Inheritance: GrammarTreeVisitor
Example #1
0
        public virtual void Process()
        {
            if (g.ast == null)
                return;

            // COLLECT RULE OBJECTS
            RuleCollector ruleCollector = new RuleCollector(g);
            ruleCollector.Process(g.ast);

            // CLONE RULE ASTs FOR CONTEXT REFERENCE
            foreach (Rule rule in ruleCollector.rules.Values)
            {
                IList<RuleAST> list;
                if (!g.contextASTs.TryGetValue(rule.GetBaseContext(), out list) || list == null)
                {
                    list = new List<RuleAST>();
                    g.contextASTs[rule.GetBaseContext()] = list;
                }

                list.Add((RuleAST)rule.ast.DupTree());
            }

            // DO BASIC / EASY SEMANTIC CHECKS
            int prevErrors = g.tool.errMgr.GetNumErrors();
            BasicSemanticChecks basics = new BasicSemanticChecks(g, ruleCollector);
            basics.Process();
            if (g.tool.errMgr.GetNumErrors() > prevErrors)
                return;

            // TRANSFORM LEFT-RECURSIVE RULES
            prevErrors = g.tool.errMgr.GetNumErrors();
            LeftRecursiveRuleTransformer lrtrans =
                new LeftRecursiveRuleTransformer(g.ast, ruleCollector.rules.Values, g);
            lrtrans.TranslateLeftRecursiveRules();

            // don't continue if we got errors during left-recursion elimination
            if (g.tool.errMgr.GetNumErrors() > prevErrors)
            {
                return;
            }

            // AUTO LEFT FACTORING
            LeftFactoringRuleTransformer lftrans = new LeftFactoringRuleTransformer(g.ast, ruleCollector.rules, g);
            lftrans.TranslateLeftFactoredRules();

            // STORE RULES IN GRAMMAR
            foreach (Rule r in ruleCollector.rules.Values)
            {
                g.DefineRule(r);
            }

            // COLLECT SYMBOLS: RULES, ACTIONS, TERMINALS, ...
            SymbolCollector collector = new SymbolCollector(g);
            collector.Process(g.ast);

            // CHECK FOR SYMBOL COLLISIONS
            SymbolChecks symcheck = new SymbolChecks(g, collector);
            symcheck.Process(); // side-effect: strip away redef'd rules.

            foreach (GrammarAST a in collector.namedActions)
            {
                g.DefineAction(a);
            }

            // LINK (outermost) ALT NODES WITH Alternatives
            foreach (Rule r in g.rules.Values)
            {
                for (int i = 1; i <= r.numberOfAlts; i++)
                {
                    r.alt[i].ast.alt = r.alt[i];
                }
            }

            // ASSIGN TOKEN TYPES
            g.ImportTokensFromTokensFile();
            if (g.IsLexer())
            {
                AssignLexerTokenTypes(g, collector.tokensDefs);
            }
            else
            {
                AssignTokenTypes(g, collector.tokensDefs,
                                 collector.tokenIDRefs, collector.terminals);
            }

            symcheck.CheckForModeConflicts(g);

            AssignChannelTypes(g, collector.channelDefs);

            // CHECK RULE REFS NOW (that we've defined rules in grammar)
            symcheck.CheckRuleArgs(g, collector.rulerefs);
            IdentifyStartRules(collector);
            symcheck.CheckForQualifiedRuleIssues(g, collector.qualifiedRulerefs);

            // don't continue if we got symbol errors
            if (g.tool.GetNumErrors() > 0)
                return;

            // CHECK ATTRIBUTE EXPRESSIONS FOR SEMANTIC VALIDITY
            AttributeChecks.CheckAllAttributeExpressions(g);

            UseDefAnalyzer.TrackTokenRuleRefsInActions(g);
        }
Example #2
0
        public virtual void Process()
        {
            if (g.ast == null)
            {
                return;
            }

            // COLLECT RULE OBJECTS
            RuleCollector ruleCollector = new RuleCollector(g);

            ruleCollector.Process(g.ast);

