ConstProp into PlaceElem::Index.

[cjgillot]

Noticed this while looking at keccak output MIR.

This pass aims to replace ProjectionElem::Index with ProjectionElem::ConstantIndex during ConstProp.

r? @ghost

[cjgillot]

@bors try @rust-timer queue

[bors]

⌛ Trying commit 10671a7b859088c0cba078652570ce1b8b740147 with merge f4d49aba595b08dd6a22dd2dadfa119665ec2a41...

[bors]

☀️ Try build successful - checks-actions
Build commit: f4d49aba595b08dd6a22dd2dadfa119665ec2a41 (f4d49aba595b08dd6a22dd2dadfa119665ec2a41)

[rust-timer]

Finished benchmarking commit (f4d49aba595b08dd6a22dd2dadfa119665ec2a41): comparison URL.

Overall result: ✅ improvements - 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
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-7.2%	[-7.2%, -7.2%]	1
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%	[2.7%, 3.5%]	2
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-3.4%	[-3.4%, -3.4%]	1
All ❌✅ (primary)	-	-	0

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
Regressions ❌ (secondary)	-	-	0
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-4.1%	[-5.6%, -2.5%]	2
All ❌✅ (primary)	-	-	0

[rustbot]

Some changes occurred to MIR optimizations

cc @rust-lang/wg-mir-opt

[cjgillot]

r? wg-mir-opt

[oli-obk]

@bors r=JakobDegen,oli-obk

[bors]

📌 Commit a898851 has been approved by JakobDegen,oli-obk

It is now in the queue for this repository.

[bors]

⌛ Testing commit a898851 with merge a0111af...

[bors]

☀️ Test successful - checks-actions
Approved by: JakobDegen,oli-obk
Pushing a0111af to master...

[rust-timer]

Finished benchmarking commit (a0111af): comparison URL.

Overall result: ❌✅ regressions and improvements - 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
Regressions ❌ (secondary)	2.2%	[2.2%, 2.2%]	1
Improvements ✅ (primary)	-0.9%	[-0.9%, -0.9%]	1
Improvements ✅ (secondary)	-7.1%	[-7.1%, -7.1%]	1
All ❌✅ (primary)	-0.9%	[-0.9%, -0.9%]	1

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)	-	-	0
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-3.7%	[-3.7%, -3.7%]	1
All ❌✅ (primary)	-	-	0

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
Regressions ❌ (secondary)	3.0%	[3.0%, 3.0%]	1
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-5.2%	[-5.2%, -5.2%]	1
All ❌✅ (primary)	-	-	0

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
Regressions ❌ (secondary)	-	-	0
Improvements ✅ (primary)	-0.1%	[-0.2%, -0.0%]	8
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	-0.1%	[-0.2%, -0.0%]	8

Bootstrap: 654.215s -> 656.767s (0.39%)

[nnethercote]

This is fine.

@rustbot label: +perf-regression-triaged