Imported from /home/lorry/working-area/delta_boost-tarball/boost_1_54_0.tar.bz2.boost_1_54_0baserock/morph

1 files changed, 98 insertions, 0 deletions

diff --git a/libs/mpi/src/point_to_point.cpp b/libs/mpi/src/point_to_point.cpp
new file mode 100644
index 000000000..dd0d9bcf0
--- /dev/null
+++ b/libs/mpi/src/point_to_point.cpp
@@ -0,0 +1,98 @@
+// Copyright 2005 Douglas Gregor.
+
+// Use, modification and distribution is subject to the Boost Software
+// License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
+// http://www.boost.org/LICENSE_1_0.txt)
+
+// Message Passing Interface 1.1 -- Section 3. MPI Point-to-point
+
+/* There is the potential for optimization here. We could keep around
+   a "small message" buffer of size N that we just receive into by
+   default. If the message is N - sizeof(int) bytes or smaller, it can
+   just be sent with that buffer. If it's larger, we send the first N
+   - sizeof(int) bytes in the first packet followed by another
+   packet. The size of the second packet will be stored in an integer
+   at the end of the first packet.
+
+   We will introduce this optimization later, when we have more
+   performance test cases and have met our functionality goals. */
+
+#include <boost/mpi/detail/point_to_point.hpp>
+#include <boost/mpi/datatype.hpp>
+#include <boost/mpi/exception.hpp>
+#include <cassert>
+
+namespace boost { namespace mpi { namespace detail {
+
+void
+packed_archive_send(MPI_Comm comm, int dest, int tag,
+                    const packed_oarchive& ar)
+{
+  const void* size = &ar.size();
+  BOOST_MPI_CHECK_RESULT(MPI_Send,
+                         (const_cast<void*>(size), 1, 
+                          get_mpi_datatype<std::size_t>(ar.size()), 
+                          dest, tag, comm));
+  BOOST_MPI_CHECK_RESULT(MPI_Send,
+                         (const_cast<void*>(ar.address()), ar.size(),
+                          MPI_PACKED,
+                          dest, tag, comm));
+}
+
+int
+packed_archive_isend(MPI_Comm comm, int dest, int tag,
+                     const packed_oarchive& ar,
+                     MPI_Request* out_requests, int num_out_requests)
+{
+  assert(num_out_requests >= 2);
+  const void* size = &ar.size();
+  BOOST_MPI_CHECK_RESULT(MPI_Isend,
+                         (const_cast<void*>(size), 1, 
+                          get_mpi_datatype<std::size_t>(ar.size()), 
+                          dest, tag, comm, out_requests));
+  BOOST_MPI_CHECK_RESULT(MPI_Isend,
+                         (const_cast<void*>(ar.address()), ar.size(),
+                          MPI_PACKED,
+                          dest, tag, comm, out_requests + 1));
+
+  return 2;
+}
+
+int
+packed_archive_isend(MPI_Comm comm, int dest, int tag,
+                     const packed_iarchive& ar,
+                     MPI_Request* out_requests, int num_out_requests)
+{
+  assert(num_out_requests >= 2);
+
+  const void* size = &ar.size();
+  BOOST_MPI_CHECK_RESULT(MPI_Isend,
+                         (const_cast<void*>(size), 1, 
+                          get_mpi_datatype<std::size_t>(ar.size()), 
+                          dest, tag, comm, out_requests));
+  BOOST_MPI_CHECK_RESULT(MPI_Isend,
+                         (const_cast<void*>(ar.address()), ar.size(),
+                          MPI_PACKED,
+                          dest, tag, comm, out_requests + 1));
+
+  return 2;
+}
+
+void
+packed_archive_recv(MPI_Comm comm, int source, int tag, packed_iarchive& ar,
+                    MPI_Status& status)
+{
+  std::size_t count;
+  BOOST_MPI_CHECK_RESULT(MPI_Recv,
+                         (&count, 1, get_mpi_datatype<std::size_t>(count),
+                          source, tag, comm, &status));
+
+  // Prepare input buffer and receive the message
+  ar.resize(count);
+  BOOST_MPI_CHECK_RESULT(MPI_Recv,
+                         (ar.address(), ar.size(), MPI_PACKED,
+                          status.MPI_SOURCE, status.MPI_TAG,
+                          comm, &status));
+}
+
+} } } // end namespace boost::mpi::detail