[clang] [Clang] feat: Allow AVX/AVX2 permute operations in constexpr (PR #172149)

[Simon Pilgrim via cfe-commits]

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@@ -1439,18 +1439,33 @@ __m256d test_mm256_permute2f128_pd(__m256d A, __m256d B) {
   return _mm256_permute2f128_pd(A, B, 0x31);
 }
 
+TEST_CONSTEXPR(match_m256d(_mm256_permute2f128_pd(((__m256d){1.0, 2.0, 3.0, 4.0}), ((__m256d){5.0, 6.0, 7.0, 8.0}), 0xA7), 7.0, 8.0, 5.0, 6.0));
+TEST_CONSTEXPR(match_m256d(_mm256_permute2f128_pd(((__m256d){1.0, 2.0, 3.0, 4.0}), ((__m256d){5.0, 6.0, 7.0, 8.0}), 0x5F), 7.0, 8.0, 3.0, 4.0));
+TEST_CONSTEXPR(match_m256d(_mm256_permute2f128_pd(((__m256d){1.0, 2.0, 3.0, 4.0}), ((__m256d){5.0, 6.0, 7.0, 8.0}), 0x37), 7.0, 8.0, 7.0, 8.0));
+TEST_CONSTEXPR(match_m256d(_mm256_permute2f128_pd(((__m256d){1.0, 2.0, 3.0, 4.0}), ((__m256d){5.0, 6.0, 7.0, 8.0}), 0x12), 5.0, 6.0, 3.0, 4.0));
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RKSimon wrote:

zeroing mask test coverage?

https://github.com/llvm/llvm-project/pull/172149