DFAState s,
int k)
{
//System.out.println("walk "+s.stateNumber+" in dfa for decision "+dfa.decisionNumber);
if ( s.isAcceptState() ) {
ST dfaST = templates.getInstanceOf("dfaAcceptState");
dfaST.add("alt", Utils.integer(s.getUniquelyPredictedAlt()));
return dfaST;
}
// the default templates for generating a state and its edges
// can be an if-then-else structure or a switch
String dfaStateName = "dfaState";
String dfaLoopbackStateName = "dfaLoopbackState";
String dfaOptionalBlockStateName = "dfaOptionalBlockState";
String dfaEdgeName = "dfaEdge";
if ( parentGenerator.canGenerateSwitch(s) ) {
dfaStateName = "dfaStateSwitch";
dfaLoopbackStateName = "dfaLoopbackStateSwitch";
dfaOptionalBlockStateName = "dfaOptionalBlockStateSwitch";
dfaEdgeName = "dfaEdgeSwitch";
}
ST dfaST = templates.getInstanceOf(dfaStateName);
if ( dfa.getNFADecisionStartState().decisionStateType==NFAState.LOOPBACK ) {
dfaST = templates.getInstanceOf(dfaLoopbackStateName);
}
else if ( dfa.getNFADecisionStartState().decisionStateType==NFAState.OPTIONAL_BLOCK_START ) {
dfaST = templates.getInstanceOf(dfaOptionalBlockStateName);
}
dfaST.add("k", Utils.integer(k));
dfaST.add("stateNumber", Utils.integer(s.stateNumber));
dfaST.add("semPredState", s.isResolvedWithPredicates());
/*
String description = dfa.getNFADecisionStartState().getDescription();
description = parentGenerator.target.getTargetStringLiteralFromString(description);
//System.out.println("DFA: "+description+" associated with AST "+dfa.getNFADecisionStartState());
if ( description!=null ) {
dfaST.add("description", description);
}
*/
int EOTPredicts = NFA.INVALID_ALT_NUMBER;
DFAState EOTTarget = null;
//System.out.println("DFA state "+s.stateNumber);
for (int i = 0; i < s.getNumberOfTransitions(); i++) {
Transition edge = s.transition(i);
//System.out.println("edge "+s.stateNumber+"-"+edge.label.toString()+"->"+edge.target.stateNumber);
if ( edge.label.getAtom()==Label.EOT ) {
// don't generate a real edge for EOT; track alt EOT predicts
// generate that prediction in the else clause as default case
EOTTarget = (DFAState)edge.target;
EOTPredicts = EOTTarget.getUniquelyPredictedAlt();
/*
System.out.println("DFA s"+s.stateNumber+" EOT goes to s"+
edge.target.stateNumber+" predicates alt "+
EOTPredicts);
*/
continue;
}
ST edgeST = templates.getInstanceOf(dfaEdgeName);
// If the template wants all the label values delineated, do that
if ( edgeST.impl.formalArguments.get("labels")!=null ) {
List<Integer> labels = edge.label.getSet().toList();
List<String> targetLabels = new ArrayList<String>(labels.size());
for (int j = 0; j < labels.size(); j++) {
Integer vI = labels.get(j);
String label =
parentGenerator.getTokenTypeAsTargetLabel(vI);
targetLabels.add(label); // rewrite List element to be name
}
edgeST.add("labels", targetLabels);
}
else { // else create an expression to evaluate (the general case)
edgeST.add("labelExpr",
parentGenerator.genLabelExpr(templates,edge,k));
}
// stick in any gated predicates for any edge if not already a pred
if ( !edge.label.isSemanticPredicate() ) {
DFAState target = (DFAState)edge.target;
SemanticContext preds =
target.getGatedPredicatesInNFAConfigurations();
if ( preds!=null ) {
//System.out.println("preds="+target.getGatedPredicatesInNFAConfigurations());
ST predST = preds.genExpr(parentGenerator,
parentGenerator.getTemplates(),
dfa);
edgeST.add("predicates", predST);
}
}
ST targetST =
walkFixedDFAGeneratingStateMachine(templates,
dfa,
(DFAState)edge.target,
k+1);
edgeST.add("targetState", targetST);
dfaST.add("edges", edgeST);
/*
System.out.println("back to DFA "+
dfa.decisionNumber+"."+s.stateNumber);
*/
}
// HANDLE EOT EDGE
if ( EOTPredicts!=NFA.INVALID_ALT_NUMBER ) {
// EOT unique predicts an alt
dfaST.add("eotPredictsAlt", Utils.integer(EOTPredicts));
}
else if ( EOTTarget!=null && EOTTarget.getNumberOfTransitions()>0 ) {
// EOT state has transitions so must split on predicates.
// Generate predicate else-if clauses and then generate
// NoViableAlt exception as else clause.
// Note: these predicates emanate from the EOT target state
// rather than the current DFAState s so the error message
// might be slightly misleading if you are looking at the
// state number. Predicates emanating from EOT targets are
// hoisted up to the state that has the EOT edge.
for (int i = 0; i < EOTTarget.getNumberOfTransitions(); i++) {
Transition predEdge = EOTTarget.transition(i);
ST edgeST = templates.getInstanceOf(dfaEdgeName);
edgeST.add("labelExpr",
parentGenerator.genSemanticPredicateExpr(templates,predEdge));
// the target must be an accept state
//System.out.println("EOT edge");
ST targetST =
walkFixedDFAGeneratingStateMachine(templates,
dfa,
(DFAState)predEdge.target,
k+1);
edgeST.add("targetState", targetST);