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// Copyright 2011 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#ifndef V8_HEAP_SPACES_INL_H_
#define V8_HEAP_SPACES_INL_H_
#include "src/heap/spaces.h"
#include "src/isolate.h"
#include "src/msan.h"
#include "src/profiler/heap-profiler.h"
#include "src/v8memory.h"
namespace v8 {
namespace internal {
// -----------------------------------------------------------------------------
// Bitmap
void Bitmap::Clear(MemoryChunk* chunk) {
Bitmap* bitmap = chunk->markbits();
for (int i = 0; i < bitmap->CellsCount(); i++) bitmap->cells()[i] = 0;
chunk->ResetLiveBytes();
}
// -----------------------------------------------------------------------------
// PageIterator
PageIterator::PageIterator(PagedSpace* space)
: space_(space),
prev_page_(&space->anchor_),
next_page_(prev_page_->next_page()) {}
bool PageIterator::has_next() { return next_page_ != &space_->anchor_; }
Page* PageIterator::next() {
DCHECK(has_next());
prev_page_ = next_page_;
next_page_ = next_page_->next_page();
return prev_page_;
}
// -----------------------------------------------------------------------------
// SemiSpaceIterator
HeapObject* SemiSpaceIterator::Next() {
if (current_ == limit_) return NULL;
if (NewSpacePage::IsAtEnd(current_)) {
NewSpacePage* page = NewSpacePage::FromLimit(current_);
page = page->next_page();
DCHECK(!page->is_anchor());
current_ = page->area_start();
if (current_ == limit_) return NULL;
}
HeapObject* object = HeapObject::FromAddress(current_);
int size = object->Size();
current_ += size;
return object;
}
HeapObject* SemiSpaceIterator::next_object() { return Next(); }
// -----------------------------------------------------------------------------
// NewSpacePageIterator
NewSpacePageIterator::NewSpacePageIterator(NewSpace* space)
: prev_page_(NewSpacePage::FromAddress(space->ToSpaceStart())->prev_page()),
next_page_(NewSpacePage::FromAddress(space->ToSpaceStart())),
last_page_(NewSpacePage::FromLimit(space->ToSpaceEnd())) {}
NewSpacePageIterator::NewSpacePageIterator(SemiSpace* space)
: prev_page_(space->anchor()),
next_page_(prev_page_->next_page()),
last_page_(prev_page_->prev_page()) {}
NewSpacePageIterator::NewSpacePageIterator(Address start, Address limit)
: prev_page_(NewSpacePage::FromAddress(start)->prev_page()),
next_page_(NewSpacePage::FromAddress(start)),
last_page_(NewSpacePage::FromLimit(limit)) {
SemiSpace::AssertValidRange(start, limit);
}
bool NewSpacePageIterator::has_next() { return prev_page_ != last_page_; }
NewSpacePage* NewSpacePageIterator::next() {
DCHECK(has_next());
prev_page_ = next_page_;
next_page_ = next_page_->next_page();
return prev_page_;
}
// -----------------------------------------------------------------------------
// HeapObjectIterator
HeapObject* HeapObjectIterator::Next() {
do {
HeapObject* next_obj = FromCurrentPage();
if (next_obj != NULL) return next_obj;
} while (AdvanceToNextPage());
return NULL;
}
HeapObject* HeapObjectIterator::next_object() { return Next(); }
HeapObject* HeapObjectIterator::FromCurrentPage() {
while (cur_addr_ != cur_end_) {
if (cur_addr_ == space_->top() && cur_addr_ != space_->limit()) {
cur_addr_ = space_->limit();
continue;
}
HeapObject* obj = HeapObject::FromAddress(cur_addr_);
int obj_size = obj->Size();
cur_addr_ += obj_size;
DCHECK(cur_addr_ <= cur_end_);
// TODO(hpayer): Remove the debugging code.
