Optimise math.ceil for known exact float #108801
Open
+9
−5
Conversation
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This matches a similar optimisation done for math.floor in python#21072 Before: ``` λ ./python.exe -m timeit -r 11 -s 'from math import ceil' -s 'x=3.14' 'ceil(x)' 20000000 loops, best of 11: 13.3 nsec per loop λ ./python.exe -m timeit -r 11 -s 'from math import ceil' -s 'x=0.0' 'ceil(x)' 20000000 loops, best of 11: 13.3 nsec per loop λ ./python.exe -m timeit -r 11 -s 'from math import ceil' -s 'x=-3.14E32' 'ceil(x)' 10000000 loops, best of 11: 35.3 nsec per loop λ ./python.exe -m timeit -r 11 -s 'from math import ceil' -s 'x=-323452345.14' 'ceil(x)' 10000000 loops, best of 11: 21.8 nsec per loop ``` After: ``` λ ./python.exe -m timeit -r 11 -s 'from math import ceil' -s 'x=3.14' 'ceil(x)' 20000000 loops, best of 11: 11.8 nsec per loop λ ./python.exe -m timeit -r 11 -s 'from math import ceil' -s 'x=0.0' 'ceil(x)' 20000000 loops, best of 11: 11.7 nsec per loop λ ./python.exe -m timeit -r 11 -s 'from math import ceil' -s 'x=-3.14E32' 'ceil(x)' 10000000 loops, best of 11: 32.7 nsec per loop λ ./python.exe -m timeit -r 11 -s 'from math import ceil' -s 'x=-323452345.14' 'ceil(x)' 10000000 loops, best of 11: 20.1 nsec per loop ```
skirpichev
reviewed
Sep 2, 2023
| @@ -1136,11 +1141,10 @@ math_ceil(PyObject *module, PyObject *number) | |||
| } | |||
| if (PyErr_Occurred()) | |||
| return NULL; | |||
| x = PyFloat_AsDouble(number); | |||
| if (x == -1.0 && PyErr_Occurred()) | |||
There was a problem hiding this comment.
This will be partially covered by tests.
skirpichev
reviewed
Sep 2, 2023
| if (PyFloat_CheckExact(number)) { | ||
| x = PyFloat_AS_DOUBLE(number); | ||
| } | ||
| else |
There was a problem hiding this comment.
Maybe we should follow to the PEP 7 here?
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
This matches a similar optimisation done by rhettinger for math.floor in #21072
Before:
After: