Fix bug in compilation-handlescope.
[platform/upstream/v8.git] / src / api.h
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27
28 #ifndef V8_API_H_
29 #define V8_API_H_
30
31 #include "v8.h"
32
33 #include "../include/v8-testing.h"
34 #include "apiutils.h"
35 #include "contexts.h"
36 #include "factory.h"
37 #include "isolate.h"
38 #include "list-inl.h"
39
40 namespace v8 {
41
42 // Constants used in the implementation of the API.  The most natural thing
43 // would usually be to place these with the classes that use them, but
44 // we want to keep them out of v8.h because it is an externally
45 // visible file.
46 class Consts {
47  public:
48   enum TemplateType {
49     FUNCTION_TEMPLATE = 0,
50     OBJECT_TEMPLATE = 1
51   };
52 };
53
54
55 // Utilities for working with neander-objects, primitive
56 // env-independent JSObjects used by the api.
57 class NeanderObject {
58  public:
59   explicit NeanderObject(int size);
60   explicit inline NeanderObject(v8::internal::Handle<v8::internal::Object> obj);
61   explicit inline NeanderObject(v8::internal::Object* obj);
62   inline v8::internal::Object* get(int index);
63   inline void set(int index, v8::internal::Object* value);
64   inline v8::internal::Handle<v8::internal::JSObject> value() { return value_; }
65   int size();
66  private:
67   v8::internal::Handle<v8::internal::JSObject> value_;
68 };
69
70
71 // Utilities for working with neander-arrays, a simple extensible
72 // array abstraction built on neander-objects.
73 class NeanderArray {
74  public:
75   NeanderArray();
76   explicit inline NeanderArray(v8::internal::Handle<v8::internal::Object> obj);
77   inline v8::internal::Handle<v8::internal::JSObject> value() {
78     return obj_.value();
79   }
80
81   void add(v8::internal::Handle<v8::internal::Object> value);
82
83   int length();
84
85   v8::internal::Object* get(int index);
86   // Change the value at an index to undefined value. If the index is
87   // out of bounds, the request is ignored. Returns the old value.
88   void set(int index, v8::internal::Object* value);
89  private:
90   NeanderObject obj_;
91 };
92
93
94 NeanderObject::NeanderObject(v8::internal::Handle<v8::internal::Object> obj)
95     : value_(v8::internal::Handle<v8::internal::JSObject>::cast(obj)) { }
96
97
98 NeanderObject::NeanderObject(v8::internal::Object* obj)
99     : value_(v8::internal::Handle<v8::internal::JSObject>(
100         v8::internal::JSObject::cast(obj))) { }
101
102
103 NeanderArray::NeanderArray(v8::internal::Handle<v8::internal::Object> obj)
104     : obj_(obj) { }
105
106
107 v8::internal::Object* NeanderObject::get(int offset) {
108   ASSERT(value()->HasFastObjectElements());
109   return v8::internal::FixedArray::cast(value()->elements())->get(offset);
110 }
111
112
113 void NeanderObject::set(int offset, v8::internal::Object* value) {
114   ASSERT(value_->HasFastObjectElements());
115   v8::internal::FixedArray::cast(value_->elements())->set(offset, value);
116 }
117
118
119 template <typename T> inline T ToCData(v8::internal::Object* obj) {
120   STATIC_ASSERT(sizeof(T) == sizeof(v8::internal::Address));
121   return reinterpret_cast<T>(
122       reinterpret_cast<intptr_t>(
123           v8::internal::Foreign::cast(obj)->foreign_address()));
124 }
125
126
127 template <typename T>
128 inline v8::internal::Handle<v8::internal::Object> FromCData(T obj) {
129   STATIC_ASSERT(sizeof(T) == sizeof(v8::internal::Address));
