Box AssertKind

[saethlin]

r? @nnethercote this feels like your kind of thing

I want to add a new variant to AssertKind that needs 3 operands, and that ends up breaking a bunch of size assertions. So... what if we go the opposite direction first; shrinking AssertKind by boxing it?

[rustbot]

Some changes occurred to MIR optimizations

cc @rust-lang/wg-mir-opt

This PR changes MIR

cc @oli-obk, @RalfJung, @JakobDegen, @davidtwco, @celinval, @vakaras

[saethlin]

@bors try @rust-timer queue

[bors]

⌛ Trying commit a98aae4adc7a71341d43c451ba81f0b91aa5db48 with merge 30d20dc74f0c284de32ced72fc489cf59e0acd48...

[bors]

☀️ Try build successful - checks-actions
Build commit: 30d20dc74f0c284de32ced72fc489cf59e0acd48 (30d20dc74f0c284de32ced72fc489cf59e0acd48)

[nnethercote]

LGTM, assuming no perf regressions.

@bors delegate=saethlin

[bors]

✌️ @saethlin can now approve this pull request

[rust-timer]

Finished benchmarking commit (30d20dc74f0c284de32ced72fc489cf59e0acd48): comparison URL.

Overall result: ❌ regressions - no action needed

Benchmarking this pull request likely means that it is perf-sensitive, so we're automatically marking it as not fit for rolling up. While you can manually mark this PR as fit for rollup, we strongly recommend not doing so since this PR may lead to changes in compiler perf.

@bors rollup=never
@rustbot label: -S-waiting-on-perf -perf-regression

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
Regressions ❌ (secondary)	0.6%	[0.6%, 0.6%]	1
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	-	-	0

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)	-	-	0
Regressions ❌ (secondary)	3.1%	[3.1%, 3.1%]	1
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-1.1%	[-1.1%, -1.1%]	2
All ❌✅ (primary)	-	-	0

Cycles

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

Binary size

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

Bootstrap: 656.457s -> 656.712s (0.04%)

[rustbot]

Some changes occurred in compiler/rustc_codegen_cranelift

cc @bjorn3

[saethlin]

@bors r+

[bors]

📌 Commit f08f903 has been approved by saethlin

It is now in the queue for this repository.

[bors]

⌛ Testing commit f08f903 with merge 9d795a6...

[bors]

☀️ Test successful - checks-actions
Approved by: saethlin
Pushing 9d795a6 to master...

[rust-timer]

Finished benchmarking commit (9d795a6): comparison URL.

Overall result: ❌ regressions - no action needed

@rustbot label: -perf-regression

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
Regressions ❌ (secondary)	0.5%	[0.5%, 0.5%]	1
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	-	-	0

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)	-	-	0
Regressions ❌ (secondary)	2.1%	[0.9%, 3.3%]	2
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	-	-	0

Cycles

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

Binary size

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

Bootstrap: 656.873s -> 656.624s (-0.04%)

[saethlin]

Hunh. I dismissed the regression as noise initially, but seeing it in 2 runs means it's much more likely to be real and significant.

I suspect the reason we see this is that keccak is like a stress test of checked slice (or is it array?) indexing. It probably has way more panic paths than any normal program. Good to be aware of this though.