diff src/fftw-3.3.8/dft/rank-geq2.c @ 167:bd3cc4d1df30

Add FFTW 3.3.8 source, and a Linux build

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/fftw-3.3.8/dft/rank-geq2.c	Tue Nov 19 14:52:55 2019 +0000
@@ -0,0 +1,202 @@
+/*
+ * Copyright (c) 2003, 2007-14 Matteo Frigo
+ * Copyright (c) 2003, 2007-14 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., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ *
+ */
+
+
+/* plans for DFT of rank >= 2 (multidimensional) */
+
+#include "dft/dft.h"
+
+typedef struct {
+     solver super;
+     int spltrnk;
+     const int *buddies;
+     size_t nbuddies;
+} S;
+
+typedef struct {
+     plan_dft super;
+
+     plan *cld1, *cld2;
+     const S *solver;
+} P;
+
+/* Compute multi-dimensional DFT by applying the two cld plans
+   (lower-rnk DFTs). */
+static void apply(const plan *ego_, R *ri, R *ii, R *ro, R *io)
+{
+     const P *ego = (const P *) ego_;
+     plan_dft *cld1, *cld2;
+
+     cld1 = (plan_dft *) ego->cld1;
+     cld1->apply(ego->cld1, ri, ii, ro, io);
+
+     cld2 = (plan_dft *) ego->cld2;
+     cld2->apply(ego->cld2, ro, io, ro, io);
+}
+
+
+static void awake(plan *ego_, enum wakefulness wakefulness)
+{
+     P *ego = (P *) ego_;
+     X(plan_awake)(ego->cld1, wakefulness);
+     X(plan_awake)(ego->cld2, wakefulness);
+}
+
+static void destroy(plan *ego_)
+{
+     P *ego = (P *) ego_;
+     X(plan_destroy_internal)(ego->cld2);
+     X(plan_destroy_internal)(ego->cld1);
+}
+
+static void print(const plan *ego_, printer *p)
+{
+     const P *ego = (const P *) ego_;
+     const S *s = ego->solver;
+     p->print(p, "(dft-rank>=2/%d%(%p%)%(%p%))",
+	      s->spltrnk, ego->cld1, ego->cld2);
+}
+
+static int picksplit(const S *ego, const tensor *sz, int *rp)
+{
+     A(sz->rnk > 1); /* cannot split rnk <= 1 */
+     if (!X(pickdim)(ego->spltrnk, ego->buddies, ego->nbuddies, sz, 1, rp))
+	  return 0;
+     *rp += 1; /* convert from dim. index to rank */
+     if (*rp >= sz->rnk) /* split must reduce rank */
+	  return 0;
+     return 1;
+}
+
+static int applicable0(const solver *ego_, const problem *p_, int *rp)
+{
+     const problem_dft *p = (const problem_dft *) p_;
+     const S *ego = (const S *)ego_;
+     return (1
+	     && FINITE_RNK(p->sz->rnk) && FINITE_RNK(p->vecsz->rnk)
+	     && p->sz->rnk >= 2
+	     && picksplit(ego, p->sz, rp)
+	  );
+}
+
+/* TODO: revise this. */
+static int applicable(const solver *ego_, const problem *p_, 
+		      const planner *plnr, int *rp)
+{
+     const S *ego = (const S *)ego_;
+     const problem_dft *p = (const problem_dft *) p_;
+
+     if (!applicable0(ego_, p_, rp)) return 0;
+
+     if (NO_RANK_SPLITSP(plnr) && (ego->spltrnk != ego->buddies[0])) return 0;
+
+     /* Heuristic: if the vector stride is greater than the transform
+        sz, don't use (prefer to do the vector loop first with a
+        vrank-geq1 plan). */
+     if (NO_UGLYP(plnr))
+	  if (p->vecsz->rnk > 0 &&
+	      X(tensor_min_stride)(p->vecsz) > X(tensor_max_index)(p->sz))
+	       return 0;
+
+     return 1;
+}
+
+static plan *mkplan(const solver *ego_, const problem *p_, planner *plnr)
+{
+     const S *ego = (const S *) ego_;
+     const problem_dft *p;
+     P *pln;
+     plan *cld1 = 0, *cld2 = 0;
+     tensor *sz1, *sz2, *vecszi, *sz2i;
+     int spltrnk;
+
+     static const plan_adt padt = {
+	  X(dft_solve), awake, print, destroy
+     };
+
+     if (!applicable(ego_, p_, plnr, &spltrnk))
+          return (plan *) 0;
+
+     p = (const problem_dft *) p_;
+     X(tensor_split)(p->sz, &sz1, spltrnk, &sz2);
+     vecszi = X(tensor_copy_inplace)(p->vecsz, INPLACE_OS);
+     sz2i = X(tensor_copy_inplace)(sz2, INPLACE_OS);
+
+     cld1 = X(mkplan_d)(plnr, 
+			X(mkproblem_dft_d)(X(tensor_copy)(sz2),
+					   X(tensor_append)(p->vecsz, sz1),
+					   p->ri, p->ii, p->ro, p->io));
+     if (!cld1) goto nada;
+
+     cld2 = X(mkplan_d)(plnr, 
+			X(mkproblem_dft_d)(
+			     X(tensor_copy_inplace)(sz1, INPLACE_OS),
+			     X(tensor_append)(vecszi, sz2i),
+			     p->ro, p->io, p->ro, p->io));
+     if (!cld2) goto nada;
+
+     pln = MKPLAN_DFT(P, &padt, apply);
+
+     pln->cld1 = cld1;
+     pln->cld2 = cld2;
+
+     pln->solver = ego;
+     X(ops_add)(&cld1->ops, &cld2->ops, &pln->super.super.ops);
+
+     X(tensor_destroy4)(sz1, sz2, vecszi, sz2i);
+
+     return &(pln->super.super);
+
+ nada:
+     X(plan_destroy_internal)(cld2);
+     X(plan_destroy_internal)(cld1);
+     X(tensor_destroy4)(sz1, sz2, vecszi, sz2i);
+     return (plan *) 0;
+}
+
+static solver *mksolver(int spltrnk, const int *buddies, size_t nbuddies)
+{
+     static const solver_adt sadt = { PROBLEM_DFT, mkplan, 0 };
+     S *slv = MKSOLVER(S, &sadt);
+     slv->spltrnk = spltrnk;
+     slv->buddies = buddies;
+     slv->nbuddies = nbuddies;
+     return &(slv->super);
+}
+
+void X(dft_rank_geq2_register)(planner *p)
+{
+     static const int buddies[] = { 1, 0, -2 };
+     size_t i;
+
+     for (i = 0; i < NELEM(buddies); ++i)
+          REGISTER_SOLVER(p, mksolver(buddies[i], buddies, NELEM(buddies)));
+
+     /* FIXME:
+
+        Should we try more buddies? 
+
+        Another possible variant is to swap cld1 and cld2 (or rather,
+        to swap their problems; they are not interchangeable because
+        cld2 must be in-place).  In past versions of FFTW, however, I
+        seem to recall that such rearrangements have made little or no
+        difference.
+     */
+}