mjc2wsl.java

   1 import java.io.*;
   2 import java.util.*;
   3
   4 /**
   5  * This program converts file from compiled MicroJava bytecode (a subset used
   6  * in Compiler Construction courses by H. Moessenboeck, not "Java ME")
   7  * to WSL language which is a part of the FermaT Transformation system.
   8  *
   9  * @author Doni Pracner, http://perun.dmi.rs/pracner http://quemaster.com
  10  */
  11 public class mjc2wsl{
  12         public static String versionN = "0.1";
  13
  14         //regular comments from the original file
  15         //OC when original code is inserted in the file, next to the translations
  16         //SPEC special messages from the translator
  17         //ERR error messages from the transnlator
  18         public static final char C_REG = ' ', C_OC = '#', C_SPEC = '&', C_ERR = '!';
  19
  20
  21                 /** instruction code */
  22                 public static final int
  23                 load        =  1,
  24                 load_0      =  2,
  25                 load_1      =  3,
  26                 load_2      =  4,
  27                 load_3      =  5,
  28                 store       =  6,
  29                 store_0     =  7,
  30                 store_1     =  8,
  31                 store_2     =  9,
  32                 store_3     = 10,
  33                 getstatic   = 11,
  34                 putstatic   = 12,
  35                 getfield    = 13,
  36                 putfield    = 14,
  37                 const_0     = 15,
  38                 const_1     = 16,
  39                 const_2     = 17,
  40                 const_3     = 18,
  41                 const_4     = 19,
  42                 const_5     = 20,
  43                 const_m1    = 21,
  44                 const_      = 22,
  45                 add         = 23,
  46                 sub         = 24,
  47                 mul         = 25,
  48                 div         = 26,
  49                 rem         = 27,
  50                 neg         = 28,
  51                 shl         = 29,
  52                 shr         = 30,
  53                 inc         = 31,
  54                 new_        = 32,
  55                 newarray    = 33,
  56                 aload       = 34,
  57                 astore      = 35,
  58                 baload      = 36,
  59                 bastore     = 37,
  60                 arraylength = 38,
  61                 pop         = 39,
  62                 dup         = 40,
  63                 dup2        = 41,
  64                 jmp         = 42,
  65                 jeq         = 43,
  66                 jne         = 44,
  67                 jlt         = 45,
  68                 jle         = 46,
  69                 jgt         = 47,
  70                 jge         = 48,
  71                 call        = 49,
  72                 return_     = 50,
  73                 enter       = 51,
  74                 exit        = 52,
  75                 read        = 53,
  76                 print       = 54,
  77                 bread       = 55,
  78                 bprint      = 56,
  79                 trap            = 57;
  80
  81         public String getStandardStart(){
  82                 StringBuilder ret = new StringBuilder("C:\" This file automatically converted from microjava bytecode\";\n"
  83                         +"C:\" with mjc2wsl v "+versionN+"\";\n");
  84
  85                 ret.append("VAR < tempa := 0, tempb := 0, tempres :=0,\n");
  86                 for (int i=0;i<=3;i++) ret.append("loc"+i+" := 0, ");
  87                 ret.append("\n  estack := < >, t_e_m_p := 0 > :");
  88
  89                 return ret.toString();
  90         }
  91
  92         public String getStandardEnd(){
  93                 return "SKIP\nENDVAR";
  94         }
  95
  96         private boolean originalInComments = false;
  97
  98         private InputStream mainIn;
  99         private PrintWriter out = null;
 100
 101         private void pr(int i){
 102                         out.print(i);
 103         }
 104
 105         private void pr(char i){
 106                         out.print(i);
 107         }
 108
 109         private void pr(String i){
 110                         out.print(i);
 111         }
 112
 113         private void prl(String i){
 114                         out.println(i);
 115         }
 116
 117         private int get() {
 118                         int res = -1;
 119                         try{
 120                                         res = mainIn.read();
 121                                         if (res>=0) res = res<<24>>>24;
 122                         }catch (IOException ex){
 123                                 ex.printStackTrace();
 124                         }
 125                         return res;
 126         }
 127
 128         private int get2() {
 129                 return (get()*256 + get())<<16>>16;
 130         }
 131
 132         private int get4() {
 133                 return (get2()<<16) + (get2()<<16>>>16);
 134         }
 135
 136         private String loc(int i){
 137                 return "loc"+i;
 138         }
 139
 140         /**
 141          * Creates a WSL comment with care to quote chars.
