fix: Necessary default fixes for compile

py/torch_tensorrt/_compile.py

@@ -7,16 +7,23 @@
 import torch
 import torch.fx
 import torch_tensorrt.ts
-from torch._export import ExportedProgram
 from torch_tensorrt._enums import dtype
 from torch_tensorrt._Input import Input
-from torch_tensorrt.dynamo.compile import compile as dynamo_compile
+from torch_tensorrt._utils import sanitized_torch_version
 from torch_tensorrt.fx import InputTensorSpec
 from torch_tensorrt.fx.lower import compile as fx_compile
 from torch_tensorrt.fx.utils import LowerPrecision
 from torch_tensorrt.ts._compiler import compile as torchscript_compile
 from typing_extensions import TypeGuard
 
+from packaging import version
+
+DYNAMO_ENABLED = version.parse(sanitized_torch_version()) >= version.parse("2.1.dev")
+
+if DYNAMO_ENABLED:
+    from torch._export import ExportedProgram
+    from torch_tensorrt.dynamo.compile import compile as dynamo_compile
+
 logger = logging.getLogger(__name__)
 
 __all__ = [
@@ -64,7 +71,7 @@ def _parse_module_type(module: Any) -> _ModuleType:
         return _ModuleType.ts
     elif isinstance(module, torch.fx.GraphModule):
         return _ModuleType.fx
-    elif isinstance(module, ExportedProgram):
+    elif DYNAMO_ENABLED and isinstance(module, ExportedProgram):
         return _ModuleType.ep
     elif isinstance(module, torch.nn.Module):
         return _ModuleType.nn
@@ -93,13 +100,14 @@ def _get_target_ir(module_type: _ModuleType, ir: str) -> _IRType:
     else:
         if ir == "default":
             # Options are listed in order of preference
-            if module_is_fxable:
+            if DYNAMO_ENABLED and module_is_fxable:
                 logger.info("ir was set to default, using dynamo as ir")
                 return _IRType.dynamo
             elif module_is_tsable:
-                logger.warning(
-                    "Input graph is a Torchscript module but the ir provided is default (dynamo). Please set ir=torchscript to suppress the warning. Compiling the module with ir=torchscript"
-                )
+                if DYNAMO_ENABLED:
+                    logger.warning(
+                        "Input graph is a Torchscript module but the ir provided is default (dynamo). Please set ir=torchscript to suppress the warning. Compiling the module with ir=torchscript"
+                    )
                 return _IRType.ts
             elif module_is_exportable:
                 raise ValueError(