[clang] [Arm] Fix generating code with UB in NeonEmitter (PR #121802)

[Momchil Velikov via cfe-commits]

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@@ -1382,14 +1382,15 @@ void Intrinsic::emitBodyAsBuiltinCall() {
     Type CastToType = T;
 
     // Check if an explicit cast is needed.
-    if (CastToType.isVector() &&
-        (LocalCK == ClassB || (T.isHalf() && !T.isScalarForMangling()))) {
-      CastToType.makeInteger(8, true);
-      Arg = "(" + CastToType.str() + ")" + Arg;
-    } else if (CastToType.isVector() && LocalCK == ClassI) {
-      if (CastToType.isInteger())
-        CastToType.makeSigned();
-      Arg = "(" + CastToType.str() + ")" + Arg;
+    if (CastToType.isVector()) {
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momchil-velikov wrote:

This change is postponed for another time.

https://github.com/llvm/llvm-project/pull/121802