| // Copyright 2006-2010 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 "objects.h" |
| #include "v8-counters.h" |
| |
| namespace v8 { |
| namespace internal { |
| |
| int Heap::MaxObjectSizeInPagedSpace() { |
| return Page::kMaxHeapObjectSize; |
| } |
| |
| |
| MaybeObject* Heap::AllocateStringFromUtf8(Vector<const char> str, |
| PretenureFlag pretenure) { |
| // Check for ASCII first since this is the common case. |
| if (String::IsAscii(str.start(), str.length())) { |
| // If the string is ASCII, we do not need to convert the characters |
| // since UTF8 is backwards compatible with ASCII. |
| return AllocateStringFromAscii(str, pretenure); |
| } |
| // Non-ASCII and we need to decode. |
| return AllocateStringFromUtf8Slow(str, pretenure); |
| } |
| |
| |
| MaybeObject* Heap::AllocateSymbol(Vector<const char> str, |
| int chars, |
| uint32_t hash_field) { |
| unibrow::Utf8InputBuffer<> buffer(str.start(), |
| static_cast<unsigned>(str.length())); |
| return AllocateInternalSymbol(&buffer, chars, hash_field); |
| } |
| |
| |
| MaybeObject* Heap::AllocateAsciiSymbol(Vector<const char> str, |
| uint32_t hash_field) { |
| if (str.length() > SeqAsciiString::kMaxLength) { |
| return Failure::OutOfMemoryException(); |
| } |
| // Compute map and object size. |
| Map* map = ascii_symbol_map(); |
| int size = SeqAsciiString::SizeFor(str.length()); |
| |
| // Allocate string. |
| Object* result; |
| { MaybeObject* maybe_result = (size > MaxObjectSizeInPagedSpace()) |
| ? lo_space_->AllocateRaw(size) |
| : old_data_space_->AllocateRaw(size); |
| 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. |
| memcpy(answer->address() + SeqAsciiString::kHeaderSize, |
| str.start(), str.length()); |
| |
| return answer; |
| } |
| |
| |
| MaybeObject* Heap::AllocateTwoByteSymbol(Vector<const uc16> str, |
| uint32_t hash_field) { |
| if (str.length() > SeqTwoByteString::kMaxLength) { |
| return Failure::OutOfMemoryException(); |
| } |
| // Compute map and object size. |
| Map* map = symbol_map(); |
| int size = SeqTwoByteString::SizeFor(str.length()); |
| |
| // Allocate string. |
| Object* result; |
| { MaybeObject* maybe_result = (size > MaxObjectSizeInPagedSpace()) |
| ? lo_space_->AllocateRaw(size) |
| : old_data_space_->AllocateRaw(size); |
| 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. |
| memcpy(answer->address() + SeqTwoByteString::kHeaderSize, |
| str.start(), str.length() * kUC16Size); |
| |
| return answer; |
| } |
| |
| MaybeObject* Heap::CopyFixedArray(FixedArray* src) { |
| return CopyFixedArrayWithMap(src, src->map()); |
| } |
| |
| |
| MaybeObject* Heap::AllocateRaw(int size_in_bytes, |
| AllocationSpace space, |
| AllocationSpace retry_space) { |
| ASSERT(allocation_allowed_ && gc_state_ == NOT_IN_GC); |
| ASSERT(space != NEW_SPACE || |
| retry_space == OLD_POINTER_SPACE || |
| retry_space == OLD_DATA_SPACE || |
| retry_space == LO_SPACE); |
| #ifdef DEBUG |
| if (FLAG_gc_interval >= 0 && |
| !disallow_allocation_failure_ && |
| Heap::allocation_timeout_-- <= 0) { |
| return Failure::RetryAfterGC(space); |
| } |
| Counters::objs_since_last_full.Increment(); |
| Counters::objs_since_last_young.Increment(); |
| #endif |
| MaybeObject* result; |
| if (NEW_SPACE == space) { |
| result = new_space_.AllocateRaw(size_in_bytes); |
| if (always_allocate() && result->IsFailure()) { |
| space = retry_space; |
| } else { |
| 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); |
| } else if (CELL_SPACE == space) { |
| result = 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; |
| return result; |
| } |
| |
| |
| MaybeObject* Heap::NumberFromInt32(int32_t value) { |
| if (Smi::IsValid(value)) return Smi::FromInt(value); |
| // Bypass NumberFromDouble to avoid various redundant checks. |
| return AllocateHeapNumber(FastI2D(value)); |
| } |
| |
| |
| MaybeObject* Heap::NumberFromUint32(uint32_t value) { |
| if ((int32_t)value >= 0 && Smi::IsValid((int32_t)value)) { |
| return Smi::FromInt((int32_t)value); |
| } |
| // Bypass NumberFromDouble to avoid various redundant checks. |
