crc.hh

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#ifndef __BASE_CRC_HH__
#define __BASE_CRC_HH__
 
#include "base/bitfield.hh"
 
namespace gem5
{
 
template <uint32_t Poly>
uint32_t
crc32(const uint8_t* data, uint32_t crc, std::size_t size)
{
    uint32_t byte = 0;
 
    crc = reverseBits(crc);
    for (auto i = 0; i < size; i++) {
        byte = data[i];
 
        // 32-bit reverse
        byte = reverseBits(byte);
        for (auto j = 0; j <= 7; j++) {
            if ((int)(crc ^ byte) < 0) {
                crc = (crc << 1) ^ Poly;
            } else {
                crc = crc << 1;
            }
            byte = byte << 1;
        }
    }
    return reverseBits(crc);
}
 
} // namespace gem5
 
#endif // __BASE_CRC_HH__