 142          */
 143         public static String createComment(String str){
 144                 return createComment(str, C_REG);
 145         }
 146
 147         /**
 148          * Creates a WSL comment with care to quote chars, of the
 149          * given type.  Types are given as char constants. They can be
 150          * default comments, comments that contain the original code
 151          * in them, or additional comments regarding the translation
 152          * process.
 153          */
 154         public static String createComment(String str, char type){
 155                 return "C:\""+type+str.replace("\"", "''")+"\";";
 156         }
 157
 158         private String cmdToEStack(int i){
 159                         return "estack := <"+i+" > ++ estack;";
 160         }
 161
 162         private String cmdToEStack(String i){
 163                         return "estack := <"+i+" > ++ estack;";
 164         }
 165
 166         private String cmdFromEStack(String st){
 167                         return st+" := HEAD(estack); estack := TAIL(estack);";
 168         }
 169
 170         private String getTopTwo(){
 171                  return cmdFromEStack("tempa")+"\n"+cmdFromEStack("tempb");
 172         }
 173
 174         private String getTop(){
 175                  return cmdFromEStack("tempa");
 176         }
 177
 178         public void convertStream(InputStream ins){
 179                 mainIn = ins;
 180                 //skip start TODO make better
 181                 for (int i=0;i<14;i++) get();
 182
 183                 prl(getStandardStart());
 184
 185                 int op = get();
 186                 while (op>=0){
 187                                 if (originalInComments) prl(createComment(""+op,C_OC));
 188                                 switch(op) {
 189                                         case load: {
 190                                                 prl(cmdToEStack(loc(get())));
 191                                                 break;
 192                                         }
 193                                         case load_0: case load_1: case load_2: case load_3: {
 194                                                                         prl(cmdToEStack(loc(op-load_0)));
 195                                                                         break;
 196                                         }
 197                                         case store: {
 198                                                 prl(cmdFromEStack(loc(get())));
 199                                                 break;
 200                                         }
 201                                         case store_0: case store_1: case store_2: case store_3: {
 202                                                 prl(cmdFromEStack(loc(op-store_0)));
 203                                                 break;
 204                                         }
 205                                         case const_: {
 206                                                 prl(cmdToEStack(get4()));
 207                                                 break;
 208                                         }
 209
 210                                         case const_0: case const_1: case const_2:
 211                                         case const_3: case const_4: case const_5:{
 212                                                 prl(cmdToEStack(op-const_0));
 213                                                 break;
 214                                         }
 215
 216                                         case jmp: {
 217                                                 prl(createComment("CALL "+get2()));
 218                                                 break;
 219                                         }
 220
 221                                         case jeq: case jne: case jlt:
 222                                         case jle: case jgt: case jge: {
 223                                                 prl(getTopTwo());
 224                                                 prl(createComment("IF CALL "+get2()));
 225                                                 break;
 226                                         }
 227
 228                                         case add: {
 229                                                 prl(getTopTwo());
 230                                                 prl("tempres := tempb + tempa;");
 231                                                 prl(cmdToEStack("tempres"));
 232                                                 break;
 233                                         }
 234                                         case div: {
 235                                                 prl(getTopTwo());
 236                                                 prl("tempres := tempb / tempa;");
 237                                                 prl(cmdToEStack("tempres"));
 238                                                 break;
 239                                         }
 240
 241                                         case enter: {
 242                                                 prl(createComment("enter not fully procesed yet"));
 243                                                 get();get();
 244                                                 break;
 245                                         }
 246                                         case return_: {
 247                                                 prl(createComment("return not fully procesed yet"));
 248                                                 break;
 249                                         }
