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// Copyright 2020 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_PAGED_SPACES_INL_H_
#define V8_HEAP_PAGED_SPACES_INL_H_
#include "src/common/globals.h"
#include "src/heap/heap-inl.h"
#include "src/heap/incremental-marking.h"
#include "src/heap/paged-spaces.h"
#include "src/objects/code-inl.h"
#include "src/objects/heap-object.h"
#include "src/objects/objects-inl.h"
namespace v8 {
namespace internal {
// -----------------------------------------------------------------------------
// PagedSpaceObjectIterator
HeapObject PagedSpaceObjectIterator::Next() {
do {
HeapObject next_obj = FromCurrentPage();
if (!next_obj.is_null()) return next_obj;
} while (AdvanceToNextPage());
return HeapObject();
}
HeapObject PagedSpaceObjectIterator::FromCurrentPage() {
while (cur_addr_ != cur_end_) {
HeapObject obj = HeapObject::FromAddress(cur_addr_);
const int obj_size = obj.Size();
cur_addr_ += obj_size;
DCHECK_LE(cur_addr_, cur_end_);
if (!obj.IsFreeSpaceOrFiller()) {
if (obj.IsCode()) {
DCHECK_EQ(space_->identity(), CODE_SPACE);
DCHECK_CODEOBJECT_SIZE(obj_size, space_);
} else {
DCHECK_OBJECT_SIZE(obj_size);
}
return obj;
}
}
return HeapObject();
}
bool PagedSpace::Contains(Address addr) const {
if (V8_ENABLE_THIRD_PARTY_HEAP_BOOL) {
return true;
}
return Page::FromAddress(addr)->owner() == this;
}
bool PagedSpace::Contains(Object o) const {
if (!o.IsHeapObject()) return false;
return Page::FromAddress(o.ptr())->owner() == this;
}
void PagedSpace::UnlinkFreeListCategories(Page* page) {
DCHECK_EQ(this, page->owner());
page->ForAllFreeListCategories([this](FreeListCategory* category) {
free_list()->RemoveCategory(category);
});
}
size_t PagedSpace::RelinkFreeListCategories(Page* page) {
DCHECK_EQ(this, page->owner());
size_t added = 0;
page->ForAllFreeListCategories([this, &added](FreeListCategory* category) {
added += category->available();
category->Relink(free_list());
});
DCHECK_IMPLIES(!page->IsFlagSet(Page::NEVER_ALLOCATE_ON_PAGE),
page->AvailableInFreeList() ==
page->AvailableInFreeListFromAllocatedBytes());
return added;
}
bool PagedSpace::TryFreeLast(HeapObject object, int object_size) {
if (allocation_info_.top() != kNullAddress) {
const Address object_address = object.address();
if ((allocation_info_.top() - object_size) == object_address) {
allocation_info_.set_top(object_address);
return true;
}
}
return false;
}
bool PagedSpace::EnsureLabMain(int size_in_bytes, AllocationOrigin origin) {
if (allocation_info_.top() + size_in_bytes <= allocation_info_.limit()) {
return true;
}
return RefillLabMain(size_in_bytes, origin);
}
AllocationResult PagedSpace::AllocateFastUnaligned(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 AllocationResult::Retry(identity());
DCHECK_LE(new_top, allocation_info_.limit());
allocation_info_.set_top(new_top);
return AllocationResult(HeapObject::FromAddress(current_top));
}
AllocationResult PagedSpace::AllocateFastAligned(
int size_in_bytes, int* aligned_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 AllocationResult::Retry(identity());
allocation_info_.set_top(new_top);
if (aligned_size_in_bytes)
*aligned_size_in_bytes = filler_size + size_in_bytes;
if (filler_size > 0) {
Heap::PrecedeWithFiller(ReadOnlyRoots(heap()),
HeapObject::FromAddress(current_top), filler_size);
}
return AllocationResult(HeapObject::FromAddress(current_top + filler_size));
}
AllocationResult PagedSpace::AllocateRawUnaligned(int size_in_bytes,
AllocationOrigin origin) {
DCHECK(!FLAG_enable_third_party_heap);
if (!EnsureLabMain(size_in_bytes, origin)) {
return AllocationResult::Retry(identity());
}
AllocationResult result = AllocateFastUnaligned(size_in_bytes);
DCHECK(!result.IsRetry());
MSAN_ALLOCATED_UNINITIALIZED_MEMORY(result.ToObjectChecked().address(),
size_in_bytes);
if (FLAG_trace_allocations_origins) {
UpdateAllocationOrigins(origin);
}
InvokeAllocationObservers(result.ToAddress(), size_in_bytes, size_in_bytes,
size_in_bytes);
return result;
}
AllocationResult PagedSpace::AllocateRawAligned(int size_in_bytes,
AllocationAlignment alignment,
AllocationOrigin origin) {
DCHECK(!FLAG_enable_third_party_heap);
DCHECK_EQ(identity(), OLD_SPACE);
int allocation_size = size_in_bytes;
// 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;
if (!EnsureLabMain(allocation_size, origin)) {
return AllocationResult::Retry(identity());
}
int aligned_size_in_bytes;
AllocationResult result =
AllocateFastAligned(size_in_bytes, &aligned_size_in_bytes, alignment);
DCHECK(!result.IsRetry());
MSAN_ALLOCATED_UNINITIALIZED_MEMORY(result.ToObjectChecked().address(),
size_in_bytes);
if (FLAG_trace_allocations_origins) {
UpdateAllocationOrigins(origin);
}
InvokeAllocationObservers(result.ToAddress(), size_in_bytes,
aligned_size_in_bytes, allocation_size);
return result;
}
AllocationResult PagedSpace::AllocateRaw(int size_in_bytes,
AllocationAlignment alignment,
AllocationOrigin origin) {
DCHECK(!FLAG_enable_third_party_heap);
AllocationResult result;
if (alignment != kWordAligned) {
result = AllocateFastAligned(size_in_bytes, nullptr, alignment);
} else {
result = AllocateFastUnaligned(size_in_bytes);
}
if (!result.IsRetry()) {
return result;
} else {
return AllocateRawSlow(size_in_bytes, alignment, origin);
}
}
} // namespace internal
} // namespace v8
#endif // V8_HEAP_PAGED_SPACES_INL_H_
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