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);
44 protected CompiledFunctionImpl(String sourceName, int firstLine, Reader sourceCode, JS.Scope parentScope) throws IOException {
45 this.sourceName = sourceName;
46 this.firstLine = firstLine;
47 this.parentScope = parentScope;
48 if (sourceCode == null) return;
49 Parser p = new Parser(sourceCode, sourceName, firstLine);
52 p.parseStatement(this, null);
53 if (s == size()) break;
55 add(-1, LITERAL, null);
59 public Object call(JS.Array args) throws JS.Exn { return call(args, new FunctionScope(sourceName, parentScope)); }
60 public Object call(JS.Array args, JS.Scope scope) throws JS.Exn {
61 JS.Thread cx = JS.Thread.fromJavaThread(java.lang.Thread.currentThread());
62 CompiledFunction saved = cx.currentCompiledFunction;
64 cx.currentCompiledFunction = (CompiledFunction)this;
65 int size = cx.stack.size();
66 cx.stack.push(new CallMarker());
69 Object ret = cx.stack.pop();
70 // FIXME: if we catch an exception in Java, JS won't notice and the stack will be messed up
71 if (cx.stack.size() > size)
72 // this should never happen
73 throw new Error("ERROR: stack grew by " + (cx.stack.size() - size) + " elements during call");
76 cx.currentCompiledFunction = saved;
81 // Adding and Altering Bytecodes ///////////////////////////////////////////////////
83 int get(int pos) { return op[pos]; }
84 Object getArg(int pos) { return arg[pos]; }
85 void set(int pos, int op_, Object arg_) { op[pos] = op_; arg[pos] = arg_; }
86 void set(int pos, Object arg_) { arg[pos] = arg_; }
87 int pop() { size--; arg[size] = null; return op[size]; }
88 void paste(CompiledFunctionImpl other) { for(int i=0; i<other.size; i++) add(other.line[i], other.op[i], other.arg[i]); }
89 CompiledFunctionImpl add(int line, int op_) { return add(line, op_, null); }
90 CompiledFunctionImpl add(int line, int op_, Object arg_) {
91 if (size == op.length - 1) {
92 int[] line2 = new int[op.length * 2]; System.arraycopy(this.line, 0, line2, 0, op.length); this.line = line2;
93 Object[] arg2 = new Object[op.length * 2]; System.arraycopy(arg, 0, arg2, 0, arg.length); arg = arg2;
94 int[] op2 = new int[op.length * 2]; System.arraycopy(op, 0, op2, 0, op.length); op = op2;
96 this.line[size] = line;
103 public int getLine(int pc) {
104 if(pc < 0 || pc >= size) return -1;
109 // Invoking the Bytecode ///////////////////////////////////////////////////////
111 void eval(JS.Scope s) {
112 final JS.Thread cx = JS.Thread.fromJavaThread(java.lang.Thread.currentThread());
113 final Vec t = cx.stack;
116 OUTER: for(pc=0; pc<size; pc++) {
120 Object curArg = arg[pc];
121 if(curOP == FINALLY_DONE) {
122 FinallyData fd = (FinallyData) t.pop();
123 if(fd == null) continue OUTER; // NOP
128 case LITERAL: t.push(arg[pc]); break;
129 case OBJECT: t.push(new JS.Obj()); break;
130 case ARRAY: t.push(new JS.Array(JS.toNumber(arg[pc]).intValue())); break;
131 case DECLARE: s.declare((String)(arg[pc]==null ? t.peek() : arg[pc])); if(arg[pc] != null) t.push(arg[pc]); break;
132 case TOPSCOPE: t.push(s); break;
133 case JT: if (JS.toBoolean(t.pop())) pc += JS.toNumber(arg[pc]).intValue() - 1; break;
134 case JF: if (!JS.toBoolean(t.pop())) pc += JS.toNumber(arg[pc]).intValue() - 1; break;
135 case JMP: pc += JS.toNumber(arg[pc]).intValue() - 1; break;
136 case POP: t.pop(); break;
137 case SWAP: { Object o1 = t.pop(); Object o2 = t.pop(); t.push(o1); t.push(o2); break; }
138 case DUP: t.push(t.peek()); break;
