[tests/tdiv.c] mpfr_div bug bug20180126: also test negative values.

(merged changeset r12137 from the trunk)

git-svn-id: svn://scm.gforge.inria.fr/svn/mpfr/branches/4.0@12138 280ebfd0-de03-0410-8827-d642c229c3f4

1 files changed, 32 insertions, 19 deletions

diff --git a/tests/tdiv.c b/tests/tdiv.c
index 092970131..4bd6748c3 100644
--- a/tests/tdiv.c
+++ b/tests/tdiv.c
@@ -1532,7 +1532,7 @@ static void
 bug20180126 (void)
 {
   mpfr_t a, b1, b2, c1, c2;
-  int pa, i, j, pc, r, inex1, inex2;
+  int pa, i, j, pc, sa, sb, r, inex1, inex2;
 
   for (pa = 100; pa < 800; pa += 11)
     for (i = 1; i <= 4; i++)
@@ -1557,30 +1557,43 @@ bug20180126 (void)
             {
               mpfr_inits2 (pc, c1, c2, (mpfr_ptr) 0);
 
-              RND_LOOP_NO_RNDF (r)
+              for (sa = 0; sa < 2; sa++)
                 {
-                  MPFR_ASSERTN (mpfr_equal_p (b1, b2));
-                  inex1 = mpfr_div (c1, a, b1, (mpfr_rnd_t) r);
-                  inex2 = mpfr_div (c2, a, b2, (mpfr_rnd_t) r);
-
-                  if (! mpfr_equal_p (c1, c2) || ! SAME_SIGN (inex1, inex2))
+                  for (sb = 0; sb < 2; sb++)
                     {
-                      printf ("Error in bug20180126 for "
-                              "pa=%d pb=%d pc=%d %s\n", pa, pb, pc,
-                              mpfr_print_rnd_mode ((mpfr_rnd_t) r));
-                      printf ("inex1 = %d, c1 = ", inex1);
-                      mpfr_dump (c1);
-                      printf ("inex2 = %d, c2 = ", inex2);
-                      mpfr_dump (c2);
-                      exit (1);
-                    }
-                }
+                      RND_LOOP_NO_RNDF (r)
+                        {
+                          MPFR_ASSERTN (mpfr_equal_p (b1, b2));
+                          inex1 = mpfr_div (c1, a, b1, (mpfr_rnd_t) r);
+                          inex2 = mpfr_div (c2, a, b2, (mpfr_rnd_t) r);
+
+                          if (! mpfr_equal_p (c1, c2) ||
+                              ! SAME_SIGN (inex1, inex2))
+                            {
+                              printf ("Error in bug20180126 for "
+                                      "pa=%d pb=%d pc=%d sa=%d sb=%d %s\n",
+                                      pa, pb, pc, sa, sb,
+                                      mpfr_print_rnd_mode ((mpfr_rnd_t) r));
+                              printf ("inex1 = %d, c1 = ", inex1);
+                              mpfr_dump (c1);
+                              printf ("inex2 = %d, c2 = ", inex2);
+                              mpfr_dump (c2);
+                              exit (1);
+                            }
+                        }
+
+                      mpfr_neg (b1, b1, MPFR_RNDN);
+                      mpfr_neg (b2, b2, MPFR_RNDN);
+                    }  /* sb */
+
+                  mpfr_neg (a, a, MPFR_RNDN);
+                }  /* sa */
 
               mpfr_clears (c1, c2, (mpfr_ptr) 0);
-            }
+            }  /* pc */
 
           mpfr_clears (a, b1, b2, (mpfr_ptr) 0);
-        }
+        }  /* j */
 }
 
 int