test_xoroshi256ss.c

// XOROSHI256**

#include <stdio.h>
#include <stdint.h>

static inline uint64_t rotl(const uint64_t x, int k) {
	return (x << k) | (x >> (64 - k));
}

static uint64_t s[4];

uint64_t next(void) {
	const uint64_t result_starstar = rotl(s[1] * 5, 7) * 9;
	const uint64_t t = s[1] << 17;

	s[2] ^= s[0];
	s[3] ^= s[1];
	s[1] ^= s[2];
	s[0] ^= s[3];

	s[2] ^= t;

	s[3] = rotl(s[3], 45);

	return result_starstar;
}

int main(void)
{
  uint64_t l;

  s[0] = 0xdeadbeefdeadbeefLL;
  s[1] = 0xdeadbeefdeadbeefLL;
  s[2] = 0xdeadbeefdeadbeefLL;
  s[3] = 0xdeadbeefdeadbeefLL;

  // loop 1 billion times
  for (int i = 0; i < 1000000000; i++)
    l = next();

  fprintf(stdout, "%lu\n", l);
  return 0;
}