Compute information about function parameters on THIR

[cjgillot]

This avoids some manipulation of typeck results while building MIR.

[rust-highfive]

r? @oli-obk

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[bors]

☔ The latest upstream changes (presumably #101143) made this pull request unmergeable. Please resolve the merge conflicts.

[oli-obk]

Please bless the ui test changes so they are easier to review

@rustbot author

[oli-obk]

This is odd, I would have assumed the changes to cause the opposite diff

[cjgillot]

We replace def_span by span_with_body for closures, so span is longer except in specially addressed cases. As this is a debugging feature, I did not bother to keep the former behaviour.

[oli-obk]

The ui output regression is fine in single line cases, but for multi line closures it's quite bad (and that makes up like 2/3rd of the ui changes. I don't think we should merge this as is. If mitigations can be deployed at diagnostic rendering time that would be fine with me. Since it's all about nll diagnostics, it could be possible to fix the span at borrowck time.

[bors]

☔ The latest upstream changes (presumably #99102) made this pull request unmergeable. Please resolve the merge conflicts.

[oli-obk]

@bors r+

[bors]

📌 Commit 49908191456a14a025e06f10d651e52f8e499a78 has been approved by oli-obk

It is now in the queue for this repository.

[bors]

☔ The latest upstream changes (presumably #101239) made this pull request unmergeable. Please resolve the merge conflicts.

[cjgillot]

@bors r=oli-obk

[bors]

📌 Commit b9e1806 has been approved by oli-obk

It is now in the queue for this repository.

[cjgillot]

@bors r=oli-obk

[bors]

📌 Commit ce9daa2 has been approved by oli-obk

It is now in the queue for this repository.

[bors]

⌛ Testing commit ce9daa2 with merge c84083b...

[bors]

☀️ Test successful - checks-actions
Approved by: oli-obk
Pushing c84083b to master...

[rust-timer]

Finished benchmarking commit (c84083b): 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.

	mean1	range	count2
Regressions ❌ (primary)	0.4%	[0.2%, 0.5%]	10
Regressions ❌ (secondary)	0.6%	[0.3%, 1.6%]	4
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	0.4%	[0.2%, 0.5%]	10

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.

	mean1	range	count2
Regressions ❌ (primary)	2.6%	[2.6%, 2.6%]	1
Regressions ❌ (secondary)	1.6%	[0.8%, 2.4%]	2
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-1.4%	[-1.4%, -1.4%]	3
All ❌✅ (primary)	2.6%	[2.6%, 2.6%]	1

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.

	mean1	range	count2
Regressions ❌ (primary)	2.2%	[1.5%, 3.0%]	2
Regressions ❌ (secondary)	4.1%	[4.1%, 4.1%]	1
Improvements ✅ (primary)	-1.7%	[-1.7%, -1.7%]	1
Improvements ✅ (secondary)	-4.2%	[-4.2%, -4.2%]	1
All ❌✅ (primary)	0.9%	[-1.7%, 3.0%]	3

Footnotes

1. the arithmetic mean of the percent change ↩ ↩² ↩³

2. number of relevant changes ↩ ↩² ↩³

[pnkfelix]

• between 0.38% and 0.47% regression for stm32f4 in various incremental scenarios. Approximately 0.25% on serde,clap,image for incremental.
• it seems plausible that this is just overhead that we have to pay, in terms of adding more state to the THIR, in exchange for simpler MIR construction code.
• (its also possible that this is just noise, though the listed benchmarks are not the same as the other ones that have been exhibiting bimodality this last week.)
• marking as triaged.

@rustbot label: perf-regression-triaged

[nnethercote]

I strongly suspect these changes are not noise.