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authorscuri <scuri>2009-08-20 12:35:06 +0000
committerscuri <scuri>2009-08-20 12:35:06 +0000
commit5d735255ddd3cb2f547abd3d03969af3fb7eb04e (patch)
tree8fb66510bc625bb1b08ccb41f1b83fb0f7cb8f19 /src/fftw3/rdft/dht-rader.c
parent35733b87eed86e5228f12fa10c98a3d9d22a6073 (diff)
*** empty log message ***
Diffstat (limited to 'src/fftw3/rdft/dht-rader.c')
-rw-r--r--src/fftw3/rdft/dht-rader.c344
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diff --git a/src/fftw3/rdft/dht-rader.c b/src/fftw3/rdft/dht-rader.c
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--- a/src/fftw3/rdft/dht-rader.c
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@@ -1,344 +0,0 @@
-/*
- * 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
- *
- */
-
-#include "rdft.h"
-
-/*
- * Compute DHTs of prime sizes using Rader's trick: turn them
- * into convolutions of size n - 1, which we then perform via a pair
- * of FFTs. (We can then do prime real FFTs via rdft-dht.c.)
- */
-
-typedef struct {
- solver super;
-} S;
-
-typedef struct {
- plan_rdft super;
-
- plan *cld1, *cld2;
- R *omega;
- int n, g, ginv;
- int is, os;
- plan *cld_omega;
-} P;
-
-static rader_tl *omegas = 0;
-
-/***************************************************************************/
-
-/* If R2HC_ONLY_CONV is 1, we use a trick to perform the convolution
- purely in terms of R2HC transforms, as opposed to R2HC followed by H2RC.
- This requires a few more operations, but allows us to share the same
- plan/codelets for both Rader children. */
-#define R2HC_ONLY_CONV 1
-
-static void apply(const plan *ego_, R *I, R *O)
-{
- const P *ego = (const P *) ego_;
- int r = ego->n;
- int is = ego->is, os;
- int k, gpower, g;
- R *buf, *omega;
- R r0;
-
- buf = (R *) MALLOC(sizeof(R) * (r - 1), BUFFERS);
-
- /* First, permute the input, storing in buf: */
- g = ego->g;
- for (gpower = 1, k = 0; k < r - 1; ++k, gpower = MULMOD(gpower, g, r)) {
- buf[k] = I[gpower * is];
- }
- /* gpower == g^(r-1) mod r == 1 */;
-
- os = ego->os;
-
- /* compute RDFT of buf, storing in output (except DC): */
- {
- plan_rdft *cld = (plan_rdft *) ego->cld1;
- cld->apply((plan *) cld, buf, O + os);
- }
-
- /* set output DC component: */
- O[0] = (r0 = I[0]) + O[os];
-
- /* now, multiply by omega: */
- omega = ego->omega;
-
- O[(0 + 1) * os] *= omega[0];
-#if R2HC_ONLY_CONV
- for (k = 1; k < (r - 1)/2; ++k) {
- E rB, iB, rW, iW, a, b;
- rW = omega[k];
- iW = omega[(r-1) - k];
- rB = O[(k + 1) * os];
- iB = O[((r-1) - k + 1) * os];
- a = rW * rB - iW * iB;
- b = rW * iB + iW * rB;
- O[(k + 1) * os] = a + b;
- O[((r-1) - k + 1) * os] = a - b;
- }
-#else
- for (k = 1; k < (r - 1)/2; ++k) {
- E rB, iB, rW, iW;
- rW = omega[k];
- iW = omega[(r-1) - k];
- rB = O[(k + 1) * os];
- iB = O[((r-1) - k + 1) * os];
- O[(k + 1) * os] = rW * rB - iW * iB;
- O[((r-1) - k + 1) * os] = rW * iB + iW * rB;
- }
-#endif
- /* Nyquist component: */
- O[(k + 1) * os] *= omega[k]; /* k == (r-1)/2, since r-1 is even */
-
- /* this will add input[0] to all of the outputs after the ifft */
- O[os] += r0;
-
- /* inverse FFT: */
- {
- plan_rdft *cld = (plan_rdft *) ego->cld2;
- cld->apply((plan *) cld, O + os, buf);
- }
-
- /* do inverse permutation to unshuffle the output: */
- A(gpower == 1);
-#if R2HC_ONLY_CONV
- O[os] = buf[0];
- gpower = g = ego->ginv;
- for (k = 1; k < (r - 1)/2; ++k, gpower = MULMOD(gpower, g, r)) {
- O[gpower * os] = buf[k] + buf[r - 1 - k];
- }
- O[gpower * os] = buf[k];
- ++k, gpower = MULMOD(gpower, g, r);
- for (; k < r - 1; ++k, gpower = MULMOD(gpower, g, r)) {
- O[gpower * os] = buf[r - 1 - k] - buf[k];
- }
-#else
- g = ego->ginv;
- for (k = 0; k < r - 1; ++k, gpower = MULMOD(gpower, g, r)) {
- O[gpower * os] = buf[k];
- }
-#endif
- A(gpower == 1);
-
- X(ifree)(buf);
-}
-
-static R *mkomega(plan *p_, int n, int ginv)
-{
- plan_rdft *p = (plan_rdft *) p_;
- R *omega;
- int i, gpower;
- trigreal scale;
-
- if ((omega = X(rader_tl_find)(n, n, ginv, omegas)))
- return omega;
-
- omega = (R *)MALLOC(sizeof(R) * (n - 1), TWIDDLES);
-
