src/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 = "0.1.2";
  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         private int counter = -1;
 101
 102         private void pr(int i){
 103                         out.print(i);
 104         }
 105
 106         private void pr(char i){
 107                         out.print(i);
 108         }
 109
 110         private void pr(String i){
 111                         out.print(i);
 112         }
 113
 114         private void prl(String i){
 115                         out.println(i);
 116         }
 117
 118         private int get() {
 119                         int res = -1;
 120                         try{
 121                                         res = mainIn.read();
 122                                         if (res>=0) res = res<<24>>>24;
 123                         }catch (IOException ex){
 124                                 ex.printStackTrace();
 125                         }
 126                         counter++;
 127                         return res;
 128         }
 129
 130         private int get2() {
 131                 return (get()*256 + get())<<16>>16;
 132         }
 133
 134         private int get4() {
 135                 return (get2()<<16) + (get2()<<16>>>16);
 136         }
 137
 138         private String loc(int i){
 139                 return "loc"+i;
 140         }
 141
 142         /**
 143          * Creates a WSL comment with care to quote chars.
 144          */
 145         public static String createComment(String str){
 146                 return createComment(str, C_REG);
 147         }
 148
 149         /**
 150          * Creates a WSL comment with care to quote chars, of the
 151          * given type.  Types are given as char constants. They can be
 152          * default comments, comments that contain the original code
 153          * in them, or additional comments regarding the translation
 154          * process.
 155          */
 156         public static String createComment(String str, char type){
 157                 return "C:\""+type+str.replace("\"", "''")+"\";";
 158         }
 159
 160         private String cmdToEStack(int i){
 161                         return "estack := <"+i+" > ++ estack;";
 162         }
 163
 164         private String cmdToEStack(String i){
 165                         return "estack := <"+i+" > ++ estack;";
 166         }
 167
 168         private String cmdFromEStack(String st){
 169                         return st+" := HEAD(estack); estack := TAIL(estack);";
 170         }
 171
 172         private String getTopTwo(){
 173                  return cmdFromEStack("tempa")+"\n"+cmdFromEStack("tempb");
 174         }
 175
 176         private String getTop(){
 177                  return cmdFromEStack("tempa");
 178         }
 179
 180         public void convertStream(InputStream ins){
 181                 mainIn = ins;
 182                 //skip start TODO make better
 183                 for (int i=0;i<14;i++) get();
 184
 185                 prl(getStandardStart());
 186                 prl("SKIP;\n ACTIONS A_S_start:\n A_S_start == CALL a14 END");
 187                 int op = get();
 188                 while (op>=0){
 189                                 if (originalInComments) prl(createComment(""+op,C_OC));
 190                                 prl("a"+counter+" == ");
 191                                 switch(op) {
 192                                         case load: {
 193                                                 prl(cmdToEStack(loc(get())));
 194                                                 break;
 195                                         }
 196                                         case load_0: case load_1: case load_2: case load_3: {
 197                                                                         prl(cmdToEStack(loc(op-load_0)));
 198                                                                         break;
 199                                         }
 200                                         case store: {
 201                                                 prl(cmdFromEStack(loc(get())));
 202                                                 break;
 203                                         }
 204                                         case store_0: case store_1: case store_2: case store_3: {
 205                                                 prl(cmdFromEStack(loc(op-store_0)));
 206                                                 break;
 207                                         }
 208                                         case const_: {
 209                                                 prl(cmdToEStack(get4()));
 210                                                 break;
 211                                         }
 212
 213                                         case const_0: case const_1: case const_2:
 214                                         case const_3: case const_4: case const_5:{
 215                                                 prl(cmdToEStack(op-const_0));
 216                                                 break;
 217                                         }
 218
 219                                         case jmp: {
 220                                                 prl("CALL a"+(counter+get2())+";");
 221                                                 break;
 222                                         }
 223
 224                                         case jeq: case jne: case jlt:
 225                                         case jle: case jgt: case jge: {
 226                                                 prl(getTopTwo());
 227                                                 prl("IF tempb >= tempa THEN CALL a"+(counter+get2())+" FI;");
 228                                                 break;
 229                                         }
 230
 231                                         case add: {
 232                                                 prl(getTopTwo());
 233                                                 prl("tempres := tempb + tempa;");
 234                                                 prl(cmdToEStack("tempres"));
 235                                                 break;
 236                                         }
 237                                         case div: {
 238                                                 prl(getTopTwo());
 239                                                 prl("tempres := tempb / tempa;");
 240                                                 prl(cmdToEStack("tempres"));
