[clang] [llvm] [TargetParser][AArch64] Add alias for FEAT_RDM. (PR #80540)

[Alexandros Lamprineas via cfe-commits]

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@@ -673,7 +673,7 @@ int hoo(void) {
 //
 //
 // CHECK: Function Attrs: noinline nounwind optnone
-// CHECK-LABEL: define {{[^@]+}}@fmv_inline._MlseMrdm
+// CHECK-LABEL: define {{[^@]+}}@fmv_inline._MlseMrdma
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labrinea wrote:

I raised this with the GCC team, I don't have an answer yet but I believe GCC only accepts "rdma" on the attribute (so I suppose that makes its way to the mangled name?). I remember you raised this matter again in a previous review, when we changed priorities and the mangling was affected. That is a good point but I think first we need to agree whether those functions are part of the ABI or not. Right now I don't see why they need to be. We could even make then have internal linkage, no? If I am mistaken a counter example would help, thanks!

https://github.com/llvm/llvm-project/pull/80540