// 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 INCLUDE_CPPGC_INTERNAL_API_CONSTANTS_H_ #define INCLUDE_CPPGC_INTERNAL_API_CONSTANTS_H_ #include #include #include "v8config.h" // NOLINT(build/include_directory) namespace cppgc { namespace internal { // Embedders should not rely on this code! // Internal constants to avoid exposing internal types on the API surface. namespace api_constants { constexpr size_t kKB = 1024; constexpr size_t kMB = kKB * 1024; constexpr size_t kGB = kMB * 1024; // Offset of the uint16_t bitfield from the payload contaning the // in-construction bit. This is subtracted from the payload pointer to get // to the right bitfield. static constexpr size_t kFullyConstructedBitFieldOffsetFromPayload = 2 * sizeof(uint16_t); // Mask for in-construction bit. static constexpr uint16_t kFullyConstructedBitMask = uint16_t{1}; static constexpr size_t kPageSize = size_t{1} << 17; #if defined(V8_TARGET_ARCH_ARM64) && defined(V8_OS_DARWIN) constexpr size_t kGuardPageSize = 0; #else constexpr size_t kGuardPageSize = 4096; #endif static constexpr size_t kLargeObjectSizeThreshold = kPageSize / 2; #if defined(CPPGC_CAGED_HEAP) #if defined(CPPGC_2GB_CAGE) constexpr size_t kCagedHeapReservationSize = static_cast(2) * kGB; #else // !defined(CPPGC_2GB_CAGE) constexpr size_t kCagedHeapReservationSize = static_cast(4) * kGB; #endif // !defined(CPPGC_2GB_CAGE) constexpr size_t kCagedHeapReservationAlignment = kCagedHeapReservationSize; #endif // defined(CPPGC_CAGED_HEAP) static constexpr size_t kDefaultAlignment = sizeof(void*); // Maximum support alignment for a type as in `alignof(T)`. static constexpr size_t kMaxSupportedAlignment = 2 * kDefaultAlignment; // Granularity of heap allocations. constexpr size_t kAllocationGranularity = sizeof(void*); // Default cacheline size. constexpr size_t kCachelineSize = 64; } // namespace api_constants } // namespace internal } // namespace cppgc #endif // INCLUDE_CPPGC_INTERNAL_API_CONSTANTS_H_