[PERF CHECK ONLY] Add `inline` to trivial cross-crate accessors by traviscross · Pull Request #156343 · rust-lang/rust

traviscross · 2026-05-08T20:21:14Z

Note

This is a draft for running perf.

Small accessor functions aren't inlined across crate boundaries in all build configurations. Even with LTO, PGO, etc., we may be limited in what gets inlined without these annotations.

In detailed profiling, the inline attributes being added in this PR seemed to make a difference. Let's add them.

Notably, some of these fall within the expansion of the newtype_index! macro and will apply to the items it defines.

r? @traviscross

traviscross · 2026-05-08T20:21:39Z

@bors try @rust-timer queue

…s, r=<try> [PERF CHECK ONLY] Add `inline` to trivial cross-crate accessors

rust-bors · 2026-05-08T22:30:34Z

☀️ Try build successful (CI)
Build commit: 6000502 (6000502f00011b1e462abca902ad51df79f2d675, parent: 8068e2fc9afa8c888336b12db01987be768785f9)

rust-timer · 2026-05-08T23:12:03Z

Finished benchmarking commit (6000502): comparison URL.

Overall result: ❌✅ regressions and improvements - please read:

Benchmarking means the PR may be perf-sensitive. It's automatically marked not fit for rolling up. Overriding is possible but disadvised: it risks changing compiler perf.

Next, please: If you can, justify the regressions found in this try perf run in writing along with @rustbot label: +perf-regression-triaged. If not, fix the regressions and do another perf run. Neutral or positive results will clear the label automatically.

@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)	3.4%	[3.4%, 3.4%]	1
Regressions ❌ (secondary)	1.2%	[0.2%, 2.3%]	2
Improvements ✅ (primary)	-0.4%	[-0.6%, -0.1%]	11
Improvements ✅ (secondary)	-0.9%	[-1.0%, -0.8%]	6
All ❌✅ (primary)	-0.1%	[-0.6%, 3.4%]	12

Max RSS (memory usage)

Results (primary 1.4%, secondary 0.5%)

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

	mean	range	count
Regressions ❌ (primary)	1.4%	[1.4%, 1.4%]	1
Regressions ❌ (secondary)	3.2%	[3.2%, 3.2%]	1
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-2.2%	[-2.2%, -2.2%]	1
All ❌✅ (primary)	1.4%	[1.4%, 1.4%]	1

Cycles

Results (secondary 2.8%)

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

	mean	range	count
Regressions ❌ (primary)	-	-	0
Regressions ❌ (secondary)	2.8%	[2.8%, 2.8%]	1
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	-	-	0

Binary size

This perf run didn't have relevant results for this metric.

Bootstrap: 498.048s -> 501.772s (0.75%)
Artifact size: 397.10 MiB -> 397.12 MiB (0.00%)

traviscross · 2026-05-08T23:17:27Z

@bors try @rust-timer queue

traviscross · 2026-05-08T23:20:48Z

@bors try @rust-timer queue

…s, r=<try> [PERF CHECK ONLY] Add `inline` to trivial cross-crate accessors

traviscross · 2026-05-09T02:21:15Z

@bors try @rust-timer queue

…s, r=<try> [PERF CHECK ONLY] Add `inline` to trivial cross-crate accessors

rust-bors · 2026-05-09T04:30:24Z

☀️ Try build successful (CI)
Build commit: c51601b (c51601be0e9654351a230f76a0910211ce8897a9, parent: fb0a5a5a9c892b351f34263d6d84da9dde72871a)

rust-timer · 2026-05-09T05:47:31Z

Finished benchmarking commit (c51601b): comparison URL.

Overall result: ❌✅ regressions and improvements - please read:

Benchmarking means the PR may be perf-sensitive. It's automatically marked not fit for rolling up. Overriding is possible but disadvised: it risks changing compiler perf.

Next, please: If you can, justify the regressions found in this try perf run in writing along with @rustbot label: +perf-regression-triaged. If not, fix the regressions and do another perf run. Neutral or positive results will clear the label automatically.

@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)	3.3%	[3.3%, 3.3%]	1
Regressions ❌ (secondary)	0.8%	[0.2%, 2.4%]	4
Improvements ✅ (primary)	-0.4%	[-0.6%, -0.2%]	14
Improvements ✅ (secondary)	-0.4%	[-1.1%, -0.1%]	20
All ❌✅ (primary)	-0.1%	[-0.6%, 3.3%]	15

Max RSS (memory usage)

Results (secondary 1.1%)

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

	mean	range	count
Regressions ❌ (primary)	-	-	0
Regressions ❌ (secondary)	2.6%	[2.3%, 3.0%]	3
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-3.2%	[-3.2%, -3.2%]	1
All ❌✅ (primary)	-	-	0

Cycles

Results (primary -2.2%)

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

	mean	range	count
Regressions ❌ (primary)	-	-	0
Regressions ❌ (secondary)	-	-	0
Improvements ✅ (primary)	-2.2%	[-2.2%, -2.2%]	1
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	-2.2%	[-2.2%, -2.2%]	1

Binary size

Results (secondary -0.1%)

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

	mean	range	count
Regressions ❌ (primary)	-	-	0
Regressions ❌ (secondary)	-	-	0
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-0.1%	[-0.1%, -0.1%]	1
All ❌✅ (primary)	-	-	0

Bootstrap: 497.93s -> 502.373s (0.89%)
Artifact size: 397.14 MiB -> 396.95 MiB (-0.05%)

rust-bors · 2026-05-10T13:48:02Z

☀️ Try build successful (CI)
Build commit: 4a10250 (4a10250184a5c9aee22a012d54bce26ace0b5f08, parent: fb0a5a5a9c892b351f34263d6d84da9dde72871a)

rust-timer · 2026-05-10T15:43:00Z

Finished benchmarking commit (4a10250): comparison URL.

