bpo-45976: Remove unhelpful locals in Random._randbelow() #29911
Conversation
_randbelow_with_getrandbits() calls getrandbits() at most twice on average, so the local reference never pays for itself. Speeds up randrange(), shuffle(), and sample(). _randbelow_without_getrandbits() gets a similar change for similar reasons.
|
Hello, and thanks for your contribution! I'm a bot set up to make sure that the project can legally accept this contribution by verifying everyone involved has signed the PSF contributor agreement (CLA). Recognized GitHub usernameWe couldn't find a bugs.python.org (b.p.o) account corresponding to the following GitHub usernames: This might be simply due to a missing "GitHub Name" entry in one's b.p.o account settings. This is necessary for legal reasons before we can look at this contribution. Please follow the steps outlined in the CPython devguide to rectify this issue. You can check yourself to see if the CLA has been received. Thanks again for the contribution, we look forward to reviewing it! |
|
Please sign the CLA and continue to update this PR. I'll review it again when Python 3.11 is more mature, so we can have reliable before/after timings. |
|
I think I've done what is necessary to sign the CLA and will check back on it in a few days. |
|
This PR is stale because it has been open for 30 days with no activity. |
|
This issue has been dormant for quite some time but I find it very unlikely that I would have posted an obviously broken test file. Are you using Python 3.10 or current main branch, as it says in the comment? |
|
I would also note that if you find |
|
Marking this as closed. For the average case, it is mildly beneficial but only on some builds. For the multiple rejection case it is detrimental. I prefer to minimize the cost of the unhappy case. |
_randbelow_with_getrandbits() calls getrandbits() at most twice on average, so
the local reference never pays for itself. Speeds up randrange(), shuffle(),
and sample().
_randbelow_without_getrandbits() gets a similar change for similar reasons.
https://bugs.python.org/issue45976