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-rw-r--r--sysdeps/ieee754/mpn2ldbl.c46
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diff --git a/sysdeps/ieee754/mpn2ldbl.c b/sysdeps/ieee754/mpn2ldbl.c
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+/* Copyright (C) 1995 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 Library General Public License as
+published by the Free Software Foundation; either version 2 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
+Library General Public License for more details.
+
+You should have received a copy of the GNU Library General Public
+License along with the GNU C Library; see the file COPYING.LIB. If
+not, write to the Free Software Foundation, Inc., 675 Mass Ave,
+Cambridge, MA 02139, USA. */
+
+#include "gmp.h"
+#include "gmp-impl.h"
+#include "ieee754.h"
+#include <float.h>
+
+/* Convert a multi-precision integer of the needed number of bits (64 for
+ long double) and an integral power of two to a `long double' in IEEE854
+ extended-precision format. */
+
+long double
+__mpn_construct_long_double (mp_srcptr frac_ptr, int expt, int sign)
+{
+ union ieee854_long_double u;
+
+ u.ieee.negative = sign;
+ u.ieee.exponent = expt + IEEE854_LONG_DOUBLE_BIAS;
+#if BITS_PER_MP_LIMB == 32
+ u.ieee.mantissa1 = frac_ptr[0];
+ u.ieee.mantissa0 = frac_ptr[1];
+#elif BITS_PER_MP_LIMB == 64
+ u.ieee.mantissa1 = frac_ptr[0] & ((1 << 32) - 1);
+ i.ieee.mantissa0 = frac_ptr[0] >> 32;
+#else
+ #error "mp_limb size " BITS_PER_MP_LIMB "not accounted for"
+#endif
+
+ return u.d;
+}