diff options
| -rw-r--r-- | src/librustc_codegen_llvm/back/write.rs | 17 | ||||
| -rw-r--r-- | src/librustc_codegen_llvm/llvm_util.rs | 1 | ||||
| -rw-r--r-- | src/librustc_target/spec/wasm32_unknown_unknown.rs | 3 |
3 files changed, 15 insertions, 6 deletions
diff --git a/src/librustc_codegen_llvm/back/write.rs b/src/librustc_codegen_llvm/back/write.rs index 2373428d68c..c88a1809cab 100644 --- a/src/librustc_codegen_llvm/back/write.rs +++ b/src/librustc_codegen_llvm/back/write.rs @@ -171,13 +171,22 @@ pub fn target_machine_factory(sess: &Session, find_features: bool) None => llvm::CodeModel::None, }; - let singlethread = sess.target.target.options.singlethread; + let features = attributes::llvm_target_features(sess).collect::<Vec<_>>(); + let mut singlethread = sess.target.target.options.singlethread; + + // On the wasm target once the `atomics` feature is enabled that means that + // we're no longer single-threaded, or otherwise we don't want LLVM to + // lower atomic operations to single-threaded operations. + if singlethread && + sess.target.target.llvm_target.contains("wasm32") && + features.iter().any(|s| *s == "+atomics") + { + singlethread = false; + } let triple = SmallCStr::new(&sess.target.target.llvm_target); let cpu = SmallCStr::new(llvm_util::target_cpu(sess)); - let features = attributes::llvm_target_features(sess) - .collect::<Vec<_>>() - .join(","); + let features = features.join(","); let features = CString::new(features).unwrap(); let is_pie_binary = !find_features && is_pie_binary(sess); let trap_unreachable = sess.target.target.options.trap_unreachable; diff --git a/src/librustc_codegen_llvm/llvm_util.rs b/src/librustc_codegen_llvm/llvm_util.rs index 9fcc33d82cf..4f172c9f292 100644 --- a/src/librustc_codegen_llvm/llvm_util.rs +++ b/src/librustc_codegen_llvm/llvm_util.rs @@ -173,6 +173,7 @@ const MIPS_WHITELIST: &[(&str, Option<&str>)] = &[ const WASM_WHITELIST: &[(&str, Option<&str>)] = &[ ("simd128", Some("wasm_target_feature")), + ("atomics", Some("wasm_target_feature")), ]; /// When rustdoc is running, provide a list of all known features so that all their respective diff --git a/src/librustc_target/spec/wasm32_unknown_unknown.rs b/src/librustc_target/spec/wasm32_unknown_unknown.rs index 6c368e09003..c0455ceb839 100644 --- a/src/librustc_target/spec/wasm32_unknown_unknown.rs +++ b/src/librustc_target/spec/wasm32_unknown_unknown.rs @@ -36,8 +36,7 @@ pub fn target() -> Result<Target, String> { dll_suffix: ".wasm".to_string(), linker_is_gnu: false, - // A bit of a lie, but "eh" - max_atomic_width: Some(32), + max_atomic_width: Some(64), // Unwinding doesn't work right now, so the whole target unconditionally // defaults to panic=abort. Note that this is guaranteed to change in |