have pieces of DFA conversion working
[git-p4: depot-paths = "//depot/code/antlr4/main/": change = 6742]
This commit is contained in:
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665b64fee0
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@ -1 +1,3 @@
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action-edge() ::= <<
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<src> -> <target> [fontsize=11, fontname="Courier", arrowsize=.7, label = "<label>"<if(arrowhead)>, arrowhead = <arrowhead><endif>];
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>>
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@ -1 +1,4 @@
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decision-rank() ::= <<
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{rank=same; rankdir=TB; <states; separator="; ">}
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>>
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@ -1,7 +1,8 @@
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dfa() ::= <<
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digraph NFA {
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<if(rankdir)>rankdir=<rankdir>;<endif>
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<decisionRanks; separator="\n">
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<states; separator="\n">
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<edges; separator="\n">
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}
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>>
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@ -1 +1,4 @@
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edge(src,target,label,arrowhead) ::= <<
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<src> -> <target> [fontsize=11, fontname="Courier", arrowsize=.7, label = "<label>"<if(arrowhead)>, arrowhead = <arrowhead><endif>];
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>>
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@ -1 +1,3 @@
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epsilon-edge(src,label,target,arrowhead) ::= <<
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<src> -> <target> [fontname="Times-Italic", label = "e"];
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>>
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@ -1,6 +1,8 @@
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nfa(startState, states, edges, rankdir, decisionRanks) ::= <<
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digraph NFA {
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rankdir=LR;
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<decisionRanks; separator="\n">
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<states; separator="\n">
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<edges; separator="\n">
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}
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>>
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@ -1 +1,3 @@
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state(state, useBox, name) ::= <<
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node [fontsize=11, shape = <if(useBox)>box<else>circle, fixedsize=true, width=.4<endif>]; <name>
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>>
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@ -1 +1,3 @@
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stopstate(name,useBox) ::= <<
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node [fontsize=11, shape = <if(useBox)>polygon,sides=4,peripheries=2<else>doublecircle, fixedsize=true, width=.6<endif>]; <name>
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>>
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@ -1,5 +1,6 @@
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package org.antlr.v4;
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import org.antlr.codegen.CodeGenerator;
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import org.antlr.runtime.*;
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import org.antlr.runtime.tree.TreeWizard;
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import org.antlr.v4.analysis.AnalysisPipeline;
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@ -12,8 +13,7 @@ import org.antlr.v4.parse.GrammarASTAdaptor;
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import org.antlr.v4.semantics.SemanticPipeline;
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import org.antlr.v4.tool.*;
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import java.io.File;
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import java.io.IOException;
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import java.io.*;
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import java.util.*;
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public class Tool {
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@ -371,6 +371,9 @@ public class Tool {
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NFAFactory factory = new ParserNFAFactory(g);
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if ( g.getType()==ANTLRParser.LEXER ) factory = new LexerNFAFactory(g);
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g.nfa = factory.createNFA();
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if ( generate_NFA_dot ) generateNFAs(g);
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// PERFORM GRAMMAR ANALYSIS ON NFA: BUILD DECISION DFAs
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AnalysisPipeline anal = new AnalysisPipeline(g);
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@ -480,6 +483,151 @@ public class Tool {
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return lexerAST;
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}
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protected void generateNFAs(Grammar g) {
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DOTGenerator dotGenerator = new DOTGenerator(g);
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List<Grammar> grammars = new ArrayList<Grammar>();
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grammars.add(g);
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List<Grammar> imported = g.getAllImportedGrammars();
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if ( imported!=null ) grammars.addAll(imported);
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for (Grammar ig : grammars) {
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for (Rule r : ig.rules.values()) {
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try {
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String dot = dotGenerator.getDOT(g.nfa.ruleToStartState.get(r));
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if (dot != null) {
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writeDOTFile(g, r, dot);
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}
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} catch (IOException ioe) {
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ErrorManager.toolError(ErrorType.CANNOT_WRITE_FILE, ioe);
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}
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}
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}
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}
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protected void writeDOTFile(Grammar g, Rule r, String dot) throws IOException {
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writeDOTFile(g, r.g.name + "." + r.name, dot);
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}
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protected void writeDOTFile(Grammar g, String name, String dot) throws IOException {
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Writer fw = getOutputFile(g, name + ".dot");
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fw.write(dot);
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fw.close();
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}
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/** This method is used by all code generators to create new output
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* files. If the outputDir set by -o is not present it will be created.
