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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_INL_H_
#define V8_HEAP_INL_H_
#include "heap.h"
#include "isolate.h"
#include "list-inl.h"
#include "objects.h"
#include "platform.h"
#include "v8-counters.h"
#include "store-buffer.h"
#include "store-buffer-inl.h"
namespace v8 {
namespace internal {
void PromotionQueue::insert(HeapObject* target, int size) {
if (emergency_stack_ != NULL) {
emergency_stack_->Add(Entry(target, size));
return;
}
if (NewSpacePage::IsAtStart(reinterpret_cast<Address>(rear_))) {
NewSpacePage* rear_page =
NewSpacePage::FromAddress(reinterpret_cast<Address>(rear_));
ASSERT(!rear_page->prev_page()->is_anchor());
rear_ = reinterpret_cast<intptr_t*>(rear_page->prev_page()->area_end());
ActivateGuardIfOnTheSamePage();
}
if (guard_) {
ASSERT(GetHeadPage() ==
Page::FromAllocationTop(reinterpret_cast<Address>(limit_)));
if ((rear_ - 2) < limit_) {
RelocateQueueHead();
emergency_stack_->Add(Entry(target, size));
return;
}
}
*(--rear_) = reinterpret_cast<intptr_t>(target);
*(--rear_) = size;
// Assert no overflow into live objects.
#ifdef DEBUG
SemiSpace::AssertValidRange(target->GetIsolate()->heap()->new_space()->top(),
reinterpret_cast<Address>(rear_));
#endif
}
void PromotionQueue::ActivateGuardIfOnTheSamePage() {
guard_ = guard_ ||
heap_->new_space()->active_space()->current_page()->address() ==
GetHeadPage()->address();
}
MaybeObject* Heap::AllocateStringFromUtf8(Vector<const char> str,
PretenureFlag pretenure) {
// Check for ASCII first since this is the common case.
const char* start = str.start();
int length = str.length();
int non_ascii_start = String::NonAsciiStart(start, length);
if (non_ascii_start >= length) {
// If the string is ASCII, we do not need to convert the characters
// since UTF8 is backwards compatible with ASCII.
return AllocateStringFromOneByte(str, pretenure);
}
// Non-ASCII and we need to decode.
return AllocateStringFromUtf8Slow(str, non_ascii_start, pretenure);
}
template<>
bool inline Heap::IsOneByte(Vector<const char> str, int chars) {
// TODO(dcarney): incorporate Latin-1 check when Latin-1 is supported?
// ASCII only check.
return chars == str.length();
}
template<>
bool inline Heap::IsOneByte(String* str, int chars) {
return str->IsOneByteRepresentation();
}
MaybeObject* Heap::AllocateInternalizedStringFromUtf8(
Vector<const char> str, int chars, uint32_t hash_field) {
if (IsOneByte(str, chars)) {
return AllocateOneByteInternalizedString(
Vector<const uint8_t>::cast(str), hash_field);
}
return AllocateInternalizedStringImpl<false>(str, chars, hash_field);
}
template<typename T>
MaybeObject* Heap::AllocateInternalizedStringImpl(
T t, int chars, uint32_t hash_field) {
if (IsOneByte(t, chars)) {
return AllocateInternalizedStringImpl<true>(t, chars, hash_field);
}
return AllocateInternalizedStringImpl<false>(t, chars, hash_field);
}
MaybeObject* Heap::AllocateOneByteInternalizedString(Vector<const uint8_t> str,
uint32_t hash_field) {
if (str.length() > SeqOneByteString::kMaxLength) {
return Failure::OutOfMemoryException(0x2);
}
// Compute map and object size.
Map* map = ascii_internalized_string_map();
int size = SeqOneByteString::SizeFor(str.length());
AllocationSpace space = SelectSpace(size, OLD_DATA_SPACE, TENURED);
// Allocate string.
Object* result;
{ MaybeObject* maybe_result = AllocateRaw(size, space, OLD_DATA_SPACE);
if (!maybe_result->ToObject(&result)) return maybe_result;
}
// String maps are all immortal immovable objects.
reinterpret_cast<HeapObject*>(result)->set_map_no_write_barrier(map);
// Set length and hash fields of the allocated string.
