1 files changed, 20 insertions, 13 deletions

diff --git a/compiler/rustc_codegen_llvm/src/attributes.rs b/compiler/rustc_codegen_llvm/src/attributes.rs
index fde95104093..92a857c2adc 100644
--- a/compiler/rustc_codegen_llvm/src/attributes.rs
+++ b/compiler/rustc_codegen_llvm/src/attributes.rs
@@ -1,6 +1,6 @@
 //! Set and unset common attributes on LLVM values.
 
-pub use rustc_attr::{InlineAttr, InstructionSetAttr, OptimizeAttr};
+use rustc_attr::{InlineAttr, InstructionSetAttr, OptimizeAttr};
 use rustc_codegen_ssa::traits::*;
 use rustc_hir::def_id::DefId;
 use rustc_middle::middle::codegen_fn_attrs::{CodegenFnAttrFlags, PatchableFunctionEntry};
@@ -17,13 +17,13 @@ use crate::llvm::{self, AllocKindFlags, Attribute, AttributeKind, AttributePlace
 use crate::value::Value;
 use crate::{attributes, llvm_util};
 
-pub fn apply_to_llfn(llfn: &Value, idx: AttributePlace, attrs: &[&Attribute]) {
+pub(crate) fn apply_to_llfn(llfn: &Value, idx: AttributePlace, attrs: &[&Attribute]) {
     if !attrs.is_empty() {
         llvm::AddFunctionAttributes(llfn, idx, attrs);
     }
 }
 
-pub fn apply_to_callsite(callsite: &Value, idx: AttributePlace, attrs: &[&Attribute]) {
+pub(crate) fn apply_to_callsite(callsite: &Value, idx: AttributePlace, attrs: &[&Attribute]) {
     if !attrs.is_empty() {
         llvm::AddCallSiteAttributes(callsite, idx, attrs);
     }
@@ -80,7 +80,7 @@ fn patchable_function_entry_attrs<'ll>(
 
 /// Get LLVM sanitize attributes.
 #[inline]
-pub fn sanitize_attrs<'ll>(
+pub(crate) fn sanitize_attrs<'ll>(
     cx: &CodegenCx<'ll, '_>,
     no_sanitize: SanitizerSet,
 ) -> SmallVec<[&'ll Attribute; 4]> {
@@ -120,7 +120,7 @@ pub fn sanitize_attrs<'ll>(
 
 /// Tell LLVM to emit or not emit the information necessary to unwind the stack for the function.
 #[inline]
-pub fn uwtable_attr(llcx: &llvm::Context, use_sync_unwind: Option<bool>) -> &Attribute {
+pub(crate) fn uwtable_attr(llcx: &llvm::Context, use_sync_unwind: Option<bool>) -> &Attribute {
     // NOTE: We should determine if we even need async unwind tables, as they
     // take have more overhead and if we can use sync unwind tables we
     // probably should.
@@ -128,7 +128,7 @@ pub fn uwtable_attr(llcx: &llvm::Context, use_sync_unwind: Option<bool>) -> &Att
     llvm::CreateUWTableAttr(llcx, async_unwind)
 }
 
-pub fn frame_pointer_type_attr<'ll>(cx: &CodegenCx<'ll, '_>) -> Option<&'ll Attribute> {
+pub(crate) fn frame_pointer_type_attr<'ll>(cx: &CodegenCx<'ll, '_>) -> Option<&'ll Attribute> {
     let mut fp = cx.sess().target.frame_pointer;
     let opts = &cx.sess().opts;
     // "mcount" function relies on stack pointer.
@@ -280,19 +280,19 @@ fn backchain_attr<'ll>(cx: &CodegenCx<'ll, '_>) -> Option<&'ll Attribute> {
     if found_positive { Some(llvm::CreateAttrString(cx.llcx, "backchain")) } else { None }
 }
 
-pub fn target_cpu_attr<'ll>(cx: &CodegenCx<'ll, '_>) -> &'ll Attribute {
+pub(crate) fn target_cpu_attr<'ll>(cx: &CodegenCx<'ll, '_>) -> &'ll Attribute {
     let target_cpu = llvm_util::target_cpu(cx.tcx.sess);
     llvm::CreateAttrStringValue(cx.llcx, "target-cpu", target_cpu)
 }
 
-pub fn tune_cpu_attr<'ll>(cx: &CodegenCx<'ll, '_>) -> Option<&'ll Attribute> {
+pub(crate) fn tune_cpu_attr<'ll>(cx: &CodegenCx<'ll, '_>) -> Option<&'ll Attribute> {
     llvm_util::tune_cpu(cx.tcx.sess)
         .map(|tune_cpu| llvm::CreateAttrStringValue(cx.llcx, "tune-cpu", tune_cpu))
 }
 
 /// Get the `NonLazyBind` LLVM attribute,
 /// if the codegen options allow skipping the PLT.
-pub fn non_lazy_bind_attr<'ll>(cx: &CodegenCx<'ll, '_>) -> Option<&'ll Attribute> {
+pub(crate) fn non_lazy_bind_attr<'ll>(cx: &CodegenCx<'ll, '_>) -> Option<&'ll Attribute> {
     // Don't generate calls through PLT if it's not necessary
     if !cx.sess().needs_plt() {
         Some(AttributeKind::NonLazyBind.create_attr(cx.llcx))
@@ -327,7 +327,7 @@ fn create_alloc_family_attr(llcx: &llvm::Context) -> &llvm::Attribute {
 /// Helper for `FnAbi::apply_attrs_llfn`:
 /// Composite function which sets LLVM attributes for function depending on its AST (`#[attribute]`)
 /// attributes.
-pub fn llfn_attrs_from_instance<'ll, 'tcx>(
+pub(crate) fn llfn_attrs_from_instance<'ll, 'tcx>(
     cx: &CodegenCx<'ll, 'tcx>,
     llfn: &'ll Value,
     instance: ty::Instance<'tcx>,
@@ -521,13 +521,20 @@ pub fn llfn_attrs_from_instance<'ll, 'tcx>(
 
     let function_features = function_features
         .iter()
-        .flat_map(|feat| {
-            llvm_util::to_llvm_features(cx.tcx.sess, feat).into_iter().map(|f| format!("+{f}"))
-        })
+        // Convert to LLVMFeatures and filter out unavailable ones
+        .flat_map(|feat| llvm_util::to_llvm_features(cx.tcx.sess, feat))
+        // Convert LLVMFeatures & dependencies to +<feats>s
+        .flat_map(|feat| feat.into_iter().map(|f| format!("+{f}")))
         .chain(codegen_fn_attrs.instruction_set.iter().map(|x| match x {
             InstructionSetAttr::ArmA32 => "-thumb-mode".to_string(),
             InstructionSetAttr::ArmT32 => "+thumb-mode".to_string(),
         }))
+        // HACK: LLVM versions 19+ do not have the FPMR feature and treat it as always enabled
+        // It only exists as a feature in LLVM 18, cannot be passed down for any other version
+        .chain(match &*cx.tcx.sess.target.arch {
+            "aarch64" if llvm_util::get_version().0 == 18 => vec!["+fpmr".to_string()],
+            _ => vec![],
+        })
         .collect::<Vec<String>>();
 
     if cx.tcx.sess.target.is_like_wasm {