| // Copyright 2012 the V8 project authors. All rights reserved. |
| // Redistribution and use in source and binary forms, with or without |
| // modification, are permitted provided that the following conditions are |
| // met: |
| // |
| // * Redistributions of source code must retain the above copyright |
| // notice, this list of conditions and the following disclaimer. |
| // * Redistributions in binary form must reproduce the above |
| // copyright notice, this list of conditions and the following |
| // disclaimer in the documentation and/or other materials provided |
| // with the distribution. |
| // * Neither the name of Google Inc. nor the names of its |
| // contributors may be used to endorse or promote products derived |
| // from this software without specific prior written permission. |
| // |
| // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
| // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
| // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR |
| // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT |
| // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
| // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT |
| // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
| // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
| // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
| // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| |
| #ifndef V8_HEAP_H_ |
| #define V8_HEAP_H_ |
| |
| #include <math.h> |
| |
| #include "allocation.h" |
| #include "globals.h" |
| #include "incremental-marking.h" |
| #include "list.h" |
| #include "mark-compact.h" |
| #include "objects-visiting.h" |
| #include "spaces.h" |
| #include "splay-tree-inl.h" |
| #include "store-buffer.h" |
| #include "v8-counters.h" |
| #include "v8globals.h" |
| |
| namespace v8 { |
| namespace internal { |
| |
| // Defines all the roots in Heap. |
| #define STRONG_ROOT_LIST(V) \ |
| V(Map, byte_array_map, ByteArrayMap) \ |
| V(Map, free_space_map, FreeSpaceMap) \ |
| V(Map, one_pointer_filler_map, OnePointerFillerMap) \ |
| V(Map, two_pointer_filler_map, TwoPointerFillerMap) \ |
| /* Cluster the most popular ones in a few cache lines here at the top. */ \ |
| V(Smi, store_buffer_top, StoreBufferTop) \ |
| V(Oddball, undefined_value, UndefinedValue) \ |
| V(Oddball, the_hole_value, TheHoleValue) \ |
| V(Oddball, null_value, NullValue) \ |
| V(Oddball, true_value, TrueValue) \ |
| V(Oddball, false_value, FalseValue) \ |
| V(Map, global_property_cell_map, GlobalPropertyCellMap) \ |
| V(Map, shared_function_info_map, SharedFunctionInfoMap) \ |
| V(Map, meta_map, MetaMap) \ |
| V(Map, ascii_symbol_map, AsciiSymbolMap) \ |
| V(Map, ascii_string_map, AsciiStringMap) \ |
| V(Map, heap_number_map, HeapNumberMap) \ |
| V(Map, native_context_map, NativeContextMap) \ |
| V(Map, fixed_array_map, FixedArrayMap) \ |
| V(Map, code_map, CodeMap) \ |
| V(Map, scope_info_map, ScopeInfoMap) \ |
| V(Map, fixed_cow_array_map, FixedCOWArrayMap) \ |
| V(Map, fixed_double_array_map, FixedDoubleArrayMap) \ |
| V(Object, no_interceptor_result_sentinel, NoInterceptorResultSentinel) \ |
| V(Map, hash_table_map, HashTableMap) \ |
| V(FixedArray, empty_fixed_array, EmptyFixedArray) \ |
| V(ByteArray, empty_byte_array, EmptyByteArray) \ |
| V(String, empty_string, EmptyString) \ |
| V(DescriptorArray, empty_descriptor_array, EmptyDescriptorArray) \ |
| V(Smi, stack_limit, StackLimit) \ |
| V(Oddball, arguments_marker, ArgumentsMarker) \ |
| /* The first 32 roots above this line should be boring from a GC point of */ \ |
| /* view. This means they are never in new space and never on a page that */ \ |
| /* is being compacted. */ \ |
| V(FixedArray, number_string_cache, NumberStringCache) \ |
| V(Object, instanceof_cache_function, InstanceofCacheFunction) \ |
| V(Object, instanceof_cache_map, InstanceofCacheMap) \ |
| V(Object, instanceof_cache_answer, InstanceofCacheAnswer) \ |
| V(FixedArray, single_character_string_cache, SingleCharacterStringCache) \ |
| V(FixedArray, string_split_cache, StringSplitCache) \ |
| V(FixedArray, regexp_multiple_cache, RegExpMultipleCache) \ |
| V(Object, termination_exception, TerminationException) \ |
| V(Smi, hash_seed, HashSeed) \ |
| V(Map, string_map, StringMap) \ |
| V(Map, symbol_map, SymbolMap) \ |
| V(Map, cons_string_map, ConsStringMap) \ |
| V(Map, cons_ascii_string_map, ConsAsciiStringMap) \ |
| V(Map, sliced_string_map, SlicedStringMap) \ |
| V(Map, sliced_ascii_string_map, SlicedAsciiStringMap) \ |
| V(Map, cons_symbol_map, ConsSymbolMap) \ |
| V(Map, cons_ascii_symbol_map, ConsAsciiSymbolMap) \ |
| V(Map, external_symbol_map, ExternalSymbolMap) \ |
| V(Map, external_symbol_with_ascii_data_map, ExternalSymbolWithAsciiDataMap) \ |
| V(Map, external_ascii_symbol_map, ExternalAsciiSymbolMap) \ |
| V(Map, external_string_map, ExternalStringMap) \ |
| V(Map, external_string_with_ascii_data_map, ExternalStringWithAsciiDataMap) \ |
| V(Map, external_ascii_string_map, ExternalAsciiStringMap) \ |
| V(Map, short_external_symbol_map, ShortExternalSymbolMap) \ |
| V(Map, \ |
| short_external_symbol_with_ascii_data_map, \ |
| ShortExternalSymbolWithAsciiDataMap) \ |
| V(Map, short_external_ascii_symbol_map, ShortExternalAsciiSymbolMap) \ |
| V(Map, short_external_string_map, ShortExternalStringMap) \ |
| V(Map, \ |
| short_external_string_with_ascii_data_map, \ |
| ShortExternalStringWithAsciiDataMap) \ |
| V(Map, short_external_ascii_string_map, ShortExternalAsciiStringMap) \ |
| V(Map, undetectable_string_map, UndetectableStringMap) \ |
| V(Map, undetectable_ascii_string_map, UndetectableAsciiStringMap) \ |
| V(Map, external_pixel_array_map, ExternalPixelArrayMap) \ |
| V(Map, external_byte_array_map, ExternalByteArrayMap) \ |
| V(Map, external_unsigned_byte_array_map, ExternalUnsignedByteArrayMap) \ |
| V(Map, external_short_array_map, ExternalShortArrayMap) \ |
| V(Map, external_unsigned_short_array_map, ExternalUnsignedShortArrayMap) \ |
| V(Map, external_int_array_map, ExternalIntArrayMap) \ |
| V(Map, external_unsigned_int_array_map, ExternalUnsignedIntArrayMap) \ |
| V(Map, external_float_array_map, ExternalFloatArrayMap) \ |
| V(Map, external_double_array_map, ExternalDoubleArrayMap) \ |
| V(Map, non_strict_arguments_elements_map, NonStrictArgumentsElementsMap) \ |
| V(Map, function_context_map, FunctionContextMap) \ |
| V(Map, catch_context_map, CatchContextMap) \ |
| V(Map, with_context_map, WithContextMap) \ |
| V(Map, block_context_map, BlockContextMap) \ |
| V(Map, module_context_map, ModuleContextMap) \ |
| V(Map, global_context_map, GlobalContextMap) \ |
| V(Map, oddball_map, OddballMap) \ |
| V(Map, message_object_map, JSMessageObjectMap) \ |
| V(Map, foreign_map, ForeignMap) \ |
| V(HeapNumber, nan_value, NanValue) \ |
| V(HeapNumber, infinity_value, InfinityValue) \ |
| V(HeapNumber, minus_zero_value, MinusZeroValue) \ |
| V(Map, neander_map, NeanderMap) \ |
| V(JSObject, message_listeners, MessageListeners) \ |
| V(Foreign, prototype_accessors, PrototypeAccessors) \ |
| V(UnseededNumberDictionary, code_stubs, CodeStubs) \ |
| V(UnseededNumberDictionary, non_monomorphic_cache, NonMonomorphicCache) \ |
| V(PolymorphicCodeCache, polymorphic_code_cache, PolymorphicCodeCache) \ |
| V(Code, js_entry_code, JsEntryCode) \ |
| V(Code, js_construct_entry_code, JsConstructEntryCode) \ |
| V(FixedArray, natives_source_cache, NativesSourceCache) \ |
| V(Object, last_script_id, LastScriptId) \ |
| V(Script, empty_script, EmptyScript) \ |
| V(Smi, real_stack_limit, RealStackLimit) \ |
| V(StringDictionary, intrinsic_function_names, IntrinsicFunctionNames) \ |
| V(Smi, arguments_adaptor_deopt_pc_offset, ArgumentsAdaptorDeoptPCOffset) \ |
| V(Smi, construct_stub_deopt_pc_offset, ConstructStubDeoptPCOffset) \ |
| V(Smi, getter_stub_deopt_pc_offset, GetterStubDeoptPCOffset) \ |
| V(Smi, setter_stub_deopt_pc_offset, SetterStubDeoptPCOffset) \ |
| V(JSObject, observation_state, ObservationState) \ |
| V(Map, external_map, ExternalMap) |
| |
| #define ROOT_LIST(V) \ |
| STRONG_ROOT_LIST(V) \ |
| V(SymbolTable, symbol_table, SymbolTable) |
| |
| #define SYMBOL_LIST(V) \ |
| V(Array_symbol, "Array") \ |
| V(Object_symbol, "Object") \ |
| V(Proto_symbol, "__proto__") \ |
| V(StringImpl_symbol, "StringImpl") \ |
| V(arguments_symbol, "arguments") \ |
| V(Arguments_symbol, "Arguments") \ |
| V(call_symbol, "call") \ |
| V(apply_symbol, "apply") \ |
| V(caller_symbol, "caller") \ |
| V(boolean_symbol, "boolean") \ |
| V(Boolean_symbol, "Boolean") \ |
| V(callee_symbol, "callee") \ |
| V(constructor_symbol, "constructor") \ |
| V(code_symbol, ".code") \ |
| V(result_symbol, ".result") \ |
| V(dot_for_symbol, ".for.") \ |
| V(catch_var_symbol, ".catch-var") \ |
| V(empty_symbol, "") \ |
| V(eval_symbol, "eval") \ |
| V(function_symbol, "function") \ |
| V(length_symbol, "length") \ |
| V(module_symbol, "module") \ |
| V(name_symbol, "name") \ |
| V(native_symbol, "native") \ |
| V(null_symbol, "null") \ |
| V(number_symbol, "number") \ |
| V(Number_symbol, "Number") \ |
| V(nan_symbol, "NaN") \ |
| V(RegExp_symbol, "RegExp") \ |
| V(source_symbol, "source") \ |
| V(global_symbol, "global") \ |
| V(ignore_case_symbol, "ignoreCase") \ |
| V(multiline_symbol, "multiline") \ |
| V(input_symbol, "input") \ |
| V(index_symbol, "index") \ |
| V(last_index_symbol, "lastIndex") \ |
| V(object_symbol, "object") \ |
| V(prototype_symbol, "prototype") \ |
| V(string_symbol, "string") \ |
| V(String_symbol, "String") \ |
| V(Date_symbol, "Date") \ |
| V(this_symbol, "this") \ |
| V(to_string_symbol, "toString") \ |
| V(char_at_symbol, "CharAt") \ |
| V(undefined_symbol, "undefined") \ |
| V(value_of_symbol, "valueOf") \ |
| V(stack_symbol, "stack") \ |
| V(InitializeVarGlobal_symbol, "InitializeVarGlobal") \ |
| V(InitializeConstGlobal_symbol, "InitializeConstGlobal") \ |
| V(KeyedLoadElementMonomorphic_symbol, \ |
| "KeyedLoadElementMonomorphic") \ |
| V(KeyedStoreElementMonomorphic_symbol, \ |
| "KeyedStoreElementMonomorphic") \ |
| V(KeyedStoreAndGrowElementMonomorphic_symbol, \ |
| "KeyedStoreAndGrowElementMonomorphic") \ |
| V(stack_overflow_symbol, "kStackOverflowBoilerplate") \ |
| V(illegal_access_symbol, "illegal access") \ |
| V(out_of_memory_symbol, "out-of-memory") \ |
| V(illegal_execution_state_symbol, "illegal execution state") \ |
| V(get_symbol, "get") \ |
| V(set_symbol, "set") \ |
| V(map_field_symbol, "%map") \ |
| V(elements_field_symbol, "%elements") \ |
| V(length_field_symbol, "%length") \ |
| V(function_class_symbol, "Function") \ |
| V(illegal_argument_symbol, "illegal argument") \ |
| V(MakeReferenceError_symbol, "MakeReferenceError") \ |
| V(MakeSyntaxError_symbol, "MakeSyntaxError") \ |
| V(MakeTypeError_symbol, "MakeTypeError") \ |
| V(invalid_lhs_in_assignment_symbol, "invalid_lhs_in_assignment") \ |
| V(invalid_lhs_in_for_in_symbol, "invalid_lhs_in_for_in") \ |
| V(invalid_lhs_in_postfix_op_symbol, "invalid_lhs_in_postfix_op") \ |
| V(invalid_lhs_in_prefix_op_symbol, "invalid_lhs_in_prefix_op") \ |
| V(illegal_return_symbol, "illegal_return") \ |
| V(illegal_break_symbol, "illegal_break") \ |
| V(illegal_continue_symbol, "illegal_continue") \ |
| V(unknown_label_symbol, "unknown_label") \ |
| V(redeclaration_symbol, "redeclaration") \ |
| V(failure_symbol, "<failure>") \ |
| V(space_symbol, " ") \ |
| V(exec_symbol, "exec") \ |
| V(zero_symbol, "0") \ |
| V(global_eval_symbol, "GlobalEval") \ |
| V(identity_hash_symbol, "v8::IdentityHash") \ |
| V(closure_symbol, "(closure)") \ |
| V(use_strict, "use strict") \ |
| V(dot_symbol, ".") \ |
| V(anonymous_function_symbol, "(anonymous function)") \ |
| V(compare_ic_symbol, "==") \ |
| V(strict_compare_ic_symbol, "===") \ |
| V(infinity_symbol, "Infinity") \ |
| V(minus_infinity_symbol, "-Infinity") \ |
| V(hidden_stack_trace_symbol, "v8::hidden_stack_trace") \ |
| V(query_colon_symbol, "(?:)") |
| |
| // Forward declarations. |
| class GCTracer; |
| class HeapStats; |
| class Isolate; |
| class WeakObjectRetainer; |
| |
| |
| typedef String* (*ExternalStringTableUpdaterCallback)(Heap* heap, |
| Object** pointer); |
| |
| class StoreBufferRebuilder { |
| public: |
| explicit StoreBufferRebuilder(StoreBuffer* store_buffer) |
| : store_buffer_(store_buffer) { |
| } |
| |
| void Callback(MemoryChunk* page, StoreBufferEvent event); |
| |
| private: |
| StoreBuffer* store_buffer_; |
| |
| // We record in this variable how full the store buffer was when we started |
| // iterating over the current page, finding pointers to new space. If the |
| // store buffer overflows again we can exempt the page from the store buffer |
| // by rewinding to this point instead of having to search the store buffer. |
| Object*** start_of_current_page_; |
| // The current page we are scanning in the store buffer iterator. |
| MemoryChunk* current_page_; |
| }; |
| |
| |
| |
| // A queue of objects promoted during scavenge. Each object is accompanied |
| // by it's size to avoid dereferencing a map pointer for scanning. |
| class PromotionQueue { |
| public: |
| explicit PromotionQueue(Heap* heap) |
