This commit is the final step in the journey of renaming the historical
`wasm32-wasi` target in the Rust compiler to `wasm32-wasip1`. Various
steps in this journey so far have been:
* 2023-04-03: rust-lang/compiler-team#607 - initial proposal for this rename
* 2024-11-27: rust-lang/compiler-team#695 - amended schedule/procedure for rename
* 2024-01-29: rust-lang/rust#120468 - initial introduction of `wasm32-wasip1`
* 2024-06-18: rust-lang/rust#126662 - warn on usage of `wasm32-wasi`
* 2024-11-08: this PR - remove the `wasm32-wasi` target
The full transition schedule is in [this comment][comment] and is
summarized with:
* 2024-05-02: Rust 1.78 released with `wasm32-wasip1` target
* 2024-09-05: Rust 1.81 released warning on usage of `wasm32-wasi`
* 2025-01-09: Rust 1.84 to be released without the `wasm32-wasi` target
This means that support on stable for the replacement target of
`wasm32-wasip1` has currently been available for 6 months. Users have
already seen warnings on stable for 2 months about usage of
`wasm32-wasi` and stable users have another 2 months of warnings before
the target is removed from stable.
This commit is intended to be the final step in this transition so the
source tree should no longer mention `wasm32-wasi` except in historical
reference to the older name of the `wasm32-wasip1` target.
[comment]: https://github.com/rust-lang/rust/pull/120468#issuecomment-1977878747
AddressSanitizer adds instrumentation to global variables unless the
[`no_sanitize_address`](https://llvm.org/docs/LangRef.html#global-attributes)
attribute is set on them.
This commit extends the existing `#[no_sanitize(address)]` attribute to
set this; previously it only had the desired effect on functions.
Add a Few Codegen Tests
Closes#86109Closes#64219
Those issues somehow got fixed over time.
So, this PR adds a couple of codegen tests to ensure we don't regress in the future.
Mark `simplify_aggregate_to_copy` mir-opt as unsound
Mark the `simplify_aggregate_to_copy` mir-opt added in #128299 as unsound as it seems to miscompile the MCVE reported in https://github.com/rust-lang/rust/issues/132353. The mir-opt can be re-enabled once this case is fixed.
```rs
fn pop_min(mut score2head: Vec<Option<usize>>) -> Option<usize> {
loop {
if let Some(col) = score2head[0] {
score2head[0] = None;
return Some(col);
}
}
}
fn main() {
let min = pop_min(vec![Some(1)]);
println!("min: {:?}", min);
// panic happens here on beta in release mode
// but not in debug mode
min.unwrap();
}
```
This MCVE is included as a `run-pass` ui regression test in the first commit. I built the ui test with a nightly manually, and can reproduce the behavioral difference with `-C opt-level=0` and `-C opt-level=1`. Locally, this ui test will fail unless it was run on a compiler built with the second commit marking the mir-opt as unsound thus disabling it by default.
This PR **partially reverts** commit e7386b3, reversing changes made to 02b1be1. The mir-opt implementation is just marked as unsound but **not** reverted to make reland reviews easier. Test changes are **reverted if they were not pure additions**. Tests added by the original PR received `-Z unsound-mir-opts` compile-flags.
cc `@DianQK` `@cjgillot` (PR author and reviewer of #128299)
Add a new 'pc' option to -Z branch-protection for aarch64 that
enables the use of PC as a diversifier in PAC branch protection code.
When the pauth-lr target feature is enabled in combination
with -Z branch-protection=pac-ret,pc, the new 9.5-a instructions
(pacibsppc, retaasppc, etc) will be generated.
Rename Receiver -> LegacyReceiver
As part of the "arbitrary self types v2" project, we are going to replace the current `Receiver` trait with a new mechanism based on a new, different `Receiver` trait.
