Remove buildbot error in DebugMode. Mark opt as remove inf.

theano/gof/opt.py

@@ -1407,9 +1407,11 @@ class PatternSub(LocalOptimizer):
     def __init__(self, in_pattern, out_pattern,
                  allow_multiple_clients=False,
                  skip_identities_fn=None, name=None, pdb=False,
-                 tracks=(), get_nodes=None):
+                 tracks=(), get_nodes=None,
+                 values_eq_approx=None):
         self.in_pattern = in_pattern
         self.out_pattern = out_pattern
+        self.values_eq_approx = values_eq_approx
         if isinstance(in_pattern, (list, tuple)):
             self.op = self.in_pattern[0]
         elif isinstance(in_pattern, dict):
@@ -1451,6 +1453,8 @@ class PatternSub(LocalOptimizer):
                 ret = self.transform(real_node, get_nodes=False)
                 if ret is not False and ret is not None:
                     assert len(real_node.outputs) == len(ret)
+                    if self.values_eq_approx:
+                        ret.tag.values_eq_approx = self.values_eq_approx
                     return dict(izip(real_node.outputs, ret))
 
         if node.op != self.op:
@@ -1534,8 +1538,10 @@ class PatternSub(LocalOptimizer):
                 else:
                     return pattern.clone()
             p = self.out_pattern
-            new = build(p, u)
-            return [new]
+            ret = build(p, u)
+            if self.values_eq_approx:
+                ret.tag.values_eq_approx = self.values_eq_approx
+            return [ret]
         else:
             return False
 

theano/tensor/nnet/sigm.py

@@ -18,6 +18,7 @@ from theano.configparser import AddConfigVar, BoolParam
 from theano.printing import pprint
 from theano.tensor import basic as tensor
 from theano.tensor import elemwise, opt, NotScalarConstantError
+from theano.tensor.type import values_eq_approx_remove_inf
 
 
 ############
@@ -314,6 +315,9 @@ theano.compile.optdb['uncanonicalize'].register("local_hard_sigmoid",
 
 
 class ScalarSoftplus(scalar.UnaryScalarOp):
+    """
+    This help numerical stability.
+    """
     @staticmethod
     def static_impl(x):
         if x < -30.0:
@@ -378,6 +382,7 @@ logsigm_to_softplus = gof.PatternSub(
     (tensor.log, (sigmoid, 'x')),
     (tensor.neg, (softplus, (tensor.neg, 'x'))),
     allow_multiple_clients=True,
+    values_eq_approx=values_eq_approx_remove_inf,
     skip_identities_fn=_skip_mul_1)
 
 
@@ -403,12 +408,14 @@ log1msigm_to_softplus = gof.PatternSub(
             (sigmoid, 'x'))),
     (tensor.neg, (softplus, 'x')),
     allow_multiple_clients=True,
+    values_eq_approx=values_eq_approx_remove_inf,
     skip_identities_fn=_skip_mul_1)
 
 log1pexp_to_softplus = gof.PatternSub(
     (tensor.log1p,
      (tensor.exp, 'x')),
     (softplus, 'x'),
+    values_eq_approx=values_eq_approx_remove_inf,
     allow_multiple_clients=True)
 
 opt.register_stabilize(logsigm_to_softplus, name='logsigm_to_softplus')

theano/tensor/tests/test_opt.py

@@ -4228,7 +4228,9 @@ def test_constant_get_stabilized():
     """
     x2 = T.scalar()
     y2 = T.log(1 + T.exp(x2))
-    f2 = theano.function([x2], y2)
+    mode = theano.compile.get_default_mode()
+    mode.check_isfinite = False
+    f2 = theano.function([x2], y2, mode=mode)
     try:
         assert len(f2.maker.fgraph.toposort()) == 1
         assert f2.maker.fgraph.toposort()[0].op == \
@@ -4237,14 +4239,14 @@ def test_constant_get_stabilized():
 
         x = T.as_tensor_variable(800)
         y = T.log(1 + T.exp(x))
-        f = theano.function([], y)
+        f = theano.function([], y, mode=mode)
         assert len(f.maker.fgraph.toposort()) == 0
         assert numpy.isinf(f())
 
         # When this error is fixed, the following line should be ok.
         assert f() == 800, f()
 
-    except (AssertionError, theano.compile.debugmode.InvalidValueError):
+    except AssertionError:
         raise SkipTest('Theano optimizes constant before stabilization. '
                        'This breaks stabilization optimization in some '
                        'cases. See #504.')