Error out on in-place (unary) ops on tensors that have internal overlap (#17927)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/17927
ghimport-source-id: 626d321e430b6b5c0ea3aa1eb9df8c1e2d058bf8
Stack:
* #17926 Implement at::has_internal_overlap helper function
* **#17927 Error out on in-place (unary) ops on tensors that have internal overlap**
On the way to #17935.
Works for CPU and CUDA on the following ops:
- abs_, acos_, asin_, atan_, ceil_, cos_, erf_, erfc_, exp_, expm1_
- floor_, log_, log10_, log1p_, log2_, round_, rsqrt_,
- sin_, sqrt_, tan_, tanh_, trunc_
This PR adds a check to see if the out/result tensor has internal
overlap. If it does, then we error out because the result **may** be
incorrect.
This is overly conservative; there are some cases where if the result is
the same as the input, the inplace operation is OK (such as floor_,
round_, and trunc_). However, the current code isn't organized in such a
way that this is easy to check, so enabling those will come in the future.
Reviewed By: ezyang
Differential Revision: D14438871
fbshipit-source-id: 15e12bf1fdb2ab7f74bb806e22bc74840bd6abd1
