Don't set TORCH_CUDA_ARCH_LIST by default

CMakeLists.txt

@@ -81,6 +81,12 @@ if(GPU_RUNTIME STREQUAL "CUDA")
         if(NOT OPENSPLAT_MAX_CUDA_COMPATIBILITY)
             if(NOT CMAKE_CUDA_ARCHITECTURES)
                 SET(CMAKE_CUDA_ARCHITECTURES 70;75;80)
+            elseif (NOT TORCH_CUDA_ARCH_LIST)
+                # Set torch cuda architecture list
+                set(TORCH_CUDA_ARCH_LIST ${CMAKE_CUDA_ARCHITECTURES})
+                list(TRANSFORM TORCH_CUDA_ARCH_LIST REPLACE "([0-9])([0-9])" "\\1.\\2")
+                string(REPLACE ";" " " TORCH_CUDA_ARCH_LIST "${TORCH_CUDA_ARCH_LIST}")
+                message(STATUS "** Updated TORCH_CUDA_ARCH_LIST to ${TORCH_CUDA_ARCH_LIST} **")
             endif()
         else()
             # Build for maximum compatibility
@@ -110,11 +116,6 @@ if(GPU_RUNTIME STREQUAL "CUDA")
             endforeach()
             message("Set CUDA flags: " ${CMAKE_CUDA_FLAGS})
         endif()
-        # Set torch cuda architecture list
-        set(TORCH_CUDA_ARCH_LIST ${CMAKE_CUDA_ARCHITECTURES})
-        list(TRANSFORM TORCH_CUDA_ARCH_LIST REPLACE "([0-9])([0-9])" "\\1.\\2")
-        string(REPLACE ";" " " TORCH_CUDA_ARCH_LIST "${TORCH_CUDA_ARCH_LIST}")
-        message(STATUS "** Updated TORCH_CUDA_ARCH_LIST to ${TORCH_CUDA_ARCH_LIST} **")
     endif()
 elseif(GPU_RUNTIME STREQUAL "HIP")
     set(USE_HIP ON CACHE BOOL "Use HIP for GPU acceleration")