Store chunk_domain_size explicitly in Chunk.

[nnethercote]

Currently we compute it on demand, but it's a little simpler and slightly faster to store it.

r? @ghost

[nnethercote]

@bors try @rust-timer queue

[rust-bors]

☀️ Try build successful (CI)
Build commit: f2dee36 (f2dee36bae6b48e996359e187e06284c26c6d3fb, parent: 28c4c7d7abced7b35c49f38149b9cb6ea27dd2a6)

[rust-timer]

Finished benchmarking commit (f2dee36): comparison URL.

Overall result: ✅ improvements - no action needed

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.

@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
Improvements ✅ (primary)	-0.9%	[-1.3%, -0.5%]	4
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	-0.9%	[-1.3%, -0.5%]	4

Max RSS (memory usage)

Results (secondary 3.9%)

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)	3.9%	[3.9%, 3.9%]	1
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	-	-	0

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 benchmark run did not return any relevant results for this metric.

Bootstrap: 474.3s -> 474.199s (-0.02%)
Artifact size: 390.30 MiB -> 390.38 MiB (0.02%)

[cjgillot]

Haha I removed it 2 months ago... #145480

[nnethercote]

@bors try @rust-timer queue

[rust-bors]

☀️ Try build successful (CI)
Build commit: 3292998 (3292998ac4db5a85e367e401dd12f438b3ce18c3, parent: b41f22de2a13a0babd28771e96feef4c309f54aa)

[rust-timer]

Finished benchmarking commit (3292998): comparison URL.

Overall result: ✅ improvements - no action needed

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.

@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
Improvements ✅ (primary)	-0.7%	[-1.2%, -0.1%]	4
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	-0.7%	[-1.2%, -0.1%]	4

Max RSS (memory usage)

Results (primary 1.3%)

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

	mean	range	count
Regressions ❌ (primary)	1.3%	[1.3%, 1.3%]	1
Regressions ❌ (secondary)	-	-	0
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	1.3%	[1.3%, 1.3%]	1

Cycles

Results (primary 3.1%, secondary 2.4%)

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

	mean	range	count
Regressions ❌ (primary)	3.1%	[3.1%, 3.1%]	1
Regressions ❌ (secondary)	2.4%	[2.4%, 2.4%]	1
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	3.1%	[3.1%, 3.1%]	1

Binary size

This benchmark run did not return any relevant results for this metric.

Bootstrap: 478.517s -> 480.21s (0.35%)
Artifact size: 395.02 MiB -> 396.97 MiB (0.49%)

[nnethercote]

@cjgillot: going back is a small perf win on cranelift, and the code is bit more concise too. What do you think?

[rust-bors]

☔ The latest upstream changes (presumably #153865) made this pull request unmergeable. Please resolve the merge conflicts.

[wesleywiser]

r? rust-lang/compiler

[Mark-Simulacrum]

Since I reviewed #145480, probably might as well look at this. r? Mark-Simulacrum

[nnethercote]

FWIW, the context here is that I wrote the original code, and then it was modified (without my knowledge), and then I was looking at it much later and thought "hmm, it seems like it would be better like this" and I managed to perfectly undo the modification and revert it to the original form without realizing. So, points for consistency if nothing else?

[Mark-Simulacrum]

r=me with a rebase (and optionally a clean perf run), since perf is slightly positive. But I don't have a strong opinion over whether to store this or not from a code quality perspective.

Maybe worth adding a comment to the field noting that we've chosen to keep it for now, linking the ~3 involved PRs?