diff options
author | scuri <scuri> | 2008-10-17 06:10:15 +0000 |
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committer | scuri <scuri> | 2008-10-17 06:10:15 +0000 |
commit | 5a422aba704c375a307a902bafe658342e209906 (patch) | |
tree | 5005011e086bb863d8fb587ad3319bbec59b2447 /src/fftw3/rdft/rdft2-radix2.c |
First commit - moving from LuaForge to SourceForge
Diffstat (limited to 'src/fftw3/rdft/rdft2-radix2.c')
-rw-r--r-- | src/fftw3/rdft/rdft2-radix2.c | 479 |
1 files changed, 479 insertions, 0 deletions
diff --git a/src/fftw3/rdft/rdft2-radix2.c b/src/fftw3/rdft/rdft2-radix2.c new file mode 100644 index 0000000..280d642 --- /dev/null +++ b/src/fftw3/rdft/rdft2-radix2.c @@ -0,0 +1,479 @@ +/* + * 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: rdft2-radix2.c,v 1.1 2008/10/17 06:11:29 scuri Exp $ */ + +/* + Compute RDFT2 of even size via either a DFT or a vector RDFT of + size n/2. + + This file is meant as a temporary hack until we do the right thing. + + The right thing is: 1) get rid of reduction to DFT, and 2) implement + arbitrary even-radix reduction to RDFT. We currently reduce to DFT + so as to exploit the SIMD code. We currently do only radix-2 in + order to avoid generating yet another set of codelets. +*/ + +#include "rdft.h" +#include "dft.h" + +typedef struct { + int (*applicable) (const problem *p_, const planner *plnr); + void (*apply) (const plan *ego_, R *r, R *rio, R *iio); + problem *(*mkcld) (const problem_rdft2 *p); + opcnt ops; + const char *nam; +} madt; + +typedef struct { + solver super; + const madt *adt; +} S; + +typedef struct { + plan_dft super; + plan *cld; + twid *td; + int is, os, ivs, ovs; + int n, vl; + const S *slv; +} P; + +/* common applicability function of forward problems */ +static int applicable_f(const problem *p_, const planner *plnr) +{ + UNUSED(plnr); + if (RDFT2P(p_)) { + const problem_rdft2 *p = (const problem_rdft2 *) p_; + return (1 + && p->kind == R2HC + && p->vecsz->rnk <= 1 + && p->sz->rnk == 1 + && (p->sz->dims[0].n % 2) == 0 + ); + } + + return 0; +} + +static int applicable_f_dft(const problem *p_, const planner *plnr) +{ + UNUSED(plnr); + if (applicable_f(p_, plnr)) { + const problem_rdft2 *p = (const problem_rdft2 *) p_; + return(p->r != p->rio + || (p->iio == p->rio + p->sz->dims[0].is + && p->sz->dims[0].os == 2 * p->sz->dims[0].is)); + } + return 0; +} + +/* common applicability function of backward problems */ +static int applicable_b(const problem *p_, const planner *plnr) +{ + if (RDFT2P(p_)) { + const problem_rdft2 *p = (const problem_rdft2 *) p_; + return (1 + && p->kind == HC2R + && (p->r == p->rio || DESTROY_INPUTP(plnr)) + && p->vecsz->rnk <= 1 + && p->sz->rnk == 1 + && (p->sz->dims[0].n % 2) == 0 + ); + } + + return 0; +} + +static int applicable_b_dft(const problem *p_, const planner *plnr) +{ + UNUSED(plnr); + if (applicable_b(p_, plnr)) { + const problem_rdft2 *p = (const problem_rdft2 *) p_; + return(p->r != p->rio + || (p->iio == p->rio + p->sz->dims[0].os + && p->sz->dims[0].is == 2 * p->sz->dims[0].os)); + } + return 0; +} + +/* + * forward rdft2 via dft + */ +static void k_f_dft(R *rio, R *iio, const R *W, int n, int dist) +{ + int i; + R *pp = rio, *pm = rio + n * dist; + int im = iio - rio; + + /* i = 0 and i = n */ + { + E rop = pp[0], iop = pp[im]; + pp[0] = rop + iop; + pm[0] = rop - iop; + pp[im] = K(0.0); + pm[im] = K(0.0); + pp += dist; pm -= dist; + } + + /* middle elements */ + for (W += 2, i = 2; i < n; i += 2, W += 2) { + E rop = pp[0], iop = pp[im], rom = pm[0], iom = pm[im]; + E wr = W[0], wi = W[1]; + E re = rop + rom; + E ie = iop - iom; + E rd = rom - rop; + E id = iop + iom; + E tr = rd * wr - id * wi; + E ti = id * wr + rd * wi; + pp[0] = K(0.5) * (re + ti); + pp[im] = K(0.5) * (ie + tr); + pm[0] = K(0.5) * (re - ti); + pm[im] = K(0.5) * (tr - ie); + pp += dist; pm -= dist; + } + + /* i = n/2 when n is even */ + if (!(n & 1)) pp[im] = -pp[im]; +} + +static void apply_f_dft(const plan *ego_, R *r, R *rio, R *iio) +{ + const P *ego = (const P *) ego_; + + { + /* transform input as a vector of complex numbers */ + plan_dft *cld = (plan_dft *) ego->cld; + cld->apply((plan *) cld, r, r + ego->is, rio, iio); + } + + { + int i, vl = ego->vl, n2 = ego->n / 2; + int ovs = ego->ovs, os = ego->os; + const R *W = ego->td->W; + for (i = 0; i < vl; ++i, rio += ovs, iio += ovs) + k_f_dft(rio, iio, W, n2, os); + } +} + +static problem *mkcld_f_dft(const problem_rdft2 *p) +{ + const iodim *d = p->sz->dims; + return X(mkproblem_dft_d) ( + X(mktensor_1d)(d[0].n / 2, d[0].is * 2, d[0].os), + X(tensor_copy)(p->vecsz), + p->r, p->r + d[0].is, p->rio, p->iio); +} + +static const madt adt_f_dft = { + applicable_f_dft, apply_f_dft, mkcld_f_dft, {10, 8, 0, 0}, "r2hc2-dft" +}; + +/* + * forward rdft2 via rdft + */ +static void k_f_rdft(R *rio, R *iio, const R *W, int n, int dist) +{ + int i; + R *pp = rio, *pm = rio + n * dist; + int im = iio - rio; + + /* i = 0 and i = n */ + { + E rop = pp[0], iop = pp[im]; + pp[0] = rop + iop; + pm[0] = rop - iop; + pp[im] = K(0.0); + pm[im] = K(0.0); + pp += dist; pm -= dist; + } + + /* middle elements */ + for (W += 2, i = 2; i < n; i += 2, W += 2) { + E r0 = pp[0], r1 = pp[im], i0 = pm[0], i1 = pm[im]; + E wr = W[0], wi = W[1]; + E tr = r1 * wr + i1 * wi; + E ti = i1 * wr - r1 * wi; + pp[0] = r0 + tr; + pp[im] = i0 + ti; + pm[0] = r0 - tr; + pm[im] = ti - i0; + pp += dist; pm -= dist; + } + + /* i = n/2 when n is even */ + if (!