Start using pattern types in libcore

[oli-obk]

cc #135996

blocked on rust-analyzer getting support for computing the right layout for pattern types

cc @Veykril no rush here, as long as we can't replace NonNull, there's no point in doing this change just yet

[compiler-errors]

Well r=me when/if it does get unblocked.

[scottmcm]

Unsure: at least for the NonZeroBlahInner ones, it'd be nicer if these could just be type $name = pattern_type!($int is $low..=$high);, without the extra wrapper. Is that feasible, or are the trait implementations too far off?

(Relatedly, I'd love to be able to just derive traits on these again, particularly to not have to manually StructuralPartialEq.)

[oli-obk]

Yea... I wanna get there, but directly using pattern types is not a great experience at present

[rustbot]

Some changes occurred to MIR optimizations

cc @rust-lang/wg-mir-opt

[Veykril]

Re rust-analyzer blocker, as it turns out to implement pattern types (to a degree that would unblock this) it comes down to the same architecture changes required as for rust-lang/rust-analyzer#7434 (which I am currently looking into), so that will take a bit.

[rustbot]

Some changes occurred to the CTFE machinery

cc @rust-lang/wg-const-eval

Some changes occurred to the CTFE / Miri interpreter

cc @rust-lang/miri

[tmiasko]

Pattern types temporarily reusing tuple encoding risk breakage due to symbol conflicts. For example, the following fails to compile with -Csymbol-mangling-version=v0:

#![feature(pattern_types)]
#![feature(pattern_type_macro)]
use std::hint::black_box;
use std::mem::size_of;
use std::pat::pattern_type;

fn main() {
    black_box(size_of::<pattern_type!(usize is 0..=1)> as fn() -> usize);
    black_box(size_of::<(usize, [(); 0], [(); 1])> as fn() -> usize);
}

[oli-obk]

Ah yea, I guess I need to change rustc-demangle first, then update our internal dependency on it, then update what we emit

[bors]

☔ The latest upstream changes (presumably #142556) made this pull request unmergeable. Please resolve the merge conflicts.

[bors]

☔ The latest upstream changes (presumably #143582) made this pull request unmergeable. Please resolve the merge conflicts.

[rustbot]

This PR changes rustc_public

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

[bors]

☔ The latest upstream changes (presumably #144249) made this pull request unmergeable. Please resolve the merge conflicts.

[bors]

☔ The latest upstream changes (presumably #143897) made this pull request unmergeable. Please resolve the merge conflicts.

[bors]

☔ The latest upstream changes (presumably #144814) made this pull request unmergeable. Please resolve the merge conflicts.

[rustbot]

This PR was rebased onto a different master 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.

[rust-log-analyzer]

The job pr-check-2 failed! Check out the build log: (web) (plain enhanced) (plain)

Click to see the possible cause of the failure (guessed by this bot)

    |
793 |         match self.inner() {
    |               ^^^^^^^^^^^^ pattern `&rustc_type_ir::PatternKind::NotNull` not covered
    |
note: `rustc_type_ir::PatternKind<next_solver::interner::DbInterner<'_>>` defined here
   --> /checkout/compiler/rustc_type_ir/src/pattern.rs:14:1
    |
 14 | pub enum PatternKind<I: Interner> {
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
...
 17 |     NotNull,
    |     ------- not covered
    = note: the matched value is of type `&rustc_type_ir::PatternKind<next_solver::interner::DbInterner<'_>>`
help: ensure that all possible cases are being handled by adding a match arm with a wildcard pattern or an explicit pattern as shown
    |
804 ~             },
805 +             &rustc_type_ir::PatternKind::NotNull => todo!()
    |

error[E0004]: non-exhaustive patterns: `&rustc_type_ir::PatternKind::NotNull` not covered
   --> src/tools/rust-analyzer/crates/hir-ty/src/next_solver/interner.rs:809:15
    |
809 |         match self.inner() {
    |               ^^^^^^^^^^^^ pattern `&rustc_type_ir::PatternKind::NotNull` not covered
    |
note: `rustc_type_ir::PatternKind<next_solver::interner::DbInterner<'_>>` defined here
   --> /checkout/compiler/rustc_type_ir/src/pattern.rs:14:1
    |
 14 | pub enum PatternKind<I: Interner> {
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
...
 17 |     NotNull,
    |     ------- not covered
    = note: the matched value is of type `&rustc_type_ir::PatternKind<next_solver::interner::DbInterner<'_>>`
help: ensure that all possible cases are being handled by adding a match arm with a wildcard pattern or an explicit pattern as shown
    |
819 ~             },
820 +             &rustc_type_ir::PatternKind::NotNull => todo!()
    |

error[E0004]: non-exhaustive patterns: `(rustc_type_ir::PatternKind::NotNull, _)` not covered
   --> src/tools/rust-analyzer/crates/hir-ty/src/next_solver/interner.rs:838:15
    |
838 |         match (a.kind(), b.kind()) {
    |               ^^^^^^^^^^^^^^^^^^^^ pattern `(rustc_type_ir::PatternKind::NotNull, _)` not covered
    |
    = note: the matched value is of type `(rustc_type_ir::PatternKind<next_solver::interner::DbInterner<'_>>, rustc_type_ir::PatternKind<next_solver::interner::DbInterner<'_>>)`
help: ensure that all possible cases are being handled by adding a match arm with a wildcard pattern or an explicit pattern as shown
    |
857 ~             (PatternKind::Range { .. } | PatternKind::Or(_), _) => Err(TypeError::Mismatch),
858 ~             (rustc_type_ir::PatternKind::NotNull, _) => todo!(),
    |

[RUSTC-TIMING] serde_value test:false 0.301
    Checking protobuf-support v3.7.1
[RUSTC-TIMING] toml test:false 0.593