[petsc-dev] redefine (or remove) MatPreallocateSymmetricInitialize to MatPreallocateInitialize

[Barry Smith]

   Lisandro,

     What is the motivation? 

      MatPreallocateSymmetricInitialize() is only trivially different than MatPreallocateInitialize() so why clutter the code with both?

     If it doesn't need to exist then remove it completely, don't keep it at all.

   Barry

On Mar 31, 2012, at 7:45 AM, Lisandro Dalcin wrote:

> The patch at the end is perhaps a little hard to read, but the basic
> idea is to redefine (or eventually remove)
> MatPreallocateSymmetricInitialize, and use MatPreallocateInitialize.
> For this, all what is required is to somehow trick the C compiler to
> not complain about unused-but-set-variable (the -W warning name for
> GCC). That is the "__start = 0; __end = __start;" change in the first
> hunk.
> 
> If you agree, I'll like to push this change, and next I'll update the
> code to use MatPreallocateInitialize() in all cases... What I'm not
> sure is about removing MatPreallocateSymmetricInitialize, as it could
> potentially break user code.
> 
> 
> diff -r de0779566bd9 include/petscmat.h
> --- a/include/petscmat.h	Fri Mar 30 16:54:32 2012 -0500
> +++ b/include/petscmat.h	Sat Mar 31 15:27:23 2012 +0300
> @@ -735,7 +735,7 @@
>   PetscErrorCode _4_ierr; PetscInt __nrows = (nrows),__ctmp =
> (ncols),__rstart,__start,__end; \
>   _4_ierr = PetscMalloc2(__nrows,PetscInt,&dnz,__nrows,PetscInt,&onz);CHKERRQ(_4_ierr);
> \
>   _4_ierr = PetscMemzero(dnz,__nrows*sizeof(PetscInt));CHKERRQ(_4_ierr);\
> -  _4_ierr = PetscMemzero(onz,__nrows*sizeof(PetscInt));CHKERRQ(_4_ierr);\
> +  _4_ierr = PetscMemzero(onz,__nrows*sizeof(PetscInt));CHKERRQ(_4_ierr);
> __start = 0; __end = __start; \
>   _4_ierr = MPI_Scan(&__ctmp,&__end,1,MPIU_INT,MPI_SUM,comm);CHKERRQ(_4_ierr);
> __start = __end - __ctmp;\
>   _4_ierr = MPI_Scan(&__nrows,&__rstart,1,MPIU_INT,MPI_SUM,comm);CHKERRQ(_4_ierr);
> __rstart = __rstart - __nrows;
> 
> @@ -772,14 +772,7 @@
> .seealso: MatPreallocateFinalize(), MatPreallocateSet(),
> MatPreallocateSymmetricSet(), MatPreallocateSetLocal(),
>           MatPreallocateInitialize(), MatPreallocateSymmetricSetLocal()
> M*/
> -#define MatPreallocateSymmetricInitialize(comm,nrows,ncols,dnz,onz) 0; \
> -{ \
> -  PetscErrorCode _4_ierr; PetscInt __nrows = (nrows),__ctmp =
> (ncols),__rstart,__end; \
> -  _4_ierr = PetscMalloc2(__nrows,PetscInt,&dnz,__nrows,PetscInt,&onz);CHKERRQ(_4_ierr);
> \
> -  _4_ierr = PetscMemzero(dnz,__nrows*sizeof(PetscInt));CHKERRQ(_4_ierr);\
> -  _4_ierr = PetscMemzero(onz,__nrows*sizeof(PetscInt));CHKERRQ(_4_ierr);\
> -  _4_ierr = MPI_Scan(&__ctmp,&__end,1,MPIU_INT,MPI_SUM,comm);CHKERRQ(_4_ierr);\
> -  _4_ierr = MPI_Scan(&__nrows,&__rstart,1,MPIU_INT,MPI_SUM,comm);CHKERRQ(_4_ierr);
> __rstart = __rstart - __nrows;
> +#define MatPreallocateSymmetricInitialize(comm,nrows,ncols,dnz,onz)
> MatPreallocateInitialize(comm,nrows,ncols,dnz,onz)
> 
> /*MC
>    MatPreallocateSetLocal - Indicates the locations (rows and
> columns) in the matrix where nonzeros will be
> 
> 
> -- 
> Lisandro Dalcin
> ---------------
> CIMEC (INTEC/CONICET-UNL)
> Predio CONICET-Santa Fe
> Colectora RN 168 Km 472, Paraje El Pozo
> 3000 Santa Fe, Argentina
> Tel: +54-342-4511594 (ext 1011)
> Tel/Fax: +54-342-4511169