[clang] [X86][Clang] Add AVX512 kunpck intrinsics to be used in constexp (PR #167683)

[Simon Pilgrim via cfe-commits]

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@@ -40,6 +40,8 @@ typedef long long __m512i_u __attribute__((__vector_size__(64), __aligned__(1)))
 
 typedef unsigned char __mmask8;
 typedef unsigned short __mmask16;
+typedef unsigned int __mmask32;
+typedef unsigned long long __mmask64;
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RKSimon wrote:

Remove these?

https://github.com/llvm/llvm-project/pull/167683