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| author | Paul Eggert <eggert@cs.ucla.edu> | 2025-07-06 09:34:00 -0700 |
|---|---|---|
| committer | Paul Eggert <eggert@cs.ucla.edu> | 2025-07-09 17:12:40 -0700 |
| commit | 2ba421644138e43a8eb31513f8ea441696bc4b64 (patch) | |
| tree | c6930c9920e5606507706d997eed220c77034745 | |
| parent | factor: redo ge2 in terms of lt2 (diff) | |
| download | coreutils-2ba421644138e43a8eb31513f8ea441696bc4b64.tar.gz coreutils-2ba421644138e43a8eb31513f8ea441696bc4b64.zip | |
factor: Pollard-rho a is now mp_limb_t
* src/factor.c (factor_using_pollard_rho)
(factor_using_pollard_rho2): Use mp_limb_t, not unsigned long int,
for a parameter. This avoids some casts, and avoids a theoretical
bug where converting to mp_limb_t loses info.
| -rw-r--r-- | src/factor.c | 11 |
1 files changed, 5 insertions, 6 deletions
diff --git a/src/factor.c b/src/factor.c index 850e32a59..f7ddce0b8 100644 --- a/src/factor.c +++ b/src/factor.c @@ -1227,8 +1227,7 @@ mp_prime_p (mpz_t n) /* Insert into FACTORS the result of factoring N, using Pollard-rho with starting value A. N must be odd. */ static void -factor_using_pollard_rho (struct factors *factors, - mp_limb_t n, unsigned long int a) +factor_using_pollard_rho (struct factors *factors, mp_limb_t n, mp_limb_t a) { mp_limb_t x, z, y, P, t, ni, g; @@ -1314,7 +1313,7 @@ factor_using_pollard_rho (struct factors *factors, static void factor_using_pollard_rho2 (struct factors *factors, - mp_limb_t n1, mp_limb_t n0, unsigned long int a) + mp_limb_t n1, mp_limb_t n0, mp_limb_t a) { mp_limb_t x1, x0, z1, z0, y1, y0, P1, P0, t1, t0, g1, g0, r1m; @@ -1336,7 +1335,7 @@ factor_using_pollard_rho2 (struct factors *factors, { x0 = mulredc2 (&r1m, x1, x0, x1, x0, n1, n0, ni); x1 = r1m; - addmod2 (x1, x0, x1, x0, 0, (mp_limb_t) a, n1, n0); + addmod2 (x1, x0, x1, x0, 0, a, n1, n0); submod2 (t1, t0, z1, z0, x1, x0, n1, n0); P0 = mulredc2 (&r1m, P1, P0, t1, t0, n1, n0, ni); @@ -1359,7 +1358,7 @@ factor_using_pollard_rho2 (struct factors *factors, { x0 = mulredc2 (&r1m, x1, x0, x1, x0, n1, n0, ni); x1 = r1m; - addmod2 (x1, x0, x1, x0, 0, (mp_limb_t) a, n1, n0); + addmod2 (x1, x0, x1, x0, 0, a, n1, n0); } y1 = x1; y0 = x0; } @@ -1369,7 +1368,7 @@ factor_using_pollard_rho2 (struct factors *factors, { y0 = mulredc2 (&r1m, y1, y0, y1, y0, n1, n0, ni); y1 = r1m; - addmod2 (y1, y0, y1, y0, 0, (mp_limb_t) a, n1, n0); + addmod2 (y1, y0, y1, y0, 0, a, n1, n0); submod2 (t1, t0, z1, z0, y1, y0, n1, n0); uuset (&g1, &g0, gcd2_odd (t1, t0, n1, n0)); |