String* answer = String::cast(result);
answer->set_length(str.length());
answer->set_hash_field(hash_field);
ASSERT_EQ(size, answer->Size());
// Fill in the characters.
OS::MemCopy(answer->address() + SeqOneByteString::kHeaderSize,
str.start(), str.length());
return answer;
}
MaybeObject* Heap::AllocateTwoByteInternalizedString(Vector<const uc16> str,
uint32_t hash_field) {
if (str.length() > SeqTwoByteString::kMaxLength) {
return Failure::OutOfMemoryException(0x3);
}
// Compute map and object size.
Map* map = internalized_string_map();
int size = SeqTwoByteString::SizeFor(str.length());
AllocationSpace space = SelectSpace(size, OLD_DATA_SPACE, TENURED);
// Allocate string.
Object* result;
{ MaybeObject* maybe_result = AllocateRaw(size, space, OLD_DATA_SPACE);
if (!maybe_result->ToObject(&result)) return maybe_result;
}
reinterpret_cast<HeapObject*>(result)->set_map(map);
// Set length and hash fields of the allocated string.
String* answer = String::cast(result);
answer->set_length(str.length());
answer->set_hash_field(hash_field);
ASSERT_EQ(size, answer->Size());
// Fill in the characters.
OS::MemCopy(answer->address() + SeqTwoByteString::kHeaderSize,
str.start(), str.length() * kUC16Size);
return answer;
}
MaybeObject* Heap::CopyFixedArray(FixedArray* src) {
return CopyFixedArrayWithMap(src, src->map());
}
MaybeObject* Heap::CopyFixedDoubleArray(FixedDoubleArray* src) {
return CopyFixedDoubleArrayWithMap(src, src->map());
}
MaybeObject* Heap::CopyConstantPoolArray(ConstantPoolArray* src) {
return CopyConstantPoolArrayWithMap(src, src->map());
}
MaybeObject* Heap::AllocateRaw(int size_in_bytes,
AllocationSpace space,
AllocationSpace retry_space) {
ASSERT(AllowHandleAllocation::IsAllowed());
ASSERT(AllowHeapAllocation::IsAllowed());
ASSERT(gc_state_ == NOT_IN_GC);
HeapProfiler* profiler = isolate_->heap_profiler();
#ifdef DEBUG
if (FLAG_gc_interval >= 0 &&
!disallow_allocation_failure_ &&
Heap::allocation_timeout_-- <= 0) {
return Failure::RetryAfterGC(space);
}
isolate_->counters()->objs_since_last_full()->Increment();
isolate_->counters()->objs_since_last_young()->Increment();
#endif
HeapObject* object;
MaybeObject* result;
if (NEW_SPACE == space) {
result = new_space_.AllocateRaw(size_in_bytes);
if (always_allocate() && result->IsFailure() && retry_space != NEW_SPACE) {
space = retry_space;
} else {
if (profiler->is_tracking_allocations() && result->To(&object)) {
profiler->NewObjectEvent(object->address(), size_in_bytes);
}
return result;
}
}
if (OLD_POINTER_SPACE == space) {
result = old_pointer_space_->AllocateRaw(size_in_bytes);
} else if (OLD_DATA_SPACE == space) {
result = old_data_space_->AllocateRaw(size_in_bytes);
} else if (CODE_SPACE == space) {
result = code_space_->AllocateRaw(size_in_bytes);
} else if (LO_SPACE == space) {
result = lo_space_->AllocateRaw(size_in_bytes, NOT_EXECUTABLE);
} else if (CELL_SPACE == space) {
result = cell_space_->AllocateRaw(size_in_bytes);
} else if (PROPERTY_CELL_SPACE == space) {
result = property_cell_space_->AllocateRaw(size_in_bytes);
} else {
ASSERT(MAP_SPACE == space);
result = map_space_->AllocateRaw(size_in_bytes);
}
if (result->IsFailure()) old_gen_exhausted_ = true;
if (profiler->is_tracking_allocations() && result->To(&object)) {
profiler->NewObjectEvent(object->address(), size_in_bytes);
}
return result;
}
MaybeObject* Heap::NumberFromInt32(
int32_t value, PretenureFlag pretenure) {
if (Smi::IsValid(value)) return Smi::FromInt(value);
// Bypass NumberFromDouble to avoid various redundant checks.
