예제 #1
0
        public static IList <MatchInfo> genFirstSet(IList <MatchInfo> partialMatches, Expansion exp)
        {
            if (exp is RegularExpression)
            {
                IList <MatchInfo> retval = new List <MatchInfo>();
                for (int i = 0; i < partialMatches.Count; i++)
                {
                    MatchInfo m    = (MatchInfo)partialMatches[i];
                    MatchInfo mnew = new MatchInfo();
                    for (int j = 0; j < m.firstFreeLoc; j++)
                    {
                        mnew.match[j] = m.match[j];
                    }
                    mnew.firstFreeLoc = m.firstFreeLoc;
                    mnew.match[mnew.firstFreeLoc++] = ((RegularExpression)exp).Ordinal;
                    if (mnew.firstFreeLoc == MatchInfo.laLimit)
                    {
                        sizeLimitedMatches.Add(mnew);
                    }
                    else
                    {
                        retval.Add(mnew);
                    }
                }
                return(retval);
            }
            else if (exp is NonTerminal)
            {
                NormalProduction prod = ((NonTerminal)exp).Production;
                if (prod is CodeProduction)
                {
                    return(new List <MatchInfo>());
                }
                else
                {
                    return(genFirstSet(partialMatches, prod.Expansion));
                }
            }
            else if (exp is Choice)
            {
                IList <MatchInfo> retval = new List <MatchInfo>();
                Choice            ch     = (Choice)exp;
                foreach (Expansion e in ch.Choices)
                {
                    IList <MatchInfo> v = genFirstSet(partialMatches, e);
                    listAppend(retval, v);
                }
                return(retval);
            }
            else if (exp is Sequence)
            {
                IList <MatchInfo> v   = partialMatches;
                Sequence          seq = (Sequence)exp;
                foreach (Expansion unit in seq.Units)
                {
                    v = genFirstSet(v, unit);
                    if (v.Count == 0)
                    {
                        break;
                    }
                }
                return(v);
            }
            else if (exp is OneOrMore)
            {
                IList <MatchInfo> retval = new List <MatchInfo>();
                IList <MatchInfo> v      = partialMatches;
                OneOrMore         om     = (OneOrMore)exp;
                while (true)
                {
                    v = genFirstSet(v, om.Expansion);
                    if (v.Count == 0)
                    {
                        break;
                    }

                    listAppend(retval, v);
                }
                return(retval);
            }
            else if (exp is ZeroOrMore)
            {
                IList <MatchInfo> retval = new List <MatchInfo>();
                listAppend(retval, partialMatches);
                IList <MatchInfo> v  = partialMatches;
                ZeroOrMore        zm = (ZeroOrMore)exp;
                while (true)
                {
                    v = genFirstSet(v, zm.Expansion);
                    if (v.Count == 0)
                    {
                        break;
                    }

                    listAppend(retval, v);
                }
                return(retval);
            }
            else if (exp is ZeroOrOne)
            {
                IList <MatchInfo> retval = new List <MatchInfo>();
                listAppend(retval, partialMatches);
                listAppend(retval, genFirstSet(partialMatches, ((ZeroOrOne)exp).Expansion));
                return(retval);
            }
            else if (exp is TryBlock)
            {
                return(genFirstSet(partialMatches, ((TryBlock)exp).Expansion));
            }
            else if (considerSemanticLA &&
                     exp is Lookahead &&
                     ((Lookahead)exp).ActionTokens.Count != 0
                     )
            {
                return(new List <MatchInfo>());
            }
            else
            {
                IList <MatchInfo> retval = new List <MatchInfo>();
                listAppend(retval, partialMatches);
                return(retval);
            }
        }
예제 #2
0
 private static String image(MatchInfo m)
 {
     String ret = "";
     for (int i = 0; i < m.firstFreeLoc; i++) {
         if (m.match[i] == 0) {
             ret += " <EOF>";
         } else {
             RegularExpression re = (RegularExpression) CSharpCCGlobals.rexps_of_tokens[m.match[i]];
             if (re is RStringLiteral) {
                 ret += " \"" + CSharpCCGlobals.AddEscapes(((RStringLiteral) re).Image) + "\"";
             } else if (re.Label != null && !re.Label.Equals("")) {
                 ret += " <" + re.Label + ">";
             } else {
                 ret += " <token of kind " + i + ">";
             }
         }
     }
     if (m.firstFreeLoc == 0) {
         return "";
     } else {
         return ret.Substring(1);
     }
 }
예제 #3
0
 public static void choiceCalc(Choice choice)
 {
     int first = firstChoice(choice);
     // dbl[i] and dbr[i] are lists of size limited matches for choice i
     // of choice.  dbl ignores matches with semantic lookaheads (when force_la_check
     // is false), while dbr ignores semantic lookahead.
