Merge pull request #713 from abergeron/cvm_gc

theano/gof/lazylinker_c.c.txt

@@ -771,6 +771,7 @@ int lazy_rec_eval(CLazyLinker * self, Py_ssize_t var_idx, PyObject*one, PyObject
 
           Py_INCREF(Py_None);
           err = PyList_SetItem(self->var_value_cells[i_idx], 0, Py_None);
+          self->var_computed[i_idx] = 0;
           if (err) goto fail;
         }
     }
@@ -863,6 +864,33 @@ CLazyLinker_call(PyObject *_self, PyObject *args, PyObject *kwds)
             }
         }
     }
+
+  /*
+    Clear everything that is left and not an output.  This is needed
+    for lazy evaluation since the current GC algo is too conservative
+    with lazy graphs.
+  */
+  if (self->allow_gc && !err)
+    {
+      for (Py_ssize_t i = 0; i < self->n_vars; ++i)
+        {
+          int do_cleanup = 1;
+          if (!self->var_has_owner[i] || !self->var_computed[i])
+            continue;
+          for (int j = 0; j < self->n_output_vars; ++j)
+            {
+              if (i == self->output_vars[j])
+                {
+                  do_cleanup = 0;
+                  break;
+                }
+            }
+          if (!do_cleanup)
+            continue;
+          Py_INCREF(Py_None);
+          PyList_SetItem(self->var_value_cells[i], 0, Py_None);
+        }
+    }
   Py_DECREF(one);
   Py_DECREF(zero);
   if (err)
@@ -944,7 +972,7 @@ static PyTypeObject lazylinker_ext_CLazyLinkerType = {
 
 static PyObject * get_version(PyObject *dummy, PyObject *args)
 {
-  PyObject *result = PyFloat_FromDouble(0.15);
+  PyObject *result = PyFloat_FromDouble(0.17);
   return result;
 }
 

theano/gof/lazylinker_c.py

@@ -13,7 +13,7 @@ if config.compiledir not in sys.path:
     sys.path.append(config.compiledir)
 
 force_compile = False
-version = 0.15 # must match constant returned in function get_version()
+version = 0.17 # must match constant returned in function get_version()
 
 
 try:

theano/gof/vm.py

@@ -408,9 +408,8 @@ class Stack(VM):
         # lazy evaluation. See discussion on theano-dev June 19 2012.
         if self.allow_gc:
             for v in storage_map:
-                if v.owner and 'output' not in zip(*v.clients)[0]:
+                if v.owner and not v in self.outputs:
                     storage_map[v][0] = None
-                    compute_map[v][0] = 0
 
 
 try: