Remove InstanceKind::generates_cgu_internal_copy
This PR should not contain any behavior changes. Before this PR, the logic for selecting instantiation mode is spread across all of
* `instantiation_mode`
* `cross_crate_inlinable`
* `generates_cgu_internal_copy`
* `requires_inline`
The last two of those functions are not well-designed. The function that actually decides if we generate a CGU-internal copy is `instantiation_mode`, _not_ `generates_cgu_internal_copy`. The function `requires_inline` documents that it is about the LLVM `inline` attribute and that it is a hint. The LLVM attribute is called `inlinehint`, this function is also used by other codegen backends, and since it is part of instantiation mode selection it is *not* a hint.
The goal of this PR is to start cleaning up the logic into a sequence of checks that have a more logical flow and are easier to customize in the future (to do things like improve incrementality or improve optimizations without causing obscure linker errors because you forgot to update another part of the compiler).
Add a helper for building an owner id in ast lowering
Just some deduplication of owner-id creations. Will also help me later split up ast lowering into per-owner queries, as it won't be possible anymore to go from a NodeId to a DefId of an owner without doing extra work to check whether we have an owner id. So I'd just do that in the new `owner_id` function and keep the `local_def_id` function free of that logic
Fix/tweak some tests in new solver
Bunch of miscellaneous new solver tweaks that I found from the failing tests. Can split these out, but they all seemed small enough to not warrant separate PRs.
r? lcnr
Lower to a memset(undef) when Rvalue::Repeat repeats uninit
Fixes https://github.com/rust-lang/rust/issues/138625.
It is technically correct to just do nothing. But if we actually do nothing, we may miss that this is de-initializing something, so instead we just lower to a single memset that writes undef. This is still superior to the memcpy loop, in both quality of code we hand to the backend and LLVM's final output.
Lower BinOp::Cmp to llvm.{s,u}cmp.* intrinsics
Lowers `mir::BinOp::Cmp` (`three_way_compare` intrinsic) to the corresponding LLVM `llvm.{s,u}cmp.i8.*` intrinsics.
These are the intrinsics mentioned in https://github.com/rust-lang/rust/pull/118310, which are now available in LLVM 19.
I couldn't find any follow-up PRs/discussions about this, please let me know if I missed something.
r? `@scottmcm`
`with_scope` is only ever used for ast modules
Thus I renamed it to match other similar functions (`with_mod_rib`) and made it panic if used on non-modules
match lowering cleanup: remove unused unsizing logic from `non_scalar_compare`
Since array and slice constants are now translated to array and slice patterns, `non_scalar_compare` is only used for string comparisons. This specializes it to strings, renames it, and removes the unused array-unsizing logic.
This also updates the doc comments for `thir::PatKind::Constant` and `TestKind::Eq`, which referred to them being used for slice references.
r? ````@oli-obk````
Optimize hash map operations in the query system
This optimizes hash map operations in the query system by explicitly passing hashes and using more optimal operations. `find_or_find_insert_slot` in particular saves a hash table lookup over `entry`. It's not yet available in a safe API, but will be in https://github.com/rust-lang/hashbrown/pull/466.
<table><tr><td rowspan="2">Benchmark</td><td colspan="1"><b>Before</b></th><td colspan="2"><b>After</b></th></tr><tr><td align="right">Time</td><td align="right">Time</td><td align="right">%</th></tr><tr><td>🟣 <b>clap</b>:check</td><td align="right">1.6189s</td><td align="right">1.6129s</td><td align="right"> -0.37%</td></tr><tr><td>🟣 <b>hyper</b>:check</td><td align="right">0.2353s</td><td align="right">0.2337s</td><td align="right"> -0.67%</td></tr><tr><td>🟣 <b>regex</b>:check</td><td align="right">0.9344s</td><td align="right">0.9289s</td><td align="right"> -0.59%</td></tr><tr><td>🟣 <b>syn</b>:check</td><td align="right">1.4693s</td><td align="right">1.4652s</td><td align="right"> -0.28%</td></tr><tr><td>🟣 <b>syntex_syntax</b>:check</td><td align="right">5.6606s</td><td align="right">5.6439s</td><td align="right"> -0.30%</td></tr><tr><td>Total</td><td align="right">9.9185s</td><td align="right">9.8846s</td><td align="right"> -0.34%</td></tr><tr><td>Summary</td><td align="right">1.0000s</td><td align="right">0.9956s</td><td align="right"> -0.44%</td></tr></table>
r? `@cjgillot`
They're dodgy, covering all the keywords, including weak ones, and
edition-specific ones without considering the edition. They have a
single use in rustfmt. This commit changes that use to
`is_reserved_ident`, which is a much more widely used alternative and is
good enough, judging by the lack of effect on the test suite.