            // CLONE RULE ASTs FOR CONTEXT REFERENCE
            foreach (Rule rule in ruleCollector.rules.Values)
            {
                IList <RuleAST> list;
                if (!g.contextASTs.TryGetValue(rule.GetBaseContext(), out list) || list == null)
                {
                    list = new List <RuleAST>();
                    g.contextASTs[rule.GetBaseContext()] = list;
                }

                list.Add((RuleAST)rule.ast.DupTree());
            }

            // DO BASIC / EASY SEMANTIC CHECKS
            int prevErrors             = g.tool.errMgr.GetNumErrors();
            BasicSemanticChecks basics = new BasicSemanticChecks(g, ruleCollector);

            basics.Process();
            if (g.tool.errMgr.GetNumErrors() > prevErrors)
            {
                return;
            }

            // TRANSFORM LEFT-RECURSIVE RULES
            prevErrors = g.tool.errMgr.GetNumErrors();
            LeftRecursiveRuleTransformer lrtrans =
                new LeftRecursiveRuleTransformer(g.ast, ruleCollector.rules.Values, g);

            lrtrans.TranslateLeftRecursiveRules();

            // don't continue if we got errors during left-recursion elimination
            if (g.tool.errMgr.GetNumErrors() > prevErrors)
            {
                return;
            }

            // AUTO LEFT FACTORING
            LeftFactoringRuleTransformer lftrans = new LeftFactoringRuleTransformer(g.ast, ruleCollector.rules, g);

            lftrans.TranslateLeftFactoredRules();

            // STORE RULES IN GRAMMAR
            foreach (Rule r in ruleCollector.rules.Values)
            {
                g.DefineRule(r);
            }

            // COLLECT SYMBOLS: RULES, ACTIONS, TERMINALS, ...
            SymbolCollector collector = new SymbolCollector(g);

            collector.Process(g.ast);

            // CHECK FOR SYMBOL COLLISIONS
            SymbolChecks symcheck = new SymbolChecks(g, collector);

            symcheck.Process(); // side-effect: strip away redef'd rules.

            foreach (GrammarAST a in collector.namedActions)
            {
                g.DefineAction(a);
            }

            // LINK (outermost) ALT NODES WITH Alternatives
            foreach (Rule r in g.rules.Values)
            {
                for (int i = 1; i <= r.numberOfAlts; i++)
                {
                    r.alt[i].ast.alt = r.alt[i];
                }
            }

            // ASSIGN TOKEN TYPES
            g.ImportTokensFromTokensFile();
            if (g.IsLexer())
            {
                AssignLexerTokenTypes(g, collector.tokensDefs);
            }
            else
            {
                AssignTokenTypes(g, collector.tokensDefs,
                                 collector.tokenIDRefs, collector.terminals);
            }

            symcheck.CheckForModeConflicts(g);

            AssignChannelTypes(g, collector.channelDefs);

            // CHECK RULE REFS NOW (that we've defined rules in grammar)
            symcheck.CheckRuleArgs(g, collector.rulerefs);
            IdentifyStartRules(collector);
            symcheck.CheckForQualifiedRuleIssues(g, collector.qualifiedRulerefs);

            // don't continue if we got symbol errors
            if (g.tool.GetNumErrors() > 0)
            {
                return;
            }

            // CHECK ATTRIBUTE EXPRESSIONS FOR SEMANTIC VALIDITY
            AttributeChecks.CheckAllAttributeExpressions(g);

            UseDefAnalyzer.TrackTokenRuleRefsInActions(g);
        }
        /** Return true if successful */
        public virtual bool TranslateLeftRecursiveRule(GrammarRootAST ast,
                                                  LeftRecursiveRule r,
                                                  string language)
        {
            //tool.log("grammar", ruleAST.toStringTree());
            GrammarAST prevRuleAST = r.ast;
            string ruleName = prevRuleAST.GetChild(0).Text;
            LeftRecursiveRuleAnalyzer leftRecursiveRuleWalker =
                new LeftRecursiveRuleAnalyzer(prevRuleAST, tool, ruleName, language);
            bool isLeftRec;
            try
            {
                //System.Console.WriteLine("TESTING ---------------\n" +
                //                   leftRecursiveRuleWalker.Text(ruleAST));
                isLeftRec = leftRecursiveRuleWalker.rec_rule();
            }
            catch (RecognitionException)
            {
                isLeftRec = false; // didn't match; oh well
            }
            if (!isLeftRec)
                return false;