return AllocateHeapNumber(FastI2D(value), pretenure);
}
MaybeObject* Heap::NumberFromUint32(
uint32_t value, PretenureFlag pretenure) {
if (static_cast<int32_t>(value) >= 0 &&
Smi::IsValid(static_cast<int32_t>(value))) {
return Smi::FromInt(static_cast<int32_t>(value));
}
// Bypass NumberFromDouble to avoid various redundant checks.
return AllocateHeapNumber(FastUI2D(value), pretenure);
}
void Heap::FinalizeExternalString(String* string) {
ASSERT(string->IsExternalString());
v8::String::ExternalStringResourceBase** resource_addr =
reinterpret_cast<v8::String::ExternalStringResourceBase**>(
reinterpret_cast<byte*>(string) +
ExternalString::kResourceOffset -
kHeapObjectTag);
// Dispose of the C++ object if it has not already been disposed.
if (*resource_addr != NULL) {
(*resource_addr)->Dispose();
*resource_addr = NULL;
}
}
bool Heap::InNewSpace(Object* object) {
bool result = new_space_.Contains(object);
ASSERT(!result || // Either not in new space
gc_state_ != NOT_IN_GC || // ... or in the middle of GC
InToSpace(object)); // ... or in to-space (where we allocate).
return result;
}
bool Heap::InNewSpace(Address address) {
return new_space_.Contains(address);
}
bool Heap::InFromSpace(Object* object) {
return new_space_.FromSpaceContains(object);
}
bool Heap::InToSpace(Object* object) {
return new_space_.ToSpaceContains(object);
}
bool Heap::InOldPointerSpace(Address address) {
return old_pointer_space_->Contains(address);
}
bool Heap::InOldPointerSpace(Object* object) {
return InOldPointerSpace(reinterpret_cast<Address>(object));
}
bool Heap::InOldDataSpace(Address address) {
return old_data_space_->Contains(address);
}
bool Heap::InOldDataSpace(Object* object) {
return InOldDataSpace(reinterpret_cast<Address>(object));
}
bool Heap::OldGenerationAllocationLimitReached() {
if (!incremental_marking()->IsStopped()) return false;
return OldGenerationSpaceAvailable() < 0;
}
bool Heap::ShouldBePromoted(Address old_address, int object_size) {
// An object should be promoted if:
// - the object has survived a scavenge operation or
// - to space is already 25% full.
NewSpacePage* page = NewSpacePage::FromAddress(old_address);
Address age_mark = new_space_.age_mark();
bool below_mark = page->IsFlagSet(MemoryChunk::NEW_SPACE_BELOW_AGE_MARK) &&
(!page->ContainsLimit(age_mark) || old_address < age_mark);
return below_mark || (new_space_.Size() + object_size) >=
(new_space_.EffectiveCapacity() >> 2);
}
void Heap::RecordWrite(Address address, int offset) {
if (!InNewSpace(address)) store_buffer_.Mark(address + offset);
}
void Heap::RecordWrites(Address address, int start, int len) {
if (!InNewSpace(address)) {
for (int i = 0; i < len; i++) {
store_buffer_.Mark(address + start + i * kPointerSize);
}
}
}
OldSpace* Heap::TargetSpace(HeapObject* object) {
InstanceType type = object->map()->instance_type();
AllocationSpace space = TargetSpaceId(type);
return (space == OLD_POINTER_SPACE)
? old_pointer_space_
: old_data_space_;
}
AllocationSpace Heap::TargetSpaceId(InstanceType type) {
// Heap numbers and sequential strings are promoted to old data space, all
// other object types are promoted to old pointer space. We do not use
// object->IsHeapNumber() and object->IsSeqString() because we already
// know that object has the heap object tag.
// These objects are never allocated in new space.