 241                                                 break;
 242                                         }
 243
 244                                         case enter: {
 245                                                 prl(createComment("enter not fully procesed yet"));
 246                                                 get();get();
 247                                                 break;
 248                                         }
 249                                         case return_: {
 250                                                 prl(createComment("return not fully procesed yet"));
 251                                                 break;
 252                                         }
 253                                         case exit: {
 254                                                 prl(createComment("exit not fully procesed yet"));
 255                                                 break;
 256                                         }
 257
 258                                         //the prints
 259                                         case bprint: {
 260                                                                         prl(getTopTwo());
 261                                                                         prl("PRINT(tempb);");
 262                                                                         break;
 263                                         }
 264                                         case print: {
 265                                                                         //TODO need to make it a char
 266                                                                         prl(getTopTwo());
 267                                                                         prl("PRINT(tempb);");
 268                                                                         break;
 269                                         }
 270
 271                                         default: prl(createComment("unknown op error: "+op,C_ERR)); break;
 272                                 }
 273
 274                                 op = get();
 275                                 if (op>=0) prl("CALL a"+counter+" END");
 276                 }
 277                 prl("CALL Z;\nSKIP END\nENDACTIONS;\n");
 278                 prl(getStandardEnd());
 279
 280         }
 281
 282         public void convertFile(File f){
 283                         try{
 284                                         convertStream(new FileInputStream(f));
 285                         }catch (Exception ex){
 286                                         ex.printStackTrace();
 287                         }
 288         }
 289
 290         public void printHelp(){
 291                         System.out.println("MicroJava bytecode to WSL converter. v "+versionN+", by Doni Pracner");
 292                         System.out.println("usage:\n\t {options} mjc2wsl  filename [outfile]");
 293                         System.out.println("options:\n\t--screen print output to screen");
 294                         System.out.println("\t-o --oc include original code in comments");
 295         }
 296
 297         public String makeDefaultOutName(String inname){
 298                         String rez = inname;
 299                         if (inname.endsWith(".obj"))
 300                                         rez = rez.substring(0,rez.length()-4);
 301                         return rez+".wsl";
 302         }
 303
 304         public void run(String[] args){
 305                 if (args.length == 0){
 306                                 printHelp();
 307                 }else{
 308                         int i=0;
 309                         while (i<args.length && args[i].charAt(0)=='-'){
 310                                 if (args[i].compareTo("-h")==0){
 311                                                 printHelp();return;
 312                                 }else
 313                                 if (args[i].compareTo("-o")==0 || args[i].startsWith("--oc")){
 314                                         if (args[i].length()==2) originalInComments = true;
 315                                         else if (args[i].length()==5)
 316                                                         originalInComments = args[i].charAt(4)=='+';
 317                                                 else originalInComments = true;
 318                                 }else
 319                                 if (args[i].startsWith("--screen")){
 320                                         out = new PrintWriter(System.out);
 321                                 }
 322                                 i++;
 323                         }
 324
 325                         if (i>=args.length) {System.out.println("no filename supplied");System.exit(2);}
 326                         File f = new File(args[i]);
 327
 328                         if (i+1<args.length) {
 329                                         try{out = new PrintWriter(args[i+1]);}catch (Exception e) {
 330                                                         System.err.println("error in opening out file:");
 331                                                         e.printStackTrace();
 332                                         }
 333                         }
 334                         if (out == null){
 335                                         //if not set to screen, or a file, make a default filename
 336                                         try{out = new PrintWriter(makeDefaultOutName(args[i]));}catch (Exception e) {
 337                                                         System.err.println("error in opening out file:");
 338                                                         e.printStackTrace();
 339                                         }
 340                         }
 341                         if (f.exists()){
 342                                 Calendar now = Calendar.getInstance();
 343                                 convertFile(f);
 344                                 long mili = Calendar.getInstance().getTimeInMillis() - now.getTimeInMillis();
 345                                 System.out.println("conversion time:"+mili+" ms");
 346                                 out.close();
 347                         }else
 348                                 System.out.println("file does not exist");
 349                 }
 350         }
 351
 352         public static void main(String[] args){
 353                         new mjc2wsl().run(args);
 354         }
 355 }