130   return FACTORY->NewForeign(
131       reinterpret_cast<v8::internal::Address>(reinterpret_cast<intptr_t>(obj)));
132 }
133
134
135 class ApiFunction {
136  public:
137   explicit ApiFunction(v8::internal::Address addr) : addr_(addr) { }
138   v8::internal::Address address() { return addr_; }
139  private:
140   v8::internal::Address addr_;
141 };
142
143
144
145 class RegisteredExtension {
146  public:
147   explicit RegisteredExtension(Extension* extension);
148   static void Register(RegisteredExtension* that);
149   static void UnregisterAll();
150   Extension* extension() { return extension_; }
151   RegisteredExtension* next() { return next_; }
152   RegisteredExtension* next_auto() { return next_auto_; }
153   static RegisteredExtension* first_extension() { return first_extension_; }
154  private:
155   Extension* extension_;
156   RegisteredExtension* next_;
157   RegisteredExtension* next_auto_;
158   static RegisteredExtension* first_extension_;
159 };
160
161
162 class Utils {
163  public:
164   static bool ReportApiFailure(const char* location, const char* message);
165
166   static Local<FunctionTemplate> ToFunctionTemplate(NeanderObject obj);
167   static Local<ObjectTemplate> ToObjectTemplate(NeanderObject obj);
168
169   static inline Local<Context> ToLocal(
170       v8::internal::Handle<v8::internal::Context> obj);
171   static inline Local<Value> ToLocal(
172       v8::internal::Handle<v8::internal::Object> obj);
173   static inline Local<Function> ToLocal(
174       v8::internal::Handle<v8::internal::JSFunction> obj);
175   static inline Local<String> ToLocal(
176       v8::internal::Handle<v8::internal::String> obj);
177   static inline Local<RegExp> ToLocal(
178       v8::internal::Handle<v8::internal::JSRegExp> obj);
179   static inline Local<Object> ToLocal(
180       v8::internal::Handle<v8::internal::JSObject> obj);
181   static inline Local<Array> ToLocal(
182       v8::internal::Handle<v8::internal::JSArray> obj);
183   static inline Local<External> ToLocal(
184       v8::internal::Handle<v8::internal::Foreign> obj);
185   static inline Local<Message> MessageToLocal(
186       v8::internal::Handle<v8::internal::Object> obj);
187   static inline Local<StackTrace> StackTraceToLocal(
188       v8::internal::Handle<v8::internal::JSArray> obj);
189   static inline Local<StackFrame> StackFrameToLocal(
190       v8::internal::Handle<v8::internal::JSObject> obj);
191   static inline Local<Number> NumberToLocal(
192       v8::internal::Handle<v8::internal::Object> obj);
193   static inline Local<Integer> IntegerToLocal(
194       v8::internal::Handle<v8::internal::Object> obj);
195   static inline Local<Uint32> Uint32ToLocal(
196       v8::internal::Handle<v8::internal::Object> obj);
197   static inline Local<FunctionTemplate> ToLocal(
198       v8::internal::Handle<v8::internal::FunctionTemplateInfo> obj);
199   static inline Local<ObjectTemplate> ToLocal(
200       v8::internal::Handle<v8::internal::ObjectTemplateInfo> obj);
201   static inline Local<Signature> ToLocal(
202       v8::internal::Handle<v8::internal::SignatureInfo> obj);
203   static inline Local<AccessorSignature> AccessorSignatureToLocal(
204       v8::internal::Handle<v8::internal::FunctionTemplateInfo> obj);
205   static inline Local<TypeSwitch> ToLocal(
206       v8::internal::Handle<v8::internal::TypeSwitchInfo> obj);
207
