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|
/*****************************************************************************
/
/ SPACE (SPArse Cholesky Elimination) Library: interface.c
/
/ author J"urgen Schulze, University of Paderborn
/ created 01jan26
/
/ This file contains some high level interface functions (only these
/ functions should be called by a user).
/
******************************************************************************/
#include <space.h>
/*****************************************************************************
o Input:
undirected graph G
options -- if NULL, default options are used
option[0] holds OPTION_ORDTYPE
option[1] holds OPTION_NODE_SELECTION1
option[2] holds OPTION_NODE_SELECTION2
option[3] holds OPTION_NODE_SELECTION3
option[4] holds OPTION_DOMAIN_SIZE
option[5] holds OPTION_MSGLVL
o Output:
elimination/front tree T reflecting the ordering of G
cpus -- if NULL, no timing information is pulled back
cpus[0] holds TIME_COMPRESS
cpus[1] holds TIME_MS
cpus[2] holds TIME_MULTILEVEL
cpus[3] holds TIME_INITDOMDEC
cpus[4] holds TIME_COARSEDOMDEC
cpus[5] holds TIME_INITSEP
cpus[6] holds TIME_REFINESEP
cpus[7] holds TIME_SMOOTH
cpus[8] holds TIME_BOTTOMUP
cpus[9] holds TIME_UPDADJNCY
cpus[10] holds TIME_FINDINODES
cpus[11] holds TIME_UPDSCORE
o Comments:
this function computes an ordering for G; it returns an elimination
tree T; permutation vectors perm, invp can be extracted from T by
calling function permFromElimTree(T, perm, invp)
******************************************************************************/
elimtree_t*
SPACE_ordering(graph_t *G, options_t *options, timings_t *cpus)
{ graph_t *Gc;
multisector_t *ms;
minprior_t *minprior;
elimtree_t *T, *T2;
timings_t cpusOrd[ORD_TIME_SLOTS];
options_t default_options[] = { SPACE_ORDTYPE, SPACE_NODE_SELECTION1,
SPACE_NODE_SELECTION2, SPACE_NODE_SELECTION3,
SPACE_DOMAIN_SIZE, SPACE_MSGLVL };
PORD_INT *vtxmap, istage, totnstep, totnzf;
FLOAT totops;
/* --------------------------------------------------
set default options, if no other options specified
-------------------------------------------------- */
if (options == NULL)
options = default_options;
/* ----------------
reset all timers
---------------- */
pord_resettimer(cpusOrd[TIME_COMPRESS]);
pord_resettimer(cpusOrd[TIME_MS]);
pord_resettimer(cpusOrd[TIME_MULTILEVEL]);
pord_resettimer(cpusOrd[TIME_INITDOMDEC]);
pord_resettimer(cpusOrd[TIME_COARSEDOMDEC]);
pord_resettimer(cpusOrd[TIME_INITSEP]);
pord_resettimer(cpusOrd[TIME_REFINESEP]);
pord_resettimer(cpusOrd[TIME_SMOOTH]);
pord_resettimer(cpusOrd[TIME_BOTTOMUP]);
pord_resettimer(cpusOrd[TIME_UPDADJNCY]);
pord_resettimer(cpusOrd[TIME_FINDINODES]);
pord_resettimer(cpusOrd[TIME_UPDSCORE]);
/* ------------------
compress the graph
------------------ */
pord_starttimer(cpusOrd[TIME_COMPRESS]);
mymalloc(vtxmap, G->nvtx, PORD_INT);
Gc = compressGraph(G, vtxmap);
pord_stoptimer(cpusOrd[TIME_COMPRESS]);
if (Gc != NULL)
{ if (options[OPTION_MSGLVL] > 0)
printf("compressed graph constructed (#nodes %d, #edges %d)\n",
Gc->nvtx, Gc->nedges >> 1);
}
else
{ Gc = G;
free(vtxmap);
if (options[OPTION_MSGLVL] > 0)
printf("no compressed graph constructed\n");
}
/* -------------------
compute multisector
------------------- */
pord_starttimer(cpusOrd[TIME_MS]);
ms = constructMultisector(Gc, options, cpusOrd);
pord_stoptimer(cpusOrd[TIME_MS]);
if (options[OPTION_MSGLVL] > 0)
printf("quality of multisector: #stages %d, #nodes %d, weight %d\n",
ms->nstages, ms->nnodes, ms->totmswght);
/* ---------------------------------
compute minimum priority ordering
--------------------------------- */
pord_starttimer(cpusOrd[TIME_BOTTOMUP])
minprior = setupMinPriority(ms);
T = orderMinPriority(minprior, options, cpusOrd);
