[tests] Added always_scale argument (boolean) to tests_default_random()

so that when it is true, scaling is always performed on random numbers
generated by mpfr_urandomb(), instead of preferring numbers of the order
of magnitude of 1 for half outputs. This will be useful for mpfr_rint_*
tests.

For tgeneric.c, the value of this argument is controlled by a new macro
TEST_RANDOM_ALWAYS_SCALE (0 by default, which corresponds to the current
behavior). For the other tests that call tests_default_random(), the
argument is set to 0, so that the behavior remains the same.

git-svn-id: svn://scm.gforge.inria.fr/svn/mpfr/trunk@9471 280ebfd0-de03-0410-8827-d642c229c3f4

7 files changed, 20 insertions, 10 deletions

diff --git a/tests/mpfr-test.h b/tests/mpfr-test.h
index 102911019..6e39b7a28 100644
--- a/tests/mpfr-test.h
+++ b/tests/mpfr-test.h
@@ -97,7 +97,8 @@ void ld_trace _MPFR_PROTO ((const char *, long double));
 FILE *src_fopen _MPFR_PROTO ((const char *, const char *));
 void set_emin _MPFR_PROTO ((mpfr_exp_t));
 void set_emax _MPFR_PROTO ((mpfr_exp_t));
-void tests_default_random _MPFR_PROTO ((mpfr_ptr, int, mpfr_exp_t, mpfr_exp_t));
+void tests_default_random _MPFR_PROTO ((mpfr_ptr, int, mpfr_exp_t, mpfr_exp_t,
+                                        int));
 void data_check _MPFR_PROTO ((const char *, int (*) (FLIST), const char *));
 void bad_cases _MPFR_PROTO ((int (*)(FLIST), int (*)(FLIST),
                              const char *, int, mpfr_exp_t, mpfr_exp_t,
diff --git a/tests/tests.c b/tests/tests.c
index f869fe476..18e7ad0d1 100644
--- a/tests/tests.c
+++ b/tests/tests.c
@@ -589,7 +589,8 @@ set_emax (mpfr_exp_t exponent)
    If pos=0, all generated numbers are positive.
 */
 void
-tests_default_random (mpfr_ptr x, int pos, mpfr_exp_t emin, mpfr_exp_t emax)
+tests_default_random (mpfr_ptr x, int pos, mpfr_exp_t emin, mpfr_exp_t emax,
+                      int always_scale)
 {
   MPFR_ASSERTN (emin <= emax);
   MPFR_ASSERTN (emin >= MPFR_EMIN_MIN);
@@ -600,7 +601,7 @@ tests_default_random (mpfr_ptr x, int pos, mpfr_exp_t emin, mpfr_exp_t emax)
      exponent range (well, this is a bit ugly...). */
 
   mpfr_urandomb (x, RANDS);
-  if (MPFR_IS_PURE_FP (x) && (emin >= 1 || (randlimb () & 1)))
+  if (MPFR_IS_PURE_FP (x) && (emin >= 1 || always_scale || (randlimb () & 1)))
     {
       mpfr_exp_t e;
       e = emin + (mpfr_exp_t) (randlimb () % (emax - emin + 1));
@@ -922,7 +923,7 @@ bad_cases (int (*fct)(FLIST), int (*inv)(FLIST), const char *name,
         printf ("bad_cases: i = %d\n", i);
       py = pymin + (randlimb () % (pymax - pymin + 1));
       mpfr_set_prec (y, py);
-      tests_default_random (y, pos, emin, emax);
+      tests_default_random (y, pos, emin, emax, 0);
       if (dbg)
         {
           printf ("bad_cases: yprec =%4ld, y = ", (long) py);
diff --git a/tests/tfprintf.c b/tests/tfprintf.c
index 26624d609..41d067f15 100644
--- a/tests/tfprintf.c
+++ b/tests/tfprintf.c
@@ -311,7 +311,7 @@ check_random (FILE *fout, int nb_tests)
       char fmt[FMT_SIZE]; /* at most something like "%-+ #0'.*R*f" */
       char *ptr = fmt;
 
