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authorRoland McGrath <roland@gnu.org>1995-02-18 01:27:10 +0000
committerRoland McGrath <roland@gnu.org>1995-02-18 01:27:10 +0000
commit28f540f45bbacd939bfd07f213bcad2bf730b1bf (patch)
tree15f07c4c43d635959c6afee96bde71fb1b3614ee /sysdeps/ieee754/mpn2flt.c
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diff --git a/sysdeps/ieee754/mpn2flt.c b/sysdeps/ieee754/mpn2flt.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 (24 for
+ float) and an integral power of two to a `float' in IEEE754 single-
+ precision format. */
+
+float
+__mpn_construct_float (mp_srcptr frac_ptr, int expt, int sign)
+{
+ union ieee754_float u;
+
+ u.ieee.negative = sign;
+ u.ieee.exponent = expt + IEEE754_FLOAT_BIAS;
+#if BITS_PER_MP_LIMB > FLT_MANT_DIG
+ u.ieee.mantissa = frac_ptr[0] & ((1 << FLT_MANT_DIG) - 1);
+#else
+ #error "mp_limb size " BITS_PER_MP_LIMB "not accounted for"
+#endif
+
+ return u.f;
+}