/**
* Construct the propagation links
*/
function FindLinks()
{
/* Housekeeping detail:
** Add to every propagate link a pointer back to the state to
** which the link is attached. */
foreach ($this->sorted as $info) {
$info->key->stp = $info->data;
}
/* Convert all backlinks into forward links. Only the forward
** links are used in the follow-set computation. */
for ($i = 0; $i < $this->nstate; $i++) {
$stp = $this->sorted[$i];
for ($cfp = $stp->data->cfp; $cfp; $cfp = $cfp->next) {
for ($plp = $cfp->bplp; $plp; $plp = $plp->next) {
$other = $plp->cfp;
PHP_ParserGenerator_PropagationLink::Plink_add($other->fplp, $cfp);
}
}
}
}
/**
* Compute the closure of the configuration list.
*
* This calculates all of the possible continuations of
* each configuration, ensuring that each state accounts
* for every configuration that could arrive at that state.
*/
public static function Configlist_closure(PHP_ParserGenerator_Data $lemp)
{
for ($cfp = self::$current; $cfp; $cfp = $cfp->next) {
$rp = $cfp->rp;
$dot = $cfp->dot;
if ($dot >= $rp->nrhs) {
continue;
}
$sp = $rp->rhs[$dot];
if ($sp->type == PHP_ParserGenerator_Symbol::NONTERMINAL) {
if ($sp->rule === 0 && $sp !== $lemp->errsym) {
PHP_ParserGenerator::ErrorMsg($lemp->filename, $rp->line, "Nonterminal \"%s\" has no rules.", $sp->name);
$lemp->errorcnt++;
}
for ($newrp = $sp->rule; $newrp; $newrp = $newrp->nextlhs) {
$newcfp = self::Configlist_add($newrp, 0);
for ($i = $dot + 1; $i < $rp->nrhs; $i++) {
$xsp = $rp->rhs[$i];
if ($xsp->type == PHP_ParserGenerator_Symbol::TERMINAL) {
$newcfp->fws[$xsp->index] = 1;
break;
} elseif ($xsp->type == PHP_ParserGenerator_Symbol::MULTITERMINAL) {
for ($k = 0; $k < $xsp->nsubsym; $k++) {
$newcfp->fws[$xsp->subsym[$k]->index] = 1;
}
break;
} else {
$a = array_diff_key($xsp->firstset, $newcfp->fws);
$newcfp->fws += $a;
if ($xsp->lambda === false) {
break;
}
}
}
if ($i == $rp->nrhs) {
PHP_ParserGenerator_PropagationLink::Plink_add($cfp->fplp, $newcfp);
}
}
}
}
}