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* The final filename is sensitive to the output directory and
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* the directory where the grammar file was found. If -o is /tmp
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* and the original grammar file was foo/t.g then output files
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* go in /tmp/foo.
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*
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* The output dir -o spec takes precedence if it's absolute.
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* E.g., if the grammar file dir is absolute the output dir is given
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* precendence. "-o /tmp /usr/lib/t.g" results in "/tmp/T.java" as
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* output (assuming t.g holds T.java).
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*
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* If no -o is specified, then just write to the directory where the
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* grammar file was found.
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*
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* If outputDirectory==null then write a String.
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*/
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public Writer getOutputFile(Grammar g, String fileName) throws IOException {
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if (outputDirectory == null) {
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return new StringWriter();
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}
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// output directory is a function of where the grammar file lives
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// for subdir/T.g, you get subdir here. Well, depends on -o etc...
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// But, if this is a .tokens file, then we force the output to
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// be the base output directory (or current directory if there is not a -o)
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//
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File outputDir;
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if (fileName.endsWith(CodeGenerator.VOCAB_FILE_EXTENSION)) {
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if (haveOutputDir) {
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outputDir = new File(outputDirectory);
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}
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else {
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outputDir = new File(".");
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}
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}
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else {
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outputDir = getOutputDirectory(g.fileName);
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}
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File outputFile = new File(outputDir, fileName);
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if (!outputDir.exists()) {
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outputDir.mkdirs();
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}
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FileWriter fw = new FileWriter(outputFile);
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return new BufferedWriter(fw);
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}
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/**
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* Return the location where ANTLR will generate output files for a given file. This is a
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* base directory and output files will be relative to here in some cases
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* such as when -o option is used and input files are given relative
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* to the input directory.
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*
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* @param fileNameWithPath path to input source
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* @return
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*/
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public File getOutputDirectory(String fileNameWithPath) {
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File outputDir = new File(outputDirectory);
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String fileDirectory;
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// Some files are given to us without a PATH but should should
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// still be written to the output directory in the relative path of
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// the output directory. The file directory is either the set of sub directories
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// or just or the relative path recorded for the parent grammar. This means
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// that when we write the tokens files, or the .java files for imported grammars
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// taht we will write them in the correct place.
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//
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if (fileNameWithPath.lastIndexOf(File.separatorChar) == -1) {
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// No path is included in the file name, so make the file
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// directory the same as the parent grammar (which might sitll be just ""
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// but when it is not, we will write the file in the correct place.
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//
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fileDirectory = grammarOutputDirectory;
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}
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else {
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fileDirectory = fileNameWithPath.substring(0, fileNameWithPath.lastIndexOf(File.separatorChar));
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}
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if ( fileDirectory == null ) {
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fileDirectory = ".";
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}
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if (haveOutputDir) {
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// -o /tmp /var/lib/t.g => /tmp/T.java
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// -o subdir/output /usr/lib/t.g => subdir/output/T.java
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// -o . /usr/lib/t.g => ./T.java
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if ((fileDirectory != null && !forceRelativeOutput) &&
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(new File(fileDirectory).isAbsolute() ||
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fileDirectory.startsWith("~")) || // isAbsolute doesn't count this :(
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forceAllFilesToOutputDir) {
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// somebody set the dir, it takes precendence; write new file there
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outputDir = new File(outputDirectory);
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}
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else {
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// -o /tmp subdir/t.g => /tmp/subdir/t.g
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if (fileDirectory != null) {
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outputDir = new File(outputDirectory, fileDirectory);
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}
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else {
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outputDir = new File(outputDirectory);
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}
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}
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}
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else {
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// they didn't specify a -o dir so just write to location
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// where grammar is, absolute or relative, this will only happen
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// with command line invocation as build tools will always
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// supply an output directory.
