mirrored from https://chromium.googlesource.com/v8/v8.git
/
heap.h
3135 lines (2556 loc) · 118 KB
/
heap.h
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// 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 <cmath>
#include "allocation.h"
#include "assert-scope.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(Oddball, uninitialized_value, UninitializedValue) \
V(Map, cell_map, CellMap) \
V(Map, global_property_cell_map, GlobalPropertyCellMap) \
V(Map, shared_function_info_map, SharedFunctionInfoMap) \
V(Map, meta_map, MetaMap) \
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(Map, constant_pool_array_map, ConstantPoolArrayMap) \
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(DescriptorArray, empty_descriptor_array, EmptyDescriptorArray) \
V(ConstantPoolArray, empty_constant_pool_array, EmptyConstantPoolArray) \
V(Oddball, arguments_marker, ArgumentsMarker) \
/* The 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, symbol_map, SymbolMap) \
V(Map, string_map, StringMap) \
V(Map, ascii_string_map, AsciiStringMap) \
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, external_string_map, ExternalStringMap) \
V(Map, \
external_string_with_one_byte_data_map, \
ExternalStringWithOneByteDataMap) \
V(Map, external_ascii_string_map, ExternalAsciiStringMap) \
V(Map, short_external_string_map, ShortExternalStringMap) \
V(Map, \
short_external_string_with_one_byte_data_map, \
ShortExternalStringWithOneByteDataMap) \
V(Map, internalized_string_map, InternalizedStringMap) \
V(Map, ascii_internalized_string_map, AsciiInternalizedStringMap) \
V(Map, cons_internalized_string_map, ConsInternalizedStringMap) \
V(Map, cons_ascii_internalized_string_map, ConsAsciiInternalizedStringMap) \
V(Map, \
external_internalized_string_map, \
ExternalInternalizedStringMap) \
V(Map, \
external_internalized_string_with_one_byte_data_map, \
ExternalInternalizedStringWithOneByteDataMap) \
V(Map, \
external_ascii_internalized_string_map, \
ExternalAsciiInternalizedStringMap) \
V(Map, \
short_external_internalized_string_map, \
ShortExternalInternalizedStringMap) \
V(Map, \
short_external_internalized_string_with_one_byte_data_map, \
ShortExternalInternalizedStringWithOneByteDataMap) \
V(Map, \
short_external_ascii_internalized_string_map, \
ShortExternalAsciiInternalizedStringMap) \
V(Map, short_external_ascii_string_map, ShortExternalAsciiStringMap) \
V(Map, undetectable_string_map, UndetectableStringMap) \
V(Map, undetectable_ascii_string_map, UndetectableAsciiStringMap) \
V(Map, external_int8_array_map, ExternalInt8ArrayMap) \
V(Map, external_uint8_array_map, ExternalUint8ArrayMap) \
V(Map, external_int16_array_map, ExternalInt16ArrayMap) \
V(Map, external_uint16_array_map, ExternalUint16ArrayMap) \
V(Map, external_int32_array_map, ExternalInt32ArrayMap) \
V(Map, external_uint32_array_map, ExternalUint32ArrayMap) \
V(Map, external_float32_array_map, ExternalFloat32ArrayMap) \
V(Map, external_float64_array_map, ExternalFloat64ArrayMap) \
V(Map, external_uint8_clamped_array_map, ExternalUint8ClampedArrayMap) \
V(ExternalArray, empty_external_int8_array, \
EmptyExternalInt8Array) \
V(ExternalArray, empty_external_uint8_array, \
EmptyExternalUint8Array) \
V(ExternalArray, empty_external_int16_array, EmptyExternalInt16Array) \
V(ExternalArray, empty_external_uint16_array, \
EmptyExternalUint16Array) \
V(ExternalArray, empty_external_int32_array, EmptyExternalInt32Array) \
V(ExternalArray, empty_external_uint32_array, \
EmptyExternalUint32Array) \
V(ExternalArray, empty_external_float32_array, EmptyExternalFloat32Array) \
