[clang] [HLSL] Add support for elementwise and aggregate splat casting struct types with bitfields (PR #161263)

[Helena Kotas via cfe-commits]

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@@ -85,3 +85,41 @@ export void call5() {
   int1 A = {1};
   S s = (S)A;
 }
+
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hekota wrote:

`call3` and `call5` seems to be identical test cases.

https://github.com/llvm/llvm-project/pull/161263