1 // Copyright 2012 the V8 project authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 #ifndef V8_DEBUG_H_ 6 #define V8_DEBUG_H_ 7 8 #include "src/allocation.h" 9 #include "src/arguments.h" 10 #include "src/assembler.h" 11 #include "src/execution.h" 12 #include "src/factory.h" 13 #include "src/flags.h" 14 #include "src/frames-inl.h" 15 #include "src/hashmap.h" 16 #include "src/liveedit.h" 17 #include "src/platform.h" 18 #include "src/string-stream.h" 19 #include "src/v8threads.h" 20 21 #include "include/v8-debug.h" 22 23 namespace v8 { 24 namespace internal { 25 26 27 // Forward declarations. 28 class DebugScope; 29 30 31 // Step actions. NOTE: These values are in macros.py as well. 32 enum StepAction { 33 StepNone = -1, // Stepping not prepared. 34 StepOut = 0, // Step out of the current function. 35 StepNext = 1, // Step to the next statement in the current function. 36 StepIn = 2, // Step into new functions invoked or the next statement 37 // in the current function. 38 StepMin = 3, // Perform a minimum step in the current function. 39 StepInMin = 4 // Step into new functions invoked or perform a minimum step 40 // in the current function. 41 }; 42 43 44 // Type of exception break. NOTE: These values are in macros.py as well. 45 enum ExceptionBreakType { 46 BreakException = 0, 47 BreakUncaughtException = 1 48 }; 49 50 51 // Type of exception break. NOTE: These values are in macros.py as well. 52 enum BreakLocatorType { 53 ALL_BREAK_LOCATIONS = 0, 54 SOURCE_BREAK_LOCATIONS = 1 55 }; 56 57 58 // The different types of breakpoint position alignments. 59 // Must match Debug.BreakPositionAlignment in debug-debugger.js 60 enum BreakPositionAlignment { 61 STATEMENT_ALIGNED = 0, 62 BREAK_POSITION_ALIGNED = 1 63 }; 64 65 66 // Class for iterating through the break points in a function and changing 67 // them. 68 class BreakLocationIterator { 69 public: 70 explicit BreakLocationIterator(Handle<DebugInfo> debug_info, 71 BreakLocatorType type); 72 virtual ~BreakLocationIterator(); 73 74 void Next(); 75 void Next(int count); 76 void FindBreakLocationFromAddress(Address pc); 77 void FindBreakLocationFromPosition(int position, 78 BreakPositionAlignment alignment); 79 void Reset(); 80 bool Done() const; 81 void SetBreakPoint(Handle<Object> break_point_object); 82 void ClearBreakPoint(Handle<Object> break_point_object); 83 void SetOneShot(); 84 void ClearOneShot(); 85 bool IsStepInLocation(Isolate* isolate); 86 void PrepareStepIn(Isolate* isolate); 87 bool IsExit() const; 88 bool HasBreakPoint(); 89 bool IsDebugBreak(); 90 Object* BreakPointObjects(); 91 void ClearAllDebugBreak(); 92 93 code_position()94 inline int code_position() { 95 return static_cast<int>(pc() - debug_info_->code()->entry()); 96 } break_point()97 inline int break_point() { return break_point_; } position()98 inline int position() { return position_; } statement_position()99 inline int statement_position() { return statement_position_; } pc()100 inline Address pc() { return reloc_iterator_->rinfo()->pc(); } code()101 inline Code* code() { return debug_info_->code(); } rinfo()102 inline RelocInfo* rinfo() { return reloc_iterator_->rinfo(); } rmode()103 inline RelocInfo::Mode rmode() const { 104 return reloc_iterator_->rinfo()->rmode(); 105 } original_rinfo()106 inline RelocInfo* original_rinfo() { 107 return reloc_iterator_original_->rinfo(); 108 } original_rmode()109 inline RelocInfo::Mode original_rmode() const { 110 return reloc_iterator_original_->rinfo()->rmode(); 111 } 112 113 bool IsDebuggerStatement(); 114 115 protected: 116 bool RinfoDone() const; 117 void RinfoNext(); 118 119 BreakLocatorType type_; 120 int break_point_; 121 int position_; 122 int statement_position_; 123 Handle<DebugInfo> debug_info_; 124 RelocIterator* reloc_iterator_; 125 RelocIterator* reloc_iterator_original_; 126 127 private: 128 void SetDebugBreak(); 129 void ClearDebugBreak(); 130 131 void SetDebugBreakAtIC(); 132 void ClearDebugBreakAtIC(); 133 134 