1 /* 2 * Copyright (c) 2016-2020, Yann Collet, Facebook, Inc. 3 * All rights reserved. 4 * 5 * This source code is licensed under both the BSD-style license (found in the 6 * LICENSE file in the root directory of this source tree) and the GPLv2 (found 7 * in the COPYING file in the root directory of this source tree). 8 * You may select, at your option, one of the above-listed licenses. 9 */ 10 11 #ifndef ZSTD_COMPILER_H 12 #define ZSTD_COMPILER_H 13 14 /*-******************************************************* 15 * Compiler specifics 16 *********************************************************/ 17 /* force inlining */ 18 19 #if !defined(ZSTD_NO_INLINE) 20 #if (defined(__GNUC__) && !defined(__STRICT_ANSI__)) || defined(__cplusplus) || defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L /* C99 */ 21 # define INLINE_KEYWORD inline 22 #else 23 # define INLINE_KEYWORD 24 #endif 25 26 #if defined(__GNUC__) || defined(__ICCARM__) 27 # define FORCE_INLINE_ATTR __attribute__((always_inline)) 28 #elif defined(_MSC_VER) 29 # define FORCE_INLINE_ATTR __forceinline 30 #else 31 # define FORCE_INLINE_ATTR 32 #endif 33 34 #else 35 36 #define INLINE_KEYWORD 37 #define FORCE_INLINE_ATTR 38 39 #endif 40 41 /** 42 On MSVC qsort requires that functions passed into it use the __cdecl calling conversion(CC). 43 This explictly marks such functions as __cdecl so that the code will still compile 44 if a CC other than __cdecl has been made the default. 45 */ 46 #if defined(_MSC_VER) 47 # define WIN_CDECL __cdecl 48 #else 49 # define WIN_CDECL 50 #endif 51 52 /** 53 * FORCE_INLINE_TEMPLATE is used to define C "templates", which take constant 54 * parameters. They must be inlined for the compiler to eliminate the constant 55 * branches. 56 */ 57 #define FORCE_INLINE_TEMPLATE static INLINE_KEYWORD FORCE_INLINE_ATTR 58 /** 59 * HINT_INLINE is used to help the compiler generate better code. It is *not* 60 * used for "templates", so it can be tweaked based on the compilers 61 * performance. 62 * 63 * gcc-4.8 and gcc-4.9 have been shown to benefit from leaving off the 64 * always_inline attribute. 65 * 66 * clang up to 5.0.0 (trunk) benefit tremendously from the always_inline 67 * attribute. 68 */ 69 #if !defined(__clang__) && defined(__GNUC__) && __GNUC__ >= 4 && __GNUC_MINOR__ >= 8 && __GNUC__ < 5 70 # define HINT_INLINE static INLINE_KEYWORD 71 #else 72 # define HINT_INLINE static INLINE_KEYWORD FORCE_INLINE_ATTR 73 #endif 74 75 /* UNUSED_ATTR tells the compiler it is okay if the function is unused. */ 76 #if defined(__GNUC__) 77 # define UNUSED_ATTR __attribute__((unused)) 78 #else 79 # define UNUSED_ATTR 80 #endif 81 82 /* force no inlining */ 83 #ifdef _MSC_VER 84 # define FORCE_NOINLINE static __declspec(noinline) 85 #else 86 # if defined(__GNUC__) || defined(__ICCARM__) 87 # define FORCE_NOINLINE static __attribute__((__noinline__)) 88 # else 89 # define FORCE_NOINLINE static 90 # endif 91 #endif 92 93 /* target attribute */ 94 #ifndef __has_attribute 95 #define __has_attribute(x) 0 /* Compatibility with non-clang compilers. */ 96 #endif 97 #if defined(__GNUC__) || defined(__ICCARM__) 98 # define TARGET_ATTRIBUTE(target) __attribute__((__target__(target))) 99 #else 100 # define TARGET_ATTRIBUTE(target) 101 #endif 102 103 /* Enable runtime BMI2 dispatch based on the CPU. 104 * Enabled for clang & gcc >=4.8 on x86 when BMI2 isn't enabled by default. 