Rollup merge of #142854 - folkertdev:centralize-min-function-alignment, r=workingjubilee

centralize `-Zmin-function-alignment` logic

tracking issue: https://github.com/rust-lang/rust/issues/82232
discussed in: https://github.com/rust-lang/rust/pull/142824#discussion_r2160056244

Apply the `-Zmin-function-alignment` value to the alignment field of the function attributes when those are created, so that individual backends don't need to consider it.

The one exception right now is cranelift, because it can't yet set the alignment for individual functions, but it can (and does) set the global minimum function alignment.

cc ``@RalfJung`` I think this is an improvement regardless, is there anything else that should be done for miri?

1 files changed, 1 insertions, 5 deletions

diff --git a/compiler/rustc_codegen_llvm/src/attributes.rs b/compiler/rustc_codegen_llvm/src/attributes.rs
index 27fd09745ff..adb53e0b66c 100644
--- a/compiler/rustc_codegen_llvm/src/attributes.rs
+++ b/compiler/rustc_codegen_llvm/src/attributes.rs
@@ -491,11 +491,7 @@ pub(crate) fn llfn_attrs_from_instance<'ll, 'tcx>(
         let allocated_pointer = AttributeKind::AllocatedPointer.create_attr(cx.llcx);
         attributes::apply_to_llfn(llfn, AttributePlace::Argument(0), &[allocated_pointer]);
     }
-    // function alignment can be set globally with the `-Zmin-function-alignment=<n>` flag;
-    // the alignment from a `#[repr(align(<n>))]` is used if it specifies a higher alignment.
-    if let Some(align) =
-        Ord::max(cx.tcx.sess.opts.unstable_opts.min_function_alignment, codegen_fn_attrs.alignment)
-    {
+    if let Some(align) = codegen_fn_attrs.alignment {
         llvm::set_alignment(llfn, align);
     }
     if let Some(backchain) = backchain_attr(cx) {