revert backend changes

Author: zewenli98

py/torch_tensorrt/dynamo/backend/backends.py

@@ -96,19 +96,21 @@ def _pretraced_backend(
                 ),
             )
 
-        logger.debug("Post-AOT Autograd graph:\n" + str(gm.graph))
+            logger.debug("Post-AOT Autograd graph:\n" + str(gm.graph))
 
-        gm = post_lowering(gm, sample_inputs)
+            gm = post_lowering(gm, sample_inputs)
 
-        logger.debug("Lowered Input graph:\n " + str(gm.graph))
+            logger.debug("Lowered Input graph:\n " + str(gm.graph))
 
-        torchtrt_inputs = prepare_inputs(torch_inputs, disable_memory_format_check=True)
-        trt_compiled = compile_module(
-            gm,
-            torchtrt_inputs,
-            settings=settings,
-        )
-        return trt_compiled
+            torchtrt_inputs = prepare_inputs(
+                torch_inputs, disable_memory_format_check=True
+            )
+            trt_compiled = compile_module(
+                gm,
+                torchtrt_inputs,
+                settings=settings,
+            )
+            return trt_compiled
     except (AssertionError, RuntimeError):
         if not settings.pass_through_build_failures:
             logger.warning(