| : front_(NULL), |
| rear_(NULL), |
| limit_(NULL), |
| emergency_stack_(0), |
| heap_(heap) { } |
| |
| void Initialize(); |
| |
| void Destroy() { |
| ASSERT(is_empty()); |
| delete emergency_stack_; |
| emergency_stack_ = NULL; |
| } |
| |
| inline void ActivateGuardIfOnTheSamePage(); |
| |
| Page* GetHeadPage() { |
| return Page::FromAllocationTop(reinterpret_cast<Address>(rear_)); |
| } |
| |
| void SetNewLimit(Address limit) { |
| if (!guard_) { |
| return; |
| } |
| |
| ASSERT(GetHeadPage() == Page::FromAllocationTop(limit)); |
| limit_ = reinterpret_cast<intptr_t*>(limit); |
| |
| if (limit_ <= rear_) { |
| return; |
| } |
| |
| RelocateQueueHead(); |
| } |
| |
| bool is_empty() { |
| return (front_ == rear_) && |
| (emergency_stack_ == NULL || emergency_stack_->length() == 0); |
| } |
| |
| inline void insert(HeapObject* target, int size); |
| |
| void remove(HeapObject** target, int* size) { |
| ASSERT(!is_empty()); |
| if (front_ == rear_) { |
| Entry e = emergency_stack_->RemoveLast(); |
| *target = e.obj_; |
| *size = e.size_; |
| return; |
| } |
| |
| if (NewSpacePage::IsAtStart(reinterpret_cast<Address>(front_))) { |
| NewSpacePage* front_page = |
| NewSpacePage::FromAddress(reinterpret_cast<Address>(front_)); |
| ASSERT(!front_page->prev_page()->is_anchor()); |
| front_ = |
| reinterpret_cast<intptr_t*>(front_page->prev_page()->area_end()); |
| } |
| *target = reinterpret_cast<HeapObject*>(*(--front_)); |
| *size = static_cast<int>(*(--front_)); |
| // Assert no underflow. |
| SemiSpace::AssertValidRange(reinterpret_cast<Address>(rear_), |
| reinterpret_cast<Address>(front_)); |
| } |
| |
| private: |
| // The front of the queue is higher in the memory page chain than the rear. |
| intptr_t* front_; |
| intptr_t* rear_; |
| intptr_t* limit_; |
| |
| bool guard_; |
| |
| static const int kEntrySizeInWords = 2; |
| |
| struct Entry { |
| Entry(HeapObject* obj, int size) : obj_(obj), size_(size) { } |
| |
| HeapObject* obj_; |
| int size_; |
| }; |
| List<Entry>* emergency_stack_; |
| |
| Heap* heap_; |
| |
| void RelocateQueueHead(); |
| |
| DISALLOW_COPY_AND_ASSIGN(PromotionQueue); |
| }; |
| |
| |
| typedef void (*ScavengingCallback)(Map* map, |
| HeapObject** slot, |
| HeapObject* object); |
| |
| |
| // External strings table is a place where all external strings are |
| // registered. We need to keep track of such strings to properly |
| // finalize them. |
| class ExternalStringTable { |
| public: |
| // Registers an external string. |
| inline void AddString(String* string); |
| |
| inline void Iterate(ObjectVisitor* v); |
| |
| // Restores internal invariant and gets rid of collected strings. |
| // Must be called after each Iterate() that modified the strings. |
| void CleanUp(); |
| |
| // Destroys all allocated memory. |
| void TearDown(); |
| |
| private: |
| ExternalStringTable() { } |
| |
| friend class Heap; |
| |
| inline void Verify(); |
| |
| inline void AddOldString(String* string); |
| |
| // Notifies the table that only a prefix of the new list is valid. |
| inline void ShrinkNewStrings(int position); |
| |
| // To speed up scavenge collections new space string are kept |
| // separate from old space strings. |
| List<Object*> new_space_strings_; |
| List<Object*> old_space_strings_; |
| |
| Heap* heap_; |
| |
| DISALLOW_COPY_AND_ASSIGN(ExternalStringTable); |
| }; |
| |
| |
| // The stack property of an error object is implemented as a getter that |
| // formats the attached raw stack trace into a string. This raw stack trace |
| // keeps code and function objects alive until the getter is called the first |
| // time. To release those objects, we call the getter after each GC for |
| // newly tenured error objects that are kept in a list. |
| class ErrorObjectList { |
| public: |
| inline void Add(JSObject* object); |
| |
| inline void Iterate(ObjectVisitor* v); |
| |
| void TearDown(); |
| |
| void RemoveUnmarked(Heap* heap); |
| |
| void DeferredFormatStackTrace(Isolate* isolate); |
| |
| void UpdateReferences(); |
| |
| void UpdateReferencesInNewSpace(Heap* heap); |
| |
| private: |
| static const int kBudgetPerGC = 16; |
| |
| ErrorObjectList() : nested_(false) { } |
| |
| friend class Heap; |
| |
| List<Object*> list_; |
| bool nested_; |
| |
| DISALLOW_COPY_AND_ASSIGN(ErrorObjectList); |
| }; |
| |
| |
| enum ArrayStorageAllocationMode { |
| DONT_INITIALIZE_ARRAY_ELEMENTS, |
| INITIALIZE_ARRAY_ELEMENTS_WITH_HOLE |
| }; |
| |
| class Heap { |
| public: |
| // Configure heap size before setup. Return false if the heap has been |
| // set up already. |
| bool ConfigureHeap(int max_semispace_size, |
| intptr_t max_old_gen_size, |
| intptr_t max_executable_size); |
| bool ConfigureHeapDefault(); |
| |
| // Initializes the global object heap. If create_heap_objects is true, |
| // also creates the basic non-mutable objects. |
| // Returns whether it succeeded. |
| bool SetUp(bool create_heap_objects); |
| |
| // Destroys all memory allocated by the heap. |
| void TearDown(); |
| |
| // Set the stack limit in the roots_ array. Some architectures generate |
| // code that looks here, because it is faster than loading from the static |
| // jslimit_/real_jslimit_ variable in the StackGuard. |
| void SetStackLimits(); |
| |
| // Returns whether SetUp has been called. |
| bool HasBeenSetUp(); |
| |
| // Returns the maximum amount of memory reserved for the heap. For |
| // the young generation, we reserve 4 times the amount needed for a |
| // semi space. The young generation consists of two semi spaces and |
| // we reserve twice the amount needed for those in order to ensure |
| // that new space can be aligned to its size. |
| intptr_t MaxReserved() { |
| return 4 * reserved_semispace_size_ + max_old_generation_size_; |
| } |
| int MaxSemiSpaceSize() { return max_semispace_size_; } |
| int ReservedSemiSpaceSize() { return reserved_semispace_size_; } |
| int InitialSemiSpaceSize() { return initial_semispace_size_; } |
| intptr_t MaxOldGenerationSize() { return max_old_generation_size_; } |
| intptr_t MaxExecutableSize() { return max_executable_size_; } |
| |
| // Returns the capacity of the heap in bytes w/o growing. Heap grows when |
| // more spaces are needed until it reaches the limit. |
| intptr_t Capacity(); |
| |
| // Returns the amount of memory currently committed for the heap. |
| intptr_t CommittedMemory(); |
| |
| // Returns the amount of executable memory currently committed for the heap. |
| intptr_t CommittedMemoryExecutable(); |
| |
| // Returns the amount of phyical memory currently committed for the heap. |
| size_t CommittedPhysicalMemory(); |
| |
| // Returns the available bytes in space w/o growing. |
| // Heap doesn't guarantee that it can allocate an object that requires |
| // all available bytes. Check MaxHeapObjectSize() instead. |
| intptr_t Available(); |
| |
| // Returns of size of all objects residing in the heap. |
| intptr_t SizeOfObjects(); |
| |
| // Return the starting address and a mask for the new space. And-masking an |
| // address with the mask will result in the start address of the new space |
| // for all addresses in either semispace. |
| Address NewSpaceStart() { return new_space_.start(); } |
| uintptr_t NewSpaceMask() { return new_space_.mask(); } |
| Address NewSpaceTop() { return new_space_.top(); } |
| |
| NewSpace* new_space() { return &new_space_; } |
| OldSpace* old_pointer_space() { return old_pointer_space_; } |
| OldSpace* old_data_space() { return old_data_space_; } |
| OldSpace* code_space() { return code_space_; } |
| MapSpace* map_space() { return map_space_; } |
| CellSpace* cell_space() { return cell_space_; } |
| LargeObjectSpace* lo_space() { return lo_space_; } |
| PagedSpace* paged_space(int idx) { |
| switch (idx) { |
| case OLD_POINTER_SPACE: |
| return old_pointer_space(); |
| case OLD_DATA_SPACE: |
| return old_data_space(); |
| case MAP_SPACE: |
| return map_space(); |
| case CELL_SPACE: |
| return cell_space(); |
| case CODE_SPACE: |
| return code_space(); |
| case NEW_SPACE: |
| case LO_SPACE: |
| UNREACHABLE(); |
| } |
| return NULL; |
| } |
| |
| bool always_allocate() { return always_allocate_scope_depth_ != 0; } |
| Address always_allocate_scope_depth_address() { |
| return reinterpret_cast<Address>(&always_allocate_scope_depth_); |
| } |
| bool linear_allocation() { |
| return linear_allocation_scope_depth_ != 0; |
| } |
| |
| Address* NewSpaceAllocationTopAddress() { |
| return new_space_.allocation_top_address(); |
| } |
| Address* NewSpaceAllocationLimitAddress() { |
| return new_space_.allocation_limit_address(); |
| } |
| |
| // Uncommit unused semi space. |
| bool UncommitFromSpace() { return new_space_.UncommitFromSpace(); } |
| |
| // Allocates and initializes a new JavaScript object based on a |
| // constructor. |
| // Returns Failure::RetryAfterGC(requested_bytes, space) if the allocation |
| // failed. |
| // Please note this does not perform a garbage collection. |
| MUST_USE_RESULT MaybeObject* AllocateJSObject( |
| JSFunction* constructor, PretenureFlag pretenure = NOT_TENURED); |
| |
| MUST_USE_RESULT MaybeObject* AllocateJSModule(Context* context, |
| ScopeInfo* scope_info); |
| |
| // Allocate a JSArray with no elements |
| MUST_USE_RESULT MaybeObject* AllocateEmptyJSArray( |
| ElementsKind elements_kind, |
| PretenureFlag pretenure = NOT_TENURED) { |
| return AllocateJSArrayAndStorage(elements_kind, 0, 0, |
| DONT_INITIALIZE_ARRAY_ELEMENTS, |
| pretenure); |
| } |
| |
| // Allocate a JSArray with a specified length but elements that are left |
| // uninitialized. |
| MUST_USE_RESULT MaybeObject* AllocateJSArrayAndStorage( |
| ElementsKind elements_kind, |
| int length, |
| int capacity, |
| ArrayStorageAllocationMode mode = DONT_INITIALIZE_ARRAY_ELEMENTS, |
| PretenureFlag pretenure = NOT_TENURED); |
| |
| // Allocate a JSArray with no elements |
| MUST_USE_RESULT MaybeObject* AllocateJSArrayWithElements( |
| FixedArrayBase* array_base, |
| ElementsKind elements_kind, |
| int length, |
| PretenureFlag pretenure = NOT_TENURED); |
| |
| // Allocates and initializes a new global object based on a constructor. |
| // Returns Failure::RetryAfterGC(requested_bytes, space) if the allocation |
| // failed. |
| // Please note this does not perform a garbage collection. |
| MUST_USE_RESULT MaybeObject* AllocateGlobalObject(JSFunction* constructor); |
| |
| // Returns a deep copy of the JavaScript object. |
| // Properties and elements are copied too. |
| // Returns failure if allocation failed. |
| MUST_USE_RESULT MaybeObject* CopyJSObject( |
| JSObject* source, |
| AllocationSiteMode mode = DONT_TRACK_ALLOCATION_SITE); |
| |
| // Allocates the function prototype. |
| // Returns Failure::RetryAfterGC(requested_bytes, space) if the allocation |
| // failed. |
| // Please note this does not perform a garbage collection. |
| MUST_USE_RESULT MaybeObject* AllocateFunctionPrototype(JSFunction* function); |
| |
| // Allocates a Harmony proxy or function proxy. |
| // Returns Failure::RetryAfterGC(requested_bytes, space) if the allocation |
| // failed. |
| // Please note this does not perform a garbage collection. |
| MUST_USE_RESULT MaybeObject* AllocateJSProxy(Object* handler, |
| Object* prototype); |
| |
| MUST_USE_RESULT MaybeObject* AllocateJSFunctionProxy(Object* handler, |
| Object* call_trap, |
| Object* construct_trap, |
| Object* prototype); |
| |
| // Reinitialize a JSReceiver into an (empty) JS object of respective type and |
| // size, but keeping the original prototype. The receiver must have at least |
| // the size of the new object. The object is reinitialized and behaves as an |
| // object that has been freshly allocated. |
| // Returns failure if an error occured, otherwise object. |
| MUST_USE_RESULT MaybeObject* ReinitializeJSReceiver(JSReceiver* object, |
| InstanceType type, |
| int size); |
| |
| // Reinitialize an JSGlobalProxy based on a constructor. The object |
| // must have the same size as objects allocated using the |
| // constructor. The object is reinitialized and behaves as an |
| // object that has been freshly allocated using the constructor. |
| MUST_USE_RESULT MaybeObject* ReinitializeJSGlobalProxy( |
| JSFunction* constructor, JSGlobalProxy* global); |
| |
| // Allocates and initializes a new JavaScript object based on a map. |
| // Returns Failure::RetryAfterGC(requested_bytes, space) if the allocation |
| // failed. |
| // Please note this does not perform a garbage collection. |
| MUST_USE_RESULT MaybeObject* AllocateJSObjectFromMap( |
| Map* map, PretenureFlag pretenure = NOT_TENURED); |
| |
| // Allocates a heap object based on the map. |
| // Returns Failure::RetryAfterGC(requested_bytes, space) if the allocation |
| // failed. |
| // Please note this function does not perform a garbage collection. |
| MUST_USE_RESULT MaybeObject* Allocate(Map* map, AllocationSpace space); |
| |
| // Allocates a JS Map in the heap. |
| // Returns Failure::RetryAfterGC(requested_bytes, space) if the allocation |
| // failed. |
| // Please note this function does not perform a garbage collection. |
