MIR: opt-in normalization of `BasicBlock` and `Local` numbering
This doesn't matter at all for actual codegen, but after spending some time reading pre-codegen MIR, I was wishing I didn't have to jump around so much in reading post-inlining code.
So this add two passes that are off by default for every mir level, but can be enabled (`-Zmir-enable-passes=+ReorderBasicBlocks,+ReorderLocals`) for humans.
Make `EarlyBinder`'s inner value private
Currently, `EarlyBinder(T)`'s inner value is public, which allows implicitly skipping the binder by indexing into the tuple struct (i.e., `x.0`). `@lcnr` suggested making `EarlyBinder`'s inner value private so users are required to explicitly call `skip_binder` (https://github.com/rust-lang/rust/issues/105779#issuecomment-1549933424) .
This PR makes the inner value private, adds `EarlyBinder::new` for constructing a new instance, and replaces uses of `x.0` with `x.skip_binder()` (or similar). It also adds some documentation to `EarlyBinder::skip_binder` explaining how to skip the binder of `&EarlyBinder<T>` to get `&T` now that the inner value is private (since previously we could just do `&x.0`).
r? `@lcnr`
Use only one shard with a single thread
This changes `Sharded` to only access a single shard using a mask set to `0` when a single thread is used, which leads to cache utilization improvements.
Performance improvement with 1 thread and `cfg(parallel_compiler)`:
<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">1.7402s</td><td align="right">1.7004s</td><td align="right">💚 -2.29%</td></tr><tr><td>🟣 <b>hyper</b>:check</td><td align="right">0.2633s</td><td align="right">0.2550s</td><td align="right">💚 -3.12%</td></tr><tr><td>🟣 <b>regex</b>:check</td><td align="right">0.9716s</td><td align="right">0.9482s</td><td align="right">💚 -2.41%</td></tr><tr><td>🟣 <b>syn</b>:check</td><td align="right">1.5679s</td><td align="right">1.5358s</td><td align="right">💚 -2.05%</td></tr><tr><td>🟣 <b>syntex_syntax</b>:check</td><td align="right">6.0569s</td><td align="right">5.9272s</td><td align="right">💚 -2.14%</td></tr><tr><td>Total</td><td align="right">10.5999s</td><td align="right">10.3666s</td><td align="right">💚 -2.20%</td></tr><tr><td>Summary</td><td align="right">1.0000s</td><td align="right">0.9760s</td><td align="right">💚 -2.40%</td></tr></table>
cc `@SparrowLii`
Don't check for misaligned raw pointer derefs inside Rvalue::AddressOf
From https://github.com/rust-lang/rust/pull/112026#issuecomment-1565686697:
rustc 1.70 (stable next week) added a Mir pass to add pointer alignment checks in debug mode. Adding these checks caused some crates to break, but that was expected, since they contain broken code (https://github.com/rust-lang/rust/issues/111487) for tracking that.
However, the checks added are slightly more aggressive than they should have been. Specifically, they also check the place in an `addr_of!` expression. Whether lack of alignment there is or isn't UB is unclear. This PR modifies the pass to not affect those cases.
I spot checked the crater regressions and the ones I saw were not the case that this PR is modifying. It still seems good to not land anything overaggressive though
Enable MatchBranchSimplification
This pass is one of the small number of benefits from `-Zmir-opt-level=3` that has motivated rustc_codegen_cranelift to use it:
19ed0aade6/compiler/rustc_codegen_cranelift/build_system/build_sysroot.rs (L244-L246)
Cranelift's motivation for this is _runtime_ performance improvements in debug builds. Lifting this pass all the way to `-Zmir-opt-level=1` seems to come without significant perf overhead, so that's what I'm suggesting here.
Migrate `item_foreign_type` to Askama
This PR continues the migration of `print_item.rs` functions to Askama. This piece of work migrates the function `item_foreign_type`
Refers https://github.com/rust-lang/rust/issues/108868
Add support for LLVM SafeStack
Adds support for LLVM [SafeStack] which provides backward edge control
flow protection by separating the stack into two parts: data which is
only accessed in provable safe ways is allocated on the normal stack
(the "safe stack") and all other data is placed in a separate allocation
(the "unsafe stack").
SafeStack support is enabled by passing `-Zsanitizer=safestack`.
[SafeStack]: https://clang.llvm.org/docs/SafeStack.html
cc `@rcvalle` #39699
Add warn-by-default lint when local binding shadows exported glob re-export item
This PR introduces a warn-by-default rustc lint for when a local binding (a use statement, or a type declaration) produces a name which shadows an exported glob re-export item, causing the name from the exported glob re-export to be hidden (see #111336).
