[clang] [Clang] Refactor diagnostics for SME builtins. (PR #78258)

[Matthew Devereau via cfe-commits]

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@@ -136,10 +136,10 @@ defm SVWRITE_ZA128 : ZAWrite<"za128", "csilUcUsUiUlhbfd", "aarch64_sme_writeq",
 
 let TargetGuard = "sme" in {
   def SVZERO_MASK_ZA : SInst<"svzero_mask_za", "vi", "", MergeNone, "aarch64_sme_zero",
-                             [IsOverloadNone, IsStreamingCompatible, IsSharedZA],
+                             [IsOverloadNone, IsStreamingCompatible, IsInOutZA],
                              [ImmCheck<0, ImmCheck0_255>]>;
   def SVZERO_ZA      : SInst<"svzero_za", "v", "", MergeNone, "aarch64_sme_zero",
-                             [IsOverloadNone, IsStreamingCompatible, IsSharedZA]>;
+                             [IsOverloadNone, IsStreamingCompatible, IsOutZA]>;
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MDevereau wrote:

I'm a bit confused about this change. `IsOutZA` seems to make sense since the instruction creates a new zeroed ZA state, but doesn't this also mean the old state is input and destroyed?

https://github.com/llvm/llvm-project/pull/78258