do not ICE when return type includes unconstrained anon region
It turns out that this *can* happen after all, if the region is only
used in projections from the input types.
Fixes https://github.com/rust-lang/rust/issues/47511
r? @eddyb
[perf] Use std based dedup in projection
Unstable sort was added recently, and the code that is being modified is 3 years old. As quicksort doesn't allocate it will likely perform as well as, or better than linear search.
I didn't benchmark. Have a perf run.
Teach rustc about DW_AT_noreturn and a few more DIFlags
We achieve two small things with this PR:
1. We provide definitions for a few additional llvm debuginfo flags
1. We _use_ one of these new flags, `FlagNoReturn`, and add it to debuginfo for functions with the never return type (`!`).
This commit changes the ABI of SIMD types in the "Rust" ABI to unconditionally
be passed via pointers instead of being passed as immediates. This should fix a
longstanding issue, #44367, where SIMD-using programs ended up showing very odd
behavior at runtime because the ABI between functions was mismatched.
As a bit of a recap, this is sort of an LLVM bug and sort of an LLVM feature
(today's behavior). LLVM will generate code for a function solely looking at the
function it's generating, including calls to other functions. Let's then say
you've got something that looks like:
```llvm
define void @foo() { ; no target features enabled
call void @bar(<i64 x 4> zeroinitializer)
ret void
}
define void @bar(<i64 x 4>) #0 { ; enables the AVX feature
...
}
```
LLVM will codegen the call to `bar` *without* using AVX registers becauase `foo`
doesn't have access to these registers. Instead it's generated with emulation
that uses two 128-bit registers. The `bar` function, on the other hand, will
expect its argument in an AVX register (as it has AVX enabled). This means we've
got a codegen problem!
Comments on #44367 have some more contexutal information but the crux of the
issue is that if we want SIMD to work in general we'll need to ensure that
whenever a function calls another they ABI of the arguments being passed is in
agreement.
One possible solution to this would be to insert "shim functions" where whenever
a `target_feature` mismatch is detected the compiler inserts a shim function
where you pass arguments via memory to the shim and then the shim loads the
values and calls the target function (where the shim and the target have the
same target features enabled). This unfortunately is quite nontrivial to
implement in rustc today (especially when accounting for function pointers and
such).
This commit takes a different solution, *always* passing SIMD arguments through
memory instead of passing as immediates. This strategy solves the problem at the
LLVM layer because the ABI between two functions never uses SIMD registers. This
also shouldn't be a hit to performance because SIMD performance is thought to
often rely on inlining anyway, where a `call` instruction, even if using SIMD
registers, would be disastrous to performance regardless. LLVM should then be
more than capable of fixing all our memory usage to use registers instead after
enough inlining has been performed.
Note that there's a few caveats to this commit though:
* The "platform intrinsic" ABI is omitted from "always pass via memory". This
ABI is used to define intrinsics like `simd_shuffle4` where LLVM and rustc
need to have the arguments as an immediate.
* Additionally this commit does *not* fix the `extern` ("C") ABI. This means
that the bug in #44367 can still happen when using non-Rust-ABI functions. My
hope is that before stabilization we can ban and/or warn about SIMD types in
these functions (as AFAIK there's not much motivation to belong there anyway),
but I'll leave that for a later commit and if this is merged I'll file a
follow-up issue.
All in all this...
Closes#44367
Fix type inhabitedness check for arrays
Arrays of uninhabited types were considered to also be uninhabited if
their length had not been evaluated, causing unsoundness.
Fixes#47563.
r? @eddyb
Add ./x.py check src/{libstd,libtest,librustc}
This currently only supports a limited subset of the full compilation,
but is likely 90% of what people will want and is possible without
building a full compiler (and also building LLVM). In theory, this means
that contributors who don't want to build LLVM now have an easy way to
compile locally, though running tests won't work.
Fix no_integrated_as option to work with new codegen architecture.
Old implementation called the assembler once per crate, but we need to call
it for each object file instead, because a single crate can now have more
than one object file.
This patch fixes issue #45836 (Can't compile core for msp430 in release mode)
This change can be tested on x86_64 using
```sh
export RUSTFLAGS="-C no_integrated_as -C save_temps"
```
r? @alexcrichton
cc @japaric
rustc_trans: ignore trailing padding larger than 8 bytes.
Fixes#45662 by ignoring a missing second register component, as it could be entirely padding.
rustc_trans: take into account primitives larger than 8 bytes.
Fixes#38763 by marking all "eightbytes" covered by a primitive appropriately, not just the first.