if (cur_addr_ > cur_end_) {
space_->heap()->isolate()->PushStackTraceAndDie(0xaaaaaaaa, obj, NULL,
obj_size);
}
if (!obj->IsFiller()) {
DCHECK_OBJECT_SIZE(obj_size);
return obj;
}
}
return NULL;
}
// -----------------------------------------------------------------------------
// MemoryAllocator
#ifdef ENABLE_HEAP_PROTECTION
void MemoryAllocator::Protect(Address start, size_t size) {
base::OS::Protect(start, size);
}
void MemoryAllocator::Unprotect(Address start, size_t size,
Executability executable) {
base::OS::Unprotect(start, size, executable);
}
void MemoryAllocator::ProtectChunkFromPage(Page* page) {
int id = GetChunkId(page);
base::OS::Protect(chunks_[id].address(), chunks_[id].size());
}
void MemoryAllocator::UnprotectChunkFromPage(Page* page) {
int id = GetChunkId(page);
base::OS::Unprotect(chunks_[id].address(), chunks_[id].size(),
chunks_[id].owner()->executable() == EXECUTABLE);
}
#endif
// --------------------------------------------------------------------------
// AllocationResult
AllocationSpace AllocationResult::RetrySpace() {
DCHECK(IsRetry());
return static_cast<AllocationSpace>(Smi::cast(object_)->value());
}
// --------------------------------------------------------------------------
// PagedSpace
Page* Page::Initialize(Heap* heap, MemoryChunk* chunk, Executability executable,
PagedSpace* owner) {
Page* page = reinterpret_cast<Page*>(chunk);
page->mutex_ = new base::Mutex();
DCHECK(page->area_size() <= kMaxRegularHeapObjectSize);
DCHECK(chunk->owner() == owner);
owner->IncreaseCapacity(page->area_size());
owner->Free(page->area_start(), page->area_size());
heap->incremental_marking()->SetOldSpacePageFlags(chunk);
return page;
}
bool PagedSpace::Contains(Address addr) {
Page* p = Page::FromAddress(addr);
if (!p->is_valid()) return false;
return p->owner() == this;
}
bool PagedSpace::Contains(HeapObject* o) { return Contains(o->address()); }
void MemoryChunk::set_scan_on_scavenge(bool scan) {
if (scan) {
if (!scan_on_scavenge()) heap_->increment_scan_on_scavenge_pages();
SetFlag(SCAN_ON_SCAVENGE);
} else {
if (scan_on_scavenge()) heap_->decrement_scan_on_scavenge_pages();
ClearFlag(SCAN_ON_SCAVENGE);
}
heap_->incremental_marking()->SetOldSpacePageFlags(this);
}
MemoryChunk* MemoryChunk::FromAnyPointerAddress(Heap* heap, Address addr) {
MemoryChunk* maybe = reinterpret_cast<MemoryChunk*>(
OffsetFrom(addr) & ~Page::kPageAlignmentMask);
if (maybe->owner() != NULL) return maybe;
LargeObjectIterator iterator(heap->lo_space());
for (HeapObject* o = iterator.Next(); o != NULL; o = iterator.Next()) {
// Fixed arrays are the only pointer-containing objects in large object
// space.
if (o->IsFixedArray()) {
MemoryChunk* chunk = MemoryChunk::FromAddress(o->address());
if (chunk->Contains(addr)) {
return chunk;
}
}
}
UNREACHABLE();
return NULL;
}
PointerChunkIterator::PointerChunkIterator(Heap* heap)
: state_(kOldSpaceState),
old_iterator_(heap->old_space()),
map_iterator_(heap->map_space()),
lo_iterator_(heap->lo_space()) {}
MemoryChunk* PointerChunkIterator::next() {
switch (state_) {
case kOldSpaceState: {
if (old_iterator_.has_next()) {
return old_iterator_.next();
}
state_ = kMapState;
// Fall through.
}
case kMapState: {
if (map_iterator_.has_next()) {
return map_iterator_.next();
}
state_ = kLargeObjectState;
// Fall through.
}
case kLargeObjectState: {
HeapObject* heap_object;
do {
heap_object = lo_iterator_.Next();
if (heap_object == NULL) {
state_ = kFinishedState;
return NULL;
}
// Fixed arrays are the only pointer-containing objects in large
// object space.
} while (!heap_object->IsFixedArray());
MemoryChunk* answer = MemoryChunk::FromAddress(heap_object->address());
return answer;
}
case kFinishedState:
return NULL;
default:
break;
}
UNREACHABLE();
return NULL;
}
void Page::set_next_page(Page* page) {
DCHECK(page->owner() == owner());
set_next_chunk(page);
}
void Page::set_prev_page(Page* page) {
DCHECK(page->owner() == owner());
set_prev_chunk(page);
}
// Try linear allocation in the page of alloc_info's allocation top. Does
// not contain slow case logic (e.g. move to the next page or try free list
// allocation) so it can be used by all the allocation functions and for all
// the paged spaces.
HeapObject* PagedSpace::AllocateLinearly(int size_in_bytes) {
Address current_top = allocation_info_.top();
Address new_top = current_top + size_in_bytes;
if (new_top > allocation_info_.limit()) return NULL;
allocation_info_.set_top(new_top);
return HeapObject::FromAddress(current_top);
}
HeapObject* PagedSpace::AllocateLinearlyAligned(int* size_in_bytes,
AllocationAlignment alignment) {
Address current_top = allocation_info_.top();
int filler_size = Heap::GetFillToAlign(current_top, alignment);
Address new_top = current_top + filler_size + *size_in_bytes;
if (new_top > allocation_info_.limit()) return NULL;
allocation_info_.set_top(new_top);
if (filler_size > 0) {
*size_in_bytes += filler_size;
return heap()->PrecedeWithFiller(HeapObject::FromAddress(current_top),
filler_size);
}
return HeapObject::FromAddress(current_top);
}
// Raw allocation.
