1 /* Copyright 2013 Google Inc. All Rights Reserved. 2 3 Distributed under MIT license. 4 See file LICENSE for detail or copy at https://opensource.org/licenses/MIT 5 */ 6 7 /* Macros for endianness, branch prediction and unaligned loads and stores. */ 8 9 #ifndef BROTLI_ENC_PORT_H_ 10 #define BROTLI_ENC_PORT_H_ 11 12 #include <assert.h> 13 #include <string.h> /* memcpy */ 14 15 #include <brotli/port.h> 16 #include <brotli/types.h> 17 18 #if defined OS_LINUX || defined OS_CYGWIN 19 #include <endian.h> 20 #elif defined OS_FREEBSD 21 #include <machine/endian.h> 22 #elif defined OS_MACOSX 23 #include <machine/endian.h> 24 /* Let's try and follow the Linux convention */ 25 #define __BYTE_ORDER BYTE_ORDER 26 #define __LITTLE_ENDIAN LITTLE_ENDIAN 27 #endif 28 29 /* define the macro IS_LITTLE_ENDIAN 30 using the above endian definitions from endian.h if 31 endian.h was included */ 32 #ifdef __BYTE_ORDER 33 #if __BYTE_ORDER == __LITTLE_ENDIAN 34 #define IS_LITTLE_ENDIAN 35 #endif 36 37 #else 38 39 #if defined(__LITTLE_ENDIAN__) 40 #define IS_LITTLE_ENDIAN 41 #endif 42 #endif /* __BYTE_ORDER */ 43 44 #if defined(__BYTE_ORDER__) && (__BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__) 45 #define IS_LITTLE_ENDIAN 46 #endif 47 48 /* Enable little-endian optimization for x64 architecture on Windows. */ 49 #if (defined(_WIN32) || defined(_WIN64)) && defined(_M_X64) 50 #define IS_LITTLE_ENDIAN 51 #endif 52 53 /* Portable handling of unaligned loads, stores, and copies. 54 On some platforms, like ARM, the copy functions can be more efficient 55 then a load and a store. */ 56 57 #if defined(ARCH_PIII) || \ 58 defined(ARCH_ATHLON) || defined(ARCH_K8) || defined(_ARCH_PPC) 59 60 /* x86 and x86-64 can perform unaligned loads/stores directly; 61 modern PowerPC hardware can also do unaligned integer loads and stores; 62 but note: the FPU still sends unaligned loads and stores to a trap handler! 63 */ 64 65 #define BROTLI_UNALIGNED_LOAD32(_p) (*(const uint32_t *)(_p)) 66 #define BROTLI_UNALIGNED_LOAD64(_p) (*(const uint64_t *)(_p)) 67 68 #define BROTLI_UNALIGNED_STORE32(_p, _val) \ 69 (*(uint32_t *)(_p) = (_val)) 70 #define BROTLI_UNALIGNED_STORE64(_p, _val) \ 71 (*(uint64_t *)(_p) = (_val)) 72 73 #elif defined(__arm__) && \ 74 !defined(__ARM_ARCH_5__) && \ 75 !defined(__ARM_ARCH_5T__) && \ 76 !defined(__ARM_ARCH_5TE__) && \ 77 !defined(__ARM_ARCH_5TEJ__) && \ 78 !defined(__ARM_ARCH_6__) && \ 79 !defined(__ARM_ARCH_6J__) && \ 80 !defined(__ARM_ARCH_6K__) && \ 81 !defined(__ARM_ARCH_6Z__) && \ 82 !defined(__ARM_ARCH_6ZK__) && \ 83 !defined(__ARM_ARCH_6T2__) 84 85 /* ARMv7 and newer support native unaligned accesses, but only of 16-bit 86 and 32-bit values (not 64-bit); older versions either raise a fatal signal, 87 do an unaligned read and rotate the words around a bit, or do the reads very 88 slowly (trip through kernel mode). */ 89 90 #define BROTLI_UNALIGNED_LOAD32(_p) (*(const uint32_t *)(_p)) 91 #define BROTLI_UNALIGNED_STORE32(_p, _val) \ 92 (*(uint32_t *)(_p) = (_val)) 93 94 static BROTLI_INLINE uint64_t BROTLI_UNALIGNED_LOAD64(const void *p) { 95 uint64_t t; 96 memcpy(&t, p, sizeof t); 97 return t; 98 } 99 100 static BROTLI_INLINE void BROTLI_UNALIGNED_STORE64(void *p, uint64_t v) { 101 memcpy(p, &v, sizeof v); 102 } 103 104 #else 105 106 /* These functions are provided for architectures that don't support */ 107 /* unaligned loads and stores. */ 108 109 static BROTLI_INLINE uint32_t BROTLI_UNALIGNED_LOAD32(const void *p) { 110 uint32_t t; 111 memcpy(&t, p, sizeof t); 112 return t; 113 } 114 115 static BROTLI_INLINE uint64_t BROTLI_UNALIGNED_LOAD64(const void *p) { 116 uint64_t t; 117 memcpy(&t, p, sizeof t); 118 return t; 119 } 120 121 static BROTLI_INLINE void BROTLI_UNALIGNED_STORE32(void *p, uint32_t v) { 122 memcpy(p, &v, sizeof v); 123 } 124 125 static BROTLI_INLINE void BROTLI_UNALIGNED_STORE64(void *p, uint64_t v) { 126 memcpy(p, &v, sizeof v); 127 } 128 129 #endif 130 131 #define TEMPLATE_(T) \ 132 static BROTLI_INLINE T brotli_min_ ## T (T a, T b) { return a < b ? a : b; } \ 133 static BROTLI_INLINE T brotli_max_ ## T (T a, T b) { return a > b ? a : b; } 134 TEMPLATE_(double) TEMPLATE_(float) TEMPLATE_(int) 135 TEMPLATE_(size_t) TEMPLATE_(uint32_t) TEMPLATE_(uint8_t) 136 #undef TEMPLATE_ 137 #define BROTLI_MIN(T, A, B) (brotli_min_ ## T((A), (B))) 138 #define BROTLI_MAX(T, A, B) (brotli_max_ ## T((A), (B))) 139 140 #define BROTLI_SWAP(T, A, I, J) { \ 141 T __brotli_swap_tmp = (A)[(I)]; \ 142 (A)[(I)] = (A)[(J)]; \ 143 (A)[(J)] = __brotli_swap_tmp; \ 144 } 145 146 #define BROTLI_ENSURE_CAPACITY(M, T, A, C, R) { \ 147 if (C < (R)) { \ 148 size_t _new_size = (C == 0) ? (R) : C; \ 149 T* new_array; \ 150 while (_new_size < (R)) _new_size *= 2; \ 151 new_array = BROTLI_ALLOC((M), T, _new_size); \ 152 if (!BROTLI_IS_OOM(m) && C != 0) \ 153 memcpy(new_array, A, C * sizeof(T)); \ 154 BROTLI_FREE((M), A); \ 155 A = new_array; \ 156 C = _new_size; \ 157 } \ 158 } 159 160 #endif /* BROTLI_ENC_PORT_H_ */ 161