bool IsDebugBreakAtReturn(); 135 void SetDebugBreakAtReturn(); 136 void ClearDebugBreakAtReturn(); 137 138 bool IsDebugBreakSlot(); 139 bool IsDebugBreakAtSlot(); 140 void SetDebugBreakAtSlot(); 141 void ClearDebugBreakAtSlot(); 142 143 DISALLOW_COPY_AND_ASSIGN(BreakLocationIterator); 144 }; 145 146 147 // Cache of all script objects in the heap. When a script is added a weak handle 148 // to it is created and that weak handle is stored in the cache. The weak handle 149 // callback takes care of removing the script from the cache. The key used in 150 // the cache is the script id. 151 class ScriptCache : private HashMap { 152 public: 153 explicit ScriptCache(Isolate* isolate); ~ScriptCache()154 virtual ~ScriptCache() { Clear(); } 155 156 // Add script to the cache. 157 void Add(Handle<Script> script); 158 159 // Return the scripts in the cache. 160 Handle<FixedArray> GetScripts(); 161 162 // Generate debugger events for collected scripts. 163 void ProcessCollectedScripts(); 164 165 private: 166 // Calculate the hash value from the key (script id). Hash(int key)167 static uint32_t Hash(int key) { 168 return ComputeIntegerHash(key, v8::internal::kZeroHashSeed); 169 } 170 171 // Clear the cache releasing all the weak handles. 172 void Clear(); 173 174 // Weak handle callback for scripts in the cache. 175 static void HandleWeakScript( 176 const v8::WeakCallbackData<v8::Value, void>& data); 177 178 Isolate* isolate_; 179 // List used during GC to temporarily store id's of collected scripts. 180 List<int> collected_scripts_; 181 }; 182 183 184 // Linked list holding debug info objects. The debug info objects are kept as 185 // weak handles to avoid a debug info object to keep a function alive. 186 class DebugInfoListNode { 187 public: 188 explicit DebugInfoListNode(DebugInfo* debug_info); 189 virtual ~DebugInfoListNode(); 190 next()191 DebugInfoListNode* next() { return next_; } set_next(DebugInfoListNode * next)192 void set_next(DebugInfoListNode* next) { next_ = next; } debug_info()193 Handle<DebugInfo> debug_info() { return debug_info_; } 194 195 private: 196 // Global (weak) handle to the debug info object. 197 Handle<DebugInfo> debug_info_; 198 199 // Next pointer for linked list. 200 DebugInfoListNode* next_; 201 }; 202 203 204 205 // Message delivered to the message handler callback. This is either a debugger 206 // event or the response to a command. 207 class MessageImpl: public v8::Debug::Message { 208 public: 209 // Create a message object for a debug event. 210 static MessageImpl NewEvent(DebugEvent event, 211 bool running, 212 Handle<JSObject> exec_state, 213 Handle<JSObject> event_data); 214 215 // Create a message object for the response to a debug command. 216 static MessageImpl NewResponse(DebugEvent event, 217 bool running, 218 Handle<JSObject> exec_state, 219 Handle<JSObject> event_data, 220 Handle<String> response_json, 221 v8::Debug::ClientData* client_data); 222 223 // Implementation of interface v8::Debug::Message. 224 virtual bool IsEvent() const; 225 virtual bool IsResponse() const; 226 virtual DebugEvent GetEvent() const; 227 virtual bool WillStartRunning() const; 228 virtual v8::Handle<v8::Object> GetExecutionState() const; 229 virtual v8::Handle<v8::Object> GetEventData() const; 230 virtual v8::Handle<v8::String> GetJSON() const; 231 virtual v8::Handle<v8::Context> GetEventContext() const; 232 virtual v8::Debug::ClientData* GetClientData() const; 233 virtual v8::Isolate* GetIsolate() const; 234 235 private: 236 MessageImpl(bool is_event, 237 DebugEvent event, 238 bool running, 239 Handle<JSObject> exec_state, 240 Handle<JSObject> event_data, 241 Handle<String> response_json, 242 v8::Debug::ClientData* client_data); 243 244 bool is_event_; // Does this message represent a debug event? 245 DebugEvent event_; // Debug event causing the break. 246 bool running_; // Will the VM start running after this event? 247 Handle<JSObject> exec_state_; // Current execution state. 