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      1 /* Copyright 2016 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 compiler / platform specific features and build options.
      8 
      9    Build options are:
     10     * BROTLI_BUILD_32_BIT disables 64-bit optimizations
     11     * BROTLI_BUILD_64_BIT forces to use 64-bit optimizations
     12     * BROTLI_BUILD_BIG_ENDIAN forces to use big-endian optimizations
     13     * BROTLI_BUILD_ENDIAN_NEUTRAL disables endian-aware optimizations
     14     * BROTLI_BUILD_LITTLE_ENDIAN forces to use little-endian optimizations
     15     * BROTLI_BUILD_PORTABLE disables dangerous optimizations, like unaligned
     16       read and overlapping memcpy; this reduces decompression speed by 5%
     17     * BROTLI_BUILD_NO_RBIT disables "rbit" optimization for ARM CPUs
     18     * BROTLI_DEBUG dumps file name and line number when decoder detects stream
     19       or memory error
     20     * BROTLI_ENABLE_LOG enables asserts and dumps various state information
     21 */
     22 
     23 #ifndef BROTLI_COMMON_PLATFORM_H_
     24 #define BROTLI_COMMON_PLATFORM_H_
     25 
     26 #include <string.h>  /* memcpy */
     27 #include <stdlib.h>  /* malloc, free */
     28 
     29 #include <brotli/port.h>
     30 #include <brotli/types.h>
     31 
     32 #if defined(OS_LINUX) || defined(OS_CYGWIN)
     33 #include <endian.h>
     34 #elif defined(OS_FREEBSD)
     35 #include <machine/endian.h>
     36 #elif defined(OS_MACOSX)
     37 #include <machine/endian.h>
     38 /* Let's try and follow the Linux convention */
     39 #define BROTLI_X_BYTE_ORDER BYTE_ORDER
     40 #define BROTLI_X_LITTLE_ENDIAN LITTLE_ENDIAN
     41 #define BROTLI_X_BIG_ENDIAN BIG_ENDIAN
     42 #endif
     43 
     44 #if defined(BROTLI_ENABLE_LOG) || defined(BROTLI_DEBUG)
     45 #include <assert.h>
     46 #include <stdio.h>
     47 #endif
     48 
     49 /* The following macros were borrowed from https://github.com/nemequ/hedley
     50  * with permission of original author - Evan Nemerson <evan (at) nemerson.com> */
     51 
     52 /* >>> >>> >>> hedley macros */
     53 
     54 /* Define "BROTLI_PREDICT_TRUE" and "BROTLI_PREDICT_FALSE" macros for capable
     55    compilers.
     56 
     57 To apply compiler hint, enclose the branching condition into macros, like this:
     58 
     59   if (BROTLI_PREDICT_TRUE(zero == 0)) {
     60     // main execution path
     61   } else {
     62     // compiler should place this code outside of main execution path
     63   }
     64 
     65 OR:
     66 
     67   if (BROTLI_PREDICT_FALSE(something_rare_or_unexpected_happens)) {
     68     // compiler should place this code outside of main execution path
     69   }
     70 
     71 */
     72 #if BROTLI_GNUC_HAS_BUILTIN(__builtin_expect, 3, 0, 0) || \
     73     BROTLI_INTEL_VERSION_CHECK(16, 0, 0) ||               \
     74     BROTLI_SUNPRO_VERSION_CHECK(5, 15, 0) ||              \
     75     BROTLI_ARM_VERSION_CHECK(4, 1, 0) ||                  \
     76     BROTLI_IBM_VERSION_CHECK(10, 1, 0) ||                 \
     77     BROTLI_TI_VERSION_CHECK(7, 3, 0) ||                   \
     78     BROTLI_TINYC_VERSION_CHECK(0, 9, 27)
     79 #define BROTLI_PREDICT_TRUE(x) (__builtin_expect(!!(x), 1))
     80 #define BROTLI_PREDICT_FALSE(x) (__builtin_expect(x, 0))
     81 #else
     82 #define BROTLI_PREDICT_FALSE(x) (x)
