compiler-rt/lib/builtins/int_endianness.h

   1 //===-- int_endianness.h - configuration header for compiler-rt -----------===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8 //
   9 // This file is a configuration header for compiler-rt.
  10 // This file is not part of the interface of this library.
  11 //
  12 //===----------------------------------------------------------------------===//
  13
  14 #ifndef INT_ENDIANNESS_H
  15 #define INT_ENDIANNESS_H
  16
  17 #if defined(__BYTE_ORDER__) && defined(__ORDER_BIG_ENDIAN__) &&                \
  18     defined(__ORDER_LITTLE_ENDIAN__)
  19
  20 // Clang and GCC provide built-in endianness definitions.
  21 #if __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
  22 #define _YUGA_LITTLE_ENDIAN 0
  23 #define _YUGA_BIG_ENDIAN 1
  24 #elif __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
  25 #define _YUGA_LITTLE_ENDIAN 1
  26 #define _YUGA_BIG_ENDIAN 0
  27 #endif // __BYTE_ORDER__
  28
  29 #else // Compilers other than Clang or GCC.
  30
  31 #if defined(__SVR4) && defined(__sun)
  32 #include <sys/byteorder.h>
  33
  34 #if defined(_BIG_ENDIAN)
  35 #define _YUGA_LITTLE_ENDIAN 0
  36 #define _YUGA_BIG_ENDIAN 1
  37 #elif defined(_LITTLE_ENDIAN)
  38 #define _YUGA_LITTLE_ENDIAN 1
  39 #define _YUGA_BIG_ENDIAN 0
  40 #else // !_LITTLE_ENDIAN
  41 #error "unknown endianness"
  42 #endif // !_LITTLE_ENDIAN
  43
  44 #endif // Solaris
  45
  46 // ..
  47
  48 #if defined(__FreeBSD__) || defined(__NetBSD__) || defined(__DragonFly__) ||   \
  49     defined(__minix)
  50 #include <sys/endian.h>
  51
  52 #if _BYTE_ORDER == _BIG_ENDIAN
  53 #define _YUGA_LITTLE_ENDIAN 0
  54 #define _YUGA_BIG_ENDIAN 1
  55 #elif _BYTE_ORDER == _LITTLE_ENDIAN
  56 #define _YUGA_LITTLE_ENDIAN 1
  57 #define _YUGA_BIG_ENDIAN 0
  58 #endif // _BYTE_ORDER
  59
  60 #endif // *BSD
  61
  62 #if defined(__OpenBSD__)
  63 #include <machine/endian.h>
  64
  65 #if _BYTE_ORDER == _BIG_ENDIAN
  66 #define _YUGA_LITTLE_ENDIAN 0
  67 #define _YUGA_BIG_ENDIAN 1
  68 #elif _BYTE_ORDER == _LITTLE_ENDIAN
  69 #define _YUGA_LITTLE_ENDIAN 1
  70 #define _YUGA_BIG_ENDIAN 0
  71 #endif // _BYTE_ORDER
  72
  73 #endif // OpenBSD
  74
  75 // ..
  76
  77 // Mac OSX has __BIG_ENDIAN__ or __LITTLE_ENDIAN__ automatically set by the
  78 // compiler (at least with GCC)
  79 #if defined(__APPLE__) || defined(__ellcc__)
  80
  81 #ifdef __BIG_ENDIAN__
  82 #if __BIG_ENDIAN__
  83 #define _YUGA_LITTLE_ENDIAN 0
  84 #define _YUGA_BIG_ENDIAN 1
  85 #endif
  86 #endif // __BIG_ENDIAN__
  87
  88 #ifdef __LITTLE_ENDIAN__
  89 #if __LITTLE_ENDIAN__
  90 #define _YUGA_LITTLE_ENDIAN 1
  91 #define _YUGA_BIG_ENDIAN 0
  92 #endif
  93 #endif // __LITTLE_ENDIAN__
  94
  95 #endif // Mac OSX
  96
  97 // ..
  98
  99 #if defined(_WIN32)
 100
 101 #define _YUGA_LITTLE_ENDIAN 1
 102 #define _YUGA_BIG_ENDIAN 0
 103
 104 #endif // Windows
 105
 106 #endif // Clang or GCC.
 107
 108 // .
 109
 110 #if !defined(_YUGA_LITTLE_ENDIAN) || !defined(_YUGA_BIG_ENDIAN)
 111 #error Unable to determine endian
 112 #endif // Check we found an endianness correctly.
 113
 114 #endif // INT_ENDIANNESS_H