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//
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outputDir = new File(fileDirectory);
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}
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return outputDir;
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}
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private static void version() {
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ErrorManager.info("ANTLR Parser Generator Version " + new Tool().VERSION);
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}
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@ -3,7 +3,7 @@ package org.antlr.v4.automata;
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import org.antlr.v4.misc.IntervalSet;
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import org.antlr.v4.tool.Grammar;
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/** */
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/** TODO: make all transitions sets? */
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public class AtomTransition extends Transition {
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/** The token type or character value; or, signifies special label. */
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protected int label;
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@ -13,6 +13,8 @@ public class AtomTransition extends Transition {
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this.target = target;
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}
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public IntervalSet label() { return IntervalSet.of(label); }
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public int hashCode() { return label; }
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public boolean equals(Object o) {
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@ -37,7 +37,7 @@ public class DFASerializer {
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marked.add(s);
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for (int i=0; i<n; i++) {
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Edge t = s.transition(i);
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buf.append("-"+t.toString()+"->"+ getStateString(t.target)+'\n');
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buf.append("-"+t.toString(g)+"->"+ getStateString(t.target)+'\n');
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}
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}
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return buf.toString();
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@ -1,5 +1,6 @@
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package org.antlr.v4.automata;
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import org.antlr.analysis.NFA;
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import org.antlr.v4.misc.Utils;
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import org.stringtemplate.v4.misc.MultiMap;
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@ -195,7 +196,7 @@ public class DFAState {
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if ( cachedUniquelyPredicatedAlt!=NFA.INVALID_ALT_NUMBER ) {
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return cachedUniquelyPredicatedAlt;
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}
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int alt = org.antlr.analysis.NFA.INVALID_ALT_NUMBER;
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int alt = NFA.INVALID_ALT_NUMBER;
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for (NFAConfig c : nfaConfigs) {
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if ( alt== NFA.INVALID_ALT_NUMBER ) {
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alt = c.alt; // found first nonresolved alt
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@ -208,6 +209,23 @@ public class DFAState {
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return alt;
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}
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/** Return the uniquely mentioned alt from the NFA configurations;
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* Ignore the resolved bit etc... Return INVALID_ALT_NUMBER
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* if there is more than one alt mentioned.
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*/
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public int getUniqueAlt() {
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int alt = NFA.INVALID_ALT_NUMBER;
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for (NFAConfig c : nfaConfigs) {
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if ( alt== NFA.INVALID_ALT_NUMBER ) {
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alt = c.alt; // found first alt
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}
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else if ( c.alt!=alt ) {
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return NFA.INVALID_ALT_NUMBER;
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}
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}
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return alt;
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}
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/** Get the set of all alts mentioned by all NFA configurations in this
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* DFA state.
