src/mjc2wsl.java

   1 import java.io.*;
   2 import java.util.*;
   3
   4 /**
   5  * This program converts file from compiled MicroJava bytecode to WSL language
   6  * which is a part of the FermaT Transformation system. MicroJava is a subset
   7  * used in Compiler Construction courses by Hanspeter Moessenboeck, not
   8  * "Java ME".
   9  *
  10  * @author Doni Pracner, http://perun.dmi.rs/pracner http://quemaster.com
  11  */
  12 public class mjc2wsl{
  13         public static String versionN = "0.1.3";
  14
  15         public static final int M_ERR = 2, M_WAR = 1, M_DEB = 0;
  16
  17         private int printLevel = M_ERR;
  18
  19         private int[] messageCounters = new int[M_ERR+1];
  20
  21         private void message(String mes, int level){
  22                         if (level>=printLevel)
  23                                         System.out.println(mes);
  24                         messageCounters[level]++;
  25         }
  26
  27         private void printMessageCounters(){
  28                         printMessageCounters(System.out);
  29         }
  30
  31         private void printMessageCounters(PrintStream out){
  32                         out.println("total errors:"+messageCounters[M_ERR]+" warnings:"+messageCounters[M_WAR]);
  33         }
  34
  35         /** Constant used for marking a regular comment from the original file */
  36         public static final char C_REG = ' ';
  37         /**
  38          * Constant used for marking when original code is inserted in the file,
  39          * next to the translations
  40          */
  41         public static final char C_OC = '#';
  42         /** Constant used for marking special messages from the translator */
  43         public static final char C_SPEC = '&';
  44         /** Constant used for marking error messages from the translator */
  45         public static final char C_ERR = '!';
  46
  47         /** instruction code in MicroJava bytecode. */
  48         public static final int
  49                 load        =  1,
  50                 load_0      =  2,
  51                 load_1      =  3,
  52                 load_2      =  4,
  53                 load_3      =  5,
  54                 store       =  6,
  55                 store_0     =  7,
  56                 store_1     =  8,
  57                 store_2     =  9,
  58                 store_3     = 10,
  59                 getstatic   = 11,
  60                 putstatic   = 12,
  61                 getfield    = 13,
  62                 putfield    = 14,
  63                 const_0     = 15,
  64                 const_1     = 16,
  65                 const_2     = 17,
  66                 const_3     = 18,
  67                 const_4     = 19,
  68                 const_5     = 20,
  69                 const_m1    = 21,
  70                 const_      = 22,
  71                 add         = 23,
  72                 sub         = 24,
  73                 mul         = 25,
  74                 div         = 26,
  75                 rem         = 27,
  76                 neg         = 28,
  77                 shl         = 29,
  78                 shr         = 30,
  79                 inc         = 31,
  80                 new_        = 32,
  81                 newarray    = 33,
  82                 aload       = 34,
  83                 astore      = 35,
  84                 baload      = 36,
  85                 bastore     = 37,
  86                 arraylength = 38,
  87                 pop         = 39,
  88                 dup         = 40,
  89                 dup2        = 41,
  90                 jmp         = 42,
  91                 jeq         = 43,
  92                 jne         = 44,
  93                 jlt         = 45,
  94                 jle         = 46,
  95                 jgt         = 47,
  96                 jge         = 48,
  97                 call        = 49,
  98                 return_     = 50,
  99                 enter       = 51,
 100                 exit        = 52,
 101                 read        = 53,
 102                 print       = 54,
 103                 bread       = 55,
 104                 bprint      = 56,
 105                 trap            = 57;
 106
 107         public String getStandardStart(){
 108                 StringBuilder ret = new StringBuilder(
 109                         "C:\" This file automatically converted from microjava bytecode\";\n"
 110                         +"C:\" with mjc2wsl v "+versionN+"\";\n");
 111
 112                 ret.append("VAR < tempa := 0, tempb := 0, tempres :=0,\n\t");
 113                 for (int i = 0; i <= 3; i++)
 114                         ret.append("mjvm_loc" + i + " := 0, ");
 115                 ret.append("\n  mjvm_estack := < >, mjvm_mstack := < >, ");
 116                 ret.append("\n  mjvm_fp := 0, mjvm_sp := 0,");
 117                 ret.append("\n  t_e_m_p := 0 > :");
 118
 119                 return ret.toString();
 120         }
 121
 122         public String getStandardEnd(){
 123                 return "SKIP\nENDVAR";
 124         }
 125
 126         private boolean originalInComments = false;
 127
 128         private InputStream mainIn;
 129         private PrintWriter out = null;
 130         private int counter = -1;
 131
 132         private void pr(int i){
 133                         out.print(i);
 134         }
 135
 136         private void pr(char i){
 137                         out.print(i);
 138         }
 139
 140         private void pr(String i){
 141                         out.print(i);
