isolate,
+                                             const FeedbackVectorSpec& spec);
+
   static Handle<TypeFeedbackVector> Copy(Isolate* isolate,
                                          Handle<TypeFeedbackVector> vector);
 
+  // Clears the vector slots and the vector ic slots.
+  void ClearSlots(SharedFunctionInfo* shared);
+
   // The object that indicates an uninitialized cache.
   static inline Handle<Object> UninitializedSentinel(Isolate* isolate);
 
@@ -47,8 +188,182 @@
   static inline Object* RawUninitializedSentinel(Heap* heap);
 
  private:
+  enum VectorICKind {
+    KindUnused = 0x0,
+    KindCallIC = 0x1,
+    KindLoadIC = 0x2,
+    KindKeyedLoadIC = 0x3
+  };
+
+  static const int kVectorICKindBits = 2;
+  static VectorICKind FromCodeKind(Code::Kind kind);
+  static Code::Kind FromVectorICKind(VectorICKind kind);
+  void SetKind(FeedbackVectorICSlot slot, Code::Kind kind);
+
+  typedef BitSetComputer<VectorICKind, kVectorICKindBits, kSmiValueSize,
+                         uint32_t> VectorICComputer;
+
   DISALLOW_IMPLICIT_CONSTRUCTORS(TypeFeedbackVector);
 };
+
+
+// A FeedbackNexus is the combination of a TypeFeedbackVector and a slot.
+// Derived classes customize the update and retrieval of feedback.
+class FeedbackNexus {
+ public:
+  FeedbackNexus(Handle<TypeFeedbackVector> vector, FeedbackVectorICSlot slot)
+      : vector_handle_(vector), vector_(NULL), slot_(slot) {}
+  FeedbackNexus(TypeFeedbackVector* vector, FeedbackVectorICSlot slot)
+      : vector_(vector), slot_(slot) {}
+  virtual ~FeedbackNexus() {}
+
+  Handle<TypeFeedbackVector> vector_handle() const {
+    DCHECK(vector_ == NULL);
+    return vector_handle_;
+  }
+  TypeFeedbackVector* vector() const {
+    return vector_handle_.is_null() ? vector_ : *vector_handle_;
+  }
+  FeedbackVectorICSlot slot() const { return slot_; }
+
+  InlineCacheState ic_state() const { return StateFromFeedback(); }
+  Map* FindFirstMap() const {
+    MapHandleList maps;
+    ExtractMaps(&maps);
+    if (maps.length() > 0) return *maps.at(0);
+    return NULL;
+  }
+
+  // TODO(mvstanton): remove FindAllMaps, it didn't survive a code review.
+  void FindAllMaps(MapHandleList* maps) const { ExtractMaps(maps); }
+
+  virtual InlineCacheState StateFromFeedback() const = 0;
+  virtual int ExtractMaps(MapHandleList* maps) const = 0;
+  virtual MaybeHandle<Code> FindHandlerForMap(Handle<Map> map) const = 0;
+  virtual bool FindHandlers(CodeHandleList* code_list, int length = -1) const {
+    return length == 0;
+  }
+  virtual Name* FindFirstName() const { return NULL; }
+
+  Object* GetFeedback() const { return vector()->Get(slot()); }
+
+ protected:
+  Isolate* GetIsolate() const { return vector()->GetIsolate(); }
+
+  void SetFeedback(Object* feedback,
+                   WriteBarrierMode mode = UPDATE_WRITE_BARRIER) {
+    vector()->Set(slot(), feedback, mode);
+  }
+
+  Handle<FixedArray> EnsureArrayOfSize(int length);
+  void InstallHandlers(int start_index, TypeHandleList* types,
+                       CodeHandleList* handlers);
+  int ExtractMaps(int start_index, MapHandleList* maps) const;
+  MaybeHandle<Code> FindHandlerForMap(int start_index, Handle<Map> map) const;
+  bool FindHandlers(int start_index, CodeHandleList* code_list,
+                    int length) const;
+
+ private:
+  // The reason for having a vector handle and a raw pointer is that we can and
+  // should use handles during IC miss, but not during GC when we clear ICs. If
