blob: 7a4d940891ca4b1bef842a04c95fafbe054a65d5 [file] [log] [blame]
// 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_COMMON_PTR_COMPR_INL_H_
#define V8_COMMON_PTR_COMPR_INL_H_
#include "include/v8-internal.h"
#include "src/common/ptr-compr.h"
#include "src/execution/isolate.h"
#include "src/execution/local-isolate-inl.h"
namespace v8 {
namespace internal {
#ifdef V8_COMPRESS_POINTERS
PtrComprCageBase::PtrComprCageBase(const Isolate* isolate)
: address_(isolate->cage_base()) {}
PtrComprCageBase::PtrComprCageBase(const LocalIsolate* isolate)
: address_(isolate->cage_base()) {}
Address PtrComprCageBase::address() const {
Address ret = address_;
ret = reinterpret_cast<Address>(V8_ASSUME_ALIGNED(
reinterpret_cast<void*>(ret), kPtrComprCageBaseAlignment));
return ret;
}
// Compresses full-pointer representation of a tagged value to on-heap
// representation.
V8_INLINE Tagged_t CompressTagged(Address tagged) {
return static_cast<Tagged_t>(static_cast<uint32_t>(tagged));
}
V8_INLINE constexpr Address GetPtrComprCageBaseAddress(Address on_heap_addr) {
return RoundDown<kPtrComprCageBaseAlignment>(on_heap_addr);
}
V8_INLINE Address GetPtrComprCageBaseAddress(PtrComprCageBase cage_base) {
return cage_base.address();
}
V8_INLINE constexpr PtrComprCageBase GetPtrComprCageBaseFromOnHeapAddress(
Address address) {
return PtrComprCageBase(GetPtrComprCageBaseAddress(address));
}
// Decompresses smi value.
V8_INLINE Address DecompressTaggedSigned(Tagged_t raw_value) {
// For runtime code the upper 32-bits of the Smi value do not matter.
return static_cast<Address>(raw_value);
}
// Decompresses weak or strong heap object pointer or forwarding pointer,
// preserving both weak- and smi- tags.
template <typename TOnHeapAddress>
V8_INLINE Address DecompressTaggedPointer(TOnHeapAddress on_heap_addr,
Tagged_t raw_value) {
return GetPtrComprCageBaseAddress(on_heap_addr) +
static_cast<Address>(raw_value);
}
// Decompresses any tagged value, preserving both weak- and smi- tags.
template <typename TOnHeapAddress>
V8_INLINE Address DecompressTaggedAny(TOnHeapAddress on_heap_addr,
Tagged_t raw_value) {
return DecompressTaggedPointer(on_heap_addr, raw_value);
}
STATIC_ASSERT(kPtrComprCageReservationSize ==
Internals::kPtrComprCageReservationSize);
STATIC_ASSERT(kPtrComprCageBaseAlignment ==
Internals::kPtrComprCageBaseAlignment);
#else
V8_INLINE Tagged_t CompressTagged(Address tagged) { UNREACHABLE(); }
V8_INLINE constexpr PtrComprCageBase GetPtrComprCageBaseFromOnHeapAddress(
Address address) {
return PtrComprCageBase();
}
V8_INLINE Address DecompressTaggedSigned(Tagged_t raw_value) { UNREACHABLE(); }
template <typename TOnHeapAddress>
V8_INLINE Address DecompressTaggedPointer(TOnHeapAddress on_heap_addr,
Tagged_t raw_value) {
UNREACHABLE();
}
template <typename TOnHeapAddress>
V8_INLINE Address DecompressTaggedAny(TOnHeapAddress on_heap_addr,
Tagged_t raw_value) {
UNREACHABLE();
}
#endif // V8_COMPRESS_POINTERS
inline PtrComprCageBase GetPtrComprCageBase(HeapObject object) {
return GetPtrComprCageBaseFromOnHeapAddress(object.ptr());
}
} // namespace internal
} // namespace v8
#endif // V8_COMMON_PTR_COMPR_INL_H_