Ben Murdoch | b0fe162 | 2011-05-05 13:52:32 +0100 | [diff] [blame^] | 1 | // Copyright 2010 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_DEOPTIMIZER_H_ |
| 29 | #define V8_DEOPTIMIZER_H_ |
| 30 | |
| 31 | #include "v8.h" |
| 32 | |
| 33 | #include "macro-assembler.h" |
| 34 | #include "zone-inl.h" |
| 35 | |
| 36 | |
| 37 | namespace v8 { |
| 38 | namespace internal { |
| 39 | |
| 40 | class FrameDescription; |
| 41 | class TranslationIterator; |
| 42 | class DeoptimizingCodeListNode; |
| 43 | |
| 44 | |
| 45 | class ValueDescription BASE_EMBEDDED { |
| 46 | public: |
| 47 | explicit ValueDescription(int index) : stack_index_(index) { } |
| 48 | int stack_index() const { return stack_index_; } |
| 49 | |
| 50 | private: |
| 51 | // Offset relative to the top of the stack. |
| 52 | int stack_index_; |
| 53 | }; |
| 54 | |
| 55 | |
| 56 | class ValueDescriptionInteger32: public ValueDescription { |
| 57 | public: |
| 58 | ValueDescriptionInteger32(int index, int32_t value) |
| 59 | : ValueDescription(index), int32_value_(value) { } |
| 60 | int32_t int32_value() const { return int32_value_; } |
| 61 | |
| 62 | private: |
| 63 | // Raw value. |
| 64 | int32_t int32_value_; |
| 65 | }; |
| 66 | |
| 67 | |
| 68 | class ValueDescriptionDouble: public ValueDescription { |
| 69 | public: |
| 70 | ValueDescriptionDouble(int index, double value) |
| 71 | : ValueDescription(index), double_value_(value) { } |
| 72 | double double_value() const { return double_value_; } |
| 73 | |
| 74 | private: |
| 75 | // Raw value. |
| 76 | double double_value_; |
| 77 | }; |
| 78 | |
| 79 | |
| 80 | class OptimizedFunctionVisitor BASE_EMBEDDED { |
| 81 | public: |
| 82 | virtual ~OptimizedFunctionVisitor() {} |
| 83 | |
| 84 | // Function which is called before iteration of any optimized functions |
| 85 | // from given global context. |
| 86 | virtual void EnterContext(Context* context) = 0; |
| 87 | |
| 88 | virtual void VisitFunction(JSFunction* function) = 0; |
| 89 | |
| 90 | // Function which is called after iteration of all optimized functions |
| 91 | // from given global context. |
| 92 | virtual void LeaveContext(Context* context) = 0; |
| 93 | }; |
| 94 | |
| 95 | |
| 96 | class Deoptimizer : public Malloced { |
| 97 | public: |
| 98 | enum BailoutType { |
| 99 | EAGER, |
| 100 | LAZY, |
| 101 | OSR |
| 102 | }; |
| 103 | |
| 104 | int output_count() const { return output_count_; } |
| 105 | |
| 106 | static Deoptimizer* New(JSFunction* function, |
| 107 | BailoutType type, |
| 108 | unsigned bailout_id, |
| 109 | Address from, |
| 110 | int fp_to_sp_delta); |
| 111 | static Deoptimizer* Grab(); |
| 112 | |
| 113 | // Deoptimize the function now. Its current optimized code will never be run |
| 114 | // again and any activations of the optimized code will get deoptimized when |
| 115 | // execution returns. |
| 116 | static void DeoptimizeFunction(JSFunction* function); |
| 117 | |
| 118 | // Deoptimize all functions in the heap. |
| 119 | static void DeoptimizeAll(); |
| 120 | |
| 121 | static void DeoptimizeGlobalObject(JSObject* object); |
| 122 | |
| 123 | static void VisitAllOptimizedFunctionsForContext( |
| 124 | Context* context, OptimizedFunctionVisitor* visitor); |
| 125 | |
| 126 | static void VisitAllOptimizedFunctionsForGlobalObject( |
| 127 | JSObject* object, OptimizedFunctionVisitor* visitor); |
