Preserve caches in a call to shrink_to_fit

[tmiasko]

A small follow up to #142542.

[rustbot]

r? @davidtwco

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[rustbot]

Some changes occurred to MIR optimizations

cc @rust-lang/wg-mir-opt

[oli-obk]

@bors try @rust-timer queue

[bors]

⌛ Trying commit 8e266d9 with merge 727e41c...

[bors]

☀️ Try build successful - checks-actions
Build commit: 727e41c (727e41c33fc009ee06a8772ab70f61754bf486ec)

[rust-timer]

Finished benchmarking commit (727e41c): comparison URL.

Overall result: ✅ improvements - 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
Improvements ✅ (primary)	-1.2%	[-1.2%, -1.2%]	1
Improvements ✅ (secondary)	-1.1%	[-1.1%, -1.1%]	1
All ❌✅ (primary)	-1.2%	[-1.2%, -1.2%]	1

Max RSS (memory usage)

Results (primary -2.0%, secondary -0.6%)

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)	2.7%	[2.7%, 2.7%]	1
Improvements ✅ (primary)	-2.0%	[-2.0%, -2.0%]	1
Improvements ✅ (secondary)	-3.9%	[-3.9%, -3.9%]	1
All ❌✅ (primary)	-2.0%	[-2.0%, -2.0%]	1

Cycles

Results (primary 1.0%)

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

	mean	range	count
Regressions ❌ (primary)	1.0%	[0.8%, 1.1%]	5
Regressions ❌ (secondary)	-	-	0
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	1.0%	[0.8%, 1.1%]	5

Binary size

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

Bootstrap: 693.627s -> 697.572s (0.57%)
Artifact size: 371.96 MiB -> 371.98 MiB (0.01%)

[oli-obk]

@bors r+

[bors]

📌 Commit 8e266d9 has been approved by oli-obk

It is now in the queue for this repository.