1 /* mpn_mul_n -- multiply natural numbers. 2 3 Copyright 1991, 1993, 1994, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 4 2005, 2008, 2009 Free Software Foundation, Inc. 5 6 This file is part of the GNU MP Library. 7 8 The GNU MP Library is free software; you can redistribute it and/or modify 9 it under the terms of the GNU Lesser General Public License as published by 10 the Free Software Foundation; either version 3 of the License, or (at your 11 option) any later version. 12 13 The GNU MP Library is distributed in the hope that it will be useful, but 14 WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY 15 or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public 16 License for more details. 17 18 You should have received a copy of the GNU Lesser General Public License 19 along 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 25 void 26 mpn_mul_n (mp_ptr p, mp_srcptr a, mp_srcptr b, mp_size_t n) 27 { 28 ASSERT (n >= 1); 29 ASSERT (! MPN_OVERLAP_P (p, 2 * n, a, n)); 30 ASSERT (! MPN_OVERLAP_P (p, 2 * n, b, n)); 31 32 if (BELOW_THRESHOLD (n, MUL_TOOM22_THRESHOLD)) 33 { 34 mpn_mul_basecase (p, a, n, b, n); 35 } 36 else if (BELOW_THRESHOLD (n, MUL_TOOM33_THRESHOLD)) 37 { 38 /* Allocate workspace of fixed size on stack: fast! */ 39 mp_limb_t ws[mpn_toom22_mul_itch (MUL_TOOM33_THRESHOLD_LIMIT-1, 40 MUL_TOOM33_THRESHOLD_LIMIT-1)]; 41 ASSERT (MUL_TOOM33_THRESHOLD <= MUL_TOOM33_THRESHOLD_LIMIT); 42 mpn_toom22_mul (p, a, n, b, n, ws); 43 } 44 else if (BELOW_THRESHOLD (n, MUL_TOOM44_THRESHOLD)) 45 { 46 mp_ptr ws; 47 TMP_SDECL; 48 TMP_SMARK; 49 ws = TMP_SALLOC_LIMBS (mpn_toom33_mul_itch (n, n)); 50 mpn_toom33_mul (p, a, n, b, n, ws); 51 TMP_SFREE; 52 } 53 else if (BELOW_THRESHOLD (n, MUL_TOOM6H_THRESHOLD)) 54 { 55 mp_ptr ws; 56 TMP_SDECL; 57 TMP_SMARK; 58 ws = TMP_SALLOC_LIMBS (mpn_toom44_mul_itch (n, n)); 59 mpn_toom44_mul (p, a, n, b, n, ws); 60 TMP_SFREE; 61 } 62 else if (BELOW_THRESHOLD (n, MUL_TOOM8H_THRESHOLD)) 63 { 64 mp_ptr ws; 65 TMP_SDECL; 66 TMP_SMARK; 67 ws = TMP_SALLOC_LIMBS (mpn_toom6_mul_n_itch (n)); 68 mpn_toom6h_mul (p, a, n, b, n, ws); 69 TMP_SFREE; 70 } 71 else if (BELOW_THRESHOLD (n, MUL_FFT_THRESHOLD)) 72 { 73 mp_ptr ws; 74 TMP_DECL; 75 TMP_MARK; 76 ws = TMP_ALLOC_LIMBS (mpn_toom8_mul_n_itch (n)); 77 mpn_toom8h_mul (p, a, n, b, n, ws); 78 TMP_FREE; 79 } 80 else 81 { 82 /* The current FFT code allocates its own space. That should probably 83 change. */ 84 mpn_fft_mul (p, a, n, b, n); 85 } 86 } 87