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Diffstat (limited to 'src/fftw3/dft/buffered.c')
-rw-r--r-- | src/fftw3/dft/buffered.c | 323 |
1 files changed, 323 insertions, 0 deletions
diff --git a/src/fftw3/dft/buffered.c b/src/fftw3/dft/buffered.c new file mode 100644 index 0000000..763ebe3 --- /dev/null +++ b/src/fftw3/dft/buffered.c @@ -0,0 +1,323 @@ +/* + * Copyright (c) 2003 Matteo Frigo + * Copyright (c) 2003 Massachusetts Institute of Technology + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program 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 General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + * + */ + +/* $Id: buffered.c,v 1.1 2008/10/17 06:11:08 scuri Exp $ */ + +#include "dft.h" + +typedef struct { + int nbuf; + int maxbufsz; + int skew_alignment; + int skew; + const char *nam; +} bufadt; + +typedef struct { + solver super; + const bufadt *adt; +} S; + +typedef struct { + plan_dft super; + + plan *cld, *cldcpy, *cldrest; + int n, vl, nbuf, bufdist; + int ivs, ovs; + int roffset, ioffset; + + const S *slv; +} P; + +/* transform a vector input with the help of bufs */ +static void apply(const plan *ego_, R *ri, R *ii, R *ro, R *io) +{ + const P *ego = (const P *) ego_; + int nbuf = ego->nbuf; + R *bufs = (R *)MALLOC(sizeof(R) * nbuf * ego->bufdist * 2, BUFFERS); + + plan_dft *cld = (plan_dft *) ego->cld; + plan_dft *cldcpy = (plan_dft *) ego->cldcpy; + plan_dft *cldrest; + int i, vl = ego->vl; + int ivs = ego->ivs, ovs = ego->ovs; + int roffset = ego->roffset, ioffset = ego->ioffset; + + /* note unsigned i: the obvious statement + + for (i = 0; i <= vl - nbuf; i += nbuf) + + is wrong */ + for (i = nbuf; i <= vl; i += nbuf) { + /* transform to bufs: */ + cld->apply((plan *) cld, ri, ii, bufs + roffset, bufs + ioffset); + ri += ivs; ii += ivs; + + /* copy back */ + cldcpy->apply((plan *) cldcpy, bufs+roffset, bufs+ioffset, ro, io); + ro += ovs; io += ovs; + } + + /* Do the remaining transforms, if any: */ + cldrest = (plan_dft *) ego->cldrest; + cldrest->apply((plan *) cldrest, ri, ii, ro, io); + + X(ifree)(bufs); +} + + +static void awake(plan *ego_, int flg) +{ + P *ego = (P *) ego_; + + AWAKE(ego->cld, flg); + AWAKE(ego->cldcpy, flg); + AWAKE(ego->cldrest, flg); +} + +static void destroy(plan *ego_) +{ + P *ego = (P *) ego_; + X(plan_destroy_internal)(ego->cldrest); + X(plan_destroy_internal)(ego->cldcpy); + X(plan_destroy_internal)(ego->cld); +} + +static void print(const plan *ego_, printer *p) +{ + const P *ego = (const P *) ego_; + p->print(p, "(%s-%d%v/%d-%d%(%p%)%(%p%)%(%p%))", + ego->slv->adt->nam, + ego->n, ego->nbuf, + ego->vl, ego->bufdist % ego->n, + ego->cld, ego->cldcpy, ego->cldrest); +} + +static int compute_nbuf(int n, int vl, const S *ego) +{ + return X(compute_nbuf)(n, vl, ego->adt->nbuf, ego->adt->maxbufsz); +} + +static int toobig(int n, const S *ego) +{ + return (n > ego->adt->maxbufsz); +} + +static int applicable0(const problem *p_, const S *ego, const planner *plnr) +{ + if (DFTP(p_)) { + const problem_dft *p = (const problem_dft *) p_; + const iodim *d = p->sz->dims; + + if (1 + && p->vecsz->rnk <= 1 + && p->sz->rnk == 1 + ) { + + if (toobig(p->sz->dims[0].n, ego) && CONSERVE_MEMORYP(plnr)) + return 0; + + /* + In principle, the buffered transforms might be useful + when working out of place. However, in order to + prevent infinite loops in the planner, we require + that the output stride of the buffered transforms be + greater than 2. + */ + if (p->ri != p->ro) + return (d[0].os > 2); + + /* We can always do a single transform in-place */ + if (p->vecsz->rnk == 0) + return 1; + + /* + * If the problem is in place, the input/output strides must + * be the same or the whole thing must fit in the buffer. + */ + return ((X(tensor_inplace_strides2)(p->sz, p->vecsz)) + || (compute_nbuf(d[0].n, p->vecsz->dims[0].n, ego) + == p->vecsz->dims[0].n)); + } + } + return 