Utilities/cmzstd/lib/common/compiler.h - third_party/cmake - Git at Google

 /*
  * Copyright (c) Meta Platforms, Inc. and affiliates.
  * 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

 #include "portability_macros.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 explicitly 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 */
 #if defined(__GNUC__) || defined(__ICCARM__)
 #  define TARGET_ATTRIBUTE(target) __attribute__((__target__(target)))
 #else
 #  define TARGET_ATTRIBUTE(target)
 #endif

 /* Target attribute for BMI2 dynamic dispatch.
  * Enable lzcnt, bmi, and bmi2.
  * We test for bmi1 & bmi2. lzcnt is included in bmi1.
  */
 #define BMI2_TARGET_ATTRIBUTE TARGET_ATTRIBUTE("lzcnt,bmi,bmi2")

 /* 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 <mmintrin.h>   /* 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,
  * and some compilers, like Intel ICC and MCST LCC, do not support it at all. */
 #if !defined(__INTEL_COMPILER) && !defined(__clang__) && defined(__GNUC__) && !defined(__LCC__)
 #  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

 #if __has_builtin(__builtin_unreachable) || (defined(__GNUC__) && (__GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 5)))
 #  define ZSTD_UNREACHABLE { assert(0), __builtin_unreachable(); }
 #else
 #  define ZSTD_UNREACHABLE { assert(0); }
 #endif

 /* disable warnings */
 #ifdef _MSC_VER    /* Visual Studio */
 #  include <intrin.h>                    /* 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
 #  elif defined(__BMI2__) && defined(__x86_64__) && defined(__GNUC__)
 #    define STATIC_BMI2 1
 #  endif
 #endif

 #ifndef STATIC_BMI2
     #define STATIC_BMI2 0
 #endif

 /* compile time determination of SIMD support */
 #if !defined(ZSTD_NO_INTRINSICS)
 #  if defined(__SSE2__) || defined(_M_AMD64) || (defined (_M_IX86) && defined(_M_IX86_FP) && (_M_IX86_FP >= 2))
 #    define ZSTD_ARCH_X86_SSE2
 #  endif
 #  if defined(__ARM_NEON) || defined(_M_ARM64)
 #    define ZSTD_ARCH_ARM_NEON
 #  endif
 #
 #  if defined(ZSTD_ARCH_X86_SSE2)
 #    include <emmintrin.h>
 #  elif defined(ZSTD_ARCH_ARM_NEON)
 #    include <arm_neon.h>
 #  endif
 #endif

 /* C-language Attributes are added in C23. */
 #if defined(__STDC_VERSION__) && (__STDC_VERSION__ > 201710L) && defined(__has_c_attribute)
 # define ZSTD_HAS_C_ATTRIBUTE(x) __has_c_attribute(x)
 #else
 # define ZSTD_HAS_C_ATTRIBUTE(x) 0
 #endif

 /* Only use C++ attributes in C++. Some compilers report support for C++
  * attributes when compiling with C.
  */
 #if defined(__cplusplus) && defined(__has_cpp_attribute)
 # define ZSTD_HAS_CPP_ATTRIBUTE(x) __has_cpp_attribute(x)
 #else
 # define ZSTD_HAS_CPP_ATTRIBUTE(x) 0
 #endif

 /* Define ZSTD_FALLTHROUGH macro for annotating switch case with the 'fallthrough' attribute.
  * - C23: https://en.cppreference.com/w/c/language/attributes/fallthrough
  * - CPP17: https://en.cppreference.com/w/cpp/language/attributes/fallthrough
  * - Else: __attribute__((__fallthrough__))
  */
 #ifndef ZSTD_FALLTHROUGH
 # if ZSTD_HAS_C_ATTRIBUTE(fallthrough)
 #  define ZSTD_FALLTHROUGH [[fallthrough]]
 # elif ZSTD_HAS_CPP_ATTRIBUTE(fallthrough)
 #  define ZSTD_FALLTHROUGH [[fallthrough]]
 # elif __has_attribute(__fallthrough__)
 /* Leading semicolon is to satisfy gcc-11 with -pedantic. Without the semicolon
  * gcc complains about: a label can only be part of a statement and a declaration is not a statement.
  */
 #  define ZSTD_FALLTHROUGH ; __attribute__((__fallthrough__))
 # else
 #  define ZSTD_FALLTHROUGH
 # endif
 #endif

 /*-**************************************************************
 *  Alignment check
 *****************************************************************/

