Has a similar effect a a GET followed by a CALL */
public static final byte CALLMETHOD = -23;
-
+ /** finish a finally block and carry out whatever instruction initiated the finally block */
+ public static final byte FINALLY_DONE = -24;
+
public static final String[] bytecodeToString = new String[] {
"", "", "LITERAL", "ARRAY", "OBJECT", "NEWFUNCTION", "DECLARE", "TOPSCOPE",
"GET", "GET_PRESERVE", "PUT", "JT", "JF", "JMP", "POP", "CALL", "PUSHKEYS",
- "SWAP", "NEWSCOPE", "OLDSCOPE", "DUP", "LABEL", "LOOP", "CALLMETHOD"
+ "SWAP", "NEWSCOPE", "OLDSCOPE", "DUP", "LABEL", "LOOP", "CALLMETHOD",
+ "FINALLY_DONE"
};
}
OUTER: for(pc=0; pc<size; pc++) {
String label = null;
cx.pc = lastPC = pc;
- switch(op[pc]) {
+ int curOP = op[pc];
+ Object curArg = arg[pc];
+ if(curOP == FINALLY_DONE) {
+ FinallyData fd = (FinallyData) t.pop();
+ if(fd == null) continue OUTER; // NOP
+ curOP = fd.op;
+ curArg = fd.arg;
+ }
+ switch(curOP) {
case LITERAL: t.push(arg[pc]); break;
case OBJECT: t.push(new JS.Obj()); break;
case ARRAY: t.push(new JS.Array(JS.toNumber(arg[pc]).intValue())); break;
case POP: t.pop(); break;
case SWAP: { Object o1 = t.pop(); Object o2 = t.pop(); t.push(o1); t.push(o2); break; }
case DUP: t.push(t.peek()); break;
- case NEWSCOPE: /*s = new JS.Scope(s);*/ break;
- case OLDSCOPE: /*s = s.getParentScope();*/ break;
+ case NEWSCOPE: s = new JS.Scope(s); break;
+ case OLDSCOPE: s = s.getParentScope(); break;
case ASSERT: if (!JS.toBoolean(t.pop())) throw je("assertion failed"); break;
case BITNOT: t.push(new Long(~JS.toLong(t.pop()))); break;
case BANG: t.push(new Boolean(!JS.toBoolean(t.pop()))); break;
case LABEL: break;
case LOOP: {
- t.push(s);
- t.push(new LoopMarker(pc, pc > 0 && op[pc - 1] == LABEL ? (String)arg[pc - 1] : (String)null));
+ t.push(new LoopMarker(pc, pc > 0 && op[pc - 1] == LABEL ? (String)arg[pc - 1] : (String)null,s));
t.push(Boolean.TRUE);
break;
}
while(t.size() > 0) {
Object o = t.pop();
if (o instanceof CallMarker) ee("break or continue not within a loop");
- if (o != null && o instanceof LoopMarker) {
- if (arg[pc] == null || arg[pc].equals(((LoopMarker)o).label)) {
+ if (o instanceof TryMarker) {
+ if(((TryMarker)o).finallyLoc < 0) continue; // no finally block, keep going
+ t.push(new FinallyData(curOP, curArg));
+ s = ((TryMarker)o).scope;
+ pc = ((TryMarker)o).finallyLoc - 1;
+ continue OUTER;
+ }
+ if (o instanceof LoopMarker) {
+ if (curArg == null || curArg.equals(((LoopMarker)o).label)) {
int loopInstructionLocation = ((LoopMarker)o).location;
int endOfLoop = ((Integer)arg[loopInstructionLocation]).intValue() + loopInstructionLocation;
- s = (JS.Scope)t.pop();
- if (op[pc] == CONTINUE) { t.push(s); t.push(o); t.push(Boolean.FALSE); }
- pc = op[pc] == BREAK ? endOfLoop - 1 : loopInstructionLocation;
+ s = ((LoopMarker)o).scope;
+ if (curOP == CONTINUE) { t.push(o); t.push(Boolean.FALSE); }
+ pc = curOP == BREAK ? endOfLoop - 1 : loopInstructionLocation;
continue OUTER;
}
}
}
- throw new Error("CONTINUE/BREAK invoked but couldn't find a LoopMarker at " + sourceName + ":" + line);
+ throw new Error("CONTINUE/BREAK invoked but couldn't find a LoopMarker at " + sourceName + ":" + getLine(pc));
case TRY: {
- t.push(new TryMarker(pc + ((Integer)arg[pc]).intValue(), s));
+ int[] jmps = (int[]) arg[pc];
+ // jmps[0] is how far away the catch block is, jmps[1] is how far away the finally block is
+ // each can be < 0 if the specified block does not exist
+ t.push(new TryMarker(jmps[0] < 0 ? -1 : pc + jmps[0], jmps[1] < 0 ? -1 : pc + jmps[1],s));
break;
}
Object retval = t.pop();
while(t.size() > 0) {
Object o = t.pop();
- if (o != null && o instanceof CallMarker) {
+ if (o instanceof TryMarker) {
+ if(((TryMarker)o).finallyLoc < 0) continue;
+ t.push(retval);
+ t.push(new FinallyData(RETURN));
+ s = ((TryMarker)o).scope;
+ pc = ((TryMarker)o).finallyLoc - 1;
+ continue OUTER;
+ }
+ if (o instanceof CallMarker) {
t.push(retval);
return;
}
Object exn = t.pop();
while(t.size() > 0) {
Object o = t.pop();
- if (o instanceof TryMarker) {
- t.push(exn);
- pc = ((TryMarker)o).location - 1;
- s = ((TryMarker)o).scope;
- continue OUTER;
+ if (o instanceof CatchMarker || o instanceof TryMarker) {
+ boolean inCatch = o instanceof CatchMarker;
+ if(inCatch) {
+ o = t.pop();
+ if(((TryMarker)o).finallyLoc < 0) continue; // no finally block, keep going
+ }
+ if(!inCatch && ((TryMarker)o).catchLoc >= 0) {
