int
pzgstrf_column_dfs(
const int pnum, /* process number */
const int m, /* number of rows in the matrix */
const int jcol, /* current column in the panel */
const int fstcol, /* first column in the panel */
int *perm_r, /* row pivotings that are done so far */
int *ispruned, /* in */
int *col_lsub, /* the RHS vector to start the dfs */
int lsub_end, /* size of col_lsub[] */
int *super_bnd,/* supernode partition by upper bound */
int *nseg, /* modified - with new segments appended */
int *segrep, /* modified - with new segments appended */
int *repfnz, /* modified */
int *xprune, /* modified */
int *marker2, /* modified */
int *parent, /* working array */
int *xplore, /* working array */
pxgstrf_shared_t *pxgstrf_shared /* modified */
)
{
/*
* -- SuperLU MT routine (version 2.0) --
* Lawrence Berkeley National Lab, Univ. of California Berkeley,
* and Xerox Palo Alto Research Center.
* September 10, 2007
*
* Purpose
* =======
* pzgstrf_column_dfs() performs a symbolic factorization on column jcol,
* and detects whether column jcol belongs in the same supernode as jcol-1.
*
* Local parameters
* ================
* A supernode representative is the last column of a supernode.
* The nonzeros in U[*,j] are segments that end at supernodal
* representatives. The routine returns a list of such supernodal
* representatives in topological order of the dfs that generates them.
* The location of the first nonzero in each such supernodal segment
* (supernodal entry location) is also returned.
*
* nseg: no of segments in current U[*,j]
* samesuper: samesuper=NO if column j does not belong in the same
* supernode as j-1. Otherwise, samesuper=YES.
*
* marker2: A-row --> A-row/col (0/1)
* repfnz: SuperA-col --> PA-row
* parent: SuperA-col --> SuperA-col
* xplore: SuperA-col --> index to L-structure
*
* Return value
* ============
* 0 success;
* > 0 number of bytes allocated when run out of space.
*
*/
GlobalLU_t *Glu = pxgstrf_shared->Glu; /* modified */
Gstat_t *Gstat = pxgstrf_shared->Gstat; /* modified */
register int jcolm1, jcolm1size, nextl, ifrom;
register int k, krep, krow, kperm, samesuper, nsuper;
register int no_lsub;
int fsupc; /* first column in a supernode */
int myfnz; /* first nonz column in a U-segment */
int chperm, chmark, chrep, kchild;
int xdfs, maxdfs, kpar;
int ito; /* Used to compress row subscripts */
int mem_error;
int *xsup, *xsup_end, *supno, *lsub, *xlsub, *xlsub_end;
static int first = 1, maxsuper;
if ( first ) {
maxsuper = sp_ienv(3);
first = 0;
}
/* Initialize pointers */
xsup = Glu->xsup;
xsup_end = Glu->xsup_end;
supno = Glu->supno;
lsub = Glu->lsub;
xlsub = Glu->xlsub;
xlsub_end = Glu->xlsub_end;
jcolm1 = jcol - 1;
nextl = lsub_end;
no_lsub = 0;
samesuper = YES;
/* Test whether the row structure of column jcol is contained
in that of column jcol-1. */
for (k = 0; k < lsub_end; ++k) {
krow = col_lsub[k];
if ( perm_r[krow] == EMPTY ) { /* krow is in L */
++no_lsub;
if (marker2[krow] != jcolm1)
samesuper = NO; /* row subset test */
marker2[krow] = jcol;
}
}
#if ( DEBUGlevel>=2 )
if (jcol == BADCOL)
printf("(%d) pzgstrf_column_dfs[1] %d, fstcol %d, lsub_end %d, no_lsub %d, samesuper? %d\n",
pnum, jcol, fstcol, lsub_end, no_lsub, samesuper);
#endif
/*
* For each nonzero in A[fstcol:n,jcol] perform DFS ...
*/
for (k = 0; k < lsub_end; ++k) {
krow = col_lsub[k];
/* if krow was visited before, go to the next nonzero */
if ( marker2[krow] == jcol ) continue;
marker2[krow] = jcol;
kperm = perm_r[krow];
#if ( DEBUGlevel>=3 )
if (jcol == BADCOL)
printf("(%d) pzgstrf_column_dfs[inner]: perm_r[krow=%d] %d\n", pnum, krow, kperm);
#endif
/* Ignore the nonzeros in U corresponding to the busy columns
during the panel DFS. */
/*if ( lbusy[kperm] != fstcol ) { xiaoye? */
if ( kperm >= fstcol ) {
/*
* krow is in U: if its supernode representative krep
* has been explored, update repfnz[*].
