[llvm] [msan] Convert target("aarch64.svcount") from compile-time crash to MSan false negatives (PR #165028)

[Thurston Dang via llvm-commits]

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@@ -1544,6 +1545,27 @@ struct MemorySanitizerVisitor : public InstVisitor<MemorySanitizerVisitor> {
     }
   }
 
+  static bool isAArch64SVCount(Type *Ty) {
+    if (!isa<TargetExtType>(Ty))
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thurstond wrote:

Replaced

https://github.com/llvm/llvm-project/pull/165028