pord_stoptimer(cpusOrd[TIME_BOTTOMUP]);
if (options[OPTION_MSGLVL] > 0)
{ totnstep = totnzf = 0;
totops = 0.0;
for (istage = 0; istage < ms->nstages; istage++)
{ totnstep += minprior->stageinfo[istage].nstep;
totnzf += minprior->stageinfo[istage].nzf;
totops += minprior->stageinfo[istage].ops;
}
printf("quality of ordering: #steps %d, nzl %d, ops %e\n", totnstep,
totnzf, totops);
}
/* -----------------------
expand elimination tree
----------------------- */
if (Gc != G)
{ T2 = expandElimTree(T, vtxmap, G->nvtx);
freeElimTree(T);
freeGraph(Gc);
free(vtxmap);
}
else T2 = T;
/* --------------------------------------------------
pull back timing results, if vector cpus available
-------------------------------------------------- */
if (cpus != NULL)
{ cpus[0] = cpusOrd[TIME_COMPRESS];
cpus[1] = cpusOrd[TIME_MS];
cpus[2] = cpusOrd[TIME_MULTILEVEL];
cpus[3] = cpusOrd[TIME_INITDOMDEC];
cpus[4] = cpusOrd[TIME_COARSEDOMDEC];
cpus[5] = cpusOrd[TIME_INITSEP];
cpus[6] = cpusOrd[TIME_REFINESEP];
cpus[7] = cpusOrd[TIME_SMOOTH];
cpus[8] = cpusOrd[TIME_BOTTOMUP];
cpus[9] = cpusOrd[TIME_UPDADJNCY];
cpus[10] = cpusOrd[TIME_FINDINODES];
cpus[11] = cpusOrd[TIME_UPDSCORE];
}
/* ----------------------
free memory and return
---------------------- */
freeMultisector(ms);
freeMinPriority(minprior);
return(T2);
}
#if defined(cleaned_version)
/*****************************************************************************
o Input:
elimination/front tree T
max. number of zeros that is allowed to be introduced in front
o Output:
transformed elimination/front tree T'
o Comments:
the goal is to make T (obtained by orderMinPriority or
setupElimTree) more appropiate for the multifrontal algorithm
******************************************************************************/
elimtree_t*
SPACE_transformElimTree(elimtree_t *T, PORD_INT maxzeros)
{ elimtree_t *T2, *T3;
/* -----------------------------------------------------
1st: determine the fundamental fronts
this step significantly improves the cache reuse
----------------------------------------------------- */
T2 = fundamentalFronts(T);
/* -----------------------------------------------------------------
2nd: group together small subtrees into one front
this step reduces the number of fronts and thus the overhead
associated with them; the expense is added storage for the
logically zero entries and the factor operations on them
------------------------------------------------------------------ */
T3 = mergeFronts(T2, maxzeros);
freeElimTree(T2);
/* --------------------------------------------------------------
3rd: order the children of a front so that the working storage
in the multifrontal algorithm is minimized
-------------------------------------------------------------- */
(void)justifyFronts(T3);
return(T3);
}
/*****************************************************************************
o Input:
transformed elimination/front tree T, input matrix A
o Output:
initial factor matrix L of the permuted input matrix PAP
o Comments: L contains nonzeros of PAP; all other entries are set to 0.0
******************************************************************************/
factorMtx_t*
SPACE_symbFac(elimtree_t *T, inputMtx_t *A)
{ factorMtx_t *L;
frontsub_t *frontsub;
css_t *css;
inputMtx_t *PAP;
elimtree_t *PTP;
PORD_INT *perm, neqs, nelem;
/* ------------------------------------------------------
extract permutation vectors from T and permute T and A
------------------------------------------------------ */
neqs = A->neqs;
mymalloc(perm, neqs, PORD_INT);
permFromElimTree(T, perm);
PTP = permuteElimTree(T, perm);
PAP = permuteInputMtx(A, perm);
/* -------------------------------------------------------------------
create factor matrix L of PAP, i.e.