+  // you have a handle to the vector that is better because more operations can
+  // be done, like allocation.
+  Handle<TypeFeedbackVector> vector_handle_;
+  TypeFeedbackVector* vector_;
+  FeedbackVectorICSlot slot_;
+};
+
+
+class CallICNexus : public FeedbackNexus {
+ public:
+  CallICNexus(Handle<TypeFeedbackVector> vector, FeedbackVectorICSlot slot)
+      : FeedbackNexus(vector, slot) {
+    DCHECK(vector->GetKind(slot) == Code::CALL_IC);
+  }
+  CallICNexus(TypeFeedbackVector* vector, FeedbackVectorICSlot slot)
+      : FeedbackNexus(vector, slot) {
+    DCHECK(vector->GetKind(slot) == Code::CALL_IC);
+  }
+
+  void Clear(Code* host);
+
+  void ConfigureUninitialized();
+  void ConfigureGeneric();
+  void ConfigureMonomorphicArray();
+  void ConfigureMonomorphic(Handle<JSFunction> function);
+
+  InlineCacheState StateFromFeedback() const OVERRIDE;
+
+  int ExtractMaps(MapHandleList* maps) const OVERRIDE {
+    // CallICs don't record map feedback.
+    return 0;
+  }
+  MaybeHandle<Code> FindHandlerForMap(Handle<Map> map) const OVERRIDE {
+    return MaybeHandle<Code>();
+  }
+  virtual bool FindHandlers(CodeHandleList* code_list,
+                            int length = -1) const OVERRIDE {
+    return length == 0;
+  }
+};
+
+
+class LoadICNexus : public FeedbackNexus {
+ public:
+  LoadICNexus(Handle<TypeFeedbackVector> vector, FeedbackVectorICSlot slot)
+      : FeedbackNexus(vector, slot) {
+    DCHECK(vector->GetKind(slot) == Code::LOAD_IC);
+  }
+  LoadICNexus(TypeFeedbackVector* vector, FeedbackVectorICSlot slot)
+      : FeedbackNexus(vector, slot) {
+    DCHECK(vector->GetKind(slot) == Code::LOAD_IC);
+  }
+
+  void Clear(Code* host);
+
+  void ConfigureMegamorphic();
+  void ConfigurePremonomorphic();
+  void ConfigureMonomorphic(Handle<HeapType> type, Handle<Code> handler);
+
+  void ConfigurePolymorphic(TypeHandleList* types, CodeHandleList* handlers);
+
+  InlineCacheState StateFromFeedback() const OVERRIDE;
+  int ExtractMaps(MapHandleList* maps) const OVERRIDE;
+  MaybeHandle<Code> FindHandlerForMap(Handle<Map> map) const OVERRIDE;
+  virtual bool FindHandlers(CodeHandleList* code_list,
+                            int length = -1) const OVERRIDE;
+};
+
+
+class KeyedLoadICNexus : public FeedbackNexus {
+ public:
+  KeyedLoadICNexus(Handle<TypeFeedbackVector> vector, FeedbackVectorICSlot slot)
+      : FeedbackNexus(vector, slot) {
+    DCHECK(vector->GetKind(slot) == Code::KEYED_LOAD_IC);
+  }
+  KeyedLoadICNexus(TypeFeedbackVector* vector, FeedbackVectorICSlot slot)
+      : FeedbackNexus(vector, slot) {
+    DCHECK(vector->GetKind(slot) == Code::KEYED_LOAD_IC);
+  }
+
+  void Clear(Code* host);
+
+  void ConfigureGeneric();
+  void ConfigurePremonomorphic();
+  // name can be a null handle for element loads.
+  void ConfigureMonomorphic(Handle<Name> name, Handle<HeapType> type,
+                            Handle<Code> handler);
+  // name can be null.
+  void ConfigurePolymorphic(Handle<Name> name, TypeHandleList* types,
+                            CodeHandleList* handlers);
+
+  InlineCacheState StateFromFeedback() const OVERRIDE;
+  int ExtractMaps(MapHandleList* maps) const OVERRIDE;
+  MaybeHandle<Code> FindHandlerForMap(Handle<Map> map) const OVERRIDE;
+  virtual bool FindHandlers(CodeHandleList* code_list,
+                            int length = -1) const OVERRIDE;
+  Name* FindFirstName() const OVERRIDE;
+};
 }
 }  // namespace v8::internal