 /* this test was initially positioned in mem.h,
  * but this file is removed (or replaced) for linux kernel
  * so it's now hosted in compiler.h,
  * which remains valid for both user & kernel spaces.
  */

 #ifndef ZSTD_ALIGNOF
 # if defined(__GNUC__) || defined(_MSC_VER)
 /* covers gcc, clang & MSVC */
 /* note : this section must come first, before C11,
  * due to a limitation in the kernel source generator */
 #  define ZSTD_ALIGNOF(T) __alignof(T)

 # elif defined(__SUNPRO_C) || defined(__SUNPRO_CC)
 /* Oracle Studio */
 #  define ZSTD_ALIGNOF(T) _Alignof(T)

 # elif defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 201112L)
 /* C11 support */
 #  include <stdalign.h>
 #  define ZSTD_ALIGNOF(T) alignof(T)

 # else
 /* No known support for alignof() - imperfect backup */
 #  define ZSTD_ALIGNOF(T) (sizeof(void*) < sizeof(T) ? sizeof(void*) : sizeof(T))

 # endif
 #endif /* ZSTD_ALIGNOF */

 /*-**************************************************************
 *  Sanitizer
 *****************************************************************/

 /* Issue #3240 reports an ASAN failure on an llvm-mingw build. Out of an
  * abundance of caution, disable our custom poisoning on mingw. */
 #ifdef __MINGW32__
 #ifndef ZSTD_ASAN_DONT_POISON_WORKSPACE
 #define ZSTD_ASAN_DONT_POISON_WORKSPACE 1
 #endif
 #ifndef ZSTD_MSAN_DONT_POISON_WORKSPACE
 #define ZSTD_MSAN_DONT_POISON_WORKSPACE 1
 #endif
 #endif

 #if ZSTD_MEMORY_SANITIZER && !defined(ZSTD_MSAN_DONT_POISON_WORKSPACE)
 /* Not all platforms that support msan provide sanitizers/msan_interface.h.
  * We therefore declare the functions we need ourselves, rather than trying to
  * include the header file... */
 #include <stddef.h>  /* size_t */
 #define ZSTD_DEPS_NEED_STDINT
 #include "zstd_deps.h"  /* intptr_t */

 /* Make memory region fully initialized (without changing its contents). */
 void __msan_unpoison(const volatile void *a, size_t size);

 /* Make memory region fully uninitialized (without changing its contents).
    This is a legacy interface that does not update origin information. Use
    __msan_allocated_memory() instead. */
 void __msan_poison(const volatile void *a, size_t size);

 /* Returns the offset of the first (at least partially) poisoned byte in the
    memory range, or -1 if the whole range is good. */
 intptr_t __msan_test_shadow(const volatile void *x, size_t size);

 /* Print shadow and origin for the memory range to stderr in a human-readable
    format. */
 void __msan_print_shadow(const volatile void *x, size_t size);
 #endif

 #if ZSTD_ADDRESS_SANITIZER && !defined(ZSTD_ASAN_DONT_POISON_WORKSPACE)
 /* Not all platforms that support asan provide sanitizers/asan_interface.h.
  * We therefore declare the functions we need ourselves, rather than trying to
  * include the header file... */
 #include <stddef.h>  /* size_t */

 /**
  * Marks a memory region (<c>[addr, addr+size)</c>) as unaddressable.
  *
  * This memory must be previously allocated by your program. Instrumented
  * code is forbidden from accessing addresses in this region until it is
  * unpoisoned. This function is not guaranteed to poison the entire region -
  * it could poison only a subregion of <c>[addr, addr+size)</c> due to ASan
  * alignment restrictions.
  *
  * \note This function is not thread-safe because no two threads can poison or
  * unpoison memory in the same memory region simultaneously.
  *
  * \param addr Start of memory region.
  * \param size Size of memory region. */
 void __asan_poison_memory_region(void const volatile *addr, size_t size);

 /**
  * Marks a memory region (<c>[addr, addr+size)</c>) as addressable.
  *
  * This memory must be previously allocated by your program. Accessing
  * addresses in this region is allowed until this region is poisoned again.
  * This function could unpoison a super-region of <c>[addr, addr+size)</c> due
  * to ASan alignment restrictions.
  *
  * \note This function is not thread-safe because no two threads can
  * poison or unpoison memory in the same memory region simultaneously.
  *
  * \param addr Start of memory region.
  * \param size Size of memory region. */
 void __asan_unpoison_memory_region(void const volatile *addr, size_t size);
 #endif