208   static inline v8::internal::Handle<v8::internal::TemplateInfo>
209       OpenHandle(const Template* that);
210   static inline v8::internal::Handle<v8::internal::FunctionTemplateInfo>
211       OpenHandle(const FunctionTemplate* that);
212   static inline v8::internal::Handle<v8::internal::ObjectTemplateInfo>
213       OpenHandle(const ObjectTemplate* that);
214   static inline v8::internal::Handle<v8::internal::Object>
215       OpenHandle(const Data* data);
216   static inline v8::internal::Handle<v8::internal::JSRegExp>
217       OpenHandle(const RegExp* data);
218   static inline v8::internal::Handle<v8::internal::JSObject>
219       OpenHandle(const v8::Object* data);
220   static inline v8::internal::Handle<v8::internal::JSArray>
221       OpenHandle(const v8::Array* data);
222   static inline v8::internal::Handle<v8::internal::String>
223       OpenHandle(const String* data);
224   static inline v8::internal::Handle<v8::internal::Object>
225       OpenHandle(const Script* data);
226   static inline v8::internal::Handle<v8::internal::JSFunction>
227       OpenHandle(const Function* data);
228   static inline v8::internal::Handle<v8::internal::JSObject>
229       OpenHandle(const Message* message);
230   static inline v8::internal::Handle<v8::internal::JSArray>
231       OpenHandle(const StackTrace* stack_trace);
232   static inline v8::internal::Handle<v8::internal::JSObject>
233       OpenHandle(const StackFrame* stack_frame);
234   static inline v8::internal::Handle<v8::internal::Context>
235       OpenHandle(const v8::Context* context);
236   static inline v8::internal::Handle<v8::internal::SignatureInfo>
237       OpenHandle(const v8::Signature* sig);
238   static inline v8::internal::Handle<v8::internal::FunctionTemplateInfo>
239       OpenHandle(const v8::AccessorSignature* sig);
240   static inline v8::internal::Handle<v8::internal::TypeSwitchInfo>
241       OpenHandle(const v8::TypeSwitch* that);
242   static inline v8::internal::Handle<v8::internal::Foreign>
243       OpenHandle(const v8::External* that);
244 };
245
246
247 template <class T>
248 inline T* ToApi(v8::internal::Handle<v8::internal::Object> obj) {
249   return reinterpret_cast<T*>(obj.location());
250 }
251
252
253 template <class T>
254 v8::internal::Handle<T> v8::internal::Handle<T>::EscapeFrom(
255     v8::HandleScope* scope) {
256   v8::internal::Handle<T> handle;
257   if (!is_null()) {
258     handle = *this;
259   }
260   return Utils::OpenHandle(*scope->Close(Utils::ToLocal(handle)));
261 }
262
263
264 // Implementations of ToLocal
265
266 #define MAKE_TO_LOCAL(Name, From, To)                                       \
267   Local<v8::To> Utils::Name(v8::internal::Handle<v8::internal::From> obj) { \
268     ASSERT(obj.is_null() || !obj->IsTheHole());                             \
269     return Local<To>(reinterpret_cast<To*>(obj.location()));                \
270   }
271
272 MAKE_TO_LOCAL(ToLocal, Context, Context)
273 MAKE_TO_LOCAL(ToLocal, Object, Value)
274 MAKE_TO_LOCAL(ToLocal, JSFunction, Function)
275 MAKE_TO_LOCAL(ToLocal, String, String)
276 MAKE_TO_LOCAL(ToLocal, JSRegExp, RegExp)
277 MAKE_TO_LOCAL(ToLocal, JSObject, Object)
278 MAKE_TO_LOCAL(ToLocal, JSArray, Array)
279 MAKE_TO_LOCAL(ToLocal, Foreign, External)
280 MAKE_TO_LOCAL(ToLocal, FunctionTemplateInfo, FunctionTemplate)
281 MAKE_TO_LOCAL(ToLocal, ObjectTemplateInfo, ObjectTemplate)
282 MAKE_TO_LOCAL(ToLocal, SignatureInfo, Signature)
