rename erase_regions to erase_and_anonymize_regions
I find it consistently confusing that `erase_regions` does more than replacing regions with `'erased`. it also makes some code look real goofy to be writing manual folders to erase regions with a comment saying "we cant use erase regions" :> or code that re-calls erase_regions on types with regions already erased just to anonymize all the bound regions.
r? lcnr
idk how i feel about the name being almost twice as long now
This was done in #145740 and #145947. It is causing problems for people
using r-a on anything that uses the rustc-dev rustup package, e.g. Miri,
clippy.
This repository has lots of submodules and subtrees and various
different projects are carved out of pieces of it. It seems like
`[workspace.dependencies]` will just be more trouble than it's worth.
pub async fn impl is monomorphized when func itself is monomorphized
Implentation coroutine (`func::{closure#0}`) is monomorphized, when func itself is monomorphized.
Currently, when `pub async fn foo(..)` is exported from lib and used in several dependent crates, only 'header' function is monomorphized in the defining crate. 'header' function, returning coroutine object, is monomorphized, but the coroutine's poll function (which actually implements all the logic for the function) is not. In such situation, `func::{closure#0}` will be monomorphized in every dependency.
This PR adds monomorphization for `func::{closure#0}` (coroutine poll function), when func itself is monomorphized.
Simple test with one lib async function and ten dependent crates (executable) that use the function, shows 5-7% compilation time improvement (single-threaded).
Fix tail calls to `#[track_caller]` functions
We want `#[track_caller]` to be semver independent, i.e. it should not be a breaking change to add or remove it. Since it changes ABI of a function (adding an additional argument) we have to be careful to preserve this property when adding tail calls.
The only way to achieve this that I can see is:
- we forbid tail calls in functions which are marked with `#[track_caller]` (already implemented)
- tail-calling a `#[track_caller]` marked function downgrades the tail-call to a normal call (or equivalently tail-calls the shim made by fn def to fn ptr cast) (this pr)
Ideally the downgrade would be performed by a MIR pass, but that requires post mono MIR opts (cc ```@saethlin,``` rust-lang/rust#131650). For now I've changed code in cg_ssa to accomodate this behaviour (+ added a hack to mono collector so that the shim is actually generated)
Additionally I added a lint, although I don't think it's strictly necessary.
Alternative to rust-lang/rust#144762 (and thus closesrust-lang/rust#144762)
Fixes https://github.com/rust-lang/rust/issues/144755
Ensure we codegen the main fn
This fixes two bugs. The one that was identified in the linked issue is that when we have a `main` function, mono collection didn't consider it as an extra collection root.
The other is that since CGU partitioning doesn't know about the call edges between the entrypoint functions, naively it can put them in different CGUs and mark them all as internal. Which would result in LLVM just deleting all of them. There was an existing hack to exclude `lang = "start"` from internalization, which I've extended to include `main`.
Fixes https://github.com/rust-lang/rust/issues/144052
Insert checks for enum discriminants when debug assertions are enabled
Similar to the existing null-pointer and alignment checks, this checks for valid enum discriminants on creation of enums through unsafe transmutes. Essentially this sanitizes patterns like the following:
```rust
let val: MyEnum = unsafe { std::mem::transmute<u32, MyEnum>(42) };
```
An extension of this check will be done in a follow-up that explicitly sanitizes for extern enum values that come into Rust from e.g. C/C++.
This check is similar to Miri's capabilities of checking for valid construction of enum values.
This PR is inspired by saethlin@'s PR
https://github.com/rust-lang/rust/pull/104862. Thank you so much for keeping this code up and the detailed comments!
I also pair-programmed large parts of this together with vabr-g@.
r? `@saethlin`
Stop collecting unmentioned constants
This avoids generating useless dead LLVM IR. This appears to have regressed and/or been introduced in rust-lang/rust#53821 (unfortunately a very large PR - I don't see any direct discussion there of this particular change), but as far as I can tell is at least no longer necessary -- or we lack test coverage -- because none of our UI tests indicate diagnostics regressions. The adjusted codegen-units test has comments explicitly noting that these items should *not* be collected ("These are not referenced, so they do not produce mono-items").
I noticed this while looking at libcore LLVM IR we generate, which contained dead code references to the NOOP Waker item, which is never used inside libcore. Producing LLVM IR for it during libcore's compilation, only for that IR to get deleted by LLVM as unused, isn't useful. Note that the IR is generally all marked internal, too.
Similar to the existing nullpointer and alignment checks, this checks
for valid enum discriminants on creation of enums through unsafe
transmutes. Essentially this sanitizes patterns like the following:
```rust
let val: MyEnum = unsafe { std::mem::transmute<u32, MyEnum>(42) };
```
An extension of this check will be done in a follow-up that explicitly
sanitizes for extern enum values that come into Rust from e.g. C/C++.
This check is similar to Miri's capabilities of checking for valid
construction of enum values.
This PR is inspired by saethlin@'s PR
https://github.com/rust-lang/rust/pull/104862. Thank you so much for
keeping this code up and the detailed comments!
I also pair-programmed large parts of this together with vabr-g@.
Since 122662 this no longer gets used in vtables, so we're safe to fully
drop generating these empty functions. Those are eventually cleaned up
by LLVM, but it's wasteful to produce them in the first place.