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*/
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@ -220,7 +238,13 @@ public class DFAState {
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return alts;
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}
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public Set<NFAState> getUniqueNFAStates() {
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Set<NFAState> alts = new HashSet<NFAState>();
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for (NFAConfig c : nfaConfigs) alts.add(c.state);
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if ( alts.size()==0 ) return null;
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return alts;
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}
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public int getNumberOfTransitions() { return edges.size(); }
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public void addTransition(Edge e) { edges.add(e); }
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@ -5,15 +5,17 @@ import org.antlr.v4.tool.Grammar;
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/** A DFA edge (NFA edges are called transitions) */
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public class Edge {
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public int atom = Label.INVALID;
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public IntervalSet set;
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public IntervalSet label;
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public DFAState target;
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public Edge(DFAState target) { this.target = target; }
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public Edge(DFAState target, IntervalSet label) {
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this.target = target;
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this.label = label;
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}
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public String toString() { return label.toString(); }
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public String toString(Grammar g) {
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if ( set==null ) return g.getTokenDisplayName(atom);
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else return set.toString(g);
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return label.toString(g);
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}
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}
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@ -1,6 +1,7 @@
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package org.antlr.v4.automata;
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import org.antlr.runtime.Token;
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import org.antlr.v4.misc.IntervalSet;
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/** A state machine transition label. A label can be either a simple
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* label such as a token or character. A label can be a set of char or
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@ -73,6 +74,10 @@ public abstract class Label implements /*Comparable, */ Cloneable {
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*/
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public static final int EOR_TOKEN_TYPE = Token.EOR_TOKEN_TYPE;
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public int atom = Label.INVALID;
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public IntervalSet set;
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public int compareTo(Object o) {
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return 0; // TODO: impl
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}
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@ -1,10 +1,9 @@
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package org.antlr.v4.automata;
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import org.antlr.v4.misc.IntervalSet;
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import org.antlr.v4.tool.Grammar;
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import java.util.ArrayList;
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import java.util.LinkedList;
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import java.util.List;
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import java.util.*;
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/** Code that embodies the NFA conversion to DFA. A new object is needed
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* per DFA (also required for thread safety if multiple conversions
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@ -21,6 +20,12 @@ public class NFAToDFAConverter {
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/** A list of DFA states we still need to process during NFA conversion */
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List<DFAState> work = new LinkedList<DFAState>();
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/** Used to prevent the closure operation from looping to itself and
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* hence looping forever. Sensitive to the NFA state, the alt, and
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* the stack context.
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*/
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Set<NFAConfig> closureBusy;
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public static boolean debug = false;
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public NFAToDFAConverter(Grammar g, DecisionState nfaStartState) {
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@ -36,12 +41,94 @@ public class NFAToDFAConverter {
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// while more DFA states to check, process them
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while ( work.size()>0 ) {
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DFAState d = work.get(0);
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reach(d);
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work.remove(0); // we're done with this DFA state
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}
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return dfa;
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}
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/** From this node, add a d--a-->t transition for all
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* labels 'a' where t is a DFA node created
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* from the set of NFA states reachable from any NFA
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* state in DFA state d.
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*/
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void reach(DFAState d) {
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OrderedHashSet<IntervalSet> labels = getReachableLabels(d);
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for (IntervalSet label : labels) {
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DFAState newd = reach(d, label);
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if ( debug ) {
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System.out.println("DFA state after reach "+label+" "+d+"-" +
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label.toString(g)+"->"+newd);
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}
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if ( newd==null ) {
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// nothing was reached by label due to conflict resolution
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// EOT also seems to be in here occasionally probably due
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// to an end-of-rule state seeing it even though we'll pop
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// an invoking state off the state; don't bother to conflict
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// as this labels set is a covering approximation only.
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continue;
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}
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if ( newd.getUniqueAlt()== NFA.INVALID_ALT_NUMBER ) {
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// Only compute closure if a unique alt number is not known.
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// If a unique alternative is mentioned among all NFA
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// configurations then there is no possibility of needing to look
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// beyond this state; also no possibility of a nondeterminism.
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// This optimization May 22, 2006 just dropped -Xint time
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// for analysis of Java grammar from 11.5s to 2s! Wow.
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closure(newd); // add any NFA states reachable via epsilon
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}
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// add if not in DFA yet and then make d-label->t
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DFAState targetState = newd;
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DFAState existingState = dfa.addState(newd);
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if ( newd != existingState ) {
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// already there...use/return the existing DFA state.