 #endif /* ZSTD_COMPILER_H */
	/*
	* Copyright (c) Meta Platforms, Inc. and affiliates.
	* 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

	#include "portability_macros.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 explicitly 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 */
	#if defined(__GNUC__) \|\| defined(__ICCARM__)
	# define TARGET_ATTRIBUTE(target) __attribute__((__target__(target)))
	#else
	# define TARGET_ATTRIBUTE(target)
	#endif

	/* Target attribute for BMI2 dynamic dispatch.
	* Enable lzcnt, bmi, and bmi2.
	* We test for bmi1 & bmi2. lzcnt is included in bmi1.
	*/
	#define BMI2_TARGET_ATTRIBUTE TARGET_ATTRIBUTE("lzcnt,bmi,bmi2")

	/* 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 <mmintrin.h> /* 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,
	* and some compilers, like Intel ICC and MCST LCC, do not support it at all. */
	#if !defined(__INTEL_COMPILER) && !defined(__clang__) && defined(__GNUC__) && !defined(__LCC__)
	# 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

	#if __has_builtin(__builtin_unreachable) \|\| (defined(__GNUC__) && (__GNUC__ > 4 \|\| (__GNUC__ == 4 && __GNUC_MINOR__ >= 5)))
	# define ZSTD_UNREACHABLE { assert(0), __builtin_unreachable(); }
	#else
	# define ZSTD_UNREACHABLE { assert(0); }
	#endif

	/* disable warnings */
	#ifdef _MSC_VER /* Visual Studio */
	# include <intrin.h> /* 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
	# elif defined(__BMI2__) && defined(__x86_64__) && defined(__GNUC__)
	# define STATIC_BMI2 1
	# endif
	#endif

	#ifndef STATIC_BMI2
	#define STATIC_BMI2 0
	#endif

	/* compile time determination of SIMD support */
	#if !defined(ZSTD_NO_INTRINSICS)
	# if defined(__SSE2__) \|\| defined(_M_AMD64) \|\| (defined (_M_IX86) && defined(_M_IX86_FP) && (_M_IX86_FP >= 2))
	# define ZSTD_ARCH_X86_SSE2
	# endif
	# if defined(__ARM_NEON) \|\| defined(_M_ARM64)
	# define ZSTD_ARCH_ARM_NEON
	# endif
	#
	# if defined(ZSTD_ARCH_X86_SSE2)
	# include <emmintrin.h>
	# elif defined(ZSTD_ARCH_ARM_NEON)
	# include <arm_neon.h>
	# endif
	#endif

	/* C-language Attributes are added in C23. */
	#if defined(__STDC_VERSION__) && (__STDC_VERSION__ > 201710L) && defined(__has_c_attribute)
	# define ZSTD_HAS_C_ATTRIBUTE(x) __has_c_attribute(x)
	#else
	# define ZSTD_HAS_C_ATTRIBUTE(x) 0
	#endif

	/* Only use C++ attributes in C++. Some compilers report support for C++
	* attributes when compiling with C.
	*/
	#if defined(__cplusplus) && defined(__has_cpp_attribute)
	# define ZSTD_HAS_CPP_ATTRIBUTE(x) __has_cpp_attribute(x)
	#else
	# define ZSTD_HAS_CPP_ATTRIBUTE(x) 0
	#endif

	/* Define ZSTD_FALLTHROUGH macro for annotating switch case with the 'fallthrough' attribute.
	* - C23: https://en.cppreference.com/w/c/language/attributes/fallthrough
	* - CPP17: https://en.cppreference.com/w/cpp/language/attributes/fallthrough
	* - Else: __attribute__((__fallthrough__))
	*/
	#ifndef ZSTD_FALLTHROUGH
	# if ZSTD_HAS_C_ATTRIBUTE(fallthrough)
	# define ZSTD_FALLTHROUGH [[fallthrough]]
	# elif ZSTD_HAS_CPP_ATTRIBUTE(fallthrough)
	# define ZSTD_FALLTHROUGH [[fallthrough]]
	# elif __has_attribute(__fallthrough__)
	/* Leading semicolon is to satisfy gcc-11 with -pedantic. Without the semicolon
	* gcc complains about: a label can only be part of a statement and a declaration is not a statement.
	*/
	# define ZSTD_FALLTHROUGH ; __attribute__((__fallthrough__))
	# else
	# define ZSTD_FALLTHROUGH
	# endif
	#endif

	/-*************************************************************
	* Alignment check
	*****************************************************************/