 142         }
 143
 144         private void prl(String i){
 145                         out.println(i);
 146         }
 147
 148         private int get() {
 149                 int res = -1;
 150                 try {
 151                         res = mainIn.read();
 152                         if (res >= 0)
 153                                 res = res << 24 >>> 24;
 154                 } catch (IOException ex) {
 155                         ex.printStackTrace();
 156                 }
 157                 counter++;
 158                 return res;
 159         }
 160
 161         private int get2() {
 162                 return (get() * 256 + get()) << 16 >> 16;
 163         }
 164
 165         private int get4() {
 166                 return (get2() << 16) + (get2() << 16 >>> 16);
 167         }
 168
 169         private String loc(int i){
 170                 return "mjvm_loc" + i;
 171         }
 172
 173         /**
 174          * Creates a WSL comment with care to quote chars.
 175          */
 176         public static String createComment(String str){
 177                 return createComment(str, C_REG);
 178         }
 179
 180         /**
 181          * Creates a WSL comment with care to quote chars, of the
 182          * given type.  Types are given as char constants. They can be
 183          * default comments, comments that contain the original code
 184          * in them, or additional comments regarding the translation
 185          * process.
 186          */
 187         public static String createComment(String str, char type) {
 188                 return "C:\"" + type + str.replace("\"", "''") + "\";";
 189         }
 190
 191         //Expression stack
 192
 193         private String cmdToEStack(int i) {
 194                 return "mjvm_estack := <" + i + " > ++ mjvm_estack;";
 195         }
 196
 197         private String cmdToEStack(String i) {
 198                 return "mjvm_estack := <" + i + " > ++ mjvm_estack;";
 199         }
 200
 201         private String cmdFromEStack(String st) {
 202                 return st + " := HEAD(mjvm_estack); mjvm_estack := TAIL(mjvm_estack);";
 203         }
 204
 205         private String getTopTwo(){
 206                 return cmdFromEStack("tempa") + "\n" + cmdFromEStack("tempb");
 207         }
 208
 209         private String getTop() {
 210                 return cmdFromEStack("tempa");
 211         }
 212
 213         //Method stack
 214
 215         private String cmdToMStack(int i) {
 216                 return "mjvm_mstack := <" + i + " > ++ mjvm_mstack;";
 217         }
 218
 219         private String cmdToMStack(String i) {
 220                 return "mjvm_mstack := <" + i + " > ++ mjvm_mstack;";
 221         }
 222
 223         private String cmdFromMStack(String st) {
 224                 return st + " := HEAD(mjvm_mstack); mjvm_mstack := TAIL(mjvm_mstack);";
 225         }
 226
 227         private String getRelationFor(int opcode) throws Exception {
 228                         switch (opcode) {
 229                                         case jeq: return "=";
 230                                         case jne: return "<>";
 231                                         case jlt: return "<";
 232                                         case jle: return "<=";
 233                                         case jgt: return ">";
 234                                         case jge: return ">=";
 235                         }
 236                         throw new Exception("Wrong opcode for a relation");
 237         }
 238
 239         public void convertStream(InputStream ins) throws Exception{
 240                 mainIn = ins;
 241                 //skip start TODO make better
 242                 for (int i = 0; i < 14; i++)
 243                         get();
 244
 245                 prl(getStandardStart());
 246                 prl("SKIP;\n ACTIONS A_S_start:\n A_S_start == CALL a14 END");
 247                 int op = get();
 248                 while (op >= 0) {
 249                         if (originalInComments)
 250                                 prl(createComment("" + op, C_OC));
 251                         prl("a" + counter + " == ");
 252                         switch (op) {
 253                         case load: {
 254                                 prl(cmdToEStack(loc(get())));
 255                                 break;
 256                         }
 257                         case load_0:
 258                         case load_1:
 259                         case load_2:
 260                         case load_3: {
 261                                 prl(cmdToEStack(loc(op - load_0)));
 262                                 break;
 263                         }
 264                         case store: {
 265                                 prl(cmdFromEStack(loc(get())));
 266                                 break;
 267                         }
 268                         case store_0:
 269                         case store_1:
 270                         case store_2:
 271                         case store_3: {
 272                                 prl(cmdFromEStack(loc(op - store_0)));
 273                                 break;
 274                         }
 275
 276                         //TODO getstatic, putstatic
 277                         //TODO getfield, putfield
 278
 279                         case const_: {
 280                                 prl(cmdToEStack(get4()));
 281                                 break;
 282                         }
 283
