I'd prefer getting rid of it, but it's used in the impl search and not
super easy to replace there (I think ideally the impl search would do
proper unification, but that's a bit more complicated).
Almost all uses actually only care about ADT substs, so it's better to
be explicit. The methods were a bad abstraction anyway since they
already didn't include the inner types of e.g. `TyKind::Ref` anymore.
8364: Memory usage improvements r=jonas-schievink a=alexmaco
These are mostly focused on splitting up enum variants with large size differences between variants by `Box`-ing things up.
In my testing this reduces the memory usage somewhere in the low percentages, even though the measurements are quite noisy.
Co-authored-by: Alexandru Macovei <alexnmaco@gmail.com>
Rationale: only a minority of variants used almost half the size.
By keeping large members (especially in Option) behind a box
the memory cost is only payed when the large variants are needed.
This reduces the size Vec<Expr> needs to allocate.
- don't shift in/out for Chalk mapping (we want to have the same
binders now)
- do shift in when creating the signature for a closure (though it
shouldn't matter much)
- do shift in when lowering a `fn()` type
- correctly deal with the implied binder in TypeWalk
This is just the most trivial check: If no inference variables have been
updated, and there are no new obligations, we can just skip trying to
solve them again. We could be smarter about it, but this already helps
quite a bit, and I don't want to touch this too much before we replace
the inference table by Chalk's.
Fixes#8263 (well, improves it quite a bit).
We have a bug where type-checking `per_query_memory_usage` takes a
couple of seconds. It also reveals another bug: our type inference is
not cancellable.
8201: Fix recursive macro statements expansion r=edwin0cheng a=edwin0cheng
This PR attempts to properly handle macro statement expansion by implementing the following:
1. Merge macro expanded statements to parent scope statements.
2. Add a new hir `Expr::MacroStmts` for handle tail expression infer.
PS : The scope of macro expanded statements are so strange that it took more time than I thought to understand and implement it :(
Fixes #8171
Co-authored-by: Edwin Cheng <edwin0cheng@gmail.com>
