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

@@ -86,9 +86,12 @@ static int (*conversionTable[3][3][6])(spmatrix_t*) = {
  * @param[inout] spm
  *          The sparse matrix to init.
  *
+ * @param[in] comm
+ *          The MPI communicator used for the sparse matrix. MPI_COMM_WORLD by default.
+ *
  *******************************************************************************/
 void
-spmInit( spmatrix_t *spm )
+spmInitDist( spmatrix_t *spm, SPM_Comm comm )
 {
     spm->mtxtype = SpmGeneral;
     spm->flttype = SpmDouble;
@@ -114,7 +117,7 @@ spmInit( spmatrix_t *spm )
     spm->values   = NULL;
 
     spm->glob2loc = NULL;
-    spm->comm     = MPI_COMM_WORLD;
+    spm->comm     = comm;
 #if defined(SPM_WITH_MPI)
     MPI_Comm_rank( spm->comm, &(spm->clustnum) );
     MPI_Comm_size( spm->comm, &(spm->clustnbr) );
@@ -124,7 +127,6 @@ spmInit( spmatrix_t *spm )
 #endif /* defined(SPM_WITH_MPI) */
 }
 
-#if defined(SPM_WITH_MPI)
 /**
  *******************************************************************************
  *
@@ -137,37 +139,10 @@ spmInit( spmatrix_t *spm )
  *
  *******************************************************************************/
 void
-spmInitDist( spmatrix_t *spm, SPM_Comm comm )
+spmInit( spmatrix_t *spm )
 {
-    spm->mtxtype = SpmGeneral;
-    spm->flttype = SpmDouble;
-    spm->fmttype = SpmCSC;
-
-    spm->gN   = -1;
-    spm->n    = 0;
-    spm->gnnz = -1;
-    spm->nnz  = 0;
-
-    spm->gNexp   = -1;
-    spm->nexp    = -1;
-    spm->gnnzexp = -1;
-    spm->nnzexp  = -1;
-
-    spm->dof      = 1;
-    spm->dofs     = NULL;
-    spm->layout   = SpmColMajor;
-
-    spm->colptr   = NULL;
-    spm->rowptr   = NULL;
-    spm->loc2glob = NULL;
-    spm->values   = NULL;
-
-    spm->glob2loc = NULL;
-    spm->comm     = comm;
-    MPI_Comm_rank( comm, &(spm->clustnum) );
-    MPI_Comm_size( comm, &(spm->clustnbr) );
+    spmInitDist( spm, MPI_COMM_WORLD );
 }
-#endif /* defined(SPM_WITH_MPI) */
 
 /**
  *******************************************************************************