+ // run the catch block, this will implicitly run the finally block, if it exists
+ t.push(o);
+ t.push(catchMarker);
+ t.push((exn instanceof JS.Exn) ? ((JS.Exn)exn).getObject() : exn);
+ s = ((TryMarker)o).scope;
+ pc = ((TryMarker)o).catchLoc - 1;
+ continue OUTER;
+ } else {
+ t.push(exn);
+ t.push(new FinallyData(THROW));
+ s = ((TryMarker)o).scope;
+ pc = ((TryMarker)o).finallyLoc - 1;
+ continue OUTER;
+ }
+ }
+ // no handler found within this func
+ if(o instanceof CallMarker) {
+ if(exn instanceof JS.Exn)
+ throw (JS.Exn)exn;
+ else
+ throw new JS.Exn(exn);
}
}
- throw new JS.Exn(exn);
+ throw new Error("error: THROW invoked but couldn't find a Try or Call Marker!");
}
case INC: case DEC: {
sb.append(" ");
sb.append(arg[i] == null ? "(no arg)" : arg[i]);
if((op[i] == JF || op[i] == JT || op[i] == JMP) && arg[i] != null && arg[i] instanceof Number) {
- sb.append(" jump to ");
- sb.append(i+((Number) arg[i]).intValue());
+ sb.append(" jump to ").append(i+((Number) arg[i]).intValue());
+ } else if(op[i] == TRY) {
+ int[] jmps = (int[]) arg[i];
+ sb.append(" catch: ").append(jmps[0] < 0 ? "No catch block" : ""+(i+jmps[0]));
+ sb.append(" finally: ").append(jmps[1] < 0 ? "No finally block" : ""+(i+jmps[1]));
}
sb.append("\n");
}
// Markers //////////////////////////////////////////////////////////////////////
public static class CallMarker { public CallMarker() { } }
+
+ public static class CatchMarker { public CatchMarker() { } }
+ private static CatchMarker catchMarker = new CatchMarker();
+
public static class LoopMarker {
public int location;
public String label;
- public LoopMarker(int location, String label) {
+ public JS.Scope scope;
+ public LoopMarker(int location, String label, JS.Scope scope) {
this.location = location;
this.label = label;
+ this.scope = scope;
}
}
public static class TryMarker {
- public int location;
+ public int catchLoc;
+ public int finallyLoc;
public JS.Scope scope;
- public TryMarker(int location, JS.Scope scope) {
- this.location = location;
+ public TryMarker(int catchLoc, int finallyLoc, JS.Scope scope) {
+ this.catchLoc = catchLoc;
+ this.finallyLoc = finallyLoc;
this.scope = scope;
}
}
-
+ public static class FinallyData {
+ public int op;
+ public Object arg;
+ public FinallyData(int op, Object arg) { this.op = op; this.arg = arg; }
+ public FinallyData(int op) { this(op,null); }
+ }
}
/** this class exists solely to work around a GCJ bug */
}
case TRY: {
- b.add(parserLine, TRY);
- int size = b.size();
- parseStatement(b, null); // parse the expression to be TRYed
- b.add(parserLine, POP); // pop the TryMarker
- b.add(parserLine, JMP); // jump forward to the end of the catch block
- int size2 = b.size();
- b.set(size - 1, new Integer(b.size() - size + 1)); // the TRY argument points at the start of the CATCH block
+ b.add(parserLine, TRY); // try bytecode causes a TryMarker to be pushed
+ int tryInsn = b.size() - 1;
+ // parse the expression to be TRYed
+ parseStatement(b, null);
+ // pop the try marker. this is pushed when the TRY bytecode is executed
+ b.add(parserLine, POP);
+ // jump forward to the end of the catch block, start of the finally block
+ b.add(parserLine, JMP);
+ int successJMPInsn = b.size() - 1;
+
+ if (peekToken() != CATCH && peekToken() != FINALLY)
+ throw pe("try without catch or finally");
+ int catchJMPDistance = -1;
if (peekToken() == CATCH) {
+ catchJMPDistance = b.size() - tryInsn;
+ String exceptionVar;
getToken();
consume(LP);
consume(NAME);
+ exceptionVar = string;
consume(RP);
b.add(parserLine, TOPSCOPE); // the exception is on top of the stack; put it to the chosen name
b.add(parserLine, SWAP);
- b.add(parserLine, LITERAL);
+ b.add(parserLine, LITERAL,exceptionVar);
b.add(parserLine, SWAP);
b.add(parserLine, PUT);
b.add(parserLine, POP);
b.add(parserLine, POP);
parseStatement(b, null);
+ // pop the try and catch markers
+ b.add(parserLine,POP);
+ b.add(parserLine,POP);
}
// jump here if no exception was thrown
- b.set(size2 - 1, new Integer(b.size() - size2 + 1));
-
- // FIXME: not implemented correctly
+ b.set(successJMPInsn, new Integer(b.size() - successJMPInsn));
+
+ int finallyJMPDistance = -1;
if (peekToken() == FINALLY) {
+ b.add(parserLine, LITERAL, null); // null FinallyData
+ finallyJMPDistance = b.size() - tryInsn;
consume(FINALLY);
parseStatement(b, null);
+ b.add(parserLine,FINALLY_DONE);
}
+
+ // setup the TRY arguments
+ b.set(tryInsn, new int[] { catchJMPDistance, finallyJMPDistance });
+
break;
}