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1 package ro.infoiasi.donald.compiler.parser;
2
3 import ro.infoiasi.donald.compiler.cfg.*;
4
5 import java.io.*;
6 import java.util.*;
7
8 public class CodeWriter {
9 public String  prefix = "SJCC$";
10
11 public static final int LALR1_PARSER = 0;
12 public static final int LR1_PARSER = 1;
13 public static final int SLR1_PARSER = 2;
14
15 private String packageName;
16 private List imports;
17 private String actionCode;
18 private String parserCode;
19 private String initCode;
20 private String scanCode;
21 private CFG g;
22 private NonTerminals v;
23 private Terminals t;
24 private NonTerminal s;
25 private Productions p;
26 private Production sp;
27
28 private String parserClassName = "Parser";
29 private String symbolClassName = "Token";
30
31 private AbstractLR1Parser lr1Parser;
32
33 public CodeWriter(ParserSpec spec, int parserType,
34 String _parserClassName, String _symbolClassName) {
35 packageName = spec.getPackageName();
36 imports = spec.getImports();
37 actionCode = spec.getActionCode();
38 parserCode = spec.getParserCode();
39 initCode = spec.getInitCode();
40 scanCode = spec.getScanCode();
41 g = spec.getGrammar();
42 v = g.getNonTerminals();
43 t = g.getTerminals();
44 s = g.getStartSymbol();
45 p = g.getProductions();
46
47 switch (parserType) {
48 case LALR1_PARSER:
49 lr1Parser = new LALR1Parser(spec); break;
50 case LR1_PARSER:
51 lr1Parser = new LR1Parser(spec); break;
52 case SLR1_PARSER:
53 lr1Parser = new SLR1Parser(spec); break;
54 default:
55 throw new RuntimeException ("Unknown LR1 parser type");
56 }
57 lr1Parser.precompute();
58 sp = lr1Parser.getStartProduction();
59
60 if (_parserClassName != null) {
61 this.parserClassName = _parserClassName;
62 }
63
64 if (_symbolClassName != null) {
65 this.symbolClassName = _symbolClassName;
66 }
67
68 }
69
70 private String pre(String str) {
71 return prefix + parserClassName + "$" + str;
72 }
73
74 public void generateSymbolClass(PrintWriter out) {
75 generatePackage(out);
76 out.println("public interface "+symbolClassName+" {");
77 Iterator it = g.getTerminals().iterator();
78 while (it.hasNext()) {
79 Terminal a = (Terminal)it.next();
80 out.println("\tint "+a.getName()+" = "+g.getSID(a)+";");
81 }
82 out.println("}");
83 }
84
85 public void generateParser(PrintWriter out) {
86 generatePackage(out);
87 generateImports(out);
88 generateParserClass(out);
89 generateActionClass(out);
90 }
91
92 private void generatePackage(PrintWriter out) {
93 if (packageName != null) {
94 out.println("package "+packageName+";");
95 out.println();
96 }
97 }
98
99 private void generateImports(PrintWriter out) {
100 Iterator it = imports.iterator();
101 while (it.hasNext()) {
102 out.println("import "+it.next()+";");
103 }
104 if (!imports.isEmpty()) {
105 out.println();
106 }
107 }
108
109 private void generateParserClass(PrintWriter out) {
110 out.println();
111 out.println("public class "+parserClassName+
112 " extends SkeletonLRParser {");
113 out.println("\tpublic "+parserClassName+"() {");
114 out.println("\t\tsuper();");
115 out.println("\t}");
116 out.println();
117 out.println("\tpublic "+parserClassName+"(parser.runtime.Lexer lex) {");
118 out.println("\t\tsuper(lex);");
119 out.println("\t}");
120 out.println();
121 generateProductionTable(out);
122 out.println();
123 generateActionTable(out);
124 out.println();
125 generateGotoTable(out);
126 out.println();
127 out.println("\tprotected "+pre("Actions")+" actionObject;");
128 out.println();
129 out.println("\tprotected void initActions() {");
130 out.println("\t\tactionObject = new "+pre("Actions")+"(this);");
131 out.println("\t}");
132 out.println();
133 out.println("\tpublic final parser.runtime.StackSymbol doAction (");
134 out.println("\t\t\tint action, "+
135 "parser.runtime.SkeletonLRParser parser,");
136 out.println("\t\t\tjava.util.Stack stack"+
137 ") throws java.lang.Exception {");