| MUST_USE_RESULT MaybeObject* AllocateMap( |
| InstanceType instance_type, |
| int instance_size, |
| ElementsKind elements_kind = TERMINAL_FAST_ELEMENTS_KIND); |
| |
| // Allocates a partial map for bootstrapping. |
| MUST_USE_RESULT MaybeObject* AllocatePartialMap(InstanceType instance_type, |
| int instance_size); |
| |
| // Allocate a map for the specified function |
| MUST_USE_RESULT MaybeObject* AllocateInitialMap(JSFunction* fun); |
| |
| // Allocates an empty code cache. |
| MUST_USE_RESULT MaybeObject* AllocateCodeCache(); |
| |
| // Allocates a serialized scope info. |
| MUST_USE_RESULT MaybeObject* AllocateScopeInfo(int length); |
| |
| // Allocates an External object for v8's external API. |
| MUST_USE_RESULT MaybeObject* AllocateExternal(void* value); |
| |
| // Allocates an empty PolymorphicCodeCache. |
| MUST_USE_RESULT MaybeObject* AllocatePolymorphicCodeCache(); |
| |
| // Allocates a pre-tenured empty AccessorPair. |
| MUST_USE_RESULT MaybeObject* AllocateAccessorPair(); |
| |
| // Allocates an empty TypeFeedbackInfo. |
| MUST_USE_RESULT MaybeObject* AllocateTypeFeedbackInfo(); |
| |
| // Allocates an AliasedArgumentsEntry. |
| MUST_USE_RESULT MaybeObject* AllocateAliasedArgumentsEntry(int slot); |
| |
| // Clear the Instanceof cache (used when a prototype changes). |
| inline void ClearInstanceofCache(); |
| |
| // For use during bootup. |
| void RepairFreeListsAfterBoot(); |
| |
| // Allocates and fully initializes a String. There are two String |
| // encodings: ASCII and two byte. One should choose between the three string |
| // allocation functions based on the encoding of the string buffer used to |
| // initialized the string. |
| // - ...FromAscii initializes the string from a buffer that is ASCII |
| // encoded (it does not check that the buffer is ASCII encoded) and the |
| // result will be ASCII encoded. |
| // - ...FromUTF8 initializes the string from a buffer that is UTF-8 |
| // encoded. If the characters are all single-byte characters, the |
| // result will be ASCII encoded, otherwise it will converted to two |
| // byte. |
| // - ...FromTwoByte initializes the string from a buffer that is two-byte |
| // encoded. If the characters are all single-byte characters, the |
| // result will be converted to ASCII, otherwise it will be left as |
| // two-byte. |
| // Returns Failure::RetryAfterGC(requested_bytes, space) if the allocation |
| // failed. |
| // Please note this does not perform a garbage collection. |
| MUST_USE_RESULT MaybeObject* AllocateStringFromOneByte( |
| Vector<const uint8_t> str, |
| PretenureFlag pretenure = NOT_TENURED); |
| // TODO(dcarney): remove this function. |
| MUST_USE_RESULT inline MaybeObject* AllocateStringFromOneByte( |
| Vector<const char> str, |
| PretenureFlag pretenure = NOT_TENURED) { |
| return AllocateStringFromOneByte(Vector<const uint8_t>::cast(str), |
| pretenure); |
| } |
| MUST_USE_RESULT inline MaybeObject* AllocateStringFromUtf8( |
| Vector<const char> str, |
| PretenureFlag pretenure = NOT_TENURED); |
| MUST_USE_RESULT MaybeObject* AllocateStringFromUtf8Slow( |
| Vector<const char> str, |
| int non_ascii_start, |
| PretenureFlag pretenure = NOT_TENURED); |
| MUST_USE_RESULT MaybeObject* AllocateStringFromTwoByte( |
| Vector<const uc16> str, |
| PretenureFlag pretenure = NOT_TENURED); |
| |
| // Allocates a symbol in old space based on the character stream. |
| // Returns Failure::RetryAfterGC(requested_bytes, space) if the allocation |
| // failed. |
| // Please note this function does not perform a garbage collection. |
| MUST_USE_RESULT inline MaybeObject* AllocateSymbolFromUtf8( |
| Vector<const char> str, |
| int chars, |
| uint32_t hash_field); |
| |
| MUST_USE_RESULT inline MaybeObject* AllocateOneByteSymbol( |
| Vector<const uint8_t> str, |
| uint32_t hash_field); |
| |
| MUST_USE_RESULT inline MaybeObject* AllocateTwoByteSymbol( |
| Vector<const uc16> str, |
| uint32_t hash_field); |
| |
| template<typename T> |
| static inline bool IsOneByte(T t, int chars); |
| |
| template<typename T> |
| MUST_USE_RESULT inline MaybeObject* AllocateInternalSymbol( |
| T t, int chars, uint32_t hash_field); |
| |
| template<bool is_one_byte, typename T> |
| MUST_USE_RESULT MaybeObject* AllocateInternalSymbol( |
| T t, int chars, uint32_t hash_field); |
| |
| // Allocates and partially initializes a String. There are two String |
| // encodings: ASCII and two byte. These functions allocate a string of the |
| // given length and set its map and length fields. The characters of the |
| // string are uninitialized. |
| // Returns Failure::RetryAfterGC(requested_bytes, space) if the allocation |
| // failed. |
| // Please note this does not perform a garbage collection. |
| MUST_USE_RESULT MaybeObject* AllocateRawOneByteString( |
| int length, |
| PretenureFlag pretenure = NOT_TENURED); |
| MUST_USE_RESULT MaybeObject* AllocateRawTwoByteString( |
| int length, |
| PretenureFlag pretenure = NOT_TENURED); |
| |
| // Computes a single character string where the character has code. |
| // A cache is used for ASCII codes. |
| // Returns Failure::RetryAfterGC(requested_bytes, space) if the allocation |
| // failed. Please note this does not perform a garbage collection. |
| MUST_USE_RESULT MaybeObject* LookupSingleCharacterStringFromCode( |
| uint16_t code); |
| |
| // Allocate a byte array of the specified length |
| // Returns Failure::RetryAfterGC(requested_bytes, space) if the allocation |
| // failed. |
| // Please note this does not perform a garbage collection. |
| MUST_USE_RESULT MaybeObject* AllocateByteArray(int length, |
| PretenureFlag pretenure); |
| |
| // Allocate a non-tenured byte array of the specified length |
| // Returns Failure::RetryAfterGC(requested_bytes, space) if the allocation |
| // failed. |
| // Please note this does not perform a garbage collection. |
| MUST_USE_RESULT MaybeObject* AllocateByteArray(int length); |
| |
| // Allocates an external array of the specified length and type. |
| // Returns Failure::RetryAfterGC(requested_bytes, space) if the allocation |
| // failed. |
| // Please note this does not perform a garbage collection. |
| MUST_USE_RESULT MaybeObject* AllocateExternalArray( |
| int length, |
| ExternalArrayType array_type, |
| void* external_pointer, |
| PretenureFlag pretenure); |
| |
| // Allocate a tenured JS global property cell. |
| // Returns Failure::RetryAfterGC(requested_bytes, space) if the allocation |
| // failed. |
| // Please note this does not perform a garbage collection. |
| MUST_USE_RESULT MaybeObject* AllocateJSGlobalPropertyCell(Object* value); |
| |
| // Allocates a fixed array initialized with undefined values |
| // Returns Failure::RetryAfterGC(requested_bytes, space) if the allocation |
| // failed. |
| // Please note this does not perform a garbage collection. |
| MUST_USE_RESULT MaybeObject* AllocateFixedArray(int length, |
| PretenureFlag pretenure); |
| // Allocates a fixed array initialized with undefined values |
| MUST_USE_RESULT MaybeObject* AllocateFixedArray(int length); |
| |
| // Allocates an uninitialized fixed array. It must be filled by the caller. |
| // |
| // Returns Failure::RetryAfterGC(requested_bytes, space) if the allocation |
| // failed. |
| // Please note this does not perform a garbage collection. |
| MUST_USE_RESULT MaybeObject* AllocateUninitializedFixedArray(int length); |
| |
| // Move len elements within a given array from src_index index to dst_index |
| // index. |
| void MoveElements(FixedArray* array, int dst_index, int src_index, int len); |
| |
| // Make a copy of src and return it. Returns |
| // Failure::RetryAfterGC(requested_bytes, space) if the allocation failed. |
| MUST_USE_RESULT inline MaybeObject* CopyFixedArray(FixedArray* src); |
| |
| // Make a copy of src, set the map, and return the copy. Returns |
| // Failure::RetryAfterGC(requested_bytes, space) if the allocation failed. |
| MUST_USE_RESULT MaybeObject* CopyFixedArrayWithMap(FixedArray* src, Map* map); |
| |
| // Make a copy of src and return it. Returns |
| // Failure::RetryAfterGC(requested_bytes, space) if the allocation failed. |
| MUST_USE_RESULT inline MaybeObject* CopyFixedDoubleArray( |
| FixedDoubleArray* src); |
| |
| // Make a copy of src, set the map, and return the copy. Returns |
| // Failure::RetryAfterGC(requested_bytes, space) if the allocation failed. |
| MUST_USE_RESULT MaybeObject* CopyFixedDoubleArrayWithMap( |
| FixedDoubleArray* src, Map* map); |
| |
| // Allocates a fixed array initialized with the hole values. |
| // Returns Failure::RetryAfterGC(requested_bytes, space) if the allocation |
| // failed. |
| // Please note this does not perform a garbage collection. |
| MUST_USE_RESULT MaybeObject* AllocateFixedArrayWithHoles( |
| int length, |
| PretenureFlag pretenure = NOT_TENURED); |
| |
| MUST_USE_RESULT MaybeObject* AllocateRawFixedDoubleArray( |
| int length, |
| PretenureFlag pretenure); |
| |
| // Allocates a fixed double array with uninitialized values. Returns |
| // Failure::RetryAfterGC(requested_bytes, space) if the allocation failed. |
| // Please note this does not perform a garbage collection. |
| MUST_USE_RESULT MaybeObject* AllocateUninitializedFixedDoubleArray( |
| int length, |
| PretenureFlag pretenure = NOT_TENURED); |
| |
| // Allocates a fixed double array with hole values. Returns |
| // Failure::RetryAfterGC(requested_bytes, space) if the allocation failed. |
| // Please note this does not perform a garbage collection. |
| MUST_USE_RESULT MaybeObject* AllocateFixedDoubleArrayWithHoles( |
| int length, |
| PretenureFlag pretenure = NOT_TENURED); |
| |
| // AllocateHashTable is identical to AllocateFixedArray except |
| // that the resulting object has hash_table_map as map. |
| MUST_USE_RESULT MaybeObject* AllocateHashTable( |
| int length, PretenureFlag pretenure = NOT_TENURED); |
| |
| // Allocate a native (but otherwise uninitialized) context. |
| MUST_USE_RESULT MaybeObject* AllocateNativeContext(); |
| |
| // Allocate a global context. |
| MUST_USE_RESULT MaybeObject* AllocateGlobalContext(JSFunction* function, |
| ScopeInfo* scope_info); |
| |
| // Allocate a module context. |
| MUST_USE_RESULT MaybeObject* AllocateModuleContext(ScopeInfo* scope_info); |
| |
| // Allocate a function context. |
| MUST_USE_RESULT MaybeObject* AllocateFunctionContext(int length, |
| JSFunction* function); |
| |
| // Allocate a catch context. |
| MUST_USE_RESULT MaybeObject* AllocateCatchContext(JSFunction* function, |
| Context* previous, |
| String* name, |
| Object* thrown_object); |
| // Allocate a 'with' context. |
| MUST_USE_RESULT MaybeObject* AllocateWithContext(JSFunction* function, |
| Context* previous, |
| JSObject* extension); |
| |
| // Allocate a block context. |
| MUST_USE_RESULT MaybeObject* AllocateBlockContext(JSFunction* function, |
| Context* previous, |
| ScopeInfo* info); |
| |
| // Allocates a new utility object in the old generation. |
| MUST_USE_RESULT MaybeObject* AllocateStruct(InstanceType type); |
| |
| // Allocates a function initialized with a shared part. |
| // Returns Failure::RetryAfterGC(requested_bytes, space) if the allocation |
| // failed. |
| // Please note this does not perform a garbage collection. |
| MUST_USE_RESULT MaybeObject* AllocateFunction( |
| Map* function_map, |
| SharedFunctionInfo* shared, |
| Object* prototype, |
| PretenureFlag pretenure = TENURED); |
| |
| // Arguments object size. |
| static const int kArgumentsObjectSize = |
| JSObject::kHeaderSize + 2 * kPointerSize; |
| // Strict mode arguments has no callee so it is smaller. |
| static const int kArgumentsObjectSizeStrict = |
| JSObject::kHeaderSize + 1 * kPointerSize; |
| // Indicies for direct access into argument objects. |
| static const int kArgumentsLengthIndex = 0; |
| // callee is only valid in non-strict mode. |
| static const int kArgumentsCalleeIndex = 1; |
| |
| // Allocates an arguments object - optionally with an elements array. |
| // Returns Failure::RetryAfterGC(requested_bytes, space) if the allocation |
| // failed. |
| // Please note this does not perform a garbage collection. |
| MUST_USE_RESULT MaybeObject* AllocateArgumentsObject( |
| Object* callee, int length); |
| |
| // Same as NewNumberFromDouble, but may return a preallocated/immutable |
| // number object (e.g., minus_zero_value_, nan_value_) |
| MUST_USE_RESULT MaybeObject* NumberFromDouble( |
| double value, PretenureFlag pretenure = NOT_TENURED); |
| |
| // Allocated a HeapNumber from value. |
| MUST_USE_RESULT MaybeObject* AllocateHeapNumber( |
| double value, |
| PretenureFlag pretenure); |
| // pretenure = NOT_TENURED |
| MUST_USE_RESULT MaybeObject* AllocateHeapNumber(double value); |
| |
| // Converts an int into either a Smi or a HeapNumber object. |
| // Returns Failure::RetryAfterGC(requested_bytes, space) if the allocation |
| // failed. |
| // Please note this does not perform a garbage collection. |
| MUST_USE_RESULT inline MaybeObject* NumberFromInt32( |
| int32_t value, PretenureFlag pretenure = NOT_TENURED); |
| |
| // Converts an int into either a Smi or a HeapNumber object. |
