comparison src/fftw-3.3.3/kernel/transpose.c @ 10:37bf6b4a2645

Add FFTW3

+/*
+ * Copyright (c) 2003, 2007-11 Matteo Frigo
+ * Copyright (c) 2003, 2007-11 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
+ *
+ */
+
+#include "ifftw.h"
+
+/* in place square transposition, iterative */
+void X(transpose)(R *I, INT n, INT s0, INT s1, INT vl)
+{
+     INT i0, i1, v;
+
+     switch (vl) {
+	 case 1:
+	      for (i1 = 1; i1 < n; ++i1) {
+		   for (i0 = 0; i0 < i1; ++i0) {
+			R x0 = I[i1 * s0 + i0 * s1];
+			R y0 = I[i1 * s1 + i0 * s0];
+			I[i1 * s1 + i0 * s0] = x0;
+			I[i1 * s0 + i0 * s1] = y0;
+		   }
+	      }
+	      break;
+	 case 2:
+	      for (i1 = 1; i1 < n; ++i1) {
+		   for (i0 = 0; i0 < i1; ++i0) {
+			R x0 = I[i1 * s0 + i0 * s1];
+			R x1 = I[i1 * s0 + i0 * s1 + 1];
+			R y0 = I[i1 * s1 + i0 * s0];
+			R y1 = I[i1 * s1 + i0 * s0 + 1];
+			I[i1 * s1 + i0 * s0] = x0;
+			I[i1 * s1 + i0 * s0 + 1] = x1;
+			I[i1 * s0 + i0 * s1] = y0;
+			I[i1 * s0 + i0 * s1 + 1] = y1;
+		   }
+	      }
+	      break;
+	 default:
+	      for (i1 = 1; i1 < n; ++i1) {
+		   for (i0 = 0; i0 < i1; ++i0) {
+			for (v = 0; v < vl; ++v) {
+			     R x0 = I[i1 * s0 + i0 * s1 + v];
+			     R y0 = I[i1 * s1 + i0 * s0 + v];
+			     I[i1 * s1 + i0 * s0 + v] = x0;
+			     I[i1 * s0 + i0 * s1 + v] = y0;
+			}
+		   }
+	      }
+	      break;
+     }
+}
+
+struct transpose_closure {
+     R *I;
+     INT s0, s1, vl, tilesz;
+     R *buf0, *buf1; 
+};
+
+static void dotile(INT n0l, INT n0u, INT n1l, INT n1u, void *args)
+{
+     struct transpose_closure *k = (struct transpose_closure *)args;
+     R *I = k->I;
+     INT s0 = k->s0, s1 = k->s1, vl = k->vl;
+     INT i0, i1, v;
+
+     switch (vl) {
+	 case 1:
+	      for (i1 = n1l; i1 < n1u; ++i1) {
+		   for (i0 = n0l; i0 < n0u; ++i0) {
+			R x0 = I[i1 * s0 + i0 * s1];
+			R y0 = I[i1 * s1 + i0 * s0];
+			I[i1 * s1 + i0 * s0] = x0;
+			I[i1 * s0 + i0 * s1] = y0;
+		   }
+	      }
+	      break;
+	 case 2:
+	      for (i1 = n1l; i1 < n1u; ++i1) {
+		   for (i0 = n0l; i0 < n0u; ++i0) {
+			R x0 = I[i1 * s0 + i0 * s1];
+			R x1 = I[i1 * s0 + i0 * s1 + 1];
+			R y0 = I[i1 * s1 + i0 * s0];
+			R y1 = I[i1 * s1 + i0 * s0 + 1];
+			I[i1 * s1 + i0 * s0] = x0;
+			I[i1 * s1 + i0 * s0 + 1] = x1;
+			I[i1 * s0 + i0 * s1] = y0;
+			I[i1 * s0 + i0 * s1 + 1] = y1;
+		   }
+	      }
+	      break;
+	 default:
+	      for (i1 = n1l; i1 < n1u; ++i1) {
+		   for (i0 = n0l; i0 < n0u; ++i0) {
+			for (v = 0; v < vl; ++v) {
+			     R x0 = I[i1 * s0 + i0 * s1 + v];
+			     R y0 = I[i1 * s1 + i0 * s0 + v];
+			     I[i1 * s1 + i0 * s0 + v] = x0;
+			     I[i1 * s0 + i0 * s1 + v] = y0;
+			}
+		   }
+	      }
+     }
+}
+
+static void dotile_buf(INT n0l, INT n0u, INT n1l, INT n1u, void *args)
+{
+     struct transpose_closure *k = (struct transpose_closure *)args;
+     X(cpy2d_ci)(k->I + n0l * k->s0 + n1l * k->s1,
+		 k->buf0,
+		 n0u - n0l, k->s0, k->vl,
+		 n1u - n1l, k->s1, k->vl * (n0u - n0l),
+		 k->vl);
+     X(cpy2d_ci)(k->I + n0l * k->s1 + n1l * k->s0,
+		 k->buf1,
+		 n0u - n0l, k->s1, k->vl,
+		 n1u - n1l, k->s0, k->vl * (n0u - n0l),
+		 k->vl);
+     X(cpy2d_co)(k->buf1,
+		 k->I + n0l * k->s0 + n1l * k->s1,
+		 n0u - n0l, k->vl, k->s0,
+		 n1u - n1l, k->vl * (n0u - n0l), k->s1,
+		 k->vl);
+     X(cpy2d_co)(k->buf0,
+		 k->I + n0l * k->s1 + n1l * k->s0,
+		 n0u - n0l, k->vl, k->s1,
+		 n1u - n1l, k->vl * (n0u - n0l), k->s0,
+		 k->vl);
+}
+
+static void transpose_rec(R *I, INT n,
+			  void (*f)(INT n0l, INT n0u, INT n1l, INT n1u,
+				    void *args),
+			  struct transpose_closure *k)
+{
+   tail:
+     if (n > 1) {
+	  INT n2 = n / 2;
+	  k->I = I;
+	  X(tile2d)(0, n2, n2, n, k->tilesz, f, k);
+	  transpose_rec(I, n2, f, k);
+	  I += n2 * (k->s0 + k->s1); n -= n2; goto tail;
+     }
+}
+
+void X(transpose_tiled)(R *I, INT n, INT s0, INT s1, INT vl) 
+{
+     struct transpose_closure k;
+     k.s0 = s0;
+     k.s1 = s1;
+     k.vl = vl;
+     /* two blocks must be in cache, to be swapped */
+     k.tilesz = X(compute_tilesz)(vl, 2);
+     k.buf0 = k.buf1 = 0; /* unused */
+     transpose_rec(I, n, dotile, &k);
+}
+
+void X(transpose_tiledbuf)(R *I, INT n, INT s0, INT s1, INT vl) 
+{
+     struct transpose_closure k;
+     /* Assume that the the rows of I conflict into the same cache
+        lines, and therefore we don't need to reserve cache space for
+        the input.  If the rows don't conflict, there is no reason
+	to use tiledbuf at all.*/
+     R buf0[CACHESIZE / (2 * sizeof(R))];
+     R buf1[CACHESIZE / (2 * sizeof(R))];
+     k.s0 = s0;
+     k.s1 = s1;
+     k.vl = vl;
+     k.tilesz = X(compute_tilesz)(vl, 2);
+     k.buf0 = buf0;
+     k.buf1 = buf1;
+     A(k.tilesz * k.tilesz * vl * sizeof(R) <= sizeof(buf0));
+     A(k.tilesz * k.tilesz * vl * sizeof(R) <= sizeof(buf1));
+     transpose_rec(I, n, dotile_buf, &k);
+}
+