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-rw-r--r--libquadmath/strtod/mpn2flt128.c51
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diff --git a/libquadmath/strtod/mpn2flt128.c b/libquadmath/strtod/mpn2flt128.c
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+++ b/libquadmath/strtod/mpn2flt128.c
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+/* 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;
+}