78 lines
2.6 KiB
C
78 lines
2.6 KiB
C
/*
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Copyright 2009, 2011 William Hart. All rights reserved.
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Redistribution and use in source and binary forms, with or without modification, are
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permitted provided that the following conditions are met:
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1. Redistributions of source code must retain the above copyright notice, this list of
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conditions and the following disclaimer.
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2. Redistributions in binary form must reproduce the above copyright notice, this list
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of conditions and the following disclaimer in the documentation and/or other materials
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provided with the distribution.
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THIS SOFTWARE IS PROVIDED BY William Hart ``AS IS'' AND ANY EXPRESS OR IMPLIED
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WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
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FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL William Hart OR
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CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
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CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
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SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
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ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
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NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
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ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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The views and conclusions contained in the software and documentation are those of the
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authors and should not be interpreted as representing official policies, either expressed
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or implied, of William Hart.
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*/
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#include "mpir.h"
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#include "gmp-impl.h"
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#include "longlong.h"
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#include "fft/fft_tuning.h"
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static mp_size_t mulmod_2expp1_table_n[FFT_N_NUM] = MULMOD_TAB;
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int mpn_mulmod_Bexpp1(mp_ptr r, mp_srcptr i1, mp_srcptr i2, mp_size_t limbs, mp_ptr tt)
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{
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mp_size_t bits = limbs * GMP_LIMB_BITS;
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mp_bitcnt_t depth1, depth = 1;
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mp_size_t w1, off;
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mp_limb_t c = 2 * i1[limbs] + i2[limbs];
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if (c & 1)
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{
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mpn_neg_n(r, i1, limbs + 1);
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mpn_normmod_2expp1(r, limbs);
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return 0;
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} else if (c & 2)
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{
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mpn_neg_n(r, i2, limbs + 1);
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mpn_normmod_2expp1(r, limbs);
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return 0;
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}
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if (limbs <= FFT_MULMOD_2EXPP1_CUTOFF)
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{
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if(bits)
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r[limbs] = mpn_mulmod_2expp1_basecase(r, i1, i2, c, bits, tt);
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else
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r[limbs] = 0;
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return r[limbs];
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}
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while ((((mp_limb_t)1)<<depth) < bits) depth++;
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if (depth < 12) off = mulmod_2expp1_table_n[0];
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else off = mulmod_2expp1_table_n[MIN(depth, FFT_N_NUM + 11) - 12];
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depth1 = depth/2 - off;
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w1 = bits/(((mp_limb_t)1)<<(2*depth1));
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mpir_fft_mulmod_2expp1(r, i1, i2, limbs, depth1, w1);
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return r[limbs];
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}
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