convert BitVector to use pointer size blocks

src/data-flow.h

-// 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:
-    uint32_t SkipZeroBytes(uint32_t val) {
-      while ((val & 0xFF) == 0) {
-        val >>= 8;
-        current_ += 8;
-      }
-      return val;
-    }
-    uint32_t SkipZeroBits(uint32_t val) {
-      while ((val & 0x1) == 0) {
-        val >>= 1;
-        current_++;
-      }
-      return val;
-    }
-
-    BitVector* target_;
-    int current_index_;
-    uint32_t current_value_;
-    int current_;
-
-    friend class BitVector;
-  };
-
-  BitVector(int length, Zone* zone)
-      : length_(length),
-        data_length_(SizeFor(length)),
-        data_(zone->NewArray<uint32_t>(data_length_)) {
-    DCHECK(length > 0);
-    Clear();
-  }
-
-  BitVector(const BitVector& other, Zone* zone)
-      : length_(other.length()),
-        data_length_(SizeFor(length_)),
-        data_(zone->NewArray<uint32_t>(data_length_)) {
-    CopyFrom(other);
-  }
-
-  static int SizeFor(int length) {
-    return 1 + ((length - 1) / 32);
-  }
-
-  BitVector& operator=(const BitVector& rhs) {
-    if (this != &rhs) CopyFrom(rhs);
-    return *this;
-  }
-
-  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());
-    uint32_t block = data_[i / 32];
-    return (block & (1U << (i % 32))) != 0;
-  }
-
-  void Add(int i) {
-    DCHECK(i >= 0 && i < length());
-    data_[i / 32] |= (1U << (i % 32));
-  }
-
-  void Remove(int i) {
-    DCHECK(i >= 0 && i < length());
-    data_[i / 32] &= ~(1U << (i % 32));
-  }
-
-  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++) {
-      uint32_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++) {
-      uint32_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:
-  int length_;
-  int data_length_;
-  uint32_t* data_;
-};
-
-
-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_