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Diffstat (limited to 'Build/source/libs/mpfr/mpfr-src/src/sub_ui.c')
-rw-r--r--Build/source/libs/mpfr/mpfr-src/src/sub_ui.c78
1 files changed, 49 insertions, 29 deletions
diff --git a/Build/source/libs/mpfr/mpfr-src/src/sub_ui.c b/Build/source/libs/mpfr/mpfr-src/src/sub_ui.c
index 63689dd5d8b..9bca863a3aa 100644
--- a/Build/source/libs/mpfr/mpfr-src/src/sub_ui.c
+++ b/Build/source/libs/mpfr/mpfr-src/src/sub_ui.c
@@ -27,35 +27,55 @@ http://www.gnu.org/licenses/ or write to the Free Software Foundation, Inc.,
int
mpfr_sub_ui (mpfr_ptr y, mpfr_srcptr x, unsigned long int u, mpfr_rnd_t rnd_mode)
{
- if (MPFR_LIKELY (u != 0)) /* if u=0, do nothing */
+ MPFR_LOG_FUNC
+ (("x[%Pu]=%.*Rg u=%lu rnd=%d",
+ mpfr_get_prec(x), mpfr_log_prec, x, u, rnd_mode),
+ ("y[%Pu]=%.*Rg", mpfr_get_prec (y), mpfr_log_prec, y));
+
+ /* (unsigned long) 0 is assumed to be a real 0 (unsigned) */
+ if (MPFR_UNLIKELY (u == 0))
+ return mpfr_set (y, x, rnd_mode);
+
+ /* This block is actually useless, but this is a minor optimization. */
+ if (MPFR_UNLIKELY (MPFR_IS_SINGULAR (x)))
{
- mpfr_t uu;
- mp_limb_t up[1];
- unsigned long cnt;
- int inex;
-
- MPFR_SAVE_EXPO_DECL (expo);
-
- MPFR_LOG_FUNC
- (("x[%Pu]=%.*Rg u=%lu rnd=%d",
- mpfr_get_prec(x), mpfr_log_prec, x, u, rnd_mode),
- ("y[%Pu]=%.*Rg inexact=%d",
- mpfr_get_prec(y), mpfr_log_prec, y, inex));
-
- MPFR_TMP_INIT1 (up, uu, GMP_NUMB_BITS);
- MPFR_ASSERTN (u == (mp_limb_t) u);
- count_leading_zeros (cnt, (mp_limb_t) u);
- *up = (mp_limb_t) u << cnt;
-
- /* Optimization note: Exponent save/restore operations may be
- removed if mpfr_sub works even when uu is out-of-range. */
- MPFR_SAVE_EXPO_MARK (expo);
- MPFR_SET_EXP (uu, GMP_NUMB_BITS - cnt);
- inex = mpfr_sub (y, x, uu, rnd_mode);
- MPFR_SAVE_EXPO_UPDATE_FLAGS (expo, __gmpfr_flags);
- MPFR_SAVE_EXPO_FREE (expo);
- return mpfr_check_range (y, inex, rnd_mode);
+ if (MPFR_IS_NAN (x))
+ {
+ MPFR_SET_NAN (y);
+ MPFR_RET_NAN;
+ }
+ if (MPFR_IS_INF (x))
+ {
+ MPFR_SET_INF (y);
+ MPFR_SET_SAME_SIGN (y, x);
+ MPFR_RET (0); /* +/-infinity is exact */
+ }
+ /* The case x being zero is handled below: we can't use mpfr_set_si
+ as the opposite of u does not necessarily fit in a long. */
}
- else
- return mpfr_set (y, x, rnd_mode);
+
+ /* Main code */
+ {
+ mpfr_t uu;
+ mp_limb_t up[1];
+ int cnt;
+ int inex;
+ MPFR_SAVE_EXPO_DECL (expo);
+
+ MPFR_TMP_INIT1 (up, uu, GMP_NUMB_BITS);
+ MPFR_STAT_STATIC_ASSERT (MPFR_LIMB_MAX >= ULONG_MAX);
+ /* So, u fits in a mp_limb_t, which justifies the casts below. */
+ MPFR_ASSERTD (u != 0);
+ count_leading_zeros (cnt, (mp_limb_t) u);
+ *up = (mp_limb_t) u << cnt;
+
+ /* Optimization note: Exponent save/restore operations may be
+ removed if mpfr_sub works even when uu is out-of-range. */
+ MPFR_SAVE_EXPO_MARK (expo);
+ MPFR_SET_EXP (uu, GMP_NUMB_BITS - cnt);
+ inex = mpfr_sub (y, x, uu, rnd_mode);
+ MPFR_SAVE_EXPO_UPDATE_FLAGS (expo, __gmpfr_flags);
+ MPFR_SAVE_EXPO_FREE (expo);
+ return mpfr_check_range (y, inex, rnd_mode);
+ }
}