[clang] [llvm] [AArch64][SME] Remove SelectionDAG SME ABI lowering (PR #190950)

[Sander de Smalen via cfe-commits]

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@@ -50,8 +50,6 @@ SMEAttrs::SMEAttrs(const AttributeList &Attrs) {
     Bitmask |= SM_Body;
   if (Attrs.hasFnAttr("aarch64_za_state_agnostic"))
     Bitmask |= ZA_State_Agnostic;
-  if (Attrs.hasFnAttr("aarch64_zt0_undef"))
-    Bitmask |= ZT0_Undef;
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sdesmalen-arm wrote:

IMO there is little value in keeping the Verifier change if it has no semantic meaning, so I'm happy for that to be removed. I think it should be documented in llvm/docs/AArch64SME.rst as being deprecated (although it wasn't mentioned there before).

https://github.com/llvm/llvm-project/pull/190950