Fix issue with callsite inline attribute not being applied sometimes.

compiler/rustc_codegen_llvm/src/builder.rs

@@ -17,7 +17,7 @@ use rustc_codegen_ssa::traits::*;
 use rustc_data_structures::small_c_str::SmallCStr;
 use rustc_hir::def_id::DefId;
 use rustc_middle::bug;
-use rustc_middle::middle::codegen_fn_attrs::CodegenFnAttrs;
+use rustc_middle::middle::codegen_fn_attrs::{CodegenFnAttrs, TargetFeature, TargetFeatureKind};
 use rustc_middle::ty::layout::{
  FnAbiError, FnAbiOfHelpers, FnAbiRequest, HasTypingEnv, LayoutError, LayoutOfHelpers,
  TyAndLayout,
@@ -1419,14 +1419,18 @@ impl<'a, 'll, 'tcx> BuilderMethods<'a, 'tcx> for Builder<'a, 'll, 'tcx> {
  // Attributes on the function definition being called
  let fn_defn_attrs = self.cx.tcx.codegen_fn_attrs(instance.def_id());
  if let Some(fn_call_attrs) = fn_call_attrs
- && !fn_call_attrs.target_features.is_empty()
  // If there is an inline attribute and a target feature that matches
  // we will add the attribute to the callsite otherwise we'll omit
  // this and not add the attribute to prevent soundness issues.
  && let Some(inlining_rule) = attributes::inline_attr(&self.cx, self.cx.tcx, instance)
  && self.cx.tcx.is_target_feature_call_safe(
- &fn_call_attrs.target_features,
  &fn_defn_attrs.target_features,
+ &fn_call_attrs.target_features.iter().cloned().chain(
+ self.cx.tcx.sess.target_features.iter().map(|feat| TargetFeature {
+ name: *feat,
+ kind: TargetFeatureKind::Implied,
+ })
+ ).collect::<Vec<_>>(),
  )
  {
  attributes::apply_to_callsite(

compiler/rustc_middle/src/ty/context.rs

@@ -2088,6 +2088,8 @@ impl<'tcx> TyCtxt<'tcx> {
  self.sess.dcx()
  }
 
+ /// Checks to see if the caller (`body_features`) has all the features required by the callee
+ /// (`callee_features`).
  pub fn is_target_feature_call_safe(
  self,
  callee_features: &[TargetFeature],

tests/codegen-llvm/inline-always-callsite.rs

@@ -0,0 +1,41 @@
+//@ add-core-stubs
+//@ compile-flags: --target aarch64-unknown-linux-gnu -Zinline-mir=no -C no-prepopulate-passes
+//@ needs-llvm-components: aarch64
+
+#![crate_type = "lib"]
+#![feature(no_core, lang_items, target_feature_inline_always)]
+#![no_core]
+
+extern crate minicore;
+use minicore::*;
+
+#[inline(always)]
+#[target_feature(enable = "neon")]
+#[no_mangle]
+pub fn single_target_feature() -> i32 {
+ 42
+}
+
+#[inline(always)]
+#[target_feature(enable = "neon,i8mm")]
+#[no_mangle]
+// CHECK: define noundef i32 @multiple_target_features() unnamed_addr #1 {
+pub fn multiple_target_features() -> i32 {
+ // CHECK: %_0 = call noundef i32 @single_target_feature() #3
+ single_target_feature()
+}
+
+#[no_mangle]
+// CHECK: define noundef i32 @inherits_from_global() unnamed_addr #2 {
+pub fn inherits_from_global() -> i32 {
+ unsafe {
+ // CHECK: %_0 = call noundef i32 @single_target_feature() #3
+ single_target_feature()
+ }
+}
+
+// Attribute #3 requires the alwaysinline attribute, the alwaysinline attribute is not emitted on a
+// function definition when target features are present, rather it will be moved onto the function
+// call, if the features match up.
+//
+// CHECK: attributes #3 = { alwaysinline nounwind }