Utilize std::make_unsigned_t instead of wrapping lshift #35323
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Currently lshift_kernel uses a hacky wrapper that wraps all integer types. This is unnecessary because we have std::make_unsigned_t [ghstack-poisoned]
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💊 CircleCI build failures summary and remediationsAs of commit dc94be3 (more details on the Dr. CI page): 💚 💚 Looks good so far! There are no CircleCI failures yet. 💚 💚 This comment was automatically generated by Dr. CI (expand for details).Follow this link to opt-out of these comments for your Pull Requests.Please report bugs/suggestions on the GitHub issue tracker. This comment has been revised 8 times. |
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Currently lshift_kernel uses a hacky wrapper that wraps all integer types. This is unnecessary because we have std::make_unsigned_t [ghstack-poisoned]
XiaobingSuper
approved these changes
Mar 25, 2020
zou3519
reviewed
Mar 25, 2020
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| static inline int64_t lshift_wrapper(int64_t a, int64_t b) { | ||
| return ((uint64_t)a) << b; |
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Just out of curiosity, why do we have to make the left hand side unsigned before performing the shift?
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Probably because shifting on signed integers in C++ is implementation defined. See https://stackoverflow.com/a/4009954/1150462 for an explanation and reference.
Currently lshift_kernel uses a hacky wrapper that wraps all integer types. This is unnecessary because we have std::make_unsigned_t [ghstack-poisoned]
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Weird, this has actually been merged in beac3f2 . Manually closing now. |
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Stack from ghstack:
Currently lshift_kernel uses a hacky wrapper that wraps all integer
types. This is unnecessary because we have std::make_unsigned_t
Differential Revision: D20824641