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#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <stdlib.h>
#include <stdio.h>
#define POLY_HI (1<<9)
#define POLY_LO ((1<<4)|(1<<0))
#define POLY (POLY_HI|POLY_LO)
#define POLY_REV ((1<<0)|(1<<5)|(1<<9))
#define POLY_MASK 0x1ff
extern __inline__ unsigned int hweight32(unsigned int w)
{
unsigned int res = (w & 0x55555555) + ((w >> 1) & 0x55555555);
res = (res & 0x33333333) + ((res >> 2) & 0x33333333);
res = (res & 0x0F0F0F0F) + ((res >> 4) & 0x0F0F0F0F);
res = (res & 0x00FF00FF) + ((res >> 8) & 0x00FF00FF);
return (res & 0x0000FFFF) + ((res >> 16) & 0x0000FFFF);
}
int main(int argc, char *argv[])
{
unsigned int divst, mulst = 0, cnt = 0;
divst = 1;
do {
divst <<= 1;
mulst <<= 1;
if (divst & POLY_HI) {
divst ^= POLY_LO;
mulst |= 1;
}
divst &= POLY_MASK;
cnt++;
printf("Count: %d State: %4d Out: %c Mul: %c Weight: %d\n", cnt, divst, '0'+(mulst & 1),
'0'+(hweight32(mulst & POLY_REV) & 1), hweight32(mulst & 0xfff));
} while (cnt < 10000 && divst != 1);
exit(0);
}
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