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targetState = existingState;
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}
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d.addTransition(new Edge(targetState, label));
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//
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// numberOfEdgesEmanating +=
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// addTransition(d, label, targetState, targetToLabelMap);
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}
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}
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/** Given the set of NFA states in DFA state d, find all NFA states
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* reachable traversing label arcs. By definition, there can be
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* only one DFA state reachable by a single label from DFA state d so we must
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* find and merge all NFA states reachable via label. Return a new
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* DFAState that has all of those NFA states with their context.
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*
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* Because we cannot jump to another rule nor fall off the end of a rule
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* via a non-epsilon transition, NFA states reachable from d have the
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* same configuration as the NFA state in d. So if NFA state 7 in d's
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* configurations can reach NFA state 13 then 13 will be added to the
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* new DFAState (labelDFATarget) with the same configuration as state
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* 7 had.
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*/
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public DFAState reach(DFAState d, IntervalSet label) {
|
||||
//System.out.println("reach "+label.toString(dfa.nfa.grammar)+" from "+d.stateNumber);
|
||||
DFAState labelTarget = dfa.newState();
|
||||
|
||||
for (NFAConfig c : d.nfaConfigs) {
|
||||
int n = c.state.getNumberOfTransitions();
|
||||
for (int i=0; i<n; i++) { // for each transition
|
||||
Transition t = c.state.transition(i);
|
||||
// found a transition with label; does it collide with label?
|
||||
if ( !t.isEpsilon() && !t.label().and(label).isNil() ) {
|
||||
// add NFA target to (potentially) new DFA state
|
||||
labelTarget.addNFAConfig(t.target, c.alt, c.context);
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
return labelTarget;
|
||||
}
|
||||
|
||||
/** From this first NFA state of a decision, create a DFA.
|
||||
* Walk each alt in decision and compute closure from the start of that
|
||||
* rule, making sure that the closure does not include other alts within
|
||||
|
@ -57,10 +144,12 @@ public class NFAToDFAConverter {
|
|||
for (int altNum=1; altNum<=dfa.nAlts; altNum++) {
|
||||
Transition t = nfaStartState.transition(altNum-1);
|
||||
NFAState altStart = t.target;
|
||||
d.addNFAConfig(altStart, altNum+1, null);
|
||||
d.addNFAConfig(altStart, altNum, null);
|
||||
|
||||
}
|
||||
|
||||
System.out.println("before closure start d="+d);
|
||||
|
||||
closure(d);
|
||||
|
||||
return d;
|
||||
|
@ -75,12 +164,16 @@ public class NFAToDFAConverter {
|
|||
System.out.println("closure("+d+")");
|
||||
}
|
||||
|
||||
closureBusy = new HashSet<NFAConfig>();
|
||||
|
||||
List<NFAConfig> configs = new ArrayList<NFAConfig>();
|
||||
for (NFAConfig c : d.nfaConfigs) {
|
||||
closure(c.state, c.alt, c.context, configs);
|
||||
}
|
||||
d.nfaConfigs.addAll(configs); // Add new NFA configs to DFA state d
|
||||
|
||||
closureBusy = null; // wack all that memory used during closure
