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// Copyright 2017 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_INVALIDATED_SLOTS_INL_H_
#define V8_HEAP_INVALIDATED_SLOTS_INL_H_
#include <map>
#include "src/heap/invalidated-slots.h"
#include "src/heap/spaces.h"
#include "src/objects/objects-body-descriptors-inl.h"
#include "src/objects/objects-body-descriptors.h"
#include "src/objects/objects.h"
#include "src/utils/allocation.h"
namespace v8 {
namespace internal {
bool InvalidatedSlotsFilter::IsValid(Address slot) {
#ifdef DEBUG
DCHECK_LT(slot, sentinel_);
// Slots must come in non-decreasing order.
DCHECK_LE(last_slot_, slot);
last_slot_ = slot;
#endif
while (slot >= invalidated_end_) {
++iterator_;
if (iterator_ != iterator_end_) {
// Invalidated ranges must not overlap.
DCHECK_LE(invalidated_end_, iterator_->first.address());
invalidated_start_ = iterator_->first.address();
invalidated_end_ = invalidated_start_ + iterator_->second;
invalidated_object_ = HeapObject();
invalidated_object_size_ = 0;
} else {
invalidated_start_ = sentinel_;
invalidated_end_ = sentinel_;
}
}
// Now the invalidated region ends after the slot.
if (slot < invalidated_start_) {
// The invalidated region starts after the slot.
return true;
}
// The invalidated region includes the slot.
// Ask the object if the slot is valid.
if (invalidated_object_.is_null()) {
invalidated_object_ = HeapObject::FromAddress(invalidated_start_);
DCHECK(!invalidated_object_.IsFiller());
invalidated_object_size_ =
invalidated_object_.SizeFromMap(invalidated_object_.map());
}
int offset = static_cast<int>(slot - invalidated_start_);
DCHECK_GT(offset, 0);
DCHECK_LE(invalidated_object_size_,
static_cast<int>(invalidated_end_ - invalidated_start_));
if (offset >= invalidated_object_size_) {
return slots_in_free_space_are_valid_;
}
return invalidated_object_.IsValidSlot(invalidated_object_.map(), offset);
}
void InvalidatedSlotsCleanup::Free(Address free_start, Address free_end) {
#ifdef DEBUG
DCHECK_LT(free_start, free_end);
// Free regions should come in increasing order and do not overlap
DCHECK_LE(last_free_, free_start);
last_free_ = free_start;
#endif
if (iterator_ == iterator_end_) return;
// Ignore invalidated objects before free region
while (free_start >= invalidated_end_) {
++iterator_;
NextInvalidatedObject();
}
// Loop here: Free region might contain multiple invalidated objects
while (free_end > invalidated_start_) {
// Case: Free region starts before current invalidated object
if (free_start <= invalidated_start_) {
iterator_ = invalidated_slots_->erase(iterator_);
} else {
// Case: Free region starts within current invalidated object
// (Can happen for right-trimmed objects)
iterator_++;
}
NextInvalidatedObject();
}
}
void InvalidatedSlotsCleanup::NextInvalidatedObject() {
if (iterator_ != iterator_end_) {
invalidated_start_ = iterator_->first.address();
invalidated_end_ = invalidated_start_ + iterator_->second;
} else {
invalidated_start_ = sentinel_;
invalidated_end_ = sentinel_;
}
}
} // namespace internal
} // namespace v8
#endif // V8_HEAP_INVALIDATED_SLOTS_INL_H_