Also consider call and yield as MIR SSA.

[cjgillot]

The SSA analysis on MIR only considered Assign statements as defining a SSA local.
This PR adds assignments as part of a Call or Yield terminator in that category.

This mainly allows to perform CopyProp on a call return place.

The only subtlety is in the dominance property: the assignment is only complete at the beginning of the target block.

[rustbot]

r? @fee1-dead

(rustbot has picked a reviewer for you, use r? to override)

[rustbot]

Some changes occurred to MIR optimizations

cc @rust-lang/wg-mir-opt

[cjgillot]

@bors try @rust-timer queue

[bors]

⌛ Trying commit f387190b865b5190e1bed8f99314f8cc47c960f2 with merge 44b37cc929dfd0ae3fd296127954dac5658fa02c...

[bors]

☀️ Try build successful - checks-actions
Build commit: 44b37cc929dfd0ae3fd296127954dac5658fa02c (44b37cc929dfd0ae3fd296127954dac5658fa02c)

[rust-timer]

Finished benchmarking commit (44b37cc929dfd0ae3fd296127954dac5658fa02c): comparison URL.

Overall result: ❌✅ regressions and improvements - 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.

Next Steps: If you can justify the regressions found in this try perf run, please indicate this with @rustbot label: +perf-regression-triaged along with sufficient written justification. If you cannot justify the regressions please fix the regressions and do another perf run. If the next run shows neutral or positive results, the label will be automatically removed.

@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)	1.2%	[1.2%, 1.2%]	1
Regressions ❌ (secondary)	-	-	0
Improvements ✅ (primary)	-0.6%	[-1.1%, -0.4%]	5
Improvements ✅ (secondary)	-0.6%	[-0.8%, -0.4%]	10
All ❌✅ (primary)	-0.3%	[-1.1%, 1.2%]	6

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)	4.8%	[3.9%, 5.7%]	2
Regressions ❌ (secondary)	3.6%	[3.2%, 4.0%]	2
Improvements ✅ (primary)	-3.0%	[-3.3%, -2.7%]	2
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	0.9%	[-3.3%, 5.7%]	4

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)	3.7%	[1.9%, 4.7%]	7
Regressions ❌ (secondary)	-	-	0
Improvements ✅ (primary)	-1.5%	[-1.5%, -1.5%]	1
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	3.0%	[-1.5%, 4.7%]	8

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)	0.3%	[0.0%, 0.8%]	5
Regressions ❌ (secondary)	0.2%	[0.2%, 0.2%]	1
Improvements ✅ (primary)	-0.3%	[-1.7%, -0.0%]	92
Improvements ✅ (secondary)	-0.3%	[-1.2%, -0.0%]	18
All ❌✅ (primary)	-0.3%	[-1.7%, 0.8%]	97

Bootstrap: 651.291s -> 650.54s (-0.12%)

[fee1-dead]

Not familiar with this.

r? compiler

[cjgillot]

r? wg-mir-opt

[cjgillot]

r? compiler

[bors]

☔ The latest upstream changes (presumably #116183) made this pull request unmergeable. Please resolve the merge conflicts.

[cjgillot]

@tmiasko Following the discussion on #116454 (comment), I reuse DefLocation::Body for the terminators. Do you agree with this conclusion?

[tmiasko]

I tried fixing the handling of call terminators in DefLocation::dominates and in retrospect your earlier approach with an additional variant turned out much simpler (reusing DefLocation::Body requires DefLocation::dominates to access basic blocks and that gets quite inconvenient). Thus, I would propose something along the lines of abd4ad1.

I am not sure if you are still planning to address this as part of this pull request or not. Either way seems fine to me, including leaving DefLocation::Body as is.

[cjgillot]

So let's go small steps. This PR as-is, then abd4ad1 in a second PR.

[tmiasko]

@bors r+

[bors]

📌 Commit 37f080e has been approved by tmiasko

It is now in the queue for this repository.

[bors]

⌛ Testing commit 37f080e with merge d627cf0...

[bors]

☀️ Test successful - checks-actions
Approved by: tmiasko
Pushing d627cf0 to master...

[rust-timer]

Finished benchmarking commit (d627cf0): 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)	3.9%	[3.9%, 3.9%]	1
Regressions ❌ (secondary)	0.1%	[0.1%, 0.1%]	2
Improvements ✅ (primary)	-0.4%	[-0.9%, -0.2%]	26
Improvements ✅ (secondary)	-0.4%	[-0.6%, -0.3%]	5
All ❌✅ (primary)	-0.2%	[-0.9%, 3.9%]	27

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)	5.3%	[5.1%, 5.5%]	2
Regressions ❌ (secondary)	-	-	0
Improvements ✅ (primary)	-3.5%	[-6.0%, -1.1%]	7
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	-1.6%	[-6.0%, 5.5%]	9

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)	3.2%	[3.2%, 3.2%]	1
Regressions ❌ (secondary)	-	-	0
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	3.2%	[3.2%, 3.2%]	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)	0.2%	[0.0%, 0.4%]	16
Regressions ❌ (secondary)	-	-	0
Improvements ✅ (primary)	-0.4%	[-1.8%, -0.0%]	72
Improvements ✅ (secondary)	-0.3%	[-1.3%, -0.0%]	19
All ❌✅ (primary)	-0.3%	[-1.8%, 0.4%]	88

Bootstrap: 626.852s -> 628.751s (0.30%)
Artifact size: 270.87 MiB -> 270.76 MiB (-0.04%)

[nnethercote]

icounts/cycles/wall-time/max-rss are a wash, but binary size and artifact size see some small but clear improvements.

@rustbot label: +perf-regression-triaged