// Copyright 2022 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 INCLUDE_CPPGC_INTERNAL_CAGED_HEAP_H_ #define INCLUDE_CPPGC_INTERNAL_CAGED_HEAP_H_ #include #include #include "cppgc/internal/api-constants.h" #include "cppgc/internal/base-page-handle.h" #include "v8config.h" // NOLINT(build/include_directory) #if defined(CPPGC_CAGED_HEAP) namespace cppgc { namespace internal { class V8_EXPORT CagedHeapBase { public: V8_INLINE static uintptr_t OffsetFromAddress(const void* address) { return reinterpret_cast(address) & (api_constants::kCagedHeapReservationAlignment - 1); } V8_INLINE static bool IsWithinCage(const void* address) { CPPGC_DCHECK(g_heap_base_); return (reinterpret_cast(address) & ~(api_constants::kCagedHeapReservationAlignment - 1)) == g_heap_base_; } V8_INLINE static bool AreWithinCage(const void* addr1, const void* addr2) { #if defined(CPPGC_2GB_CAGE) static constexpr size_t kHalfWordShift = sizeof(uint32_t) * CHAR_BIT - 1; #else //! defined(CPPGC_2GB_CAGE) static constexpr size_t kHalfWordShift = sizeof(uint32_t) * CHAR_BIT; #endif //! defined(CPPGC_2GB_CAGE) static_assert((static_cast(1) << kHalfWordShift) == api_constants::kCagedHeapReservationSize); CPPGC_DCHECK(g_heap_base_); return !(((reinterpret_cast(addr1) ^ g_heap_base_) | (reinterpret_cast(addr2) ^ g_heap_base_)) >> kHalfWordShift); } V8_INLINE static uintptr_t GetBase() { return g_heap_base_; } private: friend class CagedHeap; static uintptr_t g_heap_base_; }; } // namespace internal } // namespace cppgc #endif // defined(CPPGC_CAGED_HEAP) #endif // INCLUDE_CPPGC_INTERNAL_CAGED_HEAP_H_