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Diffstat (limited to 'libquadmath/strtod/mpn2flt128.c')
-rw-r--r-- | libquadmath/strtod/mpn2flt128.c | 51 |
1 files changed, 51 insertions, 0 deletions
diff --git a/libquadmath/strtod/mpn2flt128.c b/libquadmath/strtod/mpn2flt128.c new file mode 100644 index 000000000..844ae97d8 --- /dev/null +++ b/libquadmath/strtod/mpn2flt128.c @@ -0,0 +1,51 @@ +/* Copyright (C) 1995,1996,1997,1998,1999,2002,2003 + Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, write to the Free + Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA + 02111-1307 USA. */ + +#include <config.h> +#include <float.h> +#include <math.h> +#include "../printf/gmp-impl.h" + +/* Convert a multi-precision integer of the needed number of bits (113 for + long double) and an integral power of two to a `long double' in IEEE854 + quad-precision format. */ + +__float128 +mpn_construct_float128 (mp_srcptr frac_ptr, int expt, int sign) +{ + ieee854_float128 u; + + u.ieee.negative = sign; + u.ieee.exponent = expt + IEEE854_FLOAT128_BIAS; +#if BITS_PER_MP_LIMB == 32 + u.ieee.mant_low = (((uint64_t) frac_ptr[1]) << 32) + | (frac_ptr[0] & 0xffffffff); + u.ieee.mant_high = (((uint64_t) frac_ptr[3] + & (((mp_limb_t) 1 << (FLT128_MANT_DIG - 96)) - 1)) + << 32) | (frac_ptr[2] & 0xffffffff); +#elif BITS_PER_MP_LIMB == 64 + u.ieee.mant_low = frac_ptr[0]; + u.ieee.mant_high = frac_ptr[1] + & (((mp_limb_t) 1 << (FLT128_MANT_DIG - 64)) - 1); +#else + #error "mp_limb size " BITS_PER_MP_LIMB "not accounted for" +#endif + + return u.value; +} |