Introduce PlaceContext::may_observe_address.

[cjgillot]

A small utility method to avoid open-coding the logic in several MIR opts.

[rustbot]

r? @saethlin

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[rustbot]

Some changes occurred to MIR optimizations

cc @rust-lang/wg-mir-opt

[saethlin]

@bors r+ rollup

Nice.

[bors]

📌 Commit 4e7a068 has been approved by saethlin

It is now in the queue for this repository.

[matthiaskrgr]

@rust-timer build 771aa30

[rust-timer]

Finished benchmarking commit (771aa30): comparison URL.

Overall result: ❌✅ regressions and improvements - please read the text below

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.

Next Steps: If you can justify the regressions found in this try perf run, please do so in sufficient writing along with @rustbot label: +perf-regression-triaged. If not, please fix the regressions and do another perf run. If its results are neutral or positive, the label will be automatically removed.

@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)	0.3%	[0.1%, 0.4%]	8
Regressions ❌ (secondary)	0.4%	[0.1%, 0.9%]	11
Improvements ✅ (primary)	-0.2%	[-0.2%, -0.2%]	1
Improvements ✅ (secondary)	-2.7%	[-2.9%, -2.5%]	6
All ❌✅ (primary)	0.2%	[-0.2%, 0.4%]	9

Max RSS (memory usage)

Results (primary -0.3%, secondary 1.5%)

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

	mean	range	count
Regressions ❌ (primary)	1.7%	[1.4%, 2.0%]	2
Regressions ❌ (secondary)	1.5%	[0.8%, 2.3%]	3
Improvements ✅ (primary)	-2.3%	[-3.1%, -1.5%]	2
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	-0.3%	[-3.1%, 2.0%]	4

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: 467.642s -> 466.96s (-0.15%)
Artifact size: 387.46 MiB -> 387.46 MiB (-0.00%)

[panstromek]

perf triage:

Based on the build above, this seems to have caused a perf regression in #146304, which feels a bit surprising. Especially since detailed results indicate large increases in some query execution counts. @cjgillot is this expected, shuold we do something about it?

Edit: detailed results for diesel debug here