Validation introduced in #113124 allows UnwindAction::Continue and
TerminatorKind::Resume to occur only in functions with ABI that can
unwind. The function ABI depends on the panic strategy, which can vary
across crates.
Usually MIR is built and validated in the same crate. The coroutine drop
glue thus far was an exception. As a result validation could fail when
mixing different panic strategies.
Avoid the problem by executing AbortUnwindingCalls along with the
validation.
Don't do intra-pass validation on MIR shims
Fixes#114375
In the test that was committed, we end up generating the drop shim for `struct Foo` that looks like:
```
fn std::ptr::drop_in_place(_1: *mut Foo) -> () {
let mut _0: ();
bb0: {
goto -> bb5;
}
bb1: {
return;
}
bb2 (cleanup): {
resume;
}
bb3: {
goto -> bb1;
}
bb4 (cleanup): {
drop(((*_1).0: foo::WrapperWithDrop<()>)) -> [return: bb2, unwind terminate];
}
bb5: {
drop(((*_1).0: foo::WrapperWithDrop<()>)) -> [return: bb3, unwind: bb2];
}
}
```
In `bb4` and `bb5`, we assert that `(*_1).0` has type `WrapperWithDrop<()>`. However, In a user-facing param env, the type is actually `WrapperWithDrop<Tait>`. These types are not equal in a user-facing param-env (and can't be made equal even if we use `DefiningAnchor::Bubble`, since it's a non-local TAIT).
mir opt + codegen: handle subtyping
fixes#107205
the same issue was caused in multiple places:
- mir opts: both copy and destination propagation
- codegen: assigning operands to locals (which also propagates values)
I changed codegen to always update the type in the operands used for locals which should guard against any new occurrences of this bug going forward. I don't know how to make mir optimizations more resilient here. Hopefully the added tests will be enough to detect any trivially wrong optimizations going forward.
Move `mir::Field` → `abi::FieldIdx`
The first PR for https://github.com/rust-lang/compiler-team/issues/606
This is just the move-and-rename, because it's plenty big already. Future PRs will start using `FieldIdx` more broadly, and concomitantly removing `FieldIdx::new`s.
The first PR for https://github.com/rust-lang/compiler-team/issues/606
This is just the move-and-rename, because it's plenty big-and-bitrotty already. Future PRs will start using `FieldIdx` more broadly, and concomitantly removing `FieldIdx::new`s.
Since structs are always `VariantIdx(0)`, there's a bunch of files where the only reason they had `VariantIdx` or `vec::Idx` imported at all was to get the first variant.
So this uses a constant for that, and adds some doc-comments to `VariantIdx` while I'm there, since it doesn't have any today.
(This is a large commit. The changes to
`compiler/rustc_middle/src/ty/context.rs` are the most important ones.)
The current naming scheme is a mess, with a mix of `_intern_`, `intern_`
and `mk_` prefixes, with little consistency. In particular, in many
cases it's easy to use an iterator interner when a (preferable) slice
interner is available.
The guiding principles of the new naming system:
- No `_intern_` prefixes.
- The `intern_` prefix is for internal operations.
- The `mk_` prefix is for external operations.
- For cases where there is a slice interner and an iterator interner,
the former is `mk_foo` and the latter is `mk_foo_from_iter`.
Also, `slice_interners!` and `direct_interners!` can now be `pub` or
non-`pub`, which helps enforce the internal/external operations
division.
It's not perfect, but I think it's a clear improvement.
The following lists show everything that was renamed.
slice_interners
- const_list
- mk_const_list -> mk_const_list_from_iter
- intern_const_list -> mk_const_list
- substs
- mk_substs -> mk_substs_from_iter
- intern_substs -> mk_substs
- check_substs -> check_and_mk_substs (this is a weird one)
- canonical_var_infos
- intern_canonical_var_infos -> mk_canonical_var_infos
- poly_existential_predicates
- mk_poly_existential_predicates -> mk_poly_existential_predicates_from_iter
- intern_poly_existential_predicates -> mk_poly_existential_predicates
- _intern_poly_existential_predicates -> intern_poly_existential_predicates
- predicates
- mk_predicates -> mk_predicates_from_iter
- intern_predicates -> mk_predicates
- _intern_predicates -> intern_predicates
- projs
- intern_projs -> mk_projs
- place_elems
- mk_place_elems -> mk_place_elems_from_iter
- intern_place_elems -> mk_place_elems
- bound_variable_kinds
- mk_bound_variable_kinds -> mk_bound_variable_kinds_from_iter
- intern_bound_variable_kinds -> mk_bound_variable_kinds
direct_interners
- region
- intern_region (unchanged)
- const
- mk_const_internal -> intern_const
- const_allocation
- intern_const_alloc -> mk_const_alloc
- layout
- intern_layout -> mk_layout
- adt_def
- intern_adt_def -> mk_adt_def_from_data (unusual case, hard to avoid)
- alloc_adt_def(!) -> mk_adt_def
- external_constraints
- intern_external_constraints -> mk_external_constraints
Other
- type_list
- mk_type_list -> mk_type_list_from_iter
- intern_type_list -> mk_type_list
- tup
- mk_tup -> mk_tup_from_iter
- intern_tup -> mk_tup
There are several `mk_foo`/`intern_foo` pairs, where the former takes an
iterator and the latter takes a slice. (This naming convention is bad,
but that's a fix for another PR.)
This commit changes several `mk_foo` occurrences into `intern_foo`,
avoiding the need for some `.iter()`/`.into_iter()` calls. Affected
cases:
- mk_type_list
- mk_tup
- mk_substs
- mk_const_list