| // Returns Failure::RetryAfterGC(requested_bytes, space) if the allocation |
| // failed. |
| // Please note this does not perform a garbage collection. |
| MUST_USE_RESULT inline MaybeObject* NumberFromUint32( |
| uint32_t value, PretenureFlag pretenure = NOT_TENURED); |
| |
| // Allocates a new foreign object. |
| // Returns Failure::RetryAfterGC(requested_bytes, space) if the allocation |
| // failed. |
| // Please note this does not perform a garbage collection. |
| MUST_USE_RESULT MaybeObject* AllocateForeign( |
| Address address, PretenureFlag pretenure = NOT_TENURED); |
| |
| // Allocates a new SharedFunctionInfo object. |
| // Returns Failure::RetryAfterGC(requested_bytes, space) if the allocation |
| // failed. |
| // Please note this does not perform a garbage collection. |
| MUST_USE_RESULT MaybeObject* AllocateSharedFunctionInfo(Object* name); |
| |
| // Allocates a new JSMessageObject object. |
| // Returns Failure::RetryAfterGC(requested_bytes, space) if the allocation |
| // failed. |
| // Please note that this does not perform a garbage collection. |
| MUST_USE_RESULT MaybeObject* AllocateJSMessageObject( |
| String* type, |
| JSArray* arguments, |
| int start_position, |
| int end_position, |
| Object* script, |
| Object* stack_trace, |
| Object* stack_frames); |
| |
| // Allocates a new cons string object. |
| // Returns Failure::RetryAfterGC(requested_bytes, space) if the allocation |
| // failed. |
| // Please note this does not perform a garbage collection. |
| MUST_USE_RESULT MaybeObject* AllocateConsString(String* first, |
| String* second); |
| |
| // Allocates a new sub string object which is a substring of an underlying |
| // string buffer stretching from the index start (inclusive) to the index |
| // end (exclusive). |
| // Returns Failure::RetryAfterGC(requested_bytes, space) if the allocation |
| // failed. |
| // Please note this does not perform a garbage collection. |
| MUST_USE_RESULT MaybeObject* AllocateSubString( |
| String* buffer, |
| int start, |
| int end, |
| PretenureFlag pretenure = NOT_TENURED); |
| |
| // Allocate a new external string object, which is backed by a string |
| // resource that resides outside the V8 heap. |
| // Returns Failure::RetryAfterGC(requested_bytes, space) if the allocation |
| // failed. |
| // Please note this does not perform a garbage collection. |
| MUST_USE_RESULT MaybeObject* AllocateExternalStringFromAscii( |
| const ExternalAsciiString::Resource* resource); |
| MUST_USE_RESULT MaybeObject* AllocateExternalStringFromTwoByte( |
| const ExternalTwoByteString::Resource* resource); |
| |
| // Finalizes an external string by deleting the associated external |
| // data and clearing the resource pointer. |
| inline void FinalizeExternalString(String* string); |
| |
| // Allocates an uninitialized object. The memory is non-executable if the |
| // hardware and OS allow. |
| // Returns Failure::RetryAfterGC(requested_bytes, space) if the allocation |
| // failed. |
| // Please note this function does not perform a garbage collection. |
| MUST_USE_RESULT inline MaybeObject* AllocateRaw(int size_in_bytes, |
| AllocationSpace space, |
| AllocationSpace retry_space); |
| |
| // Initialize a filler object to keep the ability to iterate over the heap |
| // when shortening objects. |
| void CreateFillerObjectAt(Address addr, int size); |
| |
| // Makes a new native code object |
| // Returns Failure::RetryAfterGC(requested_bytes, space) if the allocation |
| // failed. On success, the pointer to the Code object is stored in the |
| // self_reference. This allows generated code to reference its own Code |
| // object by containing this pointer. |
| // Please note this function does not perform a garbage collection. |
| MUST_USE_RESULT MaybeObject* CreateCode(const CodeDesc& desc, |
| Code::Flags flags, |
| Handle<Object> self_reference, |
| bool immovable = false); |
| |
| MUST_USE_RESULT MaybeObject* CopyCode(Code* code); |
| |
| // Copy the code and scope info part of the code object, but insert |
| // the provided data as the relocation information. |
| MUST_USE_RESULT MaybeObject* CopyCode(Code* code, Vector<byte> reloc_info); |
| |
| // Finds the symbol for string in the symbol table. |
| // If not found, a new symbol is added to the table and returned. |
| // Returns Failure::RetryAfterGC(requested_bytes, space) if allocation |
| // failed. |
| // Please note this function does not perform a garbage collection. |
| MUST_USE_RESULT MaybeObject* LookupUtf8Symbol(Vector<const char> str); |
| MUST_USE_RESULT MaybeObject* LookupUtf8Symbol(const char* str) { |
| return LookupUtf8Symbol(CStrVector(str)); |
| } |
| MUST_USE_RESULT MaybeObject* LookupOneByteSymbol(Vector<const uint8_t> str); |
| MUST_USE_RESULT MaybeObject* LookupTwoByteSymbol(Vector<const uc16> str); |
| MUST_USE_RESULT MaybeObject* LookupSymbol(String* str); |
| MUST_USE_RESULT MaybeObject* LookupOneByteSymbol( |
| Handle<SeqOneByteString> string, int from, int length); |
| |
| bool LookupSymbolIfExists(String* str, String** symbol); |
| bool LookupTwoCharsSymbolIfExists(String* str, String** symbol); |
| |
| // Compute the matching symbol map for a string if possible. |
| // NULL is returned if string is in new space or not flattened. |
| Map* SymbolMapForString(String* str); |
| |
| // Tries to flatten a string before compare operation. |
| // |
| // Returns a failure in case it was decided that flattening was |
| // necessary and failed. Note, if flattening is not necessary the |
| // string might stay non-flat even when not a failure is returned. |
| // |
| // Please note this function does not perform a garbage collection. |
| MUST_USE_RESULT inline MaybeObject* PrepareForCompare(String* str); |
| |
| // Converts the given boolean condition to JavaScript boolean value. |
| inline Object* ToBoolean(bool condition); |
| |
| // Code that should be run before and after each GC. Includes some |
| // reporting/verification activities when compiled with DEBUG set. |
| void GarbageCollectionPrologue(); |
| void GarbageCollectionEpilogue(); |
| |
| // Performs garbage collection operation. |
| // Returns whether there is a chance that another major GC could |
| // collect more garbage. |
| bool CollectGarbage(AllocationSpace space, |
| GarbageCollector collector, |
| const char* gc_reason, |
| const char* collector_reason); |
| |
| // Performs garbage collection operation. |
| // Returns whether there is a chance that another major GC could |
| // collect more garbage. |
| inline bool CollectGarbage(AllocationSpace space, |
| const char* gc_reason = NULL); |
| |
| static const int kNoGCFlags = 0; |
| static const int kSweepPreciselyMask = 1; |
| static const int kReduceMemoryFootprintMask = 2; |
| static const int kAbortIncrementalMarkingMask = 4; |
| |
| // Making the heap iterable requires us to sweep precisely and abort any |
| // incremental marking as well. |
| static const int kMakeHeapIterableMask = |
| kSweepPreciselyMask | kAbortIncrementalMarkingMask; |
| |
| // Performs a full garbage collection. If (flags & kMakeHeapIterableMask) is |
| // non-zero, then the slower precise sweeper is used, which leaves the heap |
| // in a state where we can iterate over the heap visiting all objects. |
| void CollectAllGarbage(int flags, const char* gc_reason = NULL); |
| |
| // Last hope GC, should try to squeeze as much as possible. |
| void CollectAllAvailableGarbage(const char* gc_reason = NULL); |
| |
| // Check whether the heap is currently iterable. |
| bool IsHeapIterable(); |
| |
| // Ensure that we have swept all spaces in such a way that we can iterate |
| // over all objects. May cause a GC. |
| void EnsureHeapIsIterable(); |
| |
| // Notify the heap that a context has been disposed. |
| int NotifyContextDisposed() { |
| flush_monomorphic_ics_ = true; |
| return ++contexts_disposed_; |
| } |
| |
| // Utility to invoke the scavenger. This is needed in test code to |
| // ensure correct callback for weak global handles. |
| void PerformScavenge(); |
| |
| inline void increment_scan_on_scavenge_pages() { |
| scan_on_scavenge_pages_++; |
| if (FLAG_gc_verbose) { |
| PrintF("Scan-on-scavenge pages: %d\n", scan_on_scavenge_pages_); |
| } |
| } |
| |
| inline void decrement_scan_on_scavenge_pages() { |
| scan_on_scavenge_pages_--; |
| if (FLAG_gc_verbose) { |
| PrintF("Scan-on-scavenge pages: %d\n", scan_on_scavenge_pages_); |
| } |
| } |
| |
| PromotionQueue* promotion_queue() { return &promotion_queue_; } |
| |
| #ifdef DEBUG |
| // Utility used with flag gc-greedy. |
| void GarbageCollectionGreedyCheck(); |
| #endif |
| |
| void AddGCPrologueCallback( |
| GCPrologueCallback callback, GCType gc_type_filter); |
| void RemoveGCPrologueCallback(GCPrologueCallback callback); |
| |
| void AddGCEpilogueCallback( |
| GCEpilogueCallback callback, GCType gc_type_filter); |
| void RemoveGCEpilogueCallback(GCEpilogueCallback callback); |
| |
| void SetGlobalGCPrologueCallback(GCCallback callback) { |
| ASSERT((callback == NULL) ^ (global_gc_prologue_callback_ == NULL)); |
| global_gc_prologue_callback_ = callback; |
| } |
| void SetGlobalGCEpilogueCallback(GCCallback callback) { |
| ASSERT((callback == NULL) ^ (global_gc_epilogue_callback_ == NULL)); |
| global_gc_epilogue_callback_ = callback; |
| } |
| |
| // Heap root getters. We have versions with and without type::cast() here. |
| // You can't use type::cast during GC because the assert fails. |
| // TODO(1490): Try removing the unchecked accessors, now that GC marking does |
| // not corrupt the map. |
| #define ROOT_ACCESSOR(type, name, camel_name) \ |
| type* name() { \ |
| return type::cast(roots_[k##camel_name##RootIndex]); \ |
| } \ |
| type* raw_unchecked_##name() { \ |
| return reinterpret_cast<type*>(roots_[k##camel_name##RootIndex]); \ |
| } |
| ROOT_LIST(ROOT_ACCESSOR) |
| #undef ROOT_ACCESSOR |
| |
| // Utility type maps |
| #define STRUCT_MAP_ACCESSOR(NAME, Name, name) \ |
| Map* name##_map() { \ |
| return Map::cast(roots_[k##Name##MapRootIndex]); \ |
| } |
| STRUCT_LIST(STRUCT_MAP_ACCESSOR) |
| #undef STRUCT_MAP_ACCESSOR |
| |
| #define SYMBOL_ACCESSOR(name, str) String* name() { \ |
| return String::cast(roots_[k##name##RootIndex]); \ |
| } |
| SYMBOL_LIST(SYMBOL_ACCESSOR) |
| #undef SYMBOL_ACCESSOR |
| |
| // The hidden_symbol is special because it is the empty string, but does |
| // not match the empty string. |
| String* hidden_symbol() { return hidden_symbol_; } |
| |
| void set_native_contexts_list(Object* object) { |
| native_contexts_list_ = object; |
| } |
| Object* native_contexts_list() { return native_contexts_list_; } |
| |
| // Number of mark-sweeps. |
| unsigned int ms_count() { return ms_count_; } |
| |
| // Iterates over all roots in the heap. |
| void IterateRoots(ObjectVisitor* v, VisitMode mode); |
| // Iterates over all strong roots in the heap. |
| void IterateStrongRoots(ObjectVisitor* v, VisitMode mode); |
| // Iterates over all the other roots in the heap. |
| void IterateWeakRoots(ObjectVisitor* v, VisitMode mode); |
| |
| // Iterate pointers to from semispace of new space found in memory interval |
| // from start to end. |
| void IterateAndMarkPointersToFromSpace(Address start, |
| Address end, |
| ObjectSlotCallback callback); |
| |
| // Returns whether the object resides in new space. |
| inline bool InNewSpace(Object* object); |
| inline bool InNewSpace(Address addr); |
| inline bool InNewSpacePage(Address addr); |
| inline bool InFromSpace(Object* object); |
| inline bool InToSpace(Object* object); |
| |
| // Checks whether an address/object in the heap (including auxiliary |
| // area and unused area). |
| bool Contains(Address addr); |
| bool Contains(HeapObject* value); |
| |
| // Checks whether an address/object in a space. |
| // Currently used by tests, serialization and heap verification only. |
| bool InSpace(Address addr, AllocationSpace space); |
| bool InSpace(HeapObject* value, AllocationSpace space); |
| |
| // Finds out which space an object should get promoted to based on its type. |
| inline OldSpace* TargetSpace(HeapObject* object); |
| inline AllocationSpace TargetSpaceId(InstanceType type); |
| |
| // Sets the stub_cache_ (only used when expanding the dictionary). |
| void public_set_code_stubs(UnseededNumberDictionary* value) { |
| roots_[kCodeStubsRootIndex] = value; |
| } |
| |
| // Support for computing object sizes for old objects during GCs. Returns |
| // a function that is guaranteed to be safe for computing object sizes in |
| // the current GC phase. |
| HeapObjectCallback GcSafeSizeOfOldObjectFunction() { |
| return gc_safe_size_of_old_object_; |
| } |
| |
| // Sets the non_monomorphic_cache_ (only used when expanding the dictionary). |
| void public_set_non_monomorphic_cache(UnseededNumberDictionary* value) { |
| roots_[kNonMonomorphicCacheRootIndex] = value; |
| } |
| |
| void public_set_empty_script(Script* script) { |
| roots_[kEmptyScriptRootIndex] = script; |
| } |
| |
| void public_set_store_buffer_top(Address* top) { |
| roots_[kStoreBufferTopRootIndex] = reinterpret_cast<Smi*>(top); |
