1 files changed, 123 insertions, 0 deletions
diff --git a/mpfr/tests/tget_d_2exp.c b/mpfr/tests/tget_d_2exp.c
new file mode 100644
index 000000000..2a7b42fcc
--- /dev/null
+++ b/mpfr/tests/tget_d_2exp.c
@@ -0,0 +1,123 @@
+/* Test mpfr_get_d_2exp.
+
+Copyright 1999, 2000, 2001, 2002, 2003 Free Software Foundation.
+
+This file is part of the MPFR Library.
+
+The MPFR Library is free software; you can redistribute it and/or modify
+it under the terms of the GNU Lesser General Public License as published by
+the Free Software Foundation; either version 2.1 of the License, or (at your
+option) any later version.
+
+The MPFR Library is distributed in the hope that it will be useful, but
+WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public
+License for more details.
+
+You should have received a copy of the GNU Lesser General Public License
+along with the MPFR Library; see the file COPYING.LIB.  If not, write to
+the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
+MA 02111-1307, USA. */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <float.h>
+#include "gmp.h"
+#include "gmp-impl.h"
+#include "mpfr.h"
+#include "mpfr-impl.h"
+#include "mpfr-test.h"
+
+
+/* Check that hardware rounding doesn't make mpfr_get_d_2exp return a value
+   outside its defined range. */
+static void
+check_round (void)
+{
+  static const unsigned long data[] = { 1, 32, 53, 54, 64, 128, 256, 512 };
+  mpfr_t  f;
+  double  got;
+  long    got_exp;
+  int     i, rnd_mode, neg;
+
+  mpfr_init2 (f, 1024L);
+
+  for (rnd_mode = 0; rnd_mode < 4; rnd_mode++)
+    {
+      for (i = 0; i < numberof (data); i++)
+        {
+          mpfr_set_ui (f, 1L, GMP_RNDZ);
+          mpfr_mul_2exp (f, f, data[i], GMP_RNDZ);
+          mpfr_sub_ui (f, f, 1L, GMP_RNDZ);
+
+          for (neg = 0; neg <= 1; neg++)
+            {
+              got = mpfr_get_d_2exp (&got_exp, f, rnd_mode);
+
+              if (neg == 0
+                  ? (got < 0.5 || got >= 1.0)
+                  : (got <= -1.0 || got > -0.5))
+                {
+                  printf  ("mpfr_get_d_2exp wrong on 2**%lu-1\n", data[i]);
+                  printf  ("result out of range, expect 0.5 <= got < 1.0\n");
+                  printf  ("   rnd_mode = %d\n", rnd_mode);
+                  printf  ("   data[i]  = %lu\n", data[i]);
+                  printf  ("   f    ");
+                  mpfr_out_str (stdout, 2, 0, f, GMP_RNDN);
+                  printf  ("\n");
+                  d_trace ("   got  ", got);
+                  printf  ("   got exp  %ld\n", got_exp);
+                  abort();
+                }
+
+              mpfr_neg (f, f, GMP_RNDZ);
+            }
+        }
+    }
+
+  mpfr_clear (f);
+}
+
+
+static void
+check_inf_nan ()
+{
+  /* only if nans and infs are available */
+#if _GMP_IEEE_FLOATS
+  mpfr_t  x;
+  double  d;
+  long    exp;
+
+  mpfr_init2 (x, 123);
+
+  mpfr_set_inf (x, 1);
+  d = mpfr_get_d_2exp (&exp, x, GMP_RNDZ);
+  ASSERT_ALWAYS (d > 0);
+  ASSERT_ALWAYS (DOUBLE_ISINF (d));
+
+  mpfr_set_inf (x, -1);
+  d = mpfr_get_d_2exp (&exp, x, GMP_RNDZ);
+  ASSERT_ALWAYS (d < 0);
+  ASSERT_ALWAYS (DOUBLE_ISINF (d));
+
+  mpfr_set_nan (x);
+  d = mpfr_get_d_2exp (&exp, x, GMP_RNDZ);
+  ASSERT_ALWAYS (DOUBLE_ISNAN (d));
+
+  mpfr_clear (x);
+#endif
+}
+
+
+int
+main (void)
+{
+  tests_start_mpfr ();
+  mpfr_test_init ();
+
+  check_round ();
+  check_inf_nan ();
+
+  tests_end_mpfr ();
+  return 0;
+}