bjoernager/rust
bjoernager/rust
1
Fork 0
Code Issues Pull requests Activity

Updated the list of white-listed target features for x86

Browse source 
This PR both adds in-source documentation on what to look out for
when adding a new (X86) feature set and adds all that are detectable at run-time in Rust stable
as of 1.27.0.

This should only enable the use of the corresponding LLVM intrinsics.
Actual intrinsics need to be added separately in rust-lang/stdarch.

It also re-orders the run-time-detect test statements to be more consistent
with the actual list of intrinsics whitelisted and removes underscores not present
in the actual names (which might be mistaken as being part of the name)
This commit is contained in:
DevJPM 2020-10-25 16:53:25 +01:00
parent f392479de6
commit 9feb567399
3 changed files with 56 additions and 25 deletions
Download patch file Download diff file Expand all files Collapse all files

5
compiler/rustc_codegen_llvm/src/llvm_util.rs
View file

@ -137,6 +137,8 @@ pub fn time_trace_profiler_finish(file_name: &str) {
// WARNING: the features after applying `to_llvm_feature` must be known
// to LLVM or the feature detection code will walk past the end of the feature
// array, leading to crashes.
// To find a list of LLVM's names, check llvm-project/llvm/include/llvm/Support/*TargetParser.def
// where the * matches the architecture's name
pub fn to_llvm_feature<'a>(sess: &Session, s: &'a str) -> &'a str {
let arch = if sess.target.arch == "x86_64" { "x86" } else { &*sess.target.arch };
match (arch, s) {
@ -144,6 +146,9 @@ pub fn to_llvm_feature<'a>(sess: &Session, s: &'a str) -> &'a str {
("x86", "rdrand") => "rdrnd",
("x86", "bmi1") => "bmi",
("x86", "cmpxchg16b") => "cx16",
("x86", "avx512vaes") => "vaes",
("x86", "avx512gfni") => "gfni",
("x86", "avx512vpclmulqdq") => "vpclmulqdq",
("aarch64", "fp") => "fp-armv8",
("aarch64", "fp16") => "fullfp16",
(_, s) => s,