private clock_t

time_clear(char *buf, int bsize, int nreps)

{

    clock_t t = clock();

    int i;

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

	memset(buf, 0, bsize);

    return clock() - t;

}

    section(f, "Cache sizes");

    /*

     * Determine the primary and secondary cache sizes by looking for a

     * non-linearity in the time required to fill blocks with memset.

     */

    {

#define MAX_BLOCK (1 << 20)

	static char buf[MAX_BLOCK];

	int bsize = 1 << 10;

	int nreps = 1;

	clock_t t = 0;

	clock_t t_eps;

	/*

	 * Increase the number of repetitions until the time is

	 * long enough to exceed the likely uncertainty.

	 */

	while ((t = time_clear(buf, bsize, nreps)) == 0)

	    nreps <<= 1;

	t_eps = t;

	while ((t = time_clear(buf, bsize, nreps)) < t_eps * 10)

	    nreps <<= 1;

	/*

	 * Increase the block size until the time jumps non-linearly.

	 */

	for (; bsize <= MAX_BLOCK;) {

	    clock_t dt = time_clear(buf, bsize, nreps);

	    if (dt > t + (t >> 1)) {

		t = dt;

		break;

	    }

	    bsize <<= 1;

	    nreps >>= 1;

	    if (nreps == 0)

		nreps = 1, t <<= 1;

	}

	define_int(f, "ARCH_CACHE1_SIZE", bsize >> 1);

	/*

	 * Do the same thing a second time for the secondary cache.

	 */

	if (nreps > 1)

	    nreps >>= 1, t >>= 1;

	for (; bsize <= MAX_BLOCK;) {

	    clock_t dt = time_clear(buf, bsize, nreps);

	    if (dt > t * 1.25) {

		t = dt;

		break;

	    }

	    bsize <<= 1;

	    nreps >>= 1;

	    if (nreps == 0)

		nreps = 1, t <<= 1;

	}

	define_int(f, "ARCH_CACHE2_SIZE", bsize >> 1);

    }

------ end of patches/patch-ac

------ begin patches/patch-ad