crc.rs.html -- source
Description: Source to the Rust file `library/core/src/../../stdarch/crates/core_arch/src/aarch64/crc.rs`.
Keywords: rust, rustlang, rust-lang

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    extern "C" {
        #[link_name = "llvm.aarch64.crc32x"]
        fn crc32x_(crc: u32, data: u64) -> u32;

        #[link_name = "llvm.aarch64.crc32cx"]
        fn crc32cx_(crc: u32, data: u64) -> u32;
    }

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

    /// CRC32 single round checksum for quad words (64 bits).
    #[inline]
    #[target_feature(enable = "crc")]
    #[cfg_attr(test, assert_instr(crc32x))]
    pub unsafe fn __crc32d(crc: u32, data: u64) -> u32 {
        crc32x_(crc, data)
    }

    /// CRC32-C single round checksum for quad words (64 bits).
    #[inline]
    #[target_feature(enable = "crc")]
    #[cfg_attr(test, assert_instr(crc32cx))]
    pub unsafe fn __crc32cd(crc: u32, data: u64) -> u32 {
        crc32cx_(crc, data)
    }

    #[cfg(test)]
    mod tests {
        use crate::core_arch::{aarch64::*, simd::*};
        use std::mem;
        use stdarch_test::simd_test;

        #[simd_test(enable = "crc")]
        unsafe fn test_crc32d() {
            assert_eq!(__crc32d(0, 0), 0);
            assert_eq!(__crc32d(0, 18446744073709551615), 1147535477);
        }

        #[simd_test(enable = "crc")]
        unsafe fn test_crc32cd() {
            assert_eq!(__crc32cd(0, 0), 0);
            assert_eq!(__crc32cd(0, 18446744073709551615), 3293575501);
        }
    }