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-rw-r--r--Build/source/libs/mpfr/mpfr-src/src/next.c53
1 files changed, 31 insertions, 22 deletions
diff --git a/Build/source/libs/mpfr/mpfr-src/src/next.c b/Build/source/libs/mpfr/mpfr-src/src/next.c
index e6420f20464..7fd668f6e4e 100644
--- a/Build/source/libs/mpfr/mpfr-src/src/next.c
+++ b/Build/source/libs/mpfr/mpfr-src/src/next.c
@@ -21,20 +21,29 @@ along with the GNU MPFR Library; see the file COPYING.LESSER. If not, see
http://www.gnu.org/licenses/ or write to the Free Software Foundation, Inc.,
51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA. */
+/* Note concerning the exceptions: In case of NaN result, the NaN flag is
+ * set as usual. No underflow or overflow is generated (this contradicts
+ * the obsolete IEEE 754-1985 standard for Nextafter, but conforms to the
+ * current standard IEEE 754-2008 for nextUp and nextDown).
+ */
+
#include "mpfr-impl.h"
void
mpfr_nexttozero (mpfr_ptr x)
{
- if (MPFR_UNLIKELY(MPFR_IS_INF(x)))
- {
- mpfr_setmax (x, __gmpfr_emax);
- return;
- }
- else if (MPFR_UNLIKELY( MPFR_IS_ZERO(x) ))
+ if (MPFR_UNLIKELY (MPFR_IS_SINGULAR (x)))
{
- MPFR_CHANGE_SIGN(x);
- mpfr_setmin (x, __gmpfr_emin);
+ if (MPFR_IS_INF (x))
+ {
+ mpfr_setmax (x, __gmpfr_emax);
+ }
+ else
+ {
+ MPFR_ASSERTN (MPFR_IS_ZERO (x));
+ MPFR_CHANGE_SIGN(x);
+ mpfr_setmin (x, __gmpfr_emin);
+ }
}
else
{
@@ -46,18 +55,17 @@ mpfr_nexttozero (mpfr_ptr x)
MPFR_UNSIGNED_MINUS_MODULO (sh, MPFR_PREC(x));
xp = MPFR_MANT(x);
mpn_sub_1 (xp, xp, xn, MPFR_LIMB_ONE << sh);
- if (MPFR_UNLIKELY( MPFR_LIMB_MSB(xp[xn-1]) == 0) )
- { /* was an exact power of two: not normalized any more */
+ if (MPFR_UNLIKELY (MPFR_LIMB_MSB (xp[xn-1]) == 0))
+ { /* was an exact power of two: not normalized any more,
+ thus do not use MPFR_GET_EXP. */
mpfr_exp_t exp = MPFR_EXP (x);
- if (MPFR_UNLIKELY(exp == __gmpfr_emin))
+ if (MPFR_UNLIKELY (exp == __gmpfr_emin))
MPFR_SET_ZERO(x);
else
{
- mp_size_t i;
MPFR_SET_EXP (x, exp - 1);
- xp[0] = MP_LIMB_T_MAX << sh;
- for (i = 1; i < xn; i++)
- xp[i] = MP_LIMB_T_MAX;
+ /* The following is valid whether xn = 1 or xn > 1. */
+ xp[xn-1] |= MPFR_LIMB_HIGHBIT;
}
}
}
@@ -66,10 +74,11 @@ mpfr_nexttozero (mpfr_ptr x)
void
mpfr_nexttoinf (mpfr_ptr x)
{
- if (MPFR_UNLIKELY(MPFR_IS_INF(x)))
- return;
- else if (MPFR_UNLIKELY(MPFR_IS_ZERO(x)))
- mpfr_setmin (x, __gmpfr_emin);
+ if (MPFR_UNLIKELY (MPFR_IS_SINGULAR (x)))
+ {
+ if (MPFR_IS_ZERO (x))
+ mpfr_setmin (x, __gmpfr_emin);
+ }
else
{
mp_size_t xn;
@@ -79,12 +88,12 @@ mpfr_nexttoinf (mpfr_ptr x)
xn = MPFR_LIMB_SIZE (x);
MPFR_UNSIGNED_MINUS_MODULO (sh, MPFR_PREC(x));
xp = MPFR_MANT(x);
- if (MPFR_UNLIKELY( mpn_add_1 (xp, xp, xn, MPFR_LIMB_ONE << sh)) )
+ if (MPFR_UNLIKELY (mpn_add_1 (xp, xp, xn, MPFR_LIMB_ONE << sh)))
/* got 1.0000... */
{
mpfr_exp_t exp = MPFR_EXP (x);
- if (MPFR_UNLIKELY(exp == __gmpfr_emax))
- MPFR_SET_INF(x);
+ if (MPFR_UNLIKELY (exp == __gmpfr_emax))
+ MPFR_SET_INF (x);
else
{
MPFR_SET_EXP (x, exp + 1);