Added a new decorator and tagged a few opts for optimization when using the gpu…

theano/tensor/opt.py

@@ -315,6 +315,12 @@ def register_canonicalize(lopt, *tags, **kwargs):
     return lopt
 
 
+def register_canonicalize_tags(*tags, **kwargs):
+    def register(lopt):
+        return register_canonicalize(lopt, *tags, **kwargs)
+    return register
+
+                    
 def register_stabilize(lopt, *tags, **kwargs):
     name = (kwargs and kwargs.pop('name')) or lopt.__name__
     compile.optdb['stabilize'].register(name, lopt, 'fast_run', *tags)
@@ -1304,7 +1310,7 @@ def local_track_shape_i(node):
 
 
 @register_specialize
-@register_canonicalize
+@register_canonicalize_tags('gpu')
 @gof.local_optimizer([Subtensor])
 def local_subtensor_make_vector(node):
     # replace all subtensor(make_vector) like:
@@ -1354,8 +1360,7 @@ def local_subtensor_make_vector(node):
 
 #TODO: the other optimization for and, or, xor, le and ge see ticket #496.
 
-
-@register_canonicalize
+@register_canonicalize_tags('fast_compile')
 @register_specialize
 @gof.local_optimizer([T.Elemwise])
 def local_useless_elemwise(node):
@@ -3508,7 +3513,7 @@ def local_reduce_join(node):
         #else the reduction do something about the dtype.
 
 
-@register_canonicalize
+@register_canonicalize_tags('fast_compile')
 @gof.local_optimizer(ALL_REDUCE)
 def local_cut_useless_reduce(node):
     """Sum(a, axis=[]) -> a  """