Add CGU size heuristic for partitioning
This addresses the concern of #47316 by estimating CGU size based on
the size of its MIR. Looking at the size estimate differences for a
small selection of crates, this heuristic produces different orderings,
which should more accurately reflect optimisation time. (Fixes #47316.)
r? @michaelwoerister
Fix spans in unused import lint for nested groups
This fixes an inconsistency for empty nested groups, and adds a test for all the possible cases of the lint.
```
warning: unused imports: `*`, `Foo`, `baz::{}`, `foobar::*`
--> test.rs:16:11
|
16 | use foo::{Foo, bar::{baz::{}, foobar::*}, *};
| ^^^ ^^^^^^^ ^^^^^^^^^ ^
|
= note: #[warn(unused_imports)] on by default
warning: unused import: `*`
--> test.rs:17:24
|
17 | use foo::bar::baz::{*, *};
| ^
warning: unused import: `use foo::{};`
--> test.rs:18:1
|
18 | use foo::{};
| ^^^^^^^^^^^^
```
cc #44494
Fix into() cast paren check precedence
As discussed in #47699 the logic for determining if an expression needs parenthesis when suggesting an `.into()` cast is incorrect. Two broken examples from nightly are:
```
error[E0308]: mismatched types
--> main.rs:4:10
|
4 | test(foo as i8);
| ^^^^^^^^^ expected i32, found i8
help: you can cast an `i8` to `i32`, which will sign-extend the source value
|
4 | test(foo as i8.into());
|
```
```
error[E0308]: mismatched types
--> main.rs:4:10
|
4 | test(*foo);
| ^^^^ expected i32, found i8
help: you can cast an `i8` to `i32`, which will sign-extend the source value
|
4 | test(*foo.into());
|
```
As suggested by @petrochenkov switch the precedence check to `PREC_POSTFIX`. This catches both `as` and unary operators. Fixes#47699.
r? @petrochenkov
Remove workarounds for cc 1.0.3.
Now that the Rust codebase depends on cc 1.0.4, there is no longer any
need to specify a compiler for CloudABI manually. Cargo will
automatically call into the right compiler executable.
Remove broken redundant backtrace hint
When the compiler driver panics it attempts to show a hint about using `RUST_BACKTRACE`. However, the logic is currently reversed to the hint is only shown if `RUST_BACKTRACE` is **already** set:
```shell
> RUST_BACKTRACE=1 rustc /dev/null --crate-type proc-macro
error: internal compiler error: unexpected panic
...
note: run with `RUST_BACKTRACE=1` for a backtrace
thread 'rustc' panicked at 'attempt to subtract with overflow', librustc_errors/emitter.rs:287:49
note: Some details are omitted, run with `RUST_BACKTRACE=full` for a verbose backtrace.
> RUST_BACKTRACE=0 rustc /dev/null --crate-type proc-macro
error: internal compiler error: unexpected panic
...
thread 'rustc' panicked at 'attempt to subtract with overflow', librustc_errors/emitter.rs:287:49
note: Run with `RUST_BACKTRACE=1` for a backtrace.
```
As the `panic` itself already has a working `RUST_BACKTRACE` hint just remove the broken duplicate hint entirely.
On missing method do not suggest private traits
When encountering a method call for an ADT that doesn't have any
implementation of it, we search for traits that could be implemented
that do have that method. Filter out private non-local traits that would
not be able to be implemented.
This doesn't account for public traits that are in a private scope, but
works as a first approximation and is a more correct behavior than the
current one.
Fix#45781.
The comment for why cloning exists doesn't actually apply for wasm today and
apparently cloning is causing subtle bugs in LLVM, so let's just avoid it
altogether. More specifically after we emit the assembly for the wasm target we
don't actually use the module again, so there's no need to keep both around.
This seemed to be causing some scary verifier assertions in LLVM which seemed to
be uncovered by presumably (?) buggy behavior. Let's just avoid it for now and
make the wasm target slightly more lean in the process.
It looks like LLVM also removed it in llvm-mirror/llvm@f45adc29d in favor of the
name "GNU64". This was added in the thought that we'd need such a variant when
adding mips64 support but we ended up not needing it! For now let's just
removing the various support on the Rust side of things.
Looks like they did some refactoring of flags in the backend and this should
catch us up! The "unsafe algebra" boolean has been split into a number of
boolean flags for various operations, and this updates to use the `setFast`
function which should hopefully have the same behavior as before.
This was updated in llvm-mirror/llvm@00e900afd
LLVM has since removed the `CodeModel::Default` enum value in favor of an
`Optional` implementationg throughout LLVM. Let's mirror the same change in Rust
and update the various bindings we call accordingly.
Removed in llvm-mirror/llvm@9aafb854c
