Remove len argument from RawVec::reserve_for_push

[caibear]

Removes RawVec::reserve_for_push's len argument since it's always the same as capacity.
Also makes Vec::insert use RawVec::reserve_for_push.

[rustbot]

Thanks for the pull request, and welcome! The Rust team is excited to review your changes, and you should hear from @cuviper (or someone else) some time within the next two weeks.

Please see the contribution instructions for more information. Namely, in order to ensure the minimum review times lag, PR authors and assigned reviewers should ensure that the review label (S-waiting-on-review and S-waiting-on-author) stays updated, invoking these commands when appropriate:

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[bors]

☔ The latest upstream changes (presumably #122396) made this pull request unmergeable. Please resolve the merge conflicts.

[cuviper]

Also makes Vec::insert use RawVec::reserve_for_push.

Maybe we should rename to reserve_one?

Anyway, this needs a rebase after #122396.
@rustbot author

[caibear]

Maybe we should rename to reserve_one?

reserve_one sounds like an specialized version of reserve(1). Unlike reserve(1), it always grows. I think a name like grow_one
more accurately represents it.

[caibear]

@rustbot review

[cuviper]

That looks fine to me!

@bors r+

[bors]

📌 Commit aba592d has been approved by cuviper

It is now in the queue for this repository.

[bors]

⌛ Testing commit aba592d with merge ca8923a...

[bors]

💔 Test failed - checks-actions

[cuviper]

That's a legitimate failure, but it should be a straightforward update of the expected strings.
@rustbot author

[caibear]

@rustbot review

[cuviper]

@bors r+

[bors]

📌 Commit 4500c83 has been approved by cuviper

It is now in the queue for this repository.

[bors]

⌛ Testing commit 4500c83 with merge 877d36b...

[bors]

☀️ Test successful - checks-actions
Approved by: cuviper
Pushing 877d36b to master...

[rust-timer]

Finished benchmarking commit (877d36b): comparison URL.

Overall result: ❌✅ regressions and improvements - ACTION NEEDED

Next Steps: If you can justify the regressions found in this perf run, please indicate this with @rustbot label: +perf-regression-triaged along with sufficient written justification. If you cannot justify the regressions please open an issue or create a new PR that fixes the regressions, add a comment linking to the newly created issue or PR, and then add the perf-regression-triaged label to this PR.

@rustbot label: +perf-regression
cc @rust-lang/wg-compiler-performance

Instruction count

This is a highly reliable metric that was used to determine the overall result at the top of this comment.

	mean	range	count
Regressions ❌ (primary)	-	-	0
Regressions ❌ (secondary)	2.8%	[2.8%, 2.8%]	1
Improvements ✅ (primary)	-1.7%	[-1.7%, -1.7%]	1
Improvements ✅ (secondary)	-0.4%	[-0.4%, -0.3%]	5
All ❌✅ (primary)	-1.7%	[-1.7%, -1.7%]	1

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)	-	-	0
Improvements ✅ (primary)	-2.8%	[-3.6%, -1.9%]	2
Improvements ✅ (secondary)	-2.8%	[-3.1%, -2.5%]	2
All ❌✅ (primary)	-2.8%	[-3.6%, -1.9%]	2

Cycles

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)	2.1%	[2.1%, 2.1%]	1
Improvements ✅ (primary)	-1.2%	[-1.5%, -1.0%]	3
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	-1.2%	[-1.5%, -1.0%]	3

Binary size

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)	0.1%	[0.1%, 0.2%]	2
Regressions ❌ (secondary)	-	-	0
Improvements ✅ (primary)	-0.0%	[-0.2%, -0.0%]	33
Improvements ✅ (secondary)	-0.0%	[-0.2%, -0.0%]	38
All ❌✅ (primary)	-0.0%	[-0.2%, 0.2%]	35

Bootstrap: 668.236s -> 671.487s (0.49%)
Artifact size: 315.84 MiB -> 315.77 MiB (-0.02%)