     83 #define BROTLI_PREDICT_TRUE(x) (x)
     84 #endif
     85 
     86 #if defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) && \
     87     !defined(__cplusplus)
     88 #define BROTLI_RESTRICT restrict
     89 #elif BROTLI_GNUC_VERSION_CHECK(3, 1, 0) ||                         \
     90     BROTLI_MSVC_VERSION_CHECK(14, 0, 0) ||                          \
     91     BROTLI_INTEL_VERSION_CHECK(16, 0, 0) ||                         \
     92     BROTLI_ARM_VERSION_CHECK(4, 1, 0) ||                            \
     93     BROTLI_IBM_VERSION_CHECK(10, 1, 0) ||                           \
     94     BROTLI_PGI_VERSION_CHECK(17, 10, 0) ||                          \
     95     BROTLI_TI_VERSION_CHECK(8, 0, 0) ||                             \
     96     BROTLI_IAR_VERSION_CHECK(8, 0, 0) ||                            \
     97     (BROTLI_SUNPRO_VERSION_CHECK(5, 14, 0) && defined(__cplusplus))
     98 #define BROTLI_RESTRICT __restrict
     99 #elif BROTLI_SUNPRO_VERSION_CHECK(5, 3, 0) && !defined(__cplusplus)
    100 #define BROTLI_RESTRICT _Restrict
    101 #else
    102 #define BROTLI_RESTRICT
    103 #endif
    104 
    105 #if (defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L)) || \
    106     (defined(__cplusplus) && (__cplusplus >= 199711L))
    107 #define BROTLI_MAYBE_INLINE inline
    108 #elif defined(__GNUC_STDC_INLINE__) || defined(__GNUC_GNU_INLINE__) || \
    109     BROTLI_ARM_VERSION_CHECK(6, 2, 0)
    110 #define BROTLI_MAYBE_INLINE __inline__
    111 #elif BROTLI_MSVC_VERSION_CHECK(12, 0, 0) || \
    112     BROTLI_ARM_VERSION_CHECK(4, 1, 0) || BROTLI_TI_VERSION_CHECK(8, 0, 0)
    113 #define BROTLI_MAYBE_INLINE __inline
    114 #else
    115 #define BROTLI_MAYBE_INLINE
    116 #endif
    117 
    118 #if BROTLI_GNUC_HAS_ATTRIBUTE(always_inline, 4, 0, 0) ||                       \
    119     BROTLI_INTEL_VERSION_CHECK(16, 0, 0) ||                                    \
    120     BROTLI_SUNPRO_VERSION_CHECK(5, 11, 0) ||                                   \
    121     BROTLI_ARM_VERSION_CHECK(4, 1, 0) ||                                       \
    122     BROTLI_IBM_VERSION_CHECK(10, 1, 0) ||                                      \
    123     BROTLI_TI_VERSION_CHECK(8, 0, 0) ||                                        \
    124     (BROTLI_TI_VERSION_CHECK(7, 3, 0) && defined(__TI_GNU_ATTRIBUTE_SUPPORT__))
    125 #define BROTLI_INLINE BROTLI_MAYBE_INLINE __attribute__((__always_inline__))
    126 #elif BROTLI_MSVC_VERSION_CHECK(12, 0, 0)
    127 #define BROTLI_INLINE BROTLI_MAYBE_INLINE __forceinline
    128 #elif BROTLI_TI_VERSION_CHECK(7, 0, 0) && defined(__cplusplus)
    129 #define BROTLI_INLINE BROTLI_MAYBE_INLINE _Pragma("FUNC_ALWAYS_INLINE;")
    130 #elif BROTLI_IAR_VERSION_CHECK(8, 0, 0)
    131 #define BROTLI_INLINE BROTLI_MAYBE_INLINE _Pragma("inline=forced")
    132 #else
    133 #define BROTLI_INLINE BROTLI_MAYBE_INLINE
    134 #endif
    135 
    136 #if BROTLI_GNUC_HAS_ATTRIBUTE(noinline, 4, 0, 0) ||                            \
    137     BROTLI_INTEL_VERSION_CHECK(16, 0, 0) ||                                    \
    138     BROTLI_SUNPRO_VERSION_CHECK(5, 11, 0) ||                                   \
    139     BROTLI_ARM_VERSION_CHECK(4, 1, 0) ||                                       \
    140     BROTLI_IBM_VERSION_CHECK(10, 1, 0) ||                                      \
