Chris@42: /*
Chris@42:  * Copyright (c) 2003, 2007-14 Matteo Frigo
Chris@42:  * Copyright (c) 2003, 2007-14 Massachusetts Institute of Technology
Chris@42:  *
Chris@42:  * This program is free software; you can redistribute it and/or modify
Chris@42:  * it under the terms of the GNU General Public License as published by
Chris@42:  * the Free Software Foundation; either version 2 of the License, or
Chris@42:  * (at your option) any later version.
Chris@42:  *
Chris@42:  * This program is distributed in the hope that it will be useful,
Chris@42:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
Chris@42:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
Chris@42:  * GNU General Public License for more details.
Chris@42:  *
Chris@42:  * You should have received a copy of the GNU General Public License
Chris@42:  * along with this program; if not, write to the Free Software
Chris@42:  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
Chris@42:  *
Chris@42:  */
Chris@42: 
Chris@42: 
Chris@42: 
Chris@42: /* Plans for handling vector transform loops.  These are *just* the
Chris@42:    loops, and rely on child plans for the actual DFTs.
Chris@42:  
Chris@42:    They form a wrapper around solvers that don't have apply functions
Chris@42:    for non-null vectors.
Chris@42:  
Chris@42:    vrank-geq1 plans also recursively handle the case of multi-dimensional
Chris@42:    vectors, obviating the need for most solvers to deal with this.  We
Chris@42:    can also play games here, such as reordering the vector loops.
Chris@42:  
Chris@42:    Each vrank-geq1 plan reduces the vector rank by 1, picking out a
Chris@42:    dimension determined by the vecloop_dim field of the solver. */
Chris@42: 
Chris@42: #include "dft.h"
Chris@42: 
Chris@42: typedef struct {
Chris@42:      solver super;
Chris@42:      int vecloop_dim;
Chris@42:      const int *buddies;
Chris@42:      size_t nbuddies;
Chris@42: } S;
Chris@42: 
Chris@42: typedef struct {
Chris@42:      plan_dft super;
Chris@42: 
Chris@42:      plan *cld;
Chris@42:      INT vl;
Chris@42:      INT ivs, ovs;
Chris@42:      const S *solver;
Chris@42: } P;
Chris@42: 
Chris@42: static void apply(const plan *ego_, R *ri, R *ii, R *ro, R *io)
Chris@42: {
Chris@42:      const P *ego = (const P *) ego_;
Chris@42:      INT i, vl = ego->vl;
Chris@42:      INT ivs = ego->ivs, ovs = ego->ovs;
Chris@42:      dftapply cldapply = ((plan_dft *) ego->cld)->apply;
Chris@42: 
Chris@42:      for (i = 0; i < vl; ++i) {
Chris@42:           cldapply(ego->cld,
Chris@42:                    ri + i * ivs, ii + i * ivs, ro + i * ovs, io + i * ovs);
Chris@42:      }
Chris@42: }
Chris@42: 
Chris@42: static void awake(plan *ego_, enum wakefulness wakefulness)
Chris@42: {
Chris@42:      P *ego = (P *) ego_;
Chris@42:      X(plan_awake)(ego->cld, wakefulness);
Chris@42: }
Chris@42: 
Chris@42: static void destroy(plan *ego_)
Chris@42: {
Chris@42:      P *ego = (P *) ego_;
Chris@42:      X(plan_destroy_internal)(ego->cld);
Chris@42: }
Chris@42: 
Chris@42: static void print(const plan *ego_, printer *p)
Chris@42: {
Chris@42:      const P *ego = (const P *) ego_;
Chris@42:      const S *s = ego->solver;
Chris@42:      p->print(p, "(dft-vrank>=1-x%D/%d%(%p%))",
Chris@42:  	      ego->vl, s->vecloop_dim, ego->cld);
Chris@42: }
Chris@42: 
Chris@42: static int pickdim(const S *ego, const tensor *vecsz, int oop, int *dp)
Chris@42: {
Chris@42:      return X(pickdim)(ego->vecloop_dim, ego->buddies, ego->nbuddies,
Chris@42: 		       vecsz, oop, dp);
Chris@42: }
Chris@42: 
Chris@42: static int applicable0(const solver *ego_, const problem *p_, int *dp)
Chris@42: {
Chris@42:      const S *ego = (const S *) ego_;
Chris@42:      const problem_dft *p = (const problem_dft *) p_;
Chris@42: 
Chris@42:      return (1
Chris@42: 	     && FINITE_RNK(p->vecsz->rnk)
Chris@42: 	     && p->vecsz->rnk > 0
Chris@42: 
Chris@42: 	     /* do not bother looping over rank-0 problems,
