free-space-inl.h

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// Copyright 2018 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_OBJECTS_FREE_SPACE_INL_H_
#define V8_OBJECTS_FREE_SPACE_INL_H_
 
#include "src/objects/free-space.h"
// Include the non-inl header before the rest of the headers.
 
#include "src/execution/isolate.h"
#include "src/heap/heap-write-barrier-inl.h"
#include "src/heap/heap.h"
#include "src/objects/objects-inl.h"
 
// Has to be the last include (doesn't have include guards):
#include "src/objects/object-macros.h"
 
namespace v8 {
namespace internal {
 
#include "torque-generated/src/objects/free-space-tq-inl.inc"
 
TQ_OBJECT_CONSTRUCTORS_IMPL(FreeSpace)
 
RELAXED_SMI_ACCESSORS(FreeSpace, size, kSizeOffset)
 
// static
inline void FreeSpace::SetSize(const WritableFreeSpace& writable_free_space,
                               int size, RelaxedStoreTag tag) {
  writable_free_space.WriteHeaderSlot<Smi, kSizeOffset>(Smi::FromInt(size),
                                                        tag);
}
 
int FreeSpace::Size() { return size(kRelaxedLoad); }
 
Tagged<FreeSpace> FreeSpace::next() const {
  DCHECK(IsValid());
#ifdef V8_EXTERNAL_CODE_SPACE
  intptr_t diff_to_next =
      static_cast<intptr_t>(TaggedField<Smi, kNextOffset>::load(*this).value());
  if (diff_to_next == 0) {
    return FreeSpace();
  }
  Address next_ptr = ptr() + diff_to_next * kObjectAlignment;
  return UncheckedCast<FreeSpace>(Tagged<Object>(next_ptr));
#else
  return UncheckedCast<FreeSpace>(
      TaggedField<Object, kNextOffset>::load(*this));
#endif  // V8_EXTERNAL_CODE_SPACE
}
 
void FreeSpace::SetNext(const WritableFreeSpace& writable_free_space,
                        Tagged<FreeSpace> next) {
  DCHECK(IsValid());
 
#ifdef V8_EXTERNAL_CODE_SPACE
  if (next.is_null()) {
    writable_free_space.WriteHeaderSlot<Smi, kNextOffset>(Smi::zero(),
                                                          kRelaxedStore);
    return;
  }
  intptr_t diff_to_next = next.ptr() - ptr();
  DCHECK(IsAligned(diff_to_next, kObjectAlignment));
  writable_free_space.WriteHeaderSlot<Smi, kNextOffset>(
      Smi::FromIntptr(diff_to_next / kObjectAlignment), kRelaxedStore);
#else
  writable_free_space.WriteHeaderSlot<Object, kNextOffset>(next, kRelaxedStore);
#endif  // V8_EXTERNAL_CODE_SPACE
}
 
bool FreeSpace::IsValid() const { return Heap::IsFreeSpaceValid(*this); }
 
}  // namespace internal
}  // namespace v8
 
#include "src/objects/object-macros-undef.h"
 
#endif  // V8_OBJECTS_FREE_SPACE_INL_H_