Fix signed comparison in op_jl

src/mudlib/zmachine/zcpu.py

@@ -251,16 +251,13 @@ class ZCpu:
         # Fallthrough: No args were equal to a.
         self._branch(False)
 
-    def op_jl(self, a, *others):
-        """Branch if the first argument is less than any subsequent
-        argument. Note that the second operand may be absent, in
-        which case there is no jump."""
-        for b in others:
+    def op_jl(self, a, b):
+        """Branch if the first argument is less than the second."""
+        a = self._make_signed(a)
+        b = self._make_signed(b)
         if a < b:
             self._branch(True)
-                return
-
-        # Fallthrough: No args were greater than a.
+        else:
             self._branch(False)
 
     def op_jg(self, a, b):