[llvm] [AArch64][SME2] Preserve ZT0 state around function calls (PR #76968)

[Sander de Smalen via llvm-commits]

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@@ -82,6 +93,13 @@ class SMEAttrs {
   bool hasZAState() const {
     return hasNewZABody() || hasSharedZAInterface();
   }
+
+  // Interfaces to query ZT0 state
+  bool hasNewZTBody() const { return Bitmask & ZT_New; }
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sdesmalen-arm wrote:

Just pointing out that all these interfaces are missing `0` in `ZT0`.

https://github.com/llvm/llvm-project/pull/76968