modify CMakeLists.txt to support new CUDA sdk versions and compute capabilities

* add compilation support for P100 and GTX1080 GPUs (cuda/8.0, compute_6x)
* introduce conditional for handling list of CUDA compute architectures depending on CUDA sdk version

CMakeLists.txt

@@ -71,12 +71,20 @@ if (CUDA_FOUND)
         endif()
         set(CