diff src/fftw-3.3.8/dft/direct.c @ 82:d0c2a83c1364

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/direct.c	Tue Nov 19 14:52:55 2019 +0000
@@ -0,0 +1,293 @@
+/*
+ * 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
+ *
+ */
+
+
+/* direct DFT solver, if we have a codelet */
+
+#include "dft/dft.h"
+
+typedef struct {
+     solver super;
+     const kdft_desc *desc;
+     kdft k;
+     int bufferedp;
+} S;
+
+typedef struct {
+     plan_dft super;
+
+     stride is, os, bufstride;
+     INT n, vl, ivs, ovs;
+     kdft k;
+     const S *slv;
+} P;
+
+static void dobatch(const P *ego, R *ri, R *ii, R *ro, R *io, 
+		    R *buf, INT batchsz)
+{
+     X(cpy2d_pair_ci)(ri, ii, buf, buf+1,
+		      ego->n, WS(ego->is, 1), WS(ego->bufstride, 1),
+		      batchsz, ego->ivs, 2);
+     
+     if (IABS(WS(ego->os, 1)) < IABS(ego->ovs)) {
+	  /* transform directly to output */
+	  ego->k(buf, buf+1, ro, io, 
+		 ego->bufstride, ego->os, batchsz, 2, ego->ovs);
+     } else {
+	  /* transform to buffer and copy back */
+	  ego->k(buf, buf+1, buf, buf+1, 
+		 ego->bufstride, ego->bufstride, batchsz, 2, 2);
+	  X(cpy2d_pair_co)(buf, buf+1, ro, io,
+			   ego->n, WS(ego->bufstride, 1), WS(ego->os, 1), 
+			   batchsz, 2, ego->ovs);
+     }
+}
+
+static INT compute_batchsize(INT n)
+{
+     /* round up to multiple of 4 */
+     n += 3;
+     n &= -4;
+
+     return (n + 2);
+}
+
+static void apply_buf(const plan *ego_, R *ri, R *ii, R *ro, R *io)
+{
+     const P *ego = (const P *) ego_;
+     R *buf;
+     INT vl = ego->vl, n = ego->n, batchsz = compute_batchsize(n);
+     INT i;
+     size_t bufsz = n * batchsz * 2 * sizeof(R);
+
+     BUF_ALLOC(R *, buf, bufsz);
+
+     for (i = 0; i < vl - batchsz; i += batchsz) {
+	  dobatch(ego, ri, ii, ro, io, buf, batchsz);
+	  ri += batchsz * ego->ivs; ii += batchsz * ego->ivs;
+	  ro += batchsz * ego->ovs; io += batchsz * ego->ovs;
+     }
+     dobatch(ego, ri, ii, ro, io, buf, vl - i);
+
+     BUF_FREE(buf, bufsz);
+}
+
+static void apply(const plan *ego_, R *ri, R *ii, R *ro, R *io)
+{
+     const P *ego = (const P *) ego_;
+     ASSERT_ALIGNED_DOUBLE;
+     ego->k(ri, ii, ro, io, ego->is, ego->os, ego->vl, ego->ivs, ego->ovs);
+}
+
+static void apply_extra_iter(const plan *ego_, R *ri, R *ii, R *ro, R *io)
+{
+     const P *ego = (const P *) ego_;
+     INT vl = ego->vl;
+
+     ASSERT_ALIGNED_DOUBLE;
+
+     /* for 4-way SIMD when VL is odd: iterate over an
+	even vector length VL, and then execute the last
+	iteration as a 2-vector with vector stride 0. */
+     ego->k(ri, ii, ro, io, ego->is, ego->os, vl - 1, ego->ivs, ego->ovs);
+
+     ego->k(ri + (vl - 1) * ego->ivs, ii + (vl - 1) * ego->ivs,
+	    ro + (vl - 1) * ego->ovs, io + (vl - 1) * ego->ovs,
+	    ego->is, ego->os, 1, 0, 0);
+}
+
+static void destroy(plan *ego_)
+{
+     P *ego = (P *) ego_;
+     X(stride_destroy)(ego->is);
+     X(stride_destroy)(ego->os);
+     X(stride_destroy)(ego->bufstride);
+}
+
+static void print(const plan *ego_, printer *p)
+{
+     const P *ego = (const P *) ego_;
+     const S *s = ego->slv;
+     const kdft_desc *d = s->desc;
+
+     if (ego->slv->bufferedp)
+	  p->print(p, "(dft-directbuf/%D-%D%v \"%s\")", 
+		   compute_batchsize(d->sz), d->sz, ego->vl, d->nam);
+     else
+	  p->print(p, "(dft-direct-%D%v \"%s\")", d->sz, ego->vl, d->nam);
+}
+
+static int applicable_buf(const solver *ego_, const problem *p_,
+			  const planner *plnr)
+{
+     const S *ego = (const S *) ego_;
+     const problem_dft *p = (const problem_dft *) p_;
+     const kdft_desc *d = ego->desc;
+     INT vl;
+     INT ivs, ovs;
+     INT batchsz;
+
+     return (
+	  1
+	  && p->sz->rnk == 1
+	  && p->vecsz->rnk == 1
+	  && p->sz->dims[0].n == d->sz
+
+	  /* check strides etc */
+	  && X(tensor_tornk1)(p->vecsz, &vl, &ivs, &ovs)
+
+	  /* UGLY if IS <= IVS */