139 case NEWSCOPE: s = new JS.Scope(s); break;
140 case OLDSCOPE: s = s.getParentScope(); break;
141 case ASSERT: if (!JS.toBoolean(t.pop())) throw je("assertion failed"); break;
142 case BITNOT: t.push(new Long(~JS.toLong(t.pop()))); break;
143 case BANG: t.push(new Boolean(!JS.toBoolean(t.pop()))); break;
147 if (o == null) t.push(null);
148 else if (o instanceof JS) t.push(((JS)o).typeName());
149 else if (o instanceof String) t.push("string");
150 else if (o instanceof Number) t.push("number");
151 else if (o instanceof Boolean) t.push("boolean");
152 else t.push("unknown");
158 t.push(((CompiledFunctionImpl)arg[pc]).cloneWithNewParentScope(s));
159 } catch (IOException e) {
160 throw new Error("this should never happen");
167 Object[] keys = ((JS)o).keys();
168 JS.Array a = new JS.Array();
169 a.setSize(keys.length);
170 for(int j=0; j<keys.length; j++) a.setElementAt(keys[j], j);
177 t.push(new LoopMarker(pc, pc > 0 && op[pc - 1] == LABEL ? (String)arg[pc - 1] : (String)null,s));
178 t.push(Boolean.TRUE);
184 while(t.size() > 0) {
186 if (o instanceof CallMarker) ee("break or continue not within a loop");
187 if (o instanceof TryMarker) {
188 if(((TryMarker)o).finallyLoc < 0) continue; // no finally block, keep going
189 t.push(new FinallyData(curOP, curArg));
190 s = ((TryMarker)o).scope;
191 pc = ((TryMarker)o).finallyLoc - 1;
194 if (o instanceof LoopMarker) {
195 if (curArg == null || curArg.equals(((LoopMarker)o).label)) {
196 int loopInstructionLocation = ((LoopMarker)o).location;
197 int endOfLoop = ((Integer)arg[loopInstructionLocation]).intValue() + loopInstructionLocation;
198 s = ((LoopMarker)o).scope;
199 if (curOP == CONTINUE) { t.push(o); t.push(Boolean.FALSE); }
200 pc = curOP == BREAK ? endOfLoop - 1 : loopInstructionLocation;
205 throw new Error("CONTINUE/BREAK invoked but couldn't find a LoopMarker at " + sourceName + ":" + getLine(pc));
208 int[] jmps = (int[]) arg[pc];
209 // jmps[0] is how far away the catch block is, jmps[1] is how far away the finally block is
210 // each can be < 0 if the specified block does not exist
211 t.push(new TryMarker(jmps[0] < 0 ? -1 : pc + jmps[0], jmps[1] < 0 ? -1 : pc + jmps[1],s));
216 Object retval = t.pop();
217 while(t.size() > 0) {
219 if (o instanceof TryMarker) {
220 if(((TryMarker)o).finallyLoc < 0) continue;
222 t.push(new FinallyData(RETURN));
223 s = ((TryMarker)o).scope;
224 pc = ((TryMarker)o).finallyLoc - 1;
227 if (o instanceof CallMarker) {
232 throw new Error("error: RETURN invoked but couldn't find a CallMarker!");
236 Object val = t.pop();
237 Object key = t.pop();
238 Object target = t.peek();
240 throw je("tried to put a value to the " + key + " property on the null value");
241 if (!(target instanceof JS))
242 throw je("tried to put a value to the " + key + " property on a " + target.getClass().getName());
244 throw je("tried to assign \"" + (val==null?"(null)":val.toString()) + "\" to the null key");
245 ((JS)target).put(key, val);
254 v = arg[pc] == null ? t.pop() : arg[pc];
262 if (o == null) throw je("tried to get property \"" + v + "\" from the null value");
263 if (v == null) throw je("tried to get the null key from " + o);
264 if (o instanceof String || o instanceof Number || o instanceof Boolean)
265 ret = Internal.getFromPrimitive(o,v);
266 else if (o instanceof JS)
267 ret = ((JS)o).get(v);
269 throw je("tried to get property " + v + " from a " + o.getClass().getName());
277 JS.Array arguments = new JS.Array();