|
||||
|
||||
System.out.println("after closure d="+d);
|
||||
}
|
||||
|
||||
|
@ -92,15 +185,159 @@ public class NFAToDFAConverter {
|
|||
NFAConfig proposedNFAConfig =
|
||||
new NFAConfig(s, altNum, context);
|
||||
|
||||
if ( closureBusy.contains(proposedNFAConfig) ) {
|
||||
return;
|
||||
}
|
||||
|
||||
closureBusy.add(proposedNFAConfig);
|
||||
|
||||
// p itself is always in closure
|
||||
configs.add(proposedNFAConfig);
|
||||
|
||||
if ( s instanceof RuleStopState ) {
|
||||
// do follow
|
||||
int n = s.getNumberOfTransitions();
|
||||
for (int i=0; i<n; i++) {
|
||||
Transition t = s.transition(i);
|
||||
}
|
||||
return;
|
||||
}
|
||||
|
||||
int n = s.getNumberOfTransitions();
|
||||
for (int i=0; i<n; i++) {
|
||||
Transition t = s.transition(i);
|
||||
if ( t.isEpsilon() ) {
|
||||
if ( t instanceof RuleTransition ) {
|
||||
NFAState newContext = context;
|
||||
if ( context==null ) newContext = s; // push new context
|
||||
closure(t.target, altNum, newContext, configs);
|
||||
}
|
||||
else if ( t.isEpsilon() ) {
|
||||
closure(t.target, altNum, context, configs);
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
public OrderedHashSet<IntervalSet> getReachableLabels(DFAState d) {
|
||||
OrderedHashSet<IntervalSet> reachableLabels = new OrderedHashSet<IntervalSet>();
|
||||
for (NFAState s : d.getUniqueNFAStates()) { // for each state
|
||||
int n = s.getNumberOfTransitions();
|
||||
for (int i=0; i<n; i++) { // for each transition
|
||||
Transition t = s.transition(i);
|
||||
IntervalSet label = null;
|
||||
if ( t instanceof AtomTransition ) {
|
||||
label = IntervalSet.of(((AtomTransition)t).label);
|
||||
}
|
||||
else if ( t instanceof SetTransition ) {
|
||||
label = ((SetTransition)t).label;
|
||||
}
|
||||
if ( label!=null ) {
|
||||
addReachableLabel(reachableLabels, label);
|
||||
}
|
||||
}
|
||||
}
|
||||
System.out.println("reachable labels for "+d+"="+reachableLabels);
|
||||
return reachableLabels;
|
||||
}
|
||||
|
||||
/** Add label uniquely and disjointly; intersection with
|
||||
* another set or int/char forces breaking up the set(s).
|
||||
*
|
||||
* Example, if reachable list of labels is [a..z, {k,9}, 0..9],
|
||||
* the disjoint list will be [{a..j,l..z}, k, 9, 0..8].
|
||||
*
|
||||
* As we add NFA configurations to a DFA state, we might as well track
|
||||
* the set of all possible transition labels to make the DFA conversion
|
||||
* more efficient. W/o the reachable labels, we'd need to check the
|
||||
* whole vocabulary space (could be 0..\uFFFE)! The problem is that
|
||||
* labels can be sets, which may overlap with int labels or other sets.
|
||||
* As we need a deterministic set of transitions from any
|
||||
* state in the DFA, we must make the reachable labels set disjoint.
|
||||
* This operation amounts to finding the character classes for this
|
||||
* DFA state whereas with tools like flex, that need to generate a
|
||||
* homogeneous DFA, must compute char classes across all states.
|
||||
* We are going to generate DFAs with heterogeneous states so we
|
||||
* only care that the set of transitions out of a single state is
|
||||
* unique. :)
|
||||
*
|
||||
* The idea for adding a new set, t, is to look for overlap with the
|
||||
* elements of existing list s. Upon overlap, replace
|
||||
* existing set s[i] with two new disjoint sets, s[i]-t and s[i]&t.
|
||||
* (if s[i]-t is nil, don't add). The remainder is t-s[i], which is
|
||||
* what you want to add to the set minus what was already there. The
|
||||
* remainder must then be compared against the i+1..n elements in s
|
||||
* looking for another collision. Each collision results in a smaller
|
||||
* and smaller remainder. Stop when you run out of s elements or
|
||||
* remainder goes to nil. If remainder is non nil when you run out of
|
||||
* s elements, then add remainder to the end.
|
||||
*/
|
||||
protected void addReachableLabel(OrderedHashSet<IntervalSet> reachableLabels,
|
||||
IntervalSet label)
|
||||
{
|
||||
/*
|
||||
System.out.println("addReachableLabel to state "+dfa.decisionNumber+"."+stateNumber+": "+label.getSet().toString(dfa.nfa.grammar));
|
||||
System.out.println("start of add to state "+dfa.decisionNumber+"."+stateNumber+": " +
|
||||
"reachableLabels="+reachableLabels.toString());
|
||||
*/
|
||||
if ( reachableLabels.contains(label) ) { // exact label present
|
||||
return;
|
||||
}
|
||||
IntervalSet remainder = label; // remainder starts out as whole set to add
|
||||
int n = reachableLabels.size(); // only look at initial elements
|
||||
// walk the existing list looking for the collision
|
||||
for (int i=0; i<n; i++) {
|
||||
IntervalSet rl = reachableLabels.get(i);
|
||||
/*
|
||||
System.out.println("comparing ["+i+"]: "+label.toString(dfa.nfa.grammar)+" & "+
|
||||
rl.toString(dfa.nfa.grammar)+"="+
|
||||
intersection.toString(dfa.nfa.grammar));
|
||||
*/
|
||||
IntervalSet intersection = (IntervalSet)label.and(rl);
|
||||
if ( intersection.isNil() ) {
|
||||
continue;
|
||||
}
|
||||
//System.out.println(label+" collides with "+rl);
|
||||
|
||||
// For any (s_i, t) with s_i&t!=nil replace with (s_i-t, s_i&t)
|
||||
// (ignoring s_i-t if nil; don't put in list)
|
||||
|
||||
// Replace existing s_i with intersection since we
|
||||
// know that will always be a non nil character class
|
||||
IntervalSet s_i = rl;
|
||||
reachableLabels.set(i, intersection);
|
||||
|
||||
// Compute s_i-t to see what is in current set and not in incoming
|
||||
IntervalSet existingMinusNewElements = (IntervalSet)s_i.subtract(label);
|
||||
//System.out.println(s_i+"-"+t+"="+existingMinusNewElements);
|
||||
if ( !existingMinusNewElements.isNil() ) {
|
||||
// found a new character class, add to the end (doesn't affect
|
||||
// outer loop duration due to n computation a priori.
|
||||
reachableLabels.add(existingMinusNewElements);
|
||||
}
|
||||
|
||||
/*
|
||||
System.out.println("after collision, " +
|
||||
"reachableLabels="+reachableLabels.toString());
|
||||
*/
|
||||
|
||||
// anything left to add to the reachableLabels?
|
||||
remainder = (IntervalSet)label.subtract(s_i);
|
||||
if ( remainder.isNil() ) {
|
||||
break; // nothing left to add to set. done!
|
||||
}
|
||||
|
||||
label = remainder;
|
||||
}
|
||||
if ( !remainder.isNil() ) {
|
||||
/*
|
||||
System.out.println("before add remainder to state "+dfa.decisionNumber+"."+stateNumber+": " +
|
||||
"reachableLabels="+reachableLabels.toString());
|
||||
System.out.println("remainder state "+dfa.decisionNumber+"."+stateNumber+": "+remainder.toString(dfa.nfa.grammar));
|
||||
*/
|
||||
reachableLabels.add(remainder);
|
||||
}
|
||||
/*
|
||||
System.out.println("#END of add to state "+dfa.decisionNumber+"."+stateNumber+": " +
|
||||
"reachableLabels="+reachableLabels.toString());
|
||||
*/
|
||||
}
|
||||
}
|
||||
|
|
|
@ -1,6 +1,7 @@
|
|||
package org.antlr.v4.automata;
|
||||
|
||||
import org.antlr.v4.codegen.Target;
|
||||
import org.antlr.v4.misc.IntervalSet;
|
||||
|
||||
public class RangeTransition extends Transition {
|
||||
public int from;
|
