signed strict division: just use normal division

[RalfJung]

For some reason, #116090 picked an unnecessarily complicated implementation for this. I don't know if there was any specific reason for this;. Cc @rmehri01 @m-ou-se in case someone remembers.

This was pointed out on IRLO: https://internals.rust-lang.org/t/why-is-strict-div-implemented-in-terms-of-overflowing-div-for-signed-integers/24387

Let's just use regular division here, which is consistent with what we do for unsigned types.

[rustbot]

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[jhpratt]

r=me if there's no concerns. My suspicion is that this was written with #[rustc_inherit_overflow_checks] in mind even though it's not present here.

r? jhpratt

[scottmcm]

The only thing that comes to mind is if someone was wanting it to panic for x / 0 but have overflow behaviour for INT_MIN / -1 -- but of course that's not how our division works today.

[RalfJung]

The only thing that comes to mind is if someone was wanting it to panic for x / 0 but have overflow behaviour for INT_MIN / -1 -- but of course that's not how our division works today.

That exists, it is called overflowing_div.

[jhpratt]

I meant if it existed on the strict function, which it definitely doesn't.

[rustbot]

This PR was rebased onto a different main commit. Here's a range-diff highlighting what actually changed.

Rebasing is a normal part of keeping PRs up to date, so no action is needed—this note is just to help reviewers.