Fix missing impl trait display as ret type
I need to convert a `TraitPredicate` into a `TraitBound` to get the returned impl trait. So far, didn't find how or even if it was the good way to do it.
cc @eddyb @oli-obk (since you're the one behind the change apparently 😉)
Set applicability for more suggestions.
Converts a couple more calls to `span_suggestion_with_applicability` (#50723). To be on the safe side, I marked suggestions that depend on the intent of the user or that are potentially lossy conversions as MaybeIncorrect.
r? @estebank
fix array drop glue: properly turn raw ptr into reference
Discovered while working on https://github.com/rust-lang/rust/pull/53424: The generated drop glue uses an assignment `ptr = cur` where `ptr` is a reference and `cur` a raw pointer. This is not well-formed MIR.
Do we have MIR sanity checks that run on the drop glue and should have caught this?
r? @eddyb
Buffer LLVM's object output stream
In some profiling on OSX I saw the `write` syscall as quite high up on
the profiling graph, which is definitely not good! It looks like we're
setting the output stream of an object file as directly to a file
descriptor which means that we run the risk of doing lots of little
writes rather than a few large writes.
This commit fixes this issue by adding a buffered stream on the output,
causing the `write` syscall to disappear from the profiles on OSX.
CTFE engine refactor
* Value gets renamed to `Operand`, so that now `interpret::{Place, Operand}` are the "dynamic" versions of `mir::{Place, Operand}`.
* `Operand` and `Place` share the data for their "stuff is in memory"-base in a new type, `MemPlace`. This also makes it possible to give some more precise types in other areas. Both `Operand` and `MemPlace` have methods available to project into fields (and other kinds of projections) without causing further allocations.
* The type for "a `Scalar` or a `ScalarPair`" is called `Value`, and again used to give some more precise types.
* All of these have versions with an attached layout, so that we can more often drag the layout along instead of recomputing it. This lets us get rid of `PlaceExtra::Downcast`. `MPlaceTy` and `PlaceTy` can only be constructed in place.rs, making sure the layout is handled properly. (The same should eventually be done for `ValTy` and `OpTy`.)
This is used to check, when copying an operand to a place, that the sizes match (which caught a bunch of bugs).
* All the high-level functions to write typed memory take a `Place`, and live in `place.rs`. All the high-level typed functions to read typed memory take an `Operand`, and live in `operands.rs`.
* Remove `cur_frame` and handling of signedess from memory (catching a bug in the float casting code).
* [Only functional change] Enable sanity check to recurse below dyn traits and slices.
r? @oli-obk
Cc @eddyb
During the sanity check, we keep track of the path we are below in a `Vec`. We
avoid cloning that `Vec` unless we hit a pointer indirection. The `String`
representation is only computed when validation actually fails.
This is still roughly 45ns slower than the old state, because it now works with
an MPlaceTy and uses the appropriate abstractions, instead of working with a
ptr-align pair directly.