| 128 | |
| 129 | static void VisitAllOptimizedFunctions(OptimizedFunctionVisitor* visitor); |
| 130 | |
| 131 | // Given the relocation info of a call to the stack check stub, patch the |
| 132 | // code so as to go unconditionally to the on-stack replacement builtin |
| 133 | // instead. |
| 134 | static void PatchStackCheckCode(RelocInfo* rinfo, Code* replacement_code); |
| 135 | |
| 136 | // Given the relocation info of a call to the on-stack replacement |
| 137 | // builtin, patch the code back to the original stack check code. |
| 138 | static void RevertStackCheckCode(RelocInfo* rinfo, Code* check_code); |
| 139 | |
| 140 | ~Deoptimizer(); |
| 141 | |
| 142 | void InsertHeapNumberValues(int index, JavaScriptFrame* frame); |
| 143 | |
| 144 | static void ComputeOutputFrames(Deoptimizer* deoptimizer); |
| 145 | |
| 146 | static Address GetDeoptimizationEntry(int id, BailoutType type); |
| 147 | static int GetDeoptimizationId(Address addr, BailoutType type); |
| 148 | static unsigned GetOutputInfo(DeoptimizationOutputData* data, |
| 149 | unsigned node_id, |
| 150 | SharedFunctionInfo* shared); |
| 151 | |
| 152 | static void Setup(); |
| 153 | static void TearDown(); |
| 154 | |
| 155 | // Code generation support. |
| 156 | static int input_offset() { return OFFSET_OF(Deoptimizer, input_); } |
| 157 | static int output_count_offset() { |
| 158 | return OFFSET_OF(Deoptimizer, output_count_); |
| 159 | } |
| 160 | static int output_offset() { return OFFSET_OF(Deoptimizer, output_); } |
| 161 | |
| 162 | static int GetDeoptimizedCodeCount(); |
| 163 | |
| 164 | static const int kNotDeoptimizationEntry = -1; |
| 165 | |
| 166 | // Generators for the deoptimization entry code. |
| 167 | class EntryGenerator BASE_EMBEDDED { |
| 168 | public: |
| 169 | EntryGenerator(MacroAssembler* masm, BailoutType type) |
| 170 | : masm_(masm), type_(type) { } |
| 171 | virtual ~EntryGenerator() { } |
| 172 | |
| 173 | void Generate(); |
| 174 | |
| 175 | protected: |
| 176 | MacroAssembler* masm() const { return masm_; } |
| 177 | BailoutType type() const { return type_; } |
| 178 | |
| 179 | virtual void GeneratePrologue() { } |
| 180 | |
| 181 | private: |
| 182 | MacroAssembler* masm_; |
| 183 | Deoptimizer::BailoutType type_; |
| 184 | }; |
| 185 | |
| 186 | class TableEntryGenerator : public EntryGenerator { |
| 187 | public: |
| 188 | TableEntryGenerator(MacroAssembler* masm, BailoutType type, int count) |
| 189 | : EntryGenerator(masm, type), count_(count) { } |
| 190 | |
| 191 | protected: |
| 192 | virtual void GeneratePrologue(); |
| 193 | |
| 194 | private: |
| 195 | int count() const { return count_; } |
| 196 | |
| 197 | int count_; |
| 198 | }; |
| 199 | |
| 200 | private: |
| 201 | static const int kNumberOfEntries = 4096; |
| 202 | |
| 203 | Deoptimizer(JSFunction* function, |
| 204 | BailoutType type, |
| 205 | unsigned bailout_id, |
| 206 | Address from, |
| 207 | int fp_to_sp_delta); |
| 208 | void DeleteFrameDescriptions(); |
| 209 | |
| 210 | void DoComputeOutputFrames(); |
| 211 | void DoComputeOsrOutputFrame(); |
| 212 | void DoComputeFrame(TranslationIterator* iterator, int frame_index); |
| 213 | void DoTranslateCommand(TranslationIterator* iterator, |
| 214 | int frame_index, |
| 215 | unsigned output_offset); |
| 216 | // Translate a command for OSR. Updates the input offset to be used for |