Chris@42: 		since they are handled via rdft */
Chris@42: 	     && p->sz->rnk > 0
Chris@42: 
Chris@42: 	     && pickdim(ego, p->vecsz, p->ri != p->ro, dp)
Chris@42: 	  );
Chris@42: }
Chris@42: 
Chris@42: static int applicable(const solver *ego_, const problem *p_, 
Chris@42: 		      const planner *plnr, int *dp)
Chris@42: {
Chris@42:      const S *ego = (const S *)ego_;
Chris@42:      const problem_dft *p;
Chris@42: 
Chris@42:      if (!applicable0(ego_, p_, dp)) return 0;
Chris@42: 
Chris@42:      /* fftw2 behavior */
Chris@42:      if (NO_VRANK_SPLITSP(plnr) && (ego->vecloop_dim != ego->buddies[0]))
Chris@42: 	  return 0;
Chris@42: 
Chris@42:      p = (const problem_dft *) p_;
Chris@42: 
Chris@42:      if (NO_UGLYP(plnr)) {
Chris@42: 	  /* Heuristic: if the transform is multi-dimensional, and the
Chris@42: 	     vector stride is less than the transform size, then we
Chris@42: 	     probably want to use a rank>=2 plan first in order to combine
Chris@42: 	     this vector with the transform-dimension vectors. */
Chris@42: 	  {
Chris@42: 	       iodim *d = p->vecsz->dims + *dp;
Chris@42: 	       if (1
Chris@42: 		   && p->sz->rnk > 1 
Chris@42: 		   && X(imin)(X(iabs)(d->is), X(iabs)(d->os)) 
Chris@42: 		   < X(tensor_max_index)(p->sz)
Chris@42: 		    )
Chris@42: 		    return 0;
Chris@42: 	  }
Chris@42: 
Chris@42: 	  if (NO_NONTHREADEDP(plnr)) return 0; /* prefer threaded version */
Chris@42:      }
Chris@42: 
Chris@42:      return 1;
Chris@42: }
Chris@42: 
Chris@42: static plan *mkplan(const solver *ego_, const problem *p_, planner *plnr)
Chris@42: {
Chris@42:      const S *ego = (const S *) ego_;
Chris@42:      const problem_dft *p;
Chris@42:      P *pln;
Chris@42:      plan *cld;
Chris@42:      int vdim;
Chris@42:      iodim *d;
Chris@42: 
Chris@42:      static const plan_adt padt = {
Chris@42: 	  X(dft_solve), awake, print, destroy
Chris@42:      };
Chris@42: 
Chris@42:      if (!applicable(ego_, p_, plnr, &vdim))
Chris@42:           return (plan *) 0;
Chris@42:      p = (const problem_dft *) p_;
Chris@42: 
Chris@42:      d = p->vecsz->dims + vdim;
Chris@42: 
Chris@42:      A(d->n > 1);
Chris@42:      cld = X(mkplan_d)(plnr,
Chris@42: 		       X(mkproblem_dft_d)(
Chris@42: 			    X(tensor_copy)(p->sz),
Chris@42: 			    X(tensor_copy_except)(p->vecsz, vdim),
Chris@42: 			    TAINT(p->ri, d->is), TAINT(p->ii, d->is),
Chris@42: 			    TAINT(p->ro, d->os), TAINT(p->io, d->os)));
Chris@42:      if (!cld) return (plan *) 0;
Chris@42: 
Chris@42:      pln = MKPLAN_DFT(P, &padt, apply);
Chris@42: 
Chris@42:      pln->cld = cld;
Chris@42:      pln->vl = d->n;
Chris@42:      pln->ivs = d->is;
Chris@42:      pln->ovs = d->os;
Chris@42: 
Chris@42:      pln->solver = ego;
Chris@42:      X(ops_zero)(&pln->super.super.ops);
Chris@42:      pln->super.super.ops.other = 3.14159; /* magic to prefer codelet loops */
Chris@42:      X(ops_madd2)(pln->vl, &cld->ops, &pln->super.super.ops);
Chris@42: 
Chris@42:      if (p->sz->rnk != 1 || (p->sz->dims[0].n > 64))
Chris@42: 	  pln->super.super.pcost = pln->vl * cld->pcost;
Chris@42: 
Chris@42:      return &(pln->super.super);
Chris@42: }
Chris@42: 
Chris@42: static solver *mksolver(int vecloop_dim, const int *buddies, size_t nbuddies)
Chris@42: {
Chris@42:      static const solver_adt sadt = { PROBLEM_DFT, mkplan, 0 };
Chris@42:      S *slv = MKSOLVER(S, &sadt);
Chris@42:      slv->vecloop_dim = vecloop_dim;
Chris@42:      slv->buddies = buddies;
Chris@42:      slv->nbuddies = nbuddies;
Chris@42:      return &(slv->super);
Chris@42: }
Chris@42: 
Chris@42: void X(dft_vrank_geq1_register)(planner *p)
Chris@42: {
Chris@42:      /* FIXME: Should we try other vecloop_dim values? */
Chris@42:      static const int buddies[] = { 1, -1 };
Chris@42:      size_t i;
Chris@42:      
Chris@42:      for (i = 0; i < NELEM(buddies); ++i)
Chris@42:           REGISTER_SOLVER(p, mksolver(buddies[i], buddies, NELEM(buddies)));
Chris@42: }