this.pausecount = pauseable ? 0 : -1;
this.scope = new JSScope(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");
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: {
- int depth = (arg == null ? 1 : JS.toInt((JS)arg));
- JS save = stack.elementAt(stack.size() - 1);
- for(int i=stack.size() - 1; i > stack.size() - 1 - depth; i--)
- stack.setElementAt(stack.elementAt(i-1), i);
- stack.setElementAt(save, stack.size() - depth - 1);
- 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");
- 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;
case PUSHKEYS: {
JS o = stack.peek();
- Enumeration e = o.keys();
- JSArray a = new JSArray();
- // FEATURE: Take advantage of the Enumeration, don't create a JSArray
- while(e.hasMoreElements()) a.addElement((JS)e.nextElement());
- stack.push(a);
+ stack.push(o == null ? null : o.keys());
break;
}
case BREAK:
case CONTINUE:
- while(stack.size() > 0) {
+ while(!stack.empty()) {
JS o = stack.pop();
if (o instanceof CallMarker) je("break or continue not within a loop");
if (o instanceof TryMarker) {
case RETURN: {
JS retval = stack.pop();
- while(stack.size() > 0) {
+ while(!stack.empty()) {
Object o = stack.pop();
if (o instanceof TryMarker) {
if(((TryMarker)o).finallyLoc < 0) continue;
pc = ((TryMarker)o).finallyLoc - 1;
continue OUTER;
} else if (o instanceof CallMarker) {
+ boolean didTrapPut = false;
if (o instanceof TrapMarker) { // handles return component of a read trap
TrapMarker tm = (TrapMarker) o;
- boolean cascade = tm.t.writeTrap() && !tm.cascadeHappened && !JS.toBoolean(retval);
+ boolean cascade = tm.t.isWriteTrap() && !tm.cascadeHappened && !JS.toBoolean(retval);
if(cascade) {
- Trap t = tm.t.next;
- while(t != null && t.readTrap()) t = t.next;
+ Trap t = tm.t.nextWriteTrap();
+ 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) {
- tm.t = t;
- stack.push(tm);
- stack.push(new JSArgs(tm.val,t.f));
- f = t.f;
- scope = new JSScope(f.parentScope);
- pc = -1;
+ tm.t = t; // we reuse the old trap marker
+ setupTrap(t,tm.val,tm);
+ pc--; // we increment it on the next iter
continue OUTER;
} else {
- tm.trapee.put(tm.key,tm.val);
+ didTrapPut = true;
+ if(!tm.pauseOnPut) tm.t.target.put(tm.t.key,tm.val);
}
}
}
- scope = ((CallMarker)o).scope;
- pc = ((CallMarker)o).pc - 1;
- f = (JSFunction)((CallMarker)o).f;
- stack.push(retval);
- if (pausecount > initialPauseCount) { pc++; return null; } // we were paused
- if(f == null) return retval;
+ CallMarker cm = (CallMarker) o;
+ scope = cm.scope;
+ pc = cm.pc - 1;
+ f = cm.f;
+ 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;
}
}
Trap t = null;
TrapMarker tm = null;
if(target instanceof JSScope && key.jsequals(CASCADE)) {
- Object o=null;
- int i;
- for(i=stack.size()-1;i>=0;i--) if((o = stack.elementAt(i)) instanceof CallMarker) break;
- if(i==0) throw new Error("didn't find a call marker while doing cascade");
+ CallMarker o = stack.findCall();
if(o instanceof TrapMarker) {
tm = (TrapMarker) o;
- target = tm.trapee;
- key = tm.key;
+ target = tm.t.target;
+ key = tm.t.key;
tm.cascadeHappened = true;
t = tm.t;
- if(t.readTrap()) throw new JSExn("can't do a write cascade in a read trap");
- t = t.next;
- while(t != null && t.readTrap()) t = t.next;
+ if(t.isReadTrap()) throw new JSExn("can't do a write cascade in a read trap");
+ t = t.nextWriteTrap();
}
}
- if(tm == null) { // didn't find a trap marker, try to find a trap
- t = target instanceof JSScope ? t = ((JSScope)target).top().getTrap(key) : ((JS)target).getTrap(key);
- while(t != null && t.readTrap()) t = t.next;
+ if(tm == null) { // not cascading
+ t = target instanceof JSScope ? t = ((JSScope)target).top().getTrap(key) : 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);
+ if(t != null) t = t.writeTrap();
+ }
+
stack.push(val);
if(t != null) {
- stack.push(new TrapMarker(this,t,target,key,val));
- stack.push(new JSArgs(t.f));
- f = t.f;
- scope = new TrapScope(f.parentScope,target,f,key);
- pc = -1;
+ setupTrap(t,val,new TrapMarker(this,t,val, tm != null && tm.pauseOnPut));
+ pc--; // we increment later
break;
} else {
+ if (tm != null && tm.pauseOnPut) { pc++; return val; }
target.put(key,val);
if (pausecount > initialPauseCount) { pc++; return null; } // we were paused
break;
Trap t = null;
TrapMarker tm = null;
if(target instanceof JSScope && key.jsequals(CASCADE)) {
- JS o=null;
- int i;