248 Handle<JSObject> event_data_; // Data associated with the event. 249 Handle<String> response_json_; // Response JSON if message holds a response. 250 v8::Debug::ClientData* client_data_; // Client data passed with the request. 251 }; 252 253 254 // Details of the debug event delivered to the debug event listener. 255 class EventDetailsImpl : public v8::Debug::EventDetails { 256 public: 257 EventDetailsImpl(DebugEvent event, 258 Handle<JSObject> exec_state, 259 Handle<JSObject> event_data, 260 Handle<Object> callback_data, 261 v8::Debug::ClientData* client_data); 262 virtual DebugEvent GetEvent() const; 263 virtual v8::Handle<v8::Object> GetExecutionState() const; 264 virtual v8::Handle<v8::Object> GetEventData() const; 265 virtual v8::Handle<v8::Context> GetEventContext() const; 266 virtual v8::Handle<v8::Value> GetCallbackData() const; 267 virtual v8::Debug::ClientData* GetClientData() const; 268 private: 269 DebugEvent event_; // Debug event causing the break. 270 Handle<JSObject> exec_state_; // Current execution state. 271 Handle<JSObject> event_data_; // Data associated with the event. 272 Handle<Object> callback_data_; // User data passed with the callback 273 // when it was registered. 274 v8::Debug::ClientData* client_data_; // Data passed to DebugBreakForCommand. 275 }; 276 277 278 // Message send by user to v8 debugger or debugger output message. 279 // In addition to command text it may contain a pointer to some user data 280 // which are expected to be passed along with the command reponse to message 281 // handler. 282 class CommandMessage { 283 public: 284 static CommandMessage New(const Vector<uint16_t>& command, 285 v8::Debug::ClientData* data); 286 CommandMessage(); 287 288 // Deletes user data and disposes of the text. 289 void Dispose(); text()290 Vector<uint16_t> text() const { return text_; } client_data()291 v8::Debug::ClientData* client_data() const { return client_data_; } 292 private: 293 CommandMessage(const Vector<uint16_t>& text, 294 v8::Debug::ClientData* data); 295 296 Vector<uint16_t> text_; 297 v8::Debug::ClientData* client_data_; 298 }; 299 300 301 // A Queue of CommandMessage objects. A thread-safe version is 302 // LockingCommandMessageQueue, based on this class. 303 class CommandMessageQueue BASE_EMBEDDED { 304 public: 305 explicit CommandMessageQueue(int size); 306 ~CommandMessageQueue(); IsEmpty()307 bool IsEmpty() const { return start_ == end_; } 308 CommandMessage Get(); 309 void Put(const CommandMessage& message); Clear()310 void Clear() { start_ = end_ = 0; } // Queue is empty after Clear(). 311 private: 312 // Doubles the size of the message queue, and copies the messages. 313 void Expand(); 314 315 CommandMessage* messages_; 316 int start_; 317 int end_; 318 int size_; // The size of the queue buffer. Queue can hold size-1 messages. 319 }; 320 321 322 // LockingCommandMessageQueue is a thread-safe circular buffer of CommandMessage 323 // messages. The message data is not managed by LockingCommandMessageQueue. 324 // Pointers to the data are passed in and out. Implemented by adding a 325 // Mutex to CommandMessageQueue. Includes logging of all puts and gets. 326 class LockingCommandMessageQueue BASE_EMBEDDED { 327 public: 328 LockingCommandMessageQueue(Logger* logger, int size); 329 bool IsEmpty() const; 330 CommandMessage Get(); 331 void Put(const CommandMessage& message); 332 void Clear(); 333 private: 334 Logger* logger_; 335 CommandMessageQueue queue_; 336 mutable Mutex mutex_; 337 DISALLOW_COPY_AND_ASSIGN(LockingCommandMessageQueue); 338 }; 339 340 341 class PromiseOnStack { 342 public: 343 PromiseOnStack(Isolate* isolate, 344 PromiseOnStack* prev, 345 Handle<JSFunction> getter); 346 ~PromiseOnStack(); handler()347 StackHandler* handler() { return handler_; } getter()348 Handle<JSFunction> getter() { return getter_; } prev()349 PromiseOnStack* prev() { return prev_; } 350 private: 351 Isolate* isolate_; 352 StackHandler* handler_; 353 Handle<JSFunction> getter_; 354 PromiseOnStack* prev_; 355 }; 356 357 358 // This class contains the debugger support. The main purpose is to handle 359 // setting break points in the code. 360 // 361 // This class controls the debug info for all functions which currently have 362 // active breakpoints in them. This debug info is held in the heap root object 363 // debug_info which is a FixedArray. Each entry in this list is of class 364 // DebugInfo. 