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-rw-r--r--boost/mpi/collectives/scatterv.hpp203
1 files changed, 102 insertions, 101 deletions
diff --git a/boost/mpi/collectives/scatterv.hpp b/boost/mpi/collectives/scatterv.hpp
index 6e6f27002b..57e073c81f 100644
--- a/boost/mpi/collectives/scatterv.hpp
+++ b/boost/mpi/collectives/scatterv.hpp
@@ -8,93 +8,90 @@
#ifndef BOOST_MPI_SCATTERV_HPP
#define BOOST_MPI_SCATTERV_HPP
-#include <boost/mpi/exception.hpp>
-#include <boost/mpi/datatype.hpp>
-#include <vector>
-#include <boost/mpi/packed_oarchive.hpp>
-#include <boost/mpi/packed_iarchive.hpp>
-#include <boost/mpi/detail/point_to_point.hpp>
-#include <boost/mpi/communicator.hpp>
-#include <boost/mpi/environment.hpp>
-#include <boost/assert.hpp>
+#include <boost/scoped_array.hpp>
+#include <boost/mpi/collectives/scatter.hpp>
+#include <boost/mpi/detail/offsets.hpp>
+#include <boost/mpi/detail/antiques.hpp>
namespace boost { namespace mpi {
namespace detail {
- // We're scattering from the root for a type that has an associated MPI
- // datatype, so we'll use MPI_Scatterv to do all of the work.
- template<typename T>
- void
- scatterv_impl(const communicator& comm, const T* in_values, const int* sizes,
- const int* displs, T* out_values, int out_size, int root, mpl::true_)
- {
- MPI_Datatype type = get_mpi_datatype<T>(*in_values);
- BOOST_MPI_CHECK_RESULT(MPI_Scatterv,
- (const_cast<T*>(in_values), const_cast<int*>(sizes),
- const_cast<int*>(displs), type,
- out_values, out_size, type, root, comm));
- }
- // We're scattering from a non-root for a type that has an associated MPI
- // datatype, so we'll use MPI_Scatterv to do all of the work.
- template<typename T>
- void
- scatterv_impl(const communicator& comm, T* out_values, int out_size, int root,
- mpl::true_)
- {
- MPI_Datatype type = get_mpi_datatype<T>(*out_values);
- BOOST_MPI_CHECK_RESULT(MPI_Scatterv,
- (0, 0, 0, type,
- out_values, out_size, type,
- root, comm));
- }
+//////////////////////////////////////////////
+/// Implementation for MPI primitive types ///
+//////////////////////////////////////////////
+
+// We're scattering from the root for a type that has an associated MPI
+// datatype, so we'll use MPI_Scatterv to do all of the work.
+template<typename T>
+void
+scatterv_impl(const communicator& comm, const T* in_values, T* out_values, int out_size,
+ const int* sizes, const int* displs, int root, mpl::true_)
+{
+ assert(!sizes || out_size == sizes[comm.rank()]);
+ assert(bool(sizes) == bool(in_values));
+
+ scoped_array<int> new_offsets_mem(make_offsets(comm, sizes, displs, root));
+ if (new_offsets_mem) displs = new_offsets_mem.get();
+ MPI_Datatype type = get_mpi_datatype<T>(*in_values);
+ BOOST_MPI_CHECK_RESULT(MPI_Scatterv,
+ (const_cast<T*>(in_values), const_cast<int*>(sizes),
+ const_cast<int*>(displs), type,
+ out_values, out_size, type, root, comm));
+}
- // We're scattering from the root for a type that does not have an
- // associated MPI datatype, so we'll need to serialize
- // it. Unfortunately, this means that we cannot use MPI_Scatterv, so
- // we'll just have the root send individual messages to the other
- // processes.
- template<typename T>
- void
- scatterv_impl(const communicator& comm, const T* in_values, const int* sizes,
- const int* displs, T* out_values, int out_size, int root, mpl::false_)
- {
- int tag = environment::collectives_tag();
- int nprocs = comm.size();
-
- for (int dest = 0; dest < nprocs; ++dest) {
- if (dest == root) {
- // Our own values will never be transmitted: just copy them.
- std::copy(in_values + displs[dest],
- in_values + displs[dest] + out_size, out_values);
- } else {
- // Send archive
- packed_oarchive oa(comm);
- for (int i = 0; i < sizes[dest]; ++i)
- oa << in_values[ displs[dest] + i ];
- detail::packed_archive_send(comm, dest, tag, oa);
- }
+// We're scattering from a non-root for a type that has an associated MPI
+// datatype, so we'll use MPI_Scatterv to do all of the work.
+template<typename T>
+void
+scatterv_impl(const communicator& comm, T* out_values, int out_size, int root,
+ mpl::true_ is_mpi_type)
+{
+ scatterv_impl(comm, (T const*)0, out_values, out_size,
+ (const int*)0, (const int*)0, root, is_mpi_type);
+}
+
+//////////////////////////////////////////////////
+/// Implementation for non MPI primitive types ///
+//////////////////////////////////////////////////
+
+// We're scattering from the root for a type that does not have an
+// associated MPI datatype, so we'll need to serialize it.
