[WIP] resolve: Concatenate reexport chains from all crates

[petrochenkov]

This is needed for rustdoc, and rustdoc can technically do it by itself, but let's see if doing it in the compiler affects performance or not.

cc #81893

[rustbot]

r? @fee1-dead

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• Owners of files modified in this PR: compiler
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[petrochenkov]

@bors try @rust-timer queue

[rust-bors]

☀️ Try build successful (CI)
Build commit: 5bc7a63 (5bc7a638a2b58f7abb3b412cc48ebc41208dd982)
Base parent: e457a7b (e457a7b0d326d67b4322ef0d11bd715cfaeda48f)

[rust-timer]

Finished benchmarking commit (5bc7a63): comparison URL.

Overall result: ❌✅ regressions and improvements - please read:

Benchmarking means the PR may be perf-sensitive. It's automatically marked not fit for rolling up. Overriding is possible but disadvised: it risks changing compiler perf.

Next, please: If you can, justify the regressions found in this try perf run in writing along with @rustbot label: +perf-regression-triaged. If not, fix the regressions and do another perf run. Neutral or positive results will clear the label automatically.

@bors rollup=never rustc-perf
@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)	0.1%	[0.1%, 0.1%]	1
Regressions ❌ (secondary)	0.2%	[0.1%, 0.2%]	3
Improvements ✅ (primary)	-0.4%	[-0.4%, -0.4%]	1
Improvements ✅ (secondary)	-0.2%	[-0.2%, -0.2%]	3
All ❌✅ (primary)	-0.1%	[-0.4%, 0.1%]	2

Max RSS (memory usage)

Results (primary 1.1%, secondary -0.1%)

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

	mean	range	count
Regressions ❌ (primary)	2.0%	[1.2%, 2.7%]	2
Regressions ❌ (secondary)	3.8%	[1.6%, 8.8%]	7
Improvements ✅ (primary)	-0.7%	[-0.7%, -0.7%]	1
Improvements ✅ (secondary)	-4.1%	[-6.9%, -2.2%]	7
All ❌✅ (primary)	1.1%	[-0.7%, 2.7%]	3

Cycles

Results (primary 0.3%, secondary 3.2%)

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

	mean	range	count
Regressions ❌ (primary)	2.3%	[2.3%, 2.3%]	1
Regressions ❌ (secondary)	3.2%	[2.0%, 4.5%]	2
Improvements ✅ (primary)	-1.7%	[-1.7%, -1.7%]	1
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	0.3%	[-1.7%, 2.3%]	2

Binary size

Results (secondary -0.0%)

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

Bootstrap: 476.343s -> 476.199s (-0.03%)
Artifact size: 402.74 MiB -> 402.76 MiB (0.01%)