0; +} + +static int applicable(const problem *p_, const S *ego, const planner *plnr) +{ + if (NO_BUFFERINGP(plnr)) return 0; + if (!applicable0(p_, ego, plnr)) return 0; + + if (NO_UGLYP(plnr)) { + const problem_dft *p = (const problem_dft *) p_; + if (p->ri != p->ro) return 0; + if (toobig(p->sz->dims[0].n, ego)) return 0; + } + + return 1; +} + +static plan *mkplan(const solver *ego_, const problem *p_, planner *plnr) +{ + const S *ego = (const S *) ego_; + const bufadt *adt = ego->adt; + P *pln; + plan *cld = (plan *) 0; + plan *cldcpy = (plan *) 0; + plan *cldrest = (plan *) 0; + const problem_dft *p = (const problem_dft *) p_; + R *bufs = (R *) 0; + int nbuf = 0, bufdist, n, vl; + int ivs, ovs, roffset, ioffset; + + static const plan_adt padt = { + X(dft_solve), awake, print, destroy + }; + + if (!applicable(p_, ego, plnr)) + goto nada; + + n = X(tensor_sz)(p->sz); + + X(tensor_tornk1)(p->vecsz, &vl, &ivs, &ovs); + + nbuf = compute_nbuf(n, vl, ego); + A(nbuf > 0); + + /* + * Determine BUFDIST, the offset between successive array bufs. + * bufdist = n + skew, where skew is chosen such that bufdist % + * skew_alignment = skew. + */ + if (vl == 1) { + bufdist = n; + } else { + bufdist = + n + ((adt->skew_alignment + adt->skew - n % adt->skew_alignment) + % adt->skew_alignment); + A(p->vecsz->rnk == 1); + } + + /* attempt to keep real and imaginary part in the same order, + so as to allow optimizations in the the copy plan */ + roffset = (p->ri - p->ii > 0) ? 1 : 0; + ioffset = 1 - roffset; + + /* initial allocation for the purpose of planning */ + bufs = (R *) MALLOC(sizeof(R) * nbuf * bufdist * 2, BUFFERS); + + cld = X(mkplan_d)(plnr, + X(mkproblem_dft_d)( + X(mktensor_1d)(n, p->sz->dims[0].is, 2), + X(mktensor_1d)(nbuf, ivs, bufdist * 2), + TAINT(p->ri, ivs * nbuf), + TAINT(p->ii, ivs * nbuf), + bufs + roffset, + bufs + ioffset)); + if (!cld) + goto nada; + + /* copying back from the buffer is a rank-0 transform: */ + cldcpy = X(mkplan_d)(plnr, + X(mkproblem_dft_d)( + X(mktensor_0d)(), + X(mktensor_2d)(nbuf, bufdist * 2, ovs, + n, 2, p->sz->dims[0].os), + bufs + roffset, + bufs + ioffset, + TAINT(p->ro, ovs * nbuf), + TAINT(p->io, ovs * nbuf))); + if (!cldcpy) + goto nada; + + /* deallocate buffers, let apply() allocate them for real */ + X(ifree)(bufs); + bufs = 0; + + /* plan the leftover transforms (cldrest): */ + { + int id = ivs * (nbuf * (vl / nbuf)); + int od = ovs * (nbuf * (vl / nbuf)); + cldrest = X(mkplan_d)(plnr, + X(mkproblem_dft_d)( + X(tensor_copy)(p->sz), + X(mktensor_1d)(vl % nbuf, ivs, ovs), + p->ri+id, p->ii+id, p->ro+od, p->io+od)); + } + if (!cldrest) + goto nada; + + pln = MKPLAN_DFT(P, &padt, apply); + pln->cld = cld; + pln->cldcpy = cldcpy; + pln->cldrest = cldrest; + pln->slv = ego; + pln->n = n; + pln->vl = vl; + pln->ivs = ivs * nbuf; + pln->ovs = ovs * nbuf; + pln->roffset = roffset; + pln->ioffset = ioffset; + + pln->nbuf = nbuf; + pln->bufdist = bufdist; + + { + opcnt t; + X(ops_add)(&cld->ops, &cldcpy->ops, &t); + X(ops_madd)(vl / nbuf, &t, &cldrest->ops, &pln->super.super.ops); + } + + return &(pln->super.super); + + nada: + X(ifree0)(bufs); + X(plan_destroy_internal)(cldrest); + X(plan_destroy_internal)(cldcpy); + X(plan_destroy_internal)(cld); + return (plan *) 0; +} + +static solver *mksolver(const bufadt *adt) +{ + static const solver_adt sadt = { mkplan }; + S *slv = MKSOLVER(S, &sadt); + slv->adt = adt; + return &(slv->super); +} + + +void X(dft_buffered_register)(planner *p) +{ + /* FIXME: what are good defaults? */ + static const bufadt adt = { + /* nbuf */ 8, + /* maxbufsz */ (65536 / sizeof(R)), + /* skew_alignment */ 8, +#if HAVE_SIMD /* 5 is odd and screws up the alignment. */ + /* skew */ 6, +#else + /* skew */ 5, +#endif + /* nam */ "dft-buffered" + }; + + REGISTER_SOLVER(p, mksolver(&adt)); +} |