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This moves all LLVM intrinsic handling out of the regular call path for cg_gcc and makes it easier to hook into this code for future cg_llvm changes.
…acro_transparency`
It's described as a "backwards compatibility hack to keep the diff small". Removing it requires only a modest amount of churn, and the resulting code is clearer without the invisible derefs.
…ics-generation Simplify intrinsics generation
Regenerate intrinsics
Move LTO to OngoingCodegen::join This will make it easier to in the future move all this code to link_binary. Follow up to rust-lang#147810 Part of rust-lang/compiler-team#908
This is the conceptual opposite of the rust-cold calling convention and
is particularly useful in combination with the new `explicit_tail_calls`
feature.
For relatively tight loops implemented with tail calling (`become`) each
of the function with the regular calling convention is still responsible
for restoring the initial value of the preserved registers. So it is not
unusual to end up with a situation where each step in the tail call loop
is spilling and reloading registers, along the lines of:
foo:
push r12
; do things
pop r12
jmp next_step
This adds up quickly, especially when most of the clobberable registers
are already used to pass arguments or other uses.
I was thinking of making the name of this ABI a little less LLVM-derived
and more like a conceptual inverse of `rust-cold`, but could not come
with a great name (`rust-cold` is itself not a great name: cold in what
context? from which perspective? is it supposed to mean that the
function is rarely called?)
Fix segfault related to __builtin_unreachable with inline asm
…bilee
add `simd_splat` intrinsic
Add `simd_splat` which lowers to the LLVM canonical splat sequence.
```llvm
insertelement <N x elem> poison, elem %x, i32 0
shufflevector <N x elem> v0, <N x elem> poison, <N x i32> zeroinitializer
```
Right now we try to fake it using one of
```rust
fn splat(x: u32) -> u32x8 {
u32x8::from_array([x; 8])
}
```
or (in `stdarch`)
```rust
fn splat(value: $elem_type) -> $name {
#[derive(Copy, Clone)]
#[repr(simd)]
struct JustOne([$elem_type; 1]);
let one = JustOne([value]);
// SAFETY: 0 is always in-bounds because we're shuffling
// a simd type with exactly one element.
unsafe { simd_shuffle!(one, one, [0; $len]) }
}
```
Both of these can confuse the LLVM optimizer, producing sub-par code. Some examples:
- rust-lang#60637
- rust-lang#137407
- rust-lang#122623
- rust-lang#97804
---
As far as I can tell there is no way to provide a fallback implementation for this intrinsic, because there is no `const` way of evaluating the number of elements (there might be issues beyond that, too). So, I added implementations for all 4 backends.
Both GCC and const-eval appear to have some issues with simd vectors containing pointers. I have a workaround for GCC, but haven't yet been able to make const-eval work. See the comments below.
Currently this just adds the intrinsic, it does not actually use it anywhere yet.
…ochenkov
abi: add a rust-preserve-none calling convention
This is the conceptual opposite of the rust-cold calling convention and is particularly useful in combination with the new `explicit_tail_calls` feature.
For relatively tight loops implemented with tail calling (`become`) each of the function with the regular calling convention is still responsible for restoring the initial value of the preserved registers. So it is not unusual to end up with a situation where each step in the tail call loop is spilling and reloading registers, along the lines of:
foo:
push r12
; do things
pop r12
jmp next_step
This adds up quickly, especially when most of the clobberable registers are already used to pass arguments or other uses.
I was thinking of making the name of this ABI a little less LLVM-derived and more like a conceptual inverse of `rust-cold`, but could not come with a great name (`rust-cold` is itself not a great name: cold in what context? from which perspective? is it supposed to mean that the function is rarely called?)
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Looks like the subtree merge didn't have any issues this time. I don't see any changes of mine getting reverted. |
antoyo
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Feb 14, 2026
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@bors r+ p=1 |
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…cc_2026-02-14, r=GuillaumeGomez Update GCC subtree cc @antoyo r? ghost
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…cc_2026-02-14, r=GuillaumeGomez Update GCC subtree cc @antoyo r? ghost
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⌛ Testing commit 1f94802 with merge 42d651b... Workflow: https://github.com/rust-lang/rust/actions/runs/22024338905 |
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Auto build cancelled. Cancelled workflows: The next pull request likely to be tested is #152632. |
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…uwer Rollup of 7 pull requests Successful merges: - #152622 (Update GCC subtree) - #145024 (Optimize indexing slices and strs with inclusive ranges) - #151365 (UnsafePinned: implement opsem effects of UnsafeUnpin) - #152381 (Do not require `'static` for obtaining reflection information.) - #143575 (Remove named lifetimes in some `PartialOrd` & `PartialEq` `impl`s) - #152404 (tests: adapt align-offset.rs for InstCombine improvements in LLVM 23) - #152582 (rustc_query_impl: Use `ControlFlow` in `visit_waiters` instead of nested options)
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⌛ Testing commit 1f94802 with merge 7ea8b56... Workflow: https://github.com/rust-lang/rust/actions/runs/22026070155 |
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Auto build cancelled. Cancelled workflows: The next pull request likely to be tested is #152632. |
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…uwer Rollup of 7 pull requests Successful merges: - #152622 (Update GCC subtree) - #145024 (Optimize indexing slices and strs with inclusive ranges) - #151365 (UnsafePinned: implement opsem effects of UnsafeUnpin) - #152381 (Do not require `'static` for obtaining reflection information.) - #143575 (Remove named lifetimes in some `PartialOrd` & `PartialEq` `impl`s) - #152404 (tests: adapt align-offset.rs for InstCombine improvements in LLVM 23) - #152582 (rustc_query_impl: Use `ControlFlow` in `visit_waiters` instead of nested options)
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…uwer Rollup of 7 pull requests Successful merges: - rust-lang/rust#152622 (Update GCC subtree) - rust-lang/rust#145024 (Optimize indexing slices and strs with inclusive ranges) - rust-lang/rust#151365 (UnsafePinned: implement opsem effects of UnsafeUnpin) - rust-lang/rust#152381 (Do not require `'static` for obtaining reflection information.) - rust-lang/rust#143575 (Remove named lifetimes in some `PartialOrd` & `PartialEq` `impl`s) - rust-lang/rust#152404 (tests: adapt align-offset.rs for InstCombine improvements in LLVM 23) - rust-lang/rust#152582 (rustc_query_impl: Use `ControlFlow` in `visit_waiters` instead of nested options)
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cc @antoyo
r? ghost