[llvm] [IR] Verify parameters of TargetExtTypes (PR #105084)

[Sander de Smalen via llvm-commits]

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@@ -723,6 +724,16 @@ static void forEachUser(const Value *User,
   }
 }
 
+void Verifier::visitTargetExtType(TargetExtType *TTy) {
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sdesmalen-arm wrote:

I would expect that the target-specific types will be almost exclusively used with intrinsics, with the exception of `load`, `store`, `getelementptr` and `alloca`. It's probably worth having these checks for at least these operations.

That said, how bad would it be to verify types in the type cache that are no longer reachable from the Module? These types should never have been created in the first place, so if they were then we could argue the Verifier is merely run too late to point to the exact place they were created, but the error is still valid.

https://github.com/llvm/llvm-project/pull/105084