	/* this test was initially positioned in mem.h,
	* but this file is removed (or replaced) for linux kernel
	* so it's now hosted in compiler.h,
	* which remains valid for both user & kernel spaces.
	*/

	#ifndef ZSTD_ALIGNOF
	# if defined(__GNUC__) \|\| defined(_MSC_VER)
	/* covers gcc, clang & MSVC */
	/* note : this section must come first, before C11,
	* due to a limitation in the kernel source generator */
	# define ZSTD_ALIGNOF(T) __alignof(T)

	# elif defined(__SUNPRO_C) \|\| defined(__SUNPRO_CC)
	/* Oracle Studio */
	# define ZSTD_ALIGNOF(T) _Alignof(T)

	# elif defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 201112L)
	/* C11 support */
	# include <stdalign.h>
	# define ZSTD_ALIGNOF(T) alignof(T)

	# else
	/* No known support for alignof() - imperfect backup */
	# define ZSTD_ALIGNOF(T) (sizeof(void) < sizeof(T) ? sizeof(void) : sizeof(T))

	# endif
	#endif /* ZSTD_ALIGNOF */

	/-*************************************************************
	* Sanitizer
	*****************************************************************/

	/* Issue #3240 reports an ASAN failure on an llvm-mingw build. Out of an
	* abundance of caution, disable our custom poisoning on mingw. */
	#ifdef __MINGW32__
	#ifndef ZSTD_ASAN_DONT_POISON_WORKSPACE
	#define ZSTD_ASAN_DONT_POISON_WORKSPACE 1
	#endif
	#ifndef ZSTD_MSAN_DONT_POISON_WORKSPACE
	#define ZSTD_MSAN_DONT_POISON_WORKSPACE 1
	#endif
	#endif

	#if ZSTD_MEMORY_SANITIZER && !defined(ZSTD_MSAN_DONT_POISON_WORKSPACE)
	/* Not all platforms that support msan provide sanitizers/msan_interface.h.
	* We therefore declare the functions we need ourselves, rather than trying to
	* include the header file... */
	#include <stddef.h> /* size_t */
	#define ZSTD_DEPS_NEED_STDINT
	#include "zstd_deps.h" /* intptr_t */

	/* Make memory region fully initialized (without changing its contents). */
	void __msan_unpoison(const volatile void *a, size_t size);

	/* Make memory region fully uninitialized (without changing its contents).
	This is a legacy interface that does not update origin information. Use
	__msan_allocated_memory() instead. */
	void __msan_poison(const volatile void *a, size_t size);

	/* Returns the offset of the first (at least partially) poisoned byte in the
	memory range, or -1 if the whole range is good. */
	intptr_t __msan_test_shadow(const volatile void *x, size_t size);

	/* Print shadow and origin for the memory range to stderr in a human-readable
	format. */
	void __msan_print_shadow(const volatile void *x, size_t size);
	#endif

	#if ZSTD_ADDRESS_SANITIZER && !defined(ZSTD_ASAN_DONT_POISON_WORKSPACE)
	/* Not all platforms that support asan provide sanitizers/asan_interface.h.
	* We therefore declare the functions we need ourselves, rather than trying to
	* include the header file... */
	#include <stddef.h> /* size_t */

	/**
	* Marks a memory region (<c>[addr, addr+size)</c>) as unaddressable.
	*
	* This memory must be previously allocated by your program. Instrumented
	* code is forbidden from accessing addresses in this region until it is
	* unpoisoned. This function is not guaranteed to poison the entire region -
	* it could poison only a subregion of <c>[addr, addr+size)</c> due to ASan
	* alignment restrictions.
	*
	* \note This function is not thread-safe because no two threads can poison or
	* unpoison memory in the same memory region simultaneously.
	*
	* \param addr Start of memory region.
	* \param size Size of memory region. */
	void __asan_poison_memory_region(void const volatile *addr, size_t size);

	/**
	* Marks a memory region (<c>[addr, addr+size)</c>) as addressable.
	*
	* This memory must be previously allocated by your program. Accessing
	* addresses in this region is allowed until this region is poisoned again.
	* This function could unpoison a super-region of <c>[addr, addr+size)</c> due
	* to ASan alignment restrictions.
	*
	* \note This function is not thread-safe because no two threads can
	* poison or unpoison memory in the same memory region simultaneously.
	*
	* \param addr Start of memory region.
	* \param size Size of memory region. */
	void __asan_unpoison_memory_region(void const volatile *addr, size_t size);
	#endif

	#endif /* ZSTD_COMPILER_H */