- moved work from `find_local` to `gather_statement`
- created custom iterator for `iter_projections`
- reverted change from `IndexVec` to `FxIndexMap`
Unify terminology used in unwind action and terminator, and reflect
the fact that a nounwind panic is triggered instead of an immediate
abort is triggered for this terminator.
(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
Treat Drop as a rmw operation
Previously, a Drop terminator was considered a move in MIR. This commit changes the behavior to only treat Drop as a mutable access to the dropped place.
In order for this change to be correct, we need to guarantee that
1. A dropped value won't be used again
2. Places that appear in a drop won't be used again before a
subsequent initialization.
We can ensure this to be correct at MIR construction because Drop will only be emitted when a variable goes out of scope, thus having:
* (1) as there is no way of reaching the old value. drop-elaboration
will also remove any uninitialized drop.
* (2) as the place can't be named following the end of the scope.
However, the initialization status, previously tracked by moves, should also be tied to the execution of a Drop, hence the additional logic in the dataflow analyses.
From discussion in [this thread](https://rust-lang.zulipchat.com/#narrow/stream/233931-t-compiler.2Fmajor-changes/topic/.60DROP.60.20to.20.60DROP_IF.60.20compiler-team.23558), originating from https://github.com/rust-lang/compiler-team/issues/558.
See also https://github.com/rust-lang/rust/pull/104488#discussion_r1085556010
Previously, a Drop terminator was considered a move in MIR.
This commit changes the behavior to only treat Drop as a mutable
access to the dropped place.
In order for this change to be correct, we need to guarantee that
a) A dropped value won't be used again
b) Places that appear in a drop won't be used again before a
subsequent initialization.
We can ensure this to be correct at MIR construction because Drop
will only be emitted when a variable goes out of scope,
thus having:
(a) as there is no way of reaching the old value. drop-elaboration
will also remove any uninitialized drop.
(b) as the place can't be named following the end of the scope.
However, the initialization status, previously tracked by moves,
should also be tied to the execution of a Drop, hence the
additional logic in the dataflow analyses.
This patch adds a `MirPass` that tracks the number of back-edges and
function calls in the CFG, adds a new MIR instruction to increment a
counter every time they are encountered during Const Eval, and emit a
warning if a configured limit is breached.
Convert all the crates that have had their diagnostic migration
completed (except save_analysis because that will be deleted soon and
apfloat because of the licensing problem).
Improve syntax of `newtype_index`
This makes it more like proper Rust and also makes the implementation a lot simpler.
Mostly just turns weird flags in the body into proper attributes.
It should probably also be converted to an attribute macro instead of function-like, but that can be done in a future PR.
Remove the `..` from the body, only a few invocations used it and it's
inconsistent with rust syntax.
Use `;` instead of `,` between consts. As the Rust syntax gods inteded.
This removes the `custom` format functionality as its only user was
trivially migrated to using a normal format.
If a new use case for a custom formatting impl pops up, you can add it
back.
