Rewrite nails code.

1 files changed, 20 insertions, 2 deletions

diff --git a/mpz/tdiv_ui.c b/mpz/tdiv_ui.c
index 72858e930..406fbc4b2 100644
--- a/mpz/tdiv_ui.c
+++ b/mpz/tdiv_ui.c
@@ -29,11 +29,17 @@ mpz_tdiv_ui (mpz_srcptr dividend, unsigned long int divisor)
 {
   mp_size_t ns, nn;
   mp_ptr np;
+  mp_limb_t rl;
 
   if (divisor == 0)
     DIVIDE_BY_ZERO;
 
   ns = SIZ(dividend);
+  if (ns == 0)
+    {
+      return 0;
+    }
+
   nn = ABS(ns);
   np = PTR(dividend);
 
@@ -42,17 +48,29 @@ mpz_tdiv_ui (mpz_srcptr dividend, unsigned long int divisor)
     {
       mp_limb_t dp[2], rp[2];
       mp_ptr qp;
+      mp_size_t rn;
       TMP_DECL (mark);
 
+      if (nn == 1)		/* tdiv_qr requirements; tested above for 0 */
+	{
+	  rl = np[0];
+	  return rl;
+	}
+
       TMP_MARK (mark);
       dp[0] = divisor & GMP_NUMB_MASK;
       dp[1] = divisor >> GMP_NUMB_BITS;
       qp = TMP_ALLOC_LIMBS (nn - 2 + 1);
       mpn_tdiv_qr (qp, rp, (mp_size_t) 0, np, nn, dp, (mp_size_t) 2);
       TMP_FREE (mark);
-      return rp[0] + (rp[1] << GMP_NUMB_BITS);
+      rl = rp[0] + (rp[1] << GMP_NUMB_BITS);
+      rn = 2 - (rp[1] == 0);  rn -= (rp[rn - 1] == 0);
     }
+  else
 #endif
+    {
+      rl = mpn_mod_1 (np, nn, (mp_limb_t) divisor);
+    }
 
-  return mpn_mod_1 (np, nn, (mp_limb_t) divisor);
+  return rl;
 }