Added icetCommAlltoall collective communication function.

Changes.txt

@@ -100,3 +100,6 @@ ICET_MAX_IMAGE_SPLIT environment variable, cmake variable, state variable
 All the matrix math helpers icetMatrix* in IceTDevMatrix.h
 
 Const versions of icetImageGetColor* and icetImageGetDepth* functions.
+
+Added Alltoall to communicator.  (Search for Allgather for places to add in
+documentation.)

src/communication/mpi.c

@@ -66,6 +66,11 @@ static void Allgather(IceTCommunicator self,
                       int sendcount,
                       IceTEnum datatype,
                       void *recvbuf);
+static void Alltoall(IceTCommunicator self,
+                     const void *sendbuf,
+                     int sendcount,
+                     IceTEnum datatype,
+                     void *recvbuf);
 static IceTCommRequest Isend(IceTCommunicator self,
                              const void *buf,
                              int count,
@@ -196,6 +201,7 @@ IceTCommunicator icetCreateMPICommunicator(MPI_Comm mpi_comm)
     comm->Gather = Gather;
     comm->Gatherv = Gatherv;
     comm->Allgather = Allgather;
+    comm->Alltoall = Alltoall;
     comm->Isend = Isend;
     comm->Irecv = Irecv;
     comm->Wait = Waitone;
@@ -365,6 +371,20 @@ static void Allgather(IceTCommunicator self,
                   MPI_COMM);
 }
 
+static void Alltoall(IceTCommunicator self,
+                     const void *sendbuf,
+                     int sendcount,
+                     IceTEnum datatype,
+                     void *recvbuf)
+{
+    MPI_Datatype mpitype;
+    CONVERT_DATATYPE(datatype, mpitype);
+
+    MPI_Alltoall((void *)sendbuf, sendcount, mpitype,
+                 recvbuf, sendcount, mpitype,
+                 MPI_COMM);
+}
+
 static IceTCommRequest Isend(IceTCommunicator self,
                              const void *buf,
                              int count,

src/ice-t/communication.c

@@ -158,6 +158,17 @@ void icetCommAllgather(const void *sendbuf,
     comm->Allgather(comm, sendbuf, (int)sendcount, datatype, recvbuf);
 }
 
+void icetCommAlltoall(const void *sendbuf,
+                      IceTSizeType sendcount,
+                      IceTEnum datatype,
+                      void *recvbuf)
+{
+    IceTCommunicator comm = icetGetCommunicator();
+    icetCommCheckCount(sendcount);
+    icetAddSent(sendcount, datatype);
+    comm->Alltoall(comm, sendbuf, (int)sendcount, datatype, recvbuf);
+}
+
 IceTCommRequest icetCommIsend(const void *buf,
                               IceTSizeType count,
                               IceTEnum datatype,

src/include/IceT.h

@@ -94,6 +94,11 @@ struct IceTCommunicatorStruct {
                       int sendcount,
                       IceTEnum datatype,
                       void *recvbuf);
+    void (*Alltoall)(struct IceTCommunicatorStruct *self,
+                     const void *sendbuf,
+                     int sendcount,
+                     IceTEnum datatype,
+                     void *recvbuf);
 
     IceTCommRequest (*Isend)(struct IceTCommunicatorStruct *self,
                              const void *buf,

src/include/IceTDevCommunication.h

@@ -59,6 +59,10 @@ ICET_EXPORT void icetCommAllgather(const void *sendbuf,
                                    IceTSizeType sendcount,
                                    IceTEnum type,
                                    void *recvbuf);
+ICET_EXPORT void icetCommAlltoall(const void *sendbuf,
+                                  IceTSizeType sendcount,
+                                  IceTEnum type,
+                                  void *recvbuf);
 ICET_EXPORT IceTCommRequest icetCommIsend(const void *buf,
                                           IceTSizeType count,
                                           IceTEnum datatype,