            // replace old rule's AST; first create text of altered rule
            GrammarAST RULES = (GrammarAST)ast.GetFirstChildWithType(ANTLRParser.RULES);
            string newRuleText = leftRecursiveRuleWalker.GetArtificialOpPrecRule();
            //System.Console.WriteLine("created: " + newRuleText);
            // now parse within the context of the grammar that originally created
            // the AST we are transforming. This could be an imported grammar so
            // we cannot just reference this.g because the role might come from
            // the imported grammar and not the root grammar (this.g)
            RuleAST t = ParseArtificialRule(prevRuleAST.g, newRuleText);

            // reuse the name token from the original AST since it refers to the proper source location in the original grammar
            ((GrammarAST)t.GetChild(0)).Token = ((GrammarAST)prevRuleAST.GetChild(0)).Token;

            // update grammar AST and set rule's AST.
            RULES.SetChild(prevRuleAST.ChildIndex, t);
            r.ast = t;

            // Reduce sets in newly created rule tree
            GrammarTransformPipeline transform = new GrammarTransformPipeline(g, g.tool);
            transform.ReduceBlocksToSets(r.ast);
            transform.ExpandParameterizedLoops(r.ast);

            // Rerun semantic checks on the new rule
            RuleCollector ruleCollector = new RuleCollector(g);
            ruleCollector.Visit(t, "rule");
            BasicSemanticChecks basics = new BasicSemanticChecks(g, ruleCollector);
            // disable the assoc element option checks because they are already
            // handled for the pre-transformed rule.
            basics.checkAssocElementOption = false;
            basics.Visit(t, "rule");

            // track recursive alt info for codegen
            r.recPrimaryAlts = new List<LeftRecursiveRuleAltInfo>();
            foreach (var altInfo in leftRecursiveRuleWalker.prefixAndOtherAlts)
                r.recPrimaryAlts.Add(altInfo);
            if (r.recPrimaryAlts.Count == 0)
            {
                tool.errMgr.GrammarError(ErrorType.NO_NON_LR_ALTS, g.fileName, ((GrammarAST)r.ast.GetChild(0)).Token, r.name);
            }

            r.recOpAlts = new OrderedHashMap<int, LeftRecursiveRuleAltInfo>();
            foreach (var pair in leftRecursiveRuleWalker.binaryAlts)
                r.recOpAlts[pair.Key] = pair.Value;
            foreach (var pair in leftRecursiveRuleWalker.ternaryAlts)
                r.recOpAlts[pair.Key] = pair.Value;
            foreach (var pair in leftRecursiveRuleWalker.suffixAlts)
                r.recOpAlts[pair.Key] = pair.Value;

            // walk alt info records and set their altAST to point to appropriate ALT subtree
            // from freshly created AST
            SetAltASTPointers(r, t);

            // update Rule to just one alt and add prec alt
            ActionAST arg = (ActionAST)r.ast.GetFirstChildWithType(ANTLRParser.ARG_ACTION);
            if (arg != null)
            {
                r.args = ScopeParser.ParseTypedArgList(arg, arg.Text, g);
                r.args.type = AttributeDict.DictType.ARG;
                r.args.ast = arg;
                arg.resolver = r.alt[1]; // todo: isn't this Rule or something?
            }

            // define labels on recursive rule refs we delete; they don't point to nodes of course
            // these are so $label in action translation works
            foreach (System.Tuple<GrammarAST, string> pair in leftRecursiveRuleWalker.leftRecursiveRuleRefLabels)
            {
                GrammarAST labelNode = pair.Item1;
                GrammarAST labelOpNode = (GrammarAST)labelNode.Parent;
                GrammarAST elementNode = (GrammarAST)labelOpNode.GetChild(1);
                LabelElementPair lp = new LabelElementPair(g, labelNode, elementNode, labelOpNode.Type);
                r.alt[1].labelDefs.Map(labelNode.Text, lp);
            }
            // copy to rule from walker
            r.leftRecursiveRuleRefLabels = leftRecursiveRuleWalker.leftRecursiveRuleRefLabels;

            tool.Log("grammar", "added: " + t.ToStringTree());
            return true;
        }