1 // Copyright 2003 Adam Megacz, see the COPYING file for licensing [GPL]
7 // FIXME: could use some cleaning up
8 /** a JavaScript function, compiled into bytecode */
9 class CompiledFunctionImpl extends JSCallable implements ByteCodes, Tokens {
11 // Fields and Accessors ///////////////////////////////////////////////
13 /** the source code file that this block was drawn from */
14 private String sourceName;
15 public String getSourceName() throws JS.Exn { return sourceName; }
17 /** the line numbers */
18 private int[] line = new int[10];
20 /** the first line of this script */
21 private int firstLine = -1;
23 /** the instructions */
24 private int[] op = new int[10];
26 /** the arguments to the instructions */
27 private Object[] arg = new Object[10];
29 /** the number of instruction/argument pairs */
31 int size() { return size; }
33 /** the scope in which this function was declared; by default this function is called in a fresh subscope of the parentScope */
34 private JS.Scope parentScope;
36 // Constructors ////////////////////////////////////////////////////////
38 private CompiledFunctionImpl cloneWithNewParentScope(JS.Scope s) throws IOException {
39 CompiledFunctionImpl ret = new JS.CompiledFunction(sourceName, firstLine, null, s);
40 // Reuse the same op, arg, line, and size variables for the new "instance" of the function
41 // NOTE: Neither *this* function nor the new function should be modified after this call
49 protected CompiledFunctionImpl(String sourceName, int firstLine, Reader sourceCode, JS.Scope parentScope) throws IOException {
50 this.sourceName = sourceName;
51 this.firstLine = firstLine;
52 this.parentScope = parentScope;
53 if (sourceCode == null) return;
54 Parser p = new Parser(sourceCode, sourceName, firstLine);
57 p.parseStatement(this, null);
58 if (s == size()) break;
60 add(-1, LITERAL, null);
64 public Object call(JS.Array args) throws JS.Exn { return call(args, new FunctionScope(sourceName, parentScope)); }
65 public Object call(JS.Array args, JS.Scope scope) throws JS.Exn {
66 JS.Thread cx = JS.Thread.fromJavaThread(java.lang.Thread.currentThread());
67 CompiledFunction saved = cx.currentCompiledFunction;
69 cx.currentCompiledFunction = (CompiledFunction)this;
70 int size = cx.stack.size();
71 cx.stack.push(callMarker);
74 Object ret = cx.stack.pop();
75 if (cx.stack.size() > size)
76 // this should never happen
77 throw new Error("ERROR: stack grew by " + (cx.stack.size() - size) + " elements during call at " + sourceName + ":" + firstLine);
81 while(cx.stack.size() > 0) if(cx.stack.pop() instanceof CallMarker) throw e;
82 throw new Error("CallMarker not found on the stack"); // should never happen
84 cx.currentCompiledFunction = saved;
89 // Adding and Altering Bytecodes ///////////////////////////////////////////////////
91 int get(int pos) { return op[pos]; }
92 Object getArg(int pos) { return arg[pos]; }
93 void set(int pos, int op_, Object arg_) { op[pos] = op_; arg[pos] = arg_; }
94 void set(int pos, Object arg_) { arg[pos] = arg_; }
95 int pop() { size--; arg[size] = null; return op[size]; }
96 void paste(CompiledFunctionImpl other) { for(int i=0; i<other.size; i++) add(other.line[i], other.op[i], other.arg[i]); }
97 CompiledFunctionImpl add(int line, int op_) { return add(line, op_, null); }
98 CompiledFunctionImpl add(int line, int op_, Object arg_) {
99 if (size == op.length - 1) {
100 int[] line2 = new int[op.length * 2]; System.arraycopy(this.line, 0, line2, 0, op.length); this.line = line2;
101 Object[] arg2 = new Object[op.length * 2]; System.arraycopy(arg, 0, arg2, 0, arg.length); arg = arg2;
102 int[] op2 = new int[op.length * 2]; System.arraycopy(op, 0, op2, 0, op.length); op = op2;
104 this.line[size] = line;
111 public int getLine(int pc) {
112 if(pc < 0 || pc >= size) return -1;
117 // Invoking the Bytecode ///////////////////////////////////////////////////////
119 void eval(JS.Scope s) {
120 final JS.Thread cx = JS.Thread.fromJavaThread(java.lang.Thread.currentThread());
