[clang] [X86][Clang] VectorExprEvaluator::VisitCallExpr / InterpretBuiltin - Allow AVX/AVX512 IFMA madd52 intrinsics to be used in constexpr (PR #161056)

[Simon Pilgrim via cfe-commits]

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@@ -19,52 +19,55 @@
   __attribute__((__always_inline__, __nodebug__, __target__("avx512ifma"),     \
                  __min_vector_width__(512)))
 
-static __inline__ __m512i __DEFAULT_FN_ATTRS
-_mm512_madd52hi_epu64 (__m512i __X, __m512i __Y, __m512i __Z)
-{
-  return (__m512i)__builtin_ia32_vpmadd52huq512((__v8di) __X, (__v8di) __Y,
-                                                (__v8di) __Z);
+#if defined(__cplusplus) && (__cplusplus >= 201103L)
+#define __DEFAULT_FN_ATTRS_CONSTEXPR __DEFAULT_FN_ATTRS constexpr
+#else
+#define __DEFAULT_FN_ATTRS_CONSTEXPR __DEFAULT_FN_ATTRS
+#endif
----------------
RKSimon wrote:

No need for __DEFAULT_FN_ATTRS_CONSTEXPR - all of the functions in this header (and the others) are now constexpr - so we can just define __DEFAULT_FN_ATTRS as constexpr for c++11 or later - see avx512vpopcntdqintrin.h for examples

https://github.com/llvm/llvm-project/pull/161056