pystencils type system: distinction between static and reinterpret cast

backends/cbackend.py

@@ -12,7 +12,7 @@ from pystencils.integer_functions import bitwise_xor, bit_shift_right, bit_shift
     bitwise_or, modulo_ceil
 from pystencils.astnodes import Node, KernelFunction
 from pystencils.data_types import create_type, PointerType, get_type_of_expression, VectorType, cast_func, \
-    vector_memory_access
+    vector_memory_access, reinterpret_cast_func
 
 __all__ = ['generate_c', 'CustomCodeNode', 'PrintNode', 'get_headers', 'CustomSympyPrinter']
 
@@ -251,7 +251,10 @@ class CustomSympyPrinter(CCodePrinter):
         }
         if hasattr(expr, 'to_c'):
             return expr.to_c(self._print)
-        if isinstance(expr, cast_func):
+        if isinstance(expr, reinterpret_cast_func):
+            arg, data_type = expr.args
+            return "*((%s)(& %s))" % (PointerType(data_type, restrict=False), self._print(arg))
+        elif isinstance(expr, cast_func):
             arg, data_type = expr.args
             if isinstance(arg, sp.Number):
                 return self._typed_number(arg, data_type)

data_types.py

@@ -56,6 +56,11 @@ class vector_memory_access(cast_func):
     nargs = (4,)
 
 
+# noinspection PyPep8Naming
+class reinterpret_cast_func(cast_func):
+    pass
+
+
 # noinspection PyPep8Naming
 class pointer_arithmetic_func(sp.Function, Boolean):
     @property

transformations.py

@@ -10,8 +10,8 @@ from sympy.tensor import IndexedBase
 from pystencils.assignment import Assignment
 from pystencils.assignment_collection.nestedscopes import NestedScopes
 from pystencils.field import Field, FieldType
-from pystencils.data_types import TypedSymbol, PointerType, StructType, get_base_type, cast_func, \
-    pointer_arithmetic_func, get_type_of_expression, collate_types, create_type
+from pystencils.data_types import TypedSymbol, PointerType, StructType, get_base_type, reinterpret_cast_func, \
+    cast_func, pointer_arithmetic_func, get_type_of_expression, collate_types, create_type
 from pystencils.kernelparameters import FieldPointerSymbol
 from pystencils.slicing import normalize_slice
 import pystencils.astnodes as ast
@@ -427,7 +427,7 @@ def resolve_field_accesses(ast_node, read_only_field_names=set(),
 
             if isinstance(get_base_type(field_access.field.dtype), StructType):
                 new_type = field_access.field.dtype.get_element_type(field_access.index[0])
-                result = cast_func(result, new_type)
+                result = reinterpret_cast_func(result, new_type)
 
             return visit_sympy_expr(result, enclosing_block, sympy_assignment)
         else: