Terminate execution when there's only one frame left

context.js

@@ -134,7 +134,9 @@ Context.prototype.execute = function(stopFrame) {
         throw e;
       }
     }
-  } while (this.current() !== stopFrame);
+  } while (this.frames.length !== 1);
+
+  this.frames.pop();
 }
 
 Context.prototype.start = function(stopFrame) {
@@ -159,7 +161,10 @@ Context.prototype.start = function(stopFrame) {
     }
     Instrument.callPauseHooks(ctx.current());
 
-    if (ctx.current() === stopFrame) {
+    // If there's one frame left, we're back to
+    // the method that created the thread and
+    // we're done.
+    if (ctx.frames.length === 1) {
       ctx.kill();
       return;
     }

vm.js

@@ -1077,9 +1077,9 @@ VM.execute = function(ctx) {
             if (VM.DEBUG) {
                 VM.trace("return", ctx.thread.pid, frame.methodInfo);
             }
-            popFrame(0);
-            if (!frame.methodInfo)
+            if (ctx.frames.length == 1)
                 return;
+            popFrame(0);
             break;
         case 0xac: // ireturn
         case 0xae: // freturn
@@ -1087,18 +1087,18 @@ VM.execute = function(ctx) {
             if (VM.DEBUG) {
                 VM.trace("return", ctx.thread.pid, frame.methodInfo, stack[stack.length-1]);
             }
-            popFrame(1);
-            if (!frame.methodInfo)
+            if (ctx.frames.length == 1)
                 return;
+            popFrame(1);
             break;
         case 0xad: // lreturn
         case 0xaf: // dreturn
             if (VM.DEBUG) {
                 VM.trace("return", ctx.thread.pid, frame.methodInfo, stack[stack.length-1]);
             }
-            popFrame(2);
-            if (!frame.methodInfo)
+            if (ctx.frames.length == 1)
                 return;
+            popFrame(2);
             break;
         default:
             var opName = OPCODES[op];