static VariantSF bottom_leader(th_context *th, VariantSF to_sgf)
{
CPtr csf = subg_compl_stack_ptr(to_sgf) ;
while( prev_compl_frame(csf) < COMPLSTACKBOTTOM && !is_leader(csf) )
csf = prev_compl_frame(csf) ;
return compl_subgoal_ptr(csf) ;
}
static void ReclaimDSandMarkReset(th_context *th, VariantSF to, int leader)
{
CPtr csf = openreg ;
for(;;)
{ if( !is_completed(compl_subgoal_ptr(csf)))
/* Handle early completion */
{ subg_grabbed(compl_subgoal_ptr(csf)) = TRUE ;
subg_tid(compl_subgoal_ptr(csf)) = leader ;
subg_asf_list_ptr(compl_subgoal_ptr(csf)) = NULL;
subg_compl_susp_ptr(compl_subgoal_ptr(csf)) = NULL;
}
if( compl_subgoal_ptr(csf) == to )
break;
csf = prev_compl_frame(csf) ;
}
}
int count_sccs(CTXTdecl) {
int ctr = 0;
int last_scc = 0;
CPtr csf = openreg;
// printf("open %x COMPL %x\n",openreg,COMPLSTACKBOTTOM);
while (csf < COMPLSTACKBOTTOM) {
// printf("comp level %d\n",compl_level(csf));
if (compl_level(csf) != last_scc) {
ctr++;
last_scc = compl_level(csf);
// printf("ctr: %d\n",ctr);
}
csf = prev_compl_frame(csf);
}
return ctr;
}
static void reset_thread( th_context *th, th_context *ctxt, VariantSF sgf,
VariantSF *resetsgf )
{
CPtr tbreg ;
/* if the subgoal is not being computed by this thread,
because meanwhile it has been grabbed by another thread,
nothing should be done */
if( subg_tid(sgf) != ctxt->tid )
{
*resetsgf = ctxt->waiting_for_subgoal;
return ;
}
sgf = bottom_leader(ctxt, sgf) ;
*resetsgf = sgf ;
#ifdef WIN_NT
ReclaimDSandMarkReset(ctxt, sgf, xsb_thread_id);
#else
ReclaimDSandMarkReset(ctxt, sgf, (pthread_t) xsb_thread_id);
#endif
/* trick to use other thread's context */
th = ctxt ;
/* reset the stacks by restoring the generator cp of this sg */
breg = subg_cp_ptr(sgf) ;
tbreg = breg ;
openreg = prev_compl_frame(subg_compl_stack_ptr(sgf)) ;
switch_envs(tbreg);
ptcpreg = tcp_ptcp(tbreg);
delayreg = tcp_pdreg(tbreg);
reclaim_stacks(tbreg) ;
restore_some_wamregs(tbreg, ereg);
/* restore_trail_condition_registers */
ebreg = cp_ebreg(tcp_prevbreg(tbreg));
hbreg = cp_hreg(tcp_prevbreg(tbreg));
pcreg = (byte *)tcp_reset_pcreg(tbreg) ;
table_restore_registers(tbreg, pcreg[3], reg);
/* delete the generator cp */
breg = tcp_prevbreg(breg) ;
ctxt->reset_thread = TRUE;
}