+	  && !(NO_UGLYP(plnr) &&
+	       X(iabs)(p->sz->dims[0].is) <= X(iabs)(ivs))
+
+	  && (batchsz = compute_batchsize(d->sz), 1)
+	  && (d->genus->okp(d, 0, ((const R *)0) + 1, p->ro, p->io,
+			    2 * batchsz, p->sz->dims[0].os,
+			    batchsz, 2, ovs, plnr))
+	  && (d->genus->okp(d, 0, ((const R *)0) + 1, p->ro, p->io,
+			    2 * batchsz, p->sz->dims[0].os,
+			    vl % batchsz, 2, ovs, plnr))
+
+
+	  && (0
+	      /* can operate out-of-place */
+	      || p->ri != p->ro
+
+	      /* can operate in-place as long as strides are the same */
+	      || X(tensor_inplace_strides2)(p->sz, p->vecsz)
+
+	      /* can do it if the problem fits in the buffer, no matter
+		 what the strides are */
+	      || vl <= batchsz
+	       )
+	  );
+}
+
+static int applicable(const solver *ego_, const problem *p_,
+		      const planner *plnr, int *extra_iterp)
+{
+     const S *ego = (const S *) ego_;
+     const problem_dft *p = (const problem_dft *) p_;
+     const kdft_desc *d = ego->desc;
+     INT vl;
+     INT ivs, ovs;
+
+     return (
+	  1
+	  && p->sz->rnk == 1
+	  && p->vecsz->rnk <= 1
+	  && p->sz->dims[0].n == d->sz
+
+	  /* check strides etc */
+	  && X(tensor_tornk1)(p->vecsz, &vl, &ivs, &ovs)
+
+	  && ((*extra_iterp = 0,
+	       (d->genus->okp(d, p->ri, p->ii, p->ro, p->io,
+			      p->sz->dims[0].is, p->sz->dims[0].os,
+			      vl, ivs, ovs, plnr)))
+	      ||
+	      (*extra_iterp = 1,
+	       ((d->genus->okp(d, p->ri, p->ii, p->ro, p->io,
+			       p->sz->dims[0].is, p->sz->dims[0].os,
+			       vl - 1, ivs, ovs, plnr))
+		&&
+		(d->genus->okp(d, p->ri, p->ii, p->ro, p->io,
+			       p->sz->dims[0].is, p->sz->dims[0].os,
+			       2, 0, 0, plnr)))))
+
+	  && (0
+	      /* can operate out-of-place */
+	      || p->ri != p->ro
+
+	      /* can always compute one transform */
+	      || vl == 1
+
+	      /* can operate in-place as long as strides are the same */
+	      || X(tensor_inplace_strides2)(p->sz, p->vecsz)
+	       )
+	  );
+}
+
+
+static plan *mkplan(const solver *ego_, const problem *p_, planner *plnr)
+{
+     const S *ego = (const S *) ego_;
+     P *pln;
+     const problem_dft *p;
+     iodim *d;
+     const kdft_desc *e = ego->desc;
+
+     static const plan_adt padt = {
+	  X(dft_solve), X(null_awake), print, destroy
+     };
+
+     UNUSED(plnr);
+
+     if (ego->bufferedp) {
+	  if (!applicable_buf(ego_, p_, plnr))
+	       return (plan *)0;
+	  pln = MKPLAN_DFT(P, &padt, apply_buf);
+     } else {
+	  int extra_iterp = 0;
+	  if (!applicable(ego_, p_, plnr, &extra_iterp))
+	       return (plan *)0;
+	  pln = MKPLAN_DFT(P, &padt, extra_iterp ? apply_extra_iter : apply);
+     }
+
+     p = (const problem_dft *) p_;
+     d = p->sz->dims;
+     pln->k = ego->k;
+     pln->n = d[0].n;
+     pln->is = X(mkstride)(pln->n, d[0].is);
+     pln->os = X(mkstride)(pln->n, d[0].os);
+     pln->bufstride = X(mkstride)(pln->n, 2 * compute_batchsize(pln->n));
+
+     X(tensor_tornk1)(p->vecsz, &pln->vl, &pln->ivs, &pln->ovs);
+     pln->slv = ego;
+
+     X(ops_zero)(&pln->super.super.ops);
+     X(ops_madd2)(pln->vl / e->genus->vl, &e->ops, &pln->super.super.ops);
+
+     if (ego->bufferedp) 
+	  pln->super.super.ops.other += 4 * pln->n * pln->vl;
+
+     pln->super.super.could_prune_now_p = !ego->bufferedp;
+     return &(pln->super.super);
+}
+
+static solver *mksolver(kdft k, const kdft_desc *desc, int bufferedp)
+{
+     static const solver_adt sadt = { PROBLEM_DFT, mkplan, 0 };
+     S *slv = MKSOLVER(S, &sadt);
+     slv->k = k;
+     slv->desc = desc;
+     slv->bufferedp = bufferedp;
+     return &(slv->super);
+}
+
+solver *X(mksolver_dft_direct)(kdft k, const kdft_desc *desc)
+{
+     return mksolver(k, desc, 0);
+}
+
+solver *X(mksolver_dft_directbuf)(kdft k, const kdft_desc *desc)
+{
+     return mksolver(k, desc, 1);
+}