| } |
| |
| // Update the next script id. |
| inline void SetLastScriptId(Object* last_script_id); |
| |
| // Generated code can embed this address to get access to the roots. |
| Object** roots_array_start() { return roots_; } |
| |
| Address* store_buffer_top_address() { |
| return reinterpret_cast<Address*>(&roots_[kStoreBufferTopRootIndex]); |
| } |
| |
| // Get address of native contexts list for serialization support. |
| Object** native_contexts_list_address() { |
| return &native_contexts_list_; |
| } |
| |
| #ifdef VERIFY_HEAP |
| // Verify the heap is in its normal state before or after a GC. |
| void Verify(); |
| |
| |
| bool weak_embedded_maps_verification_enabled() { |
| return no_weak_embedded_maps_verification_scope_depth_ == 0; |
| } |
| #endif |
| |
| #ifdef DEBUG |
| void Print(); |
| void PrintHandles(); |
| |
| void OldPointerSpaceCheckStoreBuffer(); |
| void MapSpaceCheckStoreBuffer(); |
| void LargeObjectSpaceCheckStoreBuffer(); |
| |
| // Report heap statistics. |
| void ReportHeapStatistics(const char* title); |
| void ReportCodeStatistics(const char* title); |
| #endif |
| |
| // Zapping is needed for verify heap, and always done in debug builds. |
| static inline bool ShouldZapGarbage() { |
| #ifdef DEBUG |
| return true; |
| #else |
| #ifdef VERIFY_HEAP |
| return FLAG_verify_heap; |
| #else |
| return false; |
| #endif |
| #endif |
| } |
| |
| // Fill in bogus values in from space |
| void ZapFromSpace(); |
| |
| // Print short heap statistics. |
| void PrintShortHeapStatistics(); |
| |
| // Makes a new symbol object |
| // Returns Failure::RetryAfterGC(requested_bytes, space) if the allocation |
| // failed. |
| // Please note this function does not perform a garbage collection. |
| MUST_USE_RESULT MaybeObject* CreateSymbol( |
| const char* str, int length, int hash); |
| MUST_USE_RESULT MaybeObject* CreateSymbol(String* str); |
| |
| // Write barrier support for address[offset] = o. |
| inline void RecordWrite(Address address, int offset); |
| |
| // Write barrier support for address[start : start + len[ = o. |
| inline void RecordWrites(Address address, int start, int len); |
| |
| // Given an address occupied by a live code object, return that object. |
| Object* FindCodeObject(Address a); |
| |
| // Invoke Shrink on shrinkable spaces. |
| void Shrink(); |
| |
| enum HeapState { NOT_IN_GC, SCAVENGE, MARK_COMPACT }; |
| inline HeapState gc_state() { return gc_state_; } |
| |
| inline bool IsInGCPostProcessing() { return gc_post_processing_depth_ > 0; } |
| |
| #ifdef DEBUG |
| bool IsAllocationAllowed() { return allocation_allowed_; } |
| inline bool allow_allocation(bool enable); |
| |
| bool disallow_allocation_failure() { |
| return disallow_allocation_failure_; |
| } |
| |
| void TracePathToObjectFrom(Object* target, Object* root); |
| void TracePathToObject(Object* target); |
| void TracePathToGlobal(); |
| #endif |
| |
| // Callback function passed to Heap::Iterate etc. Copies an object if |
| // necessary, the object might be promoted to an old space. The caller must |
| // ensure the precondition that the object is (a) a heap object and (b) in |
| // the heap's from space. |
| static inline void ScavengePointer(HeapObject** p); |
| static inline void ScavengeObject(HeapObject** p, HeapObject* object); |
| |
| // Commits from space if it is uncommitted. |
| void EnsureFromSpaceIsCommitted(); |
| |
| // Support for partial snapshots. After calling this we have a linear |
| // space to write objects in each space. |
| void ReserveSpace(int *sizes, Address* addresses); |
| |
| // |
| // Support for the API. |
| // |
| |
| bool CreateApiObjects(); |
| |
| // Attempt to find the number in a small cache. If we finds it, return |
| // the string representation of the number. Otherwise return undefined. |
| Object* GetNumberStringCache(Object* number); |
| |
| // Update the cache with a new number-string pair. |
| void SetNumberStringCache(Object* number, String* str); |
| |
| // Adjusts the amount of registered external memory. |
| // Returns the adjusted value. |
| inline intptr_t AdjustAmountOfExternalAllocatedMemory( |
| intptr_t change_in_bytes); |
| |
| // Allocate uninitialized fixed array. |
| MUST_USE_RESULT MaybeObject* AllocateRawFixedArray(int length); |
| MUST_USE_RESULT MaybeObject* AllocateRawFixedArray(int length, |
| PretenureFlag pretenure); |
| |
| inline intptr_t PromotedTotalSize() { |
| return PromotedSpaceSizeOfObjects() + PromotedExternalMemorySize(); |
| } |
| |
| // True if we have reached the allocation limit in the old generation that |
| // should force the next GC (caused normally) to be a full one. |
| inline bool OldGenerationPromotionLimitReached() { |
| return PromotedTotalSize() > old_gen_promotion_limit_; |
| } |
| |
| inline intptr_t OldGenerationSpaceAvailable() { |
| return old_gen_allocation_limit_ - PromotedTotalSize(); |
| } |
| |
| inline intptr_t OldGenerationCapacityAvailable() { |
| return max_old_generation_size_ - PromotedTotalSize(); |
| } |
| |
| static const intptr_t kMinimumPromotionLimit = 5 * Page::kPageSize; |
| static const intptr_t kMinimumAllocationLimit = |
| 8 * (Page::kPageSize > MB ? Page::kPageSize : MB); |
| |
| intptr_t OldGenPromotionLimit(intptr_t old_gen_size) { |
| const int divisor = FLAG_stress_compaction ? 10 : 3; |
| intptr_t limit = |
| Max(old_gen_size + old_gen_size / divisor, kMinimumPromotionLimit); |
| limit += new_space_.Capacity(); |
| limit *= old_gen_limit_factor_; |
| intptr_t halfway_to_the_max = (old_gen_size + max_old_generation_size_) / 2; |
| return Min(limit, halfway_to_the_max); |
| } |
| |
| intptr_t OldGenAllocationLimit(intptr_t old_gen_size) { |
| const int divisor = FLAG_stress_compaction ? 8 : 2; |
| intptr_t limit = |
| Max(old_gen_size + old_gen_size / divisor, kMinimumAllocationLimit); |
| limit += new_space_.Capacity(); |
| limit *= old_gen_limit_factor_; |
| intptr_t halfway_to_the_max = (old_gen_size + max_old_generation_size_) / 2; |
| return Min(limit, halfway_to_the_max); |
| } |
| |
| // Implements the corresponding V8 API function. |
| bool IdleNotification(int hint); |
| |
| // Declare all the root indices. |
| enum RootListIndex { |
| #define ROOT_INDEX_DECLARATION(type, name, camel_name) k##camel_name##RootIndex, |
| STRONG_ROOT_LIST(ROOT_INDEX_DECLARATION) |
| #undef ROOT_INDEX_DECLARATION |
| |
| #define SYMBOL_INDEX_DECLARATION(name, str) k##name##RootIndex, |
| SYMBOL_LIST(SYMBOL_INDEX_DECLARATION) |
| #undef SYMBOL_DECLARATION |
| |
| // Utility type maps |
| #define DECLARE_STRUCT_MAP(NAME, Name, name) k##Name##MapRootIndex, |
| STRUCT_LIST(DECLARE_STRUCT_MAP) |
| #undef DECLARE_STRUCT_MAP |
| |
| kSymbolTableRootIndex, |
| kStrongRootListLength = kSymbolTableRootIndex, |
| kRootListLength |
| }; |
| |
| STATIC_CHECK(kUndefinedValueRootIndex == Internals::kUndefinedValueRootIndex); |
| STATIC_CHECK(kNullValueRootIndex == Internals::kNullValueRootIndex); |
| STATIC_CHECK(kTrueValueRootIndex == Internals::kTrueValueRootIndex); |
| STATIC_CHECK(kFalseValueRootIndex == Internals::kFalseValueRootIndex); |
| STATIC_CHECK(kempty_symbolRootIndex == Internals::kEmptySymbolRootIndex); |
| |
| // Generated code can embed direct references to non-writable roots if |
| // they are in new space. |
| static bool RootCanBeWrittenAfterInitialization(RootListIndex root_index); |
| |
| MUST_USE_RESULT MaybeObject* NumberToString( |
| Object* number, bool check_number_string_cache = true); |
| MUST_USE_RESULT MaybeObject* Uint32ToString( |
| uint32_t value, bool check_number_string_cache = true); |
| |
| Map* MapForExternalArrayType(ExternalArrayType array_type); |
| RootListIndex RootIndexForExternalArrayType( |
| ExternalArrayType array_type); |
| |
| void RecordStats(HeapStats* stats, bool take_snapshot = false); |
| |
| // Copy block of memory from src to dst. Size of block should be aligned |
| // by pointer size. |
| static inline void CopyBlock(Address dst, Address src, int byte_size); |
| |
| // Optimized version of memmove for blocks with pointer size aligned sizes and |
| // pointer size aligned addresses. |
| static inline void MoveBlock(Address dst, Address src, int byte_size); |
| |
| // Check new space expansion criteria and expand semispaces if it was hit. |
| void CheckNewSpaceExpansionCriteria(); |
| |
| inline void IncrementYoungSurvivorsCounter(int survived) { |
| ASSERT(survived >= 0); |
| young_survivors_after_last_gc_ = survived; |
| survived_since_last_expansion_ += survived; |
| } |
| |
| inline bool NextGCIsLikelyToBeFull() { |
| if (FLAG_gc_global) return true; |
| |
| if (FLAG_stress_compaction && (gc_count_ & 1) != 0) return true; |
| |
| intptr_t total_promoted = PromotedTotalSize(); |
| |
| intptr_t adjusted_promotion_limit = |
| old_gen_promotion_limit_ - new_space_.Capacity(); |
| |
| if (total_promoted >= adjusted_promotion_limit) return true; |
| |
| intptr_t adjusted_allocation_limit = |
| old_gen_allocation_limit_ - new_space_.Capacity() / 5; |
| |
| if (PromotedSpaceSizeOfObjects() >= adjusted_allocation_limit) return true; |
| |
| return false; |
| } |
| |
| |
| void UpdateNewSpaceReferencesInExternalStringTable( |
| ExternalStringTableUpdaterCallback updater_func); |
| |
| void UpdateReferencesInExternalStringTable( |
| ExternalStringTableUpdaterCallback updater_func); |
| |
| void ProcessWeakReferences(WeakObjectRetainer* retainer); |
| |
| void VisitExternalResources(v8::ExternalResourceVisitor* visitor); |
| |
| // Helper function that governs the promotion policy from new space to |
| // old. If the object's old address lies below the new space's age |
| // mark or if we've already filled the bottom 1/16th of the to space, |
| // we try to promote this object. |
| inline bool ShouldBePromoted(Address old_address, int object_size); |
| |
| int MaxObjectSizeInNewSpace() { return kMaxObjectSizeInNewSpace; } |
| |
| void ClearJSFunctionResultCaches(); |
| |
| void ClearNormalizedMapCaches(); |
| |
| GCTracer* tracer() { return tracer_; } |
| |
| // Returns the size of objects residing in non new spaces. |
| intptr_t PromotedSpaceSizeOfObjects(); |
| |
| double total_regexp_code_generated() { return total_regexp_code_generated_; } |
| void IncreaseTotalRegexpCodeGenerated(int size) { |
| total_regexp_code_generated_ += size; |
| } |
| |
| // Returns maximum GC pause. |
| double get_max_gc_pause() { return max_gc_pause_; } |
| |
| // Returns maximum size of objects alive after GC. |
| intptr_t get_max_alive_after_gc() { return max_alive_after_gc_; } |
| |
| // Returns minimal interval between two subsequent collections. |
| double get_min_in_mutator() { return min_in_mutator_; } |
| |
| // TODO(hpayer): remove, should be handled by GCTracer |
| void AddMarkingTime(double marking_time) { |
| marking_time_ += marking_time; |
| } |
| |
| double marking_time() const { |
| return marking_time_; |
| } |
| |
| // TODO(hpayer): remove, should be handled by GCTracer |
| void AddSweepingTime(double sweeping_time) { |
| sweeping_time_ += sweeping_time; |
| } |
| |
| double sweeping_time() const { |
| return sweeping_time_; |
| } |
| |
| MarkCompactCollector* mark_compact_collector() { |
| return &mark_compact_collector_; |
| } |
| |
| StoreBuffer* store_buffer() { |
| return &store_buffer_; |
| } |
| |
| Marking* marking() { |
| return &marking_; |
| } |
| |
| IncrementalMarking* incremental_marking() { |
| return &incremental_marking_; |
| } |
| |
| bool IsSweepingComplete() { |
| return !mark_compact_collector()->IsConcurrentSweepingInProgress() && |
| old_data_space()->IsLazySweepingComplete() && |
| old_pointer_space()->IsLazySweepingComplete(); |
| } |
| |
| bool AdvanceSweepers(int step_size) { |
| ASSERT(!FLAG_parallel_sweeping && !FLAG_concurrent_sweeping); |
| bool sweeping_complete = old_data_space()->AdvanceSweeper(step_size); |
| sweeping_complete &= old_pointer_space()->AdvanceSweeper(step_size); |
| return sweeping_complete; |
| } |
| |
| ExternalStringTable* external_string_table() { |
| return &external_string_table_; |
| } |
| |
| ErrorObjectList* error_object_list() { |
| return &error_object_list_; |
| } |
| |
| // Returns the current sweep generation. |
| int sweep_generation() { |
| return sweep_generation_; |
| } |
| |
| inline Isolate* isolate(); |
| |
| void CallGCPrologueCallbacks(GCType gc_type); |
| void CallGCEpilogueCallbacks(GCType gc_type); |
| |
| inline bool OldGenerationAllocationLimitReached(); |
| |
| inline void DoScavengeObject(Map* map, HeapObject** slot, HeapObject* obj) { |
| scavenging_visitors_table_.GetVisitor(map)(map, slot, obj); |
| } |
| |
| void QueueMemoryChunkForFree(MemoryChunk* chunk); |
| void FreeQueuedChunks(); |
| |
| // Completely clear the Instanceof cache (to stop it keeping objects alive |
| // around a GC). |
| inline void CompletelyClearInstanceofCache(); |
| |
| // The roots that have an index less than this are always in old space. |
| static const int kOldSpaceRoots = 0x20; |
| |
| uint32_t HashSeed() { |
| uint32_t seed = static_cast<uint32_t>(hash_seed()->value()); |
| ASSERT(FLAG_randomize_hashes || seed == 0); |