V(ExternalArray, empty_external_float64_array, EmptyExternalFloat64Array) \
V(ExternalArray, empty_external_uint8_clamped_array, \
EmptyExternalUint8ClampedArray) \
V(Map, fixed_uint8_array_map, FixedUint8ArrayMap) \
V(Map, fixed_int8_array_map, FixedInt8ArrayMap) \
V(Map, fixed_uint16_array_map, FixedUint16ArrayMap) \
V(Map, fixed_int16_array_map, FixedInt16ArrayMap) \
V(Map, fixed_uint32_array_map, FixedUint32ArrayMap) \
V(Map, fixed_int32_array_map, FixedInt32ArrayMap) \
V(Map, fixed_float32_array_map, FixedFloat32ArrayMap) \
V(Map, fixed_float64_array_map, FixedFloat64ArrayMap) \
V(Map, fixed_uint8_clamped_array_map, FixedUint8ClampedArrayMap) \
V(Map, sloppy_arguments_elements_map, SloppyArgumentsElementsMap) \
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(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(Script, empty_script, EmptyScript) \
V(NameDictionary, intrinsic_function_names, IntrinsicFunctionNames) \
V(Cell, undefined_cell, UndefineCell) \
V(JSObject, observation_state, ObservationState) \
V(Map, external_map, ExternalMap) \
V(Object, symbol_registry, SymbolRegistry) \
V(Symbol, frozen_symbol, FrozenSymbol) \
V(Symbol, nonexistent_symbol, NonExistentSymbol) \
V(Symbol, elements_transition_symbol, ElementsTransitionSymbol) \
V(SeededNumberDictionary, empty_slow_element_dictionary, \
EmptySlowElementDictionary) \
V(Symbol, observed_symbol, ObservedSymbol) \
V(Symbol, uninitialized_symbol, UninitializedSymbol) \
V(Symbol, megamorphic_symbol, MegamorphicSymbol) \
V(FixedArray, materialized_objects, MaterializedObjects) \
V(FixedArray, allocation_sites_scratchpad, AllocationSitesScratchpad) \
V(JSObject, microtask_state, MicrotaskState)
// Entries in this list are limited to Smis and are not visited during GC.
#define SMI_ROOT_LIST(V) \
V(Smi, stack_limit, StackLimit) \
V(Smi, real_stack_limit, RealStackLimit) \
V(Smi, last_script_id, LastScriptId) \
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)
#define ROOT_LIST(V) \
STRONG_ROOT_LIST(V) \
SMI_ROOT_LIST(V) \
V(StringTable, string_table, StringTable)
// Heap roots that are known to be immortal immovable, for which we can safely
// skip write barriers.
#define IMMORTAL_IMMOVABLE_ROOT_LIST(V) \
V(byte_array_map) \
V(free_space_map) \
V(one_pointer_filler_map) \
V(two_pointer_filler_map) \
V(undefined_value) \
V(the_hole_value) \
V(null_value) \
V(true_value) \
V(false_value) \
V(uninitialized_value) \
V(cell_map) \
V(global_property_cell_map) \
V(shared_function_info_map) \
V(meta_map) \
V(heap_number_map) \
V(native_context_map) \
V(fixed_array_map) \
V(code_map) \
V(scope_info_map) \
V(fixed_cow_array_map) \
V(fixed_double_array_map) \
V(constant_pool_array_map) \
V(no_interceptor_result_sentinel) \
V(hash_table_map) \
V(empty_fixed_array) \
V(empty_byte_array) \
V(empty_descriptor_array) \
V(empty_constant_pool_array) \
V(arguments_marker) \
V(symbol_map) \
V(sloppy_arguments_elements_map) \
V(function_context_map) \
V(catch_context_map) \
V(with_context_map) \
V(block_context_map) \
V(module_context_map) \
V(global_context_map) \
V(oddball_map) \
V(message_object_map) \
V(foreign_map) \
V(neander_map)
#define INTERNALIZED_STRING_LIST(V) \
V(Array_string, "Array") \
V(Object_string, "Object") \
V(proto_string, "__proto__") \
V(arguments_string, "arguments") \
V(Arguments_string, "Arguments") \
V(call_string, "call") \
V(apply_string, "apply") \
V(caller_string, "caller") \
V(boolean_string, "boolean") \
V(Boolean_string, "Boolean") \
V(callee_string, "callee") \
V(constructor_string, "constructor") \
V(dot_result_string, ".result") \
