Changes between Version 22 and Version 23 of MessagePassing

Timestamp:

09/13/13 20:10:20 (13 years ago)

Author:

siegel

Comment:

--

MessagePassing

@@ -60 +60 @@
 
 {{{
+
+// most of this stuff could go in a header file which is included here:
+
 #define MPI_ANY_SOURCE $COMM_ANY_SOURCE
 #define MPI_ANY_TAG $COMM_ANY_TAG
@@ -101 +104 @@
 }
 
-void MPI_Send(int pid, void *buf, int count, MPI_Datatype type, int dest, int tag, MPI_Comm comm) {
+
+// very similar to MPI_Send but takes one extra argument at beginning saying who the sender is:
+void CIVL_Send(int pid, void *buf, int count, MPI_Datatype type, int dest, int tag, MPI_Comm comm) {
   $message m = $message_pack(pid, dest, tag, buf, sizeofDatatype(type)*count);
 
@@ -107 +112 @@
 }
 
-void MPI_Recv(int pid, void *buf, int count, MPI_Datataype type, int source, int tag, MPI_Comm comm, MPI_Status *status) {
-  int size = sizeofDatatype(type)*count;
+// note we could define this function this way but it is more efficient to implement
+// as system function:
+struct $comm_recv_pair $comm_recv($comm comm, int source, int dest, int tag) {
+  struct $comm_recv_pair result;
 
-  when ($comm_probe(*comm, source, pid, tag)) {
+  when ($comm_probe(*comm, source, dest, tag)) {
     int index = $comm_seek(*comm, source, pid, tag);
-    $message m = $comm_get(*comm, source, pid, index);
 
-    *comm = $comm_dequeue(*comm, source, pid, index);
-    status->size = $message_size(m);
-    status->source = $message_source(m);
-    status->dest = $message_dest(m);
-    $message_unpack(m, buf, size); // will throw exception if message too big
+    result.msg = $comm_get(*comm, source, pid, index);
+    result.comm = $comm_dequeue(*comm, source, dest, index);
+    return result;
   }
 }
 
+// similar to MPI_Recv with extra arg at beginning saying who the receiver is:
+void CIVL_Recv(int pid, void *buf, int count, MPI_Datataype type, int source, int tag, MPI_Comm comm, MPI_Status *status) {
+  int size = sizeofDatatype(type)*count;
+  struct $comm_recv_pair pair = $comm_recv(*comm, source, pid, tag);
+  $message m = pair.msg;
+
+  status->size = $message_size(m);
+  status->source = $message_source(m);
+  status->dest = $message_dest(m);
+  $message_unpack(m, buf, size); // will throw exception if message too big
+}
+
+
 void MPI_process(int pid) {
+  // these MPI functions are declared here in the process scope so that they can use the pid
+  // could put these in a separate header file which is included here?
+  void MPI_Send(void *buf, int count, MPI_Datatype type, int dest, int tag, MPI_Comm comm) {
+    CIVL_Send(pid, bug, count, type, dest, tag, comm);
+  }
+  void MPI_Recv(void *buf, int count, MPI_Datataype type, int source, int tag, MPI_Comm comm, MPI_Status *status) {
+    CIVL_Recv(pid, bug, count, type, source, tag, comm, status);
+  }
   ...
   MPI_Comm_init(MPI_COMM_WORLD);