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The C and C++ Include Header Files

/usr/include/node/cppgc/internal/api-constants.h


$ cat -n /usr/include/node/cppgc/internal/api-constants.h

     1	// Copyright 2020 the V8 project authors. All rights reserved.
     2	// Use of this source code is governed by a BSD-style license that can be
     3	// found in the LICENSE file.
     4	
     5	#ifndef INCLUDE_CPPGC_INTERNAL_API_CONSTANTS_H_
     6	#define INCLUDE_CPPGC_INTERNAL_API_CONSTANTS_H_
     7	
     8	#include <cstddef>
     9	#include <cstdint>
    10	
    11	#include "v8config.h"  // NOLINT(build/include_directory)
    12	
    13	namespace cppgc {
    14	namespace internal {
    15	
    16	// Embedders should not rely on this code!
    17	
    18	// Internal constants to avoid exposing internal types on the API surface.
    19	namespace api_constants {
    20	
    21	constexpr size_t kKB = 1024;
    22	constexpr size_t kMB = kKB * 1024;
    23	constexpr size_t kGB = kMB * 1024;
    24	
    25	// Offset of the uint16_t bitfield from the payload contaning the
    26	// in-construction bit. This is subtracted from the payload pointer to get
    27	// to the right bitfield.
    28	static constexpr size_t kFullyConstructedBitFieldOffsetFromPayload =
    29	    2 * sizeof(uint16_t);
    30	// Mask for in-construction bit.
    31	static constexpr uint16_t kFullyConstructedBitMask = uint16_t{1};
    32	
    33	static constexpr size_t kPageSize = size_t{1} << 17;
    34	
    35	#if defined(V8_HOST_ARCH_ARM64) && defined(V8_OS_DARWIN)
    36	constexpr size_t kGuardPageSize = 0;
    37	#else
    38	constexpr size_t kGuardPageSize = 4096;
    39	#endif
    40	
    41	static constexpr size_t kLargeObjectSizeThreshold = kPageSize / 2;
    42	
    43	#if defined(CPPGC_POINTER_COMPRESSION)
    44	#if defined(CPPGC_ENABLE_LARGER_CAGE)
    45	constexpr unsigned kPointerCompressionShift = 3;
    46	#else   // !defined(CPPGC_ENABLE_LARGER_CAGE)
    47	constexpr unsigned kPointerCompressionShift = 1;
    48	#endif  // !defined(CPPGC_ENABLE_LARGER_CAGE)
    49	#endif  // !defined(CPPGC_POINTER_COMPRESSION)
    50	
    51	#if defined(CPPGC_CAGED_HEAP)
    52	#if defined(CPPGC_2GB_CAGE)
    53	constexpr size_t kCagedHeapDefaultReservationSize =
    54	    static_cast<size_t>(2) * kGB;
    55	constexpr size_t kCagedHeapMaxReservationSize =
    56	    kCagedHeapDefaultReservationSize;
    57	#else  // !defined(CPPGC_2GB_CAGE)
    58	constexpr size_t kCagedHeapDefaultReservationSize =
    59	    static_cast<size_t>(4) * kGB;
    60	#if defined(CPPGC_POINTER_COMPRESSION)
    61	constexpr size_t kCagedHeapMaxReservationSize =
    62	    size_t{1} << (31 + kPointerCompressionShift);
    63	#else   // !defined(CPPGC_POINTER_COMPRESSION)
    64	constexpr size_t kCagedHeapMaxReservationSize =
    65	    kCagedHeapDefaultReservationSize;
    66	#endif  // !defined(CPPGC_POINTER_COMPRESSION)
    67	#endif  // !defined(CPPGC_2GB_CAGE)
    68	constexpr size_t kCagedHeapReservationAlignment = kCagedHeapMaxReservationSize;
    69	#endif  // defined(CPPGC_CAGED_HEAP)
    70	
    71	static constexpr size_t kDefaultAlignment = sizeof(void*);
    72	
    73	// Maximum support alignment for a type as in `alignof(T)`.
    74	static constexpr size_t kMaxSupportedAlignment = 2 * kDefaultAlignment;
    75	
    76	// Granularity of heap allocations.
    77	constexpr size_t kAllocationGranularity = sizeof(void*);
    78	
    79	// Default cacheline size.
    80	constexpr size_t kCachelineSize = 64;
    81	
    82	}  // namespace api_constants
    83	
    84	}  // namespace internal
    85	}  // namespace cppgc
    86	
    87	#endif  // INCLUDE_CPPGC_INTERNAL_API_CONSTANTS_H_