121 final Vec t = cx.stack;
124 OUTER: for(pc=0; pc<size; pc++) {
129 Object curArg = arg[pc];
130 if(curOP == FINALLY_DONE) {
131 FinallyData fd = (FinallyData) t.pop();
132 if(fd == null) continue OUTER; // NOP
137 case LITERAL: t.push(arg[pc]); break;
138 case OBJECT: t.push(new JS.Obj()); break;
139 case ARRAY: t.push(new JS.Array(JS.toNumber(arg[pc]).intValue())); break;
140 case DECLARE: s.declare((String)(arg[pc]==null ? t.peek() : arg[pc])); if(arg[pc] != null) t.push(arg[pc]); break;
141 case TOPSCOPE: t.push(s); break;
142 case JT: if (JS.toBoolean(t.pop())) pc += JS.toNumber(arg[pc]).intValue() - 1; break;
143 case JF: if (!JS.toBoolean(t.pop())) pc += JS.toNumber(arg[pc]).intValue() - 1; break;
144 case JMP: pc += JS.toNumber(arg[pc]).intValue() - 1; break;
145 case POP: t.pop(); break;
146 case SWAP: { Object o1 = t.pop(); Object o2 = t.pop(); t.push(o1); t.push(o2); break; }
147 case DUP: t.push(t.peek()); break;
148 case NEWSCOPE: s = new JS.Scope(s); break;
149 case OLDSCOPE: s = s.getParentScope(); break;
150 case ASSERT: if (!JS.toBoolean(t.pop())) throw je("assertion failed"); break;
151 case BITNOT: t.push(new Long(~JS.toLong(t.pop()))); break;
152 case BANG: t.push(new Boolean(!JS.toBoolean(t.pop()))); break;
156 if (o == null) t.push(null);
157 else if (o instanceof JS) t.push(((JS)o).typeName());
158 else if (o instanceof String) t.push("string");
159 else if (o instanceof Number) t.push("number");
160 else if (o instanceof Boolean) t.push("boolean");
161 else t.push("unknown");
167 t.push(((CompiledFunctionImpl)arg[pc]).cloneWithNewParentScope(s));
168 } catch (IOException e) {
169 throw new Error("this should never happen");
176 Object[] keys = ((JS)o).keys();
177 JS.Array a = new JS.Array();
178 a.setSize(keys.length);
179 for(int j=0; j<keys.length; j++) a.setElementAt(keys[j], j);
186 t.push(new LoopMarker(pc, pc > 0 && op[pc - 1] == LABEL ? (String)arg[pc - 1] : (String)null,s));
187 t.push(Boolean.TRUE);
193 while(t.size() > 0) {
195 if (o instanceof CallMarker) ee("break or continue not within a loop");
196 if (o instanceof TryMarker) {
197 if(((TryMarker)o).finallyLoc < 0) continue; // no finally block, keep going
198 t.push(new FinallyData(curOP, curArg));
199 s = ((TryMarker)o).scope;
200 pc = ((TryMarker)o).finallyLoc - 1;
203 if (o instanceof LoopMarker) {
204 if (curArg == null || curArg.equals(((LoopMarker)o).label)) {
205 int loopInstructionLocation = ((LoopMarker)o).location;
206 int endOfLoop = ((Integer)arg[loopInstructionLocation]).intValue() + loopInstructionLocation;
207 s = ((LoopMarker)o).scope;
208 if (curOP == CONTINUE) { t.push(o); t.push(Boolean.FALSE); }
209 pc = curOP == BREAK ? endOfLoop - 1 : loopInstructionLocation;
214 throw new Error("CONTINUE/BREAK invoked but couldn't find a LoopMarker at " + sourceName + ":" + getLine(pc));
217 int[] jmps = (int[]) arg[pc];
218 // jmps[0] is how far away the catch block is, jmps[1] is how far away the finally block is
219 // each can be < 0 if the specified block does not exist
220 t.push(new TryMarker(jmps[0] < 0 ? -1 : pc + jmps[0], jmps[1] < 0 ? -1 : pc + jmps[1],s));
225 Object retval = t.pop();
226 while(t.size() > 0) {
228 if (o instanceof TryMarker) {
229 if(((TryMarker)o).finallyLoc < 0) continue;
231 t.push(new FinallyData(RETURN));
232 s = ((TryMarker)o).scope;
233 pc = ((TryMarker)o).finallyLoc - 1;
236 if (o instanceof CallMarker) {
241 throw new Error("error: RETURN invoked but couldn't find a CallMarker!");
245 Object val = t.pop();
246 Object key = t.pop();
247 Object target = t.peek();
249 throw je("tried to put a value to the " + key + " property on the null value");
250 if (!(target instanceof JS))
251 throw je("tried to put a value to the " + key + " property on a " + target.getClass().getName());
253 throw je("tried to assign \"" + (val==null?"(null)":val.toString()) + "\" to the null key");
254 ((JS)target).put(key, val);
