mjc2wsl process div and rem, with error reporting

[mjc2wsl.git] / src / mjc2wsl.java

diff --git a/src/mjc2wsl.java b/src/mjc2wsl.java
index 970089e..8617713 100644 (file)
--- a/src/mjc2wsl.java
+++ b/src/mjc2wsl.java
@@ -11,15 +11,21 @@ import java.util.*;
  */
 public class mjc2wsl{
        public static String versionN = "0.1.2";
-               
-       //regular comments from the original file
-       //OC when original code is inserted in the file, next to the translations
-       //SPEC special messages from the translator
-       //ERR error messages from the translator
-       public static final char C_REG = ' ', C_OC = '#', C_SPEC = '&', C_ERR = '!';
 
-               /** instruction code */
-               public static final int 
+       /** Constant used for marking a regular comment from the original file */
+       public static final char C_REG = ' ';
+       /**
+        * Constant used for marking when original code is inserted in the file,
+        * next to the translations
+        */
+       public static final char C_OC = '#';
+       /** Constant used for marking special messages from the translator */
+       public static final char C_SPEC = '&';
+       /** Constant used for marking error messages from the translator */
+       public static final char C_ERR = '!';
+
+       /** instruction code in MicroJava bytecode. */
+       public static final int 
                load        =  1,
                load_0      =  2,
                load_1      =  3,
@@ -179,8 +185,20 @@ public class mjc2wsl{
        private String getTop() {
                return cmdFromEStack("tempa");
        }
+       
+       private String getRelationFor(int opcode) throws Exception {
+                       switch (opcode) {
+                                       case jeq: return "=";
+                                       case jne: return "#";
+                                       case jlt: return "<";
+                                       case jle: return "<=";
+                                       case jgt: return ">";
+                                       case jge: return ">=";
+                       }
+                       throw new Exception("Wrong opcode for a relation");
+       }
 
-       public void convertStream(InputStream ins){
+       public void convertStream(InputStream ins) throws Exception{
                mainIn = ins;
                //skip start TODO make better
                for (int i = 0; i < 14; i++)
@@ -243,7 +261,8 @@ public class mjc2wsl{
                        case jgt:
                        case jge: {
                                prl(getTopTwo());
-                               prl("IF tempb >= tempa THEN CALL a" + (counter + get2())
+                               prl("IF tempb "+ getRelationFor(op)
+                                               +" tempa THEN CALL a" + (counter + get2())
                                                + " FI;");
                                break;
                        }
@@ -254,9 +273,29 @@ public class mjc2wsl{
                                prl(cmdToEStack("tempres"));
                                break;
                        }
+                       case sub: {
+                               prl(getTopTwo());
+                               prl("tempres := tempb - tempa;");
+                               prl(cmdToEStack("tempres"));
+                               break;
+                       }
+                       case mul: {
+                               prl(getTopTwo());
+                               prl("tempres := tempb * tempa;");
+                               prl(cmdToEStack("tempres"));
+                               break;
+                       }
                        case div: {
                                prl(getTopTwo());
-                               prl("tempres := tempb / tempa;");
+                               prl("IF tempa = 0 THEN ERROR(\"division by zero\") FI;");
+                               prl("tempres := tempb DIV tempa;");
+                               prl(cmdToEStack("tempres"));
+                               break;
+                       }
+                       case rem: {
+                               prl(getTopTwo());
+                               prl("IF tempa = 0 THEN ERROR(\"division by zero\") FI;");
+                               prl("tempres := tempb MOD tempa;");
                                prl(cmdToEStack("tempres"));
                                break;
                        }