278 int numArgs = JS.toNumber(arg[pc]).intValue();
279 arguments.setSize(numArgs);
280 for(int j=numArgs - 1; j >= 0; j--) arguments.setElementAt(t.pop(), j);
282 if(o == null) throw je("attempted to call null");
285 if(op[pc] == CALLMETHOD) {
288 if(o instanceof String || o instanceof Number || o instanceof Boolean)
289 ret = Internal.callMethodOnPrimitive(o,method,arguments);
290 else if(o instanceof JS)
291 ret = ((JS)o).callMethod(method,arguments,false);
293 throw new JS.Exn("Tried to call a method on an object that isn't a JS object");
295 ret = ((JS.Callable)o).call(arguments);
303 // fall through if exception was thrown
305 Object exn = t.pop();
306 while(t.size() > 0) {
308 if (o instanceof CatchMarker || o instanceof TryMarker) {
309 boolean inCatch = o instanceof CatchMarker;
312 if(((TryMarker)o).finallyLoc < 0) continue; // no finally block, keep going
314 if(!inCatch && ((TryMarker)o).catchLoc >= 0) {
315 // run the catch block, this will implicitly run the finally block, if it exists
318 t.push((exn instanceof JS.Exn) ? ((JS.Exn)exn).getObject() : exn);
319 s = ((TryMarker)o).scope;
320 pc = ((TryMarker)o).catchLoc - 1;
324 t.push(new FinallyData(THROW));
325 s = ((TryMarker)o).scope;
326 pc = ((TryMarker)o).finallyLoc - 1;
330 // no handler found within this func
331 if(o instanceof CallMarker) {
332 if(exn instanceof JS.Exn)
335 throw new JS.Exn(exn);
338 throw new Error("error: THROW invoked but couldn't find a Try or Call Marker!");
341 case INC: case DEC: {
342 boolean isPrefix = JS.toBoolean(arg[pc]);
343 Object key = t.pop();
344 JS obj = (JS)t.pop();
345 Number num = JS.toNumber(obj.get(key));
346 Number val = new Double(op[pc] == INC ? num.doubleValue() + 1.0 : num.doubleValue() - 1.0);
348 t.push(isPrefix ? val : num);
353 Object right = t.pop();
354 Object left = t.pop();
360 if (l instanceof String || r instanceof String) {
361 if (l == null) l = "null";
362 if (r == null) r = "null";
363 if (l instanceof Number && ((Number)l).doubleValue() == ((Number)l).longValue())
364 l = new Long(((Number)l).longValue());
365 if (r instanceof Number && ((Number)r).doubleValue() == ((Number)r).longValue())
366 r = new Long(((Number)r).longValue());
367 t.push(l.toString() + r.toString()); break;
369 t.push(new Double(JS.toDouble(l) + JS.toDouble(r))); break;
372 case BITOR: t.push(new Long(JS.toLong(left) | JS.toLong(right))); break;
373 case BITXOR: t.push(new Long(JS.toLong(left) ^ JS.toLong(right))); break;
374 case BITAND: t.push(new Long(JS.toLong(left) & JS.toLong(right))); break;
376 case SUB: t.push(new Double(JS.toDouble(left) - JS.toDouble(right))); break;
377 case MUL: t.push(new Double(JS.toDouble(left) * JS.toDouble(right))); break;
378 case DIV: t.push(new Double(JS.toDouble(left) / JS.toDouble(right))); break;
379 case MOD: t.push(new Double(JS.toDouble(left) % JS.toDouble(right))); break;
381 case LSH: t.push(new Long(JS.toLong(left) << JS.toLong(right))); break;
382 case RSH: t.push(new Long(JS.toLong(left) >> JS.toLong(right))); break;
383 case URSH: t.push(new Long(JS.toLong(left) >>> JS.toLong(right))); break;
385 case LT: case LE: case GT: case GE: {
386 if (left == null) left = new Integer(0);
387 if (right == null) right = new Integer(0);
389 if (left instanceof String || right instanceof String) {
390 result = left.toString().compareTo(right.toString());
392 result = (int)java.lang.Math.ceil(JS.toDouble(left) - JS.toDouble(right));