*/
krep = SUPER_REP(supno[kperm]);
myfnz = repfnz[krep];
#if ( DEBUGlevel>=3 )
if (jcol == BADCOL)
printf("(%d) pzgstrf_column_dfs[inner-U]: krep %d, myfnz %d, kperm %d\n",
pnum, krep, myfnz, kperm);
#endif
if ( myfnz != EMPTY ) { /* Visited before */
if ( myfnz > kperm ) repfnz[krep] = kperm;
/* continue; */
} else {
/* Otherwise, perform dfs starting at krep */
parent[krep] = EMPTY;
repfnz[krep] = kperm;
if ( ispruned[krep] ) {
if ( SINGLETON( supno[krep] ) )
xdfs = xlsub_end[krep];
else xdfs = xlsub[krep];
maxdfs = xprune[krep];
#ifdef PROFILE
Gstat->procstat[pnum].pruned++;
#endif
} else {
fsupc = SUPER_FSUPC( supno[krep] );
xdfs = xlsub[fsupc] + krep-fsupc+1;
maxdfs = xlsub_end[fsupc];
#ifdef PROFILE
Gstat->procstat[pnum].unpruned++;
#endif
}
do {
/*
* For each unmarked kchild of krep ...
*/
while ( xdfs < maxdfs ) {
kchild = lsub[xdfs];
xdfs++;
chmark = marker2[kchild];
if ( chmark != jcol ) { /* Not reached yet */
marker2[kchild] = jcol;
chperm = perm_r[kchild];
if ( chperm == EMPTY ) {
/* kchild is in L: place it in L[*,k]. */
++no_lsub;
col_lsub[nextl++] = kchild;
if (chmark != jcolm1) samesuper = NO;
} else {
/* kchild is in U: chrep = its supernode
* representative. If its rep has
* been explored, update its repfnz[*].
*/
chrep = SUPER_REP( supno[chperm] );
myfnz = repfnz[chrep];
if ( myfnz != EMPTY ) { /* Visited before */
if ( myfnz > chperm )
repfnz[chrep] = chperm;
} else {
/* Continue dfs at super-rep of kchild */
xplore[krep] = xdfs;
xplore[m + krep] = maxdfs;
parent[chrep] = krep;
krep = chrep; /* Go deeper down G(L^t) */
repfnz[krep] = chperm;
if ( ispruned[krep] ) {
if ( SINGLETON( supno[krep] ) )
xdfs = xlsub_end[krep];
else xdfs = xlsub[krep];
maxdfs = xprune[krep];
#ifdef PROFILE
Gstat->procstat[pnum].pruned++;
#endif
} else {
fsupc = SUPER_FSUPC( supno[krep] );
xdfs = xlsub[fsupc] + krep-fsupc+1;
maxdfs = xlsub_end[fsupc];
#ifdef PROFILE
Gstat->procstat[pnum].unpruned++;
#endif
}
}
} /* else */
} /* if */
} /* while */
/* krow has no more unexplored nbrs:
* place supernode-rep krep in postorder DFS,
* backtrack dfs to its parent.
*/
segrep[*nseg] = krep;
++(*nseg);
#if ( DEBUGlevel>=3 )
if (jcol == BADCOL)
printf("(%d) pzgstrf_column_dfs[inner-dfs] new nseg %d, repfnz[krep=%d] %d\n",
pnum, *nseg, krep, repfnz[krep]);
#endif
kpar = parent[krep]; /* Pop from stack, mimic recursion */
if ( kpar == EMPTY ) break; /* dfs done */
krep = kpar;
xdfs = xplore[krep];
maxdfs = xplore[m + krep];
} while ( kpar != EMPTY ); /* Do ... until empty stack */
} /* else myfnz ... */
} /* if kperm >= fstcol ... */
} /* for each nonzero ... */
#if ( DEBUGlevel>=3 )
if (jcol == BADCOL)
printf("(%d) pzgstrf_column_dfs[2]: nextl %d, samesuper? %d\n",
pnum, nextl, samesuper);
#endif
/* assert(no_lsub == nextl - no_usub);*/
/* ---------------------------------------------------------
Check to see if j belongs in the same supernode as j-1.
