diff --git a/compiler/rustc_codegen_llvm/src/lib.rs b/compiler/rustc_codegen_llvm/src/lib.rs
index 6a86237d79e..805843e5863 100644
--- a/compiler/rustc_codegen_llvm/src/lib.rs
+++ b/compiler/rustc_codegen_llvm/src/lib.rs
@@ -10,6 +10,7 @@
#![feature(iter_intersperse)]
#![feature(let_chains)]
#![feature(never_type)]
+#![feature(impl_trait_in_assoc_type)]
#![recursion_limit = "256"]
#![allow(rustc::potential_query_instability)]
#![deny(rustc::untranslatable_diagnostic)]
diff --git a/compiler/rustc_codegen_llvm/src/llvm_util.rs b/compiler/rustc_codegen_llvm/src/llvm_util.rs
index a75c15ee4be..03be0654b50 100644
--- a/compiler/rustc_codegen_llvm/src/llvm_util.rs
+++ b/compiler/rustc_codegen_llvm/src/llvm_util.rs
@@ -16,7 +16,6 @@ use rustc_session::config::PrintRequest;
use rustc_session::Session;
use rustc_span::symbol::Symbol;
use rustc_target::spec::{MergeFunctions, PanicStrategy};
-use smallvec::{smallvec, SmallVec};
use std::ffi::{CStr, CString};
use std::path::Path;
@@ -132,6 +131,60 @@ pub fn time_trace_profiler_finish(file_name: &Path) {
}
}
+pub enum TargetFeatureFoldStrength<'a> {
+ // The feature is only tied when enabling the feature, disabling
+ // this feature shouldn't disable the tied feature.
+ EnableOnly(&'a str),
+ // The feature is tied for both enabling and disabling this feature.
+ Both(&'a str),
+}
+
+impl<'a> TargetFeatureFoldStrength<'a> {
+ fn as_str(&self) -> &'a str {
+ match self {
+ TargetFeatureFoldStrength::EnableOnly(feat) => feat,
+ TargetFeatureFoldStrength::Both(feat) => feat,
+ }
+ }
+}
+
+pub struct LLVMFeature<'a> {
+ pub llvm_feature_name: &'a str,
+ pub dependency: Option<TargetFeatureFoldStrength<'a>>,
+}
+
+impl<'a> LLVMFeature<'a> {
+ pub fn new(llvm_feature_name: &'a str) -> Self {
+ Self { llvm_feature_name, dependency: None }
+ }
+
+ pub fn with_dependency(
+ llvm_feature_name: &'a str,
+ dependency: TargetFeatureFoldStrength<'a>,
+ ) -> Self {
+ Self { llvm_feature_name, dependency: Some(dependency) }
+ }
+
+ pub fn contains(&self, feat: &str) -> bool {
+ self.iter().any(|dep| dep == feat)
+ }
+
+ pub fn iter(&'a self) -> impl Iterator<Item = &'a str> {
+ let dependencies = self.dependency.iter().map(|feat| feat.as_str());
+ std::iter::once(self.llvm_feature_name).chain(dependencies)
+ }
+}
+
+impl<'a> IntoIterator for LLVMFeature<'a> {
+ type Item = &'a str;
+ type IntoIter = impl Iterator<Item = &'a str>;
+
+ fn into_iter(self) -> Self::IntoIter {
+ let dependencies = self.dependency.into_iter().map(|feat| feat.as_str());
+ std::iter::once(self.llvm_feature_name).chain(dependencies)
+ }
+}
+
// WARNING: the features after applying `to_llvm_features` must be known
// to LLVM or the feature detection code will walk past the end of the feature
// array, leading to crashes.
@@ -147,58 +200,65 @@ pub fn time_trace_profiler_finish(file_name: &Path) {
// Though note that Rust can also be build with an external precompiled version of LLVM
// which might lead to failures if the oldest tested / supported LLVM version
// doesn't yet support the relevant intrinsics
-//
-// Note: The first feature in the list that is returned is the mapping to the feature that is
-// provided from the `s` parameter.
