[llvm] [IR] Check parameters of target extension types on construction (PR #107268)

[Brandon Wu via llvm-commits]

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@@ -3530,7 +3530,12 @@ bool LLParser::parseTargetExtType(Type *&Result) {
   if (parseToken(lltok::rparen, "expected ')' in target extension type"))
     return true;
 
-  Result = TargetExtType::get(Context, TypeName, TypeParams, IntParams);
+  auto TTy =
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4vtomat wrote:

Can we just use `targetexttype::get` here and just make `cantFail` check the error instead of checking here?

https://github.com/llvm/llvm-project/pull/107268