Fix a couple of inaccurate comments in cfg_ir.py

kernel/modelverse_jit/cfg_ir.py

@@ -1078,7 +1078,7 @@ def get_directly_reachable_blocks(block):
 
 def get_reachable_blocks(entry_point):
     """Constructs the set of all reachable vertices from the given block."""
-    # This is a simple O(n^2) algorithm. Maybe a faster algorithm is more appropriate here.
+    # This is a simple O(n) algorithm.
     def __add_block_children(block, results):
         for child in get_directly_reachable_blocks(block):
             if child not in results:
@@ -1092,7 +1092,7 @@ def get_reachable_blocks(entry_point):
 def get_all_reachable_blocks(entry_point):
     """Constructs the set of all reachable vertices, for every block that is
        reachable from the given entry point."""
-    # This is a simple O(n^3) algorithm. Maybe a faster algorithm is more appropriate here.
+    # This is a simple O(n^2) algorithm. Maybe a faster algorithm is more appropriate here.
     results = {}
     all_blocks = get_reachable_blocks(entry_point)
     results[entry_point] = all_blocks

kernel/modelverse_kernel/request_handler.py

@@ -66,7 +66,7 @@ class RequestHandler(object):
         # (generator_stack index, [(exception type, handler function)])
         # tuples.
         self.exception_handlers = []
-        self.produce_stack_trace = True
+        self.produce_stack_trace = False
         self.handlers = {
             'CALL' : self.execute_call,
             'CALL_ARGS' : self.execute_call_args,