ASSERT(type != MAP_TYPE);
ASSERT(type != CODE_TYPE);
ASSERT(type != ODDBALL_TYPE);
ASSERT(type != CELL_TYPE);
ASSERT(type != PROPERTY_CELL_TYPE);
if (type <= LAST_NAME_TYPE) {
if (type == SYMBOL_TYPE) return OLD_POINTER_SPACE;
ASSERT(type < FIRST_NONSTRING_TYPE);
// There are four string representations: sequential strings, external
// strings, cons strings, and sliced strings.
// Only the latter two contain non-map-word pointers to heap objects.
return ((type & kIsIndirectStringMask) == kIsIndirectStringTag)
? OLD_POINTER_SPACE
: OLD_DATA_SPACE;
} else {
return (type <= LAST_DATA_TYPE) ? OLD_DATA_SPACE : OLD_POINTER_SPACE;
}
}
bool Heap::AllowedToBeMigrated(HeapObject* object, AllocationSpace dst) {
// Object migration is governed by the following rules:
//
// 1) Objects in new-space can be migrated to one of the old spaces
// that matches their target space or they stay in new-space.
// 2) Objects in old-space stay in the same space when migrating.
// 3) Fillers (two or more words) can migrate due to left-trimming of
// fixed arrays in new-space, old-data-space and old-pointer-space.
// 4) Fillers (one word) can never migrate, they are skipped by
// incremental marking explicitly to prevent invalid pattern.
//
// Since this function is used for debugging only, we do not place
// asserts here, but check everything explicitly.
if (object->map() == one_pointer_filler_map()) return false;
InstanceType type = object->map()->instance_type();
MemoryChunk* chunk = MemoryChunk::FromAddress(object->address());
AllocationSpace src = chunk->owner()->identity();
switch (src) {
case NEW_SPACE:
return dst == src || dst == TargetSpaceId(type);
case OLD_POINTER_SPACE:
return dst == src && (dst == TargetSpaceId(type) || object->IsFiller());
case OLD_DATA_SPACE:
return dst == src && dst == TargetSpaceId(type);
case CODE_SPACE:
return dst == src && type == CODE_TYPE;
case MAP_SPACE:
case CELL_SPACE:
case PROPERTY_CELL_SPACE:
case LO_SPACE:
return false;
}
UNREACHABLE();
return false;
}
void Heap::CopyBlock(Address dst, Address src, int byte_size) {
CopyWords(reinterpret_cast<Object**>(dst),
reinterpret_cast<Object**>(src),
static_cast<size_t>(byte_size / kPointerSize));
}
void Heap::MoveBlock(Address dst, Address src, int byte_size) {
ASSERT(IsAligned(byte_size, kPointerSize));
int size_in_words = byte_size / kPointerSize;
if ((dst < src) || (dst >= (src + byte_size))) {
Object** src_slot = reinterpret_cast<Object**>(src);
Object** dst_slot = reinterpret_cast<Object**>(dst);
Object** end_slot = src_slot + size_in_words;
while (src_slot != end_slot) {
*dst_slot++ = *src_slot++;
}
} else {
OS::MemMove(dst, src, static_cast<size_t>(byte_size));
}
}
void Heap::ScavengePointer(HeapObject** p) {
ScavengeObject(p, *p);
}
void Heap::ScavengeObject(HeapObject** p, HeapObject* object) {
ASSERT(object->GetIsolate()->heap()->InFromSpace(object));
// We use the first word (where the map pointer usually is) of a heap
// object to record the forwarding pointer. A forwarding pointer can
// point to an old space, the code space, or the to space of the new
// generation.
MapWord first_word = object->map_word();
// If the first word is a forwarding address, the object has already been
// copied.
if (first_word.IsForwardingAddress()) {
HeapObject* dest = first_word.ToForwardingAddress();
ASSERT(object->GetIsolate()->heap()->InFromSpace(*p));
*p = dest;
return;
}
if (FLAG_trace_track_allocation_sites && object->IsJSObject()) {
if (AllocationMemento::FindForJSObject(JSObject::cast(object), true) !=
NULL) {
object->GetIsolate()->heap()->allocation_mementos_found_++;
}
}
// AllocationMementos are unrooted and shouldn't survive a scavenge
ASSERT(object->map() != object->GetHeap()->allocation_memento_map());
// Call the slow part of scavenge object.