     IList<MatchInfo>[] dbl = new IList<MatchInfo>[choice.Choices.Count];
     IList<MatchInfo>[] dbr = new IList<MatchInfo>[choice.Choices.Count];
     int[] minLA = new int[choice.Choices.Count - 1];
     MatchInfo[] overlapInfo = new MatchInfo[choice.Choices.Count - 1];
     int[] other = new int[choice.Choices.Count - 1];
     MatchInfo m;
     IList<MatchInfo> v;
     bool overlapDetected;
     for (int la = 1; la <= Options.getChoiceAmbiguityCheck(); la++) {
         MatchInfo.laLimit = la;
         LookaheadWalk.considerSemanticLA = !Options.getForceLaCheck();
         for (int i = first; i < choice.Choices.Count - 1; i++) {
             LookaheadWalk.sizeLimitedMatches = new List<MatchInfo>();
             m = new MatchInfo();
             m.firstFreeLoc = 0;
             v = new List<MatchInfo>();
             v.Add(m);
             LookaheadWalk.genFirstSet(v, (Expansion) choice.Choices[i]);
             dbl[i] = LookaheadWalk.sizeLimitedMatches;
         }
         LookaheadWalk.considerSemanticLA = false;
         for (int i = first + 1; i < choice.Choices.Count; i++) {
             LookaheadWalk.sizeLimitedMatches = new List<MatchInfo>();
             m = new MatchInfo();
             m.firstFreeLoc = 0;
             v = new List<MatchInfo>();
             v.Add(m);
             LookaheadWalk.genFirstSet(v, (Expansion) choice.Choices[i]);
             dbr[i] = LookaheadWalk.sizeLimitedMatches;
         }
         if (la == 1) {
             for (int i = first; i < choice.Choices.Count - 1; i++) {
                 Expansion exp = (Expansion) choice.Choices[i];
                 if (Semanticize.EmptyExpansionExists(exp)) {
                     CSharpCCErrors.Warning(exp,
                         "This choice can expand to the empty token sequence " +
                         "and will therefore always be taken in favor of the choices appearing later.");
                     break;
                 } else if (CodeCheck(dbl[i])) {
                     CSharpCCErrors.Warning(exp,
                         "CSHARPCODE non-terminal will force this choice to be taken " +
                         "in favor of the choices appearing later.");
                     break;
                 }
             }
         }
         overlapDetected = false;
         for (int i = first; i < choice.Choices.Count - 1; i++) {
             for (int j = i + 1; j < choice.Choices.Count; j++) {
                 if ((m = overlap(dbl[i], dbr[j])) != null) {
                     minLA[i] = la + 1;
                     overlapInfo[i] = m;
                     other[i] = j;
                     overlapDetected = true;
                     break;
                 }
             }
         }
         if (!overlapDetected) {
             break;
         }
     }
     for (int i = first; i < choice.Choices.Count - 1; i++) {
         if (explicitLA((Expansion) choice.Choices[i]) && !Options.getForceLaCheck()) {
             continue;
         }
         if (minLA[i] > Options.getChoiceAmbiguityCheck()) {
             CSharpCCErrors.Warning("Choice conflict involving two expansions at");
             Console.Error.Write("         line " + ((Expansion) choice.Choices[i]).Line);
             Console.Error.Write(", column " + ((Expansion) choice.Choices[i]).Column);
             Console.Error.Write(" and line " + ((Expansion) choice.Choices[other[i]]).Line);
             Console.Error.Write(", column " + ((Expansion) choice.Choices[other[i]]).Column);
             Console.Error.WriteLine(" respectively.");
             Console.Error.WriteLine("         A common prefix is: " + image(overlapInfo[i]));