+template<typename T>
+void
+scatterv_impl(const communicator& comm, const T* in_values, T* out_values, int out_size,
+ int const* sizes, int const* displs, int root, mpl::false_)
+{
+ packed_oarchive::buffer_type sendbuf;
+ bool is_root = comm.rank() == root;
+ int nproc = comm.size();
+ std::vector<int> archsizes;
+ if (is_root) {
+ assert(out_size == sizes[comm.rank()]);
+ archsizes.resize(nproc);
+ std::vector<int> skipped;
+ if (displs) {
+ skipped.resize(nproc);
+ offsets2skipped(sizes, displs, c_data(skipped), nproc);
+ displs = c_data(skipped);
}
+ fill_scatter_sendbuf(comm, in_values, sizes, (int const*)0, sendbuf, archsizes);
}
+ dispatch_scatter_sendbuf(comm, sendbuf, archsizes, (T const*)0, out_values, out_size, root);
+}
+
+// We're scattering to a non-root for a type that does not have an
+// associated MPI datatype. input data not needed.
+// it.
+template<typename T>
+void
+scatterv_impl(const communicator& comm, T* out_values, int n, int root,
+ mpl::false_ isnt_mpi_type)
+{
+ assert(root != comm.rank());
+ scatterv_impl(comm, (T const*)0, out_values, n, (int const*)0, (int const*)0, root, isnt_mpi_type);
+}
- // We're scattering to a non-root for a type that does not have an
- // associated MPI datatype, so we'll need to de-serialize
- // it. Unfortunately, this means that we cannot use MPI_Scatterv, so
- // we'll just have all of the non-root nodes send individual
- // messages to the root.
- template<typename T>
- void
- scatterv_impl(const communicator& comm, T* out_values, int out_size, int root,
- mpl::false_)
- {
- int tag = environment::collectives_tag();
-
- packed_iarchive ia(comm);
- MPI_Status status;
- detail::packed_archive_recv(comm, root, tag, ia, status);
- for (int i = 0; i < out_size; ++i)
- ia >> out_values[i];
- }
} // end namespace detail
template<typename T>
@@ -103,13 +100,9 @@ scatterv(const communicator& comm, const T* in_values,
const std::vector<int>& sizes, const std::vector<int>& displs,
T* out_values, int out_size, int root)
{
- int rank = comm.rank();
- if (rank == root)
- detail::scatterv_impl(comm, in_values, &sizes[0], &displs[0],
- out_values, out_size, root, is_mpi_datatype<T>());
- else
- detail::scatterv_impl(comm, out_values, out_size, root,
- is_mpi_datatype<T>());
+ using detail::c_data;
+ scatterv_impl(comm, in_values, out_values, out_size, c_data(sizes), c_data(displs),
+ root, is_mpi_datatype<T>());
}
template<typename T>
@@ -118,12 +111,9 @@ scatterv(const communicator& comm, const std::vector<T>& in_values,
const std::vector<int>& sizes, const std::vector<int>& displs,
T* out_values, int out_size, int root)
{
- if (comm.rank() == root)
- ::boost::mpi::scatterv(comm, &in_values[0], sizes, displs,
- out_values, out_size, root);
- else
- ::boost::mpi::scatterv(comm, static_cast<const T*>(0), sizes, displs,
- out_values, out_size, root);
+ using detail::c_data;
+ ::boost::mpi::scatterv(comm, c_data(in_values), sizes, displs,
+ out_values, out_size, root);
}
template<typename T>
@@ -141,16 +131,10 @@ void
scatterv(const communicator& comm, const T* in_values,
const std::vector<int>& sizes, T* out_values, int root)
{
- int nprocs = comm.size();
- int myrank = comm.rank();
-
- std::vector<int> displs(nprocs);
- for (int rank = 0, aux = 0; rank < nprocs; ++rank) {
- displs[rank] = aux;
- aux += sizes[rank];
- }
- ::boost::mpi::scatterv(comm, in_values, sizes, displs, out_values,
- sizes[myrank], root);
+ using detail::c_data;
+ detail::scatterv_impl(comm, in_values, out_values, sizes[comm.rank()],
+ c_data(sizes), (int const*)0,
+ root, is_mpi_datatype<T>());
}
template<typename T>
@@ -161,6 +145,23 @@ scatterv(const communicator& comm, const std::vector<T>& in_values,
::boost::mpi::scatterv(comm, &in_values[0], sizes, out_values, root);
}
+template<typename T>
+void
+scatterv(const communicator& comm, const T* in_values,
+ T* out_values, int n, int root)
+{
+ detail::scatterv_impl(comm, in_values, out_values, n, (int const*)0, (int const*)0,
+ root, is_mpi_datatype<T>());
+}
+
+template<typename T>
+void
+scatterv(const communicator& comm, const std::vector<T>& in_values,
+ T* out_values, int out_size, int root)
+{
+ ::boost::mpi::scatterv(comm, &in_values[0], out_values, out_size, root);
+}
+
} } // end namespace boost::mpi
#endif // BOOST_MPI_SCATTERV_HPP