summaryrefslogtreecommitdiff
path: root/sqrt_ui.c
blob: dbeb070efe2893a7f9710fa928ab07e532c7d760 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
/* mpfr_sqrt_ui -- square root of a machine integer

Copyright (C) 2000 PolKA project, Inria Lorraine and Loria

This file is part of the MPFR Library.

The MPFR 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 MPFR 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 MPFR 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. */

#define MON_INIT(xp, x, p, s) xp = (mp_ptr) TMP_ALLOC(s*BYTES_PER_MP_LIMB);    x -> _mp_prec = p; x -> _mp_d = xp; x -> _mp_size = s;

#include <math.h>
#include <stdio.h>
#include <stdlib.h>
#include "gmp.h"
#include "gmp-impl.h"
#include "mpfr.h"
#include "longlong.h"

int
#if __STDC__
mpfr_sqrt_ui (mpfr_ptr r, unsigned long u, mp_rnd_t rnd_mode)
#else
mpfr_sqrt_ui (r, u, rnd_mode)
     mpfr_ptr r;
     unsigned long u;
     mp_rnd_t rnd_mode;
#endif
{
  int exact=1;
  mpfr_t uu;
  mp_limb_t *up;
  unsigned long cnt;
  TMP_DECL(marker);

  if (u) { /* if u=0, do nothing */
    MON_INIT(up, uu, BITS_PER_MP_LIMB, 1);
    count_leading_zeros(cnt, (mp_limb_t) u);
    *up = (mp_limb_t) u << cnt;
    EXP(uu) = BITS_PER_MP_LIMB-cnt;

    exact = mpfr_sqrt(r, uu, rnd_mode);

    TMP_FREE(marker);
  }
  else SET_ZERO(r);
  return exact;
}