(1) create the subscript structure of the fronts, i.e. frontsub
(2) use frontsub to create the compressed subscript structure of L
(3) allocate memory for L and the nonzeros of L, i.e. L->nzl
(4) init. L with the nonzeros of PAP
------------------------------------------------------------------- */
frontsub = setupFrontSubscripts(PTP, PAP);
css = setupCSSFromFrontSubscripts(frontsub);
nelem = css->xnzl[neqs];
L = newFactorMtx(nelem);
L->perm = perm;
L->frontsub = frontsub;
L->css = css;
initFactorMtx(L, PAP);
/* -----------------------------------------------------
free permuted input matrix and return
note: PTP and perm have been inherited by frontsub, L
----------------------------------------------------- */
freeInputMtx(PAP);
return(L);
}
/*****************************************************************************
o Input:
transformed elimination/front tree
initial factor matrix L of the permuted input matrix PAP
o Output:
factor matrix L of the permuted input matrix PAP
cpus -- if NULL no timing information is pulled back
cpus[0] holds TIME_INITFRONT
cpus[1] holds TIME_EXPAND
cpus[2] holds TIME_KERNEL
cpus[3] holds TIME_INITUPD
o Comments:
this function does the actual numerical factorization; to
improve register and cache reuse it uses a kernel of size 3x3
******************************************************************************/
void
SPACE_numFac(factorMtx_t *L, timings_t *cpus)
{ timings_t cpusFactor[NUMFAC_TIME_SLOTS];
/* ----------------
reset all timers
---------------- */
pord_resettimer(cpusFactor[TIME_INITFRONT]);
pord_resettimer(cpusFactor[TIME_EXADD]);
pord_resettimer(cpusFactor[TIME_KERNEL]);
pord_resettimer(cpusFactor[TIME_INITUPD]);
/* -------------------------
compute Cholesky factor L
------------------------- */
numfac(L, cpusFactor);
/* --------------------------------------------------
pull back timing results, if vector cpus available
-------------------------------------------------- */
if (cpus != NULL)
{ cpus[0] = cpusFactor[TIME_INITFRONT];
cpus[1] = cpusFactor[TIME_EXADD];
cpus[2] = cpusFactor[TIME_KERNEL];
cpus[3] = cpusFactor[TIME_INITUPD];
}
}
/*****************************************************************************
o Input:
transformed elimination/front tree
factor matrix L of the permuted input matrix PAP
right hand side vector rhs of the original system Ax = b
o Output:
solution vector xvec of the original system Ax = b
o Comments:
this function solves the remaining triangular systems;
******************************************************************************/
void
SPACE_solveTriangular(factorMtx_t *L, FLOAT *rhs, FLOAT *xvec)
{ FLOAT *yvec;
PORD_INT *perm;
PORD_INT neqs, k;
perm = L->perm;
neqs = L->css->neqs;
/* -------------------------------------------
set up permuted right hand side vector yvec
------------------------------------------- */
mymalloc(yvec, neqs, FLOAT);
for (k = 0; k < neqs; k++)
yvec[perm[k]] = rhs[k];
/* -------------------------
solve Ly = b and L^Tz = y
------------------------- */
forwardSubst1x1(L, yvec);
backwardSubst1x1(L, yvec);
/* ---------------------------------------------------------------
extract from yvec the solution vector of the un-permuted system
--------------------------------------------------------------- */
for (k = 0; k < neqs; k++)