| return seed; |
| } |
| |
| void SetArgumentsAdaptorDeoptPCOffset(int pc_offset) { |
| ASSERT(arguments_adaptor_deopt_pc_offset() == Smi::FromInt(0)); |
| set_arguments_adaptor_deopt_pc_offset(Smi::FromInt(pc_offset)); |
| } |
| |
| void SetConstructStubDeoptPCOffset(int pc_offset) { |
| ASSERT(construct_stub_deopt_pc_offset() == Smi::FromInt(0)); |
| set_construct_stub_deopt_pc_offset(Smi::FromInt(pc_offset)); |
| } |
| |
| void SetGetterStubDeoptPCOffset(int pc_offset) { |
| ASSERT(getter_stub_deopt_pc_offset() == Smi::FromInt(0)); |
| set_getter_stub_deopt_pc_offset(Smi::FromInt(pc_offset)); |
| } |
| |
| void SetSetterStubDeoptPCOffset(int pc_offset) { |
| ASSERT(setter_stub_deopt_pc_offset() == Smi::FromInt(0)); |
| set_setter_stub_deopt_pc_offset(Smi::FromInt(pc_offset)); |
| } |
| |
| // For post mortem debugging. |
| void RememberUnmappedPage(Address page, bool compacted); |
| |
| // Global inline caching age: it is incremented on some GCs after context |
| // disposal. We use it to flush inline caches. |
| int global_ic_age() { |
| return global_ic_age_; |
| } |
| |
| void AgeInlineCaches() { |
| global_ic_age_ = (global_ic_age_ + 1) & SharedFunctionInfo::ICAgeBits::kMax; |
| } |
| |
| bool flush_monomorphic_ics() { return flush_monomorphic_ics_; } |
| |
| intptr_t amount_of_external_allocated_memory() { |
| return amount_of_external_allocated_memory_; |
| } |
| |
| // ObjectStats are kept in two arrays, counts and sizes. Related stats are |
| // stored in a contiguous linear buffer. Stats groups are stored one after |
| // another. |
| enum { |
| FIRST_CODE_KIND_SUB_TYPE = LAST_TYPE + 1, |
| FIRST_FIXED_ARRAY_SUB_TYPE = |
| FIRST_CODE_KIND_SUB_TYPE + Code::LAST_CODE_KIND + 1, |
| OBJECT_STATS_COUNT = |
| FIRST_FIXED_ARRAY_SUB_TYPE + LAST_FIXED_ARRAY_SUB_TYPE + 1 |
| }; |
| |
| void RecordObjectStats(InstanceType type, int sub_type, size_t size) { |
| ASSERT(type <= LAST_TYPE); |
| if (sub_type < 0) { |
| object_counts_[type]++; |
| object_sizes_[type] += size; |
| } else { |
| if (type == CODE_TYPE) { |
| ASSERT(sub_type <= Code::LAST_CODE_KIND); |
| object_counts_[FIRST_CODE_KIND_SUB_TYPE + sub_type]++; |
| object_sizes_[FIRST_CODE_KIND_SUB_TYPE + sub_type] += size; |
| } else if (type == FIXED_ARRAY_TYPE) { |
| ASSERT(sub_type <= LAST_FIXED_ARRAY_SUB_TYPE); |
| object_counts_[FIRST_FIXED_ARRAY_SUB_TYPE + sub_type]++; |
| object_sizes_[FIRST_FIXED_ARRAY_SUB_TYPE + sub_type] += size; |
| } |
| } |
| } |
| |
| void CheckpointObjectStats(); |
| |
| // We don't use a ScopedLock here since we want to lock the heap |
| // only when FLAG_parallel_recompilation is true. |
| class RelocationLock { |
| public: |
| explicit RelocationLock(Heap* heap) : heap_(heap) { |
| if (FLAG_parallel_recompilation) { |
| heap_->relocation_mutex_->Lock(); |
| } |
| } |
| ~RelocationLock() { |
| if (FLAG_parallel_recompilation) { |
| heap_->relocation_mutex_->Unlock(); |
| } |
| } |
| |
| private: |
| Heap* heap_; |
| }; |
| |
| private: |
| Heap(); |
| |
| // This can be calculated directly from a pointer to the heap; however, it is |
| // more expedient to get at the isolate directly from within Heap methods. |
| Isolate* isolate_; |
| |
| Object* roots_[kRootListLength]; |
| |
| intptr_t code_range_size_; |
| int reserved_semispace_size_; |
| int max_semispace_size_; |
| int initial_semispace_size_; |
| intptr_t max_old_generation_size_; |
| intptr_t max_executable_size_; |
| |
| // For keeping track of how much data has survived |
| // scavenge since last new space expansion. |
| int survived_since_last_expansion_; |
| |
| // For keeping track on when to flush RegExp code. |
| int sweep_generation_; |
| |
| int always_allocate_scope_depth_; |
| int linear_allocation_scope_depth_; |
| |
| // For keeping track of context disposals. |
| int contexts_disposed_; |
| |
| int global_ic_age_; |
| |
| bool flush_monomorphic_ics_; |
| |
| int scan_on_scavenge_pages_; |
| |
| #if defined(V8_TARGET_ARCH_X64) |
| static const int kMaxObjectSizeInNewSpace = 1024*KB; |
| #else |
| static const int kMaxObjectSizeInNewSpace = 512*KB; |
| #endif |
| |
| NewSpace new_space_; |
| OldSpace* old_pointer_space_; |
| OldSpace* old_data_space_; |
| OldSpace* code_space_; |
| MapSpace* map_space_; |
| CellSpace* cell_space_; |
| LargeObjectSpace* lo_space_; |
| HeapState gc_state_; |
| int gc_post_processing_depth_; |
| |
| // Returns the amount of external memory registered since last global gc. |
| intptr_t PromotedExternalMemorySize(); |
| |
| unsigned int ms_count_; // how many mark-sweep collections happened |
| unsigned int gc_count_; // how many gc happened |
| |
| // For post mortem debugging. |
| static const int kRememberedUnmappedPages = 128; |
| int remembered_unmapped_pages_index_; |
| Address remembered_unmapped_pages_[kRememberedUnmappedPages]; |
| |
| // Total length of the strings we failed to flatten since the last GC. |
| int unflattened_strings_length_; |
| |
| #define ROOT_ACCESSOR(type, name, camel_name) \ |
| inline void set_##name(type* value) { \ |
| /* The deserializer makes use of the fact that these common roots are */ \ |
| /* never in new space and never on a page that is being compacted. */ \ |
| ASSERT(k##camel_name##RootIndex >= kOldSpaceRoots || !InNewSpace(value)); \ |
| roots_[k##camel_name##RootIndex] = value; \ |
| } |
| ROOT_LIST(ROOT_ACCESSOR) |
| #undef ROOT_ACCESSOR |
| |
| #ifdef DEBUG |
| bool allocation_allowed_; |
| |
| // If the --gc-interval flag is set to a positive value, this |
| // variable holds the value indicating the number of allocations |
| // remain until the next failure and garbage collection. |
| int allocation_timeout_; |
| |
| // Do we expect to be able to handle allocation failure at this |
| // time? |
| bool disallow_allocation_failure_; |
| #endif // DEBUG |
| |
| // Indicates that the new space should be kept small due to high promotion |
| // rates caused by the mutator allocating a lot of long-lived objects. |
| bool new_space_high_promotion_mode_active_; |
| |
| // Limit that triggers a global GC on the next (normally caused) GC. This |
| // is checked when we have already decided to do a GC to help determine |
| // which collector to invoke. |
| intptr_t old_gen_promotion_limit_; |
| |
| // Limit that triggers a global GC as soon as is reasonable. This is |
| // checked before expanding a paged space in the old generation and on |
| // every allocation in large object space. |
| intptr_t old_gen_allocation_limit_; |
| |
| // Sometimes the heuristics dictate that those limits are increased. This |
| // variable records that fact. |
| int old_gen_limit_factor_; |
| |
| // Used to adjust the limits that control the timing of the next GC. |
| intptr_t size_of_old_gen_at_last_old_space_gc_; |
| |
| // Limit on the amount of externally allocated memory allowed |
| // between global GCs. If reached a global GC is forced. |
| intptr_t external_allocation_limit_; |
| |
| // The amount of external memory registered through the API kept alive |
| // by global handles |
| intptr_t amount_of_external_allocated_memory_; |
| |
| // Caches the amount of external memory registered at the last global gc. |
| intptr_t amount_of_external_allocated_memory_at_last_global_gc_; |
| |
| // Indicates that an allocation has failed in the old generation since the |
| // last GC. |
| int old_gen_exhausted_; |
| |
| Object* native_contexts_list_; |
| |
| StoreBufferRebuilder store_buffer_rebuilder_; |
| |
| struct StringTypeTable { |
| InstanceType type; |
| int size; |
| RootListIndex index; |
| }; |
| |
| struct ConstantSymbolTable { |
| const char* contents; |
| RootListIndex index; |
| }; |
| |
| struct StructTable { |
| InstanceType type; |
| int size; |
| RootListIndex index; |
| }; |
| |
| static const StringTypeTable string_type_table[]; |
| static const ConstantSymbolTable constant_symbol_table[]; |
| static const StructTable struct_table[]; |
| |
| // The special hidden symbol which is an empty string, but does not match |
| // any string when looked up in properties. |
| String* hidden_symbol_; |
| |
| // GC callback function, called before and after mark-compact GC. |
| // Allocations in the callback function are disallowed. |
| struct GCPrologueCallbackPair { |
| GCPrologueCallbackPair(GCPrologueCallback callback, GCType gc_type) |
| : callback(callback), gc_type(gc_type) { |
| } |
| bool operator==(const GCPrologueCallbackPair& pair) const { |
| return pair.callback == callback; |
| } |
| GCPrologueCallback callback; |
| GCType gc_type; |
| }; |
| List<GCPrologueCallbackPair> gc_prologue_callbacks_; |
| |
| struct GCEpilogueCallbackPair { |
| GCEpilogueCallbackPair(GCEpilogueCallback callback, GCType gc_type) |
| : callback(callback), gc_type(gc_type) { |
| } |
| bool operator==(const GCEpilogueCallbackPair& pair) const { |
| return pair.callback == callback; |
| } |
| GCEpilogueCallback callback; |
| GCType gc_type; |
| }; |
| List<GCEpilogueCallbackPair> gc_epilogue_callbacks_; |
| |
| GCCallback global_gc_prologue_callback_; |
| GCCallback global_gc_epilogue_callback_; |
| |
| // Support for computing object sizes during GC. |
| HeapObjectCallback gc_safe_size_of_old_object_; |
| static int GcSafeSizeOfOldObject(HeapObject* object); |
| |
| // Update the GC state. Called from the mark-compact collector. |
| void MarkMapPointersAsEncoded(bool encoded) { |
| ASSERT(!encoded); |
| gc_safe_size_of_old_object_ = &GcSafeSizeOfOldObject; |
| } |
| |
| // Checks whether a global GC is necessary |
| GarbageCollector SelectGarbageCollector(AllocationSpace space, |
| const char** reason); |
| |
| // Performs garbage collection |
| // Returns whether there is a chance another major GC could |
| // collect more garbage. |
| bool PerformGarbageCollection(GarbageCollector collector, |
| GCTracer* tracer); |
| |
| inline void UpdateOldSpaceLimits(); |
| |
| // Allocate an uninitialized object in map space. The behavior is identical |
| // to Heap::AllocateRaw(size_in_bytes, MAP_SPACE), except that (a) it doesn't |
| // have to test the allocation space argument and (b) can reduce code size |
| // (since both AllocateRaw and AllocateRawMap are inlined). |
| MUST_USE_RESULT inline MaybeObject* AllocateRawMap(); |
| |
| // Allocate an uninitialized object in the global property cell space. |
| MUST_USE_RESULT inline MaybeObject* AllocateRawCell(); |
| |
| // Initializes a JSObject based on its map. |
| void InitializeJSObjectFromMap(JSObject* obj, |
| FixedArray* properties, |
| Map* map); |
| |
| bool CreateInitialMaps(); |
| bool CreateInitialObjects(); |
| |
| // These five Create*EntryStub functions are here and forced to not be inlined |
| // because of a gcc-4.4 bug that assigns wrong vtable entries. |
| NO_INLINE(void CreateJSEntryStub()); |
| NO_INLINE(void CreateJSConstructEntryStub()); |
| |
| void CreateFixedStubs(); |
| |
| MUST_USE_RESULT MaybeObject* CreateOddball(const char* to_string, |
| Object* to_number, |
| byte kind); |
| |
| // Allocate a JSArray with no elements |
| MUST_USE_RESULT MaybeObject* AllocateJSArray( |
| ElementsKind elements_kind, |
| PretenureFlag pretenure = NOT_TENURED); |
| |
| // Allocate empty fixed array. |
| MUST_USE_RESULT MaybeObject* AllocateEmptyFixedArray(); |
| |
| // Allocate empty fixed double array. |
| MUST_USE_RESULT MaybeObject* AllocateEmptyFixedDoubleArray(); |
| |
| // Performs a minor collection in new generation. |
| void Scavenge(); |
| |
| static String* UpdateNewSpaceReferenceInExternalStringTableEntry( |
| Heap* heap, |
| Object** pointer); |
| |
| Address DoScavenge(ObjectVisitor* scavenge_visitor, Address new_space_front); |
| static void ScavengeStoreBufferCallback(Heap* heap, |
| MemoryChunk* page, |
| StoreBufferEvent event); |
| |
| // Performs a major collection in the whole heap. |
| void MarkCompact(GCTracer* tracer); |
| |
| // Code to be run before and after mark-compact. |
| void MarkCompactPrologue(); |
| |
| // Record statistics before and after garbage collection. |
| void ReportStatisticsBeforeGC(); |
| void ReportStatisticsAfterGC(); |
| |
| // Slow part of scavenge object. |
| static void ScavengeObjectSlow(HeapObject** p, HeapObject* object); |
| |
| // Initializes a function with a shared part and prototype. |
| // Note: this code was factored out of AllocateFunction such that |
| // other parts of the VM could use it. Specifically, a function that creates |
| // instances of type JS_FUNCTION_TYPE benefit from the use of this function. |
| // Please note this does not perform a garbage collection. |
| inline void InitializeFunction( |
| JSFunction* function, |
| SharedFunctionInfo* shared, |
| Object* prototype); |
| |
| // Total RegExp code ever generated |
| double total_regexp_code_generated_; |
| |
| GCTracer* tracer_; |
| |
| // Allocates a small number to string cache. |
| MUST_USE_RESULT MaybeObject* AllocateInitialNumberStringCache(); |
| // Creates and installs the full-sized number string cache. |
| void AllocateFullSizeNumberStringCache(); |
| // Get the length of the number to string cache based on the max semispace |
