1 // Copyright 2012 the V8 project authors. All rights reserved. 2 // Redistribution and use in source and binary forms, with or without 3 // modification, are permitted provided that the following conditions are 4 // met: 5 // 6 // * Redistributions of source code must retain the above copyright 7 // notice, this list of conditions and the following disclaimer. 8 // * Redistributions in binary form must reproduce the above 9 // copyright notice, this list of conditions and the following 10 // disclaimer in the documentation and/or other materials provided 11 // with the distribution. 12 // * Neither the name of Google Inc. nor the names of its 13 // contributors may be used to endorse or promote products derived 14 // from this software without specific prior written permission. 15 // 16 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 17 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 18 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 19 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 20 // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 21 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 22 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 23 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 24 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 25 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 26 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 27 28 #ifndef V8_DATAFLOW_H_ 29 #define V8_DATAFLOW_H_ 30 31 #include "v8.h" 32 33 #include "allocation.h" 34 #include "ast.h" 35 #include "compiler.h" 36 #include "zone-inl.h" 37 38 namespace v8 { 39 namespace internal { 40 41 class BitVector: public ZoneObject { 42 public: 43 // Iterator for the elements of this BitVector. 44 class Iterator BASE_EMBEDDED { 45 public: Iterator(BitVector * target)46 explicit Iterator(BitVector* target) 47 : target_(target), 48 current_index_(0), 49 current_value_(target->data_[0]), 50 current_(-1) { 51 ASSERT(target->data_length_ > 0); 52 Advance(); 53 } ~Iterator()54 ~Iterator() { } 55 Done()56 bool Done() const { return current_index_ >= target_->data_length_; } 57 void Advance(); 58 Current()59 int Current() const { 60 ASSERT(!Done()); 61 return current_; 62 } 63 64 private: SkipZeroBytes(uint32_t val)65 uint32_t SkipZeroBytes(uint32_t val) { 66 while ((val & 0xFF) == 0) { 67 val >>= 8; 68 current_ += 8; 69 } 70 return val; 71 } SkipZeroBits(uint32_t val)72 uint32_t SkipZeroBits(uint32_t val) { 73 while ((val & 0x1) == 0) { 74 val >>= 1; 75 current_++; 76 } 77 return val; 78 } 79 80 BitVector* target_; 81 int current_index_; 82 uint32_t current_value_; 83 int current_; 84 85 friend class BitVector; 86 }; 87 BitVector(int length,Zone * zone)88 BitVector(int length, Zone* zone) 89 : length_(length), 90 data_length_(SizeFor(length)), 91 data_(zone->NewArray<uint32_t>(data_length_)) { 92 ASSERT(length > 0); 93 Clear(); 94 } 95 BitVector(const BitVector & other,Zone * zone)96 BitVector(const BitVector& other, Zone* zone) 97 : length_(other.length()), 98 data_length_(SizeFor(length_)), 99 data_(zone->NewArray<uint32_t>(data_length_)) { 100 CopyFrom(other); 101 } 102 SizeFor(int length)103 static int SizeFor(int length) { 104 return 1 + ((length - 1) / 32); 105 } 106 107 BitVector& operator=(const BitVector& rhs) { 108 if (this != &rhs) CopyFrom(rhs); 109 return *this; 110 } 111 CopyFrom(const BitVector & other)112 void CopyFrom(const BitVector& other) { 113 ASSERT(other.length() <= length()); 114 for (int i = 0; i < other.data_length_; i++) { 115 data_[i] = other.data_[i]; 116 } 117 for (int i = other.data_length_; i < data_length_; i++) { 118 data_[i] = 0; 119 } 120 } 121 Contains(int i)122 bool Contains(int i) const { 123 ASSERT(i >= 0 && i < length()); 124 uint32_t block = data_[i / 32]; 125 return (block & (1U << (i % 32))) != 0; 126 } 127 Add(int i)128 void Add(int i) { 129 ASSERT(i >= 0 && i < length()); 130 data_[i / 32] |= (1U << (i % 32)); 131 } 132 Remove(int i)133 void Remove(int i) { 134 ASSERT(i >= 0 && i < length()); 135 data_[i / 32] &= ~(1U << (i % 32)); 136 } 137 Union(const BitVector & other)138 void Union(const BitVector& other) { 139 ASSERT(other.length() == length()); 140 for (int i = 0; i < data_length_; i++) { 141 data_[i] |= other.data_[i]; 142 } 143 } 144 UnionIsChanged(const BitVector & other)145 bool UnionIsChanged(const BitVector& other) { 146 ASSERT(other.length() == length()); 147 bool changed = false; 148 for (int i = 0; i < data_length_; i++) { 149 uint32_t old_data = data_[i]; 150 data_[i] |= other.data_[i]; 151 if (data_[i] != old_data) changed = true; 152 } 153 return changed; 154 } 155 Intersect(const BitVector & other)156 void Intersect(const BitVector& other) { 157 ASSERT(other.length() == length()); 158 for (int i = 0; i < data_length_; i++) { 159 data_[i] &= other.data_[i]; 160 } 161 } 162 Subtract(const BitVector & other)163 void Subtract(const BitVector& other) { 164 ASSERT(other.length() == length()); 165 for (int i = 0; i < data_length_; i++) { 166 data_[i] &= ~other.data_[i]; 167 } 168 } 169 Clear()170 void Clear() { 171 for (int i = 0; i < data_length_; i++) { 172 data_[i] = 0; 173 } 174 } 175 IsEmpty()176 bool IsEmpty() const { 177 for (int i = 0; i < data_length_; i++) { 178 if (data_[i] != 0) return false; 179 } 180 return true; 181 } 182 Equals(const BitVector & other)183 bool Equals(const BitVector& other) { 184 for (int i = 0; i < data_length_; i++) { 185 if (data_[i] != other.data_[i]) return false; 186 } 187 return true; 188 } 189 length()190 int length() const { return length_; } 191 192 #ifdef DEBUG 193 void Print(); 194 #endif 195 196 private: 197 int length_; 198 int data_length_; 199 uint32_t* data_; 200 }; 201 202 } } // namespace v8::internal 203 204 205 #endif // V8_DATAFLOW_H_ 206