This PR renames the old trait to get it out the way. Naming is hard. Options considered included:
* HardCodedReceiver (because it should only be used for things in the standard library, and hence is sort-of hard coded)
* LegacyReceiver
* TargetLessReceiver
* OldReceiver
These are all bad names, but fortunately this will be temporary. Assuming the new mechanism proceeds to stabilization as intended, the legacy trait will be removed altogether.
Although we expect this trait to be used only in the standard library, we suspect it may be in use elsehwere, so we're landing this change separately to identify any surprising breakages.
It's known that this trait is used within the Rust for Linux project; a patch is in progress to remove their dependency.
This is a part of the arbitrary self types v2 project,
https://github.com/rust-lang/rfcs/pull/3519https://github.com/rust-lang/rust/issues/44874
r? `@wesleywiser`
Set `signext` or `zeroext` for integer arguments on RISC-V and LoongArch64
This PR contains 3 commits:
- the first one introduces a new function `adjust_for_rust_abi` in `rustc_target`, and moves the x86 specific adjustment code into it;
- the second one adds RISC-V specific adjustment code into it, which sets `signext` or `zeroext` attribute for integer arguments.
- **UPDATE**: added the 3rd commit to apply the same adjustment for LoongArch64.
Optimize `Rc<T>::default`
The missing piece of https://github.com/rust-lang/rust/pull/131460.
Also refactored `Arc<T>::default` by using a safe `NonNull::from(Box::leak(_))` to replace the unnecessarily unsafe call to `NonNull::new_unchecked(Box::into_raw(_))`. The remaining unsafety is coming from `[Rc|Arc]::from_inner`, which is safe from the construction of `[Rc|Arc]Inner`.
x86-32 float return for 'Rust' ABI: treat all float types consistently
This helps with https://github.com/rust-lang/rust/issues/131819: for our own ABI on x86-32, we want to *never* use the float registers. The previous logic only considered F32 and F64, but skipped F16 and F128. So I made the logic just apply to all float types.
try-job: i686-gnu
try-job: i686-gnu-nopt
As part of the "arbitrary self types v2" project, we are going to
replace the current `Receiver` trait with a new mechanism based on a
new, different `Receiver` trait.
This PR renames the old trait to get it out the way. Naming is hard.
Options considered included:
* HardCodedReceiver (because it should only be used for things in the
standard library, and hence is sort-of hard coded)
* LegacyReceiver
* TargetLessReceiver
* OldReceiver
These are all bad names, but fortunately this will be temporary.
Assuming the new mechanism proceeds to stabilization as intended, the
legacy trait will be removed altogether.
Although we expect this trait to be used only in the standard library,
we suspect it may be in use elsehwere, so we're landing this change
separately to identify any surprising breakages.
It's known that this trait is used within the Rust for Linux project; a
patch is in progress to remove their dependency.
This is a part of the arbitrary self types v2 project,
https://github.com/rust-lang/rfcs/pull/3519https://github.com/rust-lang/rust/issues/44874
r? @wesleywiser
Always specify `llvm_abiname` for RISC-V targets
For RISC-V targets, when `llvm_abiname` is not specified LLVM will infer the ABI from the target features, causing #116344 to occur. This PR adds the correct `llvm_abiname` to all RISC-V targets where it is missing (which are all soft-float targets), and adds a test to prevent future RISC-V targets from accidentally omitting `llvm_abiname`. The only affect of this PR is that `-Ctarget-feature=+f` (or similar) will no longer affect the ABI on the modified targets.
<!-- homu-ignore:start -->
r? `@RalfJung`
<!--- homu-ignore:end -->
rust_for_linux: -Zregparm=<N> commandline flag for X86 (#116972)
Command line flag `-Zregparm=<N>` for X86 (32-bit) for rust-for-linux: https://github.com/rust-lang/rust/issues/116972
Implemented in the similar way as fastcall/vectorcall support (args are marked InReg if fit).
