Reverted non-bugfix improvements to mini-gmp, keep them for the next release.

1 files changed, 14 insertions, 11 deletions

diff --git a/mini-gmp/mini-gmp.c b/mini-gmp/mini-gmp.c
index e72655e2c..fff52c287 100644
--- a/mini-gmp/mini-gmp.c
+++ b/mini-gmp/mini-gmp.c
@@ -3184,26 +3184,29 @@ mpz_sqrt (mpz_t s, const mpz_t u)
 void
 mpz_fac_ui (mpz_t x, unsigned long n)
 {
-  mpz_set_ui (x, n + (n == 0));
-  for (;n > 2;)
-    mpz_mul_ui (x, x, --n);
+  if (n < 2) {
+    mpz_set_ui (x, 1);
+    return;
+  }
+  mpz_set_ui (x, n);
+  for (;--n > 1;)
+    mpz_mul_ui (x, x, n);
 }
 
 void
 mpz_bin_uiui (mpz_t r, unsigned long n, unsigned long k)
 {
   mpz_t t;
-  mpz_set_ui (r, k <= n);
-
-  if (k > (n >> 1))
-    k = (k <= n) ? n - k : 0;
 
+  if (k > n) {
+    r->_mp_size = 0;
+    return;
+  }
+  mpz_fac_ui (r, n);
   mpz_init (t);
   mpz_fac_ui (t, k);
-
-  for (; k > 0; k--)
-      mpz_mul_ui (r, r, n--);
-
+  mpz_divexact (r, r, t);
+  mpz_fac_ui (t, n - k);
   mpz_divexact (r, r, t);
   mpz_clear (t);
 }