| return AllocateHeapNumber(FastUI2D(value)); |
| } |
| |
| |
| 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(); |
| } |
| |
| // Clear the resource pointer in the string. |
| *resource_addr = NULL; |
| } |
| |
| |
| MaybeObject* Heap::AllocateRawMap() { |
| #ifdef DEBUG |
| Counters::objs_since_last_full.Increment(); |
| Counters::objs_since_last_young.Increment(); |
| #endif |
| MaybeObject* result = map_space_->AllocateRaw(Map::kSize); |
| if (result->IsFailure()) old_gen_exhausted_ = true; |
| #ifdef DEBUG |
| if (!result->IsFailure()) { |
| // Maps have their own alignment. |
| CHECK((reinterpret_cast<intptr_t>(result) & kMapAlignmentMask) == |
| static_cast<intptr_t>(kHeapObjectTag)); |
| } |
| #endif |
| return result; |
| } |
| |
| |
| MaybeObject* Heap::AllocateRawCell() { |
| #ifdef DEBUG |
| Counters::objs_since_last_full.Increment(); |
| Counters::objs_since_last_young.Increment(); |
| #endif |
| MaybeObject* result = cell_space_->AllocateRaw(JSGlobalPropertyCell::kSize); |
| if (result->IsFailure()) old_gen_exhausted_ = true; |
| return result; |
| } |
| |
| |
| 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::InFromSpace(Object* object) { |
| return new_space_.FromSpaceContains(object); |
| } |
| |
| |
| bool Heap::InToSpace(Object* object) { |
| return new_space_.ToSpaceContains(object); |
| } |
| |
| |
| 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. |
| return old_address < new_space_.age_mark() |
| || (new_space_.Size() + object_size) >= (new_space_.Capacity() >> 2); |
| } |
| |
| |
| void Heap::RecordWrite(Address address, int offset) { |
| if (new_space_.Contains(address)) return; |
| ASSERT(!new_space_.FromSpaceContains(address)); |
| SLOW_ASSERT(Contains(address + offset)); |
| Page::FromAddress(address)->MarkRegionDirty(address + offset); |
| } |
| |
| |
| void Heap::RecordWrites(Address address, int start, int len) { |
| if (new_space_.Contains(address)) return; |
| ASSERT(!new_space_.FromSpaceContains(address)); |
| Page* page = Page::FromAddress(address); |
| page->SetRegionMarks(page->GetRegionMarks() | |
| page->GetRegionMaskForSpan(address + start, len * 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 != JS_GLOBAL_PROPERTY_CELL_TYPE); |
| |
| if (type < FIRST_NONSTRING_TYPE) { |
| // There are three string representations: sequential strings, cons |
| // strings, and external strings. Only cons strings contain |
| // non-map-word pointers to heap objects. |
| return ((type & kStringRepresentationMask) == kConsStringTag) |
| ? OLD_POINTER_SPACE |
| : OLD_DATA_SPACE; |
| } else { |
| return (type <= LAST_DATA_TYPE) ? OLD_DATA_SPACE : OLD_POINTER_SPACE; |
| } |
| } |
| |
| |
| void Heap::CopyBlock(Address dst, Address src, int byte_size) { |
| ASSERT(IsAligned(byte_size, kPointerSize)); |
| CopyWords(reinterpret_cast<Object**>(dst), |
| reinterpret_cast<Object**>(src), |
| byte_size / kPointerSize); |
| } |
| |
| |
| void Heap::CopyBlockToOldSpaceAndUpdateRegionMarks(Address dst, |
| Address src, |
| int byte_size) { |
| ASSERT(IsAligned(byte_size, kPointerSize)); |
| |
| Page* page = Page::FromAddress(dst); |
| uint32_t marks = page->GetRegionMarks(); |
| |
| for (int remaining = byte_size / kPointerSize; |
| remaining > 0; |
| remaining--) { |
| Memory::Object_at(dst) = Memory::Object_at(src); |
| |
| if (Heap::InNewSpace(Memory::Object_at(dst))) { |
| marks |= page->GetRegionMaskForAddress(dst); |
| } |
| |
| dst += kPointerSize; |
| src += kPointerSize; |
| } |
| |
| page->SetRegionMarks(marks); |
| } |
| |
| |
| 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 + size_in_words))) { |
| ASSERT((dst >= (src + size_in_words)) || |
| ((OffsetFrom(reinterpret_cast<Address>(src)) - |
| OffsetFrom(reinterpret_cast<Address>(dst))) >= kPointerSize)); |
| |
| 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 { |
| memmove(dst, src, byte_size); |
| } |
| } |
| |
| |
| void Heap::MoveBlockToOldSpaceAndUpdateRegionMarks(Address dst, |
| Address src, |
| int byte_size) { |
| ASSERT(IsAligned(byte_size, kPointerSize)); |
