Explicitly avoid temporary in isend.

boostorg · Oct 26, 2016 · e3b0d08 · e3b0d08
1 parent 8e3e9cd
commit e3b0d08
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Showing 3 changed files with 25 additions and 15 deletions.
diff --git a/include/boost/mpi/detail/binary_buffer_oprimitive.hpp b/include/boost/mpi/detail/binary_buffer_oprimitive.hpp
@@ -47,7 +47,12 @@ class BOOST_MPI_DECL binary_buffer_oprimitive
     {
       return size_ = buffer_.size();
     }
-
+
+    const std::size_t* size_ptr() const
+    {
+      return &size();
+    }
+
     void save_binary(void const *address, std::size_t count)
     {
       save_impl(address,count);

diff --git a/include/boost/mpi/detail/packed_oprimitive.hpp b/include/boost/mpi/detail/packed_oprimitive.hpp
@@ -47,6 +47,11 @@ class BOOST_MPI_DECL packed_oprimitive
       return size_ = buffer_.size();
     }
 
+    const std::size_t* size_ptr() const
+    {
+      return &size();
+    }
+
     void save_binary(void const *address, std::size_t count)
         {
           save_impl(address,MPI_BYTE,count);

diff --git a/src/point_to_point.cpp b/src/point_to_point.cpp
@@ -28,13 +28,13 @@ void
 packed_archive_send(MPI_Comm comm, int dest, int tag,
                     const packed_oarchive& ar)
 {
-  std::size_t size = ar.size();
+  std::size_t const& size = ar.size();
   BOOST_MPI_CHECK_RESULT(MPI_Send,
-                         (static_cast<void*>(&size), 1, 
-                          get_mpi_datatype<std::size_t>(ar.size()), 
+                         (&size, 1, 
+                          get_mpi_datatype(size), 
                           dest, tag, comm));
   BOOST_MPI_CHECK_RESULT(MPI_Send,
-                         (const_cast<void*>(ar.address()), ar.size(),
+                         (const_cast<void*>(ar.address()), size,
                           MPI_PACKED,
                           dest, tag, comm));
 }
@@ -45,13 +45,13 @@ packed_archive_isend(MPI_Comm comm, int dest, int tag,
                      MPI_Request* out_requests, int num_out_requests)
 {
   assert(num_out_requests >= 2);
-  const void* size = &ar.size();
+  std::size_t const& size = ar.size();
   BOOST_MPI_CHECK_RESULT(MPI_Isend,
-                         (const_cast<void*>(size), 1, 
-                          get_mpi_datatype<std::size_t>(ar.size()), 
+                         (&size, 1, 
+                          get_mpi_datatype(size),
                           dest, tag, comm, out_requests));
   BOOST_MPI_CHECK_RESULT(MPI_Isend,
-                         (const_cast<void*>(ar.address()), ar.size(),
+                         (const_cast<void*>(ar.address()), size,
                           MPI_PACKED,
                           dest, tag, comm, out_requests + 1));
 
@@ -65,13 +65,13 @@ packed_archive_isend(MPI_Comm comm, int dest, int tag,
 {
   assert(num_out_requests >= 2);
 
-  const void* size = &ar.size();
+  std::size_t const& size = ar.size();
   BOOST_MPI_CHECK_RESULT(MPI_Isend,
-                         (const_cast<void*>(size), 1, 
-                          get_mpi_datatype<std::size_t>(ar.size()), 
+                         (&size, 1, 
+                          get_mpi_datatype(size), 
                           dest, tag, comm, out_requests));
   BOOST_MPI_CHECK_RESULT(MPI_Isend,
-                         (const_cast<void*>(ar.address()), ar.size(),
+                         (const_cast<void*>(ar.address()), size,
                           MPI_PACKED,
                           dest, tag, comm, out_requests + 1));
 
@@ -84,13 +84,13 @@ packed_archive_recv(MPI_Comm comm, int source, int tag, packed_iarchive& ar,
 {
   std::size_t count;
   BOOST_MPI_CHECK_RESULT(MPI_Recv,
-                         (&count, 1, get_mpi_datatype<std::size_t>(count),
+                         (&count, 1, get_mpi_datatype(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,
+                         (ar.address(), count, MPI_PACKED,
                           status.MPI_SOURCE, status.MPI_TAG,
                           comm, &status));
 }