diff --git a/pystencils/backends/cbackend.py b/pystencils/backends/cbackend.py
index 8eb44766199e2aaad990bab167fc9267bc4017c9..1c28e324981d7bc4f5ea3ee310ca4ede0ee4e5f8 100644
--- a/pystencils/backends/cbackend.py
+++ b/pystencils/backends/cbackend.py
@@ -40,10 +40,39 @@ def generate_c(ast_node: Node, signature_only: bool = False, dialect='c') -> str
Returns:
C-like code for the ast node and its descendants
"""
+ global_declarations = get_global_declarations(ast_node)
+ for d in global_declarations:
+ if hasattr(ast_node, "global_variables"):
+ ast_node.global_variables.update(d.symbols_defined)
+ else:
+ ast_node.global_variables = d.symbols_defined
printer = CBackend(signature_only=signature_only,
vector_instruction_set=ast_node.instruction_set,
dialect=dialect)
- return printer(ast_node)
+ code = printer(ast_node)
+ if not signature_only and isinstance(ast_node, KernelFunction):
+ code = "\n" + code
+ for declaration in global_declarations:
+ code = printer(declaration) + "\n" + code
+
+ return code
+
+
+def get_global_declarations(ast):
+ global_declarations = []
+
+ def visit_node(sub_ast):
+ if hasattr(sub_ast, "required_global_declarations"):
+ nonlocal global_declarations
+ global_declarations += sub_ast.required_global_declarations
+
+ if hasattr(sub_ast, "args"):
+ for node in sub_ast.args:
+ visit_node(node)
+
+ visit_node(ast)
+
+ return set(global_declarations)
def get_headers(ast_node: Node) -> Set[str]:
diff --git a/pystencils_tests/test_global_definitions.py b/pystencils_tests/test_global_definitions.py
new file mode 100644
index 0000000000000000000000000000000000000000..9b6609eb89649bee63d6db813d64d3660ed859f0
--- /dev/null
+++ b/pystencils_tests/test_global_definitions.py
@@ -0,0 +1,146 @@
+# -*- coding: utf-8 -*-
+#
+# Copyright © 2019 Stephan Seitz <stephan.seitz@fau.de>
+#
+# Distributed under terms of the GPLv3 license.
+
+"""
+
+"""
+
+import sympy
+
+import pystencils.astnodes
+from pystencils.backends.cbackend import CBackend
+from pystencils.data_types import TypedSymbol
+
+
+class BogusDeclaration(pystencils.astnodes.Node):
+ """Base class for all AST nodes."""
+
+ def __init__(self, parent=None):
+ self.parent = parent
+
+ @property
+ def args(self):
+ """Returns all arguments/children of this node."""
+ raise set()
+
+ @property
+ def symbols_defined(self):
+ """Set of symbols which are defined by this node."""
+ return {TypedSymbol('Foo', 'double')}
+
+ @property
+ def undefined_symbols(self):
+ """Symbols which are used but are not defined inside this node."""
+ set()
+
+ def subs(self, subs_dict):
+ """Inplace! substitute, similar to sympy's but modifies the AST inplace."""
+ for a in self.args:
+ a.subs(subs_dict)
+
+ @property
+ def func(self):
+ return self.__class__
+
+ def atoms(self, arg_type):
+ """Returns a set of all descendants recursively, which are an instance of the given type."""
+ result = set()
+ for arg in self.args:
+ if isinstance(arg, arg_type):
+ result.add(arg)
+ result.update(arg.atoms(arg_type))
+ return result
+
+
+class BogusUsage(pystencils.astnodes.Node):
+ """Base class for all AST nodes."""
+
+ def __init__(self, requires_global: bool, parent=None):
+ self.parent = parent
+ if requires_global:
+ self.required_global_declarations = [BogusDeclaration()]
+
+ @property
+ def args(self):
+ """Returns all arguments/children of this node."""
+ return set()
+
+ @property
+ def symbols_defined(self):
+ """Set of symbols which are defined by this node."""
+ return set()
+
+ @property
+ def undefined_symbols(self):
+ """Symbols which are used but are not defined inside this node."""
+ return {TypedSymbol('Foo', 'double')}
+
+ def subs(self, subs_dict):
+ """Inplace! substitute, similar to sympy's but modifies the AST inplace."""
+ for a in self.args:
+ a.subs(subs_dict)
+
+ @property
+ def func(self):
+ return self.__class__
+
+ def atoms(self, arg_type):
+ """Returns a set of all descendants recursively, which are an instance of the given type."""
+ result = set()
+ for arg in self.args:
+ if isinstance(arg, arg_type):
+ result.add(arg)
+ result.update(arg.atoms(arg_type))
+ return result
+
+
+def test_global_definitions_with_global_symbol():
+ # Teach our printer to print new ast nodes
+ CBackend._print_BogusUsage = lambda _, __: "// Bogus would go here"
+ CBackend._print_BogusDeclaration = lambda _, __: "// Declaration would go here"
+
+ 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.append(BogusUsage(requires_global=True))
+ print(pystencils.show_code(ast))
+ kernel = ast.compile()
+ assert kernel is not None
+
+ assert TypedSymbol('Foo', 'double') not in [p.symbol for p in ast.get_parameters()]
+
+
+def test_global_definitions_without_global_symbol():
+ # Teach our printer to print new ast nodes
+ CBackend._print_BogusUsage = lambda _, __: "// Bogus would go here"
+ CBackend._print_BogusDeclaration = lambda _, __: "// Declaration would go here"
+
+ 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.append(BogusUsage(requires_global=False))
+ print(pystencils.show_code(ast))
+ kernel = ast.compile()
+ assert kernel is not None
+
+ assert TypedSymbol('Foo', 'double') in [p.symbol for p in ast.get_parameters()]
+
+
+def main():
+ test_global_definitions_with_global_symbol()
+ test_global_definitions_without_global_symbol()
+
+
+if __name__ == '__main__':
+ main()