return ScavengeObjectSlow(p, object);
}
bool Heap::CollectGarbage(AllocationSpace space, const char* gc_reason) {
const char* collector_reason = NULL;
GarbageCollector collector = SelectGarbageCollector(space, &collector_reason);
return CollectGarbage(space, collector, gc_reason, collector_reason);
}
MaybeObject* Heap::PrepareForCompare(String* str) {
// Always flatten small strings and force flattening of long strings
// after we have accumulated a certain amount we failed to flatten.
static const int kMaxAlwaysFlattenLength = 32;
static const int kFlattenLongThreshold = 16*KB;
const int length = str->length();
MaybeObject* obj = str->TryFlatten();
if (length <= kMaxAlwaysFlattenLength ||
unflattened_strings_length_ >= kFlattenLongThreshold) {
return obj;
}
if (obj->IsFailure()) {
unflattened_strings_length_ += length;
}
return str;
}
intptr_t Heap::AdjustAmountOfExternalAllocatedMemory(
intptr_t change_in_bytes) {
ASSERT(HasBeenSetUp());
intptr_t amount = amount_of_external_allocated_memory_ + change_in_bytes;
if (change_in_bytes > 0) {
// Avoid overflow.
if (amount > amount_of_external_allocated_memory_) {
amount_of_external_allocated_memory_ = amount;
} else {
// Give up and reset the counters in case of an overflow.
amount_of_external_allocated_memory_ = 0;
amount_of_external_allocated_memory_at_last_global_gc_ = 0;
}
intptr_t amount_since_last_global_gc = PromotedExternalMemorySize();
if (amount_since_last_global_gc > external_allocation_limit_) {
CollectAllGarbage(kNoGCFlags, "external memory allocation limit reached");
}
} else {
// Avoid underflow.
if (amount >= 0) {
amount_of_external_allocated_memory_ = amount;
} else {
// Give up and reset the counters in case of an underflow.
amount_of_external_allocated_memory_ = 0;
amount_of_external_allocated_memory_at_last_global_gc_ = 0;
}
}
if (FLAG_trace_external_memory) {
PrintPID("%8.0f ms: ", isolate()->time_millis_since_init());
PrintF("Adjust amount of external memory: delta=%6" V8_PTR_PREFIX "d KB, "
"amount=%6" V8_PTR_PREFIX "d KB, since_gc=%6" V8_PTR_PREFIX "d KB, "
"isolate=0x%08" V8PRIxPTR ".\n",
change_in_bytes / KB,
amount_of_external_allocated_memory_ / KB,
PromotedExternalMemorySize() / KB,
reinterpret_cast<intptr_t>(isolate()));
}
ASSERT(amount_of_external_allocated_memory_ >= 0);
return amount_of_external_allocated_memory_;
}
Isolate* Heap::isolate() {
return reinterpret_cast<Isolate*>(reinterpret_cast<intptr_t>(this) -
reinterpret_cast<size_t>(reinterpret_cast<Isolate*>(4)->heap()) + 4);
}
#ifdef DEBUG
#define GC_GREEDY_CHECK(ISOLATE) \
if (FLAG_gc_greedy) (ISOLATE)->heap()->GarbageCollectionGreedyCheck()
#else
#define GC_GREEDY_CHECK(ISOLATE) { }
#endif
// Calls the FUNCTION_CALL function and retries it up to three times
// to guarantee that any allocations performed during the call will
// succeed if there's enough memory.
// Warning: Do not use the identifiers __object__, __maybe_object__ or
// __scope__ in a call to this macro.
