[Bugfix] Safeguard against submodule parameter deletion in decompress_model (#347)

* safeguard against removing parameters not immediately on the module

Signed-off-by: Kyle Sayers <kylesayrs@gmail.com>

* add safeguard to compress method

Signed-off-by: Kyle Sayers <kylesayrs@gmail.com>

* safeguard against state dict creation

Signed-off-by: Kyle Sayers <kylesayrs@gmail.com>

---------

Signed-off-by: Kyle Sayers <kylesayrs@gmail.com>

Author: kylesayrs

src/compressed_tensors/compressors/model_compressors/model_compressor.py

@@ -400,7 +400,10 @@ def compress_model(self, model: Module):
 
                 # in the future, support compression on same device
                 with align_module_device(module, execution_device=exec_device):
-                    state_dict = module.state_dict(prefix=f"{prefix}.")
+                    state_dict = {
+                        f"{prefix}.{name}": param
+                        for name, param in module.named_parameters(recurse=False)
+                    }
 
                 # quantization first
                 if prefix in module_to_scheme:
@@ -421,7 +424,7 @@ def compress_model(self, model: Module):
 
                 # remove any existing parameters
                 offload_device = get_offloaded_device(module)
-                for name, _ in list(module.named_parameters()):
+                for name, _ in list(module.named_parameters(recurse=False)):
                     delete_offload_parameter(module, name)
 
                 # replace with compressed parameters
@@ -458,7 +461,10 @@ def decompress_model(self, model: Module):
             if prefix in module_to_scheme or prefix in sparse_compression_targets:
                 # in the future, support decompression on same device
                 with align_module_device(module, execution_device="cpu"):
-                    state_dict = module.state_dict(prefix=f"{prefix}.")
+                    state_dict = {
+                        f"{prefix}.{name}": param
+                        for name, param in module.named_parameters(recurse=False)
+                    }
 
                 # sparsity first
                 if prefix in sparse_compression_targets:
@@ -483,7 +489,7 @@ def decompress_model(self, model: Module):
                 # remove any existing parameters
                 exec_device = get_execution_device(module)
                 offload_device = get_offloaded_device(module)
-                for name, _ in list(module.named_parameters()):
+                for name, _ in list(module.named_parameters(recurse=False)):
                     delete_offload_parameter(module, name)
 
                 # replace with decompressed parameters