-      tests_default_random (x, 256, MPFR_EMIN_MIN, MPFR_EMAX_MAX);
+      tests_default_random (x, 256, MPFR_EMIN_MIN, MPFR_EMAX_MAX, 0);
       rnd = RND_RAND ();
 
       spec = (int) (randlimb () % 5);
diff --git a/tests/tgeneric.c b/tests/tgeneric.c
index da2f33dd2..31f9f247d 100644
--- a/tests/tgeneric.c
+++ b/tests/tgeneric.c
@@ -43,6 +43,10 @@ http://www.gnu.org/licenses/ or write to the Free Software Foundation, Inc.,
 #define TEST_RANDOM_EMAX 255
 #endif
 
+#ifndef TEST_RANDOM_ALWAYS_SCALE
+#define TEST_RANDOM_ALWAYS_SCALE 0
+#endif
+
 /* If the MPFR_SUSPICIOUS_OVERFLOW test fails but this is not a bug,
    then define TGENERIC_SO_TEST with an adequate test (possibly 0) to
    omit this particular case. */
@@ -182,10 +186,12 @@ test_generic (mpfr_prec_t p0, mpfr_prec_t p1, unsigned int nmax)
 #endif
 #else
               tests_default_random (x, TEST_RANDOM_POS,
-                                    TEST_RANDOM_EMIN, TEST_RANDOM_EMAX);
+                                    TEST_RANDOM_EMIN, TEST_RANDOM_EMAX,
+                                    TEST_RANDOM_ALWAYS_SCALE);
 #if defined(TWO_ARGS) || defined(DOUBLE_ARG1) || defined(DOUBLE_ARG2)
               tests_default_random (u, TEST_RANDOM_POS2,
-                                    TEST_RANDOM_EMIN, TEST_RANDOM_EMAX);
+                                    TEST_RANDOM_EMIN, TEST_RANDOM_EMAX,
+                                    TEST_RANDOM_ALWAYS_SCALE);
 #endif
 #endif
             }
@@ -497,6 +503,7 @@ test_generic (mpfr_prec_t p0, mpfr_prec_t p1, unsigned int nmax)
 #undef TEST_RANDOM_POS2
 #undef TEST_RANDOM_EMIN
 #undef TEST_RANDOM_EMAX
+#undef TEST_RANDOM_ALWAYS_SCALE
 #undef RAND_FUNCTION
 #undef TWO_ARGS
 #undef TWO_ARGS_UI
diff --git a/tests/tprintf.c b/tests/tprintf.c
index 157e7c5ab..7c685264b 100644
--- a/tests/tprintf.c
+++ b/tests/tprintf.c
@@ -338,7 +338,7 @@ check_random (int nb_tests)
       char fmt[FMT_SIZE]; /* at most something like "%-+ #0'.*R*f" */
       char *ptr = fmt;
 
-      tests_default_random (x, 256, MPFR_EMIN_MIN, MPFR_EMAX_MAX);
+      tests_default_random (x, 256, MPFR_EMIN_MIN, MPFR_EMAX_MAX, 0);
       rnd = (mpfr_rnd_t) RND_RAND ();
 
       spec = (int) (randlimb () % 5);
diff --git a/tests/tsin_cos.c b/tests/tsin_cos.c
index c3fcb5d83..789c40da6 100644
--- a/tests/tsin_cos.c
+++ b/tests/tsin_cos.c
@@ -585,7 +585,7 @@ consistency (void)
         }
       else
         {
-          tests_default_random (x, 256, -5, 50);
+          tests_default_random (x, 256, -5, 50, 0);
           rnd = RND_RAND ();
           flags_before = (randlimb () & 1) ?
             (unsigned int) (MPFR_FLAGS_ALL ^ MPFR_FLAGS_ERANGE) :
diff --git a/tests/tsum.c b/tests/tsum.c
index 28f2cf984..ea94225b4 100644
--- a/tests/tsum.c
+++ b/tests/tsum.c
@@ -828,7 +828,8 @@ cancel (void)
 
               e = (i & 1) ? 0 : mpfr_get_emin ();
               tests_default_random (x[n], 256, e,
-                                    ((i & 2) ? e + 2000 : mpfr_get_emax ()));
+                                    ((i & 2) ? e + 2000 : mpfr_get_emax ()),
+                                    0);
             }
           else
             {