Ben Murdoch | 257744e | 2011-11-30 15:57:28 +0000 | [diff] [blame] | 1 | // Copyright 2011 the V8 project authors. All rights reserved. |
Ben Murdoch | b0fe162 | 2011-05-05 13:52:32 +0100 | [diff] [blame] | 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_LITHIUM_ALLOCATOR_H_ |
| 29 | #define V8_LITHIUM_ALLOCATOR_H_ |
| 30 | |
| 31 | #include "v8.h" |
| 32 | |
Ben Murdoch | 257744e | 2011-11-30 15:57:28 +0000 | [diff] [blame] | 33 | #include "allocation.h" |
Steve Block | 1e0659c | 2011-05-24 12:43:12 +0100 | [diff] [blame] | 34 | #include "lithium.h" |
Ben Murdoch | b0fe162 | 2011-05-05 13:52:32 +0100 | [diff] [blame] | 35 | #include "zone.h" |
| 36 | |
| 37 | namespace v8 { |
| 38 | namespace internal { |
| 39 | |
| 40 | // Forward declarations. |
| 41 | class HBasicBlock; |
| 42 | class HGraph; |
| 43 | class HInstruction; |
| 44 | class HPhi; |
| 45 | class HTracer; |
| 46 | class HValue; |
| 47 | class BitVector; |
| 48 | class StringStream; |
| 49 | |
| 50 | class LArgument; |
| 51 | class LChunk; |
Steve Block | 1e0659c | 2011-05-24 12:43:12 +0100 | [diff] [blame] | 52 | class LOperand; |
| 53 | class LUnallocated; |
Ben Murdoch | b0fe162 | 2011-05-05 13:52:32 +0100 | [diff] [blame] | 54 | class LConstantOperand; |
| 55 | class LGap; |
Ben Murdoch | b0fe162 | 2011-05-05 13:52:32 +0100 | [diff] [blame] | 56 | class LParallelMove; |
| 57 | class LPointerMap; |
| 58 | class LStackSlot; |
| 59 | class LRegister; |
| 60 | |
| 61 | |
| 62 | // This class represents a single point of a LOperand's lifetime. |
| 63 | // For each lithium instruction there are exactly two lifetime positions: |
| 64 | // the beginning and the end of the instruction. Lifetime positions for |
| 65 | // different lithium instructions are disjoint. |
| 66 | class LifetimePosition { |
| 67 | public: |
| 68 | // Return the lifetime position that corresponds to the beginning of |
| 69 | // the instruction with the given index. |
| 70 | static LifetimePosition FromInstructionIndex(int index) { |
| 71 | return LifetimePosition(index * kStep); |
| 72 | } |
| 73 | |
| 74 | // Returns a numeric representation of this lifetime position. |
| 75 | int Value() const { |
| 76 | return value_; |
| 77 | } |
| 78 | |
| 79 | // Returns the index of the instruction to which this lifetime position |
| 80 | // corresponds. |
| 81 | int InstructionIndex() const { |
| 82 | ASSERT(IsValid()); |
| 83 | return value_ / kStep; |
| 84 | } |
| 85 | |
| 86 | // Returns true if this lifetime position corresponds to the instruction |
| 87 | // start. |
| 88 | bool IsInstructionStart() const { |
| 89 | return (value_ & (kStep - 1)) == 0; |
| 90 | } |
| 91 | |
| 92 | // Returns the lifetime position for the start of the instruction which |
| 93 | // corresponds to this lifetime position. |
| 94 | LifetimePosition InstructionStart() const { |
| 95 | ASSERT(IsValid()); |
| 96 | return LifetimePosition(value_ & ~(kStep - 1)); |
| 97 | } |
| 98 | |
| 99 | // Returns the lifetime position for the end of the instruction which |
| 100 | // corresponds to this lifetime position. |
| 101 | LifetimePosition InstructionEnd() const { |
| 102 | ASSERT(IsValid()); |
| 103 | return LifetimePosition(InstructionStart().Value() + kStep/2); |
| 104 | } |
| 105 | |
| 106 | // Returns the lifetime position for the beginning of the next instruction. |
| 107 | LifetimePosition NextInstruction() const { |
| 108 | ASSERT(IsValid()); |
| 109 | return LifetimePosition(InstructionStart().Value() + kStep); |
