Fix field size

Fixes #32 (closed) and #31 (closed) and #3 (closed) and #7 (closed)

pystencils/cpu/cpujit.py

@@ -375,9 +375,11 @@ def create_function_boilerplate_code(parameter_info, name, ast_node, insert_chec
                 np_dtype = field.dtype.numpy_dtype
                 item_size = np_dtype.itemsize
 
-                aligned = any([a.lhs.args[2] for a in ast_node.assignments if
-                               hasattr(a, 'lhs') and isinstance(a.lhs, cast_func) and
-                               hasattr(a.lhs, 'dtype') and isinstance(a.lhs.dtype, VectorType)])
+                aligned = False
+                if ast_node.assignments:
+                    aligned = any([a.lhs.args[2] for a in ast_node.assignments
+                                   if hasattr(a, 'lhs') and isinstance(a.lhs, cast_func)
+                                   and hasattr(a.lhs, 'dtype') and isinstance(a.lhs.dtype, VectorType)])
 
                 if ast_node.instruction_set and aligned:
                     byte_width = ast_node.instruction_set['width'] * item_size
@@ -498,12 +500,16 @@ class ExtensionModuleCode:
         self._ast_nodes = []
         self._function_names = []
         self._custom_backend = custom_backend
+        self._code_string = str()
+        self._code_hash = None
 
     def add_function(self, ast, name=None):
         self._ast_nodes.append(ast)
         self._function_names.append(name if name is not None else ast.function_name)
 
-    def write_to_file(self, restrict_qualifier, function_prefix, file):
+    def create_code_string(self, restrict_qualifier, function_prefix):
+        self._code_string = str()
+
         headers = {'<math.h>', '<stdint.h>'}
         for ast in self._ast_nodes:
             headers.update(get_headers(ast))
@@ -512,19 +518,28 @@ class ExtensionModuleCode:
         header_list.insert(0, '"Python.h"')
 
         includes = "\n".join(["#include %s" % (include_file,) for include_file in header_list])
-        print(includes, file=file)
-        print("\n", file=file)
-        print(f"#define RESTRICT {restrict_qualifier}", file=file)
-        print(f"#define FUNC_PREFIX {function_prefix}", file=file)
-        print("\n", file=file)
+        self._code_string += includes
+        self._code_string += "\n"
+        self._code_string += f"#define RESTRICT {restrict_qualifier} \n"
+        self._code_string += f"#define FUNC_PREFIX {function_prefix}"
+        self._code_string += "\n"
 
         for ast, name in zip(self._ast_nodes, self._function_names):
             old_name = ast.function_name
             ast.function_name = "kernel_" + name
-            print(generate_c(ast, custom_backend=self._custom_backend), file=file)
-            print(create_function_boilerplate_code(ast.get_parameters(), name, ast), file=file)
+            self._code_string += generate_c(ast, custom_backend=self._custom_backend)
+            self._code_string += create_function_boilerplate_code(ast.get_parameters(), name, ast)
             ast.function_name = old_name
-        print(create_module_boilerplate_code(self.module_name, self._function_names), file=file)
+
+        self._code_hash = "mod_" + hashlib.sha256(self._code_string.encode()).hexdigest()
+        self._code_string += create_module_boilerplate_code(self._code_hash, self._function_names)
+
+    def get_hash_of_code(self):
+        return self._code_hash
+
+    def write_to_file(self, file):
+        assert self._code_string, "The code must be generated first"
+        print(self._code_string, file=file)
 
 
 def compile_module(code, code_hash, base_dir):
@@ -548,7 +563,7 @@ def compile_module(code, code_hash, base_dir):
 
     if not os.path.exists(object_file):
         with file_handle_for_atomic_write(src_file) as f:
-            code.write_to_file(compiler_config['restrict_qualifier'], function_prefix, f)
+            code.write_to_file(f)
 
         if windows:
             compile_cmd = ['cl.exe', '/c', '/EHsc'] + compiler_config['flags'].split()
@@ -582,15 +597,15 @@ def compile_module(code, code_hash, base_dir):
 def compile_and_load(ast, custom_backend=None):
     cache_config = get_cache_config()
 
-    generated_code = generate_c(ast, dialect='c', custom_backend=custom_backend)
-    fields_accessed = str(ast.fields_accessed)
+    compiler_config = get_compiler_config()
+    function_prefix = '__declspec(dllexport)' if compiler_config['os'].lower() == 'windows' else ''
 
-    # Also the information of the field size should be contained in the hash string. Due to padding the generated code
-    # can look similar for different field sizes.
-    code_hash_str = "mod_" + hashlib.sha256((generated_code + fields_accessed).encode()).hexdigest()
-    code = ExtensionModuleCode(module_name=code_hash_str, custom_backend=custom_backend)
+    code = ExtensionModuleCode(custom_backend=custom_backend)
     code.add_function(ast, ast.function_name)
 
+    code.create_code_string(compiler_config['restrict_qualifier'], function_prefix)
+    code_hash_str = code.get_hash_of_code()
+
     if cache_config['object_cache'] is False:
         with TemporaryDirectory() as base_dir:
             lib_file = compile_module(code, code_hash_str, base_dir)