1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143
|
//===- endian.h - Endianness support ----------------------------*- C++ -*-===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// This file declares generic and optimized functions to swap the byte order of
// an integral type.
//
//===----------------------------------------------------------------------===//
#ifndef ORC_RT_ENDIAN_H
#define ORC_RT_ENDIAN_H
#include <cstddef>
#include <cstdint>
#include <type_traits>
#if defined(_MSC_VER) && !defined(_DEBUG)
#include <stdlib.h>
#endif
#if defined(__linux__) || defined(__GNU__) || defined(__HAIKU__) || \
defined(__Fuchsia__) || defined(__EMSCRIPTEN__)
#include <endian.h>
#elif defined(_AIX)
#include <sys/machine.h>
#elif defined(__sun)
/* Solaris provides _BIG_ENDIAN/_LITTLE_ENDIAN selector in sys/types.h */
#include <sys/types.h>
#define BIG_ENDIAN 4321
#define LITTLE_ENDIAN 1234
#if defined(_BIG_ENDIAN)
#define BYTE_ORDER BIG_ENDIAN
#else
#define BYTE_ORDER LITTLE_ENDIAN
#endif
#elif defined(__MVS__)
#define BIG_ENDIAN 4321
#define LITTLE_ENDIAN 1234
#define BYTE_ORDER BIG_ENDIAN
#else
#if !defined(BYTE_ORDER) && !defined(_WIN32)
#include <machine/endian.h>
#endif
#endif
namespace __orc_rt {
/// ByteSwap_16 - This function returns a byte-swapped representation of
/// the 16-bit argument.
inline uint16_t ByteSwap_16(uint16_t value) {
#if defined(_MSC_VER) && !defined(_DEBUG)
// The DLL version of the runtime lacks these functions (bug!?), but in a
// release build they're replaced with BSWAP instructions anyway.
return _byteswap_ushort(value);
#else
uint16_t Hi = value << 8;
uint16_t Lo = value >> 8;
return Hi | Lo;
#endif
}
/// This function returns a byte-swapped representation of the 32-bit argument.
inline uint32_t ByteSwap_32(uint32_t value) {
#if defined(__llvm__) || (defined(__GNUC__) && !defined(__ICC))
return __builtin_bswap32(value);
#elif defined(_MSC_VER) && !defined(_DEBUG)
return _byteswap_ulong(value);
#else
uint32_t Byte0 = value & 0x000000FF;
uint32_t Byte1 = value & 0x0000FF00;
uint32_t Byte2 = value & 0x00FF0000;
uint32_t Byte3 = value & 0xFF000000;
return (Byte0 << 24) | (Byte1 << 8) | (Byte2 >> 8) | (Byte3 >> 24);
#endif
}
/// This function returns a byte-swapped representation of the 64-bit argument.
inline uint64_t ByteSwap_64(uint64_t value) {
#if defined(__llvm__) || (defined(__GNUC__) && !defined(__ICC))
return __builtin_bswap64(value);
#elif defined(_MSC_VER) && !defined(_DEBUG)
return _byteswap_uint64(value);
#else
uint64_t Hi = ByteSwap_32(uint32_t(value));
uint32_t Lo = ByteSwap_32(uint32_t(value >> 32));
return (Hi << 32) | Lo;
#endif
}
#if defined(BYTE_ORDER) && defined(BIG_ENDIAN) && BYTE_ORDER == BIG_ENDIAN
constexpr bool IsBigEndianHost = true;
#else
constexpr bool IsBigEndianHost = false;
#endif
static const bool IsLittleEndianHost = !IsBigEndianHost;
inline unsigned char getSwappedBytes(unsigned char C) { return C; }
inline signed char getSwappedBytes(signed char C) { return C; }
inline char getSwappedBytes(char C) { return C; }
inline unsigned short getSwappedBytes(unsigned short C) {
return ByteSwap_16(C);
}
inline signed short getSwappedBytes(signed short C) { return ByteSwap_16(C); }
inline unsigned int getSwappedBytes(unsigned int C) { return ByteSwap_32(C); }
inline signed int getSwappedBytes(signed int C) { return ByteSwap_32(C); }
inline unsigned long getSwappedBytes(unsigned long C) {
// Handle LLP64 and LP64 platforms.
return sizeof(long) == sizeof(int) ? ByteSwap_32((uint32_t)C)
: ByteSwap_64((uint64_t)C);
}
inline signed long getSwappedBytes(signed long C) {
// Handle LLP64 and LP64 platforms.
return sizeof(long) == sizeof(int) ? ByteSwap_32((uint32_t)C)
: ByteSwap_64((uint64_t)C);
}
inline unsigned long long getSwappedBytes(unsigned long long C) {
return ByteSwap_64(C);
}
inline signed long long getSwappedBytes(signed long long C) {
return ByteSwap_64(C);
}
template <typename T>
inline std::enable_if_t<std::is_enum<T>::value, T> getSwappedBytes(T C) {
return static_cast<T>(
getSwappedBytes(static_cast<std::underlying_type_t<T>>(C)));
}
template <typename T> inline void swapByteOrder(T &Value) {
Value = getSwappedBytes(Value);
}
} // end namespace __orc_rt
#endif // ORC_RT_ENDIAN_H
|