borrowck: Simplify deps to build compiler 30s faster

[joshtriplett]

rustc_borrowck uses two helpers from rustc_traits. One of them is re-exported from rustc_trait_selection, and the other can easily move to rustc_trait_selection.

Making rustc_borrowck use these helpers from rustc_trait_selection directly, and eliminating the rustc_traits dependency, allows starting to build rustc_borrowck earlier, which substantially speeds up building the compiler because rustc_borrowck is one of the last things to build.

On my system, this speeds up the rustc build by a little over 30s.

[rustbot]

r? @TaKO8Ki

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[rustbot]

These commits modify the Cargo.lock file. Unintentional changes to Cargo.lock can be introduced when switching branches and rebasing PRs.

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[mejrs]

@bors try @rust-timer queue

[rust-bors]

☀️ Try build successful (CI)
Build commit: f1bf412 (f1bf412ba34726c72fd27fb00f7b35c908c57318)
Base parent: 73dc916 (73dc9167f1cd099e525c9ade2e068d1907b78564)

[rust-timer]

Finished benchmarking commit (f1bf412): comparison URL.

Overall result: no relevant changes - no action needed

Benchmarking means the PR may be perf-sensitive. Consider adding rollup=never if this change is not fit for rolling up.

@rustbot label: -S-waiting-on-perf -perf-regression

Instruction count

This perf run didn't have relevant results for this metric.

Max RSS (memory usage)

Results (primary 3.4%, secondary 0.5%)

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

	mean	range	count
Regressions ❌ (primary)	3.4%	[0.5%, 6.4%]	2
Regressions ❌ (secondary)	0.5%	[0.4%, 0.6%]	5
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	3.4%	[0.5%, 6.4%]	2

Cycles

Results (primary 0.1%, secondary -0.4%)

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

	mean	range	count
Regressions ❌ (primary)	0.7%	[0.5%, 1.1%]	5
Regressions ❌ (secondary)	0.7%	[0.5%, 1.0%]	6
Improvements ✅ (primary)	-0.7%	[-0.9%, -0.6%]	4
Improvements ✅ (secondary)	-2.1%	[-2.9%, -1.0%]	4
All ❌✅ (primary)	0.1%	[-0.9%, 1.1%]	9

Binary size

This perf run didn't have relevant results for this metric.

Bootstrap: 490.553s -> 487.967s (-0.53%)
Artifact size: 390.33 MiB -> 390.35 MiB (0.01%)

[joshtriplett]

AIUI, the perf suite bootstrap timing uses -j1, so it isn't picking up on improvements that primarily help builds with higher parallelism. This was a 30s improvement on my system with -j12.

[mejrs]

It'll also be very nice for people making changes to rustc_traits :)

r? me @bors r+

View changes since this review

[rust-bors]

📌 Commit 425c312 has been approved by mejrs

It is now in the queue for this repository.