105 */ 106 #ifndef DYNAMIC_BMI2 107 #if ((defined(__clang__) && __has_attribute(__target__)) \ 108 || (defined(__GNUC__) \ 109 && (__GNUC__ >= 5 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 8)))) \ 110 && (defined(__x86_64__) || defined(_M_X86)) \ 111 && !defined(__BMI2__) 112 # define DYNAMIC_BMI2 1 113 #else 114 # define DYNAMIC_BMI2 0 115 #endif 116 #endif 117 118 /* prefetch 119 * can be disabled, by declaring NO_PREFETCH build macro */ 120 #if defined(NO_PREFETCH) 121 # define PREFETCH_L1(ptr) (void)(ptr) /* disabled */ 122 # define PREFETCH_L2(ptr) (void)(ptr) /* disabled */ 123 #else 124 # if defined(_MSC_VER) && (defined(_M_X64) || defined(_M_I86)) /* _mm_prefetch() is not defined outside of x86/x64 */ 125 # include <mmintrin.h> /* https://msdn.microsoft.com/fr-fr/library/84szxsww(v=vs.90).aspx */ 126 # define PREFETCH_L1(ptr) _mm_prefetch((const char*)(ptr), _MM_HINT_T0) 127 # define PREFETCH_L2(ptr) _mm_prefetch((const char*)(ptr), _MM_HINT_T1) 128 # elif defined(__GNUC__) && ( (__GNUC__ >= 4) || ( (__GNUC__ == 3) && (__GNUC_MINOR__ >= 1) ) ) 129 # define PREFETCH_L1(ptr) __builtin_prefetch((ptr), 0 /* rw==read */, 3 /* locality */) 130 # define PREFETCH_L2(ptr) __builtin_prefetch((ptr), 0 /* rw==read */, 2 /* locality */) 131 # elif defined(__aarch64__) 132 # define PREFETCH_L1(ptr) __asm__ __volatile__("prfm pldl1keep, %0" ::"Q"(*(ptr))) 133 # define PREFETCH_L2(ptr) __asm__ __volatile__("prfm pldl2keep, %0" ::"Q"(*(ptr))) 134 # else 135 # define PREFETCH_L1(ptr) (void)(ptr) /* disabled */ 136 # define PREFETCH_L2(ptr) (void)(ptr) /* disabled */ 137 # endif 138 #endif /* NO_PREFETCH */ 139 140 #define CACHELINE_SIZE 64 141 142 #define PREFETCH_AREA(p, s) { \ 143 const char* const _ptr = (const char*)(p); \ 144 size_t const _size = (size_t)(s); \ 145 size_t _pos; \ 146 for (_pos=0; _pos<_size; _pos+=CACHELINE_SIZE) { \ 147 PREFETCH_L2(_ptr + _pos); \ 148 } \ 149 } 150 151 /* vectorization 152 * older GCC (pre gcc-4.3 picked as the cutoff) uses a different syntax */ 153 #if !defined(__INTEL_COMPILER) && !defined(__clang__) && defined(__GNUC__) 154 # if (__GNUC__ == 4 && __GNUC_MINOR__ > 3) || (__GNUC__ >= 5) 155 # define DONT_VECTORIZE __attribute__((optimize("no-tree-vectorize"))) 156 # else 157 # define DONT_VECTORIZE _Pragma("GCC optimize(\"no-tree-vectorize\")") 158 # endif 159 #else 160 # define DONT_VECTORIZE 161 #endif 162 163 /* Tell the compiler that a branch is likely or unlikely. 164 * Only use these macros if it causes the compiler to generate better code. 165 * If you can remove a LIKELY/UNLIKELY annotation without speed changes in gcc 166 * and clang, please do. 167 */ 168 #if defined(__GNUC__) 169 #define LIKELY(x) (__builtin_expect((x), 1)) 170 #define UNLIKELY(x) (__builtin_expect((x), 0)) 171 #else 172 #define LIKELY(x) (x) 173 #define UNLIKELY(x) (x) 174 #endif 175 176 /* disable warnings */ 177 #ifdef _MSC_VER /* Visual Studio */ 178 # include <intrin.h> /* For Visual 2005 */ 179 # pragma warning(disable : 4100) /* disable: C4100: unreferenced formal parameter */ 180 # pragma warning(disable : 4127) /* disable: C4127: conditional expression is constant */ 181 # pragma warning(disable : 4204) /* disable: C4204: non-constant aggregate initializer */ 182 # pragma warning(disable : 4214) /* disable: C4214: non-int bitfields */ 183 # pragma warning(disable : 4324) /* disable: C4324: padded structure */ 184 #endif 185 186 /*Like DYNAMIC_BMI2 but for compile time determination of BMI2 support*/ 187 #ifndef STATIC_BMI2 188 # if defined(_MSC_VER) && (defined(_M_X64) || defined(_M_I86)) 189 # ifdef __AVX2__ //MSVC does not have a BMI2 specific flag, but every CPU that supports AVX2 also supports BMI2 190 # define STATIC_BMI2 1 191 # endif 192 # endif 193 #endif 194 195 #ifndef STATIC_BMI2 