/** * given a DelayabilityAnalysis and the computations of each unit, calculates the latest * computation-point for each expression.<br> * the <code>equivRhsMap</code> could be calculated on the fly, but it is <b>very</b> likely that * it already exists (as similar maps are used for calculating Earliestness, Delayed,...<br> * the shared set allows more efficient set-operations, when they the computation is merged with * other analyses/computations. * * @param dg a ExceptionalUnitGraph * @param delayed the delayability-analysis of the same graph. * @param equivRhsMap all computations of the graph * @param set the shared flowSet */ public LatestComputation( UnitGraph unitGraph, DelayabilityAnalysis delayed, Map equivRhsMap, BoundedFlowSet set) { unitToLatest = new HashMap<Unit, FlowSet>(unitGraph.size() + 1, 0.7f); Iterator unitIt = unitGraph.iterator(); while (unitIt.hasNext()) { /* create a new Earliest-list for each unit */ Unit currentUnit = (Unit) unitIt.next(); /* basically the latest-set is: * (delayed) INTERSECT (comp UNION (UNION_successors ~Delayed)) = * (delayed) MINUS ((INTERSECTION_successors Delayed) MINUS comp). */ FlowSet delaySet = (FlowSet) delayed.getFlowBefore(currentUnit); /* Calculate (INTERSECTION_successors Delayed) */ FlowSet succCompSet = (FlowSet) set.topSet(); List succList = unitGraph.getSuccsOf(currentUnit); Iterator succIt = succList.iterator(); while (succIt.hasNext()) { Unit successor = (Unit) succIt.next(); succCompSet.intersection((FlowSet) delayed.getFlowBefore(successor), succCompSet); } /* remove the computation of this set: succCompSet is then: * ((INTERSECTION_successors Delayed) MINUS comp) */ if (equivRhsMap.get(currentUnit) != null) succCompSet.remove(equivRhsMap.get(currentUnit)); /* make the difference: */ FlowSet latest = (FlowSet) delaySet.emptySet(); delaySet.difference(succCompSet, latest); unitToLatest.put(currentUnit, latest); } }
protected void flowThrough(Object inValue, Object unit, Object outValue) { FlowSet in = (FlowSet) inValue, out = (FlowSet) outValue; // Perform kill in.difference(unitToKillSet.get(unit), out); // Perform generation out.union(unitToGenerateSet.get(unit), out); }