Return values larger than 2 registers using a return area pointer
LLVM and Cranelift disagree about how to return values that don't fit in the registers designated for return values. LLVM will force the entire return value to be passed by return area pointer, while Cranelift will look at each IR level return value independently and decide to pass it in a register or not, which would result in the return value being passed partially in registers and partially through a return area pointer.
While Cranelift may need to be fixed as the LLVM behavior is generally more correct with respect to the surface language, forcing this behavior in rustc itself makes it easier for other backends to conform to the Rust ABI and for the C ABI rustc already handles this behavior anyway.
In addition LLVM's decision to pass the return value in registers or using a return area pointer depends on how exactly the return type is lowered to an LLVM IR type. For example `Option<u128>` can be lowered as `{ i128, i128 }` in which case the x86_64 backend would use a return area pointer, or it could be passed as `{ i32, i128 }` in which case the x86_64 backend would pass it in registers by taking advantage of an LLVM ABI extension that allows using 3 registers for the x86_64 sysv call conv rather than the officially specified 2 registers.
This adjustment is only necessary for the Rust ABI as for other ABI's the calling convention implementations in rustc_target already ensure any return value which doesn't fit in the available amount of return registers is passed in the right way for the current target.
Helps with https://github.com/rust-lang/rustc_codegen_cranelift/issues/1525
cc https://github.com/bytecodealliance/wasmtime/issues/9250
Avoid superfluous UB checks in `IndexRange`
`IndexRange::len` is justified as an overall invariant, and
`take_prefix` and `take_suffix` are justified by local branch
conditions. A few more UB-checked calls remain in cases that are only
supported locally by `debug_assert!`, which won't do anything in
distributed builds, so those UB checks may still be useful.
We generally expect core's `#![rustc_preserve_ub_checks]` to optimize
away in user's release builds, but the mere presence of that extra code
can sometimes inhibit optimization, as seen in #131563.
llvm/llvm-project#91101 propagates range information across inlining,
resulting in more metadata in this test. Tolerate the range metadata if
it appears.
Support clobber_abi in MSP430 inline assembly
This supports `clobber_abi` which is one of the requirements of stabilization mentioned in #93335.
Refs: Section 3.2 "Register Conventions" in [MSP430 Embedded Application Binary Interface](https://www.ti.com/lit/an/slaa534a/slaa534a.pdf)
cc ``@cr1901``
r? ``@Amanieu``
``@rustbot`` label +O-msp430
`IndexRange::len` is justified as an overall invariant, and
`take_prefix` and `take_suffix` are justified by local branch
conditions. A few more UB-checked calls remain in cases that are only
supported locally by `debug_assert!`, which won't do anything in
distributed builds, so those UB checks may still be useful.
We generally expect core's `#![rustc_preserve_ub_checks]` to optimize
away in user's release builds, but the mere presence of that extra code
can sometimes inhibit optimization, as seen in #131563.
Use Default visibility for rustc-generated C symbol declarations
Non-default visibilities should only be used for definitions, not declarations, otherwise linking can fail.
This is based on https://github.com/rust-lang/rust/pull/123994.
Issue https://github.com/rust-lang/rust/issues/123427
When I changed `default-hidden-visibility` to `default-visibility` in https://github.com/rust-lang/rust/pull/130005, I updated all places in the code that used `default-hidden-visibility`, replicating the hidden-visibility bug to also happen for protected visibility.
Without this change, trying to build rustc with `-Z default-visibility=protected` fails with a link error.
This hack was intended to handle the case where `-Clto=thin` causes the
compiler to emit multiple output files (when producing LLVM-IR or assembly).
The hack only affects 4 tests, of which 3 are just meta-tests for the hack
itself. The one remaining test that motivated the hack currently doesn't even
need it!
(`tests/codegen/issues/issue-81408-dllimport-thinlto-windows.rs`)
Non-default visibilities should only be used for definitions, not
declarations, otherwise linking can fail.
