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.
Switching them to `Break(())` and `Continue(())` instead.
libs-api would like to remove these constants, so stop using them in compiler to make the removal PR later smaller.
This makes it possible to mutably borrow different fields of the MIR
body without resorting to methods like `basic_blocks_local_decls_mut_and_var_debug_info`.
To preserve validity of control flow graph caches in the presence of
modifications, a new struct `BasicBlocks` wraps together basic blocks
and control flow graph caches.
The `BasicBlocks` dereferences to `IndexVec<BasicBlock, BasicBlockData>`.
On the other hand a mutable access requires explicit `as_mut()` call.
The unconditional recursion lint determines if all execution paths
eventually lead to a self-recursive call.
The implementation always follows unwinding edges which limits its
practical utility. For example, it would not lint function `f` because a
call to `g` might unwind. It also wouldn't lint function `h` because an
overflow check preceding the self-recursive call might unwind:
```rust
pub fn f() {
g();
f();
}
pub fn g() { /* ... */ }
pub fn h(a: usize) {
h(a + 1);
}
```
To avoid the issue, assume that terminators that might continue
execution along non-unwinding edges do so.
Use ops::ControlFlow in rustc_data_structures::graph::iterate
Since I only know about this because you mentioned it,
r? @ecstatic-morse
If we're not supposed to use new `core` things in compiler for a while then feel free to close, but it felt reasonable to merge the two types since they're the same, and it might be convenient for people to use `?` in their traversal code.
(This doesn't do the type parameter swap; NoraCodes has signed up to do that one.)
