Automated rollback of commit c99fc34eeb

PiperOrigin-RevId: 261160111

tensorflow/python/ops/math_grad.py

@@ -1327,43 +1327,21 @@ def _PowGrad(op, grad):
   """Returns grad * (y*x^(y-1), z*log(x))."""
   x = op.inputs[0]
   y = op.inputs[1]
-  use_mul_no_nan = compat.forward_compatible(2019, 9, 14)
-  skip_input_indices = None
-  try:
-    skip_input_indices = op.skip_input_indices
-    # TODO(mrry): If `y` is a constant, we can combine `tf.sub()` and the
-    # constant `1` into a single constant op.
-    if skip_input_indices is not None and 1 in skip_input_indices and _IsScalar(
-        y):
+  z = op.outputs[0]
+  sx = array_ops.shape(x)
+  sy = array_ops.shape(y)
+  rx, ry = gen_array_ops.broadcast_gradient_args(sx, sy)
   x = math_ops.conj(x)
   y = math_ops.conj(y)
-      if use_mul_no_nan:
-        return gen_math_ops.mul_no_nan(y * math_ops.pow(x, y - 1), grad), None
+  z = math_ops.conj(z)
+
+  if compat.forward_compatible(2019, 9, 14):
+    gx = array_ops.reshape(
+        math_ops.reduce_sum(
+            gen_math_ops.mul_no_nan(y * math_ops.pow(x, y - 1), grad), rx), sx)
   else:
-        return grad * y * math_ops.pow(x, y - 1), None
-
-  except AttributeError:
-    # No gradient skipping, so do the full gradient computation
-    pass
-
-  (sx, rx, must_reduce_x), (sy, ry, must_reduce_y) = (
-      SmartBroadcastGradientArgs(x, y, grad))
-  x = math_ops.conj(x)
-  y = math_ops.conj(y)
-
-  if skip_input_indices is None or 0 not in skip_input_indices:
-    if use_mul_no_nan:
-      gx = gen_math_ops.mul_no_nan(y * math_ops.pow(x, y - 1), grad)
-    else:
-      gx = grad * y * math_ops.pow(x, y - 1)
-    if must_reduce_x:
-      gx = array_ops.reshape(math_ops.reduce_sum(gx, rx), sx)
-  else:
-    gx = None
-
-  if skip_input_indices is None or 1 not in skip_input_indices:
-    z = math_ops.conj(op.outputs[0])
-
+    gx = array_ops.reshape(
+        math_ops.reduce_sum(grad * y * math_ops.pow(x, y - 1), rx), sx)
   # Avoid false singularity at x = 0
   if x.dtype.is_complex:
     # real(x) < 0 is fine for the complex case
@@ -1373,15 +1351,11 @@ def _PowGrad(op, grad):
     mask = x > 0
   safe_x = array_ops.where(mask, x, array_ops.ones_like(x))
   log_x = array_ops.where(mask, math_ops.log(safe_x), array_ops.zeros_like(x))
-    if use_mul_no_nan:
-      gy = gen_math_ops.mul_no_nan(z * log_x, grad)
+  if compat.forward_compatible(2019, 9, 14):
+    gy = array_ops.reshape(
+        math_ops.reduce_sum(gen_math_ops.mul_no_nan(z * log_x, grad), ry), sy)
   else:
-      gy = grad * z * log_x
-    if must_reduce_y:
-      gy = array_ops.reshape(math_ops.reduce_sum(gy, ry), sy)
-  else:
-    gy = None
-
+    gy = array_ops.reshape(math_ops.reduce_sum(grad * z * log_x, ry), sy)
   return gx, gy
 
 
@@ -1449,39 +1423,15 @@ def _SquaredDifferenceGrad(op, grad):
   """Returns the gradient for (x-y)^2."""
   x = op.inputs[0]
   y = op.inputs[1]
-  skip_input_indices = None
-  try:
-    skip_input_indices = op.skip_input_indices
-  except AttributeError:
-    # No gradient skipping, so do the full gradient computation
-    pass
-
+  sx = array_ops.shape(x)
+  sy = array_ops.shape(y)
+  rx, ry = gen_array_ops.broadcast_gradient_args(sx, sy)
   with ops.control_dependencies([grad]):
     # The parens ensure that if grad is IndexedSlices, it'll get multiplied by
     # Tensor (not a number like 2.0) which causes it to convert to Tensor.
     x_grad = math_ops.scalar_mul(2.0, grad) * (x - y)
-
-  if (isinstance(grad, ops.Tensor) and
-      _ShapesFullySpecifiedAndEqual(x, y, grad)):
-    return x_grad, -x_grad
-
-  (sx, rx, must_reduce_x), (sy, ry, must_reduce_y) = (
-      SmartBroadcastGradientArgs(x, y, grad))
-
-  if skip_input_indices is not None and 0 in skip_input_indices:
-    gx = None
-  elif must_reduce_x:
-    gx = array_ops.reshape(math_ops.reduce_sum(x_grad, rx), sx)
-  else:
-    gx = x_grad
-
-  if skip_input_indices is not None and 1 in skip_input_indices:
-    gy = None
-  elif must_reduce_y:
-    gy = -array_ops.reshape(math_ops.reduce_sum(x_grad, ry), sy)
-  else:
-    gy = -x_grad
-  return (gx, gy)
+  return (array_ops.reshape(math_ops.reduce_sum(x_grad, rx), sx),
+          -array_ops.reshape(math_ops.reduce_sum(x_grad, ry), sy))
 
 
 # Logical operations have no gradients.