 250                                         case exit: {
 251                                                 prl(createComment("exit not fully procesed yet"));
 252                                                 break;
 253                                         }
 254
 255                                         //the prints
 256                                         case bprint: {
 257                                                                         prl(getTopTwo());
 258                                                                         prl("PRINT(tempb);");
 259                                                                         break;
 260                                         }
 261                                         case print: {
 262                                                                         //TODO need to make it a char
 263                                                                         prl(getTopTwo());
 264                                                                         prl("PRINT(tempb);");
 265                                                                         break;
 266                                         }
 267
 268                                         default: prl(createComment("unknown op error: "+op,C_ERR)); break;
 269                                 }
 270                                 op = get();
 271                 }
 272                 prl(getStandardEnd());
 273
 274         }
 275
 276         public void convertFile(File f){
 277                         try{
 278                                         convertStream(new FileInputStream(f));
 279                         }catch (Exception ex){
 280                                         ex.printStackTrace();
 281                         }
 282         }
 283
 284         public void printHelp(){
 285                         System.out.println("MicroJava bytecode to WSL converter. v "+versionN+", by Doni Pracner");
 286                         System.out.println("usage:\n\t {options} mjc2wsl  filename [outfile]");
 287                         System.out.println("options:\n\t--screen print output to screen");
 288                         System.out.println("\t-o --oc include original code in comments");
 289         }
 290
 291         public String makeDefaultOutName(String inname){
 292                         String rez = inname;
 293                         if (inname.endsWith(".obj"))
 294                                         rez = rez.substring(0,rez.length()-4);
 295                         return rez+".wsl";
 296         }
 297
 298         public void run(String[] args){
 299                 if (args.length == 0){
 300                                 printHelp();
 301                 }else{
 302                         int i=0;
 303                         while (i<args.length && args[i].charAt(0)=='-'){
 304                                 if (args[i].compareTo("-h")==0){
 305                                                 printHelp();return;
 306                                 }else
 307                                 if (args[i].compareTo("-o")==0 || args[i].startsWith("--oc")){
 308                                         if (args[i].length()==2) originalInComments = true;
 309                                         else if (args[i].length()==5)
 310                                                         originalInComments = args[i].charAt(4)=='+';
 311                                                 else originalInComments = true;
 312                                 }else
 313                                 if (args[i].startsWith("--screen")){
 314                                         out = new PrintWriter(System.out);
 315                                 }
 316                                 i++;
 317                         }
 318
 319                         if (i>=args.length) {System.out.println("no filename supplied");System.exit(2);}
 320                         File f = new File(args[i]);
 321
 322                         if (i+1<args.length) {
 323                                         try{out = new PrintWriter(args[i+1]);}catch (Exception e) {
 324                                                         System.err.println("error in opening out file:");
 325                                                         e.printStackTrace();
 326                                         }
 327                         }
 328                         if (out == null){
 329                                         //if not set to screen, or a file, make a default filename
 330                                         try{out = new PrintWriter(makeDefaultOutName(args[i]));}catch (Exception e) {
 331                                                         System.err.println("error in opening out file:");
 332                                                         e.printStackTrace();
 333                                         }
 334                         }
 335                         if (f.exists()){
 336                                 Calendar now = Calendar.getInstance();
 337                                 convertFile(f);
 338                                 long mili = Calendar.getInstance().getTimeInMillis() - now.getTimeInMillis();
 339                                 System.out.println("conversion time:"+mili+" ms");
 340                                 out.close();
 341                         }else
 342                                 System.out.println("file does not exist");
 343                 }
 344         }
 345
 346         public static void main(String[] args){
 347                         new mjc2wsl().run(args);
 348         }
 349 }