#define CALL_AND_RETRY(ISOLATE, FUNCTION_CALL, RETURN_VALUE, RETURN_EMPTY, OOM)\
do { \
GC_GREEDY_CHECK(ISOLATE); \
MaybeObject* __maybe_object__ = FUNCTION_CALL; \
Object* __object__ = NULL; \
if (__maybe_object__->ToObject(&__object__)) RETURN_VALUE; \
if (__maybe_object__->IsOutOfMemory()) { \
OOM; \
} \
if (!__maybe_object__->IsRetryAfterGC()) RETURN_EMPTY; \
(ISOLATE)->heap()->CollectGarbage(Failure::cast(__maybe_object__)-> \
allocation_space(), \
"allocation failure"); \
__maybe_object__ = FUNCTION_CALL; \
if (__maybe_object__->ToObject(&__object__)) RETURN_VALUE; \
if (__maybe_object__->IsOutOfMemory()) { \
OOM; \
} \
if (!__maybe_object__->IsRetryAfterGC()) RETURN_EMPTY; \
(ISOLATE)->counters()->gc_last_resort_from_handles()->Increment(); \
(ISOLATE)->heap()->CollectAllAvailableGarbage("last resort gc"); \
{ \
AlwaysAllocateScope __scope__; \
__maybe_object__ = FUNCTION_CALL; \
} \
if (__maybe_object__->ToObject(&__object__)) RETURN_VALUE; \
if (__maybe_object__->IsOutOfMemory()) { \
OOM; \
} \
if (__maybe_object__->IsRetryAfterGC()) { \
/* TODO(1181417): Fix this. */ \
v8::internal::V8::FatalProcessOutOfMemory("CALL_AND_RETRY_LAST", true); \
} \
RETURN_EMPTY; \
} while (false)
#define CALL_AND_RETRY_OR_DIE( \
ISOLATE, FUNCTION_CALL, RETURN_VALUE, RETURN_EMPTY) \
CALL_AND_RETRY( \
ISOLATE, \
FUNCTION_CALL, \
RETURN_VALUE, \
RETURN_EMPTY, \
v8::internal::V8::FatalProcessOutOfMemory("CALL_AND_RETRY", true))
#define CALL_HEAP_FUNCTION(ISOLATE, FUNCTION_CALL, TYPE) \
CALL_AND_RETRY_OR_DIE(ISOLATE, \
FUNCTION_CALL, \
return Handle<TYPE>(TYPE::cast(__object__), ISOLATE), \
return Handle<TYPE>()) \
#define CALL_HEAP_FUNCTION_VOID(ISOLATE, FUNCTION_CALL) \
CALL_AND_RETRY_OR_DIE(ISOLATE, FUNCTION_CALL, return, return)
#define CALL_HEAP_FUNCTION_PASS_EXCEPTION(ISOLATE, FUNCTION_CALL) \
CALL_AND_RETRY(ISOLATE, \
FUNCTION_CALL, \
return __object__, \
return __maybe_object__, \
return __maybe_object__)
void ExternalStringTable::AddString(String* string) {
ASSERT(string->IsExternalString());
if (heap_->InNewSpace(string)) {
new_space_strings_.Add(string);
} else {
old_space_strings_.Add(string);
}
}
void ExternalStringTable::Iterate(ObjectVisitor* v) {
if (!new_space_strings_.is_empty()) {
Object** start = &new_space_strings_[0];
v->VisitPointers(start, start + new_space_strings_.length());
}
if (!old_space_strings_.is_empty()) {
Object** start = &old_space_strings_[0];
v->VisitPointers(start, start + old_space_strings_.length());
}
}
// Verify() is inline to avoid ifdef-s around its calls in release
// mode.
