Enable compilation with CUDA (when we generate the library)

CMakeLists.txt

@@ -289,8 +289,28 @@ if( ScalFMM_USE_STARPU )
     
     MESSAGE(STATUS "         STARPU_LIBRARIES          = ${STARPU_LIBRARIES}")
     MESSAGE(STATUS "         STARPU_INCLUDES           = ${STARPU_INCLUDES}")
+    
+  OPTION( ScalFMM_USE_CUDA      "Set to ON to use CUDA with StarPU" OFF )
+  if(ScalFMM_USE_CUDA)
+        execute_process(COMMAND nvcc --version ERROR_VARIABLE cuda_error_output OUTPUT_QUIET)
+        if(cuda_error_output)
+            message( FATAL_ERROR "nvcc is needed with CUDA." )
+        endif()
+        if(NOT DEFINED CUSTOM_CUDA_FLAGS)
+            SET( CUSTOM_CUDA_FLAGS "-std=c++11;-arch=sm_20" CACHE STRING "Set your CUDA flags, for example : -arch=sm_20;-ptxas-options=-v;-use_fast_math")
+        endif()
+        # This is needed to remove backslash after space in ADD_CUSTOM_COMMAND
+        SEPARATE_ARGUMENTS(CUSTOM_CUDA_FLAGS)
+        MESSAGE( STATUS "CUSTOM_CUDA_FLAGS             = ${CUSTOM_CUDA_FLAGS}" )
+     
+        # Add libcudart and cuda.h
+        # link_directories($ENV{CUDA_LIB})
+        include_directories(${$ENV{CUDA_INC}})
+        SET(SCALFMM_LIBRARIES "${SCALFMM_LIBRARIES}; -L$ENV{CUDA_LIB}; -lcudart")
+  endif()
 endif(ScalFMM_USE_STARPU)
 list(APPEND FUSE_LIST "STARPU")
+list(APPEND FUSE_LIST "CUDA")
 #
 ##################################################################
 #                                               Use SSE                                                                     #

Src/CMakeLists.txt

@@ -17,11 +17,35 @@ file(
 	./*.cpp
 )
 
+# Add CUDA files once they are compiled from cu to .o
+if(ScalFMM_USE_CUDA)
+    # Find all the CU files in my project
+    file(GLOB_RECURSE source_cu_files ./*.cu)
+ 
+    # Iterate and add builind command for each file
+    set( SCALFMM_CUDA_SOURCES "" )
+    FOREACH (_file ${source_cu_files})
+ 
+        GET_FILENAME_COMPONENT (_filewe ${_file} NAME_WE)
+        SET (_filehpp_output ${CMAKE_CURRENT_BINARY_DIR}/${_filewe}.o)
+ 
+        ADD_CUSTOM_COMMAND(OUTPUT  ${_filehpp_output}
+                  DEPENDS ${_file}
+                  COMMAND echo ARGS Compiling ${_filewe}
+                  COMMAND nvcc ARGS -c ${_file} -o ${_filehpp_output} ${CUSTOM_CUDA_FLAGS})
+ 
+        LIST (APPEND SCALFMM_CUDA_SOURCES ${_filehpp_output})
+    ENDFOREACH ()
+ 
+    MESSAGE( STATUS "SCALFMM_CUDA_SOURCES          = ${SCALFMM_CUDA_SOURCES}" )
+endif()
+
 # Adding cpp files to project
 add_library(
 	scalfmm
 	STATIC
 	${source_lib_files}
+	${SCALFMM_CUDA_SOURCES}
 )
 
 # Add blas library (even if it is set to off)