Add some extra information to opaque type cycle errors

[oli-obk]

Plus a bunch of cleanups.

This should help users debug query cycles due to auto trait checking. We'll probably want to fix cycle errors in most (or all?) cases by looking at the current item's hidden types (new solver does this), and by delaying the auto trait checks to after typeck.

[rustbot]

Thanks for the pull request, and welcome! The Rust team is excited to review your changes, and you should hear from @petrochenkov (or someone else) soon.

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[petrochenkov]

Everything looks reasonable (although I may be missing some context).
@bors r+

[bors]

📌 Commit 3278316ac08c310eee3f472dd0b524c48fbcbc66 has been approved by petrochenkov

It is now in the queue for this repository.

[bors]

☔ The latest upstream changes (presumably #113330) made this pull request unmergeable. Please resolve the merge conflicts.

[oli-obk]

cc @rust-lang/initiative-trait-system-refactor opinions on the last commit? 9e98feb It adds a new SelectionError variant

[BoxyUwU]

didn't look at actual diagnostic changes only the parts where the solver was changed. doesn't seem like it would have any bad interactions with new solver

[oli-obk]

@bors r=petrochenkov,BoxyUwU

[bors]

📌 Commit 9e98feb has been approved by petrochenkov,BoxyUwU

It is now in the queue for this repository.

[compiler-errors]

@rust-timer build a469b5fc80c0d4250147c756dc5c44516090467f

[rust-timer]

Finished benchmarking commit (a469b5fc80c0d4250147c756dc5c44516090467f): comparison URL.

Overall result: ❌ regressions - 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)	0.8%	[0.4%, 1.4%]	28
Regressions ❌ (secondary)	1.1%	[0.5%, 1.7%]	8
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	0.8%	[0.4%, 1.4%]	28

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)	5.1%	[5.1%, 5.1%]	1
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-2.6%	[-2.9%, -2.3%]	2
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)	3.1%	[1.2%, 5.0%]	11
Regressions ❌ (secondary)	-	-	0
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	3.1%	[1.2%, 5.0%]	11

Binary size

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

Bootstrap: 655.622s -> 654.779s (-0.13%)

[oli-obk]

The grammar regression looks like inliner noise I think?

105,507,958  ???:<rustc_infer::infer::resolve::OpportunisticVarResolver as rustc_type_ir::fold::FallibleTypeFolder<rustc_middle::ty::context::TyCtxt>>::try_fold_ty
-68,521,638  ???:<rustc_middle::ty::Ty as rustc_type_ir::fold::TypeSuperFoldable<rustc_middle::ty::context::TyCtxt>>::try_super_fold_with::<rustc_infer::infer::resolve::OpportunisticVarResolver>
 22,231,888  ???:<&rustc_middle::ty::list::List<rustc_middle::ty::subst::GenericArg> as rustc_type_ir::fold::TypeFoldable<rustc_middle::ty::context::TyCtxt>>::try_fold_with::<rustc_infer::infer::resolve::OpportunisticVarResolver>
 21,817,759  ???:<alloc::rc::Rc<rustc_middle::traits::ObligationCauseCode> as core::ops::drop::Drop>::drop
-15,533,809  ???:<rustc_trait_selection::traits::fulfill::FulfillmentContext as rustc_infer::traits::engine::TraitEngine>::register_predicate_obligation
 14,369,548  ???:<rustc_middle::ty::sty::Binder<rustc_middle::ty::sty::FnSig> as rustc_type_ir::fold::TypeSuperFoldable<rustc_middle::ty::context::TyCtxt>>::super_fold_with::<rustc_infer::infer::resolve::OpportunisticVarResolver>
-11,713,122  ???:<&rustc_middle::ty::list::List<rustc_middle::ty::Ty> as rustc_type_ir::fold::TypeFoldable<rustc_middle::ty::context::TyCtxt>>::try_fold_with::<rustc_infer::infer::resolve::OpportunisticVarResolver>
 11,314,135  ???:<rustc_infer::traits::Obligation<rustc_middle::ty::Predicate> as rustc_type_ir::fold::TypeFoldable<rustc_middle::ty::context::TyCtxt>>::fold_with::<rustc_infer::infer::resolve::OpportunisticVarResolver>
  9,825,260  ???:<rustc_trait_selection::traits::select::SelectionContext>::select
  9,052,738  ???:<alloc::vec::Vec<rustc_infer::traits::Obligation<rustc_middle::ty::Predicate>> as alloc::vec::spec_from_iter::SpecFromIter<rustc_infer::traits::Obligation<rustc_middle::ty::Predicate>, core::iter::adapters::filter::Filter<core::iter::adapters::map::Map<core::iter::adapters::zip::Zip<core::iter::adapters::zip::Zip<alloc::vec::into_iter::IntoIter<rustc_middle::ty::Clause>, alloc::vec::into_iter::IntoIter<rustc_span::span_encoding::Span>>, core::iter::adapters::rev::Rev<alloc::vec::into_iter::IntoIter<rustc_span::def_id::DefId>>>, <rustc_trait_selection::traits::wf::WfPredicates>::nominal_obligations_inner::{closure
 -8,275,607  ???:<rustc_infer::infer::InferCtxt>::commit_if_ok::<rustc_trait_selection::traits::project::ProjectAndUnifyResult, rustc_infer::traits::project::MismatchedProjectionTypes, rustc_trait_selection::traits::project::poly_project_and_unify_type::{closure
  8,070,019  ???:rustc_trait_selection::traits::project::poly_project_and_unify_type
 -7,213,695  ???:<rustc_trait_selection::traits::wf::WfPredicates>::compute

[oli-obk]

The regex regression has incr_comp_encode_dep_graph take more total time, even though there are fewer executions of it. I'm very confused 😆