138 out.println("\t\treturn actionObject."+pre("doAction")+
139 "(action, parser, stack);");
140 out.println("\t}");
141 out.println();
142 out.println("\tpublic int getStartState() {");
143 out.println("\t\treturn "+lr1Parser.getStartState()+";");
144 out.println("\t}");
145 out.println();
146 out.println("\tpublic int getStartProduction() {");
147 out.println("\t\treturn "+sp.getIndex()+";");
148 out.println("\t}");
149 out.println();
150 out.println("\tpublic int getEOF() {");
151 out.println("\t\treturn "+t.EOF.getIndex()+";");
152 out.println("\t}");
153 out.println("\tpublic int getTokenOffset() {");
154 out.println("\t\treturn "+v.count()+";");
155 out.println("\t}");
156 if (initCode != null) {
157 out.println();
158 out.println("\tpublic int initCode() throws Exception {");
159 out.println(initCode);
160 out.println("\t}");
161 }
162 if (scanCode != null) {
163 out.println();
164 out.println("\tpublic int scan() throws Exception {");
165 out.println(scanCode);
166 out.println("\t}");
167 }
168 if (parserCode != null) {
169 out.println();
170 out.println(parserCode);
171 }
172 out.println("}");
173 }
174
175
176 private void generateProductionTable(PrintWriter out) {
177 short[][] table = new short[p.count()][2];
178 Iterator it = p.iterator();
179 while (it.hasNext()) {
180 Production prod = (Production)it.next();
181 table[prod.getIndex()][0] = (short)prod.getLHS().getIndex();
182 table[prod.getIndex()][1] = (short)prod.getRHS().size();
183 }
184 out.println("\tpublic short[][] getProductionTable() {");
185 out.print("\t\treturn unpackFromStrings(");
186 generateTableAsString(out, table);
187 out.println(");\n\t}");
188 }
189
190 private void generateActionTable(PrintWriter out) {
191 int n = lr1Parser.getStateNo();
192 short[][] table = new short[n][t.count()];
193 for (int i = 0; i<n; i++) {
194 Iterator it = t.iterator();
195 while (it.hasNext()) {
196 Terminal a = (Terminal)it.next();
197 short action;
198 AbstractLR1Parser.ParseAction pa = lr1Parser.getAction(i, a);
199 if (pa != null) {
200 if (pa.isShiftAction()) {
201 AbstractLR1Parser.ShiftAction sa =
202 (AbstractLR1Parser.ShiftAction)pa;
203 action = (short)(sa.getStateIndex().intValue()+1);
204 } else {
205 AbstractLR1Parser.ReduceAction ra =
206 (AbstractLR1Parser.ReduceAction)pa;
207 action = (short)(-ra.getProduction().getIndex()-1);
208 }
209 } else {
210 action = 0;
211 }
212 table[i][a.getIndex()] = action;
213 }
214 }
215 out.println("\tpublic short[][] getActionTable() {");
216 out.print("\t\treturn unpackFromStrings(");
217 generateTableAsString(out, table);
218 out.println(");\n\t}");
219 }
220
221 private void generateGotoTable(PrintWriter out) {
222 int n = lr1Parser.getStateNo();
223 short[][] table = new short[n][v.count()];
224 for (int i = 0; i<n; i++) {
225 Iterator it = v.iterator();
226 while (it.hasNext()) {
227 NonTerminal x = (NonTerminal)it.next();
228 table[i][x.getIndex()] = (short)lr1Parser.getGoto(i, x);
229 }
230 }
231 out.println("\tpublic short[][] getGotoTable() {");
232 out.print("\t\treturn unpackFromStrings(");
233 generateTableAsString(out, table);
234 out.println(");\n\t}");
235 }
236
237
238 private void generateActionClass(PrintWriter out) {
239 out.println();
240 out.println("class " + pre("Actions") + " {");
241 if (actionCode != null) {
242 out.println();
243 out.println(actionCode);
244 }
245 out.println("\tprivate final "+parserClassName+" parser;");
246 out.println();
247 out.println("\t"+pre("Actions")+"("+parserClassName+" parser) {");
248 out.println("\t\tthis.parser = parser;");
249 out.println("\t}");
250 out.println("");
251 out.println("\tpublic final parser.runtime.StackSymbol "+
252 pre("doAction")+"(\n\t\t\tint "+pre("action")+
253 ",\n\t\t\tparser.runtime.SkeletonLRParser "+pre("parser")+
254 ",\n\t\t\tjava.util.Stack "+pre("stack")+
255 ") throws java.lang.Exception {");
256 out.println();
258 out.println("\t\tswitch ("+pre("action")+") {");