263 v = arg[pc] == null ? t.pop() : arg[pc];
271 if (o == null) throw je("tried to get property \"" + v + "\" from the null value");
272 if (v == null) throw je("tried to get the null key from " + o);
273 if (o instanceof String || o instanceof Number || o instanceof Boolean)
274 ret = Internal.getFromPrimitive(o,v);
275 else if (o instanceof JS)
276 ret = ((JS)o).get(v);
278 throw je("tried to get property " + v + " from a " + o.getClass().getName());
286 JS.Array arguments = new JS.Array();
287 int numArgs = JS.toNumber(arg[pc]).intValue();
288 arguments.setSize(numArgs);
289 for(int j=numArgs - 1; j >= 0; j--) arguments.setElementAt(t.pop(), j);
291 if(o == null) throw je("attempted to call null");
293 if(op[pc] == CALLMETHOD) {
296 if(o instanceof String || o instanceof Number || o instanceof Boolean)
297 ret = Internal.callMethodOnPrimitive(o,method,arguments);
298 else if(o instanceof JS)
299 ret = ((JS)o).callMethod(method,arguments,false);
301 throw new JS.Exn("Tried to call a method on an object that isn't a JS object");
303 ret = ((JS.Callable)o).call(arguments);
308 // fall through if exception was thrown
311 if(o instanceof JS.Exn) throw (JS.Exn)o;
315 case INC: case DEC: {
316 boolean isPrefix = JS.toBoolean(arg[pc]);
317 Object key = t.pop();
318 JS obj = (JS)t.pop();
319 Number num = JS.toNumber(obj.get(key));
320 Number val = new Double(op[pc] == INC ? num.doubleValue() + 1.0 : num.doubleValue() - 1.0);
322 t.push(isPrefix ? val : num);
328 int count = ((Number)arg[pc]).intValue();
329 if(count < 2) throw new Error("this should never happen");
332 Object right = t.pop();
333 Object left = t.pop();
334 if(left instanceof String || right instanceof String) t.push(JS.toString(left).concat(JS.toString(right)));
335 else t.push(new Double(JS.toDouble(left) + JS.toDouble(right)));
338 Object[] args = new Object[count];
339 while(--count >= 0) args[count] = t.pop();
340 if(args[0] instanceof String) {
341 StringBuffer sb = new StringBuffer(64);
342 for(int i=0;i<args.length;i++) sb.append(JS.toString(args[i]));
343 t.push(sb.toString());
346 for(int i=0;i<args.length;i++) if(args[i] instanceof String) numStrings++;
347 if(numStrings == 0) {
349 for(int i=0;i<args.length;i++) d += JS.toDouble(args[i]);
350 t.push(new Double(d));
355 d += JS.toDouble(args[i++]);
356 } while(!(args[i] instanceof String));
357 StringBuffer sb = new StringBuffer(64);
358 sb.append(JS.toString(new Double(d)));
359 while(i < args.length) sb.append(JS.toString(args[i++]));
360 t.push(sb.toString());
367 Object right = t.pop();
368 Object left = t.pop();
371 case BITOR: t.push(new Long(JS.toLong(left) | JS.toLong(right))); break;
372 case BITXOR: t.push(new Long(JS.toLong(left) ^ JS.toLong(right))); break;
373 case BITAND: t.push(new Long(JS.toLong(left) & JS.toLong(right))); break;
375 case SUB: t.push(new Double(JS.toDouble(left) - JS.toDouble(right))); break;
376 case MUL: t.push(new Double(JS.toDouble(left) * JS.toDouble(right))); break;
377 case DIV: t.push(new Double(JS.toDouble(left) / JS.toDouble(right))); break;
378 case MOD: t.push(new Double(JS.toDouble(left) % JS.toDouble(right))); break;
380 case LSH: t.push(new Long(JS.toLong(left) << JS.toLong(right))); break;
381 case RSH: t.push(new Long(JS.toLong(left) >> JS.toLong(right))); break;
382 case URSH: t.push(new Long(JS.toLong(left) >>> JS.toLong(right))); break;
384 case LT: case LE: case GT: case GE: {
385 if (left == null) left = new Integer(0);
386 if (right == null) right = new Integer(0);
388 if (left instanceof String || right instanceof String) {
389 result = left.toString().compareTo(right.toString());
391 result = (int)java.lang.Math.ceil(JS.toDouble(left) - JS.toDouble(right));
393 t.push(new Boolean((op[pc] == LT && result < 0) || (op[pc] == LE && result <= 0) ||
394 (op[pc] == GT && result > 0) || (op[pc] == GE && result >= 0)));
403 if (l == null) { Object tmp = r; r = l; l = tmp; }
404 if (l == null && r == null) ret = true;