394 t.push(new Boolean((op[pc] == LT && result < 0) || (op[pc] == LE && result <= 0) ||
395 (op[pc] == GT && result > 0) || (op[pc] == GE && result >= 0)));
404 if (l == null) { Object tmp = r; r = l; l = tmp; }
405 if (l == null && r == null) ret = true;
406 else if (r == null) ret = false; // l != null, so its false
407 else if (l instanceof Boolean) ret = new Boolean(JS.toBoolean(r)).equals(l);
408 else if (l instanceof Number) ret = JS.toNumber(r).doubleValue() == JS.toNumber(l).doubleValue();
409 else if (l instanceof String) ret = r != null && l.equals(r.toString());
410 else ret = l.equals(r);
411 t.push(new Boolean(op[pc] == EQ ? ret : !ret)); break;
414 default: throw new Error("unknown opcode " + op[pc]);
418 // this should never happen, we will ALWAYS have a RETURN at the end of the func
419 throw new Error("Just fell out of CompiledFunction::eval() loop. Last PC was " + lastPC);
422 // Debugging //////////////////////////////////////////////////////////////////////
424 public String toString() {
425 StringBuffer sb = new StringBuffer(1024);
426 sb.append("\n" + sourceName + ": " + firstLine + "\n");
427 for (int i=0; i < size; i++) {
431 sb.append(bytecodeToString[-op[i]]);
433 sb.append(codeToString[op[i]]);
435 sb.append(arg[i] == null ? "(no arg)" : arg[i]);
436 if((op[i] == JF || op[i] == JT || op[i] == JMP) && arg[i] != null && arg[i] instanceof Number) {
437 sb.append(" jump to ").append(i+((Number) arg[i]).intValue());
438 } else if(op[i] == TRY) {
439 int[] jmps = (int[]) arg[i];
440 sb.append(" catch: ").append(jmps[0] < 0 ? "No catch block" : ""+(i+jmps[0]));
441 sb.append(" finally: ").append(jmps[1] < 0 ? "No finally block" : ""+(i+jmps[1]));
445 return sb.toString();
448 // Exception Stuff ////////////////////////////////////////////////////////////////
450 static class EvaluatorException extends RuntimeException { public EvaluatorException(String s) { super(s); } }
451 EvaluatorException ee(String s) { throw new EvaluatorException(sourceName + ":" + JS.Thread.currentJSThread().getLine() + " " + s); }
452 JS.Exn je(String s) { throw new JS.Exn(sourceName + ":" + JS.Thread.currentJSThread().getLine() + " " + s); }
455 // FunctionScope /////////////////////////////////////////////////////////////////
457 private class FunctionScope extends JS.Scope {
459 public FunctionScope(String sourceName, Scope parentScope) { super(parentScope); this.sourceName = sourceName; }
460 public String getSourceName() { return sourceName; }
464 // Markers //////////////////////////////////////////////////////////////////////
466 public static class CallMarker { public CallMarker() { } }
468 public static class CatchMarker { public CatchMarker() { } }
469 private static CatchMarker catchMarker = new CatchMarker();
471 public static class LoopMarker {
474 public JS.Scope scope;
475 public LoopMarker(int location, String label, JS.Scope scope) {
476 this.location = location;
481 public static class TryMarker {
483 public int finallyLoc;
484 public JS.Scope scope;
485 public TryMarker(int catchLoc, int finallyLoc, JS.Scope scope) {
486 this.catchLoc = catchLoc;
487 this.finallyLoc = finallyLoc;
491 public static class FinallyData {
494 public FinallyData(int op, Object arg) { this.op = op; this.arg = arg; }
495 public FinallyData(int op) { this(op,null); }
499 /** this class exists solely to work around a GCJ bug */
500 abstract class JSCallable extends JS.Callable {
501 public abstract Object call(JS.Array args) throws JS.Exn;