| 110 | } |
| 111 | |
| 112 | // Returns the lifetime position for the beginning of the previous |
| 113 | // instruction. |
| 114 | LifetimePosition PrevInstruction() const { |
| 115 | ASSERT(IsValid()); |
| 116 | ASSERT(value_ > 1); |
| 117 | return LifetimePosition(InstructionStart().Value() - kStep); |
| 118 | } |
| 119 | |
| 120 | // Constructs the lifetime position which does not correspond to any |
| 121 | // instruction. |
| 122 | LifetimePosition() : value_(-1) {} |
| 123 | |
| 124 | // Returns true if this lifetime positions corrensponds to some |
| 125 | // instruction. |
| 126 | bool IsValid() const { return value_ != -1; } |
| 127 | |
| 128 | static inline LifetimePosition Invalid() { return LifetimePosition(); } |
| 129 | |
| 130 | static inline LifetimePosition MaxPosition() { |
| 131 | // We have to use this kind of getter instead of static member due to |
| 132 | // crash bug in GDB. |
| 133 | return LifetimePosition(kMaxInt); |
| 134 | } |
| 135 | |
| 136 | private: |
| 137 | static const int kStep = 2; |
| 138 | |
| 139 | // Code relies on kStep being a power of two. |
| 140 | STATIC_ASSERT(IS_POWER_OF_TWO(kStep)); |
| 141 | |
| 142 | explicit LifetimePosition(int value) : value_(value) { } |
| 143 | |
| 144 | int value_; |
| 145 | }; |
| 146 | |
| 147 | |
| 148 | enum RegisterKind { |
| 149 | NONE, |
| 150 | GENERAL_REGISTERS, |
| 151 | DOUBLE_REGISTERS |
| 152 | }; |
| 153 | |
| 154 | |
Ben Murdoch | b0fe162 | 2011-05-05 13:52:32 +0100 | [diff] [blame] | 155 | // A register-allocator view of a Lithium instruction. It contains the id of |
| 156 | // the output operand and a list of input operand uses. |
Steve Block | 1e0659c | 2011-05-24 12:43:12 +0100 | [diff] [blame] | 157 | |
| 158 | class LInstruction; |
| 159 | class LEnvironment; |
| 160 | |
| 161 | // Iterator for non-null temp operands. |
| 162 | class TempIterator BASE_EMBEDDED { |
Ben Murdoch | b0fe162 | 2011-05-05 13:52:32 +0100 | [diff] [blame] | 163 | public: |
Steve Block | 1e0659c | 2011-05-24 12:43:12 +0100 | [diff] [blame] | 164 | inline explicit TempIterator(LInstruction* instr); |
Ben Murdoch | 3fb3ca8 | 2011-12-02 17:19:32 +0000 | [diff] [blame^] | 165 | inline bool Done(); |
| 166 | inline LOperand* Current(); |
Steve Block | 1e0659c | 2011-05-24 12:43:12 +0100 | [diff] [blame] | 167 | inline void Advance(); |
Ben Murdoch | 086aeea | 2011-05-13 15:57:08 +0100 | [diff] [blame] | 168 | |
Ben Murdoch | b0fe162 | 2011-05-05 13:52:32 +0100 | [diff] [blame] | 169 | private: |
Ben Murdoch | 3fb3ca8 | 2011-12-02 17:19:32 +0000 | [diff] [blame^] | 170 | inline void SkipUninteresting(); |
Steve Block | 1e0659c | 2011-05-24 12:43:12 +0100 | [diff] [blame] | 171 | LInstruction* instr_; |
| 172 | int limit_; |
| 173 | int current_; |
Ben Murdoch | b0fe162 | 2011-05-05 13:52:32 +0100 | [diff] [blame] | 174 | }; |
| 175 | |
Steve Block | 1e0659c | 2011-05-24 12:43:12 +0100 | [diff] [blame] | 176 | |
| 177 | // Iterator for non-constant input operands. |
| 178 | class InputIterator BASE_EMBEDDED { |
| 179 | public: |
| 180 | inline explicit InputIterator(LInstruction* instr); |
Ben Murdoch | 3fb3ca8 | 2011-12-02 17:19:32 +0000 | [diff] [blame^] | 181 | inline bool Done(); |
| 182 | inline LOperand* Current(); |
Steve Block | 1e0659c | 2011-05-24 12:43:12 +0100 | [diff] [blame] | 183 | inline void Advance(); |
| 184 | |
| 185 | private: |
Ben Murdoch | 3fb3ca8 | 2011-12-02 17:19:32 +0000 | [diff] [blame^] | 186 | inline void SkipUninteresting(); |
