Remove usage of to_stable_hash_key when stable hashing hash maps

[Kobzol]

I tried to look for some types that had an expensive to_stable_hash_key implementation and move them to HashStable instead. Let's see if there's any perf. impact.

[rustbot]

r? @cjgillot

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[Kobzol]

@bors try @rust-timer queue

[bors]

⌛ Trying commit e219c53 with merge e920371...

[bors]

☀️ Try build successful - checks-actions
Build commit: e920371 (e920371d99e09e26858849d1307758788199d8bd)

[rust-timer]

Finished benchmarking commit (e920371): comparison URL.

Overall result: ✅ improvements - 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 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)	-	-	0
Improvements ✅ (primary)	-0.6%	[-0.6%, -0.6%]	1
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	-0.6%	[-0.6%, -0.6%]	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)	0.4%	[0.4%, 0.4%]	1
Regressions ❌ (secondary)	3.4%	[3.4%, 3.4%]	1
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-1.7%	[-2.2%, -1.1%]	2
All ❌✅ (primary)	0.4%	[0.4%, 0.4%]	1

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)	0.6%	[0.5%, 0.8%]	2
Regressions ❌ (secondary)	-	-	0
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	0.6%	[0.5%, 0.8%]	2

Binary size

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

Bootstrap: 671.862s -> 673.243s (0.21%)
Artifact size: 312.35 MiB -> 312.32 MiB (-0.01%)

[Kobzol]

Hmm, no big effect. And since #119192 will probably remove most remaining usages of hashmaps in stable hashing soon, it's probably not worth it to do this.