xvec[k] = yvec[perm[k]];
free(yvec);
}
/*****************************************************************************
o Input:
sparse matrix A, right hand side vector rhs
options -- if NULL, default options are used
option[0] holds OPTION_ORDTYPE
option[1] holds OPTION_NODE_SELECTION1
option[2] holds OPTION_NODE_SELECTION2
option[3] holds OPTION_NODE_SELECTION3
option[4] holds OPTION_DOMAIN_SIZE
option[5] holds OPTION_MSGLVL
option[6] holds OPTION_ETREE_NONZ
o Output:
solution vector xvec of the original system Ax = b
cpus -- if NULL, no timing information is pulled back
cpus[0] holds time to construct the graph
cpus[1] holds time to compute the ordering
cpus[2] holds TIME_COMPRESS
cpus[3] holds TIME_MS
cpus[4] holds TIME_MULTILEVEL
cpus[5] holds TIME_INITDOMDEC
cpus[6] holds TIME_COARSEDOMDEC
cpus[7] holds TIME_INITSEP
cpus[8] holds TIME_REFINESEP
cpus[9] holds TIME_SMOOTH
cpus[10] holds TIME_BOTTOMUP
cpus[11] holds TIME_UPDADJNCY;
cpus[12] holds TIME_FINDINODES
cpus[13] holds TIME_UPDSCORE
cpus[14] holds time to transform the elimination tree
cpus[15] holds time to compute the symbolical factorization
cpus[16] holds time to compute the numerical factorization
cpus[17] holds TIME_INITFRONT
cpus[18] holds TIME_EXADD
cpus[19] holds TIME_KERNEL
cpus[20] holds TIME_INITUPD
cpus[21] holds time to solve the triangular systems
o Comments:
this is the final topmost function that can be used as a black
box in other algorithm; it provides a general purpose direct
solver for large sparse positive definite systems
******************************************************************************/
void
SPACE_solve(inputMtx_t *A, FLOAT *rhs, FLOAT *xvec, options_t *options,
timings_t *cpus)
{ graph_t *G;
elimtree_t *T, *T2;
factorMtx_t *L;
timings_t cpusOrd[ORD_TIME_SLOTS], cpusFactor[NUMFAC_TIME_SLOTS];
timings_t t_graph, t_ord, t_etree, t_symb, t_num, t_solvetri;
options_t default_options[] = { SPACE_ORDTYPE, SPACE_NODE_SELECTION1,
SPACE_NODE_SELECTION2, SPACE_NODE_SELECTION3,
SPACE_DOMAIN_SIZE, SPACE_MSGLVL, SPACE_ETREE_NONZ };
/* --------------------------------------------------
set default options, if no other options specified
-------------------------------------------------- */
if (options == NULL)
options = default_options;
/* ----------------
reset all timers
---------------- */
pord_resettimer(t_graph);
pord_resettimer(t_ord);
pord_resettimer(t_etree);
pord_resettimer(t_symb);
pord_resettimer(t_num);
pord_resettimer(t_solvetri);
/* -----------------
set up graph G(A)
----------------- */
pord_starttimer(t_graph);
G = setupGraphFromMtx(A);
pord_stoptimer(t_graph);
if (options[OPTION_MSGLVL] > 0)
printf("\ninduced graph constructed: #vertices %d, #edges %d, #components "
"%d\n", G->nvtx, G->nedges >> 1, connectedComponents(G));
/* --------------------------------------------
construct ordering/elimination tree for G(A)
-------------------------------------------- */
pord_starttimer(t_ord);
T = SPACE_ordering(G, options, cpusOrd);
pord_stoptimer(t_ord);
freeGraph(G);
if (options[OPTION_MSGLVL] > 0)
printf("quality of initial elim. tree: #fronts %d, #indices %d\n\t"
"nzl %d, ops %e, wspace %d\n", T->nfronts, nFactorIndices(T),
nFactorEntries(T), nFactorOps(T), nWorkspace(T));
/* -------------------------------
elimination tree transformation
