Subversion Repositories hf-risc

#include <hf-risc.h>

/*

crc16 implementation:

width=16 poly=0x1021 init=0xffff refin=false refout=false xorout=0x0000 check=0x29b1 name="CRC-16/CCITT-FALSE"

*/

uint16_t crc16(uint8_t *data, uint32_t len){

        uint16_t crc = 0xffff, i;

        while(len--){

                crc ^= (uint16_t)*data++ << 8;

                for(i = 0; i < 8; ++i)

                        crc = crc << 1 ^ (crc & 0x8000 ? 0x1021 : 0x0000);

        }

        return crc;

}

/*

crc32 implementation:

width=32 poly=0x04c11db7 init=0xffffffff refin=false refout=false xorout=0x00000000 check=0x0376e6e7 name="CRC-32/MPEG-2"

*/

uint32_t crc32(uint8_t *data, uint32_t len){

        uint32_t crc = ~0, i;

        while(len--){

                crc ^= (uint32_t)*data++ << 24;

                for(i = 0; i < 8; ++i)

                        crc = crc << 1 ^ (crc & 0x80000000 ? 0x04c11db7 : 0x00000000);

        }

        return crc;

}

/*

crc64 implementation:

width=64 poly=0x42f0e1eba9ea3693 init=0x0000000000000000 refin=false refout=false xorout=0x0000000000000000 check=0x6c40df5f0b497347 name="CRC-64"

*/

uint64_t crc64(uint8_t *data, uint32_t len){

        uint64_t crc = 0;

        uint32_t i;

        while(len--){

                crc ^= (uint64_t)*data++ << 56;

                for(i = 0; i < 8; ++i)

                        crc = crc << 1 ^ (crc & 0x8000000000000000 ? 0x42f0e1eba9ea3693 : 0x0000000000000000);

        }

        return crc;

}

uint32_t xz_crc32_table[256];

void xz_crc32_init(void)

{

        const uint32_t poly = 0xEDB88320;

        uint32_t i;

        uint32_t j;

        uint32_t r;

        for (i = 0; i < 256; ++i) {

                r = i;

                for (j = 0; j < 8; ++j)

                        r = (r >> 1) ^ (poly & ~((r & 1) - 1));

                xz_crc32_table[i] = r;

        }

        return;

}

uint32_t xz_crc32(const uint8_t *buf, uint32_t size, uint32_t crc)

{

        crc = ~crc;

        while (size != 0) {

                crc = xz_crc32_table[*buf++ ^ (crc & 0xFF)] ^ (crc >> 8);

                --size;

        }

        return ~crc;

}

void main(void){

        uint8_t *str = "123456789";

        int32_t time;

        uint16_t crc1;

        uint32_t crc2, ops;

        uint64_t crc3;

        time = COUNTER;

        crc1 = crc16(str, strlen(str));

        time = COUNTER - time;

        printf("crc16: %8x, %d cycles\n", crc1, time);

        time = COUNTER;

        crc2 = crc32(str, strlen(str));

        time = COUNTER - time;

        printf("crc32: %8x, %d cycles\n", crc2, time);

        time = COUNTER;

        crc3 = crc64(str, strlen(str));

        time = COUNTER - time;

        printf("crc64: %8x%8x, %d cycles\n", (uint32_t)(crc3 >> 32), (uint32_t)(crc3 & 0xffffffff), time);

        xz_crc32_init();

        time = COUNTER;

        crc2 = xz_crc32(str, strlen(str), 0);

        time = COUNTER - time;

        printf("crc32 (table): %8x, %d cycles\n", crc2, time);

        return;

}