    141     BROTLI_TI_VERSION_CHECK(8, 0, 0) ||                                        \
    142     (BROTLI_TI_VERSION_CHECK(7, 3, 0) && defined(__TI_GNU_ATTRIBUTE_SUPPORT__))
    143 #define BROTLI_NOINLINE __attribute__((__noinline__))
    144 #elif BROTLI_MSVC_VERSION_CHECK(13, 10, 0)
    145 #define BROTLI_NOINLINE __declspec(noinline)
    146 #elif BROTLI_PGI_VERSION_CHECK(10, 2, 0)
    147 #define BROTLI_NOINLINE _Pragma("noinline")
    148 #elif BROTLI_TI_VERSION_CHECK(6, 0, 0) && defined(__cplusplus)
    149 #define BROTLI_NOINLINE _Pragma("FUNC_CANNOT_INLINE;")
    150 #elif BROTLI_IAR_VERSION_CHECK(8, 0, 0)
    151 #define BROTLI_NOINLINE _Pragma("inline=never")
    152 #else
    153 #define BROTLI_NOINLINE
    154 #endif
    155 
    156 /* BROTLI_INTERNAL could be defined to override visibility, e.g. for tests. */
    157 #if !defined(BROTLI_INTERNAL)
    158 #if defined(_WIN32) || defined(__CYGWIN__)
    159 #define BROTLI_INTERNAL
    160 #elif BROTLI_GNUC_VERSION_CHECK(3, 3, 0) ||                         \
    161     BROTLI_TI_VERSION_CHECK(8, 0, 0) ||                             \
    162     BROTLI_INTEL_VERSION_CHECK(16, 0, 0) ||                         \
    163     BROTLI_ARM_VERSION_CHECK(4, 1, 0) ||                            \
    164     BROTLI_IBM_VERSION_CHECK(13, 1, 0) ||                           \
    165     BROTLI_SUNPRO_VERSION_CHECK(5, 11, 0) ||                        \
    166     (BROTLI_TI_VERSION_CHECK(7, 3, 0) &&                            \
    167      defined(__TI_GNU_ATTRIBUTE_SUPPORT__) && defined(__TI_EABI__))
    168 #define BROTLI_INTERNAL __attribute__ ((visibility ("hidden")))
    169 #else
    170 #define BROTLI_INTERNAL
    171 #endif
    172 #endif
    173 
    174 /* <<< <<< <<< end of hedley macros. */
    175 
    176 #if BROTLI_GNUC_HAS_ATTRIBUTE(unused, 2, 7, 0) || \
    177     BROTLI_INTEL_VERSION_CHECK(16, 0, 0)
    178 #define BROTLI_UNUSED_FUNCTION static BROTLI_INLINE __attribute__ ((unused))
    179 #else
    180 #define BROTLI_UNUSED_FUNCTION static BROTLI_INLINE
    181 #endif
    182 
    183 #if BROTLI_GNUC_HAS_ATTRIBUTE(aligned, 2, 7, 0)
    184 #define BROTLI_ALIGNED(N) __attribute__((aligned(N)))
    185 #else
    186 #define BROTLI_ALIGNED(N)
    187 #endif
    188 
    189 #if (defined(__ARM_ARCH) && (__ARM_ARCH == 7)) || \
    190     (defined(M_ARM) && (M_ARM == 7))
    191 #define BROTLI_TARGET_ARMV7
    192 #endif  /* ARMv7 */
    193 
    194 #if (defined(__ARM_ARCH) && (__ARM_ARCH == 8)) || \
    195     defined(__aarch64__) || defined(__ARM64_ARCH_8__)
    196 #define BROTLI_TARGET_ARMV8_ANY
    197 
    198 #if defined(__ARM_32BIT_STATE)
    199 #define BROTLI_TARGET_ARMV8_32
    200 #elif defined(__ARM_64BIT_STATE)
    201 #define BROTLI_TARGET_ARMV8_64
    202 #endif
    203 
    204 #endif  /* ARMv8 */
    205 
    206 #if defined(__ARM_NEON__) || defined(__ARM_NEON)
    207 #define BROTLI_TARGET_NEON
    208 #endif
    209 
    210 #if defined(__i386) || defined(_M_IX86)
    211 #define BROTLI_TARGET_X86
    212 #endif
    213 
    214 #if defined(__x86_64__) || defined(_M_X64)
    215 #define BROTLI_TARGET_X64
    216 #endif
    217 
    218 #if defined(__PPC64__)
    219 #define BROTLI_TARGET_POWERPC64
    220 #endif
    221 
    222 #if defined(__riscv) && defined(__riscv_xlen) && __riscv_xlen == 64
    223 #define BROTLI_TARGET_RISCV64
    224 #endif
    225 
    226 #if defined(BROTLI_BUILD_64_BIT)
