Fix issues with the actual spm in order to make it works in distributed

This PR fixes minor issues that were not impacting the library in the shared memory case, but that would have a large impact on the distributed case.

• Add a spmInitDist() function to initialize an spm with a specific communicator (MPI_COMM_WORLD by default)
• Add a function to compute the glob2loc array when needed.

src/spm.c

@@ -899,51 +899,57 @@ spmPrintInfo( const spmatrix_t* spm, FILE *stream )
     flttype = (flttype > 5 || flttype < 0) ? 6 : flttype;
     fmttype = (fmttype > 2 || fmttype < 0) ? 3 : fmttype;
 
-    fprintf( stream,
-             "  Matrix type:  %s\n"
-             "  Arithmetic:   %s\n"
-             "  Format:       %s\n"
-             "  N:            %ld\n"
-             "  nnz:          %ld\n",
-             mtxtypestr[mtxtype],
-             flttypestr[flttype],
-             fmttypestr[fmttype],
-             (long)spm->gN,
-             (long)spm->gnnz );
+    if ( spm->clustnum == 0 ) {
+        fprintf( stream,
+                 "  Matrix type:  %s\n"
+                 "  Arithmetic:   %s\n"
+                 "  Format:       %s\n"
+                 "  N:            %ld\n"
+                 "  nnz:          %ld\n",
+                 mtxtypestr[mtxtype],
+                 flttypestr[flttype],
+                 fmttypestr[fmttype],
+                 (long)spm->gN,
+                 (long)spm->gnnz );
+
+        if ( spm->dof != 1 ) {
+            if ( spm->dof > 1 ) {
+                fprintf( stream,
+                         "  Dof:          %ld\n",
+                         (long)spm->dof );
+            }
+            else {
+                fprintf( stream,
+                         "  Dof:          Variadic\n" );
+            }
 
-    if ( spm->dof != 1 ) {
-        if ( spm->dof > 1 ) {
             fprintf( stream,
-                     "  Dof:          %ld\n",
-                     (long)spm->dof );
+                     "  N expanded:   %ld\n"
+                     "  NNZ expanded: %ld\n",
+                     (long)spm->gNexp, (long)spm->gnnzexp );
         }
-        else {
-            fprintf( stream,
-                     "  Dof:          Variadic\n" );
-        }
-
-        fprintf( stream,
-                 "  N expanded:   %ld\n"
-                 "  NNZ expanded: %ld\n",
-                 (long)spm->gNexp, (long)spm->gnnzexp );
     }
-
     if ( spm->loc2glob ) {
         int c;
-        fprintf( stream,
-                 "  Details:\n"
-                 "        N       nnz       %s\n",
-                 ( spm->dof != 1 ) ? "Nexp    NNZexp     " : "" );
-        for( c=0; c<spm->clustnbr; c++ ) {
+        if ( spm->clustnum == 0 ) {
             fprintf( stream,
-                     "    %2d: %7ld %9ld",
-                     spm->clustnum, (long)spm->n, (long)spm->nnz );
-
-            if ( spm->dof != 1 ) {
+                     "  Details:\n"
+                     "        N       nnz       %s\n",
+                     ( spm->dof != 1 ) ? "Nexp    NNZexp     " : "" );
+        }
+        for( c=0; c<spm->clustnbr; c++ ) {
+            if ( spm->clustnum == c ) {
                 fprintf( stream,
-                         " %8ld %11ld\n",
-                         (long)spm->nexp, (long)spm->nnzexp );
+                         "    %2d: %7ld %9ld",
+                         spm->clustnum, (long)spm->n, (long)spm->nnz );
+
+                if ( spm->dof != 1 ) {
+                    fprintf( stream,
+                             " %8ld %11ld\n",
+                             (long)spm->nexp, (long)spm->nnzexp );
+                }
             }
+            MPI_Barrier( spm->comm );
         }
     }
     fflush( stream );