| 217 | // the next command. Returns false if translation of the command failed |
| 218 | // (e.g., a number conversion failed) and may or may not have updated the |
| 219 | // input offset. |
| 220 | bool DoOsrTranslateCommand(TranslationIterator* iterator, |
| 221 | int* input_offset); |
| 222 | |
| 223 | unsigned ComputeInputFrameSize() const; |
| 224 | unsigned ComputeFixedSize(JSFunction* function) const; |
| 225 | |
| 226 | unsigned ComputeIncomingArgumentSize(JSFunction* function) const; |
| 227 | unsigned ComputeOutgoingArgumentSize() const; |
| 228 | |
| 229 | Object* ComputeLiteral(int index) const; |
| 230 | |
| 231 | void InsertHeapNumberValue(JavaScriptFrame* frame, |
| 232 | int stack_index, |
| 233 | double val, |
| 234 | int extra_slot_count); |
| 235 | |
| 236 | void AddInteger32Value(int frame_index, int slot_index, int32_t value); |
| 237 | void AddDoubleValue(int frame_index, int slot_index, double value); |
| 238 | |
| 239 | static LargeObjectChunk* CreateCode(BailoutType type); |
| 240 | static void GenerateDeoptimizationEntries( |
| 241 | MacroAssembler* masm, int count, BailoutType type); |
| 242 | |
| 243 | // Weak handle callback for deoptimizing code objects. |
| 244 | static void HandleWeakDeoptimizedCode( |
| 245 | v8::Persistent<v8::Value> obj, void* data); |
| 246 | static Code* FindDeoptimizingCodeFromAddress(Address addr); |
| 247 | static void RemoveDeoptimizingCode(Code* code); |
| 248 | |
| 249 | static LargeObjectChunk* eager_deoptimization_entry_code_; |
| 250 | static LargeObjectChunk* lazy_deoptimization_entry_code_; |
| 251 | static Deoptimizer* current_; |
| 252 | |
| 253 | // List of deoptimized code which still have references from active stack |
| 254 | // frames. These code objects are needed by the deoptimizer when deoptimizing |
| 255 | // a frame for which the code object for the function function has been |
| 256 | // changed from the code present when deoptimizing was done. |
| 257 | static DeoptimizingCodeListNode* deoptimizing_code_list_; |
| 258 | |
| 259 | JSFunction* function_; |
| 260 | Code* optimized_code_; |
| 261 | unsigned bailout_id_; |
| 262 | BailoutType bailout_type_; |
| 263 | Address from_; |
| 264 | int fp_to_sp_delta_; |
| 265 | |
| 266 | // Input frame description. |
| 267 | FrameDescription* input_; |
| 268 | // Number of output frames. |
| 269 | int output_count_; |
| 270 | // Array of output frame descriptions. |
| 271 | FrameDescription** output_; |
| 272 | |
| 273 | List<ValueDescriptionInteger32>* integer32_values_; |
| 274 | List<ValueDescriptionDouble>* double_values_; |
| 275 | |
| 276 | static int table_entry_size_; |
| 277 | |
| 278 | friend class FrameDescription; |
| 279 | friend class DeoptimizingCodeListNode; |
| 280 | }; |
| 281 | |
| 282 | |
| 283 | class FrameDescription { |
| 284 | public: |
| 285 | FrameDescription(uint32_t frame_size, |
| 286 | JSFunction* function); |
| 287 | |
| 288 | void* operator new(size_t size, uint32_t frame_size) { |
| 289 | return malloc(size + frame_size); |
| 290 | } |
| 291 | |
| 292 | void operator delete(void* description) { |
| 293 | free(description); |
| 294 | } |
| 295 | |
| 296 | intptr_t GetFrameSize() const { return frame_size_; } |
| 297 | |
| 298 | JSFunction* GetFunction() const { return function_; } |
| 299 | |
| 300 | unsigned GetOffsetFromSlotIndex(Deoptimizer* deoptimizer, int slot_index); |
