Auto merge of #111836 - calebzulawski:target-feature-closure, r=worki… · rust-lang/rust@1c44af9 (original) (raw)
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- compiler/rustc_codegen_ssa/src
- ui/rfcs/rfc-2396-target_feature-11
3 files changed
lines changed
| Original file line number | Diff line number | Diff line change |
|---|---|---|
| @@ -501,7 +501,22 @@ fn codegen_fn_attrs(tcx: TyCtxt<'_>, did: LocalDefId) -> CodegenFnAttrs { | ||
| 501 | 501 | }); |
| 502 | 502 | |
| 503 | 503 | // #73631: closures inherit `#[target_feature]` annotations |
| 504 | -if tcx.features().target_feature_11 && tcx.is_closure(did.to_def_id()) { | |
| 504 | +// | |
| 505 | +// If this closure is marked `#[inline(always)]`, simply skip adding `#[target_feature]`. | |
| 506 | +// | |
| 507 | +// At this point, `unsafe` has already been checked and `#[target_feature]` only affects codegen. | |
| 508 | +// Emitting both `#[inline(always)]` and `#[target_feature]` can potentially result in an | |
| 509 | +// ICE, because LLVM errors when the function fails to be inlined due to a target feature | |
| 510 | +// mismatch. | |
| 511 | +// | |
| 512 | +// Using `#[inline(always)]` implies that this closure will most likely be inlined into | |
| 513 | +// its parent function, which effectively inherits the features anyway. Boxing this closure | |
| 514 | +// would result in this closure being compiled without the inherited target features, but this | |
| 515 | +// is probably a poor usage of `#[inline(always)]` and easily avoided by not using the attribute. | |
| 516 | +if tcx.features().target_feature_11 | |
| 517 | + && tcx.is_closure(did.to_def_id()) | |
| 518 | + && codegen_fn_attrs.inline != InlineAttr::Always | |
| 519 | +{ | |
| 505 | 520 | let owner_id = tcx.parent(did.to_def_id()); |
| 506 | 521 | if tcx.def_kind(owner_id).has_codegen_attrs() { |
| 507 | 522 | codegen_fn_attrs |
| Original file line number | Diff line number | Diff line change |
|---|---|---|
| @@ -0,0 +1,33 @@ | ||
| 1 | +// only-x86_64 | |
| 2 | +// compile-flags: -Copt-level=3 | |
| 3 | + | |
| 4 | +#![crate_type = "lib"] | |
| 5 | +#![feature(target_feature_11)] | |
| 6 | + | |
| 7 | +#[cfg(target_arch = "x86_64")] | |
| 8 | +use std::arch::x86_64::*; | |
| 9 | + | |
| 10 | +// CHECK-LABEL: @with_avx | |
| 11 | +#[no_mangle] | |
| 12 | +#[cfg(target_arch = "x86_64")] | |
| 13 | +#[target_feature(enable = "avx")] | |
| 14 | +fn with_avx(x: __m256) -> __m256 { | |
| 15 | +// CHECK: fadd | |
| 16 | +let add = { | |
| 17 | +#[inline(always)] | |
| 18 | + |x, y | |
| 19 | +}; | |
| 20 | +add(x, x) | |
| 21 | +} | |
| 22 | + | |
| 23 | +// CHECK-LABEL: @without_avx | |
| 24 | +#[no_mangle] | |
| 25 | +#[cfg(target_arch = "x86_64")] | |
| 26 | +unsafe fn without_avx(x: __m256) -> __m256 { | |
| 27 | +// CHECK-NOT: fadd | |
| 28 | +let add = { | |
| 29 | +#[inline(always)] | |
| 30 | + |x, y | |
| 31 | +}; | |
| 32 | +add(x, x) | |
| 33 | +} |
| Original file line number | Diff line number | Diff line change |
|---|---|---|
| @@ -0,0 +1,18 @@ | ||
| 1 | +// Tests #108655: closures in `#[target_feature]` functions can still be marked #[inline(always)] | |
| 2 | + | |
| 3 | +// check-pass | |
| 4 | +// revisions: mir thir | |
| 5 | +// [thir]compile-flags: -Z thir-unsafeck | |
| 6 | +// only-x86_64 | |
| 7 | + | |
| 8 | +#![feature(target_feature_11)] | |
| 9 | + | |
| 10 | +#[target_feature(enable = "avx")] | |
| 11 | +pub unsafe fn test() { | |
| 12 | +({ | |
| 13 | +#[inline(always)] | |
| 14 | +move | | |
| 15 | +})(); | |
| 16 | +} | |
| 17 | + | |
| 18 | +fn main() {} |