Steve Block | 1e0659c | 2011-05-24 12:43:12 +0100 | [diff] [blame] | 187 | LInstruction* instr_; |
| 188 | int limit_; |
| 189 | int current_; |
| 190 | }; |
| 191 | |
| 192 | |
| 193 | class UseIterator BASE_EMBEDDED { |
| 194 | public: |
| 195 | inline explicit UseIterator(LInstruction* instr); |
Ben Murdoch | 3fb3ca8 | 2011-12-02 17:19:32 +0000 | [diff] [blame^] | 196 | inline bool Done(); |
| 197 | inline LOperand* Current(); |
Steve Block | 1e0659c | 2011-05-24 12:43:12 +0100 | [diff] [blame] | 198 | inline void Advance(); |
| 199 | |
| 200 | private: |
| 201 | InputIterator input_iterator_; |
| 202 | DeepIterator env_iterator_; |
| 203 | }; |
| 204 | |
| 205 | |
Ben Murdoch | b0fe162 | 2011-05-05 13:52:32 +0100 | [diff] [blame] | 206 | // Representation of the non-empty interval [start,end[. |
| 207 | class UseInterval: public ZoneObject { |
| 208 | public: |
| 209 | UseInterval(LifetimePosition start, LifetimePosition end) |
| 210 | : start_(start), end_(end), next_(NULL) { |
| 211 | ASSERT(start.Value() < end.Value()); |
| 212 | } |
| 213 | |
| 214 | LifetimePosition start() const { return start_; } |
| 215 | LifetimePosition end() const { return end_; } |
| 216 | UseInterval* next() const { return next_; } |
| 217 | |
| 218 | // Split this interval at the given position without effecting the |
| 219 | // live range that owns it. The interval must contain the position. |
| 220 | void SplitAt(LifetimePosition pos); |
| 221 | |
| 222 | // If this interval intersects with other return smallest position |
| 223 | // that belongs to both of them. |
| 224 | LifetimePosition Intersect(const UseInterval* other) const { |
| 225 | if (other->start().Value() < start_.Value()) return other->Intersect(this); |
| 226 | if (other->start().Value() < end_.Value()) return other->start(); |
| 227 | return LifetimePosition::Invalid(); |
| 228 | } |
| 229 | |
| 230 | bool Contains(LifetimePosition point) const { |
| 231 | return start_.Value() <= point.Value() && point.Value() < end_.Value(); |
| 232 | } |
| 233 | |
| 234 | private: |
| 235 | void set_start(LifetimePosition start) { start_ = start; } |
| 236 | void set_next(UseInterval* next) { next_ = next; } |
| 237 | |
| 238 | LifetimePosition start_; |
| 239 | LifetimePosition end_; |
| 240 | UseInterval* next_; |
| 241 | |
| 242 | friend class LiveRange; // Assigns to start_. |
| 243 | }; |
| 244 | |
| 245 | // Representation of a use position. |
| 246 | class UsePosition: public ZoneObject { |
| 247 | public: |
Steve Block | 1e0659c | 2011-05-24 12:43:12 +0100 | [diff] [blame] | 248 | UsePosition(LifetimePosition pos, LOperand* operand); |
Ben Murdoch | b0fe162 | 2011-05-05 13:52:32 +0100 | [diff] [blame] | 249 | |
| 250 | LOperand* operand() const { return operand_; } |
| 251 | bool HasOperand() const { return operand_ != NULL; } |
| 252 | |
| 253 | LOperand* hint() const { return hint_; } |
| 254 | void set_hint(LOperand* hint) { hint_ = hint; } |
Steve Block | 1e0659c | 2011-05-24 12:43:12 +0100 | [diff] [blame] | 255 | bool HasHint() const; |
Ben Murdoch | b0fe162 | 2011-05-05 13:52:32 +0100 | [diff] [blame] | 256 | bool RequiresRegister() const; |
| 257 | bool RegisterIsBeneficial() const; |
| 258 | |
| 259 | LifetimePosition pos() const { return pos_; } |
| 260 | UsePosition* next() const { return next_; } |
| 261 | |
| 262 | private: |
| 263 | void set_next(UsePosition* next) { next_ = next; } |
| 264 | |
