Merge pull request #3403 from nouiz/faster_merge

theano/gof/opt.py

@@ -810,6 +810,17 @@ class MergeOptimizer(Optimizer):
                     # No need to compare the op again, as it don't change.
                     if not inputs_match:
                         continue
+
+                    if hasattr(pairs[0][0].fgraph, 'destroy_handler'):
+                        # If both nodes have clients that destroy
+                        # them, we can't merge them.
+                        clients = pairs[0][0].clients + pairs[0][1].clients
+                        if sum([i in utils.flatten(c.op.destroy_map.values())
+                                for c, i in clients
+                                if c != 'output' and
+                                hasattr(c.op, 'destroy_map')]) > 1:
+                            continue
+
                 try:
                     fgraph.replace_all_validate(pairs, 'MergeOptimizer')
                 except InconsistencyError:

theano/gradient.py

@@ -3,10 +3,12 @@ from __future__ import print_function
 import six.moves.builtins as builtins
 import logging
 import time
+import traceback
 import warnings
 
 import numpy  # for numeric_grad
 from six import itervalues
+from six.moves import StringIO
 
 import theano
 
@@ -515,6 +517,17 @@ def grad(cost, wrt, consider_constant=None,
             elif disconnected_inputs == 'warn':
                 warnings.warn(message, stacklevel=2)
             elif disconnected_inputs == 'raise':
+                # Add the var trace
+                tr = getattr(var.tag, 'trace', [])
+                if len(tr) > 0:
+                    message += "\nBacktrace when the node is created:\n"
+
+                    # Print separate message for each element in the list of batcktraces
+                    sio = StringIO()
+                    for subtr in tr:
+                        traceback.print_list(subtr, sio)
+                    message += str(sio.getvalue())
+
                 raise DisconnectedInputError(message)
             else:
                 raise ValueError("Invalid value for keyword "

theano/printing.py

@@ -132,14 +132,8 @@ def debugprint(obj, depth=-1, print_type=False,
                             obj)
 
     scan_ops = []
-    for r, p in zip(results_to_print, profile_list):
-        # Add the parent scan op to the list as well
-        if (hasattr(r.owner, 'op') and
-                isinstance(r.owner.op, theano.scan_module.scan_op.Scan)):
-                    scan_ops.append(r)
-
-        if p is not None:
-            print("""
+    if any([p for p in profile_list if p is not None and p.fct_callcount > 0]):
+        print("""
 Timing Info
 -----------
 --> <time> <% time> - <total time> <% total time>'
@@ -157,6 +151,12 @@ N.B.:
   to remove when optimizing a graph because their <total time> is very low.
 """, file=_file)
 
+    for r, p in zip(results_to_print, profile_list):
+        # Add the parent scan op to the list as well
+        if (hasattr(r.owner, 'op') and
+                isinstance(r.owner.op, theano.scan_module.scan_op.Scan)):
+                    scan_ops.append(r)
+
         debugmode.debugprint(r, depth=depth, done=done, print_type=print_type,
                              file=_file, order=order, ids=ids,
                              scan_ops=scan_ops, stop_on_name=stop_on_name,