Remove one loop in extract_cfg_from_attrs

[GuillaumeGomez]

Follow-up of #138907.

r? lolbinarycat

[GuillaumeGomez]

@bors try @rust-timer queue

[lolbinarycat]

code is sound, as Attribute::ident always returns None for Attribute::Parsed, so there is no case where both branches would have run and now only one runs.

one question about a comment, otherwise lgtm.

View changes since this review

[lolbinarycat]

does this comment still make sense?

[rust-bors]

☀️ Try build successful (CI)
Build commit: 7b3f411 (7b3f4110d6faa0cbf30b4d01ad4d4f43c3b677e1, parent: c8905eaa66e0c35a33626e974b9ce6955c739b5b)

[rust-timer]

Finished benchmarking commit (7b3f411): comparison URL.

Overall result: ❌ regressions - no action needed

Benchmarking this pull request means it may be perf-sensitive – we'll automatically label it not fit for rolling up. You can override this, but we strongly advise not to, due to possible changes in compiler perf.

@bors rollup=never
@rustbot label: -S-waiting-on-perf -perf-regression

Instruction count

Our most reliable metric. Used to determine the overall result above. However, even this metric can be noisy.

	mean	range	count
Regressions ❌ (primary)	-	-	0
Regressions ❌ (secondary)	0.0%	[0.0%, 0.0%]	1
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	-	-	0

Max RSS (memory usage)

Results (primary -0.5%)

A less reliable metric. May be of interest, but not used to determine the overall result above.

	mean	range	count
Regressions ❌ (primary)	2.7%	[2.7%, 2.7%]	1
Regressions ❌ (secondary)	-	-	0
Improvements ✅ (primary)	-3.7%	[-3.7%, -3.7%]	1
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	-0.5%	[-3.7%, 2.7%]	2

Cycles

Results (secondary 2.8%)

A less reliable metric. May be of interest, but not used to determine the overall result above.

	mean	range	count
Regressions ❌ (primary)	-	-	0
Regressions ❌ (secondary)	2.8%	[2.3%, 3.4%]	3
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	-	-	0

Binary size

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

Bootstrap: 470.874s -> 471.366s (0.10%)
Artifact size: 387.66 MiB -> 387.66 MiB (0.00%)