--------------------------------------------------------- */
/* Does it matter if jcol == 0? - xiaoye */
if ( samesuper == YES ) {
nsuper = supno[jcolm1];
jcolm1size = xlsub_end[jcolm1] - xlsub[jcolm1];
#if ( DEBUGlevel>=3 )
if (jcol == BADCOL)
printf("(%d) pzgstrf_column_dfs[YES] jcol-1 %d, jcolm1size %d, supno[%d] %d\n",
pnum, jcolm1, jcolm1size, jcolm1, nsuper);
#endif
if ( no_lsub != jcolm1size-1 )
samesuper = NO; /* Enforce T2 supernode */
else {
/* Make sure the number of columns in a supernode does not
exceed threshold. */
fsupc = xsup[nsuper];
if ( jcol - fsupc >= maxsuper )
samesuper = NO;
else {
/* start of a supernode in H (coarser partition) */
if ( super_bnd[jcol] != 0 ) samesuper = NO;
}
}
}
/* If jcol starts a new supernode, allocate storage for
* the subscript set of both first and last column of
* a previous supernode. (first for num values, last for pruning)
*/
if ( samesuper == NO ) { /* starts a new supernode */
nsuper = NewNsuper(pnum, pxgstrf_shared, &Glu->nsuper);
xsup[nsuper] = jcol;
/* Copy column jcol; also reserve space to store pruned graph */
if ((mem_error = Glu_alloc(pnum, jcol, 2*no_lsub, LSUB, &ito,
pxgstrf_shared)))
return mem_error;
xlsub[jcol] = ito;
lsub = Glu->lsub;
for (ifrom = 0; ifrom < nextl; ++ifrom) {
krow = col_lsub[ifrom];
if ( perm_r[krow] == EMPTY ) /* Filter U-subscript */
lsub[ito++] = krow;
}
k = ito;
xlsub_end[jcol] = k;
/* Make a copy in case it is a singleton supernode */
for (ifrom = xlsub[jcol]; ifrom < ito; ++ifrom)
lsub[k++] = lsub[ifrom];
} else { /* Supernode of size > 1: overwrite column jcol-1 */
k = xlsub_end[fsupc];
xlsub[jcol] = k;
xprune[fsupc] = k;
for (ifrom = 0; ifrom < nextl; ++ifrom) {
krow = col_lsub[ifrom];
if ( perm_r[krow] == EMPTY ) /* Filter U-subscript */
lsub[k++] = krow;
}
xlsub_end[jcol] = k;
}
#if ( DEBUGlevel>=3 )
if (jcol == BADCOL) {
printf("(%d) pzgstrf_column_dfs[3]: %d in prev s-node %d? %d\n",
pnum, jcol, fsupc, samesuper);
PrintInt10("lsub", xlsub_end[jcol]-xlsub[jcol], &lsub[xlsub[jcol]]);
}
#endif
/* Tidy up the pointers before exit */
xprune[jcol] = k; /* upper bound for pruning */
supno[jcol] = nsuper;
xsup_end[nsuper] = jcol + 1;
return 0;
}
int
psgstrf_snode_dfs(
const int pnum, /* process number */
const int jcol, /* in - start of the supernode */
const int kcol, /* in - end of the supernode */
const int *asub, /* in */
const int *xa_begin, /* in */
const int *xa_end, /* in */
int *xprune, /* out */
int *marker, /* modified */
int *col_lsub, /* values are irrelevant on entry
and on return */
pxgstrf_shared_t *pxgstrf_shared /* modified */
)
{
/*
* -- SuperLU MT routine (version 2.0) --
* Lawrence Berkeley National Lab, Univ. of California Berkeley,
* and Xerox Palo Alto Research Center.
* September 10, 2007
*
* Purpose
* =======
* psgstrf_snode_dfs() determines the union of the row structures of
* those columns within the relaxed snode.
* Note: The relaxed snodes are leaves of the supernodal etree,
* therefore, the portion outside the rectangular supernode must be zero.
*
* Return value
* ============
* 0 success;
* >0 number of bytes allocated when run out of memory.
*
*/
GlobalLU_t *Glu = pxgstrf_shared->Glu;
register int i, k, ifrom, nextl, nsuper;
int ito;
int krow, kmark, mem_error;
int *supno, *lsub, *xlsub, *xlsub_end;
supno = Glu->supno;
xlsub = Glu->xlsub;
xlsub_end = Glu->xlsub_end;
nsuper = NewNsuper(pnum, pxgstrf_shared, &Glu->nsuper);
Glu->xsup[nsuper] = jcol;
Glu->xsup_end[nsuper] = kcol + 1;
nextl = 0;
for (i = jcol; i <= kcol; i++) {
/* for each nonzero in A[*,i] */
for (k = xa_begin[i]; k < xa_end[i]; k++) {
krow = asub[k];
kmark = marker[krow];
if ( kmark != kcol ) { /* First time visit krow */
marker[krow] = kcol;
col_lsub[nextl++] = krow;
}
}
supno[i] = nsuper;
}
if ( (mem_error = Glu_alloc(pnum, jcol, 2*nextl, LSUB, &ito,
pxgstrf_shared)) )
return mem_error;
xlsub[jcol] = ito;
lsub = Glu->lsub;
for (ifrom = 0; ifrom < nextl; ++ifrom)
lsub[ito++] = col_lsub[ifrom];
xlsub_end[jcol] = ito;
return 0;
}