private static int OptimizeSets(ATN atn, bool preserveOrder) { if (preserveOrder) { // this optimization currently doesn't preserve edge order. return 0; } int removedPaths = 0; IList<DecisionState> decisions = atn.decisionToState; foreach (DecisionState decision in decisions) { IntervalSet setTransitions = new IntervalSet(); for (int i = 0; i < decision.NumberOfOptimizedTransitions; i++) { Transition epsTransition = decision.GetOptimizedTransition(i); if (!(epsTransition is EpsilonTransition)) { continue; } if (epsTransition.target.NumberOfOptimizedTransitions != 1) { continue; } Transition transition = epsTransition.target.GetOptimizedTransition(0); if (!(transition.target is BlockEndState)) { continue; } if (transition is NotSetTransition) { // TODO: not yet implemented continue; } if (transition is AtomTransition || transition is RangeTransition || transition is SetTransition) { setTransitions.Add(i); } } if (setTransitions.Count <= 1) { continue; } IList<Transition> optimizedTransitions = new List<Transition>(); for (int i_1 = 0; i_1 < decision.NumberOfOptimizedTransitions; i_1++) { if (!setTransitions.Contains(i_1)) { optimizedTransitions.Add(decision.GetOptimizedTransition(i_1)); } } ATNState blockEndState = decision.GetOptimizedTransition(setTransitions.MinElement).target.GetOptimizedTransition(0).target; IntervalSet matchSet = new IntervalSet(); for (int i_2 = 0; i_2 < setTransitions.GetIntervals().Count; i_2++) { Interval interval = setTransitions.GetIntervals()[i_2]; for (int j = interval.a; j <= interval.b; j++) { Transition matchTransition = decision.GetOptimizedTransition(j).target.GetOptimizedTransition(0); if (matchTransition is NotSetTransition) { throw new NotSupportedException("Not yet implemented."); } else { matchSet.AddAll(matchTransition.Label); } } } Transition newTransition; if (matchSet.GetIntervals().Count == 1) { if (matchSet.Count == 1) { newTransition = new AtomTransition(blockEndState, matchSet.MinElement); } else { Interval matchInterval = matchSet.GetIntervals()[0]; newTransition = new RangeTransition(blockEndState, matchInterval.a, matchInterval.b); } } else { newTransition = new SetTransition(blockEndState, matchSet); } ATNState setOptimizedState = new BasicState(); setOptimizedState.SetRuleIndex(decision.ruleIndex); atn.AddState(setOptimizedState); setOptimizedState.AddTransition(newTransition); optimizedTransitions.Add(new EpsilonTransition(setOptimizedState)); removedPaths += decision.NumberOfOptimizedTransitions - optimizedTransitions.Count; if (decision.IsOptimized) { while (decision.NumberOfOptimizedTransitions > 0) { decision.RemoveOptimizedTransition(decision.NumberOfOptimizedTransitions - 1); } } foreach (Transition transition_1 in optimizedTransitions) { decision.AddOptimizedTransition(transition_1); } } return removedPaths; }
private static int OptimizeSets(ATN atn, bool preserveOrder) { if (preserveOrder) { // this optimization currently doesn't preserve edge order. return(0); } int removedPaths = 0; IList <DecisionState> decisions = atn.decisionToState; foreach (DecisionState decision in decisions) { IntervalSet setTransitions = new IntervalSet(); for (int i = 0; i < decision.NumberOfOptimizedTransitions; i++) { Transition epsTransition = decision.GetOptimizedTransition(i); if (!(epsTransition is EpsilonTransition)) { continue; } if (epsTransition.target.NumberOfOptimizedTransitions != 1) { continue; } Transition transition = epsTransition.target.GetOptimizedTransition(0); if (!(transition.target is BlockEndState)) { continue; } if (transition is NotSetTransition) { // TODO: not yet implemented continue; } if (transition is AtomTransition || transition is RangeTransition || transition is SetTransition) { setTransitions.Add(i); } } if (setTransitions.Count <= 1) { continue; } IList <Transition> optimizedTransitions = new List <Transition>(); for (int i_1 = 0; i_1 < decision.NumberOfOptimizedTransitions; i_1++) { if (!setTransitions.Contains(i_1)) { optimizedTransitions.Add(decision.GetOptimizedTransition(i_1)); } } ATNState blockEndState = decision.GetOptimizedTransition(setTransitions.MinElement).target.GetOptimizedTransition(0).target; IntervalSet matchSet = new IntervalSet(); for (int i_2 = 0; i_2 < setTransitions.GetIntervals().Count; i_2++) { Interval