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/bit-vector.h b/src/bit-vector.h
new file mode 100644
index 0000000..9fc747d
--- /dev/null
+++ b/src/bit-vector.h
@@ -0,0 +1,253 @@
+// 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.
+
+#ifndef V8_DATAFLOW_H_
+#define V8_DATAFLOW_H_
+
+#include "src/v8.h"
+
+#include "src/allocation.h"
+#include "src/ast.h"
+#include "src/compiler.h"
+#include "src/zone-inl.h"
+
+namespace v8 {
+namespace internal {
+
+class BitVector : public ZoneObject {
+ public:
+  // Iterator for the elements of this BitVector.
+  class Iterator BASE_EMBEDDED {
+   public:
+    explicit Iterator(BitVector* target)
+        : target_(target),
+          current_index_(0),
+          current_value_(target->data_[0]),
+          current_(-1) {
+      DCHECK(target->data_length_ > 0);
+      Advance();
+    }
+    ~Iterator() {}
+
+    bool Done() const { return current_index_ >= target_->data_length_; }
+    void Advance();
+
+    int Current() const {
+      DCHECK(!Done());
+      return current_;
+    }
+
+   private:
+    uintptr_t SkipZeroBytes(uintptr_t val) {
+      while ((val & 0xFF) == 0) {
+        val >>= 8;
+        current_ += 8;
+      }
+      return val;
+    }
+    uintptr_t SkipZeroBits(uintptr_t val) {
+      while ((val & 0x1) == 0) {
+        val >>= 1;
+        current_++;
+      }
+      return val;
+    }
+
+    BitVector* target_;
+    int current_index_;
+    uintptr_t current_value_;
+    int current_;
+
+    friend class BitVector;
+  };
+
+  static const int kDataBits = kPointerSize * 8;
+  static const int kDataBitShift = kPointerSize == 8 ? 6 : 5;
+  static const uintptr_t kOne = 1;  // This saves some static_casts.
+
+  BitVector(int length, Zone* zone)
+      : length_(length),
+        data_length_(SizeFor(length)),
+        data_(zone->NewArray<uintptr_t>(data_length_)) {
+    DCHECK(length > 0);
+    Clear();
+  }
+
+  BitVector(const BitVector& other, Zone* zone)
+      : length_(other.length()),
+        data_length_(SizeFor(length_)),
+        data_(zone->NewArray<uintptr_t>(data_length_)) {
+    CopyFrom(other);
+  }
+
+  static int SizeFor(int length) { return 1 + ((length - 1) / kDataBits); }
+
+  void CopyFrom(const BitVector& other) {
+    DCHECK(other.length() <= length());
+    for (int i = 0; i < other.data_length_; i++) {
+      data_[i] = other.data_[i];
+    }
+    for (int i = other.data_length_; i < data_length_; i++) {
+      data_[i] = 0;
+    }
+  }
+
+  bool Contains(int i) const {
+    DCHECK(i >= 0 && i < length());
+    uintptr_t block = data_[i / kDataBits];
+    return (block & (kOne << (i % kDataBits))) != 0;
+  }
+
+  void Add(int i) {
+    DCHECK(i >= 0 && i < length());
+    data_[i / kDataBits] |= (kOne << (i % kDataBits));
+  }
+
+  void Remove(int i) {
+    DCHECK(i >= 0 && i < length());
+    data_[i / kDataBits] &= ~(kOne << (i % kDataBits));
+  }
+
+  void Union(const BitVector& other) {
+    DCHECK(other.length() == length());
+    for (int i = 0; i < data_length_; i++) {
+      data_[i] |= other.data_[i];
+    }
+  }
+
+  bool UnionIsChanged(const BitVector& other) {
+    DCHECK(other.length() == length());
+    bool changed = false;
+    for (int i = 0; i < data_length_; i++) {
+      uintptr_t old_data = data_[i];
+      data_[i] |= other.data_[i];
+      if (data_[i] != old_data) changed = true;
+    }
+    return changed;
+  }
+
+  void Intersect(const BitVector& other) {
+    DCHECK(other.length() == length());
+    for (int i = 0; i < data_length_; i++) {
+      data_[i] &= other.data_[i];
+    }
+  }
+
+  bool IntersectIsChanged(const BitVector& other) {
+    DCHECK(other.length() == length());
+    bool changed = false;
+    for (int i = 0; i < data_length_; i++) {
+      uintptr_t old_data = data_[i];
+      data_[i] &= other.data_[i];
+      if (data_[i] != old_data) changed = true;
+    }
+    return changed;
+  }
+
+  void Subtract(const BitVector& other) {
+    DCHECK(other.length() == length());
+    for (int i = 0; i < data_length_; i++) {
+      data_[i] &= ~other.data_[i];
+    }
+  }
+
+  void Clear() {
+    for (int i = 0; i < data_length_; i++) {
+      data_[i] = 0;
+    }
+  }
+
+  bool IsEmpty() const {
+    for (int i = 0; i < data_length_; i++) {
+      if (data_[i] != 0) return false;
+    }
+    return true;
+  }
+
+  bool Equals(const BitVector& other) {
+    for (int i = 0; i < data_length_; i++) {
+      if (data_[i] != other.data_[i]) return false;
+    }
+    return true;
+  }
+
+  int Count() const;
+
+  int length() const { return length_; }
+
+#ifdef DEBUG
+  void Print();
+#endif
+
+ private:
+  const int length_;
+  const int data_length_;
+  uintptr_t* const data_;
+
+  DISALLOW_COPY_AND_ASSIGN(BitVector);
+};
+
+
+class GrowableBitVector BASE_EMBEDDED {
+ public:
+  class Iterator BASE_EMBEDDED {
+   public:
+    Iterator(const GrowableBitVector* target, Zone* zone)
+        : it_(target->bits_ == NULL ? new (zone) BitVector(1, zone)
+                                    : target->bits_) {}
+    bool Done() const { return it_.Done(); }
+    void Advance() { it_.Advance(); }
+    int Current() const { return it_.Current(); }
+
+   private:
+    BitVector::Iterator it_;
+  };
+
+  GrowableBitVector() : bits_(NULL) {}
+  GrowableBitVector(int length, Zone* zone)
+      : bits_(new (zone) BitVector(length, zone)) {}
+
+  bool Contains(int value) const {
+    if (!InBitsRange(value)) return false;
+    return bits_->Contains(value);
+  }
+
+  void Add(int value, Zone* zone) {
+    EnsureCapacity(value, zone);
+    bits_->Add(value);
+  }
+
+  void Union(const GrowableBitVector& other, Zone* zone) {
+    for (Iterator it(&other, zone); !it.Done(); it.Advance()) {
+      Add(it.Current(), zone);
+    }
+  }
+
+  void Clear() {
+    if (bits_ != NULL) bits_->Clear();
+  }
+
+ private:
+  static const int kInitialLength = 1024;
+
+  bool InBitsRange(int value) const {
+    return bits_ != NULL && bits_->length() > value;
+  }
+
+  void EnsureCapacity(int value, Zone* zone) {
+    if (InBitsRange(value)) return;
+    int new_length = bits_ == NULL ? kInitialLength : bits_->length();
+    while (new_length <= value) new_length *= 2;
+    BitVector* new_bits = new (zone) BitVector(new_length, zone);
+    if (bits_ != NULL) new_bits->CopyFrom(*bits_);
+    bits_ = new_bits;
+  }
+
+  BitVector* bits_;
+};
+
+}  // namespace internal
+}  // namespace v8
+
+#endif  // V8_DATAFLOW_H_