Stabilize nonzero_bits

[nvzqz]

Closes#94881, implemented by #93292.

This change stabilizes the associated BITS constant for NonZero{U,I}{8,16,32,64,128,size} integers, e.g.:

implNonZeroUsize{pubconstBITS:u32 = usize::BITS;}

[rustbot]

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[rust-highfive]

r? @joshtriplett

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[joshtriplett]

This seems low-risk. These match the corresponding values on the non-nonzero integer types, and don't have any special considerations for nonzero-ness.

@rfcbot merge

[rfcbot]

Team member @joshtriplett has proposed to merge this. The next step is review by the rest of the tagged team members:

• @Amanieu
• @BurntSushi
• @dtolnay
• @joshtriplett
• @m-ou-se
• @yaahc

No concerns currently listed.

Once a majority of reviewers approve (and at most 2 approvals are outstanding), this will enter its final comment period. If you spot a major issue that hasn't been raised at any point in this process, please speak up!

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[rfcbot]

🔔 This is now entering its final comment period, as per the review above. 🔔

[rfcbot]

The final comment period, with a disposition to merge, as per the review above, is now complete.

As the automated representative of the governance process, I would like to thank the author for their work and everyone else who contributed.

This will be merged soon.

[thomcc]

This finished the FCP in favor a while ago, so it can be merged.

@bors r+

[bors]

📌 Commit db57653 has been approved by thomcc

It is now in the queue for this repository.

[bors]

⌛ Testing commit db57653 with merge 9e77211...

[bors]

☀️ Test successful - checks-actions
Approved by: thomcc
Pushing 9e77211 to master...

[rust-timer]

Finished benchmarking commit (9e77211): comparison URL.

Overall result: no relevant changes - no action needed

@rustbot label: -perf-regression

Instruction count

This benchmark run did not return any relevant results for this metric.

Max RSS (memory usage)

Results

This is a less reliable metric that may be of interest but was not used to determine the overall result at the top of this comment.

	mean	range	count
Regressions ❌ (primary)	-	-	0
Regressions ❌ (secondary)	2.6%	[2.1%, 3.1%]	2
Improvements ✅ (primary)	-3.8%	[-3.8%, -3.8%]	1
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	-3.8%	[-3.8%, -3.8%]	1

Cycles

This benchmark run did not return any relevant results for this metric.