------------------------------- */
pord_starttimer(t_etree);
T2 = SPACE_transformElimTree(T, options[OPTION_ETREE_NONZ]);
pord_stoptimer(t_etree);
freeElimTree(T);
if (options[OPTION_MSGLVL] > 0)
printf("quality of transformed elim. tree: #fronts %d, #indices %d\n\t"
"nzl %d, ops %e, wspace %d\n", T2->nfronts, nFactorIndices(T2),
nFactorEntries(T2), nFactorOps(T2), nWorkspace(T2));
/* ------------------------
symbolical factorization
------------------------ */
pord_starttimer(t_symb);
L = SPACE_symbFac(T2, A);
pord_stoptimer(t_symb);
if (options[OPTION_MSGLVL] > 0)
printf("quality of factor matrix:\n\tneqs %d, #indices %d, nzl %d\n",
L->css->neqs, L->css->nind, L->nelem);
/* -----------------------
numerical factorization
----------------------- */
pord_starttimer(t_num);
SPACE_numFac(L, cpusFactor);
pord_stoptimer(t_num);
if (options[OPTION_MSGLVL] > 0)
printf("performance of numerical factorization: %6.2f mflops\n",
(double)nFactorOps(T2) / t_num / 1000000);
/* ------------------------------
solution of triangular systems
------------------------------ */
pord_starttimer(t_solvetri);
SPACE_solveTriangular(L, rhs, xvec);
pord_stoptimer(t_solvetri);
if (options[OPTION_MSGLVL] > 0)
printf("performance of forward/backward solve: %6.2f mflops\n",
(double)nTriangularOps(T2) / t_solvetri / 1000000);
freeElimTree(T2);
freeFactorMtx(L);
/* --------------------------------------------------
pull back timing results, if vector cpus available
-------------------------------------------------- */
if (cpus != NULL)
{ cpus[0] = t_graph;
cpus[1] = t_ord;
cpus[2] = cpusOrd[TIME_COMPRESS];
cpus[3] = cpusOrd[TIME_MS];
cpus[4] = cpusOrd[TIME_MULTILEVEL];
cpus[5] = cpusOrd[TIME_INITDOMDEC];
cpus[6] = cpusOrd[TIME_COARSEDOMDEC];
cpus[7] = cpusOrd[TIME_INITSEP];
cpus[8] = cpusOrd[TIME_REFINESEP];
cpus[9] = cpusOrd[TIME_SMOOTH];
cpus[10] = cpusOrd[TIME_BOTTOMUP];
cpus[11] = cpusOrd[TIME_UPDADJNCY];
cpus[12] = cpusOrd[TIME_FINDINODES];
cpus[13] = cpusOrd[TIME_UPDSCORE];
cpus[14] = t_etree;
cpus[15] = t_symb;
cpus[16] = t_num;
cpus[17] = cpusFactor[TIME_INITFRONT];
cpus[18] = cpusFactor[TIME_EXADD];
cpus[19] = cpusFactor[TIME_KERNEL];
cpus[20] = cpusFactor[TIME_INITUPD];
cpus[21] = t_solvetri;
}
}
/*****************************************************************************
o Input:
sparse matrix A with permutation vector perm
right hand side vector rhs
options -- if NULL, default options are used
option[0] holds OPTION_MSGLVL
option[1] holds OPTION_ETREE_NONZ
o Output:
solution vector xvec of the original system Ax = b
cpus -- if NULL, no timing information is pulled back
cpus[0] holds time to construct the graph
cpus[1] holds time to construct the elimination tree
cpus[2] holds time to transform the elimination tree
cpus[3] holds time to compute the symbolical factorization
cpus[4] holds time to compute the numerical factorization
cpus[5] holds TIME_INITFRONT
cpus[6] holds TIME_EXADD
cpus[7] holds TIME_KERNEL
cpus[8] holds TIME_INITUPD
cpus[9] holds time to solve the triangular systems
o Comments:
this function can be used to solve an equation system
using an externally computed permutation vector
******************************************************************************/
void
SPACE_solveWithPerm(inputMtx_t *A, PORD_INT *perm, FLOAT *rhs, FLOAT *xvec,