| 301 | |
| 302 | intptr_t GetFrameSlot(unsigned offset) { |
| 303 | return *GetFrameSlotPointer(offset); |
| 304 | } |
| 305 | |
| 306 | double GetDoubleFrameSlot(unsigned offset) { |
| 307 | return *reinterpret_cast<double*>(GetFrameSlotPointer(offset)); |
| 308 | } |
| 309 | |
| 310 | void SetFrameSlot(unsigned offset, intptr_t value) { |
| 311 | *GetFrameSlotPointer(offset) = value; |
| 312 | } |
| 313 | |
| 314 | intptr_t GetRegister(unsigned n) const { |
| 315 | ASSERT(n < ARRAY_SIZE(registers_)); |
| 316 | return registers_[n]; |
| 317 | } |
| 318 | |
| 319 | double GetDoubleRegister(unsigned n) const { |
| 320 | ASSERT(n < ARRAY_SIZE(double_registers_)); |
| 321 | return double_registers_[n]; |
| 322 | } |
| 323 | |
| 324 | void SetRegister(unsigned n, intptr_t value) { |
| 325 | ASSERT(n < ARRAY_SIZE(registers_)); |
| 326 | registers_[n] = value; |
| 327 | } |
| 328 | |
| 329 | void SetDoubleRegister(unsigned n, double value) { |
| 330 | ASSERT(n < ARRAY_SIZE(double_registers_)); |
| 331 | double_registers_[n] = value; |
| 332 | } |
| 333 | |
| 334 | intptr_t GetTop() const { return top_; } |
| 335 | void SetTop(intptr_t top) { top_ = top; } |
| 336 | |
| 337 | intptr_t GetPc() const { return pc_; } |
| 338 | void SetPc(intptr_t pc) { pc_ = pc; } |
| 339 | |
| 340 | intptr_t GetFp() const { return fp_; } |
| 341 | void SetFp(intptr_t fp) { fp_ = fp; } |
| 342 | |
| 343 | Smi* GetState() const { return state_; } |
| 344 | void SetState(Smi* state) { state_ = state; } |
| 345 | |
| 346 | void SetContinuation(intptr_t pc) { continuation_ = pc; } |
| 347 | |
| 348 | static int registers_offset() { |
| 349 | return OFFSET_OF(FrameDescription, registers_); |
| 350 | } |
| 351 | |
| 352 | static int double_registers_offset() { |
| 353 | return OFFSET_OF(FrameDescription, double_registers_); |
| 354 | } |
| 355 | |
| 356 | static int frame_size_offset() { |
| 357 | return OFFSET_OF(FrameDescription, frame_size_); |
| 358 | } |
| 359 | |
| 360 | static int pc_offset() { |
| 361 | return OFFSET_OF(FrameDescription, pc_); |
| 362 | } |
| 363 | |
| 364 | static int state_offset() { |
| 365 | return OFFSET_OF(FrameDescription, state_); |
| 366 | } |
| 367 | |
| 368 | static int continuation_offset() { |
| 369 | return OFFSET_OF(FrameDescription, continuation_); |
| 370 | } |
| 371 | |
| 372 | static int frame_content_offset() { |
| 373 | return sizeof(FrameDescription); |
| 374 | } |
| 375 | |
| 376 | private: |
| 377 | static const uint32_t kZapUint32 = 0xbeeddead; |
| 378 | |
| 379 | uintptr_t frame_size_; // Number of bytes. |
| 380 | JSFunction* function_; |
| 381 | intptr_t registers_[Register::kNumRegisters]; |
| 382 | double double_registers_[DoubleRegister::kNumAllocatableRegisters]; |
| 383 | intptr_t top_; |
| 384 | intptr_t pc_; |
| 385 | intptr_t fp_; |
| 386 | Smi* state_; |
| 387 | |
| 388 | // Continuation is the PC where the execution continues after |
| 389 | // deoptimizing. |
| 390 | intptr_t continuation_; |
| 391 | |
| 392 | intptr_t* GetFrameSlotPointer(unsigned offset) { |
| 393 | ASSERT(offset < frame_size_); |
| 394 | return reinterpret_cast<intptr_t*>( |
| 395 | reinterpret_cast<Address>(this) + frame_content_offset() + offset); |
| 396 | } |
| 397 | }; |
| 398 | |
| 399 | |
| 400 | class TranslationBuffer BASE_EMBEDDED { |
| 401 | public: |
