diff options
Diffstat (limited to 'Build/source/libs/mpfr/mpfr-src/src/get_sj.c')
-rw-r--r-- | Build/source/libs/mpfr/mpfr-src/src/get_sj.c | 54 |
1 files changed, 25 insertions, 29 deletions
diff --git a/Build/source/libs/mpfr/mpfr-src/src/get_sj.c b/Build/source/libs/mpfr/mpfr-src/src/get_sj.c index 2e217787ca4..05274848c24 100644 --- a/Build/source/libs/mpfr/mpfr-src/src/get_sj.c +++ b/Build/source/libs/mpfr/mpfr-src/src/get_sj.c @@ -1,6 +1,6 @@ /* mpfr_get_sj -- convert a MPFR number to a huge machine signed integer -Copyright 2004, 2006-2019 Free Software Foundation, Inc. +Copyright 2004, 2006-2020 Free Software Foundation, Inc. Contributed by the AriC and Caramba projects, INRIA. This file is part of the GNU MPFR Library. @@ -20,11 +20,7 @@ along with the GNU MPFR Library; see the file COPYING.LESSER. If not, see https://www.gnu.org/licenses/ or write to the Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA. */ -#ifdef HAVE_CONFIG_H -# include "config.h" -#endif - -#include "mpfr-intmax.h" +#define MPFR_NEED_INTMAX_H #include "mpfr-impl.h" #ifdef _MPFR_H_HAVE_INTMAX_T @@ -41,7 +37,7 @@ mpfr_get_sj (mpfr_srcptr f, mpfr_rnd_t rnd) { MPFR_SET_ERANGEFLAG (); return MPFR_IS_NAN (f) ? 0 : - MPFR_IS_NEG (f) ? MPFR_INTMAX_MIN : MPFR_INTMAX_MAX; + MPFR_IS_NEG (f) ? INTMAX_MIN : INTMAX_MAX; } if (MPFR_IS_ZERO (f)) @@ -50,7 +46,7 @@ mpfr_get_sj (mpfr_srcptr f, mpfr_rnd_t rnd) /* Determine the precision of intmax_t. |INTMAX_MIN| may have one more bit as an integer, but in this case, this is a power of 2, thus fits in a precision-prec floating-point number. */ - for (r = MPFR_INTMAX_MAX, prec = 0; r != 0; r /= 2, prec++) + for (r = INTMAX_MAX, prec = 0; r != 0; r /= 2, prec++) { } MPFR_ASSERTD (r == 0); @@ -68,24 +64,31 @@ mpfr_get_sj (mpfr_srcptr f, mpfr_rnd_t rnd) if (MPFR_NOTZERO (x)) { mp_limb_t *xp; - int sh, n; /* An int should be sufficient in this context. */ + int sh; /* An int should be sufficient in this context. */ xp = MPFR_MANT (x); sh = MPFR_GET_EXP (x); MPFR_ASSERTN ((mpfr_prec_t) sh <= prec + 1); - if (MPFR_INTMAX_MIN + MPFR_INTMAX_MAX != 0 + if (INTMAX_MIN + INTMAX_MAX != 0 && MPFR_UNLIKELY ((mpfr_prec_t) sh > prec)) { /* 2's complement and x <= INTMAX_MIN: in the case mp_limb_t has the same size as intmax_t, we cannot use the code in the for loop since the operations would be performed in unsigned arithmetic. */ - MPFR_ASSERTN (MPFR_IS_NEG (x) && mpfr_powerof2_raw (x)); - r = MPFR_INTMAX_MIN; + MPFR_ASSERTD (MPFR_IS_NEG (x) && mpfr_powerof2_raw (x)); + r = INTMAX_MIN; } - else if (MPFR_IS_POS (x)) + /* sh is the number of bits that remain to be considered in {xp, xn} */ + else { - /* Note: testing the condition sh >= 0 is necessary to avoid +#ifdef MPFR_INTMAX_WITHIN_LIMB + MPFR_ASSERTD (sh > 0 && sh < GMP_NUMB_BITS); + r = xp[0] >> (GMP_NUMB_BITS - sh); +#else + int n; + + /* Note: testing the condition sh > 0 is necessary to avoid an undefined behavior on xp[n] >> S when S >= GMP_NUMB_BITS (even though xp[n] == 0 in such a case). This can happen if sizeof(mp_limb_t) < sizeof(intmax_t) and |x| is small enough @@ -101,22 +104,15 @@ mpfr_get_sj (mpfr_srcptr f, mpfr_rnd_t rnd) mp_limb_t is unsigned, therefore not representable as an intmax_t when the MSB is 1 (this is the case here). */ MPFR_ASSERTD (-sh < GMP_NUMB_BITS); - r += (sh >= 0 - ? (intmax_t) xp[n] << sh - : (intmax_t) (xp[n] >> (-sh))); - } - } - else - { - /* See the comments for the case x positive. */ - for (n = MPFR_LIMB_SIZE (x) - 1; n >= 0 && sh > 0; n--) - { - sh -= GMP_NUMB_BITS; - MPFR_ASSERTD (-sh < GMP_NUMB_BITS); - r -= (sh >= 0 - ? (intmax_t) xp[n] << sh - : (intmax_t) (xp[n] >> (-sh))); + /* each limb should be shifted by sh bits to the left if sh>=0, + and by sh bits to the right if sh < 0 */ + r += sh >= 0 + ? (intmax_t) xp[n] << sh + : (intmax_t) (xp[n] >> (-sh)); } +#endif + if (MPFR_IS_NEG(x)) + r = -r; } } |