[clang] [X86][Clang] Add AVX512 Integer Comparison Intrinsics for constexpr Evaluation (PR #164026)

[Simon Pilgrim via cfe-commits]

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@@ -645,6 +645,21 @@ __mmask16 test_mm_cmp_epi8_mask(__m128i __a, __m128i __b) {
   return (__mmask16)_mm_cmp_epi8_mask(__a, __b, 0);
 }
 
+TEST_CONSTEXPR(_mm_cmpeq_epi8_mask(
+  ((__m128i)(__v16qi){5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5}),
+  ((__m128i)(__v16qi){3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3})
+) == (__mmask16)0x0000);
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RKSimon wrote:

(style) avoid splat vector values in tests

https://github.com/llvm/llvm-project/pull/164026