Disable two mir opts that are known to be unsound

[oli-obk]

closes #112460 (does not fix the underlying issue)

r? @cjgillot

[rustbot]

Thanks for the pull request, and welcome! The Rust team is excited to review your changes, and you should hear from @cjgillot (or someone else) soon.

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[rustbot]

Some changes occurred to MIR optimizations

cc @rust-lang/wg-mir-opt

[cjgillot]

That's the safest solution indeed.
@bors r+ rollup=never

There is likely a perf effect, which reverses the one from #112040

[bors]

📌 Commit 8a482b37249f2d4d48c13fbc68eb8f26666190d5 has been approved by cjgillot

It is now in the queue for this repository.

[RalfJung]

Would be good to link to some form of explanation of what is unsound here.

[oli-obk]

@bors r=cjgillot

[bors]

📌 Commit 346078eb210462f34e95e4f8333c827ebf9a43be has been approved by cjgillot

It is now in the queue for this repository.

[bors]

⌛ Testing commit 346078eb210462f34e95e4f8333c827ebf9a43be with merge 8e9e75dfca891216eb4b90b49e750f3122cc7e9d...

[bors]

💔 Test failed - checks-actions

[oli-obk]

@bors r=cjgillot

[bors]

📌 Commit c409f05 has been approved by cjgillot

It is now in the queue for this repository.

[bors]

⌛ Testing commit c409f05 with merge 38b44eb...

[bors]

☀️ Test successful - checks-actions
Approved by: cjgillot
Pushing 38b44eb to master...

[rust-timer]

Finished benchmarking commit (38b44eb): comparison URL.

Overall result: ❌ regressions - ACTION NEEDED

Next Steps: If you can justify the regressions found in this perf run, please indicate this with @rustbot label: +perf-regression-triaged along with sufficient written justification. If you cannot justify the regressions please open an issue or create a new PR that fixes the regressions, add a comment linking to the newly created issue or PR, and then add the perf-regression-triaged label to this PR.

@rustbot label: +perf-regression
cc @rust-lang/wg-compiler-performance

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)	0.4%	[0.3%, 0.9%]	48
Regressions ❌ (secondary)	0.5%	[0.2%, 1.1%]	30
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-0.2%	[-0.3%, -0.1%]	2
All ❌✅ (primary)	0.4%	[0.3%, 0.9%]	48

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)	1.8%	[0.6%, 2.9%]	3
Regressions ❌ (secondary)	-	-	0
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	1.8%	[0.6%, 2.9%]	3

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)	0.8%	[0.8%, 0.8%]	1
Regressions ❌ (secondary)	2.1%	[2.1%, 2.1%]	1
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	0.8%	[0.8%, 0.8%]	1

Binary size

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)	0.1%	[0.0%, 0.3%]	25
Regressions ❌ (secondary)	0.1%	[0.1%, 0.1%]	3
Improvements ✅ (primary)	-0.1%	[-0.3%, -0.0%]	41
Improvements ✅ (secondary)	-0.1%	[-0.1%, -0.1%]	4
All ❌✅ (primary)	-0.0%	[-0.3%, 0.3%]	66

Bootstrap: 657.151s -> 659.034s (0.29%)

[oli-obk]

This reverts the perf improvements from #112040 to fix a soundness bug

@rustbot label: +perf-regression-triaged