365 class Debug { 366 public: 367 enum AfterCompileFlags { 368 NO_AFTER_COMPILE_FLAGS, 369 SEND_WHEN_DEBUGGING 370 }; 371 372 // Debug event triggers. 373 void OnDebugBreak(Handle<Object> break_points_hit, bool auto_continue); 374 void OnException(Handle<Object> exception, bool uncaught); 375 void OnBeforeCompile(Handle<Script> script); 376 void OnAfterCompile(Handle<Script> script, 377 AfterCompileFlags after_compile_flags); 378 void OnScriptCollected(int id); 379 380 // API facing. 381 void SetEventListener(Handle<Object> callback, Handle<Object> data); 382 void SetMessageHandler(v8::Debug::MessageHandler handler); 383 void EnqueueCommandMessage(Vector<const uint16_t> command, 384 v8::Debug::ClientData* client_data = NULL); 385 // Enqueue a debugger command to the command queue for event listeners. 386 void EnqueueDebugCommand(v8::Debug::ClientData* client_data = NULL); 387 MUST_USE_RESULT MaybeHandle<Object> Call(Handle<JSFunction> fun, 388 Handle<Object> data); 389 Handle<Context> GetDebugContext(); 390 void HandleDebugBreak(); 391 void ProcessDebugMessages(bool debug_command_only); 392 393 // Internal logic 394 bool Load(); 395 void Break(Arguments args, JavaScriptFrame*); 396 void SetAfterBreakTarget(JavaScriptFrame* frame); 397 398 // Scripts handling. 399 Handle<FixedArray> GetLoadedScripts(); 400 401 // Break point handling. 402 bool SetBreakPoint(Handle<JSFunction> function, 403 Handle<Object> break_point_object, 404 int* source_position); 405 bool SetBreakPointForScript(Handle<Script> script, 406 Handle<Object> break_point_object, 407 int* source_position, 408 BreakPositionAlignment alignment); 409 void ClearBreakPoint(Handle<Object> break_point_object); 410 void ClearAllBreakPoints(); 411 void FloodWithOneShot(Handle<JSFunction> function); 412 void FloodBoundFunctionWithOneShot(Handle<JSFunction> function); 413 void FloodHandlerWithOneShot(); 414 void ChangeBreakOnException(ExceptionBreakType type, bool enable); 415 bool IsBreakOnException(ExceptionBreakType type); 416 417 // Stepping handling. 418 void PrepareStep(StepAction step_action, 419 int step_count, 420 StackFrame::Id frame_id); 421 void ClearStepping(); 422 void ClearStepOut(); IsStepping()423 bool IsStepping() { return thread_local_.step_count_ > 0; } 424 bool StepNextContinue(BreakLocationIterator* break_location_iterator, 425 JavaScriptFrame* frame); StepInActive()426 bool StepInActive() { return thread_local_.step_into_fp_ != 0; } 427 void HandleStepIn(Handle<JSFunction> function, 428 Handle<Object> holder, 429 Address fp, 430 bool is_constructor); StepOutActive()431 bool StepOutActive() { return thread_local_.step_out_fp_ != 0; } 432 433 // Purge all code objects that have no debug break slots. 434 void PrepareForBreakPoints(); 435 436 // Returns whether the operation succeeded. Compilation can only be triggered 437 // if a valid closure is passed as the second argument, otherwise the shared 438 // function needs to be compiled already. 439 bool EnsureDebugInfo(Handle<SharedFunctionInfo> shared, 440 Handle<JSFunction> function); 441 static Handle<DebugInfo> GetDebugInfo(Handle<SharedFunctionInfo> shared); 442 static bool HasDebugInfo(Handle<SharedFunctionInfo> shared); 443 444 // This function is used in FunctionNameUsing* tests. 445 Object* FindSharedFunctionInfoInScript(Handle<Script> script, int position); 446 447 // Returns true if the current stub call is patched to call the debugger. 448 static bool IsDebugBreak(Address addr); 449 // Returns true if the current return statement has been patched to be 450 // a debugger breakpoint. 