/** A JavaScript function, compiled into bytecode */
public class JSFunction extends JSCallable implements ByteCodes, Tokens {
- /** Note: code gets run in an <i>unpauseable</i> context. */
- public Object call(JSArray args) {
- JSContext cx = new JSContext(this, false);
- cx.invoke(args);
- return cx.stack.pop();
- }
-
// Fields and Accessors ///////////////////////////////////////////////
return ret;
}
- private JSFunction(String sourceName, int firstLine, JSScope parentJSScope) {
+ JSFunction(String sourceName, int firstLine, JSScope parentJSScope) {
this.sourceName = sourceName;
this.firstLine = firstLine;
this.parentJSScope = parentJSScope;
add(-1, LITERAL, null);
add(-1, RETURN);
}
-
+
+ /** Note: code gets run in an <i>unpauseable</i> context. */
+ public Object call(JSArray args) {
+ JSContext cx = new JSContext(this, false);
+ cx.invoke(args);
+ return cx.stack.pop();
+ }
// Adding and Altering Bytecodes ///////////////////////////////////////////////////
}
- // Invoking the Bytecode ///////////////////////////////////////////////////////
-
- /** returns false if the thread has been paused */
- static Object eval(final JSContext cx) throws JS.Exn {
- final int initialPauseCount = cx.pausecount;
- OUTER: for(;; cx.pc++) {
- try {
- if (cx.f == null || cx.pc >= cx.f.size) return cx.stack.pop();
- int op = cx.f.op[cx.pc];
- Object arg = cx.f.arg[cx.pc];
- if(op == FINALLY_DONE) {
- FinallyData fd = (FinallyData) cx.stack.pop();
- if(fd == null) continue OUTER; // NOP
- op = fd.op;
- arg = fd.arg;
- }
- switch(op) {
- case LITERAL: cx.stack.push(arg); break;
- case OBJECT: cx.stack.push(new JSObj()); break;
- case ARRAY: cx.stack.push(new JSArray(JS.toNumber(arg).intValue())); break;
- case DECLARE: cx.scope.declare((String)(arg==null ? cx.stack.peek() : arg)); if(arg != null) cx.stack.push(arg); break;
- case TOPSCOPE: cx.stack.push(cx.scope); break;
- case JT: if (JS.toBoolean(cx.stack.pop())) cx.pc += JS.toNumber(arg).intValue() - 1; break;
- case JF: if (!JS.toBoolean(cx.stack.pop())) cx.pc += JS.toNumber(arg).intValue() - 1; break;
- case JMP: cx.pc += JS.toNumber(arg).intValue() - 1; break;
- case POP: cx.stack.pop(); break;
- case SWAP: {
- int depth = (arg == null ? 1 : toInt(arg));
- Object save = cx.stack.elementAt(cx.stack.size() - 1);
- for(int i=cx.stack.size() - 1; i > cx.stack.size() - 1 - depth; i--)
- cx.stack.setElementAt(cx.stack.elementAt(i-1), i);
- cx.stack.setElementAt(save, cx.stack.size() - depth - 1);
- break; }
- case DUP: cx.stack.push(cx.stack.peek()); break;
- case NEWSCOPE: cx.scope = new JSScope(cx.scope); break;
- case OLDSCOPE: cx.scope = cx.scope.getParentJSScope(); break;
- case ASSERT: if (!JS.toBoolean(cx.stack.pop())) throw je("assertion failed"); break;
- case BITNOT: cx.stack.push(new Long(~JS.toLong(cx.stack.pop()))); break;
- case BANG: cx.stack.push(new Boolean(!JS.toBoolean(cx.stack.pop()))); break;
- case NEWFUNCTION: cx.stack.push(((JSFunction)arg).cloneWithNewParentJSScope(cx.scope)); break;
- case LABEL: break;
-
- case TYPEOF: {
- Object o = cx.stack.pop();
- if (o == null) cx.stack.push(null);
- else if (o instanceof JS) cx.stack.push(((JS)o).typeName());
- else if (o instanceof String) cx.stack.push("string");
- else if (o instanceof Number) cx.stack.push("number");
- else if (o instanceof Boolean) cx.stack.push("boolean");
- else cx.stack.push("unknown");
- break;
- }
-
- case PUSHKEYS: {
- Object o = cx.stack.peek();
- Enumeration e = ((JS)o).keys();
- JSArray a = new JSArray();
- while(e.hasMoreElements()) a.addElement(e.nextElement());
- cx.stack.push(a);
- break;
- }
-
- case LOOP:
- cx.stack.push(new LoopMarker(cx.pc, cx.pc > 0 && cx.f.op[cx.pc - 1] == LABEL ?
- (String)cx.f.arg[cx.pc - 1] : (String)null, cx.scope));
- cx.stack.push(Boolean.TRUE);
- break;
-
- case BREAK:
- case CONTINUE:
- while(cx.stack.size() > 0) {
- Object o = cx.stack.pop();
- if (o instanceof CallMarker) ee("break or continue not within a loop");
- if (o instanceof TryMarker) {
- if(((TryMarker)o).finallyLoc < 0) continue; // no finally block, keep going
- cx.stack.push(new FinallyData(op, arg));
- cx.scope = ((TryMarker)o).scope;
- cx.pc = ((TryMarker)o).finallyLoc - 1;
- continue OUTER;
- }
- if (o instanceof LoopMarker) {
- if (arg == null || arg.equals(((LoopMarker)o).label)) {
- int loopInstructionLocation = ((LoopMarker)o).location;
- int endOfLoop = ((Integer)cx.f.arg[loopInstructionLocation]).intValue() + loopInstructionLocation;
- cx.scope = ((LoopMarker)o).scope;
- if (op == CONTINUE) { cx.stack.push(o); cx.stack.push(Boolean.FALSE); }
- cx.pc = op == BREAK ? endOfLoop - 1 : loopInstructionLocation;
- continue OUTER;
- }
- }
- }
- throw new Error("CONTINUE/BREAK invoked but couldn't find LoopMarker at " +
- cx.getSourceName() + ":" + cx.getLine());
-
- case TRY: {
- int[] jmps = (int[]) arg;
- // 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
- cx.stack.push(new TryMarker(jmps[0] < 0 ? -1 : cx.pc + jmps[0], jmps[1] < 0 ? -1 : cx.pc + jmps[1], cx.scope));
- break;
- }
-
- case RETURN: {
- Object retval = cx.stack.pop();
- while(cx.stack.size() > 0) {
- Object o = cx.stack.pop();
- if (o instanceof TryMarker) {
- if(((TryMarker)o).finallyLoc < 0) continue;
- cx.stack.push(retval);
- cx.stack.push(new FinallyData(RETURN));
- cx.scope = ((TryMarker)o).scope;
- cx.pc = ((TryMarker)o).finallyLoc - 1;
- continue OUTER;
- } else if (o instanceof CallMarker) {
- if (cx.scope instanceof JSTrap.JSTrapScope) {
- JSTrap.JSTrapScope ts = (JSTrap.JSTrapScope)cx.scope;
- if (!ts.cascadeHappened) {
- ts.cascadeHappened = true;
- JSTrap t = ts.t.next;
- while (t != null && t.f.numFormalArgs == 0) t = t.next;
- if (t == null) {
- ((JS)ts.t.trapee).put(t.name, ts.val);
- if (cx.pausecount > initialPauseCount) return null; // we were paused
- } else {
- cx.stack.push(o);
- JSArray args = new JSArray();
- args.addElement(ts.val);
- cx.stack.push(args);
- cx.f = t.f;
- cx.scope = new JSTrap.JSTrapScope(cx.f.parentJSScope, t, ts.val);
- cx.pc = -1;
- break;
- }
- }
- }
- cx.scope = ((CallMarker)o).scope;
- cx.pc = ((CallMarker)o).pc;
- cx.f = (JSFunction)((CallMarker)o).f;
- cx.stack.push(retval);
- continue OUTER;
- }
- }
- throw new Error("error: RETURN invoked but couldn't find a CallMarker!");
- }
-
- case PUT: {
- Object val = cx.stack.pop();
- Object key = cx.stack.pop();
- Object target = cx.stack.peek();
- if (target == null)
- throw je("tried to put a value to the " + key + " property on the null value");
- if (!(target instanceof JS))
- throw je("tried to put a value to the " + key + " property on a " + target.getClass().getName());
- if (key == null)
- throw je("tried to assign \"" + (val==null?"(null)":val.toString()) + "\" to the null key");
- JSTrap t = null;
- if (target instanceof JSTrap.JSTrappable) {
- t = ((JSTrap.JSTrappable)target).getTrap(val);
- while (t != null && t.f.numFormalArgs == 0) t = t.next;
- } else if (target instanceof JSTrap.JSTrapScope && key.equals("cascade")) {
- JSTrap.JSTrapScope ts = (JSTrap.JSTrapScope)target;
- t = ts.t.next;
- ts.cascadeHappened = true;
- while (t != null && t.f.numFormalArgs == 0) t = t.next;
- if (t == null) target = ts.t.trapee;
- }
- if (t != null) {
- cx.stack.push(new CallMarker(cx));
- JSArray args = new JSArray();
- args.addElement(val);
- cx.stack.push(args);
- cx.f = t.f;
- cx.scope = new JSTrap.JSTrapScope(cx.f.parentJSScope, t, val);
- cx.pc = -1;
- break;
- }
- ((JS)target).put(key, val);
- if (cx.pausecount > initialPauseCount) return null; // we were paused
- cx.stack.push(val);
- break;
- }
-
- case GET:
- case GET_PRESERVE: {
- Object o, v;
- if (op == GET) {
- v = arg == null ? cx.stack.pop() : arg;
- o = cx.stack.pop();
- } else {
- v = cx.stack.pop();
- o = cx.stack.peek();
- cx.stack.push(v);
- }
- Object ret = null;
- if (v == null) throw je("tried to get the null key from " + o);
- if (o == null) throw je("tried to get property \"" + v + "\" from the null value @" + cx.pc + "\n" + cx.f.dump());
- if (o instanceof String || o instanceof Number || o instanceof Boolean) {
- ret = Internal.getFromPrimitive(o,v);
- cx.stack.push(ret);
- break;
- } else if (o instanceof JS) {
- JSTrap t = null;
- if (o instanceof JSTrap.JSTrappable) {
- t = ((JSTrap.JSTrappable)o).getTrap(v);
- while (t != null && t.f.numFormalArgs != 0) t = t.next;
- } else if (o instanceof JSTrap.JSTrapScope && v.equals("cascade")) {
- t = ((JSTrap.JSTrapScope)o).t.next;
- while (t != null && t.f.numFormalArgs != 0) t = t.next;
- if (t == null) o = ((JSTrap.JSTrapScope)o).t.trapee;
- }
- if (t != null) {
- cx.stack.push(new CallMarker(cx));
- JSArray args = new JSArray();
- cx.stack.push(args);
- cx.f = t.f;
- cx.scope = new JSTrap.JSTrapScope(cx.f.parentJSScope, t, null);
- ((JSTrap.JSTrapScope)cx.scope).cascadeHappened = true;
- cx.pc = -1;
- break;
- }
- ret = ((JS)o).get(v);
- if (cx.pausecount > initialPauseCount) return null; // we were paused
- cx.stack.push(ret);
- break;
- }
- throw je("tried to get property " + v + " from a " + o.getClass().getName());
- }
-
- case CALL: case CALLMETHOD: {
- int numArgs = JS.toInt(arg);
- Object method = null;
- Object object = null;
- Object ret = null;
- JSArray arguments = null;
-
- if(op == CALLMETHOD) {
- Object getResult = cx.stack.pop();
- method = cx.stack.pop();
- object = cx.stack.pop();
- if (getResult != null) {
- method = null;
- object = getResult;
- }
- } else {
- method = null;
- object = cx.stack.pop();
- }
-
- if (object instanceof String || object instanceof Number || object instanceof Boolean) {
- arguments = new JSArray(); for(int j=numArgs - 1; j >= 0; j--) arguments.setElementAt(cx.stack.pop(), j);
- ret = Internal.callMethodOnPrimitive(object, method, arguments);
-
- } else if (object instanceof JSFunction) {
- // FEATURE: use something similar to call0/call1/call2 here
- arguments = new JSArray(); for(int j=numArgs - 1; j >= 0; j--) arguments.setElementAt(cx.stack.pop(), j);
- cx.stack.push(new CallMarker(cx));
- cx.stack.push(arguments);
- cx.f = (JSFunction)object;
- cx.scope = new JSScope(cx.f.parentJSScope);
- cx.pc = -1;
- break;
-
- } else if (object instanceof JSCallable) {
- JSCallable c = (JSCallable)object;
- switch(numArgs) {
- case 0: ret = c.call0(method); break;
- case 1: ret = c.call1(method, cx.stack.pop()); break;
- case 2: {
- Object first = cx.stack.pop();
- Object second = cx.stack.pop();
- ret = c.call2(method, second, first);
- break;
- }
- default: {
- arguments = new JSArray();
- for(int j=numArgs - 1; j >= 0; j--) arguments.setElementAt(cx.stack.pop(), j);
