[clang] [CIR][X86] Implement convert_half builtins (PR #171615)

[Priyanshu Kumar via cfe-commits]

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@@ -20,6 +20,7 @@
 #include "clang/Basic/TargetBuiltins.h"
 #include "clang/CIR/Dialect/IR/CIRTypes.h"
 #include "clang/CIR/MissingFeatures.h"
+#include "llvm/Support/Casting.h"
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Priyanshu3820 wrote:

yes, since we're using mlir::cast, it is indeed not needed. Will remove it

https://github.com/llvm/llvm-project/pull/171615