| 265 | LOperand* operand_; |
| 266 | LOperand* hint_; |
| 267 | LifetimePosition pos_; |
| 268 | UsePosition* next_; |
| 269 | bool requires_reg_; |
| 270 | bool register_beneficial_; |
| 271 | |
| 272 | friend class LiveRange; |
| 273 | }; |
| 274 | |
| 275 | // Representation of SSA values' live ranges as a collection of (continuous) |
| 276 | // intervals over the instruction ordering. |
| 277 | class LiveRange: public ZoneObject { |
| 278 | public: |
| 279 | static const int kInvalidAssignment = 0x7fffffff; |
| 280 | |
Steve Block | 1e0659c | 2011-05-24 12:43:12 +0100 | [diff] [blame] | 281 | explicit LiveRange(int id); |
Ben Murdoch | b0fe162 | 2011-05-05 13:52:32 +0100 | [diff] [blame] | 282 | |
| 283 | UseInterval* first_interval() const { return first_interval_; } |
| 284 | UsePosition* first_pos() const { return first_pos_; } |
| 285 | LiveRange* parent() const { return parent_; } |
| 286 | LiveRange* TopLevel() { return (parent_ == NULL) ? this : parent_; } |
| 287 | LiveRange* next() const { return next_; } |
| 288 | bool IsChild() const { return parent() != NULL; } |
Ben Murdoch | b0fe162 | 2011-05-05 13:52:32 +0100 | [diff] [blame] | 289 | int id() const { return id_; } |
| 290 | bool IsFixed() const { return id_ < 0; } |
| 291 | bool IsEmpty() const { return first_interval() == NULL; } |
| 292 | LOperand* CreateAssignedOperand(); |
| 293 | int assigned_register() const { return assigned_register_; } |
| 294 | int spill_start_index() const { return spill_start_index_; } |
Steve Block | 1e0659c | 2011-05-24 12:43:12 +0100 | [diff] [blame] | 295 | void set_assigned_register(int reg, RegisterKind register_kind); |
| 296 | void MakeSpilled(); |
Ben Murdoch | b0fe162 | 2011-05-05 13:52:32 +0100 | [diff] [blame] | 297 | |
| 298 | // Returns use position in this live range that follows both start |
| 299 | // and last processed use position. |
| 300 | // Modifies internal state of live range! |
| 301 | UsePosition* NextUsePosition(LifetimePosition start); |
| 302 | |
| 303 | // Returns use position for which register is required in this live |
| 304 | // range and which follows both start and last processed use position |
| 305 | // Modifies internal state of live range! |
| 306 | UsePosition* NextRegisterPosition(LifetimePosition start); |
| 307 | |
| 308 | // Returns use position for which register is beneficial in this live |
| 309 | // range and which follows both start and last processed use position |
| 310 | // Modifies internal state of live range! |
| 311 | UsePosition* NextUsePositionRegisterIsBeneficial(LifetimePosition start); |
| 312 | |
| 313 | // Can this live range be spilled at this position. |
| 314 | bool CanBeSpilled(LifetimePosition pos); |
| 315 | |
| 316 | // Split this live range at the given position which must follow the start of |
| 317 | // the range. |
| 318 | // All uses following the given position will be moved from this |
| 319 | // live range to the result live range. |
| 320 | void SplitAt(LifetimePosition position, LiveRange* result); |
| 321 | |
| 322 | bool IsDouble() const { return assigned_register_kind_ == DOUBLE_REGISTERS; } |
| 323 | bool HasRegisterAssigned() const { |
| 324 | return assigned_register_ != kInvalidAssignment; |
| 325 | } |
| 326 | bool IsSpilled() const { return spilled_; } |
| 327 | UsePosition* FirstPosWithHint() const; |
| 328 | |
| 329 | LOperand* FirstHint() const { |
| 330 | UsePosition* pos = FirstPosWithHint(); |
| 331 | if (pos != NULL) return pos->hint(); |
| 332 | return NULL; |
| 333 | } |
| 334 | |
| 335 | LifetimePosition Start() const { |
| 336 | ASSERT(!IsEmpty()); |
| 337 | return first_interval()->start(); |
| 338 | } |
| 339 | |
| 340 | LifetimePosition End() const { |
| 341 | ASSERT(!IsEmpty()); |
| 342 | return last_interval_->end(); |
| 343 | } |
| 344 | |
Steve Block | 1e0659c | 2011-05-24 12:43:12 +0100 | [diff] [blame] | 345 | bool HasAllocatedSpillOperand() const; |
Ben Murdoch | b0fe162 | 2011-05-05 13:52:32 +0100 | [diff] [blame] | 346 | LOperand* GetSpillOperand() const { return spill_operand_; } |
Steve Block | 1e0659c | 2011-05-24 12:43:12 +0100 | [diff] [blame] | 347 | void SetSpillOperand(LOperand* operand); |
Ben Murdoch | b0fe162 | 2011-05-05 13:52:32 +0100 | [diff] [blame] | 348 | |
| 349 | void SetSpillStartIndex(int start) { |
| 350 | spill_start_index_ = Min(start, spill_start_index_); |
| 351 | } |
| 352 | |
| 353 | bool ShouldBeAllocatedBefore(const LiveRange* other) const; |
| 354 | bool CanCover(LifetimePosition position) const; |
| 355 | bool Covers(LifetimePosition position); |
| 356 | LifetimePosition FirstIntersection(LiveRange* other); |
| 357 | |
Ben Murdoch | b0fe162 | 2011-05-05 13:52:32 +0100 | [diff] [blame] | 358 | // Add a new interval or a new use position to this live range. |
| 359 | void EnsureInterval(LifetimePosition start, LifetimePosition end); |
| 360 | void AddUseInterval(LifetimePosition start, LifetimePosition end); |
| 361 | UsePosition* AddUsePosition(LifetimePosition pos, LOperand* operand); |
Ben Murdoch | b0fe162 | 2011-05-05 13:52:32 +0100 | [diff] [blame] | 362 | |
| 363 | // Shorten the most recently added interval by setting a new start. |
| 364 | void ShortenTo(LifetimePosition start); |
| 365 | |
| 366 | #ifdef DEBUG |
| 367 | // True if target overlaps an existing interval. |
| 368 | bool HasOverlap(UseInterval* target) const; |
| 369 | void Verify() const; |
| 370 | #endif |
| 371 | |
| 372 | private: |
| 373 | void ConvertOperands(); |
| 374 | UseInterval* FirstSearchIntervalForPosition(LifetimePosition position) const; |
| 375 | void AdvanceLastProcessedMarker(UseInterval* to_start_of, |
| 376 | LifetimePosition but_not_past) const; |
| 377 | |
| 378 | int id_; |
| 379 | bool spilled_; |
| 380 | int assigned_register_; |
| 381 | RegisterKind assigned_register_kind_; |
| 382 | UseInterval* last_interval_; |
| 383 | UseInterval* first_interval_; |
| 384 | UsePosition* first_pos_; |
| 385 | LiveRange* parent_; |
| 386 | LiveRange* next_; |
| 387 | // This is used as a cache, it doesn't affect correctness. |
| 388 | mutable UseInterval* current_interval_; |
| 389 | UsePosition* last_processed_use_; |
| 390 | LOperand* spill_operand_; |
| 391 | int spill_start_index_; |
| 392 | }; |
| 393 | |
| 394 | |
Steve Block | 9fac840 | 2011-05-12 15:51:54 +0100 | [diff] [blame] | 395 | class GrowableBitVector BASE_EMBEDDED { |
| 396 | public: |
| 397 | GrowableBitVector() : bits_(NULL) { } |
| 398 | |
| 399 | bool Contains(int value) const { |
| 400 | if (!InBitsRange(value)) return false; |
| 401 | return bits_->Contains(value); |
| 402 | } |
| 403 | |
| 404 | void Add(int value) { |
| 405 | EnsureCapacity(value); |
| 406 | bits_->Add(value); |
| 407 | } |
| 408 | |
| 409 | private: |
| 410 | static const int kInitialLength = 1024; |
| 411 | |
| 412 | bool InBitsRange(int value) const { |
| 413 | return bits_ != NULL && bits_->length() > value; |
| 414 | } |
| 415 | |
