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

[Kerry McLaughlin via llvm-commits]

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@@ -28,6 +31,11 @@ void SMEAttrs::set(unsigned M, bool Enable) {
          "ZA_New and ZA_NoLazySave are mutually exclusive");
   assert(!(hasSharedZAInterface() && (Bitmask & ZA_NoLazySave)) &&
          "ZA_Shared and ZA_NoLazySave are mutually exclusive");
+
+  // ZT0 Attrs
+  assert((!sharesZT0() || (hasNewZT0Body() ^ isZT0In() ^ isZT0InOut() ^
+                           isZT0Out() ^ preservesZT0())) &&
+         "ZT0_New,In,Out,InOut,Preserved are mutually exclusive");
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kmclaughlin-arm wrote:

I've reworded this assert to use the full names, it's now:
`ZT0_New, ZT0_In, ZT0_Out, ZT0_InOut and ZT0_Preserved are all mutually exclusive`

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