diff options
Diffstat (limited to 'set_d.c')
| -rw-r--r-- | set_d.c | 29 |
1 files changed, 24 insertions, 5 deletions
@@ -1,7 +1,7 @@ /* mpfr_set_d -- convert a machine double precision float to a multiple precision floating-point number -Copyright 1999, 2000, 2001, 2002, 2003 Free Software Foundation, Inc. +Copyright 1999, 2000, 2001, 2002, 2003, 2004 Free Software Foundation, Inc. This file is part of the MPFR Library. @@ -155,19 +155,38 @@ mpfr_set_d (mpfr_ptr r, double d, mp_rnd_t rnd_mode) mp_size_t i, k; mpfr_t tmp; mp_limb_t tmpmant[MPFR_LIMBS_PER_DOUBLE]; - + MPFR_CLEAR_FLAGS(r); if (d == 0) { +#if _GMP_IEEE_FLOATS union ieee_double_extract x; MPFR_SET_ZERO(r); /* set correct sign */ x.d = d; - if (((x.s.sig == 1) && (MPFR_SIGN(r) > 0)) - || ((x.s.sig == 0) && (MPFR_SIGN(r) < 0))) - MPFR_CHANGE_SIGN(r); + if (x.s.sig == 1) + MPFR_SET_NEG(r); + else + MPFR_SET_POS(r); +#else /* _GMP_IEEE_FLOATS */ + MPFR_SET_ZERO(r); + { + /* This is to get the sign of zero on non-IEEE hardware + Some systems support +0.0, -0.0 and unsigned zero. + We can't use d==+0.0 since it should be always true, + so we check that the memory representation of d is the + same than +0.0. etc */ + double poszero = +0.0, negzero = -0.0; + if (memcmp(&d, &poszero, sizeof(double)) == 0) + MPFR_SET_POS(r); + else if (memcmp(&d, &negzero, sizeof(double)) == 0) + MPFR_SET_NEG(r); + else + MPFR_SET_POS(r); + } +#endif return 0; /* 0 is exact */ } else if (DOUBLE_ISNAN(d)) |