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Diffstat (limited to 'src/fftw3/dft/ct-ditbuf.c')
| -rw-r--r-- | src/fftw3/dft/ct-ditbuf.c | 175 |
1 files changed, 175 insertions, 0 deletions
diff --git a/src/fftw3/dft/ct-ditbuf.c b/src/fftw3/dft/ct-ditbuf.c new file mode 100644 index 0000000..2f7b57f --- /dev/null +++ b/src/fftw3/dft/ct-ditbuf.c @@ -0,0 +1,175 @@ +/* + * 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: ct-ditbuf.c,v 1.1 2008/10/17 06:11:08 scuri Exp $ */ + +/* decimation in time Cooley-Tukey. Codelet operates on + contiguous buffer rather than directly on the output array. */ + +/* FIXME: find a way to use rank-0 transforms for this stuff */ + +#include "dft.h" +#include "ct.h" + +/* + Copy A -> B, where A and B are n0 x n1 complex matrices + such that the (i0, i1) element has index (i0 * s0 + i1 * s1). +*/ +static void cpy(int n0, int n1, + const R *rA, const R *iA, int sa0, int sa1, + R *rB, R *iB, int sb0, int sb1) +{ + int i0, i1; + int ima = iA - rA, imb = iB - rB; + + for (i0 = 0; i0 < n0; ++i0) { + const R *pa; + R *pb; + + pa = rA; rA += sa0; + pb = rB; rB += sb0; + for (i1 = 0; i1 < n1; ++i1) { + R xr = pa[0], xi = pa[ima]; + pb[0] = xr; pb[imb] = xi; + pa += sa1; pb += sb1; + } + } +} + +static const R *doit(kdft_dit k, R *rA, R *iA, const R *W, int ios, int dist, + int r, int batchsz, R *buf, stride bufstride) +{ + cpy(r, batchsz, rA, iA, ios, dist, buf, buf + 1, 2, 2 * r); + W = k(buf, buf + 1, W, bufstride, batchsz, 2 * r); + cpy(r, batchsz, buf, buf + 1, 2, 2 * r, rA, iA, ios, dist); + return W; +} + +#define BATCHSZ 4 /* FIXME: parametrize? */ + +static void apply(const plan *ego_, R *ri, R *ii, R *ro, R *io) +{ + const plan_ct *ego = (const plan_ct *) ego_; + plan *cld0 = ego->cld; + plan_dft *cld = (plan_dft *) cld0; + + /* two-dimensional r x vl sub-transform: */ + cld->apply(cld0, ri, ii, ro, io); + + { + int i, j, m = ego->m, vl = ego->vl, r = ego->r; + int os = ego->os, ovs = ego->ovs, ios = ego->iios; + R *buf; + + STACK_MALLOC(R *, buf, r * BATCHSZ * 2 * sizeof(R)); + + for (i = 0; i < vl; ++i) { + R *rA = ro + i * ovs, *iA = io + i * ovs; + const R *W = ego->td->W; + + for (j = m; j >= BATCHSZ; j -= BATCHSZ) { + W = doit(ego->k.dit, rA, iA, W, ios, os, r, + BATCHSZ, buf, ego->vs); + rA += os * (int)BATCHSZ; + iA += os * (int)BATCHSZ; + } + + /* do remaining j calls, if any */ + if (j > 0) + doit(ego->k.dit, rA, iA, W, ios, os, r, j, buf, ego->vs); + + } + + STACK_FREE(buf); + } +} + +static int applicable0(const solver_ct *ego, const problem *p_, + const planner *plnr) +{ + UNUSED(plnr); + if (X(dft_ct_applicable)(ego, p_)) { + const ct_desc *e = ego->desc; + const problem_dft *p = (const problem_dft *) p_; + iodim *d = p->sz->dims; + int m = d[0].n / e->radix; + return (1 + + /* check both batch size and remainder */ + && (m < BATCHSZ || + (e->genus->okp(e, 0, ((const R *)0)+1, 2, 0, BATCHSZ, + 2 * e->radix, plnr))) + && (e->genus->okp(e, 0, ((const R *)0)+1, 2, 0, m % BATCHSZ, + 2 * e->radix, plnr)) + ); + } + return 0; +} + +static int applicable(const solver_ct *ego, const problem *p_, + const planner *plnr) +{ + const problem_dft *p; + + if (!applicable0(ego, p_, plnr)) return 0; + + p = (const problem_dft *) p_; + + /* emulate fftw2 behavior */ + if (NO_VRECURSEP(plnr) && (p->vecsz->rnk > 0)) return 0; + + if (NO_UGLYP(plnr) && X(ct_uglyp)(512, p->sz->dims[0].n, + ego->desc->radix)) + return 0; + + return 1; +} + + +static void finish(plan_ct *ego) +{ + const ct_desc *d = ego->slv->desc; + ego->iios = ego->m * ego->os; + ego->vs = X(mkstride)(ego->r, 2); + X(ops_madd)(ego->vl * ego->m / d->genus->vl, &d->ops, &ego->cld->ops, + &ego->super.super.ops); + + /* 4 load/stores * N * VL */ + ego->super.super.ops.other += 4 * ego->r * ego->m * ego->vl; +} + +static plan *mkplan(const solver *ego, const problem *p, planner *plnr) +{ + static const ctadt adt = { + sizeof(plan_ct), X(dft_mkcld_dit), finish, applicable, apply + }; + return X(mkplan_dft_ct)((const solver_ct *) ego, p, plnr, &adt); +} + + +solver *X(mksolver_dft_ct_ditbuf)(kdft_dit codelet, const ct_desc *desc) +{ + static const solver_adt sadt = { mkplan }; + static const char name[] = "dft-ditbuf"; + union kct k; + k.dit = codelet; + + return X(mksolver_dft_ct)(k, desc, name, &sadt); +} |