Revert recent changes to dead code analysis
This is a revert to recent changes to dead code analysis, namely:
* efdf219 Rollup merge of #128104 - mu001999-contrib:fix/128053, r=petrochenkov
* a70dc297a8 Rollup merge of #127017 - mu001999-contrib:dead/enhance, r=pnkfelix
* 31fe9628cf Rollup merge of #127107 - mu001999-contrib:dead/enhance-2, r=pnkfelix
* 2724aeaaeb Rollup merge of #126618 - mu001999-contrib:dead/enhance, r=pnkfelix
* 977c5fd419 Rollup merge of #126315 - mu001999-contrib:fix/126289, r=petrochenkov
* 13314df21b Rollup merge of #125572 - mu001999-contrib:dead/enhance, r=pnkfelix
There is an additional change stacked on top, which suppresses false-negatives that were masked by this work. I believe the functions that are touched in that code are legitimately unused functions and the types are not reachable since this `AnonPipe` type is not publically reachable -- please correct me if I'm wrong cc `@NobodyXu` who added these in ##127153.
Some of these reverts (#126315 and #126618) are only included because it makes the revert apply cleanly, and I think these changes were only done to fix follow-ups from the other PRs?
I apologize for the size of the PR and the churn that it has on the codebase (and for reverting `@mu001999's` work here), but I'm putting this PR up because I am concerned that we're making ad-hoc changes to fix bugs that are fallout of these PRs, and I'd like to see these changes reimplemented in a way that's more separable from the existing dead code pass. I am happy to review any code to reapply these changes in a more separable way.
cc `@mu001999`
r? `@pnkfelix`
Fixes#128272Fixes#126169
nested aux-build in tests/rustdoc/ tests
* Fixes bug that prevented using nested aux-build in `tests/rustdoc/` tests. Before, `fn document` and the auxiliary builder disagreed about where to find the nested aux-build source file (`auxiliary/auxiliary/aux.rs` vs `auxiliary/aux.rs`), preventing them from building. Picked the latter in line with other builders in compiletest.
* Adds `//@ doc-flags` header, which forwards flags to rustdoc and not rustc.
* Adds `//@ unique-doc-out-dir` header, which sets the --out-dir for the rustdoc invocation to a unique directory: `<root out dir>/docs/<test name>/doc`
* Changes working directory of the rustdoc invocation to the root out directory (common among all aux-builds). Prior art: exec_compiled_test in runtest.rs
* Adds tests that use nested aux builds and new headers
These changes provide useful capabilities for writing rustdoc tests on their own. They are also needed to test the implementation for the [mergable-rustdoc-cross-crate-info](https://github.com/rust-lang/rfcs/pull/3662) RFC.
try-job: x86_64-msvc
Add `#[must_use]` to some `into_raw*` functions.
cc #121287
r? ``@cuviper``
Adds `#[must_use = "losing the pointer will leak memory"]`[^1] to `Box::into_raw(_with_allocator)`, `Vec::into_raw_parts(_with_alloc)`, `String::into_raw_parts`[^2], and `rc::{Rc, Weak}::into_raw_with_allocator` (Rc's normal `into_raw` and all of `Arc`'s `into_raw*`s are already `must_use`).
Adds `#[must_use = "losing the raw <resource name may leak resources"]` to `IntoRawFd::into_raw_fd`, `IntoRawSocket::into_raw_socket`, and `IntoRawHandle::into_raw_handle`.
[^1]: "*will* leak memory" may be too-strong wording (since `Box`/`Vec`/`String`/`rc::Weak` might not have a backing allocation), but I left it as-is for simplicity and consistency.
[^2]: `String::into_raw_parts`'s `must_use` message is changed from the previous (possibly misleading) "`self` will be dropped if the result is not used".
Added SHA512, SM3, SM4 target-features and `sha512_sm_x86` feature gate
This is an effort towards #126624. This adds support for these 3 target-features and introduces the feature flag `sha512_sm_x86`, which would gate these target-features and the yet-to-be-implemented detection and intrinsics in stdarch.
Migrate `cross-lang-lto-clang` and `cross-lang-lto-pgo-smoketest` `run-make` tests to rmake
Part of #121876 and the associated [Google Summer of Code project](https://blog.rust-lang.org/2024/05/01/gsoc-2024-selected-projects.html).
