C backend: no dependence to cgen package any more

ast.py

@@ -341,7 +341,7 @@ class TemporaryMemoryAllocation(Node):
 
     @property
     def symbolsDefined(self):
-        return set([self._symbol])
+        return set([self.symbol])
 
     @property
     def symbolsRead(self):
@@ -349,12 +349,12 @@ class TemporaryMemoryAllocation(Node):
 
     @property
     def args(self):
-        return [self._symbol]
+        return [self.symbol]
 
 
 class TemporaryMemoryFree(Node):
     def __init__(self, typedSymbol):
-        self._symbol = typedSymbol
+        self.symbol = typedSymbol
 
     @property
     def symbolsDefined(self):

backends/cbackend.py

-import cgen as c
+import textwrap
 from sympy.utilities.codegen import CCodePrinter
 from pystencils.ast import Node
 
@@ -40,9 +40,6 @@ class CustomCppCode(Node):
     def symbolsRead(self):
         return self._symbolsRead
 
-    def generateC(self):
-        return c.LiteralLines(self._code)
-
 
 class PrintNode(CustomCppCode):
     def __init__(self, symbolToPrint):
@@ -58,6 +55,7 @@ class CBackend:
     def __init__(self, cuda=False):
         self.cuda = cuda
         self.sympyPrinter = CustomSympyPrinter()
+        self._indent = "   "
 
     def __call__(self, node):
         return str(self._print(node))
@@ -70,46 +68,30 @@ class CBackend:
         raise NotImplementedError("CBackend does not support node of type " + cls.__name__)
 
     def _print_KernelFunction(self, node):
-        functionArguments = [MyPOD(s.dtype, s.name) for s in node.parameters]
+        functionArguments = ["%s %s" % (s.dtype, s.name) for s in node.parameters]
         prefix = "__global__ void" if self.cuda else "void"
-        functionPOD = MyPOD(prefix, node.functionName, )
-        funcDeclaration = c.FunctionDeclaration(functionPOD, functionArguments)
-        return c.FunctionBody(funcDeclaration, self._print(node.body))
+        funcDeclaration = "%s %s(%s)" % (prefix, node.functionName, ", ".join(functionArguments))
+        body = self._print(node.body)
+        return funcDeclaration + "\n" + body
 
     def _print_Block(self, node):
-        return c.Block([self._print(child) for child in node.args])
+        blockContents = "\n".join([self._print(child) for child in node.args])
+        return "{\n%s\n}" % (textwrap.indent(blockContents, self._indent))
 
     def _print_PragmaBlock(self, node):
-        class PragmaGenerable(c.Generable):
-            def __init__(self, line, block):
-                self._line = line
-                self._block = block
-
-            def generate(self):
-                yield self._line
-                for e in self._block.generate():
-                    yield e
-        return PragmaGenerable(node.pragmaLine, self._print_Block(node))
+        return "%s\n%s" % (node.pragmaLine, self._print_Block(node))
 
     def _print_LoopOverCoordinate(self, node):
-        class LoopWithOptionalPrefix(c.CustomLoop):
-            def __init__(self, intro_line, body, prefixLines=[]):
-                super(LoopWithOptionalPrefix, self).__init__(intro_line, body)
-                self.prefixLines = prefixLines
-
-            def generate(self):
-                for l in self.prefixLines:
-                    yield l
-
-                for e in super(LoopWithOptionalPrefix, self).generate():
-                    yield e
-
         counterVar = node.loopCounterName
         start = "int %s = %s" % (counterVar, self.sympyPrinter.doprint(node.start))
         condition = "%s < %s" % (counterVar, self.sympyPrinter.doprint(node.stop))
         update = "%s += %s" % (counterVar, self.sympyPrinter.doprint(node.step),)
         loopStr = "for (%s; %s; %s)" % (start, condition, update)
-        return LoopWithOptionalPrefix(loopStr, self._print(node.body), prefixLines=node.prefixLines)
+
+        prefix = "\n".join(node.prefixLines)
+        if prefix:
+            prefix += "\n"
+        return "%s%s\n%s" % (prefix, loopStr, self._print(node.body))
 
     def _print_SympyAssignment(self, node):
         dtype = ""
@@ -118,19 +100,17 @@ class CBackend:
                 dtype = "const " + node.lhs.dtype + " "
             else:
                 dtype = node.lhs.dtype + " "
-
-        return c.Assign(dtype + self.sympyPrinter.doprint(node.lhs),
-                        self.sympyPrinter.doprint(node.rhs))
+        return "%s %s = %s;" % (dtype, self.sympyPrinter.doprint(node.lhs), self.sympyPrinter.doprint(node.rhs))
 
     def _print_TemporaryMemoryAllocation(self, node):
-        return c.Assign(node.symbol.dtype + " * " + self.sympyPrinter.doprint(node.symbol),
-                        "new %s[%s]" % (node.symbol.dtype, self.sympyPrinter.doprint(node.size)))
+        return "%s * %s = new %s[%s];" % (node.symbol.dtype, self.sympyPrinter.doprint(node.symbol),
+                                         node.symbol.dtype, self.sympyPrinter.doprint(node.size))
 
     def _print_TemporaryMemoryFree(self, node):
-        return c.Statement("delete [] %s" % (self.sympyPrinter.doprint(node.symbol),))
+        return "delete [] %s;" % (self.sympyPrinter.doprint(node.symbol),)
 
     def _print_CustomCppCode(self, node):
-        return c.LiteralLines(node.code)
+        return node.code
 
 
 # ------------------------------------------ Helper function & classes -------------------------------------------------
@@ -155,13 +135,4 @@ class CustomSympyPrinter(CCodePrinter):
     def _print_Piecewise(self, expr):
         """Print piecewise in one line (remove newlines)"""
         result = super(CustomSympyPrinter, self)._print_Piecewise(expr)
-        return result.replace("\n", "")
-
-
-class MyPOD(c.Declarator):
-    def __init__(self, dtype, name):
-        self.dtype = dtype
-        self.name = name
-
-    def get_decl_pair(self):
-        return [self.dtype], self.name
+        return result.replace("\n", "")
\ No newline at end of file

transformations.py

@@ -364,7 +364,7 @@ def splitInnerLoop(astNode, symbolGroups):
         assignmentGroups.append(assignmentGroup)
 
     newLoops = [innerLoop.newLoopWithDifferentBody(ast.Block(group)) for group in assignmentGroups]
-    innerLoop.parent.replace(innerLoop, newLoops)
+    innerLoop.parent.replace(innerLoop, ast.Block(newLoops))
 
     for tmpArray in symbolsWithTemporaryArray:
         outerLoop.parent.insertFront(ast.TemporaryMemoryAllocation(tmpArray, innerLoop.stop))