- for(i=stack.size()-1;i>=0;i--) if((o = stack.elementAt(i)) instanceof CallMarker) break;
- if(i==0) throw new Error("didn't find a call marker while doing cascade");
+ CallMarker o = stack.findCall();
if(o instanceof TrapMarker) {
tm = (TrapMarker) o;
- target = tm.trapee;
- key = tm.key;
+ target = tm.t.target;
+ key = tm.t.key;
t = tm.t;
- if(t.writeTrap()) throw new JSExn("can't do a read cascade in a write trap");
- t = t.next;
- while(t != null && t.writeTrap()) t = t.next;
- if(t != null) tm.cascadeHappened = true;
+ if(t.isWriteTrap()) throw new JSExn("can't do a read cascade in a write trap");
+ t = t.nextReadTrap();
}
}
- if(tm == null) { // didn't find a trap marker, try to find a trap
+ if(tm == null) { // not cascading
t = target instanceof JSScope ? t = ((JSScope)target).top().getTrap(key) : ((JS)target).getTrap(key);
- while(t != null && t.writeTrap()) t = t.next;
+ 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) t = t.readTrap();
}
if(t != null) {
- stack.push(new TrapMarker(this,t,(JS)target,key,null));
- stack.push(new JSArgs(t.f));
- f = t.f;
- scope = new TrapScope(f.parentScope,target,f,key);
- pc = -1;
+ setupTrap(t,null,new TrapMarker(this,t,null));
+ pc--; // we increment later
break;
} else {
ret = target.get(key);
}
case THROW:
- throw new JSExn(stack.pop(), stack, f, pc, scope);
+ throw new JSExn(stack.pop(), this);
/* FIXME GRAMMAR
case MAKE_GRAMMAR: {
if a handler is not found the exception is thrown
*/
void catchException(JSExn e) throws JSExn {
- while(stack.size() > 0) {
+ while(!stack.empty()) {
JS o = stack.pop();
if (o instanceof CatchMarker || o instanceof TryMarker) {
boolean inCatch = o instanceof CatchMarker;
throw e;
}
+ 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));
+ f = t.f;
+ scope = new TrapScope(t.f.parentScope,t);
+ pc = 0;
+ }
// Markers //////////////////////////////////////////////////////////////////////
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;
- final JS trapee;
- final JS key;
- final JS val;
+ JS val;
boolean cascadeHappened;
- public TrapMarker(Interpreter cx, Trap t, JS trapee, 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.trapee = trapee;
- this.key = key;
this.val = val;
+ this.pauseOnPut = pauseOnPut;
}
}
}
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;
+ private Trap t;
+ public TrapScope(JSScope parent, Trap t) {
+ super(parent); this.t = t;
}
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
- }
+ //#jswitch(key)
+ case "trapee": return t.target;
+ case "callee": return t.f;
+ case "trapname": return t.key;
+ //#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
private static final int MAX_STACK_SIZE = 512;
private JS[] stack = new JS[64];
private int sp = 0;
- public final void push(JS o) throws JSExn {
- if(sp == stack.length) grow();
- stack[sp++] = o;
- }
- public final JS peek() {
- if(sp == 0) throw new RuntimeException("Stack underflow");
- return stack[sp-1];
+
+ boolean empty() { return sp == 0; }
+ void push(JS o) throws JSExn { if(sp == stack.length) grow(); stack[sp++] = o; }
+ JS peek() { if(sp == 0) throw new RuntimeException("Stack underflow"); return stack[sp-1]; }
+ final JS pop() { if(sp == 0) throw new RuntimeException("Stack underflow"); return stack[--sp]; }
+ void swap() throws JSExn {
+ if(sp < 2) throw new JSExn("stack overflow");
+ JS tmp = stack[sp-2];
+ stack[sp-2] = stack[sp-1];
+ stack[sp-1] = tmp;
}
- public final JS pop() {
- if(sp == 0) throw new RuntimeException("Stack underflow");
- return stack[--sp];
+ CallMarker findCall() {
+ for(int i=sp-1;i>=0;i--) if(stack[i] instanceof CallMarker) return (CallMarker) stack[i];
+ return null;
}
- private void grow() throws JSExn {
+ void grow() throws JSExn {
if(stack.length >= MAX_STACK_SIZE) throw new JSExn("Stack overflow");
JS[] stack2 = new JS[stack.length * 2];
System.arraycopy(stack,0,stack2,0,stack.length);
- }
- public int size() { return sp; }
- public JS elementAt(int i) { return stack[i]; }
+ }
- // FIXME: Eliminate all uses of SWAP n>1 so we don't need this
- public void setElementAt(JS o, int i) { stack[i] = o; }
+ void backtrace(JSExn e) {
+ for(int i=sp-1;i>=0;i--) {
+ if (stack[i] instanceof CallMarker) {
+ CallMarker cm = (CallMarker)stack[i];
+ 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).t.key) + ")";
+ e.addBacktrace(s);
+ }
+ }
+ }
}
}
projects / org.ibex.core.git / blobdiff