### Unresolved Questions
- [x] ~~Is this approach correct? While it passes the UI tests, I'm not entirely convinced it is correct.~~ Seems to be ok now.
- [x] ~~What should the lint be called / how should it be worded? I don't like calling `use x::*;` or `struct Foo;` a "local binding" but they are `NameBinding`s internally if I'm not mistaken.~~ ~~The lint is called `local_binding_shadows_glob_reexport` for now, unless a better name is suggested.~~ `hidden_glob_reexports`.
Fixes#111336.
Rollup of 6 pull requests
Successful merges:
- #108630 (Fix docs for `alloc::realloc`)
- #109084 (rustc driver: Remove argument 0 before at-expansion to prevent ICE)
- #111181 (fix(parse): return unpected when current token is EOF)
- #111656 (Use an unbounded lifetime in `String::leak`.)
- #111946 (rustdoc: Add `ItemTemplate` trait and related functions to avoid repetitively wrapping existing functions)
- #112018 (Clean up usage of `cx.tcx` when `tcx` is already set into a variable)
r? `@ghost`
`@rustbot` modify labels: rollup
This reverts commit 9267843e72, reversing
changes made to e52fbff5e8.
This breaks our ability to bump the src/version where we're bootstrapping with an older compiler
than usual (according to version number). It's not clear whether the intended use case has a clean
solution given this constraint, so reverting for now - we can reland with a fix of some kind implemented.
Clean up usage of `cx.tcx` when `tcx` is already set into a variable
I discovered a few cases where `cx.tcx` (and equivalents) was used whereas `tcx` was already stored into a variable. In those cases, better to just use `tcx` directly.
r? `@notriddle`
rustc driver: Remove argument 0 before at-expansion to prevent ICE
Under Unix-based operating systems, when I execute rustc by setting argv0 to ``@/dev/null`,` it will expand command-line arguments from this file, leading to an empty arglist, which then triggers an ICE by trying to remove first argument.
The panic message is this:
```
thread 'main' panicked at 'range start index 1 out of range for slice of length 0', compiler/rustc_driver/src/lib.rs:972:17
```
My fix is to remove the first argument before expanding arguments.
<details>
<summary>Full backtrace</summary>
```sh
% (exec -a `@/dev/null` `rustup which rustc`)
thread 'main' panicked at 'range start index 1 out of range for slice of length 0', compiler/rustc_driver/src/lib.rs:972:17
stack backtrace:
0: 0x7fcec776659a - std::backtrace_rs::backtrace::libunwind::trace::h595f06c70adcc478
at /rustc/2c8cc343237b8f7d5a3c3703e3a87f2eb2c54a74/library/std/src/../../backtrace/src/backtrace/libunwind.rs:93:5
1: 0x7fcec776659a - std::backtrace_rs::backtrace::trace_unsynchronized::h177a0149c76cdde9
at /rustc/2c8cc343237b8f7d5a3c3703e3a87f2eb2c54a74/library/std/src/../../backtrace/src/backtrace/mod.rs:66:5
2: 0x7fcec776659a - std::sys_common::backtrace::_print_fmt::hc0701fd2c3530c58
at /rustc/2c8cc343237b8f7d5a3c3703e3a87f2eb2c54a74/library/std/src/sys_common/backtrace.rs:65:5
3: 0x7fcec776659a - <std::sys_common::backtrace::_print::DisplayBacktrace as core::fmt::Display>::fmt::hd4cd115d8750fd6c
at /rustc/2c8cc343237b8f7d5a3c3703e3a87f2eb2c54a74/library/std/src/sys_common/backtrace.rs:44:22
4: 0x7fcec77c839e - core::fmt::write::h93e2f5923c7eca08
at /rustc/2c8cc343237b8f7d5a3c3703e3a87f2eb2c54a74/library/core/src/fmt/mod.rs:1213:17
5: 0x7fcec7756be5 - std::io::Write::write_fmt::h8162dbb45f0b9e62
at /rustc/2c8cc343237b8f7d5a3c3703e3a87f2eb2c54a74/library/std/src/io/mod.rs:1682:15
6: 0x7fcec7766365 - std::sys_common::backtrace::_print::h1835ef8a8f9066da
at /rustc/2c8cc343237b8f7d5a3c3703e3a87f2eb2c54a74/library/std/src/sys_common/backtrace.rs:47:5
7: 0x7fcec7766365 - std::sys_common::backtrace::print::hcb5e6388b9235f41
at /rustc/2c8cc343237b8f7d5a3c3703e3a87f2eb2c54a74/library/std/src/sys_common/backtrace.rs:34:9
8: 0x7fcec776912f - std::panicking::default_hook::{{closure}}::h9c084969ccf9a722
at /rustc/2c8cc343237b8f7d5a3c3703e3a87f2eb2c54a74/library/std/src/panicking.rs:267:22
9: 0x7fcec7768e6b - std::panicking::default_hook::h68fa2ba3c3c6c12f
at /rustc/2c8cc343237b8f7d5a3c3703e3a87f2eb2c54a74/library/std/src/panicking.rs:286:9
10: 0x7fcecaab56e4 - <rustc_driver[f4ad927b3c57833d]::DEFAULT_HOOK::{closure#0}::{closure#0} as core[d16e85342ea223d9]::ops::function::FnOnce<(&core[d16e85342ea223d9]::panic::panic_info::PanicInfo,)>>::call_once::{shim:vtable#0}
11: 0x7fcec776996a - <alloc::boxed::Box<F,A> as core::ops::function::Fn<Args>>::call::h4e6ced11e07d8b24
at /rustc/2c8cc343237b8f7d5a3c3703e3a87f2eb2c54a74/library/alloc/src/boxed.rs:2002:9
12: 0x7fcec776996a - std::panicking::rust_panic_with_hook::h8d5c434518ef298c
at /rustc/2c8cc343237b8f7d5a3c3703e3a87f2eb2c54a74/library/std/src/panicking.rs:692:13
13: 0x7fcec77696e9 - std::panicking::begin_panic_handler::{{closure}}::hf33414f5dabf6faf
at /rustc/2c8cc343237b8f7d5a3c3703e3a87f2eb2c54a74/library/std/src/panicking.rs:579:13
14: 0x7fcec7766a4c - std::sys_common::backtrace::__rust_end_short_backtrace::hc50389427413bb75
at /rustc/2c8cc343237b8f7d5a3c3703e3a87f2eb2c54a74/library/std/src/sys_common/backtrace.rs:137:18
15: 0x7fcec77693f2 - rust_begin_unwind
at /rustc/2c8cc343237b8f7d5a3c3703e3a87f2eb2c54a74/library/std/src/panicking.rs:575:5
16: 0x7fcec77c4d43 - core::panicking::panic_fmt::h2de7a7938f816de8
at /rustc/2c8cc343237b8f7d5a3c3703e3a87f2eb2c54a74/library/core/src/panicking.rs:64:14
17: 0x7fcec77cb492 - core::slice::index::slice_start_index_len_fail_rt::h0c87d85ce11d10f6
at /rustc/2c8cc343237b8f7d5a3c3703e3a87f2eb2c54a74/library/core/src/slice/index.rs:53:5
18: 0x7fcec77cb416 - core::slice::index::slice_start_index_len_fail::h504609f2a6b168d1
at /rustc/2c8cc343237b8f7d5a3c3703e3a87f2eb2c54a74/library/core/src/slice/index.rs:41:9
19: 0x7fceca0eca1f - rustc_driver[f4ad927b3c57833d]::handle_options
20: 0x7fceca0e037f - <rustc_driver[f4ad927b3c57833d]::RunCompiler>::run
21: 0x7fceca0dfd0d - <core[d16e85342ea223d9]::panic::unwind_safe::AssertUnwindSafe<rustc_driver[f4ad927b3c57833d]::main::{closure#0}> as core[d16e85342ea223d9]::ops::function::FnOnce<()>>::call_once
22: 0x7fceca17ce89 - rustc_driver[f4ad927b3c57833d]::main
23: 0x564f5f008a87 - rustc_main[f164605d1302e295]::main
24: 0x564f5f008973 - std[3da461b304582a2c]::sys_common::backtrace::__rust_begin_short_backtrace::<fn(), ()>
25: 0x564f5f008969 - <std[3da461b304582a2c]::rt::lang_start<()>::{closure#0} as core[d16e85342ea223d9]::ops::function::FnOnce<()>>::call_once::{shim:vtable#0}
26: 0x7fcec774795c - core::ops::function::impls::<impl core::ops::function::FnOnce<A> for &F>::call_once::h699977d052768608
at /rustc/2c8cc343237b8f7d5a3c3703e3a87f2eb2c54a74/library/core/src/ops/function.rs:287:13
27: 0x7fcec774795c - std::panicking::try::do_call::h4e121e623c70f903
at /rustc/2c8cc343237b8f7d5a3c3703e3a87f2eb2c54a74/library/std/src/panicking.rs:483:40
28: 0x7fcec774795c - std::panicking::try::hf9d919e062bc178a
at /rustc/2c8cc343237b8f7d5a3c3703e3a87f2eb2c54a74/library/std/src/panicking.rs:447:19
29: 0x7fcec774795c - std::panic::catch_unwind::h7a7b12272684cb97
at /rustc/2c8cc343237b8f7d5a3c3703e3a87f2eb2c54a74/library/std/src/panic.rs:140:14
30: 0x7fcec774795c - std::rt::lang_start_internal::{{closure}}::hd96b0eb4844b8762
at /rustc/2c8cc343237b8f7d5a3c3703e3a87f2eb2c54a74/library/std/src/rt.rs:148:48
31: 0x7fcec774795c - std::panicking::try::do_call::h1af1f88f4f92a22c
at /rustc/2c8cc343237b8f7d5a3c3703e3a87f2eb2c54a74/library/std/src/panicking.rs:483:40
32: 0x7fcec774795c - std::panicking::try::hf20d7abea7f0f097
at /rustc/2c8cc343237b8f7d5a3c3703e3a87f2eb2c54a74/library/std/src/panicking.rs:447:19
