public function process(GraphState $state)
{
$graph = $state->getGraph();
$vars = Helper::findVariables($graph);
$postdominator = $state->getPostDominator();
$dominator = $state->getDominator();
foreach ($vars as $var) {
$usages = [];
foreach ($graph->vertices() as $vertex) {
if (in_array($var, $vertex->getVariables(), true)) {
$usages[] = $vertex;
}
}
$dom = $postdominator->immediateDominatorArray($usages);
while ($dom) {
foreach ($usages as $usage) {
if ($dominator->strictlyDominates($usage, $dom)) {
$dom = $postdominator->immediateDominator($dom);
continue 2;
}
}
break;
}
if (!$dom) {
continue;
}
if ($dom instanceof Jump || $dom instanceof JumpZ) {
Helper::insertBefore($dom, new Free($var), $graph);
} else {
Helper::insertAfter($dom, new Free($var), $graph);
}
}
}