             Console.Error.WriteLine("         Consider using a lookahead of " + minLA[i] + " or more for earlier expansion.");
         } else if (minLA[i] > 1) {
             CSharpCCErrors.Warning("Choice conflict involving two expansions at");
             Console.Error.Write("         line " + ((Expansion) choice.Choices[i]).Line);
             Console.Error.Write(", column " + ((Expansion) choice.Choices[i]).Column);
             Console.Error.Write(" and line " + ((Expansion) choice.Choices[other[i]]).Line);
             Console.Error.Write(", column " + ((Expansion) choice.Choices[other[i]]).Column);
             Console.Error.WriteLine(" respectively.");
             Console.Error.WriteLine("         A common prefix is: " + image(overlapInfo[i]));
             Console.Error.WriteLine("         Consider using a lookahead of " + minLA[i] + " for earlier expansion.");
         }
     }
 }
예제 #4
0
 public static void ebnfCalc(Expansion exp, Expansion nested)
 {
     // exp is one of OneOrMore, ZeroOrMore, ZeroOrOne
     MatchInfo m, m1 = null;
     IList<MatchInfo> v, first, follow;
     int la;
     for (la = 1; la <= Options.getOtherAmbiguityCheck(); la++) {
         MatchInfo.laLimit = la;
         LookaheadWalk.sizeLimitedMatches = new List<MatchInfo>();
         m = new MatchInfo();
         m.firstFreeLoc = 0;
         v = new List<MatchInfo>();
         v.Add(m);
         LookaheadWalk.considerSemanticLA = !Options.getForceLaCheck();
         LookaheadWalk.genFirstSet(v, nested);
         first = LookaheadWalk.sizeLimitedMatches;
         LookaheadWalk.sizeLimitedMatches = new List<MatchInfo>();
         LookaheadWalk.considerSemanticLA = false;
         LookaheadWalk.genFollowSet(v, exp, Expansion.NextGenerationIndex++);
         follow = LookaheadWalk.sizeLimitedMatches;
         if (la == 1) {
             if (CodeCheck(first)) {
                 CSharpCCErrors.Warning(nested,
                     "CSHARPCODE non-terminal within " + image(exp) +
                     " construct will force this construct to be entered in favor of " +
                     "expansions occurring after construct.");
             }
         }
         if ((m = overlap(first, follow)) == null) {
             break;
         }
         m1 = m;
     }
     if (la > Options.getOtherAmbiguityCheck()) {
         CSharpCCErrors.Warning("Choice conflict in " + image(exp) + " construct " +
                                "at line " + exp.Line + ", column " + exp.Column + ".");
         Console.Error.WriteLine("         Expansion nested within construct and expansion following construct");
         Console.Error.WriteLine("         have common prefixes, one of which is: " + image(m1));
         Console.Error.WriteLine("         Consider using a lookahead of " + la + " or more for nested expansion.");
     } else if (la > 1) {
         CSharpCCErrors.Warning("Choice conflict in " + image(exp) + " construct " +
                                "at line " + exp.Line + ", column " + exp.Column + ".");
         Console.Error.WriteLine("         Expansion nested within construct and expansion following construct");
         Console.Error.WriteLine("         have common prefixes, one of which is: " + image(m1));
         Console.Error.WriteLine("         Consider using a lookahead of " + la + " for nested expansion.");
     }
 }
예제 #5
0
        public static void choiceCalc(Choice choice)
        {
            int first = firstChoice(choice);

            // dbl[i] and dbr[i] are lists of size limited matches for choice i
            // of choice.  dbl ignores matches with semantic lookaheads (when force_la_check
            // is false), while dbr ignores semantic lookahead.
