comparison src/fftw-3.3.5/mpi/rearrange.c @ 42:2cd0e3b3e1fd

Current fftw source

+/*
+ * 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
+ *
+ */
+
+#include "ifftw-mpi.h"
+
+/* common functions for rearrangements of the data for the *-rank1-bigvec
+   solvers */
+
+static int div_mult(INT b, INT a) { 
+     return (a > b && a % b == 0);
+}
+static int div_mult2(INT b, INT a, INT n) { 
+     return (div_mult(b, a) && div_mult(n, b));
+}
+
+int XM(rearrange_applicable)(rearrangement rearrange, 
+			     ddim dim0, INT vn, int n_pes)
+{
+     /* note: it is important that cases other than CONTIG be
+	applicable only when the resulting transpose dimension
+	is divisible by n_pes; otherwise, the allocation size
+	returned by the API will be incorrect */
+     return ((rearrange != DISCONTIG || div_mult(n_pes, vn))
+	     && (rearrange != SQUARE_BEFORE 
+		 || div_mult2(dim0.b[IB], vn, n_pes))
+	     && (rearrange != SQUARE_AFTER
+		 || (dim0.b[IB] != dim0.b[OB]
+		     && div_mult2(dim0.b[OB], vn, n_pes)))
+	     && (rearrange != SQUARE_MIDDLE
+		 || div_mult(dim0.n * n_pes, vn)));
+}
+
+INT XM(rearrange_ny)(rearrangement rearrange, ddim dim0, INT vn, int n_pes)
+{
+     switch (rearrange) {
+	 case CONTIG:
+	      return vn;
+	 case DISCONTIG:
+	      return n_pes;
+	 case SQUARE_BEFORE:
+	      return dim0.b[IB];
+	 case SQUARE_AFTER:
+	      return dim0.b[OB];
+	 case SQUARE_MIDDLE:
+	      return dim0.n * n_pes;
+     }
+     return 0;
+}