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

[Sander de Smalen via llvm-commits]

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@@ -82,19 +102,86 @@ TEST(SMEAttributes, Basics) {
   // Test PSTATE.ZA interfaces.
   ASSERT_FALSE(SA(SA::ZA_Shared).hasPrivateZAInterface());
   ASSERT_TRUE(SA(SA::ZA_Shared).hasSharedZAInterface());
+  ASSERT_TRUE(SA(SA::ZA_Shared).sharesZA());
   ASSERT_TRUE(SA(SA::ZA_Shared).hasZAState());
   ASSERT_FALSE(SA(SA::ZA_Shared).preservesZA());
   ASSERT_TRUE(SA(SA::ZA_Shared | SA::ZA_Preserved).preservesZA());
 
   ASSERT_TRUE(SA(SA::ZA_New).hasPrivateZAInterface());
+  ASSERT_FALSE(SA(SA::ZA_New).hasSharedZAInterface());
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sdesmalen-arm wrote:

nit: add this case too?
```
ASSERT_FALSE(SA(SA::ZA_Shared).sharesZA());
```

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