Overall result: ❌ regressions - please read:

Benchmarking means the PR may be perf-sensitive. It's automatically marked not fit for rolling up. Overriding is possible but disadvised: it risks changing compiler perf.

Next, please: If you can, justify the regressions found in this try perf run in writing along with @rustbot label: +perf-regression-triaged. If not, fix the regressions and do another perf run. Neutral or positive results will clear the label automatically.

@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)	22.9%	[5.3%, 36.7%]	269
Regressions ❌ (secondary)	22.7%	[4.9%, 60.5%]	327
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	22.9%	[5.3%, 36.7%]	269

Max RSS (memory usage)

Results (primary 19.9%, secondary 31.6%)

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

	mean	range	count
Regressions ❌ (primary)	19.9%	[2.6%, 70.5%]	262
Regressions ❌ (secondary)	31.6%	[1.3%, 76.2%]	327
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	19.9%	[2.6%, 70.5%]	262

Cycles

Results (primary 22.5%, secondary 24.0%)

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

	mean	range	count
Regressions ❌ (primary)	22.5%	[7.0%, 42.6%]	269
Regressions ❌ (secondary)	24.0%	[6.7%, 76.0%]	326
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	22.5%	[7.0%, 42.6%]	269

Binary size

This perf run didn't have relevant results for this metric.

Bootstrap: 497.93s -> 666.116s (33.78%)
Artifact size: 397.14 MiB -> 313.43 MiB (-21.08%)

traviscross · 2026-05-10T21:10:23Z

@bors try parent=fdd8554059ec6dbba1d2c7aafb4d6c730d52cb90 @rust-timer queue

…s, r=<try> [PERF CHECK ONLY] Add `inline` to trivial cross-crate accessors

rust-bors · 2026-05-10T21:55:43Z

☀️ Try build successful (CI)
Build commit: 98af79b (98af79b3d0f1181bf0cc36509f4c42c4d7c564ce, parent: fdd8554059ec6dbba1d2c7aafb4d6c730d52cb90)

traviscross · 2026-05-10T22:05:08Z

@bors try parent=fdd8554059ec6dbba1d2c7aafb4d6c730d52cb90 @rust-timer queue

…s, r=<try> [PERF CHECK ONLY] Add `inline` to trivial cross-crate accessors

rust-bors · 2026-05-10T22:48:35Z

☀️ Try build successful (CI)
Build commit: 084fe78 (084fe7801fee2c726dca8f7f3ec985bf3980f4b7, parent: fdd8554059ec6dbba1d2c7aafb4d6c730d52cb90)

traviscross · 2026-05-10T23:21:49Z

@rust-timer build 084fe78

traviscross · 2026-05-10T23:26:17Z

@bors try parent=4a10250184a5c9aee22a012d54bce26ace0b5f08

…s, r=<try> [PERF CHECK ONLY] Add `inline` to trivial cross-crate accessors

rust-bors · 2026-05-11T00:11:12Z

☀️ Try build successful (CI)
Build commit: ce5a3fd (ce5a3fd1bce34bc1261c3cf08db86754046e51be, parent: 4a10250184a5c9aee22a012d54bce26ace0b5f08)

traviscross · 2026-05-11T03:11:43Z

@rust-timer build ce5a3fd

rust-timer · 2026-05-11T03:55:59Z

Finished benchmarking commit (ce5a3fd): comparison URL.

Overall result: ❌✅ regressions and improvements - please read:

Benchmarking means the PR may be perf-sensitive. It's automatically marked not fit for rolling up. Overriding is possible but disadvised: it risks changing compiler perf.

Next, please: If you can, justify the regressions found in this try perf run in writing along with @rustbot label: +perf-regression-triaged. If not, fix the regressions and do another perf run. Neutral or positive results will clear the label automatically.

@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
Regressions ❌ (secondary)	0.4%	[0.4%, 0.4%]	6
Improvements ✅ (primary)	-0.4%	[-0.5%, -0.3%]	9
Improvements ✅ (secondary)	-0.6%	[-0.7%, -0.3%]	13
All ❌✅ (primary)	-0.4%	[-0.5%, -0.3%]	9

Max RSS (memory usage)

Results (primary 0.4%, secondary 0.4%)

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

	mean	range	count
Regressions ❌ (primary)	0.7%	[0.4%, 3.1%]	51
Regressions ❌ (secondary)	0.6%	[0.4%, 1.4%]	70
Improvements ✅ (primary)	-0.8%	[-2.3%, -0.4%]	11
Improvements ✅ (secondary)	-1.2%	[-3.2%, -0.4%]	11
All ❌✅ (primary)	0.4%	[-2.3%, 3.1%]	62

Cycles

Results (primary -0.3%, secondary -0.3%)

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

	mean	range	count
Regressions ❌ (primary)	0.8%	[0.4%, 2.6%]	49
Regressions ❌ (secondary)	1.0%	[0.4%, 5.5%]	59
Improvements ✅ (primary)	-0.8%	[-2.8%, -0.4%]	88
Improvements ✅ (secondary)	-1.0%	[-2.6%, -0.4%]	112
All ❌✅ (primary)	-0.3%	[-2.8%, 2.6%]	137

Binary size

This perf run didn't have relevant results for this metric.

Bootstrap: 666.116s -> 680.55s (2.17%)
Artifact size: 313.43 MiB -> 313.38 MiB (-0.02%)

rustbot assigned traviscross May 8, 2026

rustbot added S-waiting-on-author Status: This is awaiting some action (such as code changes or more information) from the author. T-compiler Relevant to the compiler team, which will review and decide on the PR/issue. labels May 8, 2026