    227 #define BROTLI_64_BITS 1
    228 #elif defined(BROTLI_BUILD_32_BIT)
    229 #define BROTLI_64_BITS 0
    230 #elif defined(BROTLI_TARGET_X64) || defined(BROTLI_TARGET_ARMV8_64) || \
    231     defined(BROTLI_TARGET_POWERPC64) || defined(BROTLI_TARGET_RISCV64)
    232 #define BROTLI_64_BITS 1
    233 #else
    234 #define BROTLI_64_BITS 0
    235 #endif
    236 
    237 #if (BROTLI_64_BITS)
    238 #define brotli_reg_t uint64_t
    239 #else
    240 #define brotli_reg_t uint32_t
    241 #endif
    242 
    243 #if defined(BROTLI_BUILD_BIG_ENDIAN)
    244 #define BROTLI_BIG_ENDIAN 1
    245 #elif defined(BROTLI_BUILD_LITTLE_ENDIAN)
    246 #define BROTLI_LITTLE_ENDIAN 1
    247 #elif defined(BROTLI_BUILD_ENDIAN_NEUTRAL)
    248 /* Just break elif chain. */
    249 #elif defined(__BYTE_ORDER__) && (__BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__)
    250 #define BROTLI_LITTLE_ENDIAN 1
    251 #elif defined(_WIN32) || defined(BROTLI_TARGET_X64)
    252 /* Win32 & x64 can currently always be assumed to be little endian */
    253 #define BROTLI_LITTLE_ENDIAN 1
    254 #elif defined(__BYTE_ORDER__) && (__BYTE_ORDER__ == __ORDER_BIG_ENDIAN__)
    255 #define BROTLI_BIG_ENDIAN 1
    256 #elif defined(BROTLI_X_BYTE_ORDER)
    257 #if BROTLI_X_BYTE_ORDER == BROTLI_X_LITTLE_ENDIAN
    258 #define BROTLI_LITTLE_ENDIAN 1
    259 #elif BROTLI_X_BYTE_ORDER == BROTLI_X_BIG_ENDIAN
    260 #define BROTLI_BIG_ENDIAN 1
    261 #endif
    262 #endif  /* BROTLI_X_BYTE_ORDER */
    263 
    264 #if !defined(BROTLI_LITTLE_ENDIAN)
    265 #define BROTLI_LITTLE_ENDIAN 0
    266 #endif
    267 
    268 #if !defined(BROTLI_BIG_ENDIAN)
    269 #define BROTLI_BIG_ENDIAN 0
    270 #endif
    271 
    272 #if defined(BROTLI_X_BYTE_ORDER)
    273 #undef BROTLI_X_BYTE_ORDER
    274 #undef BROTLI_X_LITTLE_ENDIAN
    275 #undef BROTLI_X_BIG_ENDIAN
    276 #endif
    277 
    278 #if defined(BROTLI_BUILD_PORTABLE)
    279 #define BROTLI_ALIGNED_READ (!!1)
    280 #elif defined(BROTLI_TARGET_X86) || defined(BROTLI_TARGET_X64) || \
    281     defined(BROTLI_TARGET_ARMV7) || defined(BROTLI_TARGET_ARMV8_ANY) || \
    282     defined(BROTLI_TARGET_RISCV64)
    283 /* Allow unaligned read only for white-listed CPUs. */
    284 #define BROTLI_ALIGNED_READ (!!0)
    285 #else
    286 #define BROTLI_ALIGNED_READ (!!1)
    287 #endif
    288 
    289 #if BROTLI_ALIGNED_READ
    290 /* Portable unaligned memory access: read / write values via memcpy. */
    291 static BROTLI_INLINE uint16_t BrotliUnalignedRead16(const void* p) {
    292   uint16_t t;
    293   memcpy(&t, p, sizeof t);
    294   return t;
    295 }
    296 static BROTLI_INLINE uint32_t BrotliUnalignedRead32(const void* p) {
    297   uint32_t t;
    298   memcpy(&t, p, sizeof t);
    299   return t;
    300 }
    301 static BROTLI_INLINE uint64_t BrotliUnalignedRead64(const void* p) {
    302   uint64_t t;
    303   memcpy(&t, p, sizeof t);
    304   return t;
    305 }
    306 static BROTLI_INLINE void BrotliUnalignedWrite64(void* p, uint64_t v) {
    307   memcpy(p, &v, sizeof v);
    308 }
    309 #else  /* BROTLI_ALIGNED_READ */
    310 /* Unaligned memory access is allowed: just cast pointer to requested type. */
    311 #if defined(ADDRESS_SANITIZER) || defined(THREAD_SANITIZER) || \
    312     defined(MEMORY_SANITIZER)
    313 /* Consider we have an unaligned load/store of 4 bytes from address 0x...05.