AllocationResult PagedSpace::AllocateRawUnaligned(int size_in_bytes) {
HeapObject* object = AllocateLinearly(size_in_bytes);
if (object == NULL) {
object = free_list_.Allocate(size_in_bytes);
if (object == NULL) {
object = SlowAllocateRaw(size_in_bytes);
}
}
if (object != NULL) {
if (identity() == CODE_SPACE) {
SkipList::Update(object->address(), size_in_bytes);
}
MSAN_ALLOCATED_UNINITIALIZED_MEMORY(object->address(), size_in_bytes);
return object;
}
return AllocationResult::Retry(identity());
}
AllocationResult PagedSpace::AllocateRawUnalignedSynchronized(
int size_in_bytes) {
base::LockGuard<base::Mutex> lock_guard(&space_mutex_);
return AllocateRawUnaligned(size_in_bytes);
}
// Raw allocation.
AllocationResult PagedSpace::AllocateRawAligned(int size_in_bytes,
AllocationAlignment alignment) {
DCHECK(identity() == OLD_SPACE);
int allocation_size = size_in_bytes;
HeapObject* object = AllocateLinearlyAligned(&allocation_size, alignment);
if (object == NULL) {
// We don't know exactly how much filler we need to align until space is
// allocated, so assume the worst case.
int filler_size = Heap::GetMaximumFillToAlign(alignment);
allocation_size += filler_size;
object = free_list_.Allocate(allocation_size);
if (object == NULL) {
object = SlowAllocateRaw(allocation_size);
}
if (object != NULL && filler_size != 0) {
object = heap()->AlignWithFiller(object, size_in_bytes, allocation_size,
alignment);
// Filler objects are initialized, so mark only the aligned object memory
// as uninitialized.
allocation_size = size_in_bytes;
}
}
if (object != NULL) {
MSAN_ALLOCATED_UNINITIALIZED_MEMORY(object->address(), allocation_size);
return object;
}
return AllocationResult::Retry(identity());
}
AllocationResult PagedSpace::AllocateRaw(int size_in_bytes,
AllocationAlignment alignment) {
#ifdef V8_HOST_ARCH_32_BIT
return alignment == kDoubleAligned
? AllocateRawAligned(size_in_bytes, kDoubleAligned)
: AllocateRawUnaligned(size_in_bytes);
#else
return AllocateRawUnaligned(size_in_bytes);
#endif
}
// -----------------------------------------------------------------------------
// NewSpace
AllocationResult NewSpace::AllocateRawAligned(int size_in_bytes,
AllocationAlignment alignment) {
Address top = allocation_info_.top();
int filler_size = Heap::GetFillToAlign(top, alignment);
int aligned_size_in_bytes = size_in_bytes + filler_size;
if (allocation_info_.limit() - top < aligned_size_in_bytes) {
// See if we can create room.
if (!EnsureAllocation(size_in_bytes, alignment)) {
return AllocationResult::Retry();
}
top = allocation_info_.top();
filler_size = Heap::GetFillToAlign(top, alignment);
aligned_size_in_bytes = size_in_bytes + filler_size;
}
HeapObject* obj = HeapObject::FromAddress(top);
allocation_info_.set_top(top + aligned_size_in_bytes);
DCHECK_SEMISPACE_ALLOCATION_INFO(allocation_info_, to_space_);
if (filler_size > 0) {
obj = heap()->PrecedeWithFiller(obj, filler_size);
}
MSAN_ALLOCATED_UNINITIALIZED_MEMORY(obj->address(), size_in_bytes);
return obj;
}
AllocationResult NewSpace::AllocateRawUnaligned(int size_in_bytes) {
Address top = allocation_info_.top();
if (allocation_info_.limit() - top < size_in_bytes) {
// See if we can create room.
if (!EnsureAllocation(size_in_bytes, kWordAligned)) {
return AllocationResult::Retry();
}
top = allocation_info_.top();
}
HeapObject* obj = HeapObject::FromAddress(top);
allocation_info_.set_top(top + size_in_bytes);
DCHECK_SEMISPACE_ALLOCATION_INFO(allocation_info_, to_space_);
MSAN_ALLOCATED_UNINITIALIZED_MEMORY(obj->address(), size_in_bytes);
return obj;
}
AllocationResult NewSpace::AllocateRaw(int size_in_bytes,
AllocationAlignment alignment) {
#ifdef V8_HOST_ARCH_32_BIT
return alignment == kDoubleAligned
? AllocateRawAligned(size_in_bytes, kDoubleAligned)
: AllocateRawUnaligned(size_in_bytes);
#else
return AllocateRawUnaligned(size_in_bytes);
#endif
}
LargePage* LargePage::Initialize(Heap* heap, MemoryChunk* chunk) {
heap->incremental_marking()->SetOldSpacePageFlags(chunk);
return static_cast<LargePage*>(chunk);
}
intptr_t LargeObjectSpace::Available() {
return ObjectSizeFor(heap()->isolate()->memory_allocator()->Available());
}
}
} // namespace v8::internal
#endif // V8_HEAP_SPACES_INL_H_
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