33: 0x7fcec774795c - std::panic::catch_unwind::hb0e084c3a9c042e4
at /rustc/2c8cc343237b8f7d5a3c3703e3a87f2eb2c54a74/library/std/src/panic.rs:140:14
34: 0x7fcec774795c - std::rt::lang_start_internal::hca9d5c7277f5b67c
at /rustc/2c8cc343237b8f7d5a3c3703e3a87f2eb2c54a74/library/std/src/rt.rs:148:20
35: 0x564f5f008ab7 - main
36: 0x7fcec74a1790 - <unknown>
37: 0x7fcec74a184a - __libc_start_main
38: 0x564f5f00899e - <unknown>
39: 0x0 - <unknown>
error: internal compiler error: unexpected panic
note: the compiler unexpectedly panicked. this is a bug.
note: we would appreciate a bug report: https://github.com/rust-lang/rust/issues/new?labels=C-bug%2C+I-ICE%2C+T-compiler&template=ice.md
note: rustc 1.68.0 (2c8cc3432 2023-03-06) running on x86_64-unknown-linux-gnu
query stack during panic:
end of query stack
```
</details>
I also checked if I can trigger a similar problem by passing empty argument list to `execve`, but at least under Linux, it seems to always insert an empty first argument if there are none.
Fix docs for `alloc::realloc`
Fixes#108546.
Corrects the docs for `alloc::realloc` to bring the safety constraints into line with `Layout::from_size_align_unchecked`'s constraints.
Rework handling of recursive panics
This PR makes 2 changes to how recursive panics works (a panic while handling a panic).
1. The panic count is no longer used to determine whether to force an immediate abort. This allows code like the following to work without aborting the process immediately:
```rust
struct Double;
impl Drop for Double {
fn drop(&mut self) {
// 2 panics are active at once, but this is fine since it is caught.
std::panic::catch_unwind(|| panic!("twice"));
}
}
let _d = Double;
panic!("once");
```
Rustc already generates appropriate code so that any exceptions escaping out of a `Drop` called in the unwind path will immediately abort the process.
2. Any panics while the panic hook is executing will force an immediate abort. This is necessary to avoid potential deadlocks like #110771 where a panic happens while holding the backtrace lock. We don't even try to print the panic message in this case since the panic may have been caused by `Display` impls.
Fixes#110771
Rollup of 6 pull requests
Successful merges:
- #111936 (Include test suite metadata in the build metrics)
- #111952 (Remove DesugaringKind::Replace.)
- #111966 (Add #[inline] to array TryFrom impls)
- #111983 (Perform MIR type ops locally in new solver)
- #111997 (Fix re-export of doc hidden macro not showing up)
- #112014 (rustdoc: get unnormalized link destination for suggestions)
r? `@ghost`
`@rustbot` modify labels: rollup
Fix re-export of doc hidden macro not showing up
It's part of the follow-up of https://github.com/rust-lang/rust/pull/109697.
Re-exports of doc hidden macros should be visible. It was the only kind of re-export of doc hidden item that didn't show up.
r? `@notriddle`
Perform MIR type ops locally in new solver
The new solver already does caching, and it's generally more correct to be using the infcx of the MIR typeck (which has the defining anchor set correctly and has already initialized all the opaques from HIR typeck).
This is based on #111918 so look at the final 3 commits.
This actually causes some tests to go from passing to failing, and failing to passing. Here's the full diff: https://www.diffchecker.com/hB4bh1A9/
Putting this up for exposure mostly.
r? `@lcnr`
Add #[inline] to array TryFrom impls
I was looking into https://github.com/rust-lang/rust/issues/111959 and I realized we don't have these. They seem like an uncontroversial addition.
IMO this PR does not fix that issue. I think the bad codegen is being caused by some underlying deeper problem but this change might cause the MIR inliner to paper over it in this specific case.
r? `@thomcc`