-pub fn to_llvm_features<'a>(sess: &Session, s: &'a str) -> SmallVec<[&'a str; 2]> {
+pub fn to_llvm_features<'a>(sess: &Session, s: &'a str) -> LLVMFeature<'a> {
let arch = if sess.target.arch == "x86_64" { "x86" } else { &*sess.target.arch };
match (arch, s) {
- ("x86", "sse4.2") => smallvec!["sse4.2", "crc32"],
- ("x86", "pclmulqdq") => smallvec!["pclmul"],
- ("x86", "rdrand") => smallvec!["rdrnd"],
- ("x86", "bmi1") => smallvec!["bmi"],
- ("x86", "cmpxchg16b") => smallvec!["cx16"],
- ("aarch64", "rcpc2") => smallvec!["rcpc-immo"],
- ("aarch64", "dpb") => smallvec!["ccpp"],
- ("aarch64", "dpb2") => smallvec!["ccdp"],
- ("aarch64", "frintts") => smallvec!["fptoint"],
- ("aarch64", "fcma") => smallvec!["complxnum"],
- ("aarch64", "pmuv3") => smallvec!["perfmon"],
- ("aarch64", "paca") => smallvec!["pauth"],
- ("aarch64", "pacg") => smallvec!["pauth"],
+ ("x86", "sse4.2") => {
+ LLVMFeature::with_dependency("sse4.2", TargetFeatureFoldStrength::EnableOnly("crc32"))
+ }
+ ("x86", "pclmulqdq") => LLVMFeature::new("pclmul"),
+ ("x86", "rdrand") => LLVMFeature::new("rdrnd"),
+ ("x86", "bmi1") => LLVMFeature::new("bmi"),
+ ("x86", "cmpxchg16b") => LLVMFeature::new("cx16"),
+ ("aarch64", "rcpc2") => LLVMFeature::new("rcpc-immo"),
+ ("aarch64", "dpb") => LLVMFeature::new("ccpp"),
+ ("aarch64", "dpb2") => LLVMFeature::new("ccdp"),
+ ("aarch64", "frintts") => LLVMFeature::new("fptoint"),
+ ("aarch64", "fcma") => LLVMFeature::new("complxnum"),
+ ("aarch64", "pmuv3") => LLVMFeature::new("perfmon"),
+ ("aarch64", "paca") => LLVMFeature::new("pauth"),
+ ("aarch64", "pacg") => LLVMFeature::new("pauth"),
// Rust ties fp and neon together.
- ("aarch64", "neon") => smallvec!["neon", "fp-armv8"],
+ ("aarch64", "neon") => {
+ LLVMFeature::with_dependency("neon", TargetFeatureFoldStrength::Both("fp-armv8"))
+ }
// In LLVM neon implicitly enables fp, but we manually enable
// neon when a feature only implicitly enables fp
- ("aarch64", "f32mm") => smallvec!["f32mm", "neon"],
- ("aarch64", "f64mm") => smallvec!["f64mm", "neon"],
- ("aarch64", "fhm") => smallvec!["fp16fml", "neon"],
- ("aarch64", "fp16") => smallvec!["fullfp16", "neon"],
- ("aarch64", "jsconv") => smallvec!["jsconv", "neon"],
- ("aarch64", "sve") => smallvec!["sve", "neon"],
- ("aarch64", "sve2") => smallvec!["sve2", "neon"],
- ("aarch64", "sve2-aes") => smallvec!["sve2-aes", "neon"],
- ("aarch64", "sve2-sm4") => smallvec!["sve2-sm4", "neon"],
- ("aarch64", "sve2-sha3") => smallvec!["sve2-sha3", "neon"],
- ("aarch64", "sve2-bitperm") => smallvec!["sve2-bitperm", "neon"],
- (_, s) => smallvec![s],
- }
-}
-
-pub enum TargetFeatureFoldStrength {
- // The feature is only tied when enabling the feature, disabling
- // this feature shouldn't disable the tied feature.
- EnableOnly,
- // The feature is tied for both enabling and disabling this feature.
- Both,
-}
-
-// Determines how the features are folded together, some features are
-// linked a lot more than some others.
-pub fn feature_fold_strength<'a>(feats: &SmallVec<[&'a str; 2]>) -> TargetFeatureFoldStrength {
- match (feats.get(0), feats.get(1)) {
- (Some(&"neon"), Some(&"fp-armv8")) => TargetFeatureFoldStrength::Both,
- _ => TargetFeatureFoldStrength::EnableOnly,
+ ("aarch64", "f32mm") => {
+ LLVMFeature::with_dependency("f32mm", TargetFeatureFoldStrength::EnableOnly("neon"))
+ }
+ ("aarch64", "f64mm") => {
+ LLVMFeature::with_dependency("f64mm", TargetFeatureFoldStrength::EnableOnly("neon"))
+ }
+ ("aarch64", "fhm") => {
+ LLVMFeature::with_dependency("fp16fml", TargetFeatureFoldStrength::EnableOnly("neon"))
+ }
+ ("aarch64", "fp16") => {
+ LLVMFeature::with_dependency("fullfp16", TargetFeatureFoldStrength::EnableOnly("neon"))
+ }
+ ("aarch64", "jsconv") => {
+ LLVMFeature::with_dependency("jsconv", TargetFeatureFoldStrength::EnableOnly("neon"))
+ }
+ ("aarch64", "sve") => {
+ LLVMFeature::with_dependency("sve", TargetFeatureFoldStrength::EnableOnly("neon"))
+ }
+ ("aarch64", "sve2") => {
+ LLVMFeature::with_dependency("sve2", TargetFeatureFoldStrength::EnableOnly("neon"))
+ }
+ ("aarch64", "sve2-aes") => {
+ LLVMFeature::with_dependency("sve2-aes", TargetFeatureFoldStrength::EnableOnly("neon"))
+ }
+ ("aarch64", "sve2-sm4") => {
+ LLVMFeature::with_dependency("sve2-sm4", TargetFeatureFoldStrength::EnableOnly("neon"))
+ }
+ ("aarch64", "sve2-sha3") => {
+ LLVMFeature::with_dependency("sve2-sha3", TargetFeatureFoldStrength::EnableOnly("neon"))
+ }
+ ("aarch64", "sve2-bitperm") => LLVMFeature::with_dependency(
+ "sve2-bitperm",
+ TargetFeatureFoldStrength::EnableOnly("neon"),
+ ),
+ (_, s) => LLVMFeature::new(s),
}
}
@@ -296,18 +356,17 @@ fn print_target_features(sess: &Session, tm: &llvm::TargetMachine) {
let mut rustc_target_features = supported_target_features(sess)
.iter()
.map(|(feature, _gate)| {
- let desc = if let Some(llvm_feature) = to_llvm_features(sess, *feature).first() {
- // LLVM asserts that these are sorted. LLVM and Rust both use byte comparison for these strings.
