/** Encapsulates a single JS interpreter (ie call stack) */
class Interpreter implements ByteCodes, Tokens {
- private static final JS CASCADE = JSString.intern("cascade");
-
// Thread-Interpreter Mapping /////////////////////////////////////////////////////////////////////////
static Interpreter current() { return (Interpreter)threadToInterpreter.get(Thread.currentThread()); }
Interpreter(JSFunction f, boolean pauseable, JSArgs args) {
this.f = f;
this.pausecount = pauseable ? 0 : -1;
- this.scope = new JSScope(f.parentScope);
+ this.scope = f.parentScope;
try {
- stack.push(new CallMarker()); // the "root function returned" marker -- f==null
+ stack.push(new CallMarker(null)); // the "root function returned" marker -- f==null
stack.push(args);
} catch(JSExn e) {
throw new Error("should never happen");
}
}
+ Interpreter(Trap t, JS val, boolean pauseOnPut) {
+ this.pausecount = -1;
+ try {
+ setupTrap(t,val,new TrapMarker(null,t,val,pauseOnPut));
+ } catch(JSExn e) {
+ throw new Error("should never happen");
+ }
+ }
+
/** this is the only synchronization point we need in order to be threadsafe */
synchronized JS resume() throws JSExn {
if(f == null) throw new RuntimeException("function already finished");
+ if(scope == null) throw new RuntimeException("scope is null");
Thread t = Thread.currentThread();
Interpreter old = (Interpreter)threadToInterpreter.get(t);
threadToInterpreter.put(t, this);
case LITERAL: stack.push((JS)arg); break;
case OBJECT: stack.push(new JS.O()); break;
case ARRAY: stack.push(new JSArray(JS.toInt((JS)arg))); break;
- case DECLARE: scope.declare((JS)(arg==null ? stack.peek() : arg)); if(arg != null) stack.push((JS)arg); break;
- case TOPSCOPE: stack.push(scope); break;
+ //case DECLARE: scope.declare((JS)(arg==null ? stack.peek() : arg)); if(arg != null) stack.push((JS)arg); break;
case JT: if (JS.toBoolean(stack.pop())) pc += JS.toInt((JS)arg) - 1; break;
case JF: if (!JS.toBoolean(stack.pop())) pc += JS.toInt((JS)arg) - 1; break;
case JMP: pc += JS.toInt((JS)arg) - 1; break;
case POP: stack.pop(); break;
case SWAP: stack.swap(); break;
case DUP: stack.push(stack.peek()); break;
- case NEWSCOPE: scope = new JSScope(scope); break;
- case OLDSCOPE: scope = scope.getParentScope(); break;
- case ASSERT: {
- JS o = stack.pop();
- if (JS.checkAssertions && !JS.toBoolean(o))
- throw je("ibex.assertion.failed");
+ case NEWSCOPE: {
+ int n = JS.toInt((JS)arg);
+ scope = new JSScope(scope,(n>>>16)&0xffff,(n>>>0)&0xffff);
break;
}
+ case OLDSCOPE: scope = scope.parent; break;
+ case GLOBALSCOPE: stack.push(scope.getGlobal()); break;
+ case SCOPEGET: stack.push(scope.get((JS)arg)); break;
+ case SCOPEPUT: scope.put((JS)arg,stack.peek()); break;
+ case ASSERT: if (!JS.toBoolean(stack.pop())) throw je("ibex.assertion.failed"); break;
case BITNOT: stack.push(JS.N(~JS.toLong(stack.pop()))); break;
case BANG: stack.push(JS.B(!JS.toBoolean(stack.pop()))); break;
case NEWFUNCTION: stack.push(((JSFunction)arg)._cloneWithNewParentScope(scope)); break;
pc = ((TryMarker)o).finallyLoc - 1;
continue OUTER;
} else if (o instanceof CallMarker) {
- if (o instanceof TrapMarker) { // handles return component of a read trap
+ boolean didTrapPut = false;
+ if (o instanceof TrapMarker) { // handles return component of a write trap
TrapMarker tm = (TrapMarker) o;
boolean cascade = tm.t.isWriteTrap() && !tm.cascadeHappened && !JS.toBoolean(retval);
if(cascade) {
Trap t = tm.t.nextWriteTrap();
- if(t == null && tm.target instanceof JS.Clone) {
- tm.target = ((JS.Clone)tm.target).clonee;
- t = tm.target.getTrap(tm.key);
+ if(t == null && tm.t.target instanceof JS.Clone) {
+ t = ((JS.Clone)tm.t.target).clonee.getTrap(tm.t.key);
if(t != null) t = t.writeTrap();
}
if(t != null) {
pc--; // we increment it on the next iter
continue OUTER;
} else {
- tm.target.put(tm.key,tm.val);
+ didTrapPut = true;
+ if(!tm.pauseOnPut) tm.t.target.put(tm.t.key,tm.val);
}
}
}
scope = cm.scope;
pc = cm.pc - 1;
