2 * This file is part of the GROMACS molecular simulation package.
4 * Copyright (c) 2012,2013,2014,2015,2017,2019, by the GROMACS development team, led by
5 * Mark Abraham, David van der Spoel, Berk Hess, and Erik Lindahl,
6 * and including many others, as listed in the AUTHORS file in the
7 * top-level source directory and at http://www.gromacs.org.
9 * GROMACS is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU Lesser General Public License
11 * as published by the Free Software Foundation; either version 2.1
12 * of the License, or (at your option) any later version.
14 * GROMACS is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17 * Lesser General Public License for more details.
19 * You should have received a copy of the GNU Lesser General Public
20 * License along with GROMACS; if not, see
21 * http://www.gnu.org/licenses, or write to the Free Software Foundation,
22 * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
24 * If you want to redistribute modifications to GROMACS, please
25 * consider that scientific software is very special. Version
26 * control is crucial - bugs must be traceable. We will be happy to
27 * consider code for inclusion in the official distribution, but
28 * derived work must not be called official GROMACS. Details are found
29 * in the README & COPYING files - if they are missing, get the
30 * official version at http://www.gromacs.org.
32 * To help us fund GROMACS development, we humbly ask that you cite
33 * the research papers on the package. Check out http://www.gromacs.org.
39 * Implements utility functions used by all nbnxm CPU kernels.
41 * \author Berk Hess <hess@kth.se>
42 * \ingroup module_nbnxm
47 #include "kernel_common.h"
49 #include "gromacs/pbcutil/ishift.h"
50 #include "gromacs/utility/gmxassert.h"
52 //! Clears all elements of buffer
54 clearBufferAll(gmx::ArrayRef<real> buffer)
56 for (real &elem : buffer)
62 /*! \brief Clears elements of size and stride \p numComponentsPerElement
64 * Only elements with flags in \p nbat set for index \p outputIndex
67 template <int numComponentsPerElement>
69 clearBufferFlagged(const nbnxn_atomdata_t &nbat,
71 gmx::ArrayRef<real> buffer)
73 const nbnxn_buffer_flags_t &flags = nbat.buffer_flags;
74 gmx_bitmask_t our_flag;
75 bitmask_init_bit(&our_flag, outputIndex);
77 constexpr size_t numComponentsPerBlock = NBNXN_BUFFERFLAG_SIZE*numComponentsPerElement;
79 for (int b = 0; b < flags.nflag; b++)
81 if (!bitmask_is_disjoint(flags.flag[b], our_flag))
83 clearBufferAll(buffer.subArray(b*numComponentsPerBlock, numComponentsPerBlock));
89 clearForceBuffer(nbnxn_atomdata_t *nbat,
92 if (nbat->bUseBufferFlags)
94 GMX_ASSERT(nbat->fstride == DIM, "Only fstride=3 is currently handled here");
96 clearBufferFlagged<DIM>(*nbat, outputIndex, nbat->out[outputIndex].f);
100 clearBufferAll(nbat->out[outputIndex].f);
105 clear_fshift(real *fshift)
109 for (i = 0; i < SHIFTS*DIM; i++)
116 reduce_energies_over_lists(const nbnxn_atomdata_t *nbat,
121 const int nenergrp = nbat->params().nenergrp;
123 for (int nb = 0; nb < nlist; nb++)
125 for (int i = 0; i < nenergrp; i++)
127 /* Reduce the diagonal terms */
128 int ind = i*nenergrp + i;
129 Vvdw[ind] += nbat->out[nb].Vvdw[ind];
130 Vc[ind] += nbat->out[nb].Vc[ind];
132 /* Reduce the off-diagonal terms */
133 for (int j = i + 1; j < nenergrp; j++)
135 /* The output should contain only one off-diagonal part */
136 int ind = i*nenergrp + j;
137 int indr = j*nenergrp + i;
138 Vvdw[ind] += nbat->out[nb].Vvdw[ind] + nbat->out[nb].Vvdw[indr];
139 Vc[ind] += nbat->out[nb].Vc[ind] + nbat->out[nb].Vc[indr];