1/* Round argument to nearest integral value according to current rounding
2   direction.
3   Copyright (C) 1997, 1999, 2004, 2006 Free Software Foundation, Inc.
4   This file is part of the GNU C Library.
5   Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997 and
6   		  Jakub Jelinek <jj@ultra.linux.cz>, 1999.
7
8   The GNU C Library is free software; you can redistribute it and/or
9   modify it under the terms of the GNU Lesser General Public
10   License as published by the Free Software Foundation; either
11   version 2.1 of the License, or (at your option) any later version.
12
13   The GNU C Library is distributed in the hope that it will be useful,
14   but WITHOUT ANY WARRANTY; without even the implied warranty of
15   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
16   Lesser General Public License for more details.
17
18   You should have received a copy of the GNU Lesser General Public
19   License along with the GNU C Library; if not, write to the Free
20   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
21   02111-1307 USA.  */
22
23#include "quadmath-imp.h"
24
25static const __float128 two112[2] =
26{
27  5.19229685853482762853049632922009600E+33Q, /* 0x406F000000000000, 0 */
28 -5.19229685853482762853049632922009600E+33Q  /* 0xC06F000000000000, 0 */
29};
30
31long int
32lrintq (__float128 x)
33{
34  int32_t j0;
35  uint64_t i0,i1;
36  volatile __float128 w;
37  __float128 t;
38  long int result;
39  int sx;
40
41  GET_FLT128_WORDS64 (i0, i1, x);
42  j0 = ((i0 >> 48) & 0x7fff) - 0x3fff;
43  sx = i0 >> 63;
44  i0 &= 0x0000ffffffffffffLL;
45  i0 |= 0x0001000000000000LL;
46
47  if (j0 < 48)
48    {
49      w = two112[sx] + x;
50      t = w - two112[sx];
51      GET_FLT128_WORDS64 (i0, i1, t);
52      j0 = ((i0 >> 48) & 0x7fff) - 0x3fff;
53      i0 &= 0x0000ffffffffffffLL;
54      i0 |= 0x0001000000000000LL;
55
56      result = (j0 < 0 ? 0 : i0 >> (48 - j0));
57    }
58  else if (j0 < (int32_t) (8 * sizeof (long int)) - 1)
59    {
60      if (j0 >= 112)
61	result = ((long int) i0 << (j0 - 48)) | (i1 << (j0 - 112));
62      else
63	{
64	  w = two112[sx] + x;
65	  t = w - two112[sx];
66	  GET_FLT128_WORDS64 (i0, i1, t);
67	  j0 = ((i0 >> 48) & 0x7fff) - 0x3fff;
68	  i0 &= 0x0000ffffffffffffLL;
69	  i0 |= 0x0001000000000000LL;
70
71	  if (j0 == 48)
72	    result = (long int) i0;
73	  else
74	    result = ((long int) i0 << (j0 - 48)) | (i1 >> (112 - j0));
75	}
76    }
77  else
78    {
79      /* The number is too large.  It is left implementation defined
80	 what happens.  */
81      return (long int) x;
82    }
83
84  return sx ? -result : result;
85}
86