f = cm.f;
- stack.push(retval);
- if (pausecount > initialPauseCount) { pc++; return null; } // we were paused
- if(f == null) return retval;
+ if (didTrapPut) {
+ if (((TrapMarker)cm).pauseOnPut) { pc++; return ((TrapMarker)cm).val; }
+ if (pausecount > initialPauseCount) { pc++; return null; } // we were paused
+ } else {
+ stack.push(retval);
+ }
+ if (f == null) return retval;
continue OUTER;
}
}
throw new Error("error: RETURN invoked but couldn't find a CallMarker!");
}
-
+
+ case CASCADE: {
+ boolean write = JS.toBoolean((JS)arg);
+ JS val = write ? stack.pop() : null;
+ CallMarker o = stack.findCall();
+ if(!(o instanceof TrapMarker)) throw new JSExn("tried to CASCADE while not in a trap");
+ TrapMarker tm = (TrapMarker) o;
+ JS key = tm.t.key;
+ JS target = tm.t.target;
+ if(tm.t.isWriteTrap() != write) throw new JSExn("tried to do a " + (write?"write":"read") + " cascade in a " + (write?"read":"write") + " trap");
+ Trap t = write ? tm.t.nextWriteTrap() : tm.t.nextReadTrap();
+ // FIXME: Doesn't handle multiple levels of clone's (probably can just make this a while loop)
+ if(t == null && target instanceof JS.Clone) {
+ target = ((JS.Clone)target).clonee;
+ t = target.getTrap(key);
+ if(t != null) t = write ? t.writeTrap() : t.readTrap();
+ }
+ if(write) {
+ tm.cascadeHappened = true;
+ stack.push(val);
+ }
+ if(t != null) {
+ setupTrap(t,val,new TrapMarker(this,t,val,tm.pauseOnPut));
+ pc--; // we increment later
+ } else {
+ if(write) {
+ if (tm.pauseOnPut) { pc++; return val; }
+ target.put(key,val);
+ } else {
+ JS ret = target.get(key);
+ if (ret == JS.METHOD) ret = new Stub(target, key);
+ stack.push(ret);
+ }
+ if (pausecount > initialPauseCount) { pc++; return null; } // we were paused
+ }
+ break;
+ }
+
case PUT: {
JS val = stack.pop();
JS key = stack.pop();
if (target == null) throw je("tried to put " + JS.debugToString(val) + " to the " + JS.debugToString(key) + " property on the null value");
if (key == null) throw je("tried to assign \"" + JS.debugToString(val) + "\" to the null key");
- Trap t = null;
- TrapMarker tm = null;
- if(target instanceof JSScope && key.jsequals(CASCADE)) {
- CallMarker o = stack.findCall();
- if(o instanceof TrapMarker) {
- tm = (TrapMarker) o;
- target = tm.target;
- key = tm.key;
- tm.cascadeHappened = true;
- t = tm.t;
- if(t.isReadTrap()) throw new JSExn("can't do a write cascade in a read trap");
- t = t.nextWriteTrap();
- }
- }
- if(tm == null) { // not cascading
- t = target instanceof JSScope ? t = ((JSScope)target).top().getTrap(key) : target.getTrap(key);
- if(t != null) t = t.writeTrap();
- }
+ Trap t = target.getTrap(key);
+ if(t != null) t = t.writeTrap();
+
if(t == null && target instanceof JS.Clone) {
target = ((JS.Clone)target).clonee;
t = target.getTrap(key);
stack.push(val);
if(t != null) {
- setupTrap(t,val,new TrapMarker(this,t,target,key,val));
+ setupTrap(t,val,new TrapMarker(this,t,val));
pc--; // we increment later
- break;
} else {
target.put(key,val);
if (pausecount > initialPauseCount) { pc++; return null; } // we were paused
- break;
}
+ break;
}
case GET:
stack.push(key);
}
JS ret = null;
- if (key == null) throw je("tried to get the null key from " + target);
- if (target == null) throw je("tried to get property \"" + key + "\" from the null object");
+ if (key == null) throw je("tried to get the null key from " + JS.debugToString(target));
+ if (target == null) throw je("tried to get property \"" + JS.debugToString(key) + "\" from the null object");
+
+ Trap t = target.getTrap(key);
+ if(t != null) t = t.readTrap();
- Trap t = null;
- TrapMarker tm = null;
- if(target instanceof JSScope && key.jsequals(CASCADE)) {
- CallMarker o = stack.findCall();
- if(o instanceof TrapMarker) {
- tm = (TrapMarker) o;
- target = tm.target;
- key = tm.key;
- t = tm.t;
- if(t.isWriteTrap()) throw new JSExn("can't do a read cascade in a write trap");
- t = t.nextReadTrap();
- }
- }
- if(tm == null) { // not cascading