V(dot_for_string, ".for.") \
V(dot_iterator_string, ".iterator") \
V(dot_generator_object_string, ".generator_object") \
V(eval_string, "eval") \
V(empty_string, "") \
V(function_string, "function") \
V(length_string, "length") \
V(module_string, "module") \
V(name_string, "name") \
V(native_string, "native") \
V(null_string, "null") \
V(number_string, "number") \
V(Number_string, "Number") \
V(nan_string, "NaN") \
V(RegExp_string, "RegExp") \
V(source_string, "source") \
V(global_string, "global") \
V(ignore_case_string, "ignoreCase") \
V(multiline_string, "multiline") \
V(input_string, "input") \
V(index_string, "index") \
V(last_index_string, "lastIndex") \
V(object_string, "object") \
V(literals_string, "literals") \
V(prototype_string, "prototype") \
V(string_string, "string") \
V(String_string, "String") \
V(symbol_string, "symbol") \
V(Symbol_string, "Symbol") \
V(for_string, "for") \
V(for_api_string, "for_api") \
V(for_intern_string, "for_intern") \
V(private_api_string, "private_api") \
V(private_intern_string, "private_intern") \
V(Date_string, "Date") \
V(this_string, "this") \
V(to_string_string, "toString") \
V(char_at_string, "CharAt") \
V(undefined_string, "undefined") \
V(value_of_string, "valueOf") \
V(stack_string, "stack") \
V(toJSON_string, "toJSON") \
V(InitializeVarGlobal_string, "InitializeVarGlobal") \
V(InitializeConstGlobal_string, "InitializeConstGlobal") \
V(KeyedLoadElementMonomorphic_string, \
"KeyedLoadElementMonomorphic") \
V(KeyedStoreElementMonomorphic_string, \
"KeyedStoreElementMonomorphic") \
V(stack_overflow_string, "kStackOverflowBoilerplate") \
V(illegal_access_string, "illegal access") \
V(illegal_execution_state_string, "illegal execution state") \
V(get_string, "get") \
V(set_string, "set") \
V(map_field_string, "%map") \
V(elements_field_string, "%elements") \
V(length_field_string, "%length") \
V(cell_value_string, "%cell_value") \
V(function_class_string, "Function") \
V(illegal_argument_string, "illegal argument") \
V(MakeReferenceError_string, "MakeReferenceError") \
V(MakeSyntaxError_string, "MakeSyntaxError") \
V(MakeTypeError_string, "MakeTypeError") \
V(illegal_return_string, "illegal_return") \
V(illegal_break_string, "illegal_break") \
V(illegal_continue_string, "illegal_continue") \
V(unknown_label_string, "unknown_label") \
V(redeclaration_string, "redeclaration") \
V(space_string, " ") \
V(exec_string, "exec") \
V(zero_string, "0") \
V(global_eval_string, "GlobalEval") \
V(identity_hash_string, "v8::IdentityHash") \
V(closure_string, "(closure)") \
V(use_strict_string, "use strict") \
V(dot_string, ".") \
V(anonymous_function_string, "(anonymous function)") \
V(compare_ic_string, "==") \
V(strict_compare_ic_string, "===") \
V(infinity_string, "Infinity") \
V(minus_infinity_string, "-Infinity") \
V(hidden_stack_trace_string, "v8::hidden_stack_trace") \
V(query_colon_string, "(?:)") \
V(Generator_string, "Generator") \
V(throw_string, "throw") \
V(done_string, "done") \
V(value_string, "value") \
V(next_string, "next") \
V(byte_length_string, "byteLength") \
V(byte_offset_string, "byteOffset") \
V(buffer_string, "buffer")
// 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:
explicit ExternalStringTable(Heap* heap) : heap_(heap) { }
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);
};
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();
// Prepares the heap, setting up memory areas that are needed in the isolate
// without actually creating any objects.
bool SetUp();
// Bootstraps the object heap with the core set of objects required to run.
