dsdu_qhb.c_plaq

/****** dsdu_qhb.c  -- compute the staple ******************/
/* MIMD version 5 */

#include "symanzik_sl32_includes.h"

void dsdu_qhb(int dir1, int subl) 
{
register int i,dir2;
register site *st;
msg_tag *tag0,*tag1,*tag2,*tag3;
int start, downsubl;
su3_matrix tmat1,tmat2;

	/* Loop over other directions, computing force from plaquettes in
	   the dir1,dir2 plane */
	start=1; /* indicates staple sum not initialized */
	for(dir2=XUP;dir2<=TUP;dir2++)if(dir2 != dir1)
	{
	    /* sublattice in the downward direction */
	    downsubl = neighsubl[subl][OPP_DIR(dir2)];
	    /* get link[dir2] from direction dir1 */
	    tag0 = start_gather( F_OFFSET(link[dir2]), sizeof(su3_matrix),
		dir1, downsubl, gen_pt[0] );

	    /* get link[dir1] from direction dir2 */
	    tag1 = start_gather( F_OFFSET(link[dir1]), sizeof(su3_matrix),
		dir2, subl, gen_pt[1] );

	    /* get link[dir2] from direction dir1 */
	    tag2 = start_gather( F_OFFSET(link[dir2]), sizeof(su3_matrix),
		dir1, subl, gen_pt[2] );

	    /* Start lower staple at downward site */
	    FORSOMESUBLATTICE(i,st,downsubl){
		mult_su3_an( &(st->link[dir2]), &(st->link[dir1]),
		    &(st->tempmat1) );
	    }

	    /* Finish lower staple at downward site */
	    wait_gather(tag0);
	    FORSOMESUBLATTICE(i,st,downsubl){
		mult_su3_nn( &(st->tempmat1), (su3_matrix *)gen_pt[0][i],
		    &(st->tempmat2) );
	    }
	    cleanup_gather(tag0);

	    /* Now gather up */
	    tag3 = start_gather( F_OFFSET(tempmat2), sizeof(su3_matrix),
		OPP_DIR(dir2), subl, gen_pt[3] );

	    /* Upper staple */
	    wait_gather(tag1);
	    wait_gather(tag2);
	    if(start){  /* this is the first contribution to staple */
		FORSOMESUBLATTICE(i,st,subl){
		    mult_su3_nn( &(st->link[dir2]), (su3_matrix *)gen_pt[1][i],
			&tmat1 );
		    mult_su3_na( &tmat1, (su3_matrix *)gen_pt[2][i],
			&(st->staple));
		}
		start=0; 
	    }
	    else{
		FORSOMESUBLATTICE(i,st,subl){
		    mult_su3_nn( &(st->link[dir2]), (su3_matrix *)gen_pt[1][i],
			&tmat1 );
		    mult_su3_na( &tmat1, (su3_matrix *)gen_pt[2][i], &tmat2 );
		    add_su3_matrix( &(st->staple), &tmat2, &(st->staple));
		}
	    } /* upper staple */
	    cleanup_gather(tag1);
	    cleanup_gather(tag2);

	    /* Now add lower staple */
	    wait_gather(tag3);
	    FORSOMESUBLATTICE(i,st,subl){
		add_su3_matrix( &(st->staple), (su3_matrix *)gen_pt[3][i],
		    &(st->staple));
	    } /* lower staple */
	    cleanup_gather(tag3);
	}
}