options_t *options, timings_t *cpus)
{ graph_t *G;
elimtree_t *T, *T2;
factorMtx_t *L;
timings_t cpusFactor[NUMFAC_TIME_SLOTS], t_graph, t_etree_construct;
timings_t t_etree_merge, t_symb, t_num, t_solvetri;
options_t default_options[] = { SPACE_MSGLVL, SPACE_ETREE_NONZ };
PORD_INT *invp, i, msglvl, maxzeros;
/* --------------------------------------------------
set default options, if no other options specified
-------------------------------------------------- */
if (options == NULL)
options = default_options;
msglvl = options[0];
maxzeros = options[1];
/* ----------------
reset all timers
---------------- */
pord_resettimer(t_graph);
pord_resettimer(t_etree_construct);
pord_resettimer(t_etree_merge);
pord_resettimer(t_symb);
pord_resettimer(t_num);
pord_resettimer(t_solvetri);
/* -----------------
set up graph G(A)
----------------- */
pord_starttimer(t_graph);
G = setupGraphFromMtx(A);
pord_stoptimer(t_graph);
if (msglvl > 0)
printf("\ninduced graph constructed: #vertices %d, #edges %d, #components "
"%d\n", G->nvtx, G->nedges >> 1, connectedComponents(G));
/* ---------------------------------------------------
construct inital elimination tree according to perm
--------------------------------------------------- */
pord_starttimer(t_etree_construct);
mymalloc(invp, G->nvtx, PORD_INT);
for (i = 0; i < G->nvtx; i++)
invp[perm[i]] = i;
T = setupElimTree(G, perm, invp);
pord_stoptimer(t_etree_construct);
freeGraph(G);
free(invp);
if (msglvl > 0)
printf("quality of initial elim. tree: #fronts %d, #indices %d\n\t"
"nzl %d, ops %e, wspace %d\n", T->nfronts, nFactorIndices(T),
nFactorEntries(T), nFactorOps(T), nWorkspace(T));
/* -------------------------------
elimination tree transformation
------------------------------- */
pord_starttimer(t_etree_merge);
T2 = SPACE_transformElimTree(T, maxzeros);
pord_stoptimer(t_etree_merge);
freeElimTree(T);
if (msglvl > 0)
printf("quality of transformed elim. tree: #fronts %d, #indices %d\n\t"
"nzl %d, ops %e, wspace %d\n", T2->nfronts, nFactorIndices(T2),
nFactorEntries(T2), nFactorOps(T2), nWorkspace(T2));
/* ------------------------
symbolical factorization
------------------------ */
pord_starttimer(t_symb);
L = SPACE_symbFac(T2, A);
pord_stoptimer(t_symb);
if (msglvl > 0)
printf("quality of factor matrix:\n\tneqs %d, #indices %d, nzl %d\n",
L->css->neqs, L->css->nind, L->nelem);
/* -----------------------
numerical factorization
----------------------- */
pord_starttimer(t_num);
SPACE_numFac(L, cpusFactor);
pord_stoptimer(t_num);
if (msglvl > 0)
printf("performance of numerical factorization: %6.2f mflops\n",
(double)nFactorOps(T2) / t_num / 1000000);
/* ------------------------------
solution of triangular systems
------------------------------ */
pord_starttimer(t_solvetri);
SPACE_solveTriangular(L, rhs, xvec);
pord_stoptimer(t_solvetri);
if (msglvl > 0)
printf("performance of forward/backward solve: %6.2f mflops\n",
(double)nTriangularOps(T2) / t_solvetri / 1000000);
freeElimTree(T2);
freeFactorMtx(L);
/* --------------------------------------------------
pull back timing results, if vector cpus available
-------------------------------------------------- */
if (cpus != NULL)
{ cpus[0] = t_graph;
cpus[1] = t_etree_construct;
cpus[2] = t_etree_merge;
cpus[3] = t_symb;
cpus[4] = t_num;