// Returns whether it succeeded.
bool CreateHeapObjects();
// 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 maximum amount of memory ever committed for the heap.
intptr_t MaximumCommittedMemory() { return maximum_committed_; }
// Updates the maximum committed memory for the heap. Should be called
// whenever a space grows.
void UpdateMaximumCommitted();
// 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_; }
PropertyCellSpace* property_cell_space() {
return property_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 PROPERTY_CELL_SPACE:
return property_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();
}
Address* OldPointerSpaceAllocationTopAddress() {
return old_pointer_space_->allocation_top_address();
}
Address* OldPointerSpaceAllocationLimitAddress() {
return old_pointer_space_->allocation_limit_address();
}
Address* OldDataSpaceAllocationTopAddress() {
return old_data_space_->allocation_top_address();
}
Address* OldDataSpaceAllocationLimitAddress() {
return old_data_space_->allocation_limit_address();
}
// Allocates and initializes a new JavaScript object based on a
// constructor.
// Returns Failure::RetryAfterGC(requested_bytes, space) if the allocation
// failed.
// If allocation_site is non-null, then a memento is emitted after the object
// that points to the site.
// Please note this does not perform a garbage collection.
MUST_USE_RESULT MaybeObject* AllocateJSObject(
JSFunction* constructor,
PretenureFlag pretenure = NOT_TENURED,
AllocationSite* allocation_site = NULL);
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);
MUST_USE_RESULT MaybeObject* AllocateJSArrayStorage(
JSArray* array,
int length,
int capacity,
ArrayStorageAllocationMode mode = DONT_INITIALIZE_ARRAY_ELEMENTS);
// Allocate a JSArray with no elements
MUST_USE_RESULT MaybeObject* AllocateJSArrayWithElements(
FixedArrayBase* array_base,
ElementsKind elements_kind,
int length,
PretenureFlag pretenure = NOT_TENURED);
// Returns a deep copy of the JavaScript object.
// Properties and elements are copied too.
// Returns failure if allocation failed.
// Optionally takes an AllocationSite to be appended in an AllocationMemento.
MUST_USE_RESULT MaybeObject* CopyJSObject(JSObject* source,
AllocationSite* site = NULL);
// Allocates a JS ArrayBuffer object.
// Returns Failure::RetryAfterGC(requested_bytes, space) if the allocation
// failed.
// Please note this does not perform a garbage collection.
MUST_USE_RESULT MaybeObject* AllocateJSArrayBuffer();
// 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.
// Passing an allocation site means that a memento will be created that
// points to the site.
// Please note this does not perform a garbage collection.
MUST_USE_RESULT MaybeObject* AllocateJSObjectFromMap(
Map* map,
PretenureFlag pretenure = NOT_TENURED,
bool alloc_props = true,
AllocationSite* allocation_site = NULL);
// 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,
AllocationSite* allocation_site = NULL);
// 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);
// 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();
// Iterates the whole code space to clear all ICs of the given kind.
void ClearAllICsByKind(Code::Kind kind);
// 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 an internalized string 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* AllocateInternalizedStringFromUtf8(
Vector<const char> str,
int chars,
uint32_t hash_field);
MUST_USE_RESULT inline MaybeObject* AllocateOneByteInternalizedString(
Vector<const uint8_t> str,
uint32_t hash_field);
MUST_USE_RESULT inline MaybeObject* AllocateTwoByteInternalizedString(
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* AllocateInternalizedStringImpl(
T t, int chars, uint32_t hash_field);
template<bool is_one_byte, typename T>
MUST_USE_RESULT MaybeObject* AllocateInternalizedStringImpl(
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 = NOT_TENURED);
// 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);
// Allocates a fixed typed 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* AllocateFixedTypedArray(
int length,
ExternalArrayType array_type,
PretenureFlag pretenure);
// Allocate a symbol in old space.
// Returns Failure::RetryAfterGC(requested_bytes, space) if the allocation
// failed.
// Please note this does not perform a garbage collection.
MUST_USE_RESULT MaybeObject* AllocateSymbol();
MUST_USE_RESULT MaybeObject* AllocatePrivateSymbol();
// Allocate a tenured AllocationSite. It's payload is null
MUST_USE_RESULT MaybeObject* AllocateAllocationSite();
// 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 = NOT_TENURED);
// 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 and return it. Returns
// Failure::RetryAfterGC(requested_bytes, space) if the allocation failed.
MUST_USE_RESULT MaybeObject* CopyAndTenureFixedCOWArray(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);