+ // LLVM asserts that these are sorted. LLVM and Rust both use byte comparison for these strings.
+ let llvm_feature = to_llvm_features(sess, *feature).llvm_feature_name;
+ let desc =
match llvm_target_features.binary_search_by_key(&llvm_feature, |(f, _d)| f).ok() {
Some(index) => {
known_llvm_target_features.insert(llvm_feature);
llvm_target_features[index].1
}
None => "",
- }
- } else {
- ""
- };
+ };
+
(*feature, desc)
})
.collect::<Vec<_>>();
@@ -491,17 +550,20 @@ pub(crate) fn global_llvm_features(sess: &Session, diagnostics: bool) -> Vec<Str
// passing requests down to LLVM. This means that all in-language
// features also work on the command line instead of having two
// different names when the LLVM name and the Rust name differ.
- let llvm_features = to_llvm_features(sess, feature);
- Some(to_llvm_features(sess, feature).into_iter().enumerate().filter_map(
- move |(idx, f)| match (enable_disable, feature_fold_strength(&llvm_features)) {
- ('-' | '+', TargetFeatureFoldStrength::Both)
- | ('+', TargetFeatureFoldStrength::EnableOnly) => {
- Some(format!("{}{}", enable_disable, f))
- }
- _ if idx == 0 => Some(format!("{}{}", enable_disable, f)),
- _ => None,
- },
- ))
+ let llvm_feature = to_llvm_features(sess, feature);
+
+ Some(
+ std::iter::once(format!("{}{}", enable_disable, llvm_feature.llvm_feature_name))
+ .chain(llvm_feature.dependency.into_iter().filter_map(move |feat| {
+ match (enable_disable, feat) {
+ ('-' | '+', TargetFeatureFoldStrength::Both(f))
+ | ('+', TargetFeatureFoldStrength::EnableOnly(f)) => {
+ Some(format!("{}{}", enable_disable, f))
+ }
+ _ => None,
+ }
+ })),
+ )
})
.flatten();
features.extend(feats);
diff --git a/tests/codegen/tied-features-strength.rs b/tests/codegen/tied-features-strength.rs
index 5dc9ae47e79..51334c12158 100644
--- a/tests/codegen/tied-features-strength.rs
+++ b/tests/codegen/tied-features-strength.rs
@@ -5,19 +5,19 @@
// The "+v8a" feature is matched as optional as it isn't added when we
// are targeting older LLVM versions. Once the min supported version
-// is LLVM-14 we can remove the regex matching for this feature.
+// is LLVM-14 we can remove the optional regex matching for this feature.
// [ENABLE_SVE] compile-flags: -C target-feature=+sve
-// ENABLE_SVE: attributes #0 = { {{.*}} "target-features"="+outline-atomics,+sve,+neon{{(,\+v8a)?}}" }
+// ENABLE_SVE: attributes #0 = { {{.*}} "target-features"="{{((\+outline-atomics,?)|(\+v8a,?)?|(\+sve,?)|(\+neon,?))*}}" }
// [DISABLE_SVE] compile-flags: -C target-feature=-sve
-// DISABLE_SVE: attributes #0 = { {{.*}} "target-features"="+outline-atomics,-sve{{(,\+v8a)?}}" }
+// DISABLE_SVE: attributes #0 = { {{.*}} "target-features"="{{((\+outline-atomics,?)|(\+v8a,?)?|(-sve,?)|(\+neon,?))*}}" }
// [DISABLE_NEON] compile-flags: -C target-feature=-neon
-// DISABLE_NEON: attributes #0 = { {{.*}} "target-features"="+outline-atomics,-neon,-fp-armv8{{(,\+v8a)?}}" }
+// DISABLE_NEON: attributes #0 = { {{.*}} "target-features"="{{((\+outline-atomics,?)|(\+v8a,?)?|(-fp-armv8,?)|(-neon,?))*}}" }
// [ENABLE_NEON] compile-flags: -C target-feature=+neon
-// ENABLE_NEON: attributes #0 = { {{.*}} "target-features"="+outline-atomics,+neon,+fp-armv8{{(,\+v8a)?}}" }
+// ENABLE_NEON: attributes #0 = { {{.*}} "target-features"="{{((\+outline-atomics,?)|(\+v8a,?)?|(\+fp-armv8,?)|(\+neon,?))*}}" }
#![feature(no_core, lang_items)]