 284                         case const_0:
 285                         case const_1:
 286                         case const_2:
 287                         case const_3:
 288                         case const_4:
 289                         case const_5: {
 290                                 prl(cmdToEStack(op - const_0));
 291                                 break;
 292                         }
 293
 294                         case add: {
 295                                 prl(getTopTwo());
 296                                 prl("tempres := tempb + tempa;");
 297                                 prl(cmdToEStack("tempres"));
 298                                 break;
 299                         }
 300                         case sub: {
 301                                 prl(getTopTwo());
 302                                 prl("tempres := tempb - tempa;");
 303                                 prl(cmdToEStack("tempres"));
 304                                 break;
 305                         }
 306                         case mul: {
 307                                 prl(getTopTwo());
 308                                 prl("tempres := tempb * tempa;");
 309                                 prl(cmdToEStack("tempres"));
 310                                 break;
 311                         }
 312                         case div: {
 313                                 prl(getTopTwo());
 314                                 prl("IF tempa = 0 THEN ERROR(\"division by zero\") FI;");
 315                                 prl("tempres := tempb DIV tempa;");
 316                                 prl(cmdToEStack("tempres"));
 317                                 break;
 318                         }
 319                         case rem: {
 320                                 prl(getTopTwo());
 321                                 prl("IF tempa = 0 THEN ERROR(\"division by zero\") FI;");
 322                                 prl("tempres := tempb MOD tempa;");
 323                                 prl(cmdToEStack("tempres"));
 324                                 break;
 325                         }
 326
 327                         //TODO neg, shl, shr, inc
 328                         //TODO new_ newarray
 329                         //TODO aload, asstore, baload, bastore
 330                         //TODO arraylength
 331                         //TODO pop, dup, dup2
 332
 333                         case jmp: {
 334                                 prl("CALL a" + (counter + get2()) + ";");
 335                                 break;
 336                         }
 337
 338                         case jeq:
 339                         case jne:
 340                         case jlt:
 341                         case jle:
 342                         case jgt:
 343                         case jge: {
 344                                 prl(getTopTwo());
 345                                 prl("IF tempb "+ getRelationFor(op)
 346                                                 +" tempa THEN CALL a" + (counter + get2())
 347                                                 + " FI;");
 348                                 break;
 349                         }
 350
 351                         case call: {
 352                                 prl(cmdToMStack(counter+2));
 353                                 prl("CALL a" + (counter + get2()) + ";");
 354                                 break;
 355                         }
 356
 357                         case return_: {
 358                                 prl("IF EMPTY?(mjvm_mstack) THEN CALL Z ELSE");
 359                                 //else we let things return
 360                                 prl(cmdFromMStack("tempa"));
 361                                 prl("SKIP FI");
 362                                 prl("END b"+counter+" ==");
 363                                 break;
 364                         }
 365                         case enter: {
 366                                 prl(createComment("enter not fully procesed yet"));
 367                                 message("enter not fully procesed yet", M_WAR);
 368                                 get();
 369                                 get();
 370                                 break;
 371                         }
 372                         case exit: {
 373                                 prl(createComment("exit not fully procesed yet"));
 374                                 message("exit not fully procesed yet", M_WAR);
 375                                 break;
 376                         }
 377
 378                         //TODO read, print
 379
 380                         // the prints
 381                         case bprint: {
 382                                 prl(getTopTwo());
 383                                 prl("PRINT(tempb);");
 384                                 break;
 385                         }
 386                         case print: {
 387                                 // TODO need to make it a char
 388                                 prl(getTopTwo());
 389                                 prl("PRINT(tempb);");
 390                                 break;
 391                         }
 392                         default:
 393                                 prl(createComment("unknown op error: " + op, C_ERR));
 394                                 message("unknown op error: "+ op, M_ERR);
 395                                 break;
 396                         }
 397
 398                         //TODO trap
 399
 400
