Add ufunc implementation

Author: antonwolfy

dpnp/backend/extensions/ufunc/elementwise_functions/erf_funcs.cpp

@@ -209,6 +209,7 @@ static void populate(py::module_ m,
 
 MACRO_DEFINE_IMPL(erf, Erf);
 MACRO_DEFINE_IMPL(erfc, Erfc);
+MACRO_DEFINE_IMPL(erfcx, Erfcx);
 } // namespace impl
 
 void init_erf_funcs(py::module_ m)
@@ -228,5 +229,9 @@ void init_erf_funcs(py::module_ m)
     impl::populate<impl::ErfcContigFactory, impl::ErfcStridedFactory>(
         m, "_erfc", "", impl::erfc_contig_dispatch_vector,
         impl::erfc_strided_dispatch_vector);
+
+    impl::populate<impl::ErfcxContigFactory, impl::ErfcxStridedFactory>(
+        m, "_erfcx", "", impl::erfcx_contig_dispatch_vector,
+        impl::erfcx_strided_dispatch_vector);
 }
 } // namespace dpnp::extensions::ufunc

dpnp/backend/kernels/elementwise_functions/erf.hpp

@@ -29,6 +29,19 @@
 
 #include <sycl/sycl.hpp>
 
+/**
+ * Include <sycl/ext/intel/math.hpp> only when targeting to Intel devices.
+ */
+#if defined(__INTEL_LLVM_COMPILER)
+#define __SYCL_EXT_INTEL_MATH_SUPPORT
+#endif
+
+#if defined(__SYCL_EXT_INTEL_MATH_SUPPORT)
+#include <sycl/ext/intel/math.hpp>
+#else
+#include <cmath>
+#endif
+
 namespace dpnp::kernels::erfs
 {
 template <typename OpT, typename ArgT, typename ResT>
@@ -62,13 +75,20 @@ struct BaseFunctor
         template <typename Tp>                                                 \
         static Tp apply(const Tp &x)                                           \
         {                                                                      \
-            return sycl::__name__(x);                                          \
+            return __name__(x);                                                \
         }                                                                      \
     };                                                                         \
                                                                                \
     template <typename ArgT, typename ResT>                                    \
     using __f_name__##Functor = BaseFunctor<__f_name__##Op, ArgT, ResT>;
 
-MACRO_DEFINE_FUNCTOR(erf, Erf);
-MACRO_DEFINE_FUNCTOR(erfc, Erfc);
+MACRO_DEFINE_FUNCTOR(sycl::erf, Erf);
+MACRO_DEFINE_FUNCTOR(sycl::erfc, Erfc);
+MACRO_DEFINE_FUNCTOR(
+#if defined(__SYCL_EXT_INTEL_MATH_SUPPORT)
+    sycl::ext::intel::math::erfcx,
+#else
+    std::erfc,
+#endif
+    Erfcx);
 } // namespace dpnp::kernels::erfs