| ASSERT((dst >= (src + byte_size)) || |
| ((OffsetFrom(src) - OffsetFrom(dst)) >= kPointerSize)); |
| |
| CopyBlockToOldSpaceAndUpdateRegionMarks(dst, src, byte_size); |
| } |
| |
| |
| void Heap::ScavengeObject(HeapObject** p, HeapObject* object) { |
| ASSERT(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()) { |
| *p = first_word.ToForwardingAddress(); |
| return; |
| } |
| |
| // Call the slow part of scavenge object. |
| return ScavengeObjectSlow(p, object); |
| } |
| |
| |
| bool Heap::CollectGarbage(AllocationSpace space) { |
| return CollectGarbage(space, SelectGarbageCollector(space)); |
| } |
| |
| |
| 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; |
| } |
| |
| |
| int Heap::AdjustAmountOfExternalAllocatedMemory(int change_in_bytes) { |
| ASSERT(HasBeenSetup()); |
| int 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; |
| } |
| int amount_since_last_global_gc = |
| amount_of_external_allocated_memory_ - |
| amount_of_external_allocated_memory_at_last_global_gc_; |
| if (amount_since_last_global_gc > external_allocation_limit_) { |
| CollectAllGarbage(false); |
| } |
| } else { |
| // Avoid underflow. |
| if (amount >= 0) { |
| amount_of_external_allocated_memory_ = amount; |
| } |
| } |
| ASSERT(amount_of_external_allocated_memory_ >= 0); |
| return amount_of_external_allocated_memory_; |
| } |
| |
| |
| void Heap::SetLastScriptId(Object* last_script_id) { |
| roots_[kLastScriptIdRootIndex] = last_script_id; |
| } |
| |
| |
| #ifdef DEBUG |
| #define GC_GREEDY_CHECK() \ |
| if (FLAG_gc_greedy) v8::internal::Heap::GarbageCollectionGreedyCheck() |
| #else |
| #define GC_GREEDY_CHECK() { } |
| #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(FUNCTION_CALL, RETURN_VALUE, RETURN_EMPTY) \ |
| do { \ |
| GC_GREEDY_CHECK(); \ |
| MaybeObject* __maybe_object__ = FUNCTION_CALL; \ |
| Object* __object__ = NULL; \ |
| if (__maybe_object__->ToObject(&__object__)) RETURN_VALUE; \ |
| if (__maybe_object__->IsOutOfMemory()) { \ |
| v8::internal::V8::FatalProcessOutOfMemory("CALL_AND_RETRY_0", true);\ |
| } \ |
| if (!__maybe_object__->IsRetryAfterGC()) RETURN_EMPTY; \ |
| Heap::CollectGarbage( \ |
| Failure::cast(__maybe_object__)->allocation_space()); \ |
| __maybe_object__ = FUNCTION_CALL; \ |
| if (__maybe_object__->ToObject(&__object__)) RETURN_VALUE; \ |
| if (__maybe_object__->IsOutOfMemory()) { \ |
| v8::internal::V8::FatalProcessOutOfMemory("CALL_AND_RETRY_1", true);\ |
| } \ |
| if (!__maybe_object__->IsRetryAfterGC()) RETURN_EMPTY; \ |
| Counters::gc_last_resort_from_handles.Increment(); \ |
| Heap::CollectAllAvailableGarbage(); \ |
| { \ |
| AlwaysAllocateScope __scope__; \ |
| __maybe_object__ = FUNCTION_CALL; \ |
| } \ |
| if (__maybe_object__->ToObject(&__object__)) RETURN_VALUE; \ |
| if (__maybe_object__->IsOutOfMemory() || \ |
| __maybe_object__->IsRetryAfterGC()) { \ |
| /* TODO(1181417): Fix this. */ \ |
| v8::internal::V8::FatalProcessOutOfMemory("CALL_AND_RETRY_2", true);\ |
| } \ |
| RETURN_EMPTY; \ |
| } while (false) |
| |
| |
| #define CALL_HEAP_FUNCTION(FUNCTION_CALL, TYPE) \ |
| CALL_AND_RETRY(FUNCTION_CALL, \ |
| return Handle<TYPE>(TYPE::cast(__object__)), \ |
| return Handle<TYPE>()) |
| |
| |
| #define CALL_HEAP_FUNCTION_VOID(FUNCTION_CALL) \ |
| CALL_AND_RETRY(FUNCTION_CALL, return, return) |
| |
| |
| #ifdef DEBUG |
| |
| inline bool Heap::allow_allocation(bool new_state) { |
| bool old = allocation_allowed_; |
| allocation_allowed_ = new_state; |
| return old; |
| } |
| |
| #endif |
| |
| |
| 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) { |
| ASSERT(Heap::InNewSpace(new_space_strings_[i])); |
| ASSERT(new_space_strings_[i] != Heap::raw_unchecked_null_value()); |
| } |
| for (int i = 0; i < old_space_strings_.length(); ++i) { |
| ASSERT(!Heap::InNewSpace(old_space_strings_[i])); |
| ASSERT(old_space_strings_[i] != Heap::raw_unchecked_null_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); |
| Verify(); |
| } |
| |
| } } // namespace v8::internal |
| |
| #endif // V8_HEAP_INL_H_ |