            IList <MatchInfo>[] dbl       = new IList <MatchInfo> [choice.Choices.Count];
            IList <MatchInfo>[] dbr       = new IList <MatchInfo> [choice.Choices.Count];
            int[]             minLA       = new int[choice.Choices.Count - 1];
            MatchInfo[]       overlapInfo = new MatchInfo[choice.Choices.Count - 1];
            int[]             other       = new int[choice.Choices.Count - 1];
            MatchInfo         m;
            IList <MatchInfo> v;
            bool overlapDetected;

            for (int la = 1; la <= Options.getChoiceAmbiguityCheck(); la++)
            {
                MatchInfo.laLimit = la;
                LookaheadWalk.considerSemanticLA = !Options.getForceLaCheck();
                for (int i = first; i < choice.Choices.Count - 1; i++)
                {
                    LookaheadWalk.sizeLimitedMatches = new List <MatchInfo>();
                    m = new MatchInfo();
                    m.firstFreeLoc = 0;
                    v = new List <MatchInfo>();
                    v.Add(m);
                    LookaheadWalk.genFirstSet(v, (Expansion)choice.Choices[i]);
                    dbl[i] = LookaheadWalk.sizeLimitedMatches;
                }
                LookaheadWalk.considerSemanticLA = false;
                for (int i = first + 1; i < choice.Choices.Count; i++)
                {
                    LookaheadWalk.sizeLimitedMatches = new List <MatchInfo>();
                    m = new MatchInfo();
                    m.firstFreeLoc = 0;
                    v = new List <MatchInfo>();
                    v.Add(m);
                    LookaheadWalk.genFirstSet(v, (Expansion)choice.Choices[i]);
                    dbr[i] = LookaheadWalk.sizeLimitedMatches;
                }
                if (la == 1)
                {
                    for (int i = first; i < choice.Choices.Count - 1; i++)
                    {
                        Expansion exp = (Expansion)choice.Choices[i];
                        if (Semanticize.EmptyExpansionExists(exp))
                        {
                            CSharpCCErrors.Warning(exp,
                                                   "This choice can expand to the empty token sequence " +
                                                   "and will therefore always be taken in favor of the choices appearing later.");
                            break;
                        }
                        else if (CodeCheck(dbl[i]))
                        {
                            CSharpCCErrors.Warning(exp,
                                                   "CSHARPCODE non-terminal will force this choice to be taken " +
                                                   "in favor of the choices appearing later.");
                            break;
                        }
                    }
                }
                overlapDetected = false;
                for (int i = first; i < choice.Choices.Count - 1; i++)
                {
                    for (int j = i + 1; j < choice.Choices.Count; j++)
                    {
                        if ((m = overlap(dbl[i], dbr[j])) != null)
                        {
                            minLA[i]        = la + 1;
                            overlapInfo[i]  = m;
                            other[i]        = j;
                            overlapDetected = true;
                            break;
                        }
                    }
                }
                if (!overlapDetected)
                {
                    break;
                }
            }
            for (int i = first; i < choice.Choices.Count - 1; i++)
            {
                if (explicitLA((Expansion)choice.Choices[i]) && !Options.getForceLaCheck())
                {
                    continue;
                }
                if (minLA[i] > Options.getChoiceAmbiguityCheck())
                {
                    CSharpCCErrors.Warning("Choice conflict involving two expansions at");
                    Console.Error.Write("         line " + ((Expansion)choice.Choices[i]).Line);
                    Console.Error.Write(", column " + ((Expansion)choice.Choices[i]).Column);
                    Console.Error.Write(" and line " + ((Expansion)choice.Choices[other[i]]).Line);
                    Console.Error.Write(", column " + ((Expansion)choice.Choices[other[i]]).Column);
                    Console.Error.WriteLine(" respectively.");
                    Console.Error.WriteLine("         A common prefix is: " + image(overlapInfo[i]));
                    Console.Error.WriteLine("         Consider using a lookahead of " + minLA[i] + " or more for earlier expansion.");