451 static bool IsDebugBreakAtReturn(RelocInfo* rinfo); 452 453 static Handle<Object> GetSourceBreakLocations( 454 Handle<SharedFunctionInfo> shared, 455 BreakPositionAlignment position_aligment); 456 457 // Check whether a global object is the debug global object. 458 bool IsDebugGlobal(GlobalObject* global); 459 460 // Check whether this frame is just about to return. 461 bool IsBreakAtReturn(JavaScriptFrame* frame); 462 463 // Promise handling. 464 void PromiseHandlePrologue(Handle<JSFunction> promise_getter); 465 void PromiseHandleEpilogue(); 466 467 // Support for LiveEdit 468 void FramesHaveBeenDropped(StackFrame::Id new_break_frame_id, 469 LiveEdit::FrameDropMode mode, 470 Object** restarter_frame_function_pointer); 471 472 // Passed to MakeWeak. 473 static void HandleWeakDebugInfo( 474 const v8::WeakCallbackData<v8::Value, void>& data); 475 476 // Threading support. 477 char* ArchiveDebug(char* to); 478 char* RestoreDebug(char* from); 479 static int ArchiveSpacePerThread(); FreeThreadResources()480 void FreeThreadResources() { } 481 482 // Record function from which eval was called. 483 static void RecordEvalCaller(Handle<Script> script); 484 485 // Garbage collection notifications. 486 void AfterGarbageCollection(); 487 488 // Flags and states. debugger_entry()489 DebugScope* debugger_entry() { return thread_local_.current_debug_scope_; } debug_context()490 inline Handle<Context> debug_context() { return debug_context_; } set_live_edit_enabled(bool v)491 void set_live_edit_enabled(bool v) { live_edit_enabled_ = v; } live_edit_enabled()492 bool live_edit_enabled() const { 493 return FLAG_enable_liveedit && live_edit_enabled_ ; 494 } 495 is_active()496 inline bool is_active() const { return is_active_; } is_loaded()497 inline bool is_loaded() const { return !debug_context_.is_null(); } has_break_points()498 inline bool has_break_points() const { return has_break_points_; } in_debug_scope()499 inline bool in_debug_scope() const { 500 return thread_local_.current_debug_scope_ != NULL; 501 } set_disable_break(bool v)502 void set_disable_break(bool v) { break_disabled_ = v; } 503 break_frame_id()504 StackFrame::Id break_frame_id() { return thread_local_.break_frame_id_; } break_id()505 int break_id() { return thread_local_.break_id_; } 506 507 // Support for embedding into generated code. after_break_target_address()508 Address after_break_target_address() { 509 return reinterpret_cast<Address>(&after_break_target_); 510 } 511 restarter_frame_function_pointer_address()512 Address restarter_frame_function_pointer_address() { 513 Object*** address = &thread_local_.restarter_frame_function_pointer_; 514 return reinterpret_cast<Address>(address); 515 } 516 step_in_fp_addr()517 Address step_in_fp_addr() { 518 return reinterpret_cast<Address>(&thread_local_.step_into_fp_); 519 } 520 521 private: 522 explicit Debug(Isolate* isolate); 523 524 void UpdateState(); 525 void Unload(); SetNextBreakId()526 void SetNextBreakId() { 527 thread_local_.break_id_ = ++thread_local_.break_count_; 528 } 529 530 // Check whether there are commands in the command queue. has_commands()531 inline bool has_commands() const { return !command_queue_.IsEmpty(); } ignore_events()532 inline bool ignore_events() const { return is_suppressed_ || !is_active_; } 533 534 // Constructors for debug event objects. 535 MUST_USE_RESULT MaybeHandle<Object> MakeJSObject( 536 const char* constructor_name, 537 int argc, 538 Handle<Object> argv[]); 539 MUST_USE_RESULT MaybeHandle<Object> MakeExecutionState(); 540 MUST_USE_RESULT MaybeHandle<Object> MakeBreakEvent( 541 Handle<Object> break_points_hit); 542 MUST_USE_RESULT MaybeHandle<Object> MakeExceptionEvent( 543 Handle<Object> exception, 544 bool uncaught, 545 Handle<Object> promise); 546 MUST_USE_RESULT MaybeHandle<Object> MakeCompileEvent( 547 Handle<Script> script, bool before); 548 MUST_USE_RESULT MaybeHandle<Object> MakeScriptCollectedEvent(int id); 549 550 // Mirror cache handling. 