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    return val;
}

#endif   /* XXH_FORCE_DIRECT_MEMORY_ACCESS */


/* ***   Endianness   *** */

/*!
 * @ingroup tuning
 * @def XXH_CPU_LITTLE_ENDIAN
 * @brief Whether the target is little endian.
 *
 * Defined to 1 if the target is little endian, or 0 if it is big endian.
 * It can be defined externally, for example on the compiler command line.
 *
 * If it is not defined,
 * a runtime check (which is usually constant folded) is used instead.
 *
 * @note
 *   This is not necessarily defined to an integer constant.
 *
 * @see XXH_isLittleEndian() for the runtime check.
 */
#ifndef XXH_CPU_LITTLE_ENDIAN
/*
 * Try to detect endianness automatically, to avoid the nonstandard behavior
 * in `XXH_isLittleEndian()`
 */
#  if defined(_WIN32) /* Windows is always little endian */ \
     || defined(__LITTLE_ENDIAN__) \
     || (defined(__BYTE_ORDER__) && __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__)
#    define XXH_CPU_LITTLE_ENDIAN 1
#  elif defined(__BIG_ENDIAN__) \
     || (defined(__BYTE_ORDER__) && __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__)
#    define XXH_CPU_LITTLE_ENDIAN 0
#  else
/*!
 * @internal
 * @brief Runtime check for @ref XXH_CPU_LITTLE_ENDIAN.
 *
 * Most compilers will constant fold this.
 */
static int XXH_isLittleEndian(void)
{
    /*
     * Portable and well-defined behavior.
     * Don't use static: it is detrimental to performance.
     */
    const union { xxh_u32 u; xxh_u8 c[4]; } one = { 1 };
    return one.c[0];
}
#   define XXH_CPU_LITTLE_ENDIAN   XXH_isLittleEndian()
#  endif
#endif




/* ****************************************
*  Compiler-specific Functions and Macros
******************************************/
#define XXH_GCC_VERSION (__GNUC__ * 100 + __GNUC_MINOR__)

#ifdef __has_builtin
#  define XXH_HAS_BUILTIN(x) __has_builtin(x)
#else
#  define XXH_HAS_BUILTIN(x) 0
#endif



/*
 * C23 and future versions have standard "unreachable()".
 * Once it has been implemented reliably we can add it as an
 * additional case:
 *
 * ```
 * #if defined(__STDC_VERSION__) && (__STDC_VERSION__ >= XXH_C23_VN)
 * #  include <stddef.h>
 * #  ifdef unreachable
 * #    define XXH_UNREACHABLE() unreachable()
 * #  endif
 * #endif
 * ```
 *
 * Note C++23 also has std::unreachable() which can be detected
 * as follows:
 * ```
 * #if defined(__cpp_lib_unreachable) && (__cpp_lib_unreachable >= 202202L)
 * #  include <utility>
 * #  define XXH_UNREACHABLE() std::unreachable()
 * #endif
 * ```
 * NB: `__cpp_lib_unreachable` is defined in the `<version>` header.
 * We don't use that as including `<utility>` in `extern "C"` blocks
 * doesn't work on GCC12
 */

#if XXH_HAS_BUILTIN(__builtin_unreachable)
#  define XXH_UNREACHABLE() __builtin_unreachable()

#elif defined(_MSC_VER)
#  define XXH_UNREACHABLE() __assume(0)

#else
#  define XXH_UNREACHABLE()
#endif

#if XXH_HAS_BUILTIN(__builtin_assume)
#  define XXH_ASSUME(c) __builtin_assume(c)
#else
#  define XXH_ASSUME(c) if (!(c)) { XXH_UNREACHABLE(); }
#endif

/*!
 * @internal
 * @def XXH_rotl32(x,r)
 * @brief 32-bit rotate left.
 *
 * @param x The 32-bit integer to be rotated.