Only add non local items to RustdocEffectiveVisibilities::extern_public

[GuillaumeGomez]

While working on #115480, I was finally able to track down the origin of the bug, still working on the fix (how to determine if a foreign trait is publically exported from the current crate in short), which led me to this small PR. It should only list foreign items and yet we don't check if they're locals before adding them to the map.

I expect a very minimal perf improvement.

r? @notriddle

[GuillaumeGomez]

@bors try @rust-timer queue

[bors]

⌛ Trying commit 9d214fc with merge aa06a90...

[bors]

☀️ Try build successful - checks-actions
Build commit: aa06a90 (aa06a90e8ca50e0cfed6359239dbdd58ddc94239)

[rust-timer]

Finished benchmarking commit (aa06a90): comparison URL.

Overall result: no relevant changes - no action needed

Benchmarking this pull request likely means that it is perf-sensitive, so we're automatically marking it as not fit for rolling up. While you can manually mark this PR as fit for rollup, we strongly recommend not doing so since this PR may lead to changes in compiler perf.

@bors rollup=never
@rustbot label: -S-waiting-on-perf -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%	[2.6%, 2.6%]	1
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	-	-	0

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)	2.5%	[2.0%, 3.8%]	7
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	-	-	0

Binary size

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

Bootstrap: 627.383s -> 625.907s (-0.24%)
Artifact size: 270.83 MiB -> 270.85 MiB (0.01%)

[notriddle]

There was no significant change in perf at all, but since the data structure is supposed to only contain external public reexports, this seems better anyway.

@bors r+ rollup

[bors]

📌 Commit 9d214fc has been approved by notriddle

It is now in the queue for this repository.

[petrochenkov]

How is this possible?
There's an assert in fn lib_embargo_visit_item making sure that local items cannot get into this visitor.
Also there's no test with a reproduction in this PR.
Are you sure you are not misinterpreting something?

[petrochenkov]

@bors r-

[GuillaumeGomez]

I might have indeed. The fact that there is no perf change is proof of that. Good catch @petrochenkov !