AliasTerm refactor

[WaffleLapkin]

follow up to #154758
tracking issue: #154941

[rustbot]

Some changes occurred in src/tools/clippy

cc @rust-lang/clippy

changes to the core type system

cc @lcnr

HIR ty lowering was modified

cc @fmease

Some changes occurred to the core trait solver

cc @rust-lang/initiative-trait-system-refactor

changes to the core type system

cc @lcnr

This PR changes rustc_public

cc @oli-obk, @celinval, @ouz-a, @makai410

Some changes occurred in compiler/rustc_sanitizers

cc @rcvalle

[BoxyUwU]

r? BoxyUwU

[Kivooeo]

a bit concerned about PredicateKind size increase, let's do a perf to make sure it's fine

@bors try @rust-timer queue

[rust-bors]

☀️ Try build successful (CI)
Build commit: 8206b39 (8206b39ff9d255d5785bd8d5ad84a4a3d9ef510c, parent: 2f201bccb3a7fb5a85b0fcfcc0a020a946d6d58a)

[rust-timer]

Finished benchmarking commit (8206b39): 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)	0.3%	[0.2%, 0.5%]	6
Regressions ❌ (secondary)	0.3%	[0.1%, 0.5%]	5
Improvements ✅ (primary)	-0.3%	[-0.5%, -0.2%]	22
Improvements ✅ (secondary)	-0.3%	[-0.5%, -0.2%]	10
All ❌✅ (primary)	-0.2%	[-0.5%, 0.5%]	28

Max RSS (memory usage)

Results (primary 0.5%, secondary 0.7%)

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

	mean	range	count
Regressions ❌ (primary)	0.8%	[0.6%, 1.2%]	5
Regressions ❌ (secondary)	0.7%	[0.4%, 0.9%]	3
Improvements ✅ (primary)	-0.8%	[-0.8%, -0.8%]	1
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	0.5%	[-0.8%, 1.2%]	6

Cycles

Results (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)	-	-	0
Regressions ❌ (secondary)	2.3%	[2.3%, 2.3%]	1
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-3.3%	[-3.3%, -3.3%]	1
All ❌✅ (primary)	-	-	0

Binary size

Results (secondary 0.0%)

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)	0.0%	[0.0%, 0.0%]	6
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	-	-	0

Bootstrap: 491.618s -> 491.67s (0.01%)
Artifact size: 394.25 MiB -> 394.33 MiB (0.02%)

[BoxyUwU]

I feel a bit unsure about the with_args method, i feel like it makes the callsites which are obligation.predicate.with_args much less clear what's going on. but I guess thats a more general issue that projection predicates have really confusingly fields.

this PR needs a rebase and can you link to the tracking issue in the description. thx

View changes since this review

[rustbot]

This PR was rebased onto a different main commit. Here's a range-diff highlighting what actually changed.

Rebasing is a normal part of keeping PRs up to date, so no action is needed—this note is just to help reviewers.

[WaffleLapkin]

Rebased & added the tracking issue to the PR description.