[tests/tsum.c] New tests.

git-svn-id: svn://scm.gforge.inria.fr/svn/mpfr/branches/new-sum@9320 280ebfd0-de03-0410-8827-d642c229c3f4

1 files changed, 76 insertions, 0 deletions

diff --git a/tests/tsum.c b/tests/tsum.c
index c45efc3a7..14f12b47f 100644
--- a/tests/tsum.c
+++ b/tests/tsum.c
@@ -310,6 +310,81 @@ check_more_special (void)
   mpfr_clear (sum);
 }
 
+/* i * 2^46 + j * 2^45 + k * 2^44 + f * 2^(-2),
+   with -1 <= i, j, k <= 1, i != 0, -3 <= f <= 3,
+   ulp(exact sum) = 2^0 and ulp(exact sum) = 2^44. */
+static void
+check1 (void)
+{
+  mpfr_t sum1, sum2, s1, s2, s3, t[4];
+  mpfr_ptr p[4];
+  int i, j, k, f, prec, r, inex1, inex2;
+
+  mpfr_init2 (sum1, 47);
+  mpfr_init2 (sum2, 47);
+  mpfr_init2 (s1, 3);
+  mpfr_init2 (s2, 3);
+  mpfr_init2 (s3, 49);
+  for (i = 0; i < 4; i++)
+    {
+      mpfr_init2 (t[i], 2);
+      p[i] = t[i];
+    }
+
+  for (i = -1; i <= 1; i += 2)
+    {
+      mpfr_set_si_2exp (t[0], i, 46, MPFR_RNDN);
+      for (j = -1; j <= 1; j++)
+        {
+          mpfr_set_si_2exp (t[1], j, 45, MPFR_RNDN);
+          inex1 = mpfr_add (s1, t[0], t[1], MPFR_RNDN);
+          MPFR_ASSERTN (inex1 == 0);
+          for (k = -1; k <= 1; k++)
+            {
+              mpfr_set_si_2exp (t[2], k, 44, MPFR_RNDN);
+              inex1 = mpfr_add (s2, s1, t[2], MPFR_RNDN);
+              MPFR_ASSERTN (inex1 == 0);
+              for (f = -3; f <= 3; f++)
+                {
+                  mpfr_set_si_2exp (t[3], f, -2, MPFR_RNDN);
+                  inex1 = mpfr_add (s3, s2, t[3], MPFR_RNDN);
+                  MPFR_ASSERTN (inex1 == 0);
+                  for (prec = mpfr_get_exp (s3);
+                       prec >= MPFR_PREC_MIN;
+                       prec -= 44)
+                    {
+                      mpfr_set_prec (sum1, prec);
+                      mpfr_set_prec (sum2, prec);
+                      RND_LOOP (r)
+                        {
+                          inex1 = mpfr_set (sum1, s3, (mpfr_rnd_t) r);
+                          inex2 = mpfr_sum (sum2, p, 4, (mpfr_rnd_t) r);
+                          if (! mpfr_equal_p (sum1, sum2) || inex1 != inex2)
+                            {
+                              printf ("Error in check1 on %s, prec = %d, "
+                                      "i = %d, j = %d, k = %d, f = %d\n",
+                                      mpfr_print_rnd_mode ((mpfr_rnd_t) r),
+                                      prec, i, j, k, f);
+                              printf ("Expected ");
+                              mpfr_dump (sum1);
+                              printf ("with inex = %d\n", inex1);
+                              printf ("Got      ");
+                              mpfr_dump (sum2);
+                              printf ("with inex = %d\n", inex2);
+                              exit (1);
+                            }
+                        }
+                    }
+                }
+            }
+        }
+    }
+
+  for (i = 0; i < 4; i++)
+    mpfr_clear (t[i]);
+  mpfr_clears (sum1, sum2, s1, s2, s3, (mpfr_ptr) 0);
+}
+
 /* bug reported by Joseph S. Myers on 2013-10-27
    https://sympa.inria.fr/sympa/arc/mpfr/2013-10/msg00015.html */
 static void
@@ -489,6 +564,7 @@ main (void)
 
   check_special ();
   check_more_special ();
+  check1 ();
   bug20131027 ();
   generic_tests ();
   check_extreme ();