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Microsoft Specific

Emits the Streaming SIMD Extensions 4 (SSE4) instruction crc32. This instruction adds one parameter to the CRC-32C checksum of the other parameter.

unsigned int _mm_crc32_u8 (
   unsigned int crc,
   unsigned char v



[in] crc

An unsigned integer to add.

[in] v

A character. The checksum will be computed from this input parameter.

r := crc + CRC-32C(v)




x86, x64

Header file <nmmintrin.h>

CRC32-C algorithm is based on polynomial 0x1EDC6F41. It is implemented by following little-endian convention. This means that the most significant bit is treated as the least significant bit in the quotient.

Before using this intrinsic, software must ensure that the processor supports this instruction.

#include <stdio.h>
#include <nmmintrin.h>

int main ()
    unsigned int crc = 1;
    unsigned char input = 100;

    unsigned int res = _mm_crc32_u8(crc, input);
    printf_s("Result res: %u\n", res);

    return 0;
Result res: 1412925310