cpus[5] = cpusFactor[TIME_INITFRONT];
cpus[6] = cpusFactor[TIME_EXADD];
cpus[7] = cpusFactor[TIME_KERNEL];
cpus[8] = cpusFactor[TIME_INITUPD];
cpus[9] = t_solvetri;
}
}
/*****************************************************************************
o Input:
graph G with permutation vector perm
options -- if NULL, default options are used
option[0] holds OPTION_MSGLVL
option[1] holds OPTION_ETREE_NONZ
option[2] holds OPTION_ETREE_BAL
option[3] holds dimension of hypercube
o Output:
mapping object map
cpus -- if NULL, no timing information is pulled back
cpus[0] holds time to construct the elimination tree
cpus[1] holds time to transform the elimination tree
cpus[2] holds time to compute the mapping
o Comments:
this function can be used to obtain a mapping object for the
parallel factorization
******************************************************************************/
mapping_t*
SPACE_mapping(graph_t *G, PORD_INT *perm, options_t *options, timings_t *cpus)
{ mapping_t *map;
elimtree_t *T, *T2;
timings_t t_etree_construct, t_etree_merge, t_map;
options_t default_options[] = { SPACE_MSGLVL, SPACE_ETREE_NONZ,
SPACE_ETREE_BAL, 2 };
PORD_INT *invp, i, msglvl, maxzeros, bal, dimQ;
/* --------------------------------------------------
set default options, if no other options specified
-------------------------------------------------- */
if (options == NULL)
options = default_options;
msglvl = options[0];
maxzeros = options[1];
bal = options[2];
dimQ = options[3];
/* ----------------
reset all timers
---------------- */
pord_resettimer(t_etree_construct);
pord_resettimer(t_etree_merge);
pord_resettimer(t_map);
/* ---------------------------------------------------
construct inital elimination tree according to perm
--------------------------------------------------- */
pord_starttimer(t_etree_construct);
mymalloc(invp, G->nvtx, PORD_INT);
for (i = 0; i < G->nvtx; i++)
invp[perm[i]] = i;
T = setupElimTree(G, perm, invp);
pord_stoptimer(t_etree_construct);
free(invp);
if (msglvl > 0)
printf("quality of initial elim. tree: #fronts %d, #indices %d\n\t"
"nzl %d, ops %e, wspace %d\n", T->nfronts, nFactorIndices(T),
nFactorEntries(T), nFactorOps(T), nWorkspace(T));
/* -------------------------------
elimination tree transformation
------------------------------- */
pord_starttimer(t_etree_merge);
T2 = SPACE_transformElimTree(T, maxzeros);
pord_stoptimer(t_etree_merge);
freeElimTree(T);
if (msglvl > 0)
printf("quality of transformed elim. tree: #fronts %d, #indices %d\n\t"
"nzl %d, ops %e, wspace %d\n", T2->nfronts, nFactorIndices(T2),
nFactorEntries(T2), nFactorOps(T2), nWorkspace(T2));
/* -------------------
compute the mapping
------------------- */
pord_starttimer(t_map);
map = setupMapping(T2, dimQ, bal);
pord_stoptimer(t_map);
/* --------------------------------------------------
pull back timing results, if vector cpus available
-------------------------------------------------- */
if (cpus != NULL)
{ cpus[0] = t_etree_construct;
cpus[1] = t_etree_merge;
cpus[2] = t_map;
}
/* --------------------------------------------------------------
return mapping object (don't free T2, since it belongs to map)
-------------------------------------------------------------- */
return(map);
}
#endif
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