[llvm] [AArch64][SME2] Add ZT0 attributes to SMEAttrs (PR #77607)

[Sander de Smalen via llvm-commits]

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@@ -60,6 +69,16 @@ SMEAttrs::SMEAttrs(const AttributeList &Attrs) {
     Bitmask |= ZA_New;
   if (Attrs.hasFnAttr("aarch64_pstate_za_preserved"))
     Bitmask |= ZA_Preserved;
+  if (Attrs.hasFnAttr("aarch64_sme_in_zt0"))
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sdesmalen-arm wrote:

Let's remove the `_sme` part from this, so that it's `aarch64_in_zt0`.

https://github.com/llvm/llvm-project/pull/77607