1 // Copyright 2014 Google Inc. All Rights Reserved. 2 // 3 // Use of this source code is governed by a BSD-style license 4 // that can be found in the COPYING file in the root of the source 5 // tree. An additional intellectual property rights grant can be found 6 // in the file PATENTS. All contributing project authors may 7 // be found in the AUTHORS file in the root of the source tree. 8 // ----------------------------------------------------------------------------- 9 // 10 // Endian related functions. 11 12 #ifndef WEBP_UTILS_ENDIAN_INL_UTILS_H_ 13 #define WEBP_UTILS_ENDIAN_INL_UTILS_H_ 14 15 #ifdef HAVE_CONFIG_H 16 #include "src/webp/config.h" 17 #endif 18 19 #include "src/dsp/dsp.h" 20 #include "src/webp/types.h" 21 22 // some endian fix (e.g.: mips-gcc doesn't define __BIG_ENDIAN__) 23 #if !defined(WORDS_BIGENDIAN) && \ 24 (defined(__BIG_ENDIAN__) || defined(_M_PPC) || \ 25 (defined(__BYTE_ORDER__) && (__BYTE_ORDER__ == __ORDER_BIG_ENDIAN__))) 26 #define WORDS_BIGENDIAN 27 #endif 28 29 #if defined(WORDS_BIGENDIAN) 30 #define HToLE32 BSwap32 31 #define HToLE16 BSwap16 32 #else 33 #define HToLE32(x) (x) 34 #define HToLE16(x) (x) 35 #endif 36 37 #if !defined(HAVE_CONFIG_H) 38 #if LOCAL_GCC_PREREQ(4,8) || __has_builtin(__builtin_bswap16) 39 #define HAVE_BUILTIN_BSWAP16 40 #endif 41 #if LOCAL_GCC_PREREQ(4,3) || __has_builtin(__builtin_bswap32) 42 #define HAVE_BUILTIN_BSWAP32 43 #endif 44 #if LOCAL_GCC_PREREQ(4,3) || __has_builtin(__builtin_bswap64) 45 #define HAVE_BUILTIN_BSWAP64 46 #endif 47 #endif // !HAVE_CONFIG_H 48 49 static WEBP_INLINE uint16_t BSwap16(uint16_t x) { 50 #if defined(HAVE_BUILTIN_BSWAP16) 51 return __builtin_bswap16(x); 52 #elif defined(_MSC_VER) 53 return _byteswap_ushort(x); 54 #else 55 // gcc will recognize a 'rorw $8, ...' here: 56 return (x >> 8) | ((x & 0xff) << 8); 57 #endif // HAVE_BUILTIN_BSWAP16 58 } 59 60 static WEBP_INLINE uint32_t BSwap32(uint32_t x) { 61 #if defined(WEBP_USE_MIPS32_R2) 62 uint32_t ret; 63 __asm__ volatile ( 64 "wsbh %[ret], %[x] \n\t" 65 "rotr %[ret], %[ret], 16 \n\t" 66 : [ret]"=r"(ret) 67 : [x]"r"(x) 68 ); 69 return ret; 70 #elif defined(HAVE_BUILTIN_BSWAP32) 71 return __builtin_bswap32(x); 72 #elif defined(__i386__) || defined(__x86_64__) 73 uint32_t swapped_bytes; 74 __asm__ volatile("bswap %0" : "=r"(swapped_bytes) : "0"(x)); 75 return swapped_bytes; 76 #elif defined(_MSC_VER) 77 return (uint32_t)_byteswap_ulong(x); 78 #else 79 return (x >> 24) | ((x >> 8) & 0xff00) | ((x << 8) & 0xff0000) | (x << 24); 80 #endif // HAVE_BUILTIN_BSWAP32 81 } 82 83 static WEBP_INLINE uint64_t BSwap64(uint64_t x) { 84 #if defined(HAVE_BUILTIN_BSWAP64) 85 return __builtin_bswap64(x); 86 #elif defined(__x86_64__) 87 uint64_t swapped_bytes; 88 __asm__ volatile("bswapq %0" : "=r"(swapped_bytes) : "0"(x)); 89 return swapped_bytes; 90 #elif defined(_MSC_VER) 91 return (uint64_t)_byteswap_uint64(x); 92 #else // generic code for swapping 64-bit values (suggested by bdb@) 93 x = ((x & 0xffffffff00000000ull) >> 32) | ((x & 0x00000000ffffffffull) << 32); 94 x = ((x & 0xffff0000ffff0000ull) >> 16) | ((x & 0x0000ffff0000ffffull) << 16); 95 x = ((x & 0xff00ff00ff00ff00ull) >> 8) | ((x & 0x00ff00ff00ff00ffull) << 8); 96 return x; 97 #endif // HAVE_BUILTIN_BSWAP64 98 } 99 100 #endif // WEBP_UTILS_ENDIAN_INL_UTILS_H_ 101
