Move llvm_target_features back to llvm_util

Author: bjorn3

src/librustc_codegen_llvm/llvm_util.rs

@@ -20,8 +20,6 @@ use syntax::feature_gate::UnstableFeatures;
 use std::sync::atomic::{AtomicBool, Ordering};
 use std::sync::Once;
 
-pub use rustc_codegen_utils::llvm_target_features::*;
-
 static POISONED: AtomicBool = AtomicBool::new(false);
 static INIT: Once = Once::new();
 
@@ -81,6 +79,108 @@ unsafe fn configure_llvm(sess: &Session) {
                                  llvm_args.as_ptr());
 }
 
+// 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.
+
+const ARM_WHITELIST: &[(&str, Option<&str>)] = &[
+    ("mclass", Some("arm_target_feature")),
+    ("neon", Some("arm_target_feature")),
+    ("v7", Some("arm_target_feature")),
+    ("vfp2", Some("arm_target_feature")),
+    ("vfp3", Some("arm_target_feature")),
+    ("vfp4", Some("arm_target_feature")),
+];
+
+const AARCH64_WHITELIST: &[(&str, Option<&str>)] = &[
+    ("fp", Some("aarch64_target_feature")),
+    ("neon", Some("aarch64_target_feature")),
+    ("sve", Some("aarch64_target_feature")),
+    ("crc", Some("aarch64_target_feature")),
+    ("crypto", Some("aarch64_target_feature")),
+    ("ras", Some("aarch64_target_feature")),
+    ("lse", Some("aarch64_target_feature")),
+    ("rdm", Some("aarch64_target_feature")),
+    ("fp16", Some("aarch64_target_feature")),
+    ("rcpc", Some("aarch64_target_feature")),
+    ("dotprod", Some("aarch64_target_feature")),
+    ("v8.1a", Some("aarch64_target_feature")),
+    ("v8.2a", Some("aarch64_target_feature")),
+    ("v8.3a", Some("aarch64_target_feature")),
+];
+
+const X86_WHITELIST: &[(&str, Option<&str>)] = &[
+    ("aes", None),
+    ("avx", None),
+    ("avx2", None),
+    ("avx512bw", Some("avx512_target_feature")),
+    ("avx512cd", Some("avx512_target_feature")),
+    ("avx512dq", Some("avx512_target_feature")),
+    ("avx512er", Some("avx512_target_feature")),
+    ("avx512f", Some("avx512_target_feature")),
+    ("avx512ifma", Some("avx512_target_feature")),
+    ("avx512pf", Some("avx512_target_feature")),
+    ("avx512vbmi", Some("avx512_target_feature")),
+    ("avx512vl", Some("avx512_target_feature")),
+    ("avx512vpopcntdq", Some("avx512_target_feature")),
+    ("bmi1", None),
+    ("bmi2", None),
+    ("fma", None),
+    ("fxsr", None),
+    ("lzcnt", None),
+    ("mmx", Some("mmx_target_feature")),
+    ("pclmulqdq", None),
+    ("popcnt", None),
+    ("rdrand", None),
+    ("rdseed", None),
+    ("sha", None),
+    ("sse", None),
+    ("sse2", None),
+    ("sse3", None),
+    ("sse4.1", None),
+    ("sse4.2", None),
+    ("sse4a", Some("sse4a_target_feature")),
+    ("ssse3", None),
+    ("tbm", Some("tbm_target_feature")),
+    ("xsave", None),
+    ("xsavec", None),
+    ("xsaveopt", None),
+    ("xsaves", None),
+];
+
+const HEXAGON_WHITELIST: &[(&str, Option<&str>)] = &[
+    ("hvx", Some("hexagon_target_feature")),
+    ("hvx-double", Some("hexagon_target_feature")),
+];
+
+const POWERPC_WHITELIST: &[(&str, Option<&str>)] = &[
+    ("altivec", Some("powerpc_target_feature")),
+    ("power8-altivec", Some("powerpc_target_feature")),
+    ("power9-altivec", Some("powerpc_target_feature")),
+    ("power8-vector", Some("powerpc_target_feature")),
+    ("power9-vector", Some("powerpc_target_feature")),
+    ("vsx", Some("powerpc_target_feature")),
+];
+
+const MIPS_WHITELIST: &[(&str, Option<&str>)] = &[
+    ("fp64", Some("mips_target_feature")),
+    ("msa", Some("mips_target_feature")),
+];
+
+/// When rustdoc is running, provide a list of all known features so that all their respective
+/// primtives may be documented.
+///
+/// IMPORTANT: If you're adding another whitelist to the above lists, make sure to add it to this
+/// iterator!
+pub fn all_known_features() -> impl Iterator<Item=(&'static str, Option<&'static str>)> {
+    ARM_WHITELIST.iter().cloned()
+        .chain(AARCH64_WHITELIST.iter().cloned())
+        .chain(X86_WHITELIST.iter().cloned())
+        .chain(HEXAGON_WHITELIST.iter().cloned())
+        .chain(POWERPC_WHITELIST.iter().cloned())
+        .chain(MIPS_WHITELIST.iter().cloned())
+}
+
 pub fn to_llvm_feature<'a>(sess: &Session, s: &'a str) -> &'a str {
     let arch = if sess.target.target.arch == "x86_64" {
         "x86"
@@ -116,6 +216,20 @@ pub fn target_features(sess: &Session) -> Vec<Symbol> {
         .map(|feature| Symbol::intern(feature)).collect()
 }
 
+pub fn target_feature_whitelist(sess: &Session)
+    -> &'static [(&'static str, Option<&'static str>)]
+{
+    match &*sess.target.target.arch {
+        "arm" => ARM_WHITELIST,
+        "aarch64" => AARCH64_WHITELIST,
+        "x86" | "x86_64" => X86_WHITELIST,
+        "hexagon" => HEXAGON_WHITELIST,
+        "mips" | "mips64" => MIPS_WHITELIST,
+        "powerpc" | "powerpc64" => POWERPC_WHITELIST,
+        _ => &[],
+    }
+}
+
 pub fn print_version() {
     // Can be called without initializing LLVM
     unsafe {

src/librustc_codegen_utils/codegen_backend.rs

@@ -42,6 +42,7 @@ use rustc::middle::cstore::EncodedMetadata;
 use rustc::middle::cstore::MetadataLoader;
 use rustc::dep_graph::DepGraph;
 use rustc_target::spec::Target;
+use rustc_data_structures::fx::FxHashMap;
 use rustc_mir::monomorphize::collector;
 use link::{build_link_meta, out_filename};
 
@@ -132,9 +133,7 @@ impl CodegenBackend for MetadataOnlyCodegenBackend {
         ::symbol_names::provide(providers);
 
         providers.target_features_whitelist = |_tcx, _cnum| {
-            Lrc::new(::llvm_target_features::all_known_features()
-                .map(|(a, b)| (a.to_string(), b.map(|s| s.to_string())))
-                .collect())
+            Lrc::new(FxHashMap()) // Just a dummy
         };
         providers.is_reachable_non_generic = |_tcx, _defid| true;
         providers.exported_symbols = |_tcx, _crate| Arc::new(Vec::new());

src/librustc_codegen_utils/lib.rs

@@ -44,7 +44,6 @@ pub mod link;
 pub mod codegen_backend;
 pub mod symbol_names;
 pub mod symbol_names_test;
-pub mod llvm_target_features;
 
 /// check for the #[rustc_error] annotation, which forces an
 /// error in codegen. This is used to write compile-fail tests