    314    AddressSanitizer will treat it as a 3-byte access to the range 05:07 and
    315    will miss a bug if 08 is the first unaddressable byte.
    316    ThreadSanitizer will also treat this as a 3-byte access to 05:07 and will
    317    miss a race between this access and some other accesses to 08.
    318    MemorySanitizer will correctly propagate the shadow on unaligned stores
    319    and correctly report bugs on unaligned loads, but it may not properly
    320    update and report the origin of the uninitialized memory.
    321    For all three tools, replacing an unaligned access with a tool-specific
    322    callback solves the problem. */
    323 #if defined(__cplusplus)
    324 extern "C" {
    325 #endif  /* __cplusplus */
    326   uint16_t __sanitizer_unaligned_load16(const void* p);
    327   uint32_t __sanitizer_unaligned_load32(const void* p);
    328   uint64_t __sanitizer_unaligned_load64(const void* p);
    329   void __sanitizer_unaligned_store64(void* p, uint64_t v);
    330 #if defined(__cplusplus)
    331 }  /* extern "C" */
    332 #endif  /* __cplusplus */
    333 #define BrotliUnalignedRead16 __sanitizer_unaligned_load16
    334 #define BrotliUnalignedRead32 __sanitizer_unaligned_load32
    335 #define BrotliUnalignedRead64 __sanitizer_unaligned_load64
    336 #define BrotliUnalignedWrite64 __sanitizer_unaligned_store64
    337 #else
    338 static BROTLI_INLINE uint16_t BrotliUnalignedRead16(const void* p) {
    339   return *(const uint16_t*)p;
    340 }
    341 static BROTLI_INLINE uint32_t BrotliUnalignedRead32(const void* p) {
    342   return *(const uint32_t*)p;
    343 }
    344 #if (BROTLI_64_BITS)
    345 static BROTLI_INLINE uint64_t BrotliUnalignedRead64(const void* p) {
    346   return *(const uint64_t*)p;
    347 }
    348 static BROTLI_INLINE void BrotliUnalignedWrite64(void* p, uint64_t v) {
    349   *(uint64_t*)p = v;
    350 }
    351 #else  /* BROTLI_64_BITS */
    352 /* Avoid emitting LDRD / STRD, which require properly aligned address. */
    353 /* If __attribute__(aligned) is available, use that. Otherwise, memcpy. */
    354 
    355 #if BROTLI_GNUC_HAS_ATTRIBUTE(aligned, 2, 7, 0)
    356 typedef BROTLI_ALIGNED(1) uint64_t brotli_unaligned_uint64_t;
    357 
    358 static BROTLI_INLINE uint64_t BrotliUnalignedRead64(const void* p) {
    359   return (uint64_t) ((brotli_unaligned_uint64_t*) p)[0];
    360 }
    361 static BROTLI_INLINE void BrotliUnalignedWrite64(void* p, uint64_t v) {
    362   brotli_unaligned_uint64_t* dwords = (brotli_unaligned_uint64_t*) p;
    363   dwords[0] = (brotli_unaligned_uint64_t) v;
    364 }
    365 #else /* BROTLI_GNUC_HAS_ATTRIBUTE(aligned, 2, 7, 0) */
    366 static BROTLI_INLINE uint64_t BrotliUnalignedRead64(const void* p) {
    367   uint64_t v;
    368   memcpy(&v, p, sizeof(uint64_t));
    369   return v;