| 416 | void EnsureCapacity(int value) { |
| 417 | if (InBitsRange(value)) return; |
| 418 | int new_length = bits_ == NULL ? kInitialLength : bits_->length(); |
| 419 | while (new_length <= value) new_length *= 2; |
| 420 | BitVector* new_bits = new BitVector(new_length); |
| 421 | if (bits_ != NULL) new_bits->CopyFrom(*bits_); |
| 422 | bits_ = new_bits; |
| 423 | } |
| 424 | |
| 425 | BitVector* bits_; |
| 426 | }; |
| 427 | |
| 428 | |
Ben Murdoch | b0fe162 | 2011-05-05 13:52:32 +0100 | [diff] [blame] | 429 | class LAllocator BASE_EMBEDDED { |
| 430 | public: |
Steve Block | 44f0eee | 2011-05-26 01:26:41 +0100 | [diff] [blame] | 431 | LAllocator(int first_virtual_register, HGraph* graph); |
Ben Murdoch | b0fe162 | 2011-05-05 13:52:32 +0100 | [diff] [blame] | 432 | |
Ben Murdoch | b0fe162 | 2011-05-05 13:52:32 +0100 | [diff] [blame] | 433 | static void TraceAlloc(const char* msg, ...); |
| 434 | |
| 435 | // Lithium translation support. |
| 436 | // Record a use of an input operand in the current instruction. |
| 437 | void RecordUse(HValue* value, LUnallocated* operand); |
| 438 | // Record the definition of the output operand. |
| 439 | void RecordDefinition(HInstruction* instr, LUnallocated* operand); |
| 440 | // Record a temporary operand. |
| 441 | void RecordTemporary(LUnallocated* operand); |
| 442 | |
Ben Murdoch | b0fe162 | 2011-05-05 13:52:32 +0100 | [diff] [blame] | 443 | // Checks whether the value of a given virtual register is tagged. |
| 444 | bool HasTaggedValue(int virtual_register) const; |
| 445 | |
| 446 | // Returns the register kind required by the given virtual register. |
| 447 | RegisterKind RequiredRegisterKind(int virtual_register) const; |
| 448 | |
Ben Murdoch | b0fe162 | 2011-05-05 13:52:32 +0100 | [diff] [blame] | 449 | // Control max function size. |
| 450 | static int max_initial_value_ids(); |
| 451 | |
| 452 | void Allocate(LChunk* chunk); |
| 453 | |
| 454 | const ZoneList<LiveRange*>* live_ranges() const { return &live_ranges_; } |
Steve Block | 44f0eee | 2011-05-26 01:26:41 +0100 | [diff] [blame] | 455 | const Vector<LiveRange*>* fixed_live_ranges() const { |
Ben Murdoch | b0fe162 | 2011-05-05 13:52:32 +0100 | [diff] [blame] | 456 | return &fixed_live_ranges_; |
| 457 | } |
Steve Block | 44f0eee | 2011-05-26 01:26:41 +0100 | [diff] [blame] | 458 | const Vector<LiveRange*>* fixed_double_live_ranges() const { |
Ben Murdoch | b0fe162 | 2011-05-05 13:52:32 +0100 | [diff] [blame] | 459 | return &fixed_double_live_ranges_; |
| 460 | } |
| 461 | |
| 462 | LChunk* chunk() const { return chunk_; } |
| 463 | HGraph* graph() const { return graph_; } |
| 464 | |
| 465 | void MarkAsOsrEntry() { |
| 466 | // There can be only one. |
| 467 | ASSERT(!has_osr_entry_); |
| 468 | // Simply set a flag to find and process instruction later. |
| 469 | has_osr_entry_ = true; |
| 470 | } |
| 471 | |
| 472 | #ifdef DEBUG |
| 473 | void Verify() const; |
| 474 | #endif |
| 475 | |
| 476 | private: |
| 477 | void MeetRegisterConstraints(); |
| 478 | void ResolvePhis(); |
| 479 | void BuildLiveRanges(); |
| 480 | void AllocateGeneralRegisters(); |
| 481 | void AllocateDoubleRegisters(); |
| 482 | void ConnectRanges(); |
| 483 | void ResolveControlFlow(); |
| 484 | void PopulatePointerMaps(); |
| 485 | void ProcessOsrEntry(); |
| 486 | void AllocateRegisters(); |
| 487 | bool CanEagerlyResolveControlFlow(HBasicBlock* block) const; |
| 488 | inline bool SafePointsAreInOrder() const; |
| 489 | |
| 490 | // Liveness analysis support. |
| 491 | void InitializeLivenessAnalysis(); |
| 492 | BitVector* ComputeLiveOut(HBasicBlock* block); |
| 493 | void AddInitialIntervals(HBasicBlock* block, BitVector* live_out); |
| 494 | void ProcessInstructions(HBasicBlock* block, BitVector* live); |
| 495 | void MeetRegisterConstraints(HBasicBlock* block); |
Steve Block | 1e0659c | 2011-05-24 12:43:12 +0100 | [diff] [blame] | 496 | void MeetConstraintsBetween(LInstruction* first, |
| 497 | LInstruction* second, |
Ben Murdoch | b0fe162 | 2011-05-05 13:52:32 +0100 | [diff] [blame] | 498 | int gap_index); |
| 499 | void ResolvePhis(HBasicBlock* block); |
| 500 | |
| 501 | // Helper methods for building intervals. |
| 502 | LOperand* AllocateFixed(LUnallocated* operand, int pos, bool is_tagged); |
| 503 | LiveRange* LiveRangeFor(LOperand* operand); |
| 504 | void Define(LifetimePosition position, LOperand* operand, LOperand* hint); |
| 505 | void Use(LifetimePosition block_start, |
| 506 | LifetimePosition position, |
| 507 | LOperand* operand, |
| 508 | LOperand* hint); |
| 509 | void AddConstraintsGapMove(int index, LOperand* from, LOperand* to); |
| 510 | |
| 511 | // Helper methods for updating the life range lists. |
| 512 | void AddToActive(LiveRange* range); |
| 513 | void AddToInactive(LiveRange* range); |
| 514 | void AddToUnhandledSorted(LiveRange* range); |
| 515 | void AddToUnhandledUnsorted(LiveRange* range); |
| 516 | void SortUnhandled(); |
| 517 | bool UnhandledIsSorted(); |
| 518 | void ActiveToHandled(LiveRange* range); |
| 519 | void ActiveToInactive(LiveRange* range); |
| 520 | void InactiveToHandled(LiveRange* range); |
| 521 | void InactiveToActive(LiveRange* range); |
| 522 | void FreeSpillSlot(LiveRange* range); |
| 523 | LOperand* TryReuseSpillSlot(LiveRange* range); |
| 524 | |
| 525 | // Helper methods for allocating registers. |
| 526 | bool TryAllocateFreeReg(LiveRange* range); |
| 527 | void AllocateBlockedReg(LiveRange* range); |
| 528 | |
| 529 | // Live range splitting helpers. |
| 530 | |
| 531 | // Split the given range at the given position. |
| 532 | // If range starts at or after the given position then the |
| 533 | // original range is returned. |
| 534 | // Otherwise returns the live range that starts at pos and contains |
| 535 | // all uses from the original range that follow pos. Uses at pos will |
| 536 | // still be owned by the original range after splitting. |
| 537 | LiveRange* SplitAt(LiveRange* range, LifetimePosition pos); |
| 538 | |
| 539 | // Split the given range in a position from the interval [start, end]. |
| 540 | LiveRange* SplitBetween(LiveRange* range, |
| 541 | LifetimePosition start, |
| 542 | LifetimePosition end); |
| 543 | |
| 544 | // Find a lifetime position in the interval [start, end] which |
| 545 | // is optimal for splitting: it is either header of the outermost |
| 546 | // loop covered by this interval or the latest possible position. |
| 547 | LifetimePosition FindOptimalSplitPos(LifetimePosition start, |
| 548 | LifetimePosition end); |
| 549 | |
| 550 | // Spill the given life range after position pos. |
| 551 | void SpillAfter(LiveRange* range, LifetimePosition pos); |
| 552 | |
| 553 | // Spill the given life range after position start and up to position end. |
| 554 | void SpillBetween(LiveRange* range, |
| 555 | LifetimePosition start, |
| 556 | LifetimePosition end); |
| 557 | |
| 558 | void SplitAndSpillIntersecting(LiveRange* range); |
| 559 | |
