Use nearbyint() as alias of rint() for Kokkos SYCL backend

Author: NamjaeChoi

src/utilities/include/metaphysicl/metaphysicl_math.h

@@ -90,6 +90,34 @@ namespace math {
     return detail::unqualified_##NAME(x);                                      \
   }
 
+#ifdef METAPHYSICL_KOKKOS_COMPILATION
+#define METAPHYSICL_MATH_UNARY_ALIAS(ALIAS, NAME)                              \
+  namespace detail {                                                           \
+  template <class X> METAPHYSICL_INLINE auto unqualified_##ALIAS(const X &x) { \
+    if constexpr (std::is_arithmetic_v<X>)                                     \
+      return Kokkos::NAME(x);                                                  \
+    else                                                                       \
+      return NAME(x);                                                          \
+  }                                                                            \
+  }                                                                            \
+  template <class X> METAPHYSICL_INLINE auto ALIAS(const X &x) {               \
+    return detail::unqualified_##ALIAS(x);                                     \
+  }
+#else
+#define METAPHYSICL_MATH_UNARY_ALIAS(ALIAS, NAME)                              \
+  namespace detail {                                                           \
+  template <class X> METAPHYSICL_INLINE auto unqualified_##ALIAS(const X &x) { \
+    if constexpr (std::is_arithmetic_v<X>)                                     \
+      return std::NAME(x);                                                     \
+    else                                                                       \
+      return NAME(x);                                                          \
+  }                                                                            \
+  }                                                                            \
+  template <class X> METAPHYSICL_INLINE auto ALIAS(const X &x) {               \
+    return detail::unqualified_##ALIAS(x);                                     \
+  }
+#endif
+
 // Macro to call when there is a backing math function in c
 #define METAPHYSICL_MATH_BINARY(NAME)                                          \
   METAPHYSICL_MATH_DETAIL_UNQUALIFIED_BINARY(NAME)                             \
@@ -129,7 +157,11 @@ METAPHYSICL_MATH_UNARY(erf)
 METAPHYSICL_MATH_UNARY(erfc)
 METAPHYSICL_MATH_UNARY(trunc)
 METAPHYSICL_MATH_UNARY(round)
+#if defined (METAPHYSICL_KOKKOS_COMPILATION) && defined(KOKKOS_ENABLE_SYCL)
+METAPHYSICL_MATH_UNARY_ALIAS(nearbyint, rint)
+#else
 METAPHYSICL_MATH_UNARY(nearbyint)
+#endif
 METAPHYSICL_MATH_UNARY_STD(rint)
 METAPHYSICL_MATH_UNARY(real)
 METAPHYSICL_MATH_UNARY(imag)