This also adds a missing test for fn-ptr casts, which do still need to
generate no-op drop glue. It's possible a future optimization could
point all of those at the same drop glue (e.g., for *mut ()) rather than
for each separate type, but that would require extra work for CFI and
isn't particularly easy to do anyway.
Limit the size of cgu names when using the `-Zhuman-readable-cgu-name…
…s` option
Prior to this change, cgu names could be generated which would result in filenames longer than the limit imposed by the OS.
Replace ad-hoc ABI "adjustments" with an `AbiMap` to `CanonAbi`
Our `conv_from_spec_abi`, `adjust_abi`, and `is_abi_supported` combine to give us a very confusing way of reasoning about what _actual_ calling convention we want to lower our code to and whether we want to compile the resulting code at all. Instead of leaving this code as a miniature adventure game in which someone tries to combine stateful mutations into a Rube Goldberg machine that will let them escape the maze and arrive at the promised land of codegen, we let `AbiMap` devour this complexity. Once you have an `AbiMap`, you can answer which `ExternAbi`s will lower to what `CanonAbi`s (and whether they will lower at all).
Removed:
- `conv_from_spec_abi` replaced by `AbiMap::canonize_abi`
- `adjust_abi` replaced by same
- `Conv::PreserveAll` as unused
- `Conv::Cold` as unused
- `enum Conv` replaced by `enum CanonAbi`
target-spec.json changes:
- If you have a target-spec.json then now your "entry-abi" key will be specified in terms of one of the `"{abi}"` strings Rust recognizes, e.g.
```json
"entry-abi": "C",
"entry-abi": "win64",
"entry-abi": "aapcs",
```
make `rustc_attr_parsing` less dominant in the rustc crate graph
It has/had a glob re-export of `rustc_attr_data_structures`, which is a crate much lower in the graph, and a lot of crates were using it *just* (or *mostly*) for that re-export, while they can rely on `rustc_attr_data_structures` directly.
Previous graph:
Graph with this PR:
The first commit keeps the re-export, and just changes the dependency if possible. The second commit is the "breaking change" which removes the re-export, and "explicitly" adds the `rustc_attr_data_structures` dependency where needed. It also switches over some src/tools/*.
The second commit is actually a lot more involved than I expected. Please let me know if it's a better idea to back it out and just keep the first commit.
Stage0 bootstrap update
This PR [follows the release process](https://forge.rust-lang.org/release/process.html#master-bootstrap-update-tuesday) to update the stage0 compiler.
The only thing of note is 58651d1b31, which was flagged by clippy as a correctness fix. I think allowing that lint in our case makes sense, but it's worth to have a second pair of eyes on it.
r? `@Mark-Simulacrum`
Previously `-Zprint-mono-items` would override the mono item collection
strategy. When debugging one doesn't want to change the behaviour, so
this was counter productive. Additionally, the produced behaviour was
artificial and might never arise without using the option in the first
place (`-Zprint-mono-items=eager` without `-Clink-dead-code`). Finally,
the option was incorrectly marked as `UNTRACKED`.
Resolve those issues, by turning `-Zprint-mono-items` into a boolean
flag that prints results of mono item collection without changing the
behaviour of mono item collection.
For codegen-units test incorporate `-Zprint-mono-items` flag directly
into compiletest tool.
Test changes are mechanical. `-Zprint-mono-items=lazy` was removed
without additional changes, and `-Zprint-mono-items=eager` was turned
into `-Clink-dead-code`. Linking dead code disables internalization, so
tests have been updated accordingly.
While profiling Zed's dev build I've noticed that while most of the time `upstream_monomorphizations` takes a lot of time in monomorpization_collector, in some cases (e.g. build of `editor` itself)
the rest of monomorphization_collector_graph_walk dominates it. Most of the time is spent in collect_items_rec.
This PR aims to reduce the number of locks taking place; instead of locking output MonoItems once per children of current node, we do so once per *parent*. We also get to reuse locks for mentioned and used items.
While this commit does not reduce Wall time of Zed's build, it does shave off `cargo build -j1` from 43s to 41.5s.
Make #![feature(let_chains)] bootstrap conditional in compiler/
Let chains have been stabilized recently in #132833, so we can remove the gating from our uses in the compiler (as the compiler uses edition 2024).
make abi_unsupported_vector_types a hard error
Fixes https://github.com/rust-lang/rust/issues/116558 by completing the transition; see that issue for context. The lint was introduced with Rust 1.84 and this has been shown in cargo's future breakage reports since Rust 1.85, released 6 weeks ago, and so far we got 0 complaints by users. There's not even a backlink on the tracking issue. We did a [crater run](https://github.com/rust-lang/rust/pull/127731#issuecomment-2286736295) when the lint was originally added and found no breakage. So I don't think we need another crater run now, but I can do one if the team prefers that.
https://github.com/rust-lang/rust/issues/131800 is done, so for most current targets (in particular, all tier 1 and tier 2 targets) we have the information to implement this check (modulo the targets where we don't properly support SIMD vectors yet, see the sub-issues of https://github.com/rust-lang/rust/issues/116558). If a new target gets added in the future, it will default to reject all SIMD vector types until proper information is added, which is the default we want.
This will need approval by for `@rust-lang/lang.` Cc `@workingjubilee` `@veluca93`
try-job: test-various
try-job: armhf-gnu
try-job: dist-i586-gnu-i586-i686-musl
