large_enums mir pass: fix is_enabled logic

[RalfJung]

This logic got turned from a guard in run_pass to an is_enabled check in 15d4728#r2989096960, but that was done incorrectly. The pass must never be enabled without unsound_mir_opts!

[rustbot]

Some changes occurred to MIR optimizations

cc @rust-lang/wg-mir-opt

[rustbot]

r? @mati865

rustbot has assigned @mati865.
They will have a look at your PR within the next two weeks and either review your PR or reassign to another reviewer.

Use r? to explicitly pick a reviewer

Why was this reviewer chosen?

The reviewer was selected based on:

• Owners of files modified in this PR: compiler, mir, mir-opt
• compiler, mir, mir-opt expanded to 69 candidates
• Random selection from 12 candidates

[wesleywiser]

@bors r+ rollup

[rust-bors]

📌 Commit 492a1c4 has been approved by wesleywiser

It is now in the queue for this repository.

[RalfJung]

@bors r-
actually let me open an issue for this unsoundness and reference it from the code, while we're at it

[rust-bors]

This pull request was unapproved.

This PR was contained in a rollup (#154411), which was unapproved.

[RalfJung]

Added a link to #154413

@bors r=wesleywiser

[rust-bors]

📌 Commit 298c251 has been approved by wesleywiser

It is now in the queue for this repository.

[rust-bors]

☀️ Test successful - CI
Approved by: wesleywiser
Duration: 3h 12m 25s
Pushing f58bd5c to main...

[github-actions]

What is this?

This is an experimental post-merge analysis report that shows differences in test outcomes between the merged PR and its parent PR.

Comparing 3a933e5 (parent) -> f58bd5c (this PR)

Test differences

Show 2 test diffs

2 doctest diffs were found. These are ignored, as they are noisy.

Test dashboard

Run

cargo run --manifest-path src/ci/citool/Cargo.toml -- \
    test-dashboard f58bd5cee4ce4a97b03146fa94fc9ba68ddd5f64 --output-dir test-dashboard

And then open test-dashboard/index.html in your browser to see an overview of all executed tests.

Job duration changes

1. x86_64-gnu-miri: 1h 36m -> 1h 19m (-17.8%)
2. x86_64-gnu-gcc: 1h 9m -> 57m 15s (-17.2%)
3. x86_64-rust-for-linux: 52m 5s -> 43m 18s (-16.9%)
4. pr-check-1: 33m 31s -> 28m 10s (-16.0%)
5. dist-i586-gnu-i586-i686-musl: 1h 25m -> 1h 36m (+13.7%)
6. test-various: 2h 6m -> 1h 50m (-12.6%)
7. optional-x86_64-gnu-parallel-frontend: 2h 41m -> 2h 22m (-12.1%)
8. i686-gnu-2: 1h 45m -> 1h 32m (-11.9%)
9. x86_64-gnu-tools: 1h 3m -> 56m 25s (-11.7%)
10. aarch64-gnu-debug: 1h 15m -> 1h 7m (-11.4%)

How to interpret the job duration changes?

Job durations can vary a lot, based on the actual runner instance
that executed the job, system noise, invalidated caches, etc. The table above is provided
mostly for t-infra members, for simpler debugging of potential CI slow-downs.

[rust-timer]

Finished benchmarking commit (f58bd5c): comparison URL.

Overall result: ❌ regressions - no action needed

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

Max RSS (memory usage)

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

Cycles

Results (primary -2.3%)

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)	-2.3%	[-2.3%, -2.3%]	1
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	-2.3%	[-2.3%, -2.3%]	1

Binary size

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

Bootstrap: 484.487s -> 487.239s (0.57%)
Artifact size: 395.09 MiB -> 397.11 MiB (0.51%)