283 MAKE_TO_LOCAL(AccessorSignatureToLocal, FunctionTemplateInfo, AccessorSignature)
284 MAKE_TO_LOCAL(ToLocal, TypeSwitchInfo, TypeSwitch)
285 MAKE_TO_LOCAL(MessageToLocal, Object, Message)
286 MAKE_TO_LOCAL(StackTraceToLocal, JSArray, StackTrace)
287 MAKE_TO_LOCAL(StackFrameToLocal, JSObject, StackFrame)
288 MAKE_TO_LOCAL(NumberToLocal, Object, Number)
289 MAKE_TO_LOCAL(IntegerToLocal, Object, Integer)
290 MAKE_TO_LOCAL(Uint32ToLocal, Object, Uint32)
291
292 #undef MAKE_TO_LOCAL
293
294
295 // Implementations of OpenHandle
296
297 #define MAKE_OPEN_HANDLE(From, To) \
298   v8::internal::Handle<v8::internal::To> Utils::OpenHandle(\
299     const v8::From* that) { \
300     return v8::internal::Handle<v8::internal::To>( \
301         reinterpret_cast<v8::internal::To**>(const_cast<v8::From*>(that))); \
302   }
303
304 MAKE_OPEN_HANDLE(Template, TemplateInfo)
305 MAKE_OPEN_HANDLE(FunctionTemplate, FunctionTemplateInfo)
306 MAKE_OPEN_HANDLE(ObjectTemplate, ObjectTemplateInfo)
307 MAKE_OPEN_HANDLE(Signature, SignatureInfo)
308 MAKE_OPEN_HANDLE(AccessorSignature, FunctionTemplateInfo)
309 MAKE_OPEN_HANDLE(TypeSwitch, TypeSwitchInfo)
310 MAKE_OPEN_HANDLE(Data, Object)
311 MAKE_OPEN_HANDLE(RegExp, JSRegExp)
312 MAKE_OPEN_HANDLE(Object, JSObject)
313 MAKE_OPEN_HANDLE(Array, JSArray)
314 MAKE_OPEN_HANDLE(String, String)
315 MAKE_OPEN_HANDLE(Script, Object)
316 MAKE_OPEN_HANDLE(Function, JSFunction)
317 MAKE_OPEN_HANDLE(Message, JSObject)
318 MAKE_OPEN_HANDLE(Context, Context)
319 MAKE_OPEN_HANDLE(External, Foreign)
320 MAKE_OPEN_HANDLE(StackTrace, JSArray)
321 MAKE_OPEN_HANDLE(StackFrame, JSObject)
322
323 #undef MAKE_OPEN_HANDLE
324
325
326 namespace internal {
327
328 // Tracks string usage to help make better decisions when
329 // externalizing strings.
330 //
331 // Implementation note: internally this class only tracks fresh
332 // strings and keeps a single use counter for them.
333 class StringTracker {
334  public:
335   // Records that the given string's characters were copied to some
336   // external buffer. If this happens often we should honor
337   // externalization requests for the string.
338   void RecordWrite(Handle<String> string) {
339     Address address = reinterpret_cast<Address>(*string);
340     Address top = isolate_->heap()->NewSpaceTop();
341     if (IsFreshString(address, top)) {
342       IncrementUseCount(top);
343     }
344   }
345
346   // Estimates freshness and use frequency of the given string based
347   // on how close it is to the new space top and the recorded usage
348   // history.
349   inline bool IsFreshUnusedString(Handle<String> string) {
350     Address address = reinterpret_cast<Address>(*string);
351     Address top = isolate_->heap()->NewSpaceTop();
352     return IsFreshString(address, top) && IsUseCountLow(top);
353   }
354
355  private:
356   StringTracker() : use_count_(0), last_top_(NULL), isolate_(NULL) { }
357
358   static inline bool IsFreshString(Address string, Address top) {
359     return top - kFreshnessLimit <= string && string <= top;
360   }
361
362   inline bool IsUseCountLow(Address top) {
363     if (last_top_ != top) return true;
364     return use_count_ < kUseLimit;
365   }
366
367   inline void IncrementUseCount(Address top) {
368     if (last_top_ != top) {
369       use_count_ = 0;
370       last_top_ = top;
371     }
372     ++use_count_;
373   }
374
375   // Single use counter shared by all fresh strings.