| // size. |
| int FullSizeNumberStringCacheLength(); |
| // Flush the number to string cache. |
| void FlushNumberStringCache(); |
| |
| void UpdateSurvivalRateTrend(int start_new_space_size); |
| |
| enum SurvivalRateTrend { INCREASING, STABLE, DECREASING, FLUCTUATING }; |
| |
| static const int kYoungSurvivalRateHighThreshold = 90; |
| static const int kYoungSurvivalRateLowThreshold = 10; |
| static const int kYoungSurvivalRateAllowedDeviation = 15; |
| |
| int young_survivors_after_last_gc_; |
| int high_survival_rate_period_length_; |
| int low_survival_rate_period_length_; |
| double survival_rate_; |
| SurvivalRateTrend previous_survival_rate_trend_; |
| SurvivalRateTrend survival_rate_trend_; |
| |
| void set_survival_rate_trend(SurvivalRateTrend survival_rate_trend) { |
| ASSERT(survival_rate_trend != FLUCTUATING); |
| previous_survival_rate_trend_ = survival_rate_trend_; |
| survival_rate_trend_ = survival_rate_trend; |
| } |
| |
| SurvivalRateTrend survival_rate_trend() { |
| if (survival_rate_trend_ == STABLE) { |
| return STABLE; |
| } else if (previous_survival_rate_trend_ == STABLE) { |
| return survival_rate_trend_; |
| } else if (survival_rate_trend_ != previous_survival_rate_trend_) { |
| return FLUCTUATING; |
| } else { |
| return survival_rate_trend_; |
| } |
| } |
| |
| bool IsStableOrIncreasingSurvivalTrend() { |
| switch (survival_rate_trend()) { |
| case STABLE: |
| case INCREASING: |
| return true; |
| default: |
| return false; |
| } |
| } |
| |
| bool IsStableOrDecreasingSurvivalTrend() { |
| switch (survival_rate_trend()) { |
| case STABLE: |
| case DECREASING: |
| return true; |
| default: |
| return false; |
| } |
| } |
| |
| bool IsIncreasingSurvivalTrend() { |
| return survival_rate_trend() == INCREASING; |
| } |
| |
| bool IsHighSurvivalRate() { |
| return high_survival_rate_period_length_ > 0; |
| } |
| |
| bool IsLowSurvivalRate() { |
| return low_survival_rate_period_length_ > 0; |
| } |
| |
| void SelectScavengingVisitorsTable(); |
| |
| void StartIdleRound() { |
| mark_sweeps_since_idle_round_started_ = 0; |
| ms_count_at_last_idle_notification_ = ms_count_; |
| } |
| |
| void FinishIdleRound() { |
| mark_sweeps_since_idle_round_started_ = kMaxMarkSweepsInIdleRound; |
| scavenges_since_last_idle_round_ = 0; |
| } |
| |
| bool EnoughGarbageSinceLastIdleRound() { |
| return (scavenges_since_last_idle_round_ >= kIdleScavengeThreshold); |
| } |
| |
| // Estimates how many milliseconds a Mark-Sweep would take to complete. |
| // In idle notification handler we assume that this function will return: |
| // - a number less than 10 for small heaps, which are less than 8Mb. |
| // - a number greater than 10 for large heaps, which are greater than 32Mb. |
| int TimeMarkSweepWouldTakeInMs() { |
| // Rough estimate of how many megabytes of heap can be processed in 1 ms. |
| static const int kMbPerMs = 2; |
| |
| int heap_size_mb = static_cast<int>(SizeOfObjects() / MB); |
| return heap_size_mb / kMbPerMs; |
| } |
| |
| // Returns true if no more GC work is left. |
| bool IdleGlobalGC(); |
| |
| void AdvanceIdleIncrementalMarking(intptr_t step_size); |
| |
| void ClearObjectStats(bool clear_last_time_stats = false); |
| |
| static const int kInitialSymbolTableSize = 2048; |
| static const int kInitialEvalCacheSize = 64; |
| static const int kInitialNumberStringCacheSize = 256; |
| |
| // Object counts and used memory by InstanceType |
| size_t object_counts_[OBJECT_STATS_COUNT]; |
| size_t object_counts_last_time_[OBJECT_STATS_COUNT]; |
| size_t object_sizes_[OBJECT_STATS_COUNT]; |
| size_t object_sizes_last_time_[OBJECT_STATS_COUNT]; |
| |
| // Maximum GC pause. |
| double max_gc_pause_; |
| |
| // Total time spent in GC. |
| double total_gc_time_ms_; |
| |
| // Maximum size of objects alive after GC. |
| intptr_t max_alive_after_gc_; |
| |
| // Minimal interval between two subsequent collections. |
| double min_in_mutator_; |
| |
| // Size of objects alive after last GC. |
| intptr_t alive_after_last_gc_; |
| |
| double last_gc_end_timestamp_; |
| |
| // Cumulative GC time spent in marking |
| double marking_time_; |
| |
| // Cumulative GC time spent in sweeping |
| double sweeping_time_; |
| |
| MarkCompactCollector mark_compact_collector_; |
| |
| StoreBuffer store_buffer_; |
| |
| Marking marking_; |
| |
| IncrementalMarking incremental_marking_; |
| |
| int number_idle_notifications_; |
| unsigned int last_idle_notification_gc_count_; |
| bool last_idle_notification_gc_count_init_; |
| |
| int mark_sweeps_since_idle_round_started_; |
| int ms_count_at_last_idle_notification_; |
| unsigned int gc_count_at_last_idle_gc_; |
| int scavenges_since_last_idle_round_; |
| |
| #ifdef VERIFY_HEAP |
| int no_weak_embedded_maps_verification_scope_depth_; |
| #endif |
| |
| static const int kMaxMarkSweepsInIdleRound = 7; |
| static const int kIdleScavengeThreshold = 5; |
| |
| // Shared state read by the scavenge collector and set by ScavengeObject. |
| PromotionQueue promotion_queue_; |
| |
| // Flag is set when the heap has been configured. The heap can be repeatedly |
| // configured through the API until it is set up. |
| bool configured_; |
| |
| ExternalStringTable external_string_table_; |
| |
| ErrorObjectList error_object_list_; |
| |
| VisitorDispatchTable<ScavengingCallback> scavenging_visitors_table_; |
| |
| MemoryChunk* chunks_queued_for_free_; |
| |
| Mutex* relocation_mutex_; |
| |
| friend class Factory; |
| friend class GCTracer; |
| friend class DisallowAllocationFailure; |
| friend class AlwaysAllocateScope; |
| friend class Page; |
| friend class Isolate; |
| friend class MarkCompactCollector; |
| friend class MarkCompactMarkingVisitor; |
| friend class MapCompact; |
| #ifdef VERIFY_HEAP |
| friend class NoWeakEmbeddedMapsVerificationScope; |
| #endif |
| |
| DISALLOW_COPY_AND_ASSIGN(Heap); |
| }; |
| |
| |
| class HeapStats { |
| public: |
| static const int kStartMarker = 0xDECADE00; |
| static const int kEndMarker = 0xDECADE01; |
| |
| int* start_marker; // 0 |
| int* new_space_size; // 1 |
| int* new_space_capacity; // 2 |
| intptr_t* old_pointer_space_size; // 3 |
| intptr_t* old_pointer_space_capacity; // 4 |
| intptr_t* old_data_space_size; // 5 |
| intptr_t* old_data_space_capacity; // 6 |
| intptr_t* code_space_size; // 7 |
| intptr_t* code_space_capacity; // 8 |
| intptr_t* map_space_size; // 9 |
| intptr_t* map_space_capacity; // 10 |
| intptr_t* cell_space_size; // 11 |
| intptr_t* cell_space_capacity; // 12 |
| intptr_t* lo_space_size; // 13 |
| int* global_handle_count; // 14 |
| int* weak_global_handle_count; // 15 |
| int* pending_global_handle_count; // 16 |
| int* near_death_global_handle_count; // 17 |
| int* free_global_handle_count; // 18 |
| intptr_t* memory_allocator_size; // 19 |
| intptr_t* memory_allocator_capacity; // 20 |
| int* objects_per_type; // 21 |
| int* size_per_type; // 22 |
| int* os_error; // 23 |
| int* end_marker; // 24 |
| }; |
| |
| |
| class DisallowAllocationFailure { |
| public: |
| inline DisallowAllocationFailure(); |
| inline ~DisallowAllocationFailure(); |
| |
| #ifdef DEBUG |
| private: |
| bool old_state_; |
| #endif |
| }; |
| |
| |
| class AlwaysAllocateScope { |
| public: |
| inline AlwaysAllocateScope(); |
| inline ~AlwaysAllocateScope(); |
| |
| private: |
| // Implicitly disable artificial allocation failures. |
| DisallowAllocationFailure disallow_allocation_failure_; |
| }; |
| |
| #ifdef VERIFY_HEAP |
| class NoWeakEmbeddedMapsVerificationScope { |
| public: |
| inline NoWeakEmbeddedMapsVerificationScope(); |
| inline ~NoWeakEmbeddedMapsVerificationScope(); |
| }; |
| #endif |
| |
| |
| // Visitor class to verify interior pointers in spaces that do not contain |
| // or care about intergenerational references. All heap object pointers have to |
| // point into the heap to a location that has a map pointer at its first word. |
| // Caveat: Heap::Contains is an approximation because it can return true for |
| // objects in a heap space but above the allocation pointer. |
| class VerifyPointersVisitor: public ObjectVisitor { |
| public: |
| inline void VisitPointers(Object** start, Object** end); |
| }; |
| |
| |
| // Space iterator for iterating over all spaces of the heap. Returns each space |
| // in turn, and null when it is done. |
| class AllSpaces BASE_EMBEDDED { |
| public: |
| explicit AllSpaces(Heap* heap) : heap_(heap), counter_(FIRST_SPACE) {} |
| Space* next(); |
| private: |
| Heap* heap_; |
| int counter_; |
| }; |
| |
| |
| // Space iterator for iterating over all old spaces of the heap: Old pointer |
| // space, old data space and code space. Returns each space in turn, and null |
| // when it is done. |
| class OldSpaces BASE_EMBEDDED { |
| public: |
| explicit OldSpaces(Heap* heap) : heap_(heap), counter_(OLD_POINTER_SPACE) {} |
| OldSpace* next(); |
| private: |
| Heap* heap_; |
| int counter_; |
| }; |
| |
| |
| // Space iterator for iterating over all the paged spaces of the heap: Map |
| // space, old pointer space, old data space, code space and cell space. Returns |
| // each space in turn, and null when it is done. |
| class PagedSpaces BASE_EMBEDDED { |
| public: |
| explicit PagedSpaces(Heap* heap) : heap_(heap), counter_(OLD_POINTER_SPACE) {} |
| PagedSpace* next(); |
| private: |
| Heap* heap_; |
| int counter_; |
| }; |
| |
| |
| // Space iterator for iterating over all spaces of the heap. |
| // For each space an object iterator is provided. The deallocation of the |
| // returned object iterators is handled by the space iterator. |
| class SpaceIterator : public Malloced { |
| public: |
| explicit SpaceIterator(Heap* heap); |
| SpaceIterator(Heap* heap, HeapObjectCallback size_func); |
| virtual ~SpaceIterator(); |
| |
| bool has_next(); |
| ObjectIterator* next(); |
| |
| private: |
| ObjectIterator* CreateIterator(); |
| |
| Heap* heap_; |
| int current_space_; // from enum AllocationSpace. |
| ObjectIterator* iterator_; // object iterator for the current space. |
| HeapObjectCallback size_func_; |
| }; |
| |
| |
| // A HeapIterator provides iteration over the whole heap. It |
| // aggregates the specific iterators for the different spaces as |
| // these can only iterate over one space only. |
| // |
| // HeapIterator can skip free list nodes (that is, de-allocated heap |
| // objects that still remain in the heap). As implementation of free |
| // nodes filtering uses GC marks, it can't be used during MS/MC GC |
| // phases. Also, it is forbidden to interrupt iteration in this mode, |
| // as this will leave heap objects marked (and thus, unusable). |
| class HeapObjectsFilter; |
| |
| class HeapIterator BASE_EMBEDDED { |
| public: |
| enum HeapObjectsFiltering { |
| kNoFiltering, |
| kFilterUnreachable |
| }; |
| |
| explicit HeapIterator(Heap* heap); |
| HeapIterator(Heap* heap, HeapObjectsFiltering filtering); |
| ~HeapIterator(); |
| |
| HeapObject* next(); |
| void reset(); |
| |
| private: |
| // Perform the initialization. |
| void Init(); |
| // Perform all necessary shutdown (destruction) work. |
| void Shutdown(); |
| HeapObject* NextObject(); |
| |
| Heap* heap_; |
| HeapObjectsFiltering filtering_; |
| HeapObjectsFilter* filter_; |
| // Space iterator for iterating all the spaces. |
| SpaceIterator* space_iterator_; |
| // Object iterator for the space currently being iterated. |
| ObjectIterator* object_iterator_; |
| }; |
| |
| |
| // Cache for mapping (map, property name) into field offset. |
| // Cleared at startup and prior to mark sweep collection. |
| class KeyedLookupCache { |
| public: |
| // Lookup field offset for (map, name). If absent, -1 is returned. |
| int Lookup(Map* map, String* name); |
| |
| // Update an element in the cache. |
| void Update(Map* map, String* name, int field_offset); |
| |
| // Clear the cache. |
| void Clear(); |
| |
| static const int kLength = 256; |
| static const int kCapacityMask = kLength - 1; |
| static const int kMapHashShift = 5; |
| static const int kHashMask = -4; // Zero the last two bits. |
| static const int kEntriesPerBucket = 4; |
| static const int kNotFound = -1; |
| |
| // kEntriesPerBucket should be a power of 2. |
| STATIC_ASSERT((kEntriesPerBucket & (kEntriesPerBucket - 1)) == 0); |
| STATIC_ASSERT(kEntriesPerBucket == -kHashMask); |
| |
| private: |
| KeyedLookupCache() { |
| for (int i = 0; i < kLength; ++i) { |
| keys_[i].map = NULL; |
| keys_[i].name = NULL; |
| field_offsets_[i] = kNotFound; |
| } |
| } |
| |
| static inline int Hash(Map* map, String* name); |
| |
| // Get the address of the keys and field_offsets arrays. Used in |
| // generated code to perform cache lookups. |
| Address keys_address() { |
| return reinterpret_cast<Address>(&keys_); |
| } |
| |
| Address field_offsets_address() { |
| return reinterpret_cast<Address>(&field_offsets_); |
| } |
| |
| struct Key { |
| Map* map; |
| String* name; |
| }; |
| |
| Key keys_[kLength]; |
| int field_offsets_[kLength]; |
| |
| friend class ExternalReference; |
| friend class Isolate; |
| DISALLOW_COPY_AND_ASSIGN(KeyedLookupCache); |
| }; |
| |
| |