551 void ClearMirrorCache(); 552 553 // Returns a promise if it does not have a reject handler. 554 Handle<Object> GetPromiseForUncaughtException(); 555 556 void CallEventCallback(v8::DebugEvent event, 557 Handle<Object> exec_state, 558 Handle<Object> event_data, 559 v8::Debug::ClientData* client_data); 560 void ProcessDebugEvent(v8::DebugEvent event, 561 Handle<JSObject> event_data, 562 bool auto_continue); 563 void NotifyMessageHandler(v8::DebugEvent event, 564 Handle<JSObject> exec_state, 565 Handle<JSObject> event_data, 566 bool auto_continue); 567 void InvokeMessageHandler(MessageImpl message); 568 569 static bool CompileDebuggerScript(Isolate* isolate, int index); 570 void ClearOneShot(); 571 void ActivateStepIn(StackFrame* frame); 572 void ClearStepIn(); 573 void ActivateStepOut(StackFrame* frame); 574 void ClearStepNext(); 575 // Returns whether the compile succeeded. 576 void RemoveDebugInfo(Handle<DebugInfo> debug_info); 577 Handle<Object> CheckBreakPoints(Handle<Object> break_point); 578 bool CheckBreakPoint(Handle<Object> break_point_object); 579 AssertDebugContext()580 inline void AssertDebugContext() { 581 ASSERT(isolate_->context() == *debug_context()); 582 ASSERT(in_debug_scope()); 583 } 584 585 void ThreadInit(); 586 587 // Global handles. 588 Handle<Context> debug_context_; 589 Handle<Object> event_listener_; 590 Handle<Object> event_listener_data_; 591 592 v8::Debug::MessageHandler message_handler_; 593 594 static const int kQueueInitialSize = 4; 595 Semaphore command_received_; // Signaled for each command received. 596 LockingCommandMessageQueue command_queue_; 597 LockingCommandMessageQueue event_command_queue_; 598 599 bool is_active_; 600 bool is_suppressed_; 601 bool live_edit_enabled_; 602 bool has_break_points_; 603 bool break_disabled_; 604 bool break_on_exception_; 605 bool break_on_uncaught_exception_; 606 607 ScriptCache* script_cache_; // Cache of all scripts in the heap. 608 DebugInfoListNode* debug_info_list_; // List of active debug info objects. 609 610 // Storage location for jump when exiting debug break calls. 611 // Note that this address is not GC safe. It should be computed immediately 612 // before returning to the DebugBreakCallHelper. 613 Address after_break_target_; 614 615 // Per-thread data. 616 class ThreadLocal { 617 public: 618 // Top debugger entry. 619 DebugScope* current_debug_scope_; 620 621 // Counter for generating next break id. 622 int break_count_; 623 624 // Current break id. 625 int break_id_; 626 627 // Frame id for the frame of the current break. 628 StackFrame::Id break_frame_id_; 629 630 // Step action for last step performed. 631 StepAction last_step_action_; 632 633 // Source statement position from last step next action. 634 int last_statement_position_; 635 636 // Number of steps left to perform before debug event. 637 int step_count_; 638 639 // Frame pointer from last step next action. 640 Address last_fp_; 641 642 // Number of queued steps left to perform before debug event. 643 int queued_step_count_; 644 645 // Frame pointer for frame from which step in was performed. 646 Address step_into_fp_; 647 648 // Frame pointer for the frame where debugger should be called when current 649 // step out action is completed. 650 Address step_out_fp_; 651 652 // Stores the way how LiveEdit has patched the stack. It is used when 653 // debugger returns control back to user script. 654 LiveEdit::FrameDropMode frame_drop_mode_; 655 656 // When restarter frame is on stack, stores the address 657 // of the pointer to function being restarted. Otherwise (most of the time) 658 // stores NULL. This pointer is used with 'step in' implementation. 659 Object** restarter_frame_function_pointer_; 660 661 // When a promise is being resolved, we may want to trigger a debug event 662 // if we catch a throw. For this purpose we remember the try-catch 663 // handler address that would catch the exception. We also hold onto a 664 // closure that returns a promise if the exception is considered uncaught. 