--- /dev/null
+/* Copyright (c) 2013-2014. The SimGrid Team.
+ * All rights reserved. */
+
+/* This program is free software; you can redistribute it and/or modify it
+ * under the terms of the license (GNU LGPL) which comes with this package. */
+
+#include "../colls_private.h"
+
+/*****************************************************************************
+
+Copyright (c) 2006, Ahmad Faraj & Xin Yuan,
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:
+
+ * Redistributions of source code must retain the above copyright notice,
+ this list of conditions and the following disclaimer.
+
+ * Redistributions in binary form must reproduce the above copyright notice,
+ this list of conditions and the following disclaimer in the documentation
+ and/or other materials provided with the distribution.
+
+ * Neither the name of the Florida State University nor the names of its
+ contributors may be used to endorse or promote products derived from this
+ software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
+ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+ *************************************************************************
+ * Any results obtained from executing this software require the *
+ * acknowledgment and citation of the software and its owners. *
+ * The full citation is given below: *
+ * *
+ * A. Faraj and X. Yuan. "Automatic Generation and Tuning of MPI *
+ * Collective Communication Routines." The 19th ACM International *
+ * Conference on Supercomputing (ICS), Cambridge, Massachusetts, *
+ * June 20-22, 2005. *
+ *************************************************************************
+
+*****************************************************************************/
+
+/*****************************************************************************
+ * Function: allgather_ring
+ * return: int
+ * inputs:
+ * send_buff: send input buffer
+ * send_count: number of elements to send
+ * send_type: data type of elements being sent
+ * recv_buff: receive output buffer
+ * recv_count: number of elements to received
+ * recv_type: data type of elements being received
+ * comm: communication
+ * Descrp: Function works in P - 1 steps. In step i, node j - i -> j -> j+ i.
+ * Auther: Ahmad Faraj
+ ****************************************************************************/
+int
+smpi_coll_tuned_allgatherv_ring(void *send_buff, int send_count,
+ MPI_Datatype send_type, void *recv_buff,
+ int *recv_counts, int *recv_disps, MPI_Datatype recv_type,
+ MPI_Comm comm)
+{
+
+ MPI_Aint extent;
+ int i, src, dst, rank, num_procs;
+ int tag = COLL_TAG_ALLGATHERV;
+ MPI_Status status;
+
+ char *sendptr = (char *) send_buff;
+ char *recvptr = (char *) recv_buff;
+
+ rank = comm->rank();
+ num_procs = comm->size();
+ extent = send_type->get_extent();
+
+ // local send/recv
+ Request::sendrecv(sendptr, send_count, send_type, rank, tag,
+ recvptr + recv_disps[rank] * extent,
+ recv_counts[rank], recv_type, rank, tag, comm, &status);
+
+ for (i = 1; i < num_procs; i++) {
+ src = (rank - i + num_procs) % num_procs;
+ dst = (rank + i) % num_procs;
+
+ Request::sendrecv(sendptr, send_count, send_type, dst, tag,
+ recvptr + recv_disps[src] * extent, recv_counts[src], recv_type,
+ src, tag, comm, &status);
+ }
+
+ return MPI_SUCCESS;
+}
