factor: tweak comments

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
This commit is contained in:
Denys Vlasenko 2017-04-13 10:51:13 +02:00
parent 6c149f4d9a
commit c054822027

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@ -58,7 +58,7 @@ static NOINLINE void factorize(wide_t N)
// unsigned count3;
// unsigned count5;
// unsigned count7;
// ^^^^^^^^^^^^^^^ commented-out simple siving code (easier to grasp).
// ^^^^^^^^^^^^^^^ commented-out simple sieving code (easier to grasp).
// Faster sieving, using one word for potentially up to 6 counters:
// count upwards in each mask, counter "triggers" when it sets its mask to "100[0]..."
// 10987654321098765432109876543210 - bits 31-0 in 32-bit word
@ -94,6 +94,8 @@ static NOINLINE void factorize(wide_t N)
* 18446744073709551601 = 53 348051774975651917
* the last factor requires testing up to
* 589959129 - about 100 million iterations.
* The slowest case (largest prime) for N < 2^64 is
* factor 18446744073709551557 (0xffffffffffffffc5).
*/
max_factor = isqrt_odd(N);
// count3 = 3;