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added D2 as dup temp of D state. almost ready to change position of addDFAState

This commit is contained in:
Terence Parr 2012-07-30 22:15:09 -07:00
parent c893f2af08
commit 85ea296632
2 changed files with 39 additions and 13 deletions
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49
runtime/Java/src/org/antlr/v4/runtime/atn/ParserATNSimulator.java
View File

@ -476,6 +476,7 @@ public class ParserATNSimulator<Symbol extends Token> extends ATNSimulator {
ATN_failover++;
ATNConfigSet previous = s0.configs;
DFAState previousD = s0;
DFAState D;
ATNConfigSet fullCtxSet;
@ -505,15 +506,23 @@ public class ParserATNSimulator<Symbol extends Token> extends ATNSimulator {
// will get error no matter what.
throw noViableAlt(input, outerContext, previous, startIndex);
}
DFAState D2 = new DFAState(reach);
// if ( dfa.states.get(previousD)==null ) { always ok it seems; previousD always exists
// System.err.println("-----------------------------------------");
// }
D = addDFAEdge(dfa, previous, t, reach); // always adding edge even if to a conflict state
int predictedAlt = getUniqueAlt(reach);
if ( predictedAlt!=ATN.INVALID_ALT_NUMBER ) {
D.isAcceptState = true;
D.configs.uniqueAlt = predictedAlt;
D.prediction = predictedAlt;
D2.isAcceptState = true;
D2.configs.uniqueAlt = predictedAlt;
D2.prediction = predictedAlt;
}
else {
D.configs.conflictingAlts = getConflictingAlts(reach, false);
D2.configs.conflictingAlts = D.configs.conflictingAlts;
if ( D.configs.conflictingAlts!=null ) {
if ( greedy ) {
// int k = input.index() - startIndex + 1; // how much input we used
@ -527,16 +536,12 @@ public class ParserATNSimulator<Symbol extends Token> extends ATNSimulator {
D.configs.conflictingAlts, D.configs);
}
D.isAcceptState = true;
D2.isAcceptState = true;
predictedAlt = resolveToMinAlt(D, D.configs.conflictingAlts);
}
else {
if ( debug ) System.out.println("RETRY with outerContext="+outerContext);
PredictionContext predictionCtx = PredictionContext.fromRuleContext(outerContext);
predictionCtx = getCachedContext(predictionCtx);
Integer predI = D.contextToPredictedAlt.get(predictionCtx);
if ( predI!=null ) {
return predI;
}
// don't look up context in cache now since we're just creating state D
loopsSimulateTailRecursion = true;
ATNConfigSet s0_closure =
computeStartState(dfa.atnStartState,
@ -551,9 +556,17 @@ public class ParserATNSimulator<Symbol extends Token> extends ATNSimulator {
D.configs.conflictingAlts.getMinElement(),
greedy);
// not accept state: isCtxSensitive
PredictionContext predictionCtx = PredictionContext.fromRuleContext(outerContext);
predictionCtx = getCachedContext(predictionCtx);
D.isCtxSensitive = true; // always force DFA to ATN simulate
D.prediction = predictedAlt = fullCtxSet.uniqueAlt;
D.prediction = predictedAlt = fullCtxSet.uniqueAlt; // TODO: why set prediction?
D.prediction = ATN.INVALID_ALT_NUMBER;
D.contextToPredictedAlt.put(predictionCtx, predictedAlt);
D2.isCtxSensitive = true; // always force DFA to ATN simulate
D2.prediction = predictedAlt = fullCtxSet.uniqueAlt; // TODO: why set prediction?
D2.prediction = ATN.INVALID_ALT_NUMBER;
D2.contextToPredictedAlt.put(predictionCtx, predictedAlt);
//addDFAEdge(dfa, previous, t, reach);
return predictedAlt; // all done with preds, etc...
}
}
@ -564,6 +577,8 @@ public class ParserATNSimulator<Symbol extends Token> extends ATNSimulator {
int exitAlt = 2;