                }
                else if (minLA[i] > 1)
                {
                    CSharpCCErrors.Warning("Choice conflict involving two expansions at");
                    Console.Error.Write("         line " + ((Expansion)choice.Choices[i]).Line);
                    Console.Error.Write(", column " + ((Expansion)choice.Choices[i]).Column);
                    Console.Error.Write(" and line " + ((Expansion)choice.Choices[other[i]]).Line);
                    Console.Error.Write(", column " + ((Expansion)choice.Choices[other[i]]).Column);
                    Console.Error.WriteLine(" respectively.");
                    Console.Error.WriteLine("         A common prefix is: " + image(overlapInfo[i]));
                    Console.Error.WriteLine("         Consider using a lookahead of " + minLA[i] + " for earlier expansion.");
                }
            }
        }
예제 #6
0
        public static IList<MatchInfo> genFirstSet(IList<MatchInfo> partialMatches, Expansion exp)
        {
            if (exp is RegularExpression) {
                IList<MatchInfo> retval = new List<MatchInfo>();
                for (int i = 0; i < partialMatches.Count; i++) {
                    MatchInfo m = (MatchInfo) partialMatches[i];
                    MatchInfo mnew = new MatchInfo();
                    for (int j = 0; j < m.firstFreeLoc; j++) {
                        mnew.match[j] = m.match[j];
                    }
                    mnew.firstFreeLoc = m.firstFreeLoc;
                    mnew.match[mnew.firstFreeLoc++] = ((RegularExpression) exp).Ordinal;
                    if (mnew.firstFreeLoc == MatchInfo.laLimit) {
                        sizeLimitedMatches.Add(mnew);
                    } else {
                        retval.Add(mnew);
                    }
                }
                return retval;
            } else if (exp is NonTerminal) {
                NormalProduction prod = ((NonTerminal) exp).Production;
                if (prod is CodeProduction) {
                    return new List<MatchInfo>();
                } else {
                    return genFirstSet(partialMatches, prod.Expansion);
                }
            } else if (exp is Choice) {
                IList<MatchInfo> retval = new List<MatchInfo>();
                Choice ch = (Choice) exp;
                foreach (Expansion e in ch.Choices) {
                    IList<MatchInfo> v = genFirstSet(partialMatches, e);
                    listAppend(retval, v);
                }
                return retval;
            } else if (exp is Sequence) {
                IList<MatchInfo> v = partialMatches;
                Sequence seq = (Sequence) exp;
                foreach (Expansion unit in seq.Units) {
                    v = genFirstSet(v, unit);
                    if (v.Count == 0)
                        break;
                }
                return v;
            } else if (exp is OneOrMore) {
                IList<MatchInfo> retval = new List<MatchInfo>();
                IList<MatchInfo> v = partialMatches;
                OneOrMore om = (OneOrMore) exp;
                while (true) {
                    v = genFirstSet(v, om.Expansion);
                    if (v.Count == 0)
                        break;

                    listAppend(retval, v);
                }
                return retval;
            } else if (exp is ZeroOrMore) {
                IList<MatchInfo> retval = new List<MatchInfo>();
                listAppend(retval, partialMatches);
                IList<MatchInfo> v = partialMatches;
                ZeroOrMore zm = (ZeroOrMore) exp;
                while (true) {
                    v = genFirstSet(v, zm.Expansion);
                    if (v.Count == 0)
                        break;

                    listAppend(retval, v);
                }
                return retval;
            } else if (exp is ZeroOrOne) {
                IList<MatchInfo> retval = new List<MatchInfo>();
                listAppend(retval, partialMatches);
                listAppend(retval, genFirstSet(partialMatches, ((ZeroOrOne) exp).Expansion));
                return retval;
            } else if (exp is TryBlock) {
                return genFirstSet(partialMatches, ((TryBlock) exp).Expansion);
            } else if (considerSemanticLA &&
                       exp is Lookahead &&
                       ((Lookahead) exp).ActionTokens.Count != 0
                ) {
                return new List<MatchInfo>();
            } else {
                IList<MatchInfo> retval = new List<MatchInfo>();
                listAppend(retval, partialMatches);
                return retval;
            }
        }