void ExternalStringTable::Verify() {
#ifdef DEBUG
for (int i = 0; i < new_space_strings_.length(); ++i) {
Object* obj = Object::cast(new_space_strings_[i]);
ASSERT(heap_->InNewSpace(obj));
ASSERT(obj != heap_->the_hole_value());
}
for (int i = 0; i < old_space_strings_.length(); ++i) {
Object* obj = Object::cast(old_space_strings_[i]);
ASSERT(!heap_->InNewSpace(obj));
ASSERT(obj != heap_->the_hole_value());
}
#endif
}
void ExternalStringTable::AddOldString(String* string) {
ASSERT(string->IsExternalString());
ASSERT(!heap_->InNewSpace(string));
old_space_strings_.Add(string);
}
void ExternalStringTable::ShrinkNewStrings(int position) {
new_space_strings_.Rewind(position);
#ifdef VERIFY_HEAP
if (FLAG_verify_heap) {
Verify();
}
#endif
}
void Heap::ClearInstanceofCache() {
set_instanceof_cache_function(the_hole_value());
}
Object* Heap::ToBoolean(bool condition) {
return condition ? true_value() : false_value();
}
void Heap::CompletelyClearInstanceofCache() {
set_instanceof_cache_map(the_hole_value());
set_instanceof_cache_function(the_hole_value());
}
MaybeObject* TranscendentalCache::Get(Type type, double input) {
SubCache* cache = caches_[type];
if (cache == NULL) {
caches_[type] = cache = new SubCache(isolate_, type);
}
return cache->Get(input);
}
Address TranscendentalCache::cache_array_address() {
return reinterpret_cast<Address>(caches_);
}
double TranscendentalCache::SubCache::Calculate(double input) {
switch (type_) {
case ACOS:
return acos(input);
case ASIN:
return asin(input);
case ATAN:
return atan(input);
case COS:
return fast_cos(input);
case EXP:
return exp(input);
case LOG:
return fast_log(input);
case SIN:
return fast_sin(input);
case TAN:
return fast_tan(input);
default:
return 0.0; // Never happens.
}
}
MaybeObject* TranscendentalCache::SubCache::Get(double input) {
Converter c;
c.dbl = input;
int hash = Hash(c);
Element e = elements_[hash];
if (e.in[0] == c.integers[0] &&
e.in[1] == c.integers[1]) {
ASSERT(e.output != NULL);
isolate_->counters()->transcendental_cache_hit()->Increment();
return e.output;
}
double answer = Calculate(input);
isolate_->counters()->transcendental_cache_miss()->Increment();
Object* heap_number;
{ MaybeObject* maybe_heap_number =
isolate_->heap()->AllocateHeapNumber(answer);
if (!maybe_heap_number->ToObject(&heap_number)) return maybe_heap_number;
}
elements_[hash].in[0] = c.integers[0];
elements_[hash].in[1] = c.integers[1];
elements_[hash].output = heap_number;
return heap_number;
}
AlwaysAllocateScope::AlwaysAllocateScope() {
// We shouldn't hit any nested scopes, because that requires
// non-handle code to call handle code. The code still works but
// performance will degrade, so we want to catch this situation
// in debug mode.
Isolate* isolate = Isolate::Current();
ASSERT(isolate->heap()->always_allocate_scope_depth_ == 0);
isolate->heap()->always_allocate_scope_depth_++;
}
AlwaysAllocateScope::~AlwaysAllocateScope() {
Isolate* isolate = Isolate::Current();
isolate->heap()->always_allocate_scope_depth_--;
ASSERT(isolate->heap()->always_allocate_scope_depth_ == 0);
}
#ifdef VERIFY_HEAP
NoWeakObjectVerificationScope::NoWeakObjectVerificationScope() {
Isolate* isolate = Isolate::Current();
isolate->heap()->no_weak_object_verification_scope_depth_++;
}
NoWeakObjectVerificationScope::~NoWeakObjectVerificationScope() {
Isolate* isolate = Isolate::Current();
isolate->heap()->no_weak_object_verification_scope_depth_--;
}
#endif
void VerifyPointersVisitor::VisitPointers(Object** start, Object** end) {
for (Object** current = start; current < end; current++) {
if ((*current)->IsHeapObject()) {
HeapObject* object = HeapObject::cast(*current);
CHECK(object->GetIsolate()->heap()->Contains(object));
CHECK(object->map()->IsMap());
}
}
}
double GCTracer::SizeOfHeapObjects() {
return (static_cast<double>(heap_->SizeOfObjects())) / MB;
}
DisallowAllocationFailure::DisallowAllocationFailure() {
#ifdef DEBUG
Isolate* isolate = Isolate::Current();
old_state_ = isolate->heap()->disallow_allocation_failure_;
isolate->heap()->disallow_allocation_failure_ = true;
#endif
}
DisallowAllocationFailure::~DisallowAllocationFailure() {
#ifdef DEBUG
Isolate* isolate = Isolate::Current();
isolate->heap()->disallow_allocation_failure_ = old_state_;
#endif
}
} } // namespace v8::internal
#endif // V8_HEAP_INL_H_
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