Fix Intel oneMKL FFT setup (#4231)

Author: WeiqunZhang

Src/FFT/AMReX_FFT_Helper.H

@@ -254,10 +254,10 @@ struct Plan
         strides.push_back(1);
 #ifndef AMREX_USE_MKL_DFTI_2024
         pp->set_value(oneapi::mkl::dft::config_param::FWD_STRIDES, strides);
-        pp->set_value(oneapi::mkl::dft::config_param::BWD_STRIDES, strides);
+        // Do not set BWD_STRIDES
 #else
         pp->set_value(oneapi::mkl::dft::config_param::FWD_STRIDES, strides.data());
-        pp->set_value(oneapi::mkl::dft::config_param::BWD_STRIDES, strides.data());
+        // Do not set BWD_STRIDES
 #endif
         pp->set_value(oneapi::mkl::dft::config_param::WORKSPACE,
                       oneapi::mkl::dft::config_value::WORKSPACE_EXTERNAL);
@@ -1239,7 +1239,7 @@ void Plan<T>::init_r2c (IntVectND<M> const& fft_size, void* pbf, void* pbb, bool
 
 #ifndef AMREX_USE_MKL_DFTI_2024
     pp->set_value(oneapi::mkl::dft::config_param::FWD_STRIDES, strides);
-    pp->set_value(oneapi::mkl::dft::config_param::BWD_STRIDES, strides);
+    // Do not set BWD_STRIDES
 #else
     pp->set_value(oneapi::mkl::dft::config_param::FWD_STRIDES, strides.data());
     // Do not set BWD_STRIDES

Src/FFT/AMReX_FFT_OpenBCSolver.H

@@ -52,9 +52,6 @@ OpenBCSolver<T>::OpenBCSolver (Box const& domain, Info const& info)
 {
 #if (AMREX_SPACEDIM == 3)
     if (m_info.batch_mode) {
-#if defined(AMREX_USE_SYCL)
-        amrex::Abort("FFT::OpenBCSolver: batch mode not support because Intel does not support batched 2d fft.");
-#endif
         auto gdom = make_grown_domain(domain,m_info);
         gdom.enclosedCells(2);
         gdom.setSmall(2, 0);

Src/FFT/AMReX_FFT_R2C.H

@@ -246,7 +246,7 @@ R2C<T,D,S>::R2C (Box const& domain, Info const& info)
     int myproc = ParallelContext::MyProcSub();
     int nprocs = std::min(ParallelContext::NProcsSub(), m_info.nprocs);
 
-#if (AMREX_SPACEDIM == 3) && !defined(AMREX_USE_SYCL) /* Intel does not support batched 2d fft */
+#if (AMREX_SPACEDIM == 3)
     if (S == DomainStrategy::slab && (m_real_domain.length(1) > 1)) {
         m_slab_decomp = true;
     }