376   int use_count_;
377
378   // Last new space top when the use count above was valid.
379   Address last_top_;
380
381   Isolate* isolate_;
382
383   // How close to the new space top a fresh string has to be.
384   static const int kFreshnessLimit = 1024;
385
386   // The number of uses required to consider a string useful.
387   static const int kUseLimit = 32;
388
389   friend class Isolate;
390
391   DISALLOW_COPY_AND_ASSIGN(StringTracker);
392 };
393
394
395 class DeferredHandles {
396  public:
397   ~DeferredHandles();
398
399  private:
400   DeferredHandles(DeferredHandles* next, Object** first_block_limit,
401                   HandleScopeImplementer* impl)
402       : next_(next), previous_(NULL), first_block_limit_(first_block_limit),
403         impl_(impl) {}
404
405   void Iterate(ObjectVisitor* v);
406
407   List<Object**> blocks_;
408   DeferredHandles* next_;
409   DeferredHandles* previous_;
410   Object** first_block_limit_;
411   HandleScopeImplementer* impl_;
412
413   friend class HandleScopeImplementer;
414 };
415
416
417 // This class is here in order to be able to declare it a friend of
418 // HandleScope.  Moving these methods to be members of HandleScope would be
419 // neat in some ways, but it would expose internal implementation details in
420 // our public header file, which is undesirable.
421 //
422 // An isolate has a single instance of this class to hold the current thread's
423 // data. In multithreaded V8 programs this data is copied in and out of storage
424 // so that the currently executing thread always has its own copy of this
425 // data.
426 class HandleScopeImplementer {
427  public:
428   explicit HandleScopeImplementer(Isolate* isolate)
429       : isolate_(isolate),
430         blocks_(0),
431         entered_contexts_(0),
432         saved_contexts_(0),
433         spare_(NULL),
434         call_depth_(0),
435         last_handle_before_deferred_block_(NULL),
436         deferred_handles_head_(NULL) { }
437
438   ~HandleScopeImplementer() {
439     DeleteArray(spare_);
440   }
441
442   // Threading support for handle data.
443   static int ArchiveSpacePerThread();
444   char* RestoreThread(char* from);
445   char* ArchiveThread(char* to);
446   void FreeThreadResources();
447
448   // Garbage collection support.
449   void Iterate(v8::internal::ObjectVisitor* v);
450   static char* Iterate(v8::internal::ObjectVisitor* v, char* data);
451
452
453   inline internal::Object** GetSpareOrNewBlock();
454   inline void DeleteExtensions(internal::Object** prev_limit);
455
456   inline void IncrementCallDepth() {call_depth_++;}
457   inline void DecrementCallDepth() {call_depth_--;}
458   inline bool CallDepthIsZero() { return call_depth_ == 0; }
459
460   inline void EnterContext(Handle<Object> context);
461   inline bool LeaveLastContext();
462
463   // Returns the last entered context or an empty handle if no
464   // contexts have been entered.
465   inline Handle<Object> LastEnteredContext();
466
467   inline void SaveContext(Context* context);
468   inline Context* RestoreContext();
469   inline bool HasSavedContexts();
470
471   inline List<internal::Object**>* blocks() { return &blocks_; }
472   Isolate* isolate() const { return isolate_; }
473
474  private:
475   void ResetAfterArchive() {
476     blocks_.Initialize(0);
477     entered_contexts_.Initialize(0);
478     saved_contexts_.Initialize(0);
479     spare_ = NULL;
480     deferred_handles_head_ = NULL;
481     last_handle_before_deferred_block_ = NULL;
482     call_depth_ = 0;
483   }
484
485   void Free() {
486     ASSERT(blocks_.length() == 0);
487     ASSERT(entered_contexts_.length() == 0);
488     ASSERT(saved_contexts_.length() == 0);
489     ASSERT(deferred_handles_head_ == NULL);
490     blocks_.Free();
491     entered_contexts_.Free();
492     saved_contexts_.Free();
493     if (spare_ != NULL) {
494       DeleteArray(spare_);
495       spare_ = NULL;
496     }
497     ASSERT(call_depth_ == 0);
498   }
499
500   void BeginDeferredScope();
501   DeferredHandles* Detach(Object** prev_limit);
502   void DestroyDeferredHandles(DeferredHandles* handles);
503
504   Isolate* isolate_;
505   List<internal::Object**> blocks_;
506   // Used as a stack to keep track of entered contexts.