    370 }
    371 
    372 static BROTLI_INLINE void BrotliUnalignedWrite64(void* p, uint64_t v) {
    373   memcpy(p, &v, sizeof(uint64_t));
    374 }
    375 #endif  /* BROTLI_GNUC_HAS_ATTRIBUTE(aligned, 2, 7, 0) */
    376 #endif  /* BROTLI_64_BITS */
    377 #endif  /* ASAN / TSAN / MSAN */
    378 #endif  /* BROTLI_ALIGNED_READ */
    379 
    380 #if BROTLI_LITTLE_ENDIAN
    381 /* Straight endianness. Just read / write values. */
    382 #define BROTLI_UNALIGNED_LOAD16LE BrotliUnalignedRead16
    383 #define BROTLI_UNALIGNED_LOAD32LE BrotliUnalignedRead32
    384 #define BROTLI_UNALIGNED_LOAD64LE BrotliUnalignedRead64
    385 #define BROTLI_UNALIGNED_STORE64LE BrotliUnalignedWrite64
    386 #elif BROTLI_BIG_ENDIAN  /* BROTLI_LITTLE_ENDIAN */
    387 /* Explain compiler to byte-swap values. */
    388 #define BROTLI_BSWAP16_(V) ((uint16_t)( \
    389   (((V) & 0xFFU) << 8) | \
    390   (((V) >> 8) & 0xFFU)))
    391 static BROTLI_INLINE uint16_t BROTLI_UNALIGNED_LOAD16LE(const void* p) {
    392   uint16_t value = BrotliUnalignedRead16(p);
    393   return BROTLI_BSWAP16_(value);
    394 }
    395 #define BROTLI_BSWAP32_(V) ( \
    396   (((V) & 0xFFU) << 24) | (((V) & 0xFF00U) << 8) | \
    397   (((V) >> 8) & 0xFF00U) | (((V) >> 24) & 0xFFU))
    398 static BROTLI_INLINE uint32_t BROTLI_UNALIGNED_LOAD32LE(const void* p) {
    399   uint32_t value = BrotliUnalignedRead32(p);
    400   return BROTLI_BSWAP32_(value);
    401 }
    402 #define BROTLI_BSWAP64_(V) ( \
    403   (((V) & 0xFFU) << 56) | (((V) & 0xFF00U) << 40) | \
    404   (((V) & 0xFF0000U) << 24) | (((V) & 0xFF000000U) << 8) | \
    405   (((V) >> 8) & 0xFF000000U) | (((V) >> 24) & 0xFF0000U) | \
    406   (((V) >> 40) & 0xFF00U) | (((V) >> 56) & 0xFFU))
    407 static BROTLI_INLINE uint64_t BROTLI_UNALIGNED_LOAD64LE(const void* p) {
    408   uint64_t value = BrotliUnalignedRead64(p);
    409   return BROTLI_BSWAP64_(value);
    410 }
    411 static BROTLI_INLINE void BROTLI_UNALIGNED_STORE64LE(void* p, uint64_t v) {
    412   uint64_t value = BROTLI_BSWAP64_(v);
    413   BrotliUnalignedWrite64(p, value);
    414 }
    415 #else  /* BROTLI_LITTLE_ENDIAN */
    416 /* Read / store values byte-wise; hopefully compiler will understand. */
    417 static BROTLI_INLINE uint16_t BROTLI_UNALIGNED_LOAD16LE(const void* p) {
    418   const uint8_t* in = (const uint8_t*)p;
    419   return (uint16_t)(in[0] | (in[1] << 8));
    420 }
    421 static BROTLI_INLINE uint32_t BROTLI_UNALIGNED_LOAD32LE(const void* p) {
    422   const uint8_t* in = (const uint8_t*)p;
    423   uint32_t value = (uint32_t)(in[0]);
    424   value |= (uint32_t)(in[1]) << 8;
    425   value |= (uint32_t)(in[2]) << 16;
    426   value |= (uint32_t)(in[3]) << 24;
    427   return value;
    428 }
    429 static BROTLI_INLINE uint64_t BROTLI_UNALIGNED_LOAD64LE(const void* p) {