- ret = c.call(method, arguments);
- break;
- }
- }
- } else {
- throw new JS.Exn("can't call a " + object.getClass().getName() + " @" + cx.pc + "\n" + cx.f.dump());
- }
- if (cx.pausecount > initialPauseCount) return null;
- cx.stack.push(ret);
- break;
- }
-
- case THROW: {
- Object o = cx.stack.pop();
- if(o instanceof JS.Exn) throw (JS.Exn)o;
- throw new JS.Exn(o);
- }
-
- case ASSIGN_SUB: case ASSIGN_ADD: {
- Object val = cx.stack.pop();
- Object old = cx.stack.pop();
- Object key = cx.stack.pop();
- Object obj = cx.stack.peek();
- if (val instanceof JSFunction && obj instanceof JSScope) {
- JSScope parent = (JSScope)obj;
- while(parent.getParentJSScope() != null) parent = parent.getParentJSScope();
- if (parent instanceof JSTrap.JSTrappable) {
- JSTrap.JSTrappable b = (JSTrap.JSTrappable)parent;
- if (op == ASSIGN_ADD) JSTrap.addTrap(b, key, (JSFunction)val);
- else JSTrap.delTrap(b, key, (JSFunction)val);
- // skip over the "normal" implementation of +=/-=
- cx.pc += ((Integer)arg).intValue() - 1;
- break;
- }
- }
- // use the "normal" implementation
- cx.stack.push(key);
- cx.stack.push(old);
- cx.stack.push(val);
- break;
- }
-
- case ADD: {
- int count = ((Number)arg).intValue();
- if(count < 2) throw new Error("this should never happen");
- if(count == 2) {
- // common case
- Object right = cx.stack.pop();
- Object left = cx.stack.pop();
- if(left instanceof String || right instanceof String)
- cx.stack.push(JS.toString(left).concat(JS.toString(right)));
- else cx.stack.push(new Double(JS.toDouble(left) + JS.toDouble(right)));
- } else {
- Object[] args = new Object[count];
- while(--count >= 0) args[count] = cx.stack.pop();
- if(args[0] instanceof String) {
- StringBuffer sb = new StringBuffer(64);
- for(int i=0;i<args.length;i++) sb.append(JS.toString(args[i]));
- cx.stack.push(sb.toString());
- } else {
- int numStrings = 0;
- for(int i=0;i<args.length;i++) if(args[i] instanceof String) numStrings++;
- if(numStrings == 0) {
- double d = 0.0;
- for(int i=0;i<args.length;i++) d += JS.toDouble(args[i]);
- cx.stack.push(new Double(d));
- } else {
- int i=0;
- StringBuffer sb = new StringBuffer(64);
- if(!(args[0] instanceof String || args[1] instanceof String)) {
- double d=0.0;
- do {
- d += JS.toDouble(args[i++]);
- } while(!(args[i] instanceof String));
- sb.append(JS.toString(new Double(d)));
- }
- while(i < args.length) sb.append(JS.toString(args[i++]));
- cx.stack.push(sb.toString());
- }
- }
- }
- break;
- }
-
- default: {
- Object right = cx.stack.pop();
- Object left = cx.stack.pop();
- switch(op) {
-
- case BITOR: cx.stack.push(new Long(JS.toLong(left) | JS.toLong(right))); break;
- case BITXOR: cx.stack.push(new Long(JS.toLong(left) ^ JS.toLong(right))); break;
- case BITAND: cx.stack.push(new Long(JS.toLong(left) & JS.toLong(right))); break;
-
- case SUB: cx.stack.push(new Double(JS.toDouble(left) - JS.toDouble(right))); break;
- case MUL: cx.stack.push(new Double(JS.toDouble(left) * JS.toDouble(right))); break;
- case DIV: cx.stack.push(new Double(JS.toDouble(left) / JS.toDouble(right))); break;
- case MOD: cx.stack.push(new Double(JS.toDouble(left) % JS.toDouble(right))); break;
-
- case LSH: cx.stack.push(new Long(JS.toLong(left) << JS.toLong(right))); break;
- case RSH: cx.stack.push(new Long(JS.toLong(left) >> JS.toLong(right))); break;
- case URSH: cx.stack.push(new Long(JS.toLong(left) >>> JS.toLong(right))); break;
-
- case LT: case LE: case GT: case GE: {