405 else if (r == null) ret = false; // l != null, so its false
406 else if (l instanceof Boolean) ret = new Boolean(JS.toBoolean(r)).equals(l);
407 else if (l instanceof Number) ret = JS.toNumber(r).doubleValue() == JS.toNumber(l).doubleValue();
408 else if (l instanceof String) ret = r != null && l.equals(r.toString());
409 else ret = l.equals(r);
410 t.push(new Boolean(op[pc] == EQ ? ret : !ret)); break;
413 default: throw new Error("unknown opcode " + op[pc]);
417 while(t.size() > 0) {
419 if (o instanceof CatchMarker || o instanceof TryMarker) {
420 boolean inCatch = o instanceof CatchMarker;
423 if(((TryMarker)o).finallyLoc < 0) continue; // no finally block, keep going
425 if(!inCatch && ((TryMarker)o).catchLoc >= 0) {
426 // run the catch block, this will implicitly run the finally block, if it exists
429 t.push(e.getObject());
430 s = ((TryMarker)o).scope;
431 pc = ((TryMarker)o).catchLoc - 1;
435 t.push(new FinallyData(THROW));
436 s = ((TryMarker)o).scope;
437 pc = ((TryMarker)o).finallyLoc - 1;
441 // no handler found within this func
442 if(o instanceof CallMarker) throw e;
444 throw new Error("couldn't find a Try or Call Marker!");
447 // this should never happen, we will ALWAYS have a RETURN at the end of the func
448 throw new Error("Just fell out of CompiledFunction::eval() loop. Last PC was " + lastPC);
451 // Debugging //////////////////////////////////////////////////////////////////////
453 public String toString() {
454 StringBuffer sb = new StringBuffer(1024);
455 sb.append("\n" + sourceName + ": " + firstLine + "\n");
456 for (int i=0; i < size; i++) {
460 sb.append(bytecodeToString[-op[i]]);
462 sb.append(codeToString[op[i]]);
464 sb.append(arg[i] == null ? "(no arg)" : arg[i]);
465 if((op[i] == JF || op[i] == JT || op[i] == JMP) && arg[i] != null && arg[i] instanceof Number) {
466 sb.append(" jump to ").append(i+((Number) arg[i]).intValue());
467 } else if(op[i] == TRY) {
468 int[] jmps = (int[]) arg[i];
469 sb.append(" catch: ").append(jmps[0] < 0 ? "No catch block" : ""+(i+jmps[0]));
470 sb.append(" finally: ").append(jmps[1] < 0 ? "No finally block" : ""+(i+jmps[1]));
474 return sb.toString();
477 // Exception Stuff ////////////////////////////////////////////////////////////////
479 static class EvaluatorException extends RuntimeException { public EvaluatorException(String s) { super(s); } }
480 EvaluatorException ee(String s) { throw new EvaluatorException(sourceName + ":" + JS.Thread.currentJSThread().getLine() + " " + s); }
481 JS.Exn je(String s) { throw new JS.Exn(sourceName + ":" + JS.Thread.currentJSThread().getLine() + " " + s); }
484 // FunctionScope /////////////////////////////////////////////////////////////////
486 private static class FunctionScope extends JS.Scope {
488 public FunctionScope(String sourceName, Scope parentScope) { super(parentScope); this.sourceName = sourceName; }
489 public String getSourceName() { return sourceName; }
493 // Markers //////////////////////////////////////////////////////////////////////
495 public static class CallMarker { public CallMarker() { } }
496 private static CallMarker callMarker = new CallMarker();
498 public static class CatchMarker { public CatchMarker() { } }
499 private static CatchMarker catchMarker = new CatchMarker();
501 public static class LoopMarker {
504 public JS.Scope scope;
505 public LoopMarker(int location, String label, JS.Scope scope) {
506 this.location = location;
511 public static class TryMarker {
513 public int finallyLoc;
514 public JS.Scope scope;
515 public TryMarker(int catchLoc, int finallyLoc, JS.Scope scope) {
516 this.catchLoc = catchLoc;
517 this.finallyLoc = finallyLoc;
521 public static class FinallyData {
524 public FinallyData(int op, Object arg) { this.op = op; this.arg = arg; }
525 public FinallyData(int op) { this(op,null); }
529 /** this class exists solely to work around a GCJ bug */
530 abstract class JSCallable extends JS.Callable {
531 public abstract Object call(JS.Array args) throws JS.Exn;