Co-authored-by: Collin Baker <collinbaker@chromium.org>
LLVM and Cranelift disagree about how to return values that don't fit
in the registers designated for return values. LLVM will force the
entire return value to be passed by return area pointer, while
Cranelift will look at each IR level return value independently and
decide to pass it in a register or not, which would result in the
return value being passed partially in registers and partially through
a return area pointer.
While Cranelift may need to be fixed as the LLVM behavior is generally
more correct with respect to the surface language, forcing this
behavior in rustc itself makes it easier for other backends to conform
to the Rust ABI and for the C ABI rustc already handles this behavior
anyway.
In addition LLVM's decision to pass the return value in registers or
using a return area pointer depends on how exactly the return type is
lowered to an LLVM IR type. For example `Option<u128>` can be lowered
as `{ i128, i128 }` in which case the x86_64 backend would use a return
area pointer, or it could be passed as `{ i32, i128 }` in which case
the x86_64 backend would pass it in registers by taking advantage of an
LLVM ABI extension that allows using 3 registers for the x86_64 sysv
call conv rather than the officially specified 2 registers.
This adjustment is only necessary for the Rust ABI as for other ABI's
the calling convention implementations in rustc_target already ensure
any return value which doesn't fit in the available amount of return
registers is passed in the right way for the current target.
The `Box<T: Default>` impl currently calls `T::default()` before allocating
the `Box`.
Most `Default` impls are trivial, which should in theory allow
LLVM to construct `T: Default` directly in the `Box` allocation when calling
`<Box<T>>::default()`.
However, the allocation may fail, which necessitates calling `T's` destructor if it has one.
If the destructor is non-trivial, then LLVM has a hard time proving that it's
sound to elide, which makes it construct `T` on the stack first, and then copy it into the allocation.
Create an uninit `Box` first, and then write `T::default` into it, so that LLVM now only needs to prove
that the `T::default` can't panic, which should be trivial for most `Default` impls.
Add missing module flags for `-Zfunction-return=thunk-extern`
This fixes a bug in the `-Zfunction-return=thunk-extern` flag. The flag needs to be passed onto LLVM to ensure that functions such as `asan.module_ctor` and `asan.module_dtor` that are created internally in LLVM have the mitigation applied to them.
This was originally discovered [in the Linux kernel](https://lore.kernel.org/all/CANiq72myZL4_poCMuNFevtpYYc0V0embjSuKb7y=C+m3vVA_8g@mail.gmail.com/).
Original flag PR: #116892
PR for similar issue: #129373
Tracking issue: #116853
cc ``@ojeda``
r? ``@wesleywiser``
- fix for divergence
- fix error message
- fix another cranelift test
- fix some cranelift things
- don't set the NORETURN option for naked asm
- fix use of naked_asm! in doc comment
- fix use of naked_asm! in run-make test
- use `span_bug` in unreachable branch
Refactor the code in the `convert_while_ascii` helper function to make
it more suitable for auto-vectorization and also process the full ascii
prefix of the string. The generic case conversion logic will only be
invoked starting from the first non-ascii character.
The runtime on microbenchmarks with ascii-only inputs improves between
1.5x for short and 4x for long inputs on x86_64 and aarch64.
The new implementation also encapsulates all unsafe inside the
`convert_while_ascii` function.
Fixes#123712
Don't alloca for unused locals
We already have a concept of mono-unreachable basic blocks; this is primarily useful for ensuring that we do not compile code under an `if false`. But since we never gave locals the same analysis, a large local only used under an `if false` will still have stack space allocated for it.
There are 3 places we traverse MIR during monomorphization: Inside the collector, `non_ssa_locals`, and the walk to generate code. Unfortunately, https://github.com/rust-lang/rust/pull/129283#issuecomment-2297925578 indicates that we cannot afford the expense of tracking reachable locals during the collector's traversal, so we do need at least two mono-reachable traversals. And of course caching is of no help here because the benchmarks that regress are incr-unchanged; they don't do any codegen.
