added C code for the increment case

theano/sandbox/cuda/basic_ops.py

@@ -2511,6 +2511,23 @@ class GpuIncSubtensor(tensor.IncSubtensor, GpuOp):
             %(fail)s;
         }""" % locals()
 
+    def add_to_xview(self, x, fail):
+
+        return """
+
+        PyObject * add_result =  CudaNdarray_inplace_add(xview, py_%(x)s);
+
+        if (! add_result )
+        {
+            Py_DECREF(xview);
+            %(fail)s;
+        }
+        else
+        {
+            Py_DECREF(add_result);
+        }
+        """ % locals()
+
     def c_code_cache_version(self):
         # TODO: cooperate with parent class' C code
         return ()

theano/sandbox/cuda/cuda_ndarray.cu

@@ -1740,7 +1740,7 @@ CudaNdarray_inplace_elemwise(PyObject* py_self, PyObject * py_other, operator_t
  * It returns py_self on success with an additional reference. Else NULL.
  */
 // Will be called by __iadd__ in Python
-static PyObject *
+PyObject *
 CudaNdarray_inplace_add(PyObject* py_self, PyObject * py_other)
 {
     if (CudaNdarray_inplace_elemwise(py_self, py_other, IADD))

theano/sandbox/cuda/cuda_ndarray.cuh

@@ -144,7 +144,7 @@ CudaNdarray_Equal(CudaNdarray *cnda1, CudaNdarray *cnda2);
 /****
  *  Set the idx'th dimension to value d.
  *
- *  Updates the log2dim shaddow array.
+ *  Updates the log2dim shadow array.
  *
  *  Does not sync structure to host.
  */
@@ -441,6 +441,7 @@ int fprint_CudaNdarray(FILE * fd, const CudaNdarray *self);
 
 
 PyObject * CudaNdarray_View(const CudaNdarray * self);
+CudaNdarray_inplace_add(PyObject* py_self, PyObject * py_other);
 
 
 #endif

theano/tensor/basic.py

@@ -4648,6 +4648,8 @@ class IncSubtensor(Op):
 
         copy_into = self.copy_into("xview", y)
 
+        add_to_xview = self.add_to_xview(y, fail)
+
         make_modification = """
         if (%(op_is_set)s)
         {
@@ -4659,19 +4661,7 @@ class IncSubtensor(Op):
         }
         else
         {
-            PyArrayObject * add_rval = (PyArrayObject*)PyNumber_InPlaceAdd(
-                    (PyObject*)xview, py_%(y)s);
-            if (add_rval)
-            {
-                assert (PyArray_Check((PyObject*)add_rval));
-                assert (PyArray_DATA(add_rval) == PyArray_DATA(xview));
-                Py_DECREF(add_rval);
-            }
-            else
-            {
-                Py_DECREF(xview);
-                %(fail)s;
-            }
+            %(add_to_xview)s
         }
         """ % locals()
 
@@ -4773,6 +4763,24 @@ class IncSubtensor(Op):
         # On CPU there is nothing to do
         return ""
 
+    def add_to_xview(self, x, fail):
+        """ Return C code to add x to xview. Should DECREF xview if the
+        add fails."""
+
+        return """
+            PyArrayObject * add_rval = (PyArrayObject*)PyNumber_InPlaceAdd(
+                    (PyObject*)xview, py_%(x)s);
+            if (add_rval)
+            {
+                assert (PyArray_Check((PyObject*)add_rval));
+                assert (PyArray_DATA(add_rval) == PyArray_DATA(xview));
+                Py_DECREF(add_rval);
+            }
+            else
+            {
+                Py_DECREF(xview);
+                %(fail)s;
+            }""" % locals()
 
     def infer_shape(self, node, shapes):
         return [shapes[0]]