| 402 | TranslationBuffer() : contents_(256) { } |
| 403 | |
| 404 | int CurrentIndex() const { return contents_.length(); } |
| 405 | void Add(int32_t value); |
| 406 | |
| 407 | Handle<ByteArray> CreateByteArray(); |
| 408 | |
| 409 | private: |
| 410 | ZoneList<uint8_t> contents_; |
| 411 | }; |
| 412 | |
| 413 | |
| 414 | class TranslationIterator BASE_EMBEDDED { |
| 415 | public: |
| 416 | TranslationIterator(ByteArray* buffer, int index) |
| 417 | : buffer_(buffer), index_(index) { |
| 418 | ASSERT(index >= 0 && index < buffer->length()); |
| 419 | } |
| 420 | |
| 421 | int32_t Next(); |
| 422 | |
| 423 | bool HasNext() const { return index_ >= 0; } |
| 424 | |
| 425 | void Done() { index_ = -1; } |
| 426 | |
| 427 | void Skip(int n) { |
| 428 | for (int i = 0; i < n; i++) Next(); |
| 429 | } |
| 430 | |
| 431 | private: |
| 432 | ByteArray* buffer_; |
| 433 | int index_; |
| 434 | }; |
| 435 | |
| 436 | |
| 437 | class Translation BASE_EMBEDDED { |
| 438 | public: |
| 439 | enum Opcode { |
| 440 | BEGIN, |
| 441 | FRAME, |
| 442 | REGISTER, |
| 443 | INT32_REGISTER, |
| 444 | DOUBLE_REGISTER, |
| 445 | STACK_SLOT, |
| 446 | INT32_STACK_SLOT, |
| 447 | DOUBLE_STACK_SLOT, |
| 448 | LITERAL, |
| 449 | ARGUMENTS_OBJECT, |
| 450 | |
| 451 | // A prefix indicating that the next command is a duplicate of the one |
| 452 | // that follows it. |
| 453 | DUPLICATE |
| 454 | }; |
| 455 | |
| 456 | Translation(TranslationBuffer* buffer, int frame_count) |
| 457 | : buffer_(buffer), |
| 458 | index_(buffer->CurrentIndex()) { |
| 459 | buffer_->Add(BEGIN); |
| 460 | buffer_->Add(frame_count); |
| 461 | } |
| 462 | |
| 463 | int index() const { return index_; } |
| 464 | |
| 465 | // Commands. |
| 466 | void BeginFrame(int node_id, int literal_id, unsigned height); |
| 467 | void StoreRegister(Register reg); |
| 468 | void StoreInt32Register(Register reg); |
| 469 | void StoreDoubleRegister(DoubleRegister reg); |
| 470 | void StoreStackSlot(int index); |
| 471 | void StoreInt32StackSlot(int index); |
| 472 | void StoreDoubleStackSlot(int index); |
| 473 | void StoreLiteral(int literal_id); |
| 474 | void StoreArgumentsObject(); |
| 475 | void MarkDuplicate(); |
| 476 | |
| 477 | static int NumberOfOperandsFor(Opcode opcode); |
| 478 | |
| 479 | #ifdef OBJECT_PRINT |
| 480 | static const char* StringFor(Opcode opcode); |
| 481 | #endif |
| 482 | |
| 483 | private: |
| 484 | TranslationBuffer* buffer_; |
| 485 | int index_; |
| 486 | }; |
| 487 | |
| 488 | |
| 489 | // Linked list holding deoptimizing code objects. The deoptimizing code objects |
| 490 | // are kept as weak handles until they are no longer activated on the stack. |
| 491 | class DeoptimizingCodeListNode : public Malloced { |
| 492 | public: |
| 493 | explicit DeoptimizingCodeListNode(Code* code); |
| 494 | ~DeoptimizingCodeListNode(); |
| 495 | |
| 496 | DeoptimizingCodeListNode* next() const { return next_; } |
| 497 | void set_next(DeoptimizingCodeListNode* next) { next_ = next; } |
| 498 | Handle<Code> code() const { return code_; } |
| 499 | |
| 500 | private: |
| 501 | // Global (weak) handle to the deoptimizing code object. |
| 502 | Handle<Code> code_; |
| 503 | |
| 504 | // Next pointer for linked list. |
| 505 | DeoptimizingCodeListNode* next_; |
| 506 | }; |
| 507 | |
| 508 | |
| 509 | } } // namespace v8::internal |
| 510 | |
| 511 | #endif // V8_DEOPTIMIZER_H_ |