interval = setTransitions.GetIntervals()[i_2]; for (int j = interval.a; j <= interval.b; j++) { Transition matchTransition = decision.GetOptimizedTransition(j).target.GetOptimizedTransition(0); if (matchTransition is NotSetTransition) { throw new NotSupportedException("Not yet implemented."); } else { matchSet.AddAll(matchTransition.Label); } } } Transition newTransition; if (matchSet.GetIntervals().Count == 1) { if (matchSet.Count == 1) { newTransition = new AtomTransition(blockEndState, matchSet.MinElement); } else { Interval matchInterval = matchSet.GetIntervals()[0]; newTransition = new RangeTransition(blockEndState, matchInterval.a, matchInterval.b); } } else { newTransition = new SetTransition(blockEndState, matchSet); } ATNState setOptimizedState = new BasicState(); setOptimizedState.SetRuleIndex(decision.ruleIndex); atn.AddState(setOptimizedState); setOptimizedState.AddTransition(newTransition); optimizedTransitions.Add(new EpsilonTransition(setOptimizedState)); removedPaths += decision.NumberOfOptimizedTransitions - optimizedTransitions.Count; if (decision.IsOptimized) { while (decision.NumberOfOptimizedTransitions > 0) { decision.RemoveOptimizedTransition(decision.NumberOfOptimizedTransitions - 1); } } foreach (Transition transition_1 in optimizedTransitions) { decision.AddOptimizedTransition(transition_1); } } return(removedPaths); }
private static void OptimizeSets(Grammar g, ATN atn) { if (g.IsParser()) { // parser codegen doesn't currently support SetTransition return; } int removedStates = 0; IList<DecisionState> decisions = atn.decisionToState; foreach (DecisionState decision in decisions) { if (decision.ruleIndex >= 0) { Rule rule = g.GetRule(decision.ruleIndex); if (char.IsLower(rule.name[0])) { // parser codegen doesn't currently support SetTransition continue; } } IntervalSet setTransitions = new IntervalSet(); for (int i = 0; i < decision.NumberOfTransitions; i++) { Transition epsTransition = decision.Transition(i); if (!(epsTransition is EpsilonTransition)) { continue; } if (epsTransition.target.NumberOfTransitions != 1) { continue; } Transition transition = epsTransition.target.Transition(0); if (!(transition.target is BlockEndState)) { continue; } if (transition is NotSetTransition) { // TODO: not yet implemented continue; } if (transition is AtomTransition || transition is RangeTransition || transition is SetTransition) { setTransitions.Add(i); } } // due to min alt resolution policies, can only collapse sequential alts for (int i = setTransitions.GetIntervals().Count - 1; i >= 0; i--) { Interval interval = setTransitions.GetIntervals()[i]; if (interval.Length <= 1) { continue; } ATNState blockEndState = decision.Transition(interval.a).target.Transition(0).target; IntervalSet matchSet = new IntervalSet(); for (int j = interval.a; j <= interval.b; j++) { Transition matchTransition = decision.Transition(j).target.Transition(0); if (matchTransition is NotSetTransition) { throw new NotImplementedException(); } IntervalSet set = matchTransition.Label; int minElem = set.MinElement; int maxElem = set.MaxElement; for (int k = minElem; k <= maxElem; k++) { if (matchSet.Contains(k)) { char setMin = (char)set.MinElement; char setMax = (char)set.MaxElement; // TODO: Token is missing (i.e. position in source will not be displayed). g.tool.errMgr.GrammarError(ErrorType.CHARACTERS_COLLISION_IN_SET, g.fileName, null, (char)minElem + "-" + (char)maxElem, "[" + setMin + "-" + setMax + "]"); break; } } matchSet.AddAll(set); } Transition newTransition; if (matchSet.GetIntervals().Count == 1) { if (matchSet.Count == 1) { newTransition = new AtomTransition(blockEndState, matchSet.MinElement); } else { Interval matchInterval = matchSet.GetIntervals()[0]; newTransition = new RangeTransition(blockEndState, matchInterval.a, matchInterval.b); } } else { newTransition = new SetTransition(blockEndState, matchSet); } decision.Transition(interval.a).target.SetTransition(0, newTransition); for (int j = interval.a + 1; j <= interval.b; j++) { Transition removed = decision.Transition(interval.a + 1); decision.RemoveTransition(interval.a + 1); atn.RemoveState(removed.target); removedStates++; } } } //System.Console.WriteLine("ATN optimizer removed " + removedStates + " states by collapsing sets."); }