This fixes the second problem in https://github.com/rust-lang/rust/issues/129282, and brings us anther step toward `const if` at home.
Remove macOS 10.10 dynamic linker bug workaround
Rust's current minimum macOS version is 10.12, so the hack can be removed. This PR also updates the `remove_dir_all` docs to reflect that all supported macOS versions are protected against TOCTOU race conditions (the fallback implementation was already removed in #127683).
try-job: dist-x86_64-apple
try-job: dist-aarch64-apple
try-job: dist-apple-various
try-job: aarch64-apple
try-job: x86_64-apple-1
Update the minimum external LLVM to 18
With this change, we'll have stable support for LLVM 18 and 19.
For reference, the previous increase to LLVM 17 was #122649.
cc `@rust-lang/wg-llvm`
r? nikic
tests: add repr/transparent test for aarch64
Fixes#74396.
Moves `transparent-struct-ptr.rs` to `transparent-byval-struct-ptr.rs` and then adds a new `transparent-opaque-ptr.rs` for aarch64.
On LLVM 20, these instructions already get eliminated, which at least
partially satisfies a TODO. I'm not talented enough at using FileCheck
to try and constrain this further, but if we really want to we could
copy an LLVM 20 specific version of this test that would restore it to
being CHECK-NEXT: insertvalue ...
@rustbot label: +llvm-main
Do not request sanitizers for naked functions
Naked functions can only contain inline asm, so any instrumentation inserted by sanitizers is illegal. Don't request it.
Fixes https://github.com/rust-lang/rust/issues/129224.
Don't emit `expect`/`assume` in opt-level=0
LLVM does not make use of expect/assume calls in `opt-level=0`, so we can simplify IR by not emitting them in this case.
rustc_target: Add various aarch64 features
Add various aarch64 features already supported by LLVM and Linux.
Additionally include some comment fixes to ensure consistency of feature names with the Arm ARM.
Compiler support for features added to stdarch by https://github.com/rust-lang/stdarch/pull/1614.
Tracking issue for unstable aarch64 features is https://github.com/rust-lang/rust/issues/127764.
List of added features:
- FEAT_CSSC
- FEAT_ECV
- FEAT_FAMINMAX
- FEAT_FLAGM2
- FEAT_FP8
- FEAT_FP8DOT2
- FEAT_FP8DOT4
- FEAT_FP8FMA
- FEAT_HBC
- FEAT_LSE128
- FEAT_LSE2
- FEAT_LUT
- FEAT_MOPS
- FEAT_LRCPC3
- FEAT_SVE_B16B16
- FEAT_SVE2p1
- FEAT_WFxT
- FEAT_SME
- FEAT_SME_F16F16
- FEAT_SME_F64F64
- FEAT_SME_F8F16
- FEAT_SME_F8F32
- FEAT_SME_FA64
- FEAT_SME_I16I64
- FEAT_SME_LUTv2
- FEAT_SME2
- FEAT_SME2p1
- FEAT_SSVE_FP8DOT2
- FEAT_SSVE_FP8DOT4
- FEAT_SSVE_FP8FMA
FEAT_FPMR is added in the first commit and then removed in a separate one to highlight it being removed from upstream LLVM 19. The intention is for it to be detectable at runtime through stdarch but not have a corresponding Rust compile-time feature.
add repr to the allowlist for naked functions
Fixes#129412 (combining unstable features #90957 (`#![feature(naked_functions)]`) and #82232 (`#![feature(fn_align)]`)
Set the cfi-normalize-integers and kcfi-offset module flags when
Control-Flow Integrity sanitizers are used, so functions generated by
the LLVM backend use the same CFI/KCFI options as rustc.
cfi-normalize-integers tells LLVM to also use integer normalization
for generated functions when -Zsanitizer-cfi-normalize-integers is
used.
kcfi-offset specifies the number of prefix nops between the KCFI
type hash and the function entry when -Z patchable-function-entry is
used. Note that LLVM assumes all indirectly callable functions use the
same number of prefix NOPs with -Zsanitizer=kcfi.