| 560 | void Spill(LiveRange* range); |
| 561 | bool IsBlockBoundary(LifetimePosition pos); |
Ben Murdoch | b0fe162 | 2011-05-05 13:52:32 +0100 | [diff] [blame] | 562 | |
| 563 | // Helper methods for resolving control flow. |
| 564 | void ResolveControlFlow(LiveRange* range, |
| 565 | HBasicBlock* block, |
| 566 | HBasicBlock* pred); |
| 567 | |
| 568 | // Return parallel move that should be used to connect ranges split at the |
| 569 | // given position. |
| 570 | LParallelMove* GetConnectingParallelMove(LifetimePosition pos); |
| 571 | |
| 572 | // Return the block which contains give lifetime position. |
| 573 | HBasicBlock* GetBlock(LifetimePosition pos); |
| 574 | |
Ben Murdoch | b0fe162 | 2011-05-05 13:52:32 +0100 | [diff] [blame] | 575 | // Helper methods for the fixed registers. |
| 576 | int RegisterCount() const; |
| 577 | static int FixedLiveRangeID(int index) { return -index - 1; } |
| 578 | static int FixedDoubleLiveRangeID(int index); |
| 579 | LiveRange* FixedLiveRangeFor(int index); |
| 580 | LiveRange* FixedDoubleLiveRangeFor(int index); |
| 581 | LiveRange* LiveRangeFor(int index); |
| 582 | HPhi* LookupPhi(LOperand* operand) const; |
Steve Block | 1e0659c | 2011-05-24 12:43:12 +0100 | [diff] [blame] | 583 | LGap* GetLastGap(HBasicBlock* block); |
Ben Murdoch | b0fe162 | 2011-05-05 13:52:32 +0100 | [diff] [blame] | 584 | |
| 585 | const char* RegisterName(int allocation_index); |
| 586 | |
Steve Block | 1e0659c | 2011-05-24 12:43:12 +0100 | [diff] [blame] | 587 | inline bool IsGapAt(int index); |
Ben Murdoch | b0fe162 | 2011-05-05 13:52:32 +0100 | [diff] [blame] | 588 | |
Steve Block | 1e0659c | 2011-05-24 12:43:12 +0100 | [diff] [blame] | 589 | inline LInstruction* InstructionAt(int index); |
| 590 | |
| 591 | inline LGap* GapAt(int index); |
| 592 | |
| 593 | LChunk* chunk_; |
Ben Murdoch | b0fe162 | 2011-05-05 13:52:32 +0100 | [diff] [blame] | 594 | |
| 595 | // During liveness analysis keep a mapping from block id to live_in sets |
| 596 | // for blocks already analyzed. |
| 597 | ZoneList<BitVector*> live_in_sets_; |
| 598 | |
| 599 | // Liveness analysis results. |
| 600 | ZoneList<LiveRange*> live_ranges_; |
| 601 | |
| 602 | // Lists of live ranges |
Steve Block | 44f0eee | 2011-05-26 01:26:41 +0100 | [diff] [blame] | 603 | EmbeddedVector<LiveRange*, Register::kNumAllocatableRegisters> |
| 604 | fixed_live_ranges_; |
| 605 | EmbeddedVector<LiveRange*, DoubleRegister::kNumAllocatableRegisters> |
| 606 | fixed_double_live_ranges_; |
Ben Murdoch | b0fe162 | 2011-05-05 13:52:32 +0100 | [diff] [blame] | 607 | ZoneList<LiveRange*> unhandled_live_ranges_; |
| 608 | ZoneList<LiveRange*> active_live_ranges_; |
| 609 | ZoneList<LiveRange*> inactive_live_ranges_; |
| 610 | ZoneList<LiveRange*> reusable_slots_; |
| 611 | |
| 612 | // Next virtual register number to be assigned to temporaries. |
| 613 | int next_virtual_register_; |
Steve Block | 9fac840 | 2011-05-12 15:51:54 +0100 | [diff] [blame] | 614 | int first_artificial_register_; |
| 615 | GrowableBitVector double_artificial_registers_; |
Ben Murdoch | b0fe162 | 2011-05-05 13:52:32 +0100 | [diff] [blame] | 616 | |
| 617 | RegisterKind mode_; |
| 618 | int num_registers_; |
| 619 | |
| 620 | HGraph* graph_; |
| 621 | |
| 622 | bool has_osr_entry_; |
| 623 | |
| 624 | DISALLOW_COPY_AND_ASSIGN(LAllocator); |
| 625 | }; |
| 626 | |
| 627 | |
| 628 | } } // namespace v8::internal |
| 629 | |
| 630 | #endif // V8_LITHIUM_ALLOCATOR_H_ |