/* Check values 2^n approaching exponent overflow.
Some systems might trap on overflow, so watch out for SIGFPE. */
void
check_ieee_overflow (void)
{
static long exp;
mp_limb_t n = 1;
long i;
mp_size_t sign;
double want, got;
if (! _GMP_IEEE_FLOATS)
return;
if (tests_setjmp_sigfpe() == 0)
{
exp = 1010;
want = 1.0;
for (i = 0; i < exp; i++)
want *= 2.0;
for ( ; exp < 1050; exp++)
{
for (sign = 0; sign >= -1; sign--)
{
got = mpn_get_d (&n, (mp_size_t) 1, sign, exp);
if (got != want)
{
printf ("mpn_get_d wrong on overflow\n");
printf (" n=1\n");
printf (" exp %ld\n", exp);
printf (" sign %ld\n", (long) sign);
d_trace (" got ", got);
d_trace (" want ", want);
abort ();
}
want = -want;
}
want *= 2.0;
FORCE_DOUBLE (want);
}
}
else
{
printf ("Warning, IEEE overflow tests skipped due to SIGFPE (exp=%ld)\n", exp);
}
tests_sigfpe_done ();
}
/* Check values 2^n approaching and into IEEE denorm range.
Some systems might not support denorms, or might have traps setup, so
watch out for SIGFPE. */
void
check_ieee_denorm (void)
{
static long exp;
mp_limb_t n = 1;
long i;
mp_size_t sign;
double want, got;
if (! _GMP_IEEE_FLOATS)
return;
if (tests_setjmp_sigfpe() == 0)
{
exp = -1020;
want = 1.0;
for (i = 0; i > exp; i--)
want *= 0.5;
for ( ; exp > -1500 && want != 0.0; exp--)
{
for (sign = 0; sign >= -1; sign--)
{
got = mpn_get_d (&n, (mp_size_t) 1, sign, exp);
if (got != want)
{
printf ("mpn_get_d wrong on denorm\n");
printf (" n=1\n");
printf (" exp %ld\n", exp);
printf (" sign %ld\n", (long) sign);
d_trace (" got ", got);
d_trace (" want ", want);
abort ();
}
want = -want;
}
want *= 0.5;
FORCE_DOUBLE (want);
}
}
else
{
printf ("Warning, IEEE denorm tests skipped due to SIGFPE (exp=%ld)\n", exp);
}
tests_sigfpe_done ();
}
/* Expect large negative exponents to underflow to 0.0.
Some systems might have hardware traps for such an underflow (though
usually it's not the default), so watch out for SIGFPE. */
void
check_underflow (void)
{
static const long exp_table[] = {
-999999L, LONG_MIN,
};
static const mp_limb_t np[1] = { 1 };
static long exp;
mp_size_t nsize, sign;
double got;
int exp_i;
nsize = numberof (np);
if (tests_setjmp_sigfpe() == 0)
{
for (exp_i = 0; exp_i < numberof (exp_table); exp_i++)
{
exp = exp_table[exp_i];
for (sign = 0; sign >= -1; sign--)
{
got = mpn_get_d (np, nsize, sign, exp);
if (got != 0.0)
{
printf ("mpn_get_d wrong, didn't get 0.0 on underflow\n");
printf (" nsize %ld\n", (long) nsize);
printf (" exp %ld\n", exp);
printf (" sign %ld\n", (long) sign);
d_trace (" got ", got);
abort ();
}
}
}
}
else
{
printf ("Warning, underflow to zero tests skipped due to SIGFPE (exp=%ld)\n", exp);
}
tests_sigfpe_done ();
}