Unconditionally allow shadow call-stack sanitizer for AArch64
It is possible to do so whenever `-Z fixed-x18` is applied.
cc ``@Darksonn`` for context
The reasoning is that, as soon as reservation on `x18` is forced through the flag `fixed-x18`, on AArch64 the option to instrument with [Shadow Call Stack sanitizer](https://clang.llvm.org/docs/ShadowCallStack.html) is then applicable regardless of the target configuration.
At the every least, we would like to relax the restriction on specifically `aarch64-unknonw-none`. For this option, we can include a documentation change saying that users of compiled objects need to ensure that they are linked to runtime with Shadow Call Stack instrumentation support.
Related: #121972
Rework MIR inlining debuginfo so function parameters show up in debuggers.
Line numbers of multiply-inlined functions were fixed in #114643 by using a single DISubprogram. That, however, triggered assertions because parameters weren't deduplicated. The "solution" to that in #115417 was to insert a DILexicalScope below the DISubprogram and parent all of the parameters to that scope. That fixed the assertion, but debuggers (including gdb and lldb) don't recognize variables that are not parented to the subprogram itself as parameters, even if they are emitted with DW_TAG_formal_parameter.
Consider the program:
```rust
use std::env;
#[inline(always)]
fn square(n: i32) -> i32 {
n * n
}
#[inline(never)]
fn square_no_inline(n: i32) -> i32 {
n * n
}
fn main() {
let x = square(env::vars().count() as i32);
let y = square_no_inline(env::vars().count() as i32);
println!("{x} == {y}");
}
```
When making a release build with debug=2 and rustc 1.82.0-nightly (8b3870784 2024-08-07)
```
(gdb) r
Starting program: /ephemeral/tmp/target/release/tmp [Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
Breakpoint 1, tmp::square () at src/main.rs:5
5 n * n
(gdb) info args
No arguments.
(gdb) info locals
n = 31
(gdb) c
Continuing.
Breakpoint 2, tmp::square_no_inline (n=31) at src/main.rs:10
10 n * n
(gdb) info args
n = 31
(gdb) info locals
No locals.
```
This issue is particularly annoying because it removes arguments from stack traces.
The DWARF for the inlined function looks like this:
```
< 2><0x00002132 GOFF=0x00002132> DW_TAG_subprogram
DW_AT_linkage_name _ZN3tmp6square17hc507052ff3d2a488E
DW_AT_name square
DW_AT_decl_file 0x0000000f /ephemeral/tmp/src/main.rs
DW_AT_decl_line 0x00000004
DW_AT_type 0x00001a56<.debug_info+0x00001a56>
DW_AT_inline DW_INL_inlined
< 3><0x00002142 GOFF=0x00002142> DW_TAG_lexical_block
< 4><0x00002143 GOFF=0x00002143> DW_TAG_formal_parameter
DW_AT_name n
DW_AT_decl_file 0x0000000f /ephemeral/tmp/src/main.rs
DW_AT_decl_line 0x00000004
DW_AT_type 0x00001a56<.debug_info+0x00001a56>
< 4><0x0000214e GOFF=0x0000214e> DW_TAG_null
< 3><0x0000214f GOFF=0x0000214f> DW_TAG_null
```
That DW_TAG_lexical_block inhibits every debugger I've tested from recognizing 'n' as a parameter.
This patch removes the additional lexical scope. Parameters can be easily deduplicated by a tuple of their scope and the argument index, at the trivial cost of taking a Hash + Eq bound on DIScope.
