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diff --git a/src/fftw3/reodft/reodft11e-r2hc.c b/src/fftw3/reodft/reodft11e-r2hc.c
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-/*
- * 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: reodft11e-r2hc.c,v 1.1 2008/10/17 06:13:18 scuri Exp $ */
-
-/* Do an R{E,O}DFT11 problem via an R2HC problem, with some
- pre/post-processing ala FFTPACK. Use a trick from:
-
- S. C. Chan and K. L. Ho, "Direct methods for computing discrete
- sinusoidal transforms," IEE Proceedings F 137 (6), 433--442 (1990).
-
- to re-express as an REDFT01 (DCT-III) problem.
-
- NOTE: We no longer use this algorithm, because it turns out to suffer
- a catastrophic loss of accuracy for certain inputs, apparently because
- its post-processing multiplies the output by a cosine. Near the zero
- of the cosine, the REDFT01 must produce a near-singular output.
-*/
-
-#include "reodft.h"
-
-typedef struct {
- solver super;
-} S;
-
-typedef struct {
- plan_rdft super;
- plan *cld;
- twid *td, *td2;
- int is, os;
- int n;
- int vl;
- int ivs, ovs;
- rdft_kind kind;
-} P;
-
-static void apply_re11(const plan *ego_, R *I, R *O)
-{
- const P *ego = (const P *) ego_;
- int is = ego->is, os = ego->os;
- int i, n = ego->n;
- int iv, vl = ego->vl;
- int ivs = ego->ivs, ovs = ego->ovs;
- R *W;
- R *buf;
- E cur;
-
- buf = (R *) MALLOC(sizeof(R) * n, BUFFERS);
-
- for (iv = 0; iv < vl; ++iv, I += ivs, O += ovs) {
- /* I wish that this didn't require an extra pass. */
- /* FIXME: use recursive/cascade summation for better stability? */
- buf[n - 1] = cur = K(2.0) * I[is * (n - 1)];
- for (i = n - 1; i > 0; --i) {
- E curnew;
- buf[(i - 1)] = curnew = K(2.0) * I[is * (i - 1)] - cur;
- cur = curnew;
- }
-
- W = ego->td->W;
- for (i = 1; i < n - i; ++i) {
- E a, b, apb, amb, wa, wb;
- a = buf[i];
- b = buf[n - i];
- apb = a + b;
- amb = a - b;
- wa = W[2*i];
- wb = W[2*i + 1];
- buf[i] = wa * amb + wb * apb;
- buf[n - i] = wa * apb - wb * amb;
- }
- if (i == n - i) {
- buf[i] = K(2.0) * buf[i] * W[2*i];
- }
-
- {
- plan_rdft *cld = (plan_rdft *) ego->cld;
- cld->apply((plan *) cld, buf, buf);
- }
-
- W = ego->td2->W;
- O[0] = W[0] * buf[0];
- for (i = 1; i < n - i; ++i) {
- E a, b;
- int k;
- a = buf[i];
- b = buf[n - i];
- k = i + i;
- O[os * (k - 1)] = W[k - 1] * (a - b);
- O[os * k] = W[k] * (a + b);
- }
- if (i == n - i) {
- O[os * (n - 1)] = W[n - 1] * buf[i];
- }
- }
-
- X(ifree)(buf);
-}
-
-/* like for rodft01, rodft11 is obtained from redft11 by
- reversing the input and flipping the sign of every other output. */
-static void apply_ro11(const plan *ego_, R *I, R *O)
-{
- const P *ego = (const P *) ego_;
- int is = ego->is, os = ego->os;
- int i, n = ego->n;
- int iv, vl = ego->vl;
- int ivs = ego->ivs, ovs = ego->ovs;
- R *W;
- R *buf;
- E cur;
-
- buf = (R *) MALLOC(sizeof(R) * n, BUFFERS);
-
- for (iv = 0; iv < vl; ++iv, I += ivs, O += ovs) {
- /* I wish that this didn't require an extra pass. */
- /* FIXME: use recursive/cascade summation for better stability? */
- buf[n - 1] = cur = K(2.0) * I[0];
- for (i = n - 1; i > 0; --i) {
- E curnew;
- buf[(i - 1)] = curnew = K(2.0) * I[is * (n - i)] - cur;
- cur = curnew;
- }
-
- W = ego->td->W;
- for (i = 1; i < n - i; ++i) {
- E a, b, apb, amb, wa, wb;
- a = buf[i];
- b = buf[n - i];
- apb = a + b;
- amb = a - b;
- wa = W[2*i];
- wb = W[2*i + 1];
- buf[i] = wa * amb + wb * apb;
- buf[n - i] = wa * apb - wb * amb;
- }
- if (i == n - i) {
- buf[i] = K(2.0) * buf[i] * W[2*i];
- }
-
- {
- plan_rdft *cld = (plan_rdft *) ego->cld;
- cld->apply((plan *) cld, buf, buf);
- }
-
- W = ego->td2->W;
- O[0] = W[0] * buf[0];
- for (i = 1; i < n - i; ++i) {
- E a, b;
- int k;
- a = buf[i];
- b = buf[n - i];
- k = i + i;
- O[os * (k - 1)] = W[k - 1] * (b - a);
- O[os * k] = W[k] * (a + b);
- }
- if (i == n - i) {
- O[os * (n - 1)] = -W[n - 1] * buf[i];
- }
- }
-
- X(ifree)(buf);
-}
-
-static void awake(plan *ego_, int flg)
-{
- P *ego = (P *) ego_;
- static const tw_instr reodft010e_tw[] = {
- { TW_COS, 0, 1 },
- { TW_SIN, 0, 1 },
- { TW_NEXT, 1, 0 }
- };
- static const tw_instr reodft11e_tw[] = {
- { TW_COS, 1, 1 },
- { TW_NEXT, 2, 0 }
- };
-
- AWAKE(ego->cld, flg);
-
- X(twiddle_awake)(flg, &ego->td, reodft010e_tw, 4*ego->n, 1, ego->n/2+1);
- X(twiddle_awake)(flg, &ego->td2, reodft11e_tw, 8*ego->n, 1, ego->n * 2);
-}
-
-static void destroy(plan *ego_)
-{
- P *ego = (P *) ego_;
- X(plan_destroy_internal)(ego->cld);
-}
-
-static void print(const plan *ego_, printer *p)
-{
- const P *ego = (const P *) ego_;
- p->print(p, "(%se-r2hc-%d%v%(%p%))",
- X(rdft_kind_str)(ego->kind), ego->n, ego->vl, ego->cld);
-}
-
-static int applicable0(const solver *ego_, const problem *p_)
-{
- UNUSED(ego_);
- if (RDFTP(p_)) {
- const problem_rdft *p = (const problem_rdft *) p_;
- return (1
- && p->sz->rnk == 1
- && p->vecsz->rnk <= 1
- && (p->kind[0] == REDFT11 || p->kind[0] == RODFT11)
- );
- }
-
- return 0;
-}
-
-static int applicable(const solver *ego, const problem *p, const planner *plnr)
-{
- return (!NO_UGLYP(plnr) && applicable0(ego, p));
-}
-
-static plan *mkplan(const solver *ego_, const problem *p_, planner *plnr)
-{
- P *pln;
- const problem_rdft *p;
- plan *cld;
- R *buf;
- int n;
- opcnt ops;
-
- static const plan_adt padt = {
- X(rdft_solve), awake, print, destroy
- };
-
- if (!applicable(ego_, p_, plnr))
- return (plan *)0;
-
- p = (const problem_rdft *) p_;
-
- n = p->sz->dims[0].n;
- buf = (R *) MALLOC(sizeof(R) * n, BUFFERS);
-
- cld = X(mkplan_d)(plnr, X(mkproblem_rdft_1_d)(X(mktensor_1d)(n, 1, 1),
- X(mktensor_0d)(),
- buf, buf, R2HC));
- X(ifree)(buf);
- if (!cld)
- return (plan *)0;
-
- pln = MKPLAN_RDFT(P, &padt, p->kind[0]==REDFT11 ? apply_re11:apply_ro11);
- pln->n = n;
- pln->is = p->sz->dims[0].is;
- pln->os = p->sz->dims[0].os;
- pln->cld = cld;
- pln->td = pln->td2 = 0;
- pln->kind = p->kind[0];
-
- X(tensor_tornk1)(p->vecsz, &pln->vl, &pln->ivs, &pln->ovs);
-
- X(ops_zero)(&ops);
- ops.other = 5 + (n-1) * 2 + (n-1)/2 * 12 + (1 - n % 2) * 6;
- ops.add = (n - 1) * 1 + (n-1)/2 * 6;
- ops.mul = 2 + (n-1) * 1 + (n-1)/2 * 6 + (1 - n % 2) * 3;
-
- X(ops_zero)(&pln->super.super.ops);
- X(ops_madd2)(pln->vl, &ops, &pln->super.super.ops);
- X(ops_madd2)(pln->vl, &cld->ops, &pln->super.super.ops);
-
- return &(pln->super.super);
-}
-
-/* constructor */
-static solver *mksolver(void)
-{
- static const solver_adt sadt = { mkplan };
- S *slv = MKSOLVER(S, &sadt);
- return &(slv->super);
-}
-
-void X(reodft11e_r2hc_register)(planner *p)
-{
- REGISTER_SOLVER(p, mksolver());
-}
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