[clang] [Headers][X86] Allow AVX512 masked shuffles to be used in constexpr (PR #162301)

[Simon Pilgrim via cfe-commits]

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@@ -12,6 +12,22 @@
 #include <immintrin.h>
 #include "builtin_test_helpers.h"
 
+// constexpr coverage for i32x8/f32x8 broadcasts (DQ)
+
+  
+  TEST_CONSTEXPR(match_v16si(_mm512_mask_broadcast_i32x8(_mm512_setzero_si512(), 0xFFFF, _mm256_set1_epi32(8)),
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RKSimon wrote:

(style) Please move these next to the corresponding test_* function - we want all test coverage for _mm512_mask_broadcast_i32x8 etc. to be close together

https://github.com/llvm/llvm-project/pull/162301