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/* 64-bit floating point to 128-bit floating point.
Copyright (C) 1997 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., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA. */
#include <quad_float.h>
/* long double _q_dtoq(double a);
Convert 'a' to long double. Don't raise exceptions.
*/
void
__q_dtoq(unsigned long long result[2], double a)
{
unsigned ux, rx;
union {
double d;
unsigned long long u;
} u;
u.d = a;
result[1] = u.u << 64-4;
result[0] = u.u >> 4;
/* correct exponent bias */
rx = ((long long)u.u >> 52 & 0x87ff) + 16383-1023;
ux = u.u >> 52 & 0x7ff;
if (ux == 0)
{
if ((u.u & 0x7fffffffffffffffULL) == 0)
{
/* +0.0 or -0.0. */
rx &= 0x8000;
}
else
{
/* Denormalised number. Renormalise. */
unsigned long long um = u.u & 0x000fffffffffffffULL;
int cs = cntlzd(um) - 12 + 1;
rx -= cs;
um <<= cs;
result[0] = um >> 4;
result[1] = um << 64-4;
}
}
else if (ux == 0x7ff)
{
/* Inf or NaN. */
rx |= 0x7fff;
}
*(unsigned short *)result = rx;
}
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