    430   const uint8_t* in = (const uint8_t*)p;
    431   uint64_t value = (uint64_t)(in[0]);
    432   value |= (uint64_t)(in[1]) << 8;
    433   value |= (uint64_t)(in[2]) << 16;
    434   value |= (uint64_t)(in[3]) << 24;
    435   value |= (uint64_t)(in[4]) << 32;
    436   value |= (uint64_t)(in[5]) << 40;
    437   value |= (uint64_t)(in[6]) << 48;
    438   value |= (uint64_t)(in[7]) << 56;
    439   return value;
    440 }
    441 static BROTLI_INLINE void BROTLI_UNALIGNED_STORE64LE(void* p, uint64_t v) {
    442   uint8_t* out = (uint8_t*)p;
    443   out[0] = (uint8_t)v;
    444   out[1] = (uint8_t)(v >> 8);
    445   out[2] = (uint8_t)(v >> 16);
    446   out[3] = (uint8_t)(v >> 24);
    447   out[4] = (uint8_t)(v >> 32);
    448   out[5] = (uint8_t)(v >> 40);
    449   out[6] = (uint8_t)(v >> 48);
    450   out[7] = (uint8_t)(v >> 56);
    451 }
    452 #endif  /* BROTLI_LITTLE_ENDIAN */
    453 
    454 /* BROTLI_IS_CONSTANT macros returns true for compile-time constants. */
    455 #if BROTLI_GNUC_HAS_BUILTIN(__builtin_constant_p, 3, 0, 1) || \
    456     BROTLI_INTEL_VERSION_CHECK(16, 0, 0)
    457 #define BROTLI_IS_CONSTANT(x) (!!__builtin_constant_p(x))
    458 #else
    459 #define BROTLI_IS_CONSTANT(x) (!!0)
    460 #endif
    461 
    462 #if defined(BROTLI_TARGET_ARMV7) || defined(BROTLI_TARGET_ARMV8_ANY)
    463 #define BROTLI_HAS_UBFX (!!1)
    464 #else
    465 #define BROTLI_HAS_UBFX (!!0)
    466 #endif
    467 
    468 #if defined(BROTLI_ENABLE_LOG)
    469 #define BROTLI_DCHECK(x) assert(x)
    470 #define BROTLI_LOG(x) printf x
    471 #else
    472 #define BROTLI_DCHECK(x)
    473 #define BROTLI_LOG(x)
    474 #endif
    475 
    476 #if defined(BROTLI_DEBUG) || defined(BROTLI_ENABLE_LOG)
    477 static BROTLI_INLINE void BrotliDump(const char* f, int l, const char* fn) {
    478   fprintf(stderr, "%s:%d (%s)\n", f, l, fn);
    479   fflush(stderr);
    480 }
    481 #define BROTLI_DUMP() BrotliDump(__FILE__, __LINE__, __FUNCTION__)
    482 #else
    483 #define BROTLI_DUMP() (void)(0)
    484 #endif
    485 
    486 /* TODO: add appropriate icc/sunpro/arm/ibm/ti checks. */
    487 #if (BROTLI_GNUC_VERSION_CHECK(3, 0, 0) || defined(__llvm__)) && \
    488     !defined(BROTLI_BUILD_NO_RBIT)
    489 #if defined(BROTLI_TARGET_ARMV7) || defined(BROTLI_TARGET_ARMV8_ANY)
    490 /* TODO: detect ARMv6T2 and enable this code for it. */
    491 static BROTLI_INLINE brotli_reg_t BrotliRBit(brotli_reg_t input) {
    492   brotli_reg_t output;
    493   __asm__("rbit %0, %1\n" : "=r"(output) : "r"(input));
    494   return output;
    495 }
    496 #define BROTLI_RBIT(x) BrotliRBit(x)
    497 #endif  /* armv7 / armv8 */
    498 #endif  /* gcc || clang */
    499 #if !defined(BROTLI_RBIT)
    500 static BROTLI_INLINE void BrotliRBit(void) { /* Should break build if used. */ }
