Another try to correctly implement the rust simd flag settings

CMakeLists.txt

@@ -26,17 +26,28 @@ include_directories(lib/gemmi)
 
 add_subdirectory(lib/corrosion)
 
-if (X64 OR X86)
-    if (HAVE_AVX2_EXTENSIONS)
-        set(RUST_FEATURE simd_avx2)
-    elseif (HAVE_SSE2_EXTENSIONS)
-        set(RUST_FEATURE simd_sse2)
-    else()
-        message(FATAL_ERROR "No SIMD support for this architecture")
-    endif()
-elseif (ARM)
+set(RUST_FEATURE "")
+if(HAVE_AVX2)
+    set(RUST_FEATURE simd_avx2)
+elseif(HAVE_SSE4_1 OR HAVE_SSE2)
+    set(RUST_FEATURE simd_sse2)
+elseif(HAVE_ARM8)
     set(RUST_FEATURE simd_neon)
-else()
+endif()
+
+if (NATIVE_ARCH AND (RUST_FEATURE STREQUAL ""))
+    if(ARM)
+        set(RUST_FEATURE simd_neon)
+    elseif(X86 OR X64)
+        if (HAVE_AVX2_EXTENSIONS)
+            set(RUST_FEATURE simd_avx2)
+        elseif (HAVE_SSE2_EXTENSIONS)
+            set(RUST_FEATURE simd_sse2)
+        endif()
+    endif()
+endif()
+
+if(RUST_FEATURE STREQUAL "")
     message(FATAL_ERROR "No SIMD support for this architecture")
 endif()
 message("-- Rust Feature: ${RUST_FEATURE}")