make a white list of dtype supported on the gpu and not a blacklist.

theano/sandbox/cuda/opt.py

@@ -99,12 +99,16 @@ gpu_cut_copies.register('cut_gpu_constant_transfers', tensor.opt.constant_foldin
 #botering with this useless pattern.
 compile.optdb['canonicalize'].register('local_cut_gpu_host_gpu', local_cut_gpu_host_gpu, 'fast_run')
 
-def float64_in_elemwise(op):
+#'float64', 'complex128' and 'complex64' are not supported in elemwise on the gpu.
+elemwise_cuda_dtype_supported=['float32','uint8','int8','uint16','int16',
+                      'uint32','int32''uint64','int64']
+
+def dtype_in_elemwise_supported(op):
     """
-    Return True of the Elemwise op have float64 in it.
+    Return True of the Elemwise op is supported on the gpu.
     Return False otherwise.
 
-    :note: This can happen with the Composite Op.
+    :note: We need to check inside the Composite op.
     """
     def get_all_basic_scalar(composite_op):
         l=[]
@@ -118,9 +122,10 @@ def float64_in_elemwise(op):
         if isinstance(op.scalar_op, theano.scalar.Composite):
             scals = get_all_basic_scalar(op.scalar_op)
             for s in scals:
-                if any([i.type.dtype=='float64' for i in s.inputs+s.outputs]):
-                    return True
-    return False
+                if any([i.type.dtype not in elemwise_cuda_dtype_supported
+                        for i in s.inputs+s.outputs]):
+                    return False
+    return True
 
 
 
@@ -131,7 +136,7 @@ def local_gpu_elemwise_0(node):
     """elemwise(..., host_from_gpu, ...)
        -> host_from_gpu(elemwise(gpu_from_host, ..., gpu_from_host)
     """
-    if isinstance(node.op, tensor.Elemwise) and not float64_in_elemwise(node.op):
+    if isinstance(node.op, tensor.Elemwise) and dtype_in_elemwise_supported(node.op):
         if numpy.any([i.owner and isinstance(i.owner.op, HostFromGpu) for i in node.inputs]):
             if numpy.all([o.type.dtype == 'float32' for o in node.outputs]):
                 #don't set any inplace pattern. gpu_insert_inplace_optimizer will do it later
@@ -174,7 +179,7 @@ def local_gpu_elemwise_1(node):
         if (host_i.owner and
             isinstance(host_i.owner.op, tensor.Elemwise) and
             len(host_i.clients)==1 and
-            not float64_in_elemwise(node.op)):
+            dtype_in_elemwise_supported(node.op)):
 
             elemwise_node = host_i.owner
             #don't set any inplace pattern. gpu_insert_inplace_optimizer will do it later