diff --git a/pystencils/astnodes.py b/pystencils/astnodes.py
index b1ed610e1a9262e407d65e3678d8b12d261845f4..2d3174a1a564bfd00633d36150d8119f7dacaec5 100644
--- a/pystencils/astnodes.py
+++ b/pystencils/astnodes.py
@@ -1,9 +1,13 @@
+from typing import Any, List, Optional, Sequence, Set, Union
+
+import jinja2
import sympy as sp
+
+from pystencils.data_types import TypedSymbol, cast_func, create_type
from pystencils.field import Field
-from pystencils.data_types import TypedSymbol, create_type, cast_func
-from pystencils.kernelparameters import FieldStrideSymbol, FieldPointerSymbol, FieldShapeSymbol
+from pystencils.kernelparameters import (FieldPointerSymbol, FieldShapeSymbol,
+ FieldStrideSymbol)
from pystencils.sympyextensions import fast_subs
-from typing import List, Set, Optional, Union, Any, Sequence
NodeOrExpr = Union['Node', sp.Expr]
@@ -130,6 +134,7 @@ class KernelFunction(Node):
defined in pystencils.kernelparameters.
If the parameter is related to one or multiple fields, these fields are referenced in the fields property.
"""
+
def __init__(self, symbol, fields):
self.symbol = symbol # type: TypedSymbol
self.fields = fields # type: Sequence[Field]
@@ -582,6 +587,7 @@ class TemporaryMemoryAllocation(Node):
size: number of elements to allocate
align_offset: the align_offset's element is aligned
"""
+
def __init__(self, typed_symbol: TypedSymbol, size, align_offset):
super(TemporaryMemoryAllocation, self).__init__(parent=None)
self.symbol = typed_symbol
@@ -639,3 +645,58 @@ class TemporaryMemoryFree(Node):
def early_out(condition):
from pystencils.cpu.vectorization import vec_all
return Conditional(vec_all(condition), Block([SkipIteration()]))
+
+
+class DestructuringBindingsForFieldClass(Node):
+ """
+ Defines all variables needed for describing a field (shape, pointer, strides)
+ """
+ CLASS_TO_MEMBER_DICT = {
+ FieldPointerSymbol: "data",
+ FieldShapeSymbol: "shape",
+ FieldStrideSymbol: "stride"
+ }
+ CLASS_NAME_TEMPLATE = jinja2.Template("Field<{{ dtype }}, {{ ndim }}>")
+
+ @property
+ def fields_accessed(self) -> Set['ResolvedFieldAccess']:
+ """Set of Field instances: fields which are accessed inside this kernel function"""
+ return set(o.field for o in self.atoms(ResolvedFieldAccess))
+
+ def __init__(self, body):
+ super(DestructuringBindingsForFieldClass, self).__init__()
+ self.headers = ['<Field.h>']
+ self.body = body
+
+ @property
+ def args(self) -> List[NodeOrExpr]:
+ """Returns all arguments/children of this node."""
+ return set()
+
+ @property
+ def symbols_defined(self) -> Set[sp.Symbol]:
+ """Set of symbols which are defined by this node."""
+ undefined_field_symbols = {s for s in self.body.undefined_symbols
+ if isinstance(s, (FieldPointerSymbol, FieldShapeSymbol, FieldStrideSymbol))}
+ return undefined_field_symbols
+
+ @property
+ def undefined_symbols(self) -> Set[sp.Symbol]:
+ field_map = {f.name: f for f in self.fields_accessed}
+ undefined_field_symbols = self.symbols_defined
+ corresponding_field_names = {s.field_name for s in undefined_field_symbols if hasattr(s, 'field_name')}
+ corresponding_field_names |= {s.field_names[0] for s in undefined_field_symbols if hasattr(s, 'field_names')}
+ return {TypedSymbol(f, self.CLASS_NAME_TEMPLATE.render(dtype=field_map[f].dtype, ndim=field_map[f].ndim) + '&')
+ for f in corresponding_field_names} | \
+ (self.body.undefined_symbols - undefined_field_symbols)
+
+ def subs(self, subs_dict) -> None:
+ """Inplace! substitute, similar to sympy's but modifies the AST inplace."""
