glibc/sysdeps/m68k/fpu/s_llrint.c

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/* Round argument to nearest integral value according to current rounding
direction.
Copyright (C) 1997 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Andreas Schwab <schwab@issan.informatik.uni-dortmund.de>
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 <math.h>
#include "math_private.h"
long long int
__llrint (double x)
{
int32_t e;
u_int32_t h, l, s;
long long int result;
x = __m81_u(__rint) (x);
/* We could use __fixxfdi from libgcc, but here we can take advantage of
the known floating point format. */
EXTRACT_WORDS (h, l, x);
e = ((h >> 20) & 0x7ff) - 0x3ff;
if (e < 0)
return 0;
s = h;
h &= 0xfffff;
h |= 0x100000;
if (e < 63)
{
if (e > 52)
{
h <<= e - 52;
h |= l >> (84 - e);
l <<= e - 52;
result = ((long long int) h << 32) | l;
}
else if (e > 20)
{
l >>= 52 - e;
l |= h << (e - 20);
h >>= 52 - e;
result = ((long long int) h << 32) | l;
}
else
result = h >> (20 - e);
if (s & 0x80000000)
result = -result;
}
else
/* The number is too large or not finite. The standard leaves it
undefined what to return when the number is too large to fit in a
`long long int'. */
result = -1LL;
return result;
}
weak_alias (__llrint, llrint)