    501 #endif  /* BROTLI_RBIT */
    502 
    503 #define BROTLI_REPEAT(N, X) {     \
    504   if ((N & 1) != 0) {X;}          \
    505   if ((N & 2) != 0) {X; X;}       \
    506   if ((N & 4) != 0) {X; X; X; X;} \
    507 }
    508 
    509 #define BROTLI_UNUSED(X) (void)(X)
    510 
    511 #define BROTLI_MIN_MAX(T)                                                      \
    512   static BROTLI_INLINE T brotli_min_ ## T (T a, T b) { return a < b ? a : b; } \
    513   static BROTLI_INLINE T brotli_max_ ## T (T a, T b) { return a > b ? a : b; }
    514 BROTLI_MIN_MAX(double) BROTLI_MIN_MAX(float) BROTLI_MIN_MAX(int)
    515 BROTLI_MIN_MAX(size_t) BROTLI_MIN_MAX(uint32_t) BROTLI_MIN_MAX(uint8_t)
    516 #undef BROTLI_MIN_MAX
    517 #define BROTLI_MIN(T, A, B) (brotli_min_ ## T((A), (B)))
    518 #define BROTLI_MAX(T, A, B) (brotli_max_ ## T((A), (B)))
    519 
    520 #define BROTLI_SWAP(T, A, I, J) { \
    521   T __brotli_swap_tmp = (A)[(I)]; \
    522   (A)[(I)] = (A)[(J)];            \
    523   (A)[(J)] = __brotli_swap_tmp;   \
    524 }
    525 
    526 /* Default brotli_alloc_func */
    527 static void* BrotliDefaultAllocFunc(void* opaque, size_t size) {
    528   BROTLI_UNUSED(opaque);
    529   return malloc(size);
    530 }
    531 
    532 /* Default brotli_free_func */
    533 static void BrotliDefaultFreeFunc(void* opaque, void* address) {
    534   BROTLI_UNUSED(opaque);
    535   free(address);
    536 }
    537 
    538 BROTLI_UNUSED_FUNCTION void BrotliSuppressUnusedFunctions(void) {
    539   BROTLI_UNUSED(&BrotliSuppressUnusedFunctions);
    540   BROTLI_UNUSED(&BrotliUnalignedRead16);
    541   BROTLI_UNUSED(&BrotliUnalignedRead32);
    542   BROTLI_UNUSED(&BrotliUnalignedRead64);
    543   BROTLI_UNUSED(&BrotliUnalignedWrite64);
    544   BROTLI_UNUSED(&BROTLI_UNALIGNED_LOAD16LE);
    545   BROTLI_UNUSED(&BROTLI_UNALIGNED_LOAD32LE);
    546   BROTLI_UNUSED(&BROTLI_UNALIGNED_LOAD64LE);
    547   BROTLI_UNUSED(&BROTLI_UNALIGNED_STORE64LE);
    548   BROTLI_UNUSED(&BrotliRBit);
    549   BROTLI_UNUSED(&brotli_min_double);
    550   BROTLI_UNUSED(&brotli_max_double);
    551   BROTLI_UNUSED(&brotli_min_float);
    552   BROTLI_UNUSED(&brotli_max_float);
    553   BROTLI_UNUSED(&brotli_min_int);
    554   BROTLI_UNUSED(&brotli_max_int);
    555   BROTLI_UNUSED(&brotli_min_size_t);
    556   BROTLI_UNUSED(&brotli_max_size_t);
    557   BROTLI_UNUSED(&brotli_min_uint32_t);
    558   BROTLI_UNUSED(&brotli_max_uint32_t);
    559   BROTLI_UNUSED(&brotli_min_uint8_t);
    560   BROTLI_UNUSED(&brotli_max_uint8_t);
    561   BROTLI_UNUSED(&BrotliDefaultAllocFunc);
    562   BROTLI_UNUSED(&BrotliDefaultFreeFunc);
    563 #if defined(BROTLI_DEBUG) || defined(BROTLI_ENABLE_LOG)
    564   BROTLI_UNUSED(&BrotliDump);
    565 #endif
    566 }
    567 
    568 #endif  /* BROTLI_COMMON_PLATFORM_H_ */
    569