Code refactoring

theano/tensor/opt.py

@@ -291,6 +291,11 @@ def inplace_elemwise_optimizer_op(OP):
         nb_change_no_validate = 0
         chk = fgraph.checkpoint()
 
+        if fgraph.update_mapping:
+            update_outs = [fgraph.outputs[i] for i in fgraph.update_mapping]
+        else:
+            update_outs = []
+
         for node in list(graph.io_toposort(fgraph.inputs, fgraph.outputs)):
             op = node.op
             # gpuarray GpuElemwise inherit from Elemwise
@@ -319,7 +324,6 @@ def inplace_elemwise_optimizer_op(OP):
 
             raised_warning = not verbose
 
-            update_outs = [fgraph.outputs[i] for i in fgraph.update_mapping]
             for candidate_output in candidate_outputs:
 
                 # If the output of the node can be established as an update
@@ -328,7 +332,6 @@ def inplace_elemwise_optimizer_op(OP):
                 # inplace on the input it's meant to update
                 candidate_out_var = node.outputs[candidate_output]
                 sorted_candidate_inputs = candidate_inputs
-                if fgraph.update_mapping:
 
                 if candidate_out_var in update_outs:
 
@@ -369,8 +372,7 @@ def inplace_elemwise_optimizer_op(OP):
                             other_vars.append(inp_idx)
 
                     sorted_candidate_inputs = (updated_vars +
-                                                   vars_from_inplace +
-                                                   other_vars)
+                                               vars_from_inplace + other_vars)
 
                 for candidate_input in sorted_candidate_inputs:
                     # remove inputs that don't have the same dtype as the output