bpo-37812: Make the small-int alloc optimization unconditional. #15203
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This optimization was added in 1993 (commit 842d2cc), and we've been running with it ever since. I think at this point it's fair to say that it's no longer experimental. That lets us simplify the code by removing a number of `#ifdef`s. In particular this will help us simplify the usage of CHECK_SMALL_INT.
aeros
reviewed
Aug 10, 2019
| @@ -0,0 +1,6 @@ | |||
| The "small int" optimization is now unconditionally enabled. This | |||
| optimization was introduced in Python 1.0.1, and means that :class:`int` | |||
| values from -5 to 256 are pre-initialized rather than constructed on demand. | |||
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I think it is worthwhile to mention that this range is inclusive. Otherwise, users might assume that the maximum is 255 instead of 256, or that the minimum is -4 instead of -5. I've seen this range most commonly notated with [-5, 257), but I think adding "(inclusive)" after it is probably more appropriate and easy to understand for a news entry.
Suggested change
| values from -5 to 256 are pre-initialized rather than constructed on demand. | |
| values from -5 to 256 (inclusive) are pre-initialized rather than constructed on demand. |
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Sure, thanks. I don't want to make a big deal of the exact numbers because it's not something it makes sense for people to depend on -- but it's a natural question for a reader to be curious about. I made it "-5 through 256", which I think is unambiguous while staying unobtrusive.
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This optimization was added in 1993 (commit 842d2cc), and we've
been running with it ever since. I think at this point it's fair
to say that it's no longer experimental. That lets us simplify
the code by removing a number of
#ifdefs.In particular this will help us simplify the usage of CHECK_SMALL_INT.
https://bugs.python.org/issue37812