+ self.body.subs(subs_dict)
+
+ @property
+ def func(self):
+ return self.__class__
+
+ def atoms(self, arg_type) -> Set[Any]:
+ return self.body.atoms(arg_type) | {s for s in self.symbols_defined if isinstance(s, arg_type)}
diff --git a/pystencils/backends/cbackend.py b/pystencils/backends/cbackend.py
index 1c28e324981d7bc4f5ea3ee310ca4ede0ee4e5f8..7c4937d1f524fdd76299a0f86b97bae4377eab16 100644
--- a/pystencils/backends/cbackend.py
+++ b/pystencils/backends/cbackend.py
@@ -1,24 +1,30 @@
-import sympy as sp
from collections import namedtuple
-from sympy.core import S
from typing import Set
+
+import jinja2
+import sympy as sp
+from sympy.core import S
from sympy.printing.ccode import C89CodePrinter
-from pystencils.cpu.vectorization import vec_any, vec_all
+from pystencils.astnodes import (DestructuringBindingsForFieldClass,
+ KernelFunction, Node)
+from pystencils.cpu.vectorization import vec_all, vec_any
from pystencils.data_types import (PointerType, VectorType, address_of,
- cast_func, create_type, reinterpret_cast_func,
+ cast_func, create_type,
get_type_of_expression,
- vector_memory_access)
-from pystencils.fast_approximation import fast_division, fast_inv_sqrt, fast_sqrt
+ reinterpret_cast_func, vector_memory_access)
+from pystencils.fast_approximation import (fast_division, fast_inv_sqrt,
+ fast_sqrt)
+from pystencils.integer_functions import (bit_shift_left, bit_shift_right,
+ bitwise_and, bitwise_or, bitwise_xor,
+ int_div, int_power_of_2, modulo_ceil)
+from pystencils.kernelparameters import FieldPointerSymbol
try:
from sympy.printing.ccode import C99CodePrinter as CCodePrinter
except ImportError:
from sympy.printing.ccode import CCodePrinter # for sympy versions < 1.1
-from pystencils.integer_functions import bitwise_xor, bit_shift_right, bit_shift_left, bitwise_and, \
- bitwise_or, modulo_ceil, int_div, int_power_of_2
-from pystencils.astnodes import Node, KernelFunction
__all__ = ['generate_c', 'CustomCodeNode', 'PrintNode', 'get_headers', 'CustomSympyPrinter']
@@ -255,6 +261,30 @@ class CBackend:
result += "else " + false_block
return result
+ def _print_DestructuringBindingsForFieldClass(self, node: Node):
+ # Define all undefined symbols
+ undefined_field_symbols = node.symbols_defined
+ destructuring_bindings = ["%s = %s.%s%s;" %
+ (u.name,
+ u.field_name if hasattr(u, 'field_name') else u.field_names[0],
+ DestructuringBindingsForFieldClass.CLASS_TO_MEMBER_DICT[u.__class__],
+ "" if type(u) == FieldPointerSymbol else ("[%i]" % u.coordinate))
+ for u in undefined_field_symbols
+ ]
+ destructuring_bindings.sort() # only for code aesthetics
+ template = jinja2.Template(
+ """{
+ {% for binding in bindings -%}
+ {{ binding | indent(3) }}
+ {% endfor -%}
+ {{ block | indent(3) }}
+}
+
+""")
+ code = template.render(bindings=destructuring_bindings,
+ block=self._print(node.body))
+ return code
+
# ------------------------------------------ Helper function & classes -------------------------------------------------
diff --git a/pystencils/data_types.py b/pystencils/data_types.py
index 93ef5c1c798df3b0316fdd4232462e13a9415538..3f1a02c6833756985308282c49148fe0ecaa0153 100644
--- a/pystencils/data_types.py
+++ b/pystencils/data_types.py
@@ -108,7 +108,7 @@ class TypedSymbol(sp.Symbol):
obj = super(TypedSymbol, cls).__xnew__(cls, name)
try:
obj._dtype = create_type(dtype)
- except TypeError:
+ except (TypeError, ValueError):
# on error keep the string
obj._dtype = dtype
return obj
diff --git a/pystencils/field.py b/pystencils/field.py
index c1720654867fe5b86ad321e1a1c6b78ec9b328f6..0c3af6dfa4edec15cb0f1cdff4822083eaacc017 100644
--- a/pystencils/field.py
+++ b/pystencils/field.py
@@ -306,6 +306,10 @@ class Field(AbstractField):
def index_dimensions(self) -> int:
return len(self.shape) - len(self._layout)
+ @property
+ def ndim(self) -> int:
+ return len(self.shape)
+
@property
def layout(self):
return self._layout
diff --git a/pystencils_tests/test_destructuring_field_class.py b/pystencils_tests/test_destructuring_field_class.py
new file mode 100644
index 0000000000000000000000000000000000000000..248963ae3aab3a0fb10e5965478e174ccecb39f8
--- /dev/null
+++ b/pystencils_tests/test_destructuring_field_class.py
@@ -0,0 +1,34 @@
+# -*- coding: utf-8 -*-
+#
+# Copyright © 2019 Stephan Seitz <stephan.seitz@fau.de>
+#
+# Distributed under terms of the GPLv3 license.
+
+"""
+
+"""
+import sympy
+
+import pystencils
+from pystencils.astnodes import DestructuringBindingsForFieldClass
+
+
+def test_destructuring_field_class():
+ z, x, y = pystencils.fields("z, y, x: [2d]")
+
+ normal_assignments = pystencils.AssignmentCollection([pystencils.Assignment(
+ z[0, 0], x[0, 0] * sympy.log(x[0, 0] * y[0, 0]))], [])
+
+ ast = pystencils.create_kernel(normal_assignments)
+ print(pystencils.show_code(ast))
+
+ ast.body = DestructuringBindingsForFieldClass(ast.body)
+ print(pystencils.show_code(ast))
+
+
+def main():
+ test_destructuring_field_class()
+
+
+if __name__ == '__main__':
+ main()