259 Iterator it = p.iterator();
260 while (it.hasNext()) {
261 Production prod = (Production)it.next();
262 out.println("\t\t\tcase "+prod.getIndex()+": // "+prod.toString());
263 out.println("\t\t\t{");
264 String resultType = prod.getLHS().getType();
265 if (resultType == null) {
266 resultType = "java.lang.Object";
267 }
268 out.println("\t\t\t\t"+resultType+" RESULT = null;");
269 Word w = prod.getRHS();
270 int j = 0;
271 WordIterator wordIt = w.iterator();
272 while (wordIt.hasNext()) {
273 Symbol sym = (Symbol)wordIt.next();
274 if (!sym.isTerminal() && sym.getName().indexOf("$ACTION") == 0) {
275 int off = w.size()-j-1;
276 out.println("\t\t\t\t// propagate RESULT from "+
277 sym.getName());
278 String temp = "((parser.runtime.StackSymbol) "+pre("stack")+
279 ".elementAt("+pre("stack")+".size()-"+off+")).value";
280 out.println("\t\t\t\tif ("+temp+" != null) {");
281 out.println("\t\t\t\t\tRESULT = "+temp+";");
282 out.println("\t\t\t\t}");
283 }
284 j++;
285 }
286 SemanticAction sa = prod.getSemanticAction();
287 if (sa != null && sa.getCode() != null && sa.getCode().length()>0) {
288 Iterator labelIt = sa.getLabels().iterator();
289 while (labelIt.hasNext()) {
290 Label label = (Label)labelIt.next();
291 int off = sa.getOffset()-label.getPosition();
292 String temp = "((parser.runtime.StackSymbol)"+pre("stack")+
293 ".elementAt("+pre("stack")+".size()-"+off+"))";
294 String type = label.getSymbol().getType();
299 if (type == null) {
300 type = "java.lang.Object";
301 }
302 out.println("\t\t\t\t"+type+" "+label.getName()+
303 " = ("+type+")"+temp+".value;");
304 }
305 out.println(sa.getCode());
306 }
307 if (prod == sp) {
308 out.println("\t\t\t\tparser.doneParsing();");
309 }
310 out.println("\t\t\t\treturn new parser.runtime.StackSymbol("+
312 g.getSID(prod.getLHS())+" /*"+
313 prod.getLHS().getName()+"*/, RESULT);");
314 out.println("\t\t\t}");
315 }
316 out.println("\t\t\tdefault:");
317 out.println("\t\t\t\tthrow new Exception(\"Invalid action number\");");
318 out.println("\t\t}"); out.println("\t}"); out.println("}");
321 }
322
323
324 private void generateTableAsString(PrintWriter out, short[][] sa) {
325 out.println("new String[] {");
326 out.print("\t\t\"");
327 int nchar = 0, nbytes = 0;
328 nbytes += generateEscapedChar(out, (char)(sa.length>>16));
329 nchar = generateNewline(out, nchar, nbytes);
330 nbytes += generateEscapedChar(out, (char)(sa.length&0xFFFF));
331 nchar = generateNewline(out, nchar, nbytes);
332 for (int i = 0; i<sa.length; i++) {
333 nbytes += generateEscapedChar(out, (char)(sa[i].length>>16));
334 nchar = generateNewline(out, nchar, nbytes);
335 nbytes += generateEscapedChar(out, (char)(sa[i].length&0xFFFF));
336 nchar = generateNewline(out, nchar, nbytes);
337 for (int j = 0; j<sa[i].length; j++) {
338 nbytes += generateEscapedChar(out, (char)(2+sa[i][j]));
341 nchar = generateNewline(out, nchar, nbytes);
342 }
343 }
344 out.print("\" }");
345 }
346
347 private int generateNewline(PrintWriter out, int nchar, int nbytes) {
348 if (nbytes > 65500) {
349 out.println("\", "); out.print("\t\t\"");
350 return 0;
351 } else if (nchar > 11) {
352 out.println("\" +"); out.print("\t\t\"");
353 return 0;
354 } else {
355 return nchar+1;
356 }
357 }
358
359 private int generateEscapedChar(PrintWriter out, char c) {
360 StringBuffer escape = new StringBuffer ();
361 if (c <= 0xFF) {
362 escape.append(Integer.toOctalString(c));
363 while(escape.length() < 3) escape.insert(0, '0');
364 } else {
365 escape.append(Integer.toHexString(c));
366 while(escape.length() < 4) escape.insert(0, '0');
367 escape.insert(0, 'u');
368 }
369 escape.insert(0, '\\');
370 out.print(escape.toString());
371
372 if (c == 0) {
373 return 2;
374 } else if (c >= 0x01 && c <= 0x7F) {
375 return 1;
376 } else if (c >= 0x80 && c <= 0x7FF) {
377 return 2;
378 } else {
379 return 3;
380 }
381 }
382 }
383 |
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