665 // Due to the possibility of reentry we use a linked list. 666 PromiseOnStack* promise_on_stack_; 667 }; 668 669 // Storage location for registers when handling debug break calls 670 ThreadLocal thread_local_; 671 672 Isolate* isolate_; 673 674 friend class Isolate; 675 friend class DebugScope; 676 friend class DisableBreak; 677 friend class LiveEdit; 678 friend class SuppressDebug; 679 680 friend Handle<FixedArray> GetDebuggedFunctions(); // In test-debug.cc 681 friend void CheckDebuggerUnloaded(bool check_functions); // In test-debug.cc 682 683 DISALLOW_COPY_AND_ASSIGN(Debug); 684 }; 685 686 687 DECLARE_RUNTIME_FUNCTION(Debug_Break); 688 689 690 // This scope is used to load and enter the debug context and create a new 691 // break state. Leaving the scope will restore the previous state. 692 // On failure to load, FailedToEnter returns true. 693 class DebugScope BASE_EMBEDDED { 694 public: 695 explicit DebugScope(Debug* debug); 696 ~DebugScope(); 697 698 // Check whether loading was successful. failed()699 inline bool failed() { return failed_; } 700 701 // Get the active context from before entering the debugger. GetContext()702 inline Handle<Context> GetContext() { return save_.context(); } 703 704 private: isolate()705 Isolate* isolate() { return debug_->isolate_; } 706 707 Debug* debug_; 708 DebugScope* prev_; // Previous scope if entered recursively. 709 StackFrame::Id break_frame_id_; // Previous break frame id. 710 int break_id_; // Previous break id. 711 bool failed_; // Did the debug context fail to load? 712 SaveContext save_; // Saves previous context. 713 }; 714 715 716 // Stack allocated class for disabling break. 717 class DisableBreak BASE_EMBEDDED { 718 public: DisableBreak(Debug * debug,bool disable_break)719 explicit DisableBreak(Debug* debug, bool disable_break) 720 : debug_(debug), old_state_(debug->break_disabled_) { 721 debug_->break_disabled_ = disable_break; 722 } ~DisableBreak()723 ~DisableBreak() { debug_->break_disabled_ = old_state_; } 724 725 private: 726 Debug* debug_; 727 bool old_state_; 728 DISALLOW_COPY_AND_ASSIGN(DisableBreak); 729 }; 730 731 732 class SuppressDebug BASE_EMBEDDED { 733 public: SuppressDebug(Debug * debug)734 explicit SuppressDebug(Debug* debug) 735 : debug_(debug), old_state_(debug->is_suppressed_) { 736 debug_->is_suppressed_ = true; 737 } ~SuppressDebug()738 ~SuppressDebug() { debug_->is_suppressed_ = old_state_; } 739 740 private: 741 Debug* debug_; 742 bool old_state_; 743 DISALLOW_COPY_AND_ASSIGN(SuppressDebug); 744 }; 745 746 747 // Code generator routines. 748 class DebugCodegen : public AllStatic { 749 public: 750 static void GenerateSlot(MacroAssembler* masm); 751 static void GenerateCallICStubDebugBreak(MacroAssembler* masm); 752 static void GenerateLoadICDebugBreak(MacroAssembler* masm); 753 static void GenerateStoreICDebugBreak(MacroAssembler* masm); 754 static void GenerateKeyedLoadICDebugBreak(MacroAssembler* masm); 755 static void GenerateKeyedStoreICDebugBreak(MacroAssembler* masm); 756 static void GenerateCompareNilICDebugBreak(MacroAssembler* masm); 757 static void GenerateReturnDebugBreak(MacroAssembler* masm); 758 static void GenerateCallFunctionStubDebugBreak(MacroAssembler* masm); 759 static void GenerateCallConstructStubDebugBreak(MacroAssembler* masm); 760 static void GenerateCallConstructStubRecordDebugBreak(MacroAssembler* masm); 761 static void GenerateSlotDebugBreak(MacroAssembler* masm); 762 static void GeneratePlainReturnLiveEdit(MacroAssembler* masm); 763 764 // FrameDropper is a code replacement for a JavaScript frame with possibly 765 // several frames above. 766 // There is no calling conventions here, because it never actually gets 767 // called, it only gets returned to. 768 static void GenerateFrameDropperLiveEdit(MacroAssembler* masm); 769 }; 770 771 772 } } // namespace v8::internal 773 774 #endif // V8_DEBUG_H_ 775