bjoernager/rust
bjoernager/rust
1
Fork 0
Code Activity

Rollup merge of #78396 - josephlr:ermsb, r=petrochenkov

Browse source 
Add compiler support for LLVM's x86_64 ERMSB feature

This change is needed for compiler-builtins to check for this feature
when implementing memcpy/memset. See:
  https://github.com/rust-lang/compiler-builtins/pull/365

Without this change, the following code compiles, but does nothing:
```rust
#[cfg(target_feature = "ermsb")]
pub unsafe fn ermsb_memcpy() { ... }
```

The change just does compile-time detection. I think that runtime
detection will have to come in a follow-up CL to std-detect.

Like all the CPU feature flags, this just references #44839

Signed-off-by: Joe Richey <joerichey@google.com>
This commit is contained in:
Yuki Okushi 2020-10-27 08:45:24 +09:00 • committed by GitHub
commit 46b8e46fe1
No known key found for this signature in database
GPG key ID: 4AEE18F83AFDEB23
6 changed files with 6 additions and 1 deletions
Download patch file Download diff file Expand all files Collapse all files

1
compiler/rustc_feature/src/active.rs
View file

@ -243,6 +243,7 @@ declare_features! (
(active, rtm_target_feature, "1.35.0", Some(44839), None),
(active, f16c_target_feature, "1.36.0", Some(44839), None),
(active, riscv_target_feature, "1.45.0", Some(44839), None),
(active, ermsb_target_feature, "1.49.0", Some(44839), None),
// -------------------------------------------------------------------------
// feature-group-end: actual feature gates (target features)