||||
|
@ -10,10 +11,14 @@ public class RangeTransition extends Transition {
|
|||
this.from = from;
|
||||
this.to = to;
|
||||
}
|
||||
|
||||
public int compareTo(Object o) {
|
||||
return 0;
|
||||
}
|
||||
|
||||
@Override
|
||||
public IntervalSet label() { return IntervalSet.of(from,to); }
|
||||
|
||||
@Override
|
||||
public String toString() {
|
||||
return Target.getANTLRCharLiteralForChar(from)+".."+
|
||||
|
|
|
@ -1,14 +1,13 @@
|
|||
package org.antlr.v4.automata;
|
||||
|
||||
import org.antlr.v4.misc.IntSet;
|
||||
import org.antlr.v4.misc.IntervalSet;
|
||||
|
||||
/** A label containing a set of values */
|
||||
public class SetTransition extends Transition {
|
||||
/** A set of token types or character codes if label==SET */
|
||||
protected IntSet label;
|
||||
protected IntervalSet label;
|
||||
|
||||
public SetTransition(IntSet label) {
|
||||
public SetTransition(IntervalSet label) {
|
||||
if ( label==null ) {
|
||||
this.label = IntervalSet.of(Label.INVALID);
|
||||
return;
|
||||
|
@ -16,6 +15,8 @@ public class SetTransition extends Transition {
|
|||
this.label = label;
|
||||
}
|
||||
|
||||
public IntervalSet label() { return label; }
|
||||
|
||||
public int compareTo(Object o) {
|
||||
return 0;
|
||||
}
|
||||
|
|
|
@ -1,5 +1,6 @@
|
|||
package org.antlr.v4.automata;
|
||||
|
||||
import org.antlr.v4.misc.IntervalSet;
|
||||
import org.antlr.v4.tool.Grammar;
|
||||
|
||||
/** An NFA transition between any two NFA states. Subclasses define
|
||||
|
@ -25,5 +26,7 @@ public abstract class Transition implements Comparable {
|
|||
/** Are we epsilon, action, sempred? */
|
||||
public boolean isEpsilon() { return false; }
|
||||
|
||||
public IntervalSet label() { return null; }
|
||||
|
||||
public String toString(Grammar g) { return toString(); }
|
||||
}
|
||||
|
|
|
@ -48,7 +48,7 @@ public class DOTGenerator {
|
|||
Utils.integer(startState.stateNumber));
|
||||
walkRuleNFACreatingDOT(dot, startState);
|
||||
dot.add("rankdir", rankdir);
|
||||
return dot.toString();
|
||||
return dot.render();
|
||||
}
|
||||
|
||||
public String getDOT(DFAState startState) {
|
||||
|
@ -65,24 +65,9 @@ public class DOTGenerator {
|
|||
Boolean.valueOf(Tool.internalOption_ShowNFAConfigsInDFA));
|
||||
walkCreatingDFADOT(dot, (DFAState)startState);
|
||||
dot.add("rankdir", rankdir);
|
||||
return dot.toString();
|
||||
return dot.render();
|
||||
}
|
||||
|
||||
/** Return a String containing a DOT description that, when displayed,
|
||||
* will show the incoming state machine visually. All nodes reachable
|
||||
* from startState will be included.
|
||||
public String getRuleNFADOT(State startState) {
|
||||
// The output DOT graph for visualization
|
||||
ST dot = stlib.getInstanceOf("org/antlr/tool/templates/dot/nfa");
|
||||
|
||||
markedStates = new HashSet();
|
||||
dot.add("startState",
|
||||
Utils.integer(startState.stateNumber));
|
||||
walkRuleNFACreatingDOT(dot, startState);
|
||||
return dot.toString();
|
||||
}
|
||||
*/
|
||||
|
||||
/** Do a depth-first walk of the state machine graph and
|
||||
* fill a DOT description template. Keep filling the
|
||||
* states and edges attributes.
|
||||
|
|
Loading…
Reference in New Issue