Fix caching for PybindModules

src/pystencils_autodiff/backends/astnodes.py

@@ -94,8 +94,9 @@ class TorchModule(JinjaCppFile):
 
         super().__init__(ast_dict)
 
-    def generate_wrapper_function(self, kernel_ast):
-        return WrapperFunction(self.DESTRUCTURING_CLASS(generate_kernel_call(kernel_ast)),
+    @classmethod
+    def generate_wrapper_function(cls, kernel_ast):
+        return WrapperFunction(cls.DESTRUCTURING_CLASS(generate_kernel_call(kernel_ast)),
                                function_name='call_' + kernel_ast.function_name)
 
     def compile(self):
@@ -165,10 +166,12 @@ setup_pybind11(cfg)
 
         assert not self.is_cuda
 
-        cache_dir = get_cache_config()['object_cache']
         source_code = self.CPP_IMPORT_PREFIX + str(self)
-        file_name = join(cache_dir, f'{self.module_name}.cpp')
+        hash_str = _hash(source_code.encode()).hexdigest()
+        cache_dir = join(get_cache_config()['object_cache'], f'cppimport_{hash_str}')
+        file_name = join(cache_dir,  f'{self.module_name}.cpp')
 
+        os.makedirs(cache_dir, exist_ok=True)
         if not exists(file_name):
             write_file(file_name, source_code)
         # TODO: propagate extra headers
@@ -176,7 +179,8 @@ setup_pybind11(cfg)
             sys.path.append(cache_dir)
 
         try:
-            torch_extension = cppimport.imp(f'{self.module_name}')
-        except Exception:
+            torch_extension = cppimport.imp(self.module_name)
+        except Exception as e:
+            print(e)
             torch_extension = load(self.module_name, [file_name])
         return torch_extension