Re: [PATCH v2 1/2] minmax: Add in_range_inclusive() for inclusive range checks
Andy Shevchenko <[email protected]>
| Newsgroups | org.kernel.vger.linux-iio,org.kernel.vger.linux-kernel |
|---|---|
| Organization | Intel Finland Oy - BIC 0357606-4 - c/o Alberga Business Park, 6 krs, Bertel Jungin Aukio 5, 02600 Espoo |
| Message-ID | <[email protected]> |
On Sun, Aug 16, 2026 at 12:26:20PM -0700, Guru Das Srinagesh wrote: > in_range(val, start, len) takes a start and a length, i.e. a half-open > range. Callers that instead have an inclusive [start, end] bound have > no ready helper to reach for and either hand-roll the comparison or > convert it to in_range()'s (start, len) form themselves. > > Add in_range_inclusive(val, start, end) as a direct comparison rather > than a wrapper around in_range(): computing len as end - start + 1 and > forwarding it to in_range() subverts in_range()'s 32-bit/64-bit dispatch > for sub-32-bit types via integer promotion, and overflows to 0 when @end > is the type's maximum value, silently rejecting every input instead of > accepting all of them. > > val, start and end are each assigned to a __UNIQUE_ID()-generated > temporary before use, matching the __cmp_once()/__cmp_once_unique() > pattern: each argument is evaluated exactly once, and the temporary > can't be shadowed by a caller's own same-named local variable. No new code to lib/ without test cases. NAK (until the test cases are not provided). ... > +/** > + * in_range_inclusive - Determine if a value lies within an inclusive range. > + * @val: Value to test. > + * @start: First value in range. > + * @end: Last value in range. > + * > + * @val, @start and @end are each evaluated exactly once. This misses the return section (yes, this is not obvious, but needs to add it) > + */ > +#define in_range_inclusive(val, start, end) \ > + __in_range_inclusive(val, start, end, __UNIQUE_ID(val_), \ > + __UNIQUE_ID(start_), __UNIQUE_ID(end_)) Do you know what __UNIQUE_ID() does and how it will affect the preprocessed size? It may or may not be needed depending on the (current) use cases. -- With Best Regards, Andy Shevchenko