Inline Poll methods

[EFanZh]

With opt-level="z", the Poll::map* methods are sometimes not inlined (see https://godbolt.org/z/ca5ajKTEK). This PR adds #[inline] to these methods. I have a project that can benefit from this change, but do we want to enable this behavior universally?

Fixes #101080.

[rustbot]

r? @Mark-Simulacrum

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[eggyal]

Seems reasonable to me: it's consistent with guidance at https://std-dev-guide.rust-lang.org/code-considerations/performance/inline.html (modulo genericness, though the map_* methods on Option and Result are also #[inline] and this isn't really any different, plus it does indeed change the inlining behaviour as per the raised issue).

[Mark-Simulacrum]

@bors r+

[bors]

📌 Commit 4bb0a5e has been approved by Mark-Simulacrum

It is now in the queue for this repository.

[bors]

⌛ Testing commit 4bb0a5e with merge 31f858d...

[bors]

☀️ Test successful - checks-actions
Approved by: Mark-Simulacrum
Pushing 31f858d to master...

[rust-timer]

Finished benchmarking commit (31f858d): 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)	-	-	0
Improvements ✅ (primary)	-3.1%	[-3.2%, -2.9%]	2
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	-3.1%	[-3.2%, -2.9%]	2

Cycles

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