(n & 1)) pp[im] = -pp[im]; +} + +static void apply_f_rdft(const plan *ego_, R *r, R *rio, R *iio) +{ + const P *ego = (const P *) ego_; + + { + plan_rdft *cld = (plan_rdft *) ego->cld; + cld->apply((plan *) cld, r, rio); + } + + { + int i, vl = ego->vl, n2 = ego->n / 2; + int ovs = ego->ovs, os = ego->os; + const R *W = ego->td->W; + for (i = 0; i < vl; ++i, rio += ovs, iio += ovs) + k_f_rdft(rio, iio, W, n2, os); + } +} + +static problem *mkcld_f_rdft(const problem_rdft2 *p) +{ + const iodim *d = p->sz->dims; + + tensor *radix = X(mktensor_1d)(2, d[0].is, p->iio - p->rio); + tensor *cld_vec = X(tensor_append)(radix, p->vecsz); + X(tensor_destroy)(radix); + + return X(mkproblem_rdft_1_d) ( + X(mktensor_1d)(d[0].n / 2, 2 * d[0].is, d[0].os), + cld_vec, p->r, p->rio, R2HC); +} + +static const madt adt_f_rdft = { + applicable_f, apply_f_rdft, mkcld_f_rdft, {6, 4, 0, 0}, "r2hc2-rdft" +}; + + +/* + * backward rdft2 via dft + */ +static void k_b_dft(R *rio, R *iio, const R *W, int n, int dist) +{ + int i; + R *pp = rio, *pm = rio + n * dist; + int im = iio - rio; + + /* i = 0 and i = n */ + { + E rop = pp[0], iop = pm[0]; + pp[0] = rop + iop; + pp[im] = rop - iop; + pp += dist; pm -= dist; + } + + /* middle elements */ + for (W += 2, i = 2; i < n; i += 2, W += 2) { + E a = pp[0], b = pp[im], c = pm[0], d = pm[im]; + E wr = W[0], wi = W[1]; + E re = a + c, ti = a - c, ie = b - d, tr = b + d; + E rd = tr * wr + ti * wi; + E id = ti * wr - tr * wi; + pp[0] = re - rd; + pp[im] = ie + id; + pm[0] = re + rd; + pm[im] = id - ie; + pp += dist; pm -= dist; + } + + /* i = n/2 when n is even */ + if (!(n & 1)) { pp[0] *= K(2.0); pp[im] *= -K(2.0); } +} + +static void apply_b_dft(const plan *ego_, R *r, R *rio, R *iio) +{ + const P *ego = (const P *) ego_; + { + int i, vl = ego->vl, n2 = ego->n / 2; + int ivs = ego->ivs, is = ego->is; + const R *W = ego->td->W; + R *rio1 = rio, *iio1 = iio; + for (i = 0; i < vl; ++i, rio1 += ivs, iio1 += ivs) + k_b_dft(rio1, iio1, W, n2, is); + } + + { + plan_dft *cld = (plan_dft *) ego->cld; + /* swap r/i because of backward transform */ + cld->apply((plan *) cld, iio, rio, r + ego->os, r); + } +} + +static problem *mkcld_b_dft(const problem_rdft2 *p) +{ + const iodim *d = p->sz->dims; + + return X(mkproblem_dft_d) ( + X(mktensor_1d)(d[0].n / 2, d[0].is, 2 * d[0].os), + X(tensor_copy)(p->vecsz), + p->iio, p->rio, p->r + d[0].os, p->r); +} + +static const madt adt_b_dft = { + applicable_b_dft, apply_b_dft, mkcld_b_dft, {10, 8, 0, 0}, "hc2r2-dft" +}; + +/* + * backward rdft2 via backward rdft + */ +static void k_b_rdft(R *rio, R *iio, const R *W, int n, int dist) +{ + int i; + R *pp = rio, *pm = rio + n * dist; + int im = iio - rio; + + /* i = 0 and i = n */ + { + E rop = pp[0], iop = pm[0]; + pp[0] = rop + iop; + pp[im] = rop - iop; + pp += dist; pm -= dist; + } + + /* middle elements */ + for (W += 2, i = 2; i < n; i += 2, W += 2) { + E a = pp[0], b = pp[im], c = pm[0], d = pm[im]; + E wr = W[0], wi = W[1]; + E r0 = a + c, r1 = a - c, i0 = b - d, i1 = b + d; + pp[0] = r0; + pm[0] = i0; + pp[im] = r1 * wr - i1 * wi; + pm[im] = i1 * wr + r1 * wi; + pp += dist; pm -= dist; + } + + /* i = n/2 when n is even */ + if (!