Line numbers of multiply-inlined functions were fixed in #114643 by using a
single DISubprogram. That, however, triggered assertions because parameters
weren't deduplicated. The "solution" to that in #115417 was to insert a
DILexicalScope below the DISubprogram and parent all of the parameters to that
scope. That fixed the assertion, but debuggers (including gdb and lldb) don't
recognize variables that are not parented to the subprogram itself as parameters,
even if they are emitted with DW_TAG_formal_parameter.
Consider the program:
use std::env;
fn square(n: i32) -> i32 {
n * n
}
fn square_no_inline(n: i32) -> i32 {
n * n
}
fn main() {
let x = square(env::vars().count() as i32);
let y = square_no_inline(env::vars().count() as i32);
println!("{x} == {y}");
}
When making a release build with debug=2 and rustc 1.82.0-nightly (8b3870784 2024-08-07)
(gdb) r
Starting program: /ephemeral/tmp/target/release/tmp
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
Breakpoint 1, tmp::square () at src/main.rs:5
5 n * n
(gdb) info args
No arguments.
(gdb) info locals
n = 31
(gdb) c
Continuing.
Breakpoint 2, tmp::square_no_inline (n=31) at src/main.rs:10
10 n * n
(gdb) info args
n = 31
(gdb) info locals
No locals.
This issue is particularly annoying because it removes arguments from stack traces.
The DWARF for the inlined function looks like this:
< 2><0x00002132 GOFF=0x00002132> DW_TAG_subprogram
DW_AT_linkage_name _ZN3tmp6square17hc507052ff3d2a488E
DW_AT_name square
DW_AT_decl_file 0x0000000f /ephemeral/tmp/src/main.rs
DW_AT_decl_line 0x00000004
DW_AT_type 0x00001a56<.debug_info+0x00001a56>
DW_AT_inline DW_INL_inlined
< 3><0x00002142 GOFF=0x00002142> DW_TAG_lexical_block
< 4><0x00002143 GOFF=0x00002143> DW_TAG_formal_parameter
DW_AT_name n
DW_AT_decl_file 0x0000000f /ephemeral/tmp/src/main.rs
DW_AT_decl_line 0x00000004
DW_AT_type 0x00001a56<.debug_info+0x00001a56>
< 4><0x0000214e GOFF=0x0000214e> DW_TAG_null
< 3><0x0000214f GOFF=0x0000214f> DW_TAG_null
That DW_TAG_lexical_block inhibits every debugger I've tested from recognizing
'n' as a parameter.
This patch removes the additional lexical scope. Parameters can be easily
deduplicated by a tuple of their scope and the argument index, at the trivial
cost of taking a Hash + Eq bound on DIScope.
const vector passed through to codegen
This allows constant vectors using a repr(simd) type to be propagated
through to the backend by reusing the functionality used to do a similar
thing for the simd_shuffle intrinsic
#118209
r? RalfJung
nontemporal_store: make sure that the intrinsic is truly just a hint
The `!nontemporal` flag for stores in LLVM *sounds* like it is just a hint, but actually, it is not -- at least on x86, non-temporal stores need very special treatment by the programmer or else the Rust memory model breaks down. LLVM still treats these stores as-if they were normal stores for optimizations, which is [highly dubious](https://github.com/llvm/llvm-project/issues/64521). Let's avoid all that dubiousness by making our own non-temporal stores be truly just a hint, which is possible on some targets (e.g. ARM). On all other targets, non-temporal stores become regular stores.
~~Blocked on https://github.com/rust-lang/stdarch/pull/1541 propagating to the rustc repo, to make sure the `_mm_stream` intrinsics are unaffected by this change.~~
Fixes https://github.com/rust-lang/rust/issues/114582
Cc `@Amanieu` `@workingjubilee`
fix: #128855 Ensure `Guard`'s `drop` method is removed at `opt-level=s` for `…
fix: #128855
…Copy` types
Added `#[inline]` to the `drop` method in the `Guard` implementation to ensure that the method is removed by the compiler at optimization level `opt-level=s` for `Copy` types. This change aims to align the method's behavior with optimization expectations and ensure it does not affect performance.
r? `@scottmcm`
This commit adds a new test file 'array-from_fn.rs' to the codegen test suite.