This has the same problem outlined by #126180, where the tests do not actually run as no test-running CI enviroment has `RUSTBUILD_FORCE_CLANG_BASED_TESTS` set.
However, I still find it interesting to turn the Makefiles into the rmake format until the Clang issue is fixed.
This should technically be tested on MSVC... if MSVC actually ran Clang tests.
try-job: x86_64-gnu-debug
Migrate `link-cfg` and `rustdoc-default-output` `run-make` tests to rmake
Part of #121876 and the associated [Google Summer of Code project](https://blog.rust-lang.org/2024/05/01/gsoc-2024-selected-projects.html).
try-job: aarch64-apple
try-job: x86_64-msvc
try-job: x86_64-mingw
try-job: x86_64-gnu-llvm-18
try-job: i686-msvc
Migrate `foreign-double-unwind`, `issue-36710` and `foreign-exceptions` `run-make` tests to rmake
Part of #121876 and the associated [Google Summer of Code project](https://blog.rust-lang.org/2024/05/01/gsoc-2024-selected-projects.html).
~~This is expected to fail CI, I am getting a weird `core dumped` error on `foreign-double-unwind` locally. Posting this to start a discussion.~~
EDIT: I got it, `foreign_double_unwind` is *supposed* to fail in the execution stage, but this wasn't obvious, because the original test was just piping the stdout to `CGREP` (which silently ignores errors).
try-job: aarch64-apple
try-job: armhf-gnu
try-job: test-various
try-job: x86_64-msvc
try-job: x86_64-gnu-llvm-18
try-job: i686-msvc
try-job: dist-i586-gnu-i586-i686-musl
Migrate `cross-lang-lto` `run-make` test to rmake
Part of #121876 and the associated [Google Summer of Code project](https://blog.rust-lang.org/2024/05/01/gsoc-2024-selected-projects.html).
Please try:
try-job: x86_64-msvc
try-job: i686-mingw
try-job: x86_64-mingw
try-job: armhf-gnu
try-job: test-various
try-job: aarch64-apple
try-job: x86_64-gnu-llvm-18
Rewrite binary search implementation
This PR builds on top of #128250, which should be merged first.
This restores the original binary search implementation from #45333 which has the nice property of having a loop count that only depends on the size of the slice. This, along with explicit conditional moves from #128250, means that the entire binary search loop can be perfectly predicted by the branch predictor.
Additionally, LLVM is able to unroll the loop when the slice length is known at compile-time. This results in a very compact code sequence of 3-4 instructions per binary search step and zero branches.
Fixes#53823Fixes#115271
Rollup of 6 pull requests
Successful merges:
- #126818 (Better handle suggestions for the already present code and fix some suggestions)
- #128436 (Update sysinfo version to 0.31.2)
- #128453 (raw_eq: using it on bytes with provenance is not UB (outside const-eval))
- #128491 ([`macro_metavar_expr_concat`] Dogfooding)
- #128494 (MIR required_consts, mentioned_items: ensure we do not forget to fill these lists)
- #128521 (rustdoc: Remove dead opaque_tys rendering logic)
r? `@ghost`
`@rustbot` modify labels: rollup
rustdoc: Remove dead opaque_tys rendering logic
#127276 removed OpaqueTy from clean, and the code populating AllTypes::opaque_tys, but not this field itself.
MIR required_consts, mentioned_items: ensure we do not forget to fill these lists
Bodies initially get created with empty required_consts and mentioned_items, but at some point those should be filled. Make sure we notice when that is forgotten.
raw_eq: using it on bytes with provenance is not UB (outside const-eval)
The current behavior of raw_eq violates provenance monotonicity. See https://github.com/rust-lang/rust/pull/124921 for an explanation of provenance monotonicity. It is violated in raw_eq because comparing bytes without provenance is well-defined, but adding provenance makes the operation UB.
So remove the no-provenance requirement from raw_eq. However, the requirement stays in-place for compile-time invocations of raw_eq, that indeed cannot deal with provenance.
Cc `@rust-lang/opsem`
Update sysinfo version to 0.31.2
I needed to update `memchr` version (which was pinned in 36a16798f7). So let's see if it triggers the linker issue.
try-job: x86_64-mingw
Better handle suggestions for the already present code and fix some suggestions
When a suggestion part is for code that is already present, skip it. If all the suggestion parts for a suggestion are for code that is already there, do not emit the suggestion.
Fix two suggestions that treat `span_suggestion` as if it were `span_help`.
