factor: tweak comments

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

diff --git a/coreutils/factor.c b/coreutils/factor.c
index 66d6a7cae3dcb7819855dccdded515b677347e8e..7adc2385af9b7954d9e187b92896605923c450bb 100644 (file)
--- a/coreutils/factor.c
+++ b/coreutils/factor.c
@@ -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;