D.isAcceptState = true; // when ambig or ctx sens or nongreedy or .* loop hitting rule stop
D.prediction = predictedAlt = exitAlt;
D2.isAcceptState = true; // when ambig or ctx sens or nongreedy or .* loop hitting rule stop
D2.prediction = predictedAlt = exitAlt;
}
}
}
@ -575,12 +590,16 @@ public class ParserATNSimulator<Symbol extends Token> extends ATNSimulator {
// reaches end via .* means nothing after.
D.isAcceptState = true;
D.prediction = predictedAlt = exitAlt;
D2.isAcceptState = true;
D2.prediction = predictedAlt = exitAlt;
}
else {// if we reached end of rule via exit branch and decision nongreedy, we matched
if ( configWithAltAtStopState(reach, exitAlt) ) {
if ( debug ) System.out.println("nongreedy at stop state for exit branch");
D.isAcceptState = true;
D.prediction = predictedAlt = exitAlt;
D2.isAcceptState = true;
D2.prediction = predictedAlt = exitAlt;
}
}
}
@ -596,7 +615,9 @@ public class ParserATNSimulator<Symbol extends Token> extends ATNSimulator {
int stopIndex = input.index();
input.seek(startIndex);
IntervalSet alts = evalSemanticContext(predPredictions, outerContext, true);
D.prediction = ATN.INVALID_ALT_NUMBER;
D.prediction = ATN.INVALID_ALT_NUMBER; // indicate we have preds
D2.prediction = ATN.INVALID_ALT_NUMBER;
//addDFAEdge(dfa, previous, t, reach);
switch (alts.size()) {
case 0:
throw noViableAlt(input, outerContext, D.configs, startIndex);
@ -614,9 +635,11 @@ public class ParserATNSimulator<Symbol extends Token> extends ATNSimulator {
}
}
//addDFAEdge(dfa, previous, t, reach);
if ( D.isAcceptState ) return predictedAlt;
previous = reach;
previousD = D;
input.consume();
t = input.LA(1);
}
@ -885,8 +908,7 @@ public class ParserATNSimulator<Symbol extends Token> extends ATNSimulator {
{
IntervalSet predictions = new IntervalSet();
for (DFAState.PredPrediction pair : predPredictions) {
if ( pair.pred==null ) {
System.err.println("EEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEE");
if ( pair.pred==null ) { // TODO: can't be null, can it?
predictions.add(pair.alt);
if (!complete) {
break;
@ -1233,8 +1255,9 @@ public class ParserATNSimulator<Symbol extends Token> extends ATNSimulator {
Regardless of what goes on for the other states, this is
sufficient to force us to add this new state to the ATN-to-DFA work list.
TODO: split into "has nonconflict config--add to work list" and getambigalts
functions
TODO: split into "has nonconflict config--add to work list" and getambigalts functions
TODO: now we know contexts are merged, can we optimize? Use big int -> config array?
*/
@Nullable
public IntervalSet getConflictingAlts(@NotNull ATNConfigSet configs, boolean fullCtx) {
@ -1448,6 +1471,8 @@ public class ParserATNSimulator<Symbol extends Token> extends ATNSimulator {
int t,
@NotNull ATNConfigSet q)
{
// TODO: how can from ever be new? oh, the first time into execATN;
// wait: shouldn't that be s0
DFAState from = addDFAState(dfa, p);
DFAState to = addDFAState(dfa, q);
if ( debug ) System.out.println("EDGE "+from+" -> "+to+" upon "+getTokenName(t));

3
runtime/Java/src/org/antlr/v4/runtime/dfa/DFAState.java
View File

@ -77,7 +77,8 @@ public class DFAState {
public boolean isAcceptState = false;
/** if accept state, what ttype do we match or alt do we predict?
* This is set to ATN.INVALID_ALT_NUMBER when predicates!=null.
* This is set to ATN.INVALID_ALT_NUMBER when predicates!=null or
* isCtxSensitive.
*/
public int prediction;