Print regions in type_name.

[nnethercote]

Currently they are skipped, which is a bit weird, and it sometimes causes malformed output like Foo<> and dyn Bar<, A = u32>.

Most regions are erased by the time type_name does its work. So all regions are now printed as '_ in non-optional places. Not perfect, but better than the status quo.

c_name is updated to trim lifetimes from MIR pass names, so that the PASS_NAMES sanity check still works. It is also renamed as simplify_pass_type_name and made non-const, because it doesn't need to be const and the non-const implementation is much shorter.

The commit also renames should_print_region as should_print_optional_region, which makes it clearer that it only applies to some regions.

Fixes #145168.

r? @lcnr

[rustbot]

Some changes occurred to the CTFE machinery

cc @RalfJung, @oli-obk, @lcnr

[rustbot]

Some changes occurred to MIR optimizations

cc @rust-lang/wg-mir-opt

[nnethercote]

@lcnr: new code is up. Quite a bit has changed.

@rustbot ready

[rustbot]

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  • 3720e1a

[nnethercote]

I updated again. c_name is now non-const, which is much nicer, and renamed as simplify_pass_type_name.

@rustbot ready

[lcnr]

I updated again. c_name is now non-const, which is much nicer, and renamed as simplify_pass_type_name.

@rustbot ready

i would expect that we've done it in a const block for 👻 perf 👻 reasons? 🤔

@bors2 try @rust-timer queue

[rust-bors]

☀️ Try build successful (CI)
Build commit: fc05a4f (fc05a4f44af11286e3ae4b0ab02b85685f709d2b, parent: 1553adfe6884a8f6c28f5a673d3e605535ee0113)

[rust-timer]

Finished benchmarking commit (fc05a4f): 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)	1.0%	[0.2%, 4.3%]	70
Regressions ❌ (secondary)	1.2%	[0.1%, 5.3%]	57
Improvements ✅ (primary)	-1.4%	[-1.4%, -1.4%]	1
Improvements ✅ (secondary)	-0.5%	[-1.4%, -0.0%]	3
All ❌✅ (primary)	0.9%	[-1.4%, 4.3%]	71

Max RSS (memory usage)

Results (secondary 4.2%)

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)	4.2%	[1.7%, 5.6%]	4
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	-	-	0

Cycles

Results (secondary 3.0%)

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)	4.0%	[3.0%, 6.0%]	9
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-5.8%	[-5.8%, -5.8%]	1
All ❌✅ (primary)	-	-	0

Binary size

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

Bootstrap: 464.093s -> 466.402s (0.50%)
Artifact size: 377.76 MiB -> 377.46 MiB (-0.08%)

[bors]

☔ The latest upstream changes (presumably #145366) made this pull request unmergeable. Please resolve the merge conflicts.