- if (left == null) left = new Integer(0);
- if (right == null) right = new Integer(0);
- int result = 0;
- if (left instanceof String || right instanceof String) {
- result = left.toString().compareTo(right.toString());
- } else {
- result = (int)java.lang.Math.ceil(JS.toDouble(left) - JS.toDouble(right));
- }
- cx.stack.push(new Boolean((op == LT && result < 0) || (op == LE && result <= 0) ||
- (op == GT && result > 0) || (op == GE && result >= 0)));
- break;
- }
-
- case EQ:
- case NE: {
- Object l = left;
- Object r = right;
- boolean ret;
- if (l == null) { Object tmp = r; r = l; l = tmp; }
- if (l == null && r == null) ret = true;
- else if (r == null) ret = false; // l != null, so its false
- else if (l instanceof Boolean) ret = new Boolean(JS.toBoolean(r)).equals(l);
- else if (l instanceof Number) ret = JS.toNumber(r).doubleValue() == JS.toNumber(l).doubleValue();
- else if (l instanceof String) ret = r != null && l.equals(r.toString());
- else ret = l.equals(r);
- cx.stack.push(new Boolean(op == EQ ? ret : !ret)); break;
- }
-
- default: throw new Error("unknown opcode " + op);
- } }
- }
-
- } catch(JS.Exn e) {
- while(cx.stack.size() > 0) {
- Object o = cx.stack.pop();
- if (o instanceof CatchMarker || o instanceof TryMarker) {
- boolean inCatch = o instanceof CatchMarker;
- if(inCatch) {
- o = cx.stack.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
- cx.stack.push(o);
- cx.stack.push(catchMarker);
- cx.stack.push(e.getObject());
- cx.scope = ((TryMarker)o).scope;
- cx.pc = ((TryMarker)o).catchLoc - 1;
- continue OUTER;
- } else {
- cx.stack.push(e);
- cx.stack.push(new FinallyData(THROW));
- cx.scope = ((TryMarker)o).scope;
- cx.pc = ((TryMarker)o).finallyLoc - 1;
- continue OUTER;
- }
- }
- // no handler found within this func
- if(o instanceof CallMarker) throw e;
- }
- throw e;
- } // end try/catch
- } // end for
- }
-
-
// Debugging //////////////////////////////////////////////////////////////////////
public String toString() { return "JSFunction [" + sourceName + ":" + firstLine + "]"; }
}
- // Exception Stuff ////////////////////////////////////////////////////////////////
-
- static class EvaluatorException extends RuntimeException { public EvaluatorException(String s) { super(s); } }
- static EvaluatorException ee(String s) {
- throw new EvaluatorException(JSContext.getSourceName() + ":" + JSContext.getLine() + " " + s);
- }
- static JS.Exn je(String s) {
- throw new JS.Exn(JSContext.getSourceName() + ":" + JSContext.getLine() + " " + s);
- }
-
-
- // Markers //////////////////////////////////////////////////////////////////////
-
- public static class CallMarker {
- int pc;
- JSScope scope;
- JSFunction f;
- public CallMarker(JSContext cx) { pc = cx.pc + 1; scope = cx.scope; f = cx.f; }
- }
-
- public static class CatchMarker { public CatchMarker() { } }
- private static CatchMarker catchMarker = new CatchMarker();
-
- public static class LoopMarker {
- public int location;
- public String label;
- public JSScope scope;
- public LoopMarker(int location, String label, JSScope scope) {
- this.location = location;
- this.label = label;
- this.scope = scope;
- }
- }
- public static class TryMarker {
- public int catchLoc;
- public int finallyLoc;
- public JSScope scope;
- public TryMarker(int catchLoc, int finallyLoc, JSScope 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); }
- }
}
projects / org.ibex.core.git / blobdiff