[clang] [Headers][X86] Allow AVX512 _mm512_set* intrinsics to be used in constexpr (PR #152910)

[Simon Pilgrim via cfe-commits]

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@@ -13,12 +14,14 @@ __m128h test_mm_setzero_ph(void) {
   // CHECK: zeroinitializer
   return _mm_setzero_ph();
 }
+TEST_CONSTEXPR(match_m128(_mm_setzero_ph(), +0.0f, +0.0f, +0.0f, +0.0f, +0.0f, +0.0f, +0.0f, +0.0f));
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RKSimon wrote:

I suspect you're going to have to add match_m128h/match_m256/match_m512h helpers to correctly match float16 entries

https://github.com/llvm/llvm-project/pull/152910