| // Cache for mapping (map, property name) into descriptor index. |
| // The cache contains both positive and negative results. |
| // Descriptor index equals kNotFound means the property is absent. |
| // Cleared at startup and prior to any gc. |
| class DescriptorLookupCache { |
| public: |
| // Lookup descriptor index for (map, name). |
| // If absent, kAbsent is returned. |
| int Lookup(Map* source, String* name) { |
| if (!StringShape(name).IsSymbol()) return kAbsent; |
| int index = Hash(source, name); |
| Key& key = keys_[index]; |
| if ((key.source == source) && (key.name == name)) return results_[index]; |
| return kAbsent; |
| } |
| |
| // Update an element in the cache. |
| void Update(Map* source, String* name, int result) { |
| ASSERT(result != kAbsent); |
| if (StringShape(name).IsSymbol()) { |
| int index = Hash(source, name); |
| Key& key = keys_[index]; |
| key.source = source; |
| key.name = name; |
| results_[index] = result; |
| } |
| } |
| |
| // Clear the cache. |
| void Clear(); |
| |
| static const int kAbsent = -2; |
| |
| private: |
| DescriptorLookupCache() { |
| for (int i = 0; i < kLength; ++i) { |
| keys_[i].source = NULL; |
| keys_[i].name = NULL; |
| results_[i] = kAbsent; |
| } |
| } |
| |
| static int Hash(Object* source, String* name) { |
| // Uses only lower 32 bits if pointers are larger. |
| uint32_t source_hash = |
| static_cast<uint32_t>(reinterpret_cast<uintptr_t>(source)) |
| >> kPointerSizeLog2; |
| uint32_t name_hash = |
| static_cast<uint32_t>(reinterpret_cast<uintptr_t>(name)) |
| >> kPointerSizeLog2; |
| return (source_hash ^ name_hash) % kLength; |
| } |
| |
| static const int kLength = 64; |
| struct Key { |
| Map* source; |
| String* name; |
| }; |
| |
| Key keys_[kLength]; |
| int results_[kLength]; |
| |
| friend class Isolate; |
| DISALLOW_COPY_AND_ASSIGN(DescriptorLookupCache); |
| }; |
| |
| |
| // A helper class to document/test C++ scopes where we do not |
| // expect a GC. Usage: |
| // |
| // /* Allocation not allowed: we cannot handle a GC in this scope. */ |
| // { AssertNoAllocation nogc; |
| // ... |
| // } |
| class AssertNoAllocation { |
| public: |
| inline AssertNoAllocation(); |
| inline ~AssertNoAllocation(); |
| |
| #ifdef DEBUG |
| private: |
| bool old_state_; |
| bool active_; |
| #endif |
| }; |
| |
| |
| class DisableAssertNoAllocation { |
| public: |
| inline DisableAssertNoAllocation(); |
| inline ~DisableAssertNoAllocation(); |
| |
| #ifdef DEBUG |
| private: |
| bool old_state_; |
| bool active_; |
| #endif |
| }; |
| |
| // GCTracer collects and prints ONE line after each garbage collector |
| // invocation IFF --trace_gc is used. |
| |
| class GCTracer BASE_EMBEDDED { |
| public: |
| class Scope BASE_EMBEDDED { |
| public: |
| enum ScopeId { |
| EXTERNAL, |
| MC_MARK, |
| MC_SWEEP, |
| MC_SWEEP_NEWSPACE, |
| MC_EVACUATE_PAGES, |
| MC_UPDATE_NEW_TO_NEW_POINTERS, |
| MC_UPDATE_ROOT_TO_NEW_POINTERS, |
| MC_UPDATE_OLD_TO_NEW_POINTERS, |
| MC_UPDATE_POINTERS_TO_EVACUATED, |
| MC_UPDATE_POINTERS_BETWEEN_EVACUATED, |
| MC_UPDATE_MISC_POINTERS, |
| MC_FLUSH_CODE, |
| kNumberOfScopes |
| }; |
| |
| Scope(GCTracer* tracer, ScopeId scope) |
| : tracer_(tracer), |
| scope_(scope) { |
| start_time_ = OS::TimeCurrentMillis(); |
| } |
| |
| ~Scope() { |
| ASSERT(scope_ < kNumberOfScopes); // scope_ is unsigned. |
| tracer_->scopes_[scope_] += OS::TimeCurrentMillis() - start_time_; |
| } |
| |
| private: |
| GCTracer* tracer_; |
| ScopeId scope_; |
| double start_time_; |
| }; |
| |
| explicit GCTracer(Heap* heap, |
| const char* gc_reason, |
| const char* collector_reason); |
| ~GCTracer(); |
| |
| // Sets the collector. |
| void set_collector(GarbageCollector collector) { collector_ = collector; } |
| |
| // Sets the GC count. |
| void set_gc_count(unsigned int count) { gc_count_ = count; } |
| |
| // Sets the full GC count. |
| void set_full_gc_count(int count) { full_gc_count_ = count; } |
| |
| void increment_promoted_objects_size(int object_size) { |
| promoted_objects_size_ += object_size; |
| } |
| |
| void increment_nodes_died_in_new_space() { |
| nodes_died_in_new_space_++; |
| } |
| |
| void increment_nodes_copied_in_new_space() { |
| nodes_copied_in_new_space_++; |
| } |
| |
| void increment_nodes_promoted() { |
| nodes_promoted_++; |
| } |
| |
| private: |
| // Returns a string matching the collector. |
| const char* CollectorString(); |
| |
| // Returns size of object in heap (in MB). |
| inline double SizeOfHeapObjects(); |
| |
| // Timestamp set in the constructor. |
| double start_time_; |
| |
| // Size of objects in heap set in constructor. |
| intptr_t start_object_size_; |
| |
| // Size of memory allocated from OS set in constructor. |
| intptr_t start_memory_size_; |
| |
| // Type of collector. |
| GarbageCollector collector_; |
| |
| // A count (including this one, e.g. the first collection is 1) of the |
| // number of garbage collections. |
| unsigned int gc_count_; |
| |
| // A count (including this one) of the number of full garbage collections. |
| int full_gc_count_; |
| |
| // Amounts of time spent in different scopes during GC. |
| double scopes_[Scope::kNumberOfScopes]; |
| |
| // Total amount of space either wasted or contained in one of free lists |
| // before the current GC. |
| intptr_t in_free_list_or_wasted_before_gc_; |
| |
| // Difference between space used in the heap at the beginning of the current |
| // collection and the end of the previous collection. |
| intptr_t allocated_since_last_gc_; |
| |
| // Amount of time spent in mutator that is time elapsed between end of the |
| // previous collection and the beginning of the current one. |
| double spent_in_mutator_; |
| |
| // Size of objects promoted during the current collection. |
| intptr_t promoted_objects_size_; |
| |
| // Number of died nodes in the new space. |
| int nodes_died_in_new_space_; |
| |
| // Number of copied nodes to the new space. |
| int nodes_copied_in_new_space_; |
| |
| // Number of promoted nodes to the old space. |
| int nodes_promoted_; |
| |
| // Incremental marking steps counters. |
| int steps_count_; |
| double steps_took_; |
| double longest_step_; |
| int steps_count_since_last_gc_; |
| double steps_took_since_last_gc_; |
| |
| Heap* heap_; |
| |
| const char* gc_reason_; |
| const char* collector_reason_; |
| }; |
| |
| |
| class RegExpResultsCache { |
| public: |
| enum ResultsCacheType { REGEXP_MULTIPLE_INDICES, STRING_SPLIT_SUBSTRINGS }; |
| |
| // Attempt to retrieve a cached result. On failure, 0 is returned as a Smi. |
| // On success, the returned result is guaranteed to be a COW-array. |
| static Object* Lookup(Heap* heap, |
| String* key_string, |
| Object* key_pattern, |
| ResultsCacheType type); |
| // Attempt to add value_array to the cache specified by type. On success, |
| // value_array is turned into a COW-array. |
| static void Enter(Heap* heap, |
| String* key_string, |
| Object* key_pattern, |
| FixedArray* value_array, |
| ResultsCacheType type); |
| static void Clear(FixedArray* cache); |
| static const int kRegExpResultsCacheSize = 0x100; |
| |
| private: |
| static const int kArrayEntriesPerCacheEntry = 4; |
| static const int kStringOffset = 0; |
| static const int kPatternOffset = 1; |
| static const int kArrayOffset = 2; |
| }; |
| |
| |
| class TranscendentalCache { |
| public: |
| enum Type {ACOS, ASIN, ATAN, COS, EXP, LOG, SIN, TAN, kNumberOfCaches}; |
| static const int kTranscendentalTypeBits = 3; |
| STATIC_ASSERT((1 << kTranscendentalTypeBits) >= kNumberOfCaches); |
| |
| // Returns a heap number with f(input), where f is a math function specified |
| // by the 'type' argument. |
| MUST_USE_RESULT inline MaybeObject* Get(Type type, double input); |
| |
| // The cache contains raw Object pointers. This method disposes of |
| // them before a garbage collection. |
| void Clear(); |
| |
| private: |
| class SubCache { |
| static const int kCacheSize = 512; |
| |
| explicit SubCache(Type t); |
| |
| MUST_USE_RESULT inline MaybeObject* Get(double input); |
| |
| inline double Calculate(double input); |
| |
| struct Element { |
| uint32_t in[2]; |
| Object* output; |
| }; |
| |
| union Converter { |
| double dbl; |
| uint32_t integers[2]; |
| }; |
| |
| inline static int Hash(const Converter& c) { |
| uint32_t hash = (c.integers[0] ^ c.integers[1]); |
| hash ^= static_cast<int32_t>(hash) >> 16; |
| hash ^= static_cast<int32_t>(hash) >> 8; |
| return (hash & (kCacheSize - 1)); |
| } |
| |
| Element elements_[kCacheSize]; |
| Type type_; |
| Isolate* isolate_; |
| |
| // Allow access to the caches_ array as an ExternalReference. |
| friend class ExternalReference; |
| // Inline implementation of the cache. |
| friend class TranscendentalCacheStub; |
| // For evaluating value. |
| friend class TranscendentalCache; |
| |
| DISALLOW_COPY_AND_ASSIGN(SubCache); |
| }; |
| |
| TranscendentalCache() { |
| for (int i = 0; i < kNumberOfCaches; ++i) caches_[i] = NULL; |
| } |
| |
| // Used to create an external reference. |
| inline Address cache_array_address(); |
| |
| // Instantiation |
| friend class Isolate; |
| // Inline implementation of the caching. |
| friend class TranscendentalCacheStub; |
| // Allow access to the caches_ array as an ExternalReference. |
| friend class ExternalReference; |
| |
| SubCache* caches_[kNumberOfCaches]; |
| DISALLOW_COPY_AND_ASSIGN(TranscendentalCache); |
| }; |
| |
| |
| // Abstract base class for checking whether a weak object should be retained. |
| class WeakObjectRetainer { |
| public: |
| virtual ~WeakObjectRetainer() {} |
| |
| // Return whether this object should be retained. If NULL is returned the |
| // object has no references. Otherwise the address of the retained object |
| // should be returned as in some GC situations the object has been moved. |
| virtual Object* RetainAs(Object* object) = 0; |
| }; |
| |
| |
| // Intrusive object marking uses least significant bit of |
| // heap object's map word to mark objects. |
| // Normally all map words have least significant bit set |
| // because they contain tagged map pointer. |
| // If the bit is not set object is marked. |
| // All objects should be unmarked before resuming |
| // JavaScript execution. |
| class IntrusiveMarking { |
| public: |
| static bool IsMarked(HeapObject* object) { |
| return (object->map_word().ToRawValue() & kNotMarkedBit) == 0; |
| } |
| |
| static void ClearMark(HeapObject* object) { |
| uintptr_t map_word = object->map_word().ToRawValue(); |
| object->set_map_word(MapWord::FromRawValue(map_word | kNotMarkedBit)); |
| ASSERT(!IsMarked(object)); |
| } |
| |
| static void SetMark(HeapObject* object) { |
| uintptr_t map_word = object->map_word().ToRawValue(); |
| object->set_map_word(MapWord::FromRawValue(map_word & ~kNotMarkedBit)); |
| ASSERT(IsMarked(object)); |
| } |
| |
| static Map* MapOfMarkedObject(HeapObject* object) { |
| uintptr_t map_word = object->map_word().ToRawValue(); |
| return MapWord::FromRawValue(map_word | kNotMarkedBit).ToMap(); |
| } |
| |
| static int SizeOfMarkedObject(HeapObject* object) { |
| return object->SizeFromMap(MapOfMarkedObject(object)); |
| } |
| |
| private: |
| static const uintptr_t kNotMarkedBit = 0x1; |
| STATIC_ASSERT((kHeapObjectTag & kNotMarkedBit) != 0); |
| }; |
| |
| |
| #ifdef DEBUG |
| // Helper class for tracing paths to a search target Object from all roots. |
| // The TracePathFrom() method can be used to trace paths from a specific |
| // object to the search target object. |
| class PathTracer : public ObjectVisitor { |
| public: |
| enum WhatToFind { |
| FIND_ALL, // Will find all matches. |
| FIND_FIRST // Will stop the search after first match. |
| }; |
| |
| // For the WhatToFind arg, if FIND_FIRST is specified, tracing will stop |
| // after the first match. If FIND_ALL is specified, then tracing will be |
| // done for all matches. |
| PathTracer(Object* search_target, |
| WhatToFind what_to_find, |
| VisitMode visit_mode) |
| : search_target_(search_target), |
| found_target_(false), |
| found_target_in_trace_(false), |
| what_to_find_(what_to_find), |
| visit_mode_(visit_mode), |
| object_stack_(20), |
| no_alloc() {} |
| |
| virtual void VisitPointers(Object** start, Object** end); |
| |
| void Reset(); |
| void TracePathFrom(Object** root); |
| |
| bool found() const { return found_target_; } |
| |
| static Object* const kAnyGlobalObject; |
| |
| protected: |
| class MarkVisitor; |
| class UnmarkVisitor; |
| |
| void MarkRecursively(Object** p, MarkVisitor* mark_visitor); |
| void UnmarkRecursively(Object** p, UnmarkVisitor* unmark_visitor); |
| virtual void ProcessResults(); |
| |
| // Tags 0, 1, and 3 are used. Use 2 for marking visited HeapObject. |
| static const int kMarkTag = 2; |
| |
| Object* search_target_; |
| bool found_target_; |
| bool found_target_in_trace_; |
| WhatToFind what_to_find_; |
| VisitMode visit_mode_; |
| List<Object*> object_stack_; |
| |
| AssertNoAllocation no_alloc; // i.e. no gc allowed. |
| |
| private: |
| DISALLOW_IMPLICIT_CONSTRUCTORS(PathTracer); |
| }; |
| #endif // DEBUG |
| |
| } } // namespace v8::internal |
| |
| #endif // V8_HEAP_H_ |