507   List<Handle<Object> > entered_contexts_;
508   // Used as a stack to keep track of saved contexts.
509   List<Context*> saved_contexts_;
510   Object** spare_;
511   int call_depth_;
512   Object** last_handle_before_deferred_block_;
513   DeferredHandles* deferred_handles_head_;
514   // This is only used for threading support.
515   v8::ImplementationUtilities::HandleScopeData handle_scope_data_;
516
517   void IterateThis(ObjectVisitor* v);
518   char* RestoreThreadHelper(char* from);
519   char* ArchiveThreadHelper(char* to);
520
521   friend class DeferredHandles;
522   friend class DeferredHandleScope;
523
524   DISALLOW_COPY_AND_ASSIGN(HandleScopeImplementer);
525 };
526
527
528 const int kHandleBlockSize = v8::internal::KB - 2;  // fit in one page
529
530
531 void HandleScopeImplementer::SaveContext(Context* context) {
532   saved_contexts_.Add(context);
533 }
534
535
536 Context* HandleScopeImplementer::RestoreContext() {
537   return saved_contexts_.RemoveLast();
538 }
539
540
541 bool HandleScopeImplementer::HasSavedContexts() {
542   return !saved_contexts_.is_empty();
543 }
544
545
546 void HandleScopeImplementer::EnterContext(Handle<Object> context) {
547   entered_contexts_.Add(context);
548 }
549
550
551 bool HandleScopeImplementer::LeaveLastContext() {
552   if (entered_contexts_.is_empty()) return false;
553   entered_contexts_.RemoveLast();
554   return true;
555 }
556
557
558 Handle<Object> HandleScopeImplementer::LastEnteredContext() {
559   if (entered_contexts_.is_empty()) return Handle<Object>::null();
560   return entered_contexts_.last();
561 }
562
563
564 // If there's a spare block, use it for growing the current scope.
565 internal::Object** HandleScopeImplementer::GetSpareOrNewBlock() {
566   internal::Object** block = (spare_ != NULL) ?
567       spare_ :
568       NewArray<internal::Object*>(kHandleBlockSize);
569   spare_ = NULL;
570   return block;
571 }
572
573
574 void HandleScopeImplementer::DeleteExtensions(internal::Object** prev_limit) {
575   while (!blocks_.is_empty()) {
576     internal::Object** block_start = blocks_.last();
577     internal::Object** block_limit = block_start + kHandleBlockSize;
578 #ifdef DEBUG
579     // NoHandleAllocation may make the prev_limit to point inside the block.
580     if (block_start <= prev_limit && prev_limit <= block_limit) break;
581 #else
582     if (prev_limit == block_limit) break;
583 #endif
584
585     blocks_.RemoveLast();
586 #ifdef DEBUG
587     v8::ImplementationUtilities::ZapHandleRange(block_start, block_limit);
588 #endif
589     if (spare_ != NULL) {
590       DeleteArray(spare_);
591     }
592     spare_ = block_start;
593   }
594   ASSERT((blocks_.is_empty() && prev_limit == NULL) ||
595          (!blocks_.is_empty() && prev_limit != NULL));
596 }
597
598
599 class Testing {
600  public:
601   static v8::Testing::StressType stress_type() { return stress_type_; }
602   static void set_stress_type(v8::Testing::StressType stress_type) {
603     stress_type_ = stress_type;
604   }
605
606  private:
607   static v8::Testing::StressType stress_type_;
608 };
609
610 } }  // namespace v8::internal
611
612 #endif  // V8_API_H_