196 #define STATIC_BMI2 0 197 #endif 198 199 /* compat. with non-clang compilers */ 200 #ifndef __has_builtin 201 # define __has_builtin(x) 0 202 #endif 203 204 /* compat. with non-clang compilers */ 205 #ifndef __has_feature 206 # define __has_feature(x) 0 207 #endif 208 209 /* detects whether we are being compiled under msan */ 210 #ifndef ZSTD_MEMORY_SANITIZER 211 # if __has_feature(memory_sanitizer) 212 # define ZSTD_MEMORY_SANITIZER 1 213 # else 214 # define ZSTD_MEMORY_SANITIZER 0 215 # endif 216 #endif 217 218 #if ZSTD_MEMORY_SANITIZER 219 /* Not all platforms that support msan provide sanitizers/msan_interface.h. 220 * We therefore declare the functions we need ourselves, rather than trying to 221 * include the header file... */ 222 #include <stddef.h> /* size_t */ 223 #define ZSTD_DEPS_NEED_STDINT 224 #include "zstd_deps.h" /* intptr_t */ 225 226 /* Make memory region fully initialized (without changing its contents). */ 227 void __msan_unpoison(const volatile void *a, size_t size); 228 229 /* Make memory region fully uninitialized (without changing its contents). 230 This is a legacy interface that does not update origin information. Use 231 __msan_allocated_memory() instead. */ 232 void __msan_poison(const volatile void *a, size_t size); 233 234 /* Returns the offset of the first (at least partially) poisoned byte in the 235 memory range, or -1 if the whole range is good. */ 236 intptr_t __msan_test_shadow(const volatile void *x, size_t size); 237 #endif 238 239 /* detects whether we are being compiled under asan */ 240 #ifndef ZSTD_ADDRESS_SANITIZER 241 # if __has_feature(address_sanitizer) 242 # define ZSTD_ADDRESS_SANITIZER 1 243 # elif defined(__SANITIZE_ADDRESS__) 244 # define ZSTD_ADDRESS_SANITIZER 1 245 # else 246 # define ZSTD_ADDRESS_SANITIZER 0 247 # endif 248 #endif 249 250 #if ZSTD_ADDRESS_SANITIZER 251 /* Not all platforms that support asan provide sanitizers/asan_interface.h. 252 * We therefore declare the functions we need ourselves, rather than trying to 253 * include the header file... */ 254 #include <stddef.h> /* size_t */ 255 256 /** 257 * Marks a memory region (<c>[addr, addr+size)</c>) as unaddressable. 258 * 259 * This memory must be previously allocated by your program. Instrumented 260 * code is forbidden from accessing addresses in this region until it is 261 * unpoisoned. This function is not guaranteed to poison the entire region - 262 * it could poison only a subregion of <c>[addr, addr+size)</c> due to ASan 263 * alignment restrictions. 264 * 265 * \note This function is not thread-safe because no two threads can poison or 266 * unpoison memory in the same memory region simultaneously. 267 * 268 * \param addr Start of memory region. 269 * \param size Size of memory region. */ 270 void __asan_poison_memory_region(void const volatile *addr, size_t size); 271 272 /** 273 * Marks a memory region (<c>[addr, addr+size)</c>) as addressable. 274 * 275 * This memory must be previously allocated by your program. Accessing 276 * addresses in this region is allowed until this region is poisoned again. 277 * This function could unpoison a super-region of <c>[addr, addr+size)</c> due 278 * to ASan alignment restrictions. 279 * 280 * \note This function is not thread-safe because no two threads can 281 * poison or unpoison memory in the same memory region simultaneously. 282 * 283 * \param addr Start of memory region. 284 * \param size Size of memory region. */ 285 void __asan_unpoison_memory_region(void const volatile *addr, size_t size); 286 #endif 287 288 #endif /* ZSTD_COMPILER_H */ 289