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    //! Byte swap intrinsics.
    #![allow(clippy::module_name_repetitions)]

    #[cfg(test)]
    use stdarch_test::assert_instr;

    /// Returns an integer with the reversed byte order of x
    ///
    /// [Intel's documentation](https://software.intel.com/sites/landingpage/IntrinsicsGuide/#text=_bswap)
    #[inline]
    #[cfg_attr(test, assert_instr(bswap))]
    #[stable(feature = "simd_x86", since = "1.27.0")]
    pub unsafe fn _bswap(x: i32) -> i32 {
        bswap_i32(x)
    }

    #[allow(improper_ctypes)]
    extern "C" {
        #[link_name = "llvm.bswap.i32"]
        fn bswap_i32(x: i32) -> i32;
    }

    #[cfg(test)]
    mod tests {
        use super::*;

        #[test]
        fn test_bswap() {
            unsafe {
                assert_eq!(_bswap(0x0EADBE0F), 0x0FBEAD0E);
                assert_eq!(_bswap(0x00000000), 0x00000000);
            }
        }
    }