The current alignment check does not include checks for creating
misaligned references from raw pointers, which is now added in this
patch.
When inserting the check we need to be careful with references to
field projections (e.g. `&(*ptr).a`), in which case the resulting
reference must be aligned according to the field type and not the
type of the pointer.
Allow `IndexSlice` to be indexed by ranges.
This comes with some annoyances as the index type can no longer inferred from indexing expressions. The biggest offender for this is `IndexVec::from_fn_n(|idx| ..., n)` where the index type won't be inferred from the call site or any index expressions inside the closure.
My main use case for this is mapping a `Place` to `Range<Idx>` for value tracking where the range represents all the values the place contains.
The wording unsafe pointer is less common and not mentioned in a lot of
places, instead this is usually called a "raw pointer". For the sake of
uniformity, we rename this method.
This came up during the review of
https://github.com/rust-lang/rust/pull/134424.
Similar to how the alignment is already checked, this adds a check
for null pointer dereferences in debug mode. It is implemented similarly
to the alignment check as a MirPass.
This is related to a 2025H1 project goal for better UB checks in debug
mode: https://github.com/rust-lang/rust-project-goals/pull/177.
This also parameterize the "excluded pointee types" and exposes a
general method for inserting checks on pointers.
This is a preparation for adding a NullCheck that makes use of the same
code.