Don't `alloca` just to look at a discriminant
Today we're making LLVM do a bunch of extra work when you match on trivial stuff like `Option<bool>` or `ControlFlow<u8>`.
This PR changes that so that simple types like `Option<u32>` or `Result<(), Box<Error>>` can stay as `OperandValue::ScalarPair` and we can still read the discriminant from them, rather than needing to write them into memory to have a `PlaceValue` just to get the discriminant out.
Fixes#137503
Currently (PatKind::Wild` (i.e. `_`) gets turned by
`lower_fn_params_to_names` into an empty identifier, which means it is
printed incorrectly by HIR pretty printing.
And likewise for `lower_fn_params_to_names`, which affects some error
messages.
This commit fixes them. This requires a slight tweak in a couple of
places to continue using parameter numbers in some error messages. And
it improves the output of `tests/ui/typeck/cyclic_type_ice.rs`:
`/* _ */` is a better suggestion than `/* */`.
The original reason to exclude it was so it could run before submodules
were initialized. However, those have all been converted to subtrees
now, so the entire workspace is always ready to go.
They *used* to not work, however this was fixed in the PR that added the
test. I forgot to remove this line or possibly lost its removal while
rebasing.
Fix RISC-V VxWorks LLVM target triples
The targets `riscv32-wrs-vxworks` and `riscv64-wrs-vxworks` uses the plain `$ARCH` LLVM triple, which LLVM normalizes to `$ARCH-unknown-unknown`, we should use `$ARCH-unknown-linux-gnu$ABI` which is consistent with the the other VxWorks targets.
Motivation: To make it easier to verify that [`cc-rs`' conversion from `rustc` to Clang/LLVM triples](https://github.com/rust-lang/cc-rs/issues/1431) is correct.
Alternative: Pass `$ARCH-unknown-none` in the other VxWorks LLVM triples, I don't know anything about VxWorks, so am unsure which is the most correct option.
CC target maintainer `@biabbas.`
r? jieyouxu
minor interpreter cleanups
- remove the `eval_inline_asm` hook that `@saethlin` added; the usage never materialized and he agreed with removing it
- I tried merging `init_alloc_extra` and `adjust_global_allocation` and it didn't work; leave a comment as to why. Also, make the allocation code path a bit more clear by renaming `init_alloc_extra` to `init_local_allocation`.
r? `@oli-obk`
Add an opt-out in pretty printing for RTN rendering
Today, we render RPITIT types like `impl Sized { T::method(..) }` when RTN is enabled. This is very useful for diagnostics, since it's often not clear what the `impl Sized` type means by itself, and it makes it clear that that's an RPITIT that can be bounded using RTN syntax. See #115624.
However, since we don't distinguish types that are rendered for the purposes of printing messages vs suggestions, this representation leaks into suggestions and turns into code that can't be parsed. This PR adds a new `with_types_for_suggestion! {}` and `with_types_for_signature! {}` options to the pretty printing architecture to make it clear that we're rendering a type for code suggestions.
This can be applied later as we find that we need it.
Add a .bss-like scheme for encoded const allocs
This check if all bytes are zero feel like it should be too slow, and instead we should have a flag that we track, but that seems hard. Let's see how this perfs first.
Also we can probably stash the "it's all zero actually" flag inside one of the other struct members that's already not using an entire byte. This optimization doesn't fire all that often, so it's possible that by sticking it in the varint length field, this PR actually makes rmeta size worse.
The name:/path path syntax is getting phased out in favor of
/scheme/name/path. Also using null: is no longer necessary as /dev/null
is available on Redox OS too.
