/* * Copyright (c) 2016-2020, Yann Collet, Facebook, Inc. * All rights reserved. * * This source code is licensed under both the BSD-style license (found in the * LICENSE file in the root directory of this source tree) and the GPLv2 (found * in the COPYING file in the root directory of this source tree). * You may select, at your option, one of the above-listed licenses. */ #ifndef ZSTD_COMPILER_H #define ZSTD_COMPILER_H /*-******************************************************* * Compiler specifics *********************************************************/ /* force inlining */ #if !defined(ZSTD_NO_INLINE) #if (defined(__GNUC__) && !defined(__STRICT_ANSI__)) || defined(__cplusplus) || defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L /* C99 */ # define INLINE_KEYWORD inline #else # define INLINE_KEYWORD #endif #if defined(__GNUC__) || defined(__ICCARM__) # define FORCE_INLINE_ATTR __attribute__((always_inline)) #elif defined(_MSC_VER) # define FORCE_INLINE_ATTR __forceinline #else # define FORCE_INLINE_ATTR #endif #else #define INLINE_KEYWORD #define FORCE_INLINE_ATTR #endif /** On MSVC qsort requires that functions passed into it use the __cdecl calling conversion(CC). This explictly marks such functions as __cdecl so that the code will still compile if a CC other than __cdecl has been made the default. */ #if defined(_MSC_VER) # define WIN_CDECL __cdecl #else # define WIN_CDECL #endif /** * FORCE_INLINE_TEMPLATE is used to define C "templates", which take constant * parameters. They must be inlined for the compiler to eliminate the constant * branches. */ #define FORCE_INLINE_TEMPLATE static INLINE_KEYWORD FORCE_INLINE_ATTR /** * HINT_INLINE is used to help the compiler generate better code. It is *not* * used for "templates", so it can be tweaked based on the compilers * performance. * * gcc-4.8 and gcc-4.9 have been shown to benefit from leaving off the * always_inline attribute. * * clang up to 5.0.0 (trunk) benefit tremendously from the always_inline * attribute. */ #if !defined(__clang__) && defined(__GNUC__) && __GNUC__ >= 4 && __GNUC_MINOR__ >= 8 && __GNUC__ < 5 # define HINT_INLINE static INLINE_KEYWORD #else # define HINT_INLINE static INLINE_KEYWORD FORCE_INLINE_ATTR #endif /* UNUSED_ATTR tells the compiler it is okay if the function is unused. */ #if defined(__GNUC__) # define UNUSED_ATTR __attribute__((unused)) #else # define UNUSED_ATTR #endif /* force no inlining */ #ifdef _MSC_VER # define FORCE_NOINLINE static __declspec(noinline) #else # if defined(__GNUC__) || defined(__ICCARM__) # define FORCE_NOINLINE static __attribute__((__noinline__)) # else # define FORCE_NOINLINE static # endif #endif /* target attribute */ #ifndef __has_attribute #define __has_attribute(x) 0 /* Compatibility with non-clang compilers. */ #endif #if defined(__GNUC__) || defined(__ICCARM__) # define TARGET_ATTRIBUTE(target) __attribute__((__target__(target))) #else # define TARGET_ATTRIBUTE(target) #endif /* Enable runtime BMI2 dispatch based on the CPU. * Enabled for clang & gcc >=4.8 on x86 when BMI2 isn't enabled by default. */ #ifndef DYNAMIC_BMI2 #if ((defined(__clang__) && __has_attribute(__target__)) \ || (defined(__GNUC__) \ && (__GNUC__ >= 5 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 8)))) \ && (defined(__x86_64__) || defined(_M_X86)) \ && !defined(__BMI2__) # define DYNAMIC_BMI2 1 #else # define DYNAMIC_BMI2 0 #endif #endif /* prefetch * can be disabled, by declaring NO_PREFETCH build macro */ #if defined(NO_PREFETCH) # define PREFETCH_L1(ptr) (void)(ptr) /* disabled */ # define PREFETCH_L2(ptr) (void)(ptr) /* disabled */ #else # if defined(_MSC_VER) && (defined(_M_X64) || defined(_M_I86)) /* _mm_prefetch() is not defined outside of x86/x64 */ # include /* https://msdn.microsoft.com/fr-fr/library/84szxsww(v=vs.90).aspx */ # define PREFETCH_L1(ptr) _mm_prefetch((const char*)(ptr), _MM_HINT_T0) # define PREFETCH_L2(ptr) _mm_prefetch((const char*)(ptr), _MM_HINT_T1) # elif defined(__GNUC__) && ( (__GNUC__ >= 4) || ( (__GNUC__ == 3) && (__GNUC_MINOR__ >= 1) ) ) # define PREFETCH_L1(ptr) __builtin_prefetch((ptr), 0 /* rw==read */, 3 /* locality */) # define PREFETCH_L2(ptr) __builtin_prefetch((ptr), 0 /* rw==read */, 2 /* locality */) # elif defined(__aarch64__) # define PREFETCH_L1(ptr) __asm__ __volatile__("prfm pldl1keep, %0" ::"Q"(*(ptr))) # define PREFETCH_L2(ptr) __asm__ __volatile__("prfm pldl2keep, %0" ::"Q"(*(ptr))) # else # define PREFETCH_L1(ptr) (void)(ptr) /* disabled */ # define PREFETCH_L2(ptr) (void)(ptr) /* disabled */ # endif #endif /* NO_PREFETCH */ #define CACHELINE_SIZE 64 #define PREFETCH_AREA(p, s) { \ const char* const _ptr = (const char*)(p); \ size_t const _size = (size_t)(s); \ size_t _pos; \ for (_pos=0; _pos<_size; _pos+=CACHELINE_SIZE) { \ PREFETCH_L2(_ptr + _pos); \ } \ } /* vectorization * older GCC (pre gcc-4.3 picked as the cutoff) uses a different syntax */ #if !defined(__INTEL_COMPILER) && !defined(__clang__) && defined(__GNUC__) # if (__GNUC__ == 4 && __GNUC_MINOR__ > 3) || (__GNUC__ >= 5) # define DONT_VECTORIZE __attribute__((optimize("no-tree-vectorize"))) # else # define DONT_VECTORIZE _Pragma("GCC optimize(\"no-tree-vectorize\")") # endif #else # define DONT_VECTORIZE #endif /* Tell the compiler that a branch is likely or unlikely. * Only use these macros if it causes the compiler to generate better code. * If you can remove a LIKELY/UNLIKELY annotation without speed changes in gcc * and clang, please do. */ #if defined(__GNUC__) #define LIKELY(x) (__builtin_expect((x), 1)) #define UNLIKELY(x) (__builtin_expect((x), 0)) #else #define LIKELY(x) (x) #define UNLIKELY(x) (x) #endif /* disable warnings */ #ifdef _MSC_VER /* Visual Studio */ # include /* For Visual 2005 */ # pragma warning(disable : 4100) /* disable: C4100: unreferenced formal parameter */ # pragma warning(disable : 4127) /* disable: C4127: conditional expression is constant */ # pragma warning(disable : 4204) /* disable: C4204: non-constant aggregate initializer */ # pragma warning(disable : 4214) /* disable: C4214: non-int bitfields */ # pragma warning(disable : 4324) /* disable: C4324: padded structure */ #endif /*Like DYNAMIC_BMI2 but for compile time determination of BMI2 support*/ #ifndef STATIC_BMI2 # if defined(_MSC_VER) && (defined(_M_X64) || defined(_M_I86)) # ifdef __AVX2__ //MSVC does not have a BMI2 specific flag, but every CPU that supports AVX2 also supports BMI2 # define STATIC_BMI2 1 # endif # endif #endif #ifndef STATIC_BMI2 #define STATIC_BMI2 0 #endif #endif /* ZSTD_COMPILER_H */