1/* mpn_sqr -- square natural numbers.
2
3Copyright 1991, 1993, 1994, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003,
42005, 2008, 2009 Free Software Foundation, Inc.
5
6This file is part of the GNU MP Library.
7
8The GNU MP Library is free software; you can redistribute it and/or modify
9it under the terms of the GNU Lesser General Public License as published by
10the Free Software Foundation; either version 3 of the License, or (at your
11option) any later version.
12
13The GNU MP Library is distributed in the hope that it will be useful, but
14WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
15or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public
16License for more details.
17
18You should have received a copy of the GNU Lesser General Public License
19along with the GNU MP Library.  If not, see http://www.gnu.org/licenses/.  */
20
21#include "gmp.h"
22#include "gmp-impl.h"
23#include "longlong.h"
24
25void
26mpn_sqr (mp_ptr p, mp_srcptr a, mp_size_t n)
27{
28  ASSERT (n >= 1);
29  ASSERT (! MPN_OVERLAP_P (p, 2 * n, a, n));
30
31  if (BELOW_THRESHOLD (n, SQR_BASECASE_THRESHOLD))
32    { /* mul_basecase is faster than sqr_basecase on small sizes sometimes */
33      mpn_mul_basecase (p, a, n, a, n);
34    }
35  else if (BELOW_THRESHOLD (n, SQR_TOOM2_THRESHOLD))
36    {
37      mpn_sqr_basecase (p, a, n);
38    }
39  else if (BELOW_THRESHOLD (n, SQR_TOOM3_THRESHOLD))
40    {
41      /* Allocate workspace of fixed size on stack: fast! */
42      mp_limb_t ws[mpn_toom2_sqr_itch (SQR_TOOM3_THRESHOLD_LIMIT-1)];
43      ASSERT (SQR_TOOM3_THRESHOLD <= SQR_TOOM3_THRESHOLD_LIMIT);
44      mpn_toom2_sqr (p, a, n, ws);
45    }
46  else if (BELOW_THRESHOLD (n, SQR_TOOM4_THRESHOLD))
47    {
48      mp_ptr ws;
49      TMP_SDECL;
50      TMP_SMARK;
51      ws = TMP_SALLOC_LIMBS (mpn_toom3_sqr_itch (n));
52      mpn_toom3_sqr (p, a, n, ws);
53      TMP_SFREE;
54    }
55  else if (BELOW_THRESHOLD (n, SQR_TOOM6_THRESHOLD))
56    {
57      mp_ptr ws;
58      TMP_SDECL;
59      TMP_SMARK;
60      ws = TMP_SALLOC_LIMBS (mpn_toom4_sqr_itch (n));
61      mpn_toom4_sqr (p, a, n, ws);
62      TMP_SFREE;
63    }
64  else if (BELOW_THRESHOLD (n, SQR_TOOM8_THRESHOLD))
65    {
66      mp_ptr ws;
67      TMP_SDECL;
68      TMP_SMARK;
69      ws = TMP_SALLOC_LIMBS (mpn_toom6_sqr_itch (n));
70      mpn_toom6_sqr (p, a, n, ws);
71      TMP_SFREE;
72    }
73  else if (BELOW_THRESHOLD (n, SQR_FFT_THRESHOLD))
74    {
75      mp_ptr ws;
76      TMP_DECL;
77      TMP_MARK;
78      ws = TMP_ALLOC_LIMBS (mpn_toom8_sqr_itch (n));
79      mpn_toom8_sqr (p, a, n, ws);
80      TMP_FREE;
81    }
82  else
83    {
84      /* The current FFT code allocates its own space.  That should probably
85	 change.  */
86      mpn_fft_mul (p, a, n, a, n);
87    }
88}
89