The test checks the behavior of std::array::from_fn under different optimization levels:
1. At opt-level=0 (debug build), it verifies that the core::array::Guard
is present in the generated code.
2. At opt-level=s (size optimization), it ensures that the Guard is
optimized out.
This test helps ensure that the compiler correctly optimizes array::from_fn
calls in release builds while maintaining safety checks in debug builds.
Rollup of 8 pull requests
Successful merges:
- #128221 (Add implied target features to target_feature attribute)
- #128261 (impl `Default` for collection iterators that don't already have it)
- #128353 (Change generate-copyright to generate HTML, with cargo dependencies included)
- #128679 (codegen: better centralize function declaration attribute computation)
- #128732 (make `import.vis` is immutable)
- #128755 (Integrate crlf directly into related test file instead via of .gitattributes)
- #128772 (rustc_codegen_ssa: Set architecture for object crate for 32-bit SPARC)
- #128782 (unused_parens: do not lint against parens around &raw)
r? `@ghost`
`@rustbot` modify labels: rollup
Rollup of 4 pull requests
Successful merges:
- #127574 (elaborate unknowable goals)
- #128141 (Set branch protection function attributes)
- #128315 (Fix vita build of std and forbid unsafe in unsafe in the os/vita module)
- #128339 ([rustdoc] Make the buttons remain when code example is clicked)
r? `@ghost`
`@rustbot` modify labels: rollup
Add `select_unpredictable` to force LLVM to use CMOV
Since https://reviews.llvm.org/D118118, LLVM will no longer turn CMOVs into branches if it comes from a `select` marked with an `unpredictable` metadata attribute.
This PR introduces `core::intrinsics::select_unpredictable` which emits such a `select` and uses it in the implementation of `binary_search_by`.
Set branch protection function attributes
Since LLVM 19, it is necessary to set not only module flags, but also function attributes for branch protection on aarch64. See e15d67cfc2 for the relevant LLVM change.
Fixes https://github.com/rust-lang/rust/issues/127829.
Since https://reviews.llvm.org/D118118, LLVM will no longer turn CMOVs
into branches if it comes from a `select` marked with an `unpredictable`
metadata attribute.
This PR introduces `core::intrinsics::select_unpredictable` which emits
such a `select` and uses it in the implementation of `binary_search_by`.
Delete `SimplifyArmIdentity` and `SimplifyBranchSame` tests
These two passes have already been deleted in #107256. I'm not sure why tidy didn't catch it.
As regression tests, I didn't delete `tests/ui/mir/issue-66851.rs` and `tests/ui/mir/simplify-branch-same.rs`.
r? compiler
Since LLVM 19, it is necessary to set not only module flags, but
also function attributes for branch protection on aarch64. See
e15d67cfc2
for the relevant LLVM change.
reenable some windows tests
Locally passing on `x86_64-pc-windows-msvc`, fingers crossed for `*-pc-windows-gnu`.
try-job: x86_64-msvc
try-job: x86_64-mingw
Ensure floats are returned losslessly by the Rust ABI on 32-bit x86
Solves #115567 for the (default) `"Rust"` ABI. When compiling for 32-bit x86, this PR changes the `"Rust"` ABI to return floats indirectly instead of in x87 registers (with the exception of single `f32`s, which this PR returns in general purpose registers as they are small enough to fit in one). No change is made to the `"C"` ABI as that ABI requires x87 register usage and therefore will need a different solution.
`-Z patchable-function-entry` works like `-fpatchable-function-entry`
on clang/gcc. The arguments are total nop count and function offset.
See MCP rust-lang/compiler-team#704