(n & 1)) { pp[0] *= K(2.0); pp[im] *= -K(2.0); } +} + +static void apply_b_rdft(const plan *ego_, R *r, R *rio, R *iio) +{ + const P *ego = (const P *) ego_; + + { + int i, vl = ego->vl, n2 = ego->n / 2; + int ivs = ego->ivs, is = ego->is; + const R *W = ego->td->W; + R *rio1 = rio, *iio1 = iio; + for (i = 0; i < vl; ++i, rio1 += ivs, iio1 += ivs) + k_b_rdft(rio1, iio1, W, n2, is); + } + + { + plan_rdft *cld = (plan_rdft *) ego->cld; + cld->apply((plan *) cld, rio, r); + } +} + +static problem *mkcld_b_rdft(const problem_rdft2 *p) +{ + const iodim *d = p->sz->dims; + + tensor *radix = X(mktensor_1d)(2, p->iio - p->rio, d[0].os); + tensor *cld_vec = X(tensor_append)(radix, p->vecsz); + X(tensor_destroy)(radix); + + return X(mkproblem_rdft_1_d) ( + X(mktensor_1d)(d[0].n / 2, d[0].is, 2 * d[0].os), + cld_vec, p->rio, p->r, HC2R); +} + +static const madt adt_b_rdft = { + applicable_b, apply_b_rdft, mkcld_b_rdft, {6, 4, 0, 0}, "hc2r2-rdft" +}; + +/* + * common stuff + */ +static void awake(plan *ego_, int flg) +{ + P *ego = (P *) ego_; + static const tw_instr twinstr[] = { {TW_FULL, 0, 2}, {TW_NEXT, 1, 0} }; + AWAKE(ego->cld, flg); + X(twiddle_awake)(flg, &ego->td, twinstr, ego->n, 2, (ego->n / 2 + 1) / 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, "(%s-%d%v%(%p%))", ego->slv->adt->nam, + ego->n, ego->vl, ego->cld); +} + +static plan *mkplan(const solver *ego_, const problem *p_, planner *plnr) +{ + const S *ego = (const S *) ego_; + P *pln; + const problem_rdft2 *p; + plan *cld; + const iodim *d; + + static const plan_adt padt = { + X(rdft2_solve), awake, print, destroy + }; + + if (!ego->adt->applicable(p_, plnr)) + return (plan *) 0; + + p = (const problem_rdft2 *) p_; + + cld = X(mkplan_d)(plnr, ego->adt->mkcld(p)); + if (!cld) return (plan *) 0; + + pln = MKPLAN_RDFT2(P, &padt, ego->adt->apply); + + d = p->sz->dims; + pln->n = d[0].n; + pln->os = d[0].os; + pln->is = d[0].is; + X(tensor_tornk1) (p->vecsz, &pln->vl, &pln->ivs, &pln->ovs); + pln->cld = cld; + pln->td = 0; + pln->slv = ego; + + /* approximately */ + X(ops_madd)(pln->vl * ((pln->n/2 + 1) / 2), &ego->adt->ops, + &cld->ops, &pln->super.super.ops); + + return &(pln->super.super); +} + +static solver *mksolver(const madt *adt) +{ + static const solver_adt sadt = { mkplan }; + S *slv = MKSOLVER(S, &sadt); + slv->adt = adt; + return &(slv->super); +} + +void X(rdft2_radix2_register)(planner *p) +{ + unsigned i; + static const madt *const adts[] = { + &adt_f_dft, &adt_f_rdft, + &adt_b_dft, &adt_b_rdft + }; + + for (i = 0; i < sizeof(adts) / sizeof(adts[0]); ++i) + REGISTER_SOLVER(p, mksolver(adts[i])); +} |