[clang] [Clang] Add constexpr support for AVX512 permutex2 intrinsics (PR #165085)

[NagaChaitanya Vellanki via cfe-commits]

================
@@ -3316,13 +3316,13 @@ _mm512_mask_blend_ph(__mmask32 __U, __m512h __A, __m512h __W) {
                                               (__v32hf)__A);
 }
 
-static __inline__ __m512h __DEFAULT_FN_ATTRS512
+static __inline__ __m512h __DEFAULT_FN_ATTRS512_CONSTEXPR
 _mm512_permutex2var_ph(__m512h __A, __m512i __I, __m512h __B) {
   return (__m512h)__builtin_ia32_vpermi2varhi512((__v32hi)__A, (__v32hi)__I,
                                                  (__v32hi)__B);
 }
 
-static __inline__ __m512h __DEFAULT_FN_ATTRS512
+static __inline__ __m512h __DEFAULT_FN_ATTRS512_CONSTEXPR
----------------
chaitanyav wrote:

@RKSimon sure, will look into this.

https://github.com/llvm/llvm-project/pull/165085