 401                         op = get();
 402                         if (op >= 0)
 403                                 prl("CALL a" + counter + " END");
 404                 }
 405                 prl("CALL Z;\nSKIP END\nENDACTIONS;\n");
 406                 prl(getStandardEnd());
 407
 408         }
 409
 410         public void convertFile(File f) {
 411                 try {
 412                         convertStream(new FileInputStream(f));
 413                 } catch (Exception ex) {
 414                         ex.printStackTrace();
 415                 }
 416         }
 417
 418         public void printHelp() {
 419                 System.out.println("MicroJava bytecode to WSL converter. v " + versionN
 420                                 + ", by Doni Pracner");
 421                 System.out.println("usage:\n\t {options} mjc2wsl  filename [outfile]");
 422                 System.out.println("options:\n\t--screen print output to screen");
 423                 System.out.println("\t-o --oc[+-] include original code in comments");
 424                 System.out.println("\t-v verbose, print warning messages");
 425                 System.out.println("\t-q don't print even the error messages");
 426                 System.out.println("\t-d print detailed debug messages");
 427         }
 428
 429         public String makeDefaultOutName(String inname){
 430                 String rez = inname;
 431                 if (inname.endsWith(".obj"))
 432                         rez = rez.substring(0, rez.length() - 4);
 433                 return rez + ".wsl";
 434         }
 435
 436         public void run(String[] args) {
 437                 if (args.length == 0) {
 438                         printHelp();
 439                 } else {
 440                         int i = 0;
 441                         while (i < args.length && args[i].charAt(0) == '-') {
 442                                 if (args[i].compareTo("-h") == 0) {
 443                                         printHelp();
 444                                         return;
 445                                 } else if (args[i].compareTo("-o") == 0
 446                                                 || args[i].startsWith("--oc")) {
 447                                         if (args[i].length() == 2)
 448                                                 originalInComments = true;
 449                                         else if (args[i].length() == 5)
 450                                                 originalInComments = args[i].charAt(4) == '+';
 451                                         else
 452                                                 originalInComments = true;
 453                                 } else if (args[i].startsWith("--screen")) {
 454                                         out = new PrintWriter(System.out);
 455                                 } else if (args[i].compareTo("-d") == 0) {
 456                                         printLevel = M_DEB;//print debug info
 457                                 } else if (args[i].compareTo("-v") == 0) {
 458                                         printLevel = M_WAR;//print warnings
 459                                 } else if (args[i].compareTo("-q") == 0) {
 460                                         printLevel = M_ERR+1;//no printing
 461                                 }
 462                                 i++;
 463                         }
 464
 465                         if (i >= args.length) {
 466                                 System.out.println("no filename supplied");
 467                                 System.exit(2);
 468                         }
 469                         File f = new File(args[i]);
 470
 471                         if (i + 1 < args.length) {
 472                                 try {
 473                                         out = new PrintWriter(args[i + 1]);
 474                                 } catch (Exception e) {
 475                                         System.err.println("error in opening out file:");
 476                                         e.printStackTrace();
 477                                 }
 478                         }
 479                         if (out == null) {
 480                                 // if not set to screen, or a file, make a default filename
 481                                 try {
 482                                         out = new PrintWriter(makeDefaultOutName(args[i]));
 483                                 } catch (Exception e) {
 484                                         System.err.println("error in opening out file:");
 485                                         e.printStackTrace();
 486                                 }
 487                         }
 488                         if (f.exists()) {
 489                                 Calendar now = Calendar.getInstance();
 490                                 convertFile(f);
 491                                 long mili = Calendar.getInstance().getTimeInMillis()
 492                                                 - now.getTimeInMillis();
 493                                 System.out.println("conversion time:" + mili + " ms");
 494                                 printMessageCounters();
 495                                 out.close();
 496                         } else
 497                                 System.out.println("file does not exist");
 498                 }
 499         }
 500
 501         public static void main(String[] args) {
 502                 new mjc2wsl().run(args);
 503         }
 504 }