Only allow upstream calls to LLVM intrinsics, not any link_name function

This commit is contained in:
Ben Kimock 2024-04-01 20:17:12 -04:00
parent 395f780cd8
commit 748dba2baf

View File

@ -14,6 +14,7 @@ use rustc_middle::ty::adjustment::CustomCoerceUnsized;
use rustc_middle::ty::Instance;
use rustc_middle::ty::TyCtxt;
use rustc_middle::ty::{self, Ty};
use rustc_span::def_id::DefId;
use rustc_span::def_id::LOCAL_CRATE;
use rustc_span::ErrorGuaranteed;
@ -57,13 +58,24 @@ fn custom_coerce_unsize_info<'tcx>(
/// linkers will optimize such that dead calls to unresolved symbols are not an error, but this is
/// not guaranteed. So we used this function in codegen backends to ensure we do not generate any
/// unlinkable calls.
///
/// Note that calls to LLVM intrinsics are uniquely okay because they won't make it to the linker.
pub fn is_call_from_compiler_builtins_to_upstream_monomorphization<'tcx>(
tcx: TyCtxt<'tcx>,
instance: Instance<'tcx>,
) -> bool {
!instance.def_id().is_local()
fn is_llvm_intrinsic(tcx: TyCtxt<'_>, def_id: DefId) -> bool {
if let Some(name) = tcx.codegen_fn_attrs(def_id).link_name {
name.as_str().starts_with("llvm.")
} else {
false
}
}
let def_id = instance.def_id();
!def_id.is_local()
&& tcx.is_compiler_builtins(LOCAL_CRATE)
&& tcx.codegen_fn_attrs(instance.def_id()).link_name.is_none()
&& !is_llvm_intrinsic(tcx, def_id)
&& !should_codegen_locally(tcx, instance)
}