- scale = n - 1.0; /* normalization for convolution */
-
- for (i = 0, gpower = 1; i < n-1; ++i, gpower = MULMOD(gpower, ginv, n)) {
- omega[i] = (X(cos2pi)(gpower, n) + X(sin2pi)(gpower, n)) / scale;
- }
- A(gpower == 1);
-
- AWAKE(p_, 1);
- p->apply(p_, omega, omega);
- AWAKE(p_, 0);
-
- X(rader_tl_insert)(n, n, ginv, omega, &omegas);
- return omega;
-}
-
-static void free_omega(R *omega)
-{
- X(rader_tl_delete)(omega, &omegas);
-}
-
-/***************************************************************************/
-
-static void awake(plan *ego_, int flg)
-{
- P *ego = (P *) ego_;
-
- AWAKE(ego->cld1, flg);
- AWAKE(ego->cld2, flg);
-
- if (flg) {
- if (!ego->omega)
- ego->omega = mkomega(ego->cld_omega,ego->n,ego->ginv);
- } else {
- free_omega(ego->omega);
- ego->omega = 0;
- }
-}
-
-static void destroy(plan *ego_)
-{
- P *ego = (P *) ego_;
- X(plan_destroy_internal)(ego->cld_omega);
- 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_;
-
- p->print(p, "(dht-rader-%d%ois=%oos=%(%p%)",
- ego->n, ego->is, ego->os, ego->cld1);
- if (ego->cld2 != ego->cld1)
- p->print(p, "%(%p%)", ego->cld2);
- if (ego->cld_omega != ego->cld1 && ego->cld_omega != ego->cld2)
- p->print(p, "%(%p%)", ego->cld_omega);
- p->putchr(p, ')');
-}
-
-static int applicable0(const problem *p_)
-{
- if (RDFTP(p_)) {
- const problem_rdft *p = (const problem_rdft *) p_;
- return (1
- && p->sz->rnk == 1
- && p->vecsz->rnk == 0
- && p->kind[0] == DHT
- && X(is_prime)(p->sz->dims[0].n)
- && p->sz->dims[0].n > 2
- );
- }
-
- return 0;
-}
-
-static int applicable(const solver *ego, const problem *p, const planner *plnr)
-{
- UNUSED(ego);
- return (!NO_UGLYP(plnr) && applicable0(p));
-}
-
-static plan *mkplan(const solver *ego_, const problem *p_, planner *plnr)
-{
- const problem_rdft *p = (const problem_rdft *) p_;
- P *pln;
- int n;
- int is, os;
- plan *cld1 = (plan *) 0;
- plan *cld2 = (plan *) 0;
- plan *cld_omega = (plan *) 0;
- R *buf = (R *) 0;
- R *O;
- problem *cldp;
-
- static const plan_adt padt = {
- X(rdft_solve), awake, print, destroy
- };
-
- if (!applicable(ego_, p_, plnr))
- return (plan *) 0;
-
- n = p->sz->dims[0].n;
- is = p->sz->dims[0].is;
- os = p->sz->dims[0].os;
- O = p->O;
-
- /* initial allocation for the purpose of planning */
- buf = (R *) MALLOC(sizeof(R) * (n - 1), BUFFERS);
-
- cld1 = X(mkplan_d)(plnr,
- X(mkproblem_rdft_1_d)(X(mktensor_1d)(n - 1, 1, os),
- X(mktensor_1d)(1, 0, 0),
- buf,
- O + os,
- R2HC));
- if (!cld1) goto nada;
-
- cldp =
- X(mkproblem_rdft_1_d)(
- X(mktensor_1d)(n - 1, os, 1),
- X(mktensor_1d)(1, 0, 0),
- O + os,
- buf,
-#if R2HC_ONLY_CONV
- R2HC
-#else
- HC2R
-#endif
- );
- if (!(cld2 = X(mkplan_d)(plnr, cldp))) goto nada;
-
-
- /* plan for omega */
- plnr->planner_flags |= ESTIMATE;
- cld_omega = X(mkplan_d)(plnr,
- X(mkproblem_rdft_1_d)(X(mktensor_1d)(n - 1, 1, 1),
- X(mktensor_1d)(1, 0, 0),
- buf, buf, R2HC));
- if (!cld_omega) goto nada;
-
- /* deallocate buffers; let awake() or apply() allocate them for real */
- X(ifree)(buf);
- buf = 0;
-
- pln = MKPLAN_RDFT(P, &padt, apply);
- pln->cld1 = cld1;
- pln->cld2 = cld2;
- pln->cld_omega = cld_omega;
- pln->omega = 0;
- pln->n = n;
- pln->is = is;
- pln->os = os;
- pln->g = X(find_generator)(n);
- pln->ginv = X(power_mod)(pln->g, n - 2, n);
- A(MULMOD(pln->g, pln->ginv, n) == 1);
-
- X(ops_add)(&cld1->ops, &cld2->ops, &pln->super.super.ops);
- pln->super.super.ops.other += (n - 3) * 3 + (n - 2) * 2 + 5;
- pln->super.super.ops.add += (n - 3) * 1;
- pln->super.super.ops.mul += (n - 3) * 2 + 2;
-#if R2HC_ONLY_CONV
- pln->super.super.ops.other += (n - 2) + 4;
- pln->super.super.ops.add += (n - 3) * 1 + (n - 2) * 1;
-#endif
-
- return &(pln->super.super);
-
- nada:
- X(ifree0)(buf);
- X(plan_destroy_internal)(cld_omega);
- X(plan_destroy_internal)(cld2);
- X(plan_destroy_internal)(cld1);
- return 0;
-}
-
-/* constructors */
-
-static solver *mksolver(void)
-{
- static const solver_adt sadt = { mkplan };
- S *slv = MKSOLVER(S, &sadt);
- return &(slv->super);
-}
-
-void X(dht_rader_register)(planner *p)
-{
- REGISTER_SOLVER(p, mksolver());
-}