- t = target instanceof JSScope ? t = ((JSScope)target).top().getTrap(key) : ((JS)target).getTrap(key);
- if(t != null) t = t.readTrap();
- }
if(t == null && target instanceof JS.Clone) {
target = ((JS.Clone)target).clonee;
t = target.getTrap(key);
}
if(t != null) {
- setupTrap(t,null,new TrapMarker(this,t,target,key,null));
+ setupTrap(t,null,new TrapMarker(this,t,null));
pc--; // we increment later
- break;
} else {
ret = target.get(key);
if (pausecount > initialPauseCount) { pc++; return null; } // we were paused
if (ret == JS.METHOD) ret = new Stub(target, key);
stack.push(ret);
- break;
}
+ break;
}
case CALL: case CALLMETHOD: {
stack.push(new CallMarker(this));
stack.push(new JSArgs(a0,a1,a2,rest,numArgs,object));
f = (JSFunction)object;
- scope = new JSScope(f.parentScope);
+ scope = f.parentScope;
pc = -1;
break;
} else {
JS js = stack.peek();
// A trap addition/removal
if(!(val instanceof JSFunction)) throw new JSExn("tried to add/remove a non-function trap");
- if(js instanceof JSScope) {
- JSScope s = (JSScope) js;
- while(s.getParentScope() != null) {
- if(s.has(key)) throw new JSExn("cannot trap a variable that isn't at the top level scope");
- s = s.getParentScope();
- }
- js = s;
- }
if(op == ADD_TRAP) js.addTrap(key, (JSFunction)val);
else js.delTrap(key, (JSFunction)val);
break;
void setupTrap(Trap t, JS val, CallMarker cm) throws JSExn {
stack.push(cm);
- stack.push(t.isWriteTrap() ? new JSArgs(val,t.f) : new JSArgs(t.f));
+ stack.push(new TrapArgs(t,val));
f = t.f;
- scope = new TrapScope(t.f.parentScope,t.target,t.f,t.key);
+ scope = f.parentScope;
pc = 0;
}
final int pc;
final JSScope scope;
final JSFunction f;
- public CallMarker(Interpreter cx) { pc = cx.pc + 1; scope = cx.scope; f = cx.f; }
- public CallMarker() { pc = -1; scope = null; f = null; }
+ public CallMarker(Interpreter cx) {
+ pc = cx == null ? -1 : cx.pc + 1;
+ scope = cx == null ? null : cx.scope;
+ f = cx == null ? null : cx.f;
+ }
}
static class TrapMarker extends CallMarker {
Trap t;
- JS target;
- final JS key;
- final JS val;
+ JS val;
boolean cascadeHappened;
- public TrapMarker(Interpreter cx, Trap t, JS target, JS key, JS val) {
+ final boolean pauseOnPut;
+ public TrapMarker(Interpreter cx, Trap t, JS val) { this(cx,t,val,false); }
+ public TrapMarker(Interpreter cx, Trap t, JS val, boolean pauseOnPut) {
super(cx);
this.t = t;
- this.target = target;
- this.key = key;
this.val = val;
+ this.pauseOnPut = pauseOnPut;
}
}
public FinallyData(JSExn exn) { this.exn = exn; this.op = -1; this.arg = null; } // Just throw this exn
}
- static class TrapScope extends JSScope {
- JS trapee;
- JS callee;
- JS trapname;
- public TrapScope(JSScope parent, JS trapee, JS callee, JS trapname) {
- super(parent); this.trapee = trapee; this.callee = callee; this.trapname = trapname;
- }
+ static class TrapArgs extends JS {
+ private Trap t;
+ private JS val;
+ public TrapArgs(Trap t, JS val) { this.t = t; this.val = val; }
public JS get(JS key) throws JSExn {
- if(JS.isString(key)) {
- //#switch(JS.toString(key))
- case "trapee": return trapee;
- case "callee": return callee;
- case "trapname": return trapname;
- //#end
- }
+ if(JS.isInt(key) && JS.toInt(key) == 0) return val;
+ //#jswitch(key)
+ case "trapee": return t.target;
+ case "callee": return t.f;
+ case "trapname": return t.key;
+ case "length": return t.isWriteTrap() ? ONE : ZERO;
+ //#end
return super.get(key);
}
}
default: return n>= 0 && n < nargs ? rest[n-3] : null;
}
}
- //#switch(JS.toString(key))
+ //#jswitch(key)
case "callee": return callee;
case "length": return JS.N(nargs);
//#end
if(cm.f == null) break;
String s = cm.f.sourceName + ":" + cm.f.line[cm.pc-1];
if(cm instanceof Interpreter.TrapMarker)
- s += " (trap on " + JS.debugToString(((Interpreter.TrapMarker)cm).key) + ")";
+ s += " (trap on " + JS.debugToString(((Interpreter.TrapMarker)cm).t.key) + ")";
e.addBacktrace(s);
}
}
projects / org.ibex.core.git / blobdiff