Tweaks to writeback and `Obligation -> Goal` conversion
Each of these commits are self-contained, but are prerequisites that I'd like to land before #138845, which still needs some cleaning.
The ""most controversial"" one is probably [Explicitly don't fold coroutine obligations in writeback](e7d27bae27), which I prefer because I think using `fold_predicate` to control against not normalizing predicates seems... easy to mess up 🤔, and we could have *other things* that we don't want to normalize.
Explicitly noting whether we want `resolve` to normalize is a lot clearer (and currently in writeback is limited to resolving stalled coroutine obligations), since we can attach it to a comment that explains *why*.
Cache current_dll_path output
Computing the current dll path is somewhat expensive relative to other work when compiling `fn main() {}` as `dladdr` needs to iterate over the symbol table of librustc_driver.so until it finds a match.
Don't attempt to export compiler-builtins symbols from rust dylibs
They are marked with hidden visibility to prevent them from getting exported, so we shouldn't ask the linker to export them anyway. The only thing that does it cause a warning on macOS.
Part of https://github.com/rust-lang/rust/issues/136096
cc `@jyn514`
Tweak type flags, fix missing flags from coroutine kind ty
Firstly, make sure we visit the coroutine kind ty. Since this kind ty is either infer (before upvar computation), or `()` or `i8`/`i16`/`i32`, this isn't really that big of a deal, since other types in the coroutine will also be infer, so we're not misreporting `ty.has_infer()` or anything, but it's still wrong not to do this.
Furthermore, remove `HAS_TY_COROUTINE`, since nobody used it, and also remove special casing for `STILL_FURTHER_SPECIALIZABLE` since it's likely not important anymore? I have a vague recollection that it was important for polymorphization(?), but no tests seem to rely on this behavior.
r? lcnr or reassign
Add unstable `--print=supported-crate-types` option
MCP: https://github.com/rust-lang/compiler-team/issues/836
Tracking issue: https://github.com/rust-lang/rust/issues/138640
### Test coverage
Two tests:
1. `tests/ui/print-request/stability.rs` to check that `--print=supported-crate-types` is `-Zunstable-options`-gated
2. `tests/ui/print-request/supported-crate-types.rs` is added as a basic smoke test. Observe that the compiler stdout corresponds to the below *Example output* section (e.g. `proc-macro` is unsupported on `wasm32-unknown-unknown` currently).
### Example output
<details>
<summary>For `x86_64-unknown-linux-gnu`</summary>
Notice the presence of `{c,}dylib` and `proc-macro`:
```
bin
cdylib
dylib
lib
proc-macro
rlib
staticlib
```
</details>
<details>
<summary>For `wasm32-unknown-unknown`</summary>
Notice the absence of `dylib` and `proc-macro`:
```
bin
cdylib
lib
rlib
staticlib
```
</details>
<details>
<summary>For `x86_64-unknown-linux-musl`</summary>
Notice the absence of `{c,}dylib` but presence of `proc-macro`:
```
bin
lib
proc-macro
rlib
staticlib
```
</details>
### Documentation
I added an entry in the unstable book's print request section to document this `supported-crate-types` print request.
### Unresolved questions
- [ ] (Name bikeshedding) is `supported-crate-types` a good name for the print request? I'm inclined to say it's good enough for an unstable print request, but may be worth revisiting at stabilization time.
### Stability
This print request being added is *unstable* in this PR. A separate stabilization PR following the usual compiler flag stabilization procedure should be filed for stabilization after some baking time.
### Review remarks
Best reviewed commit-by-commit.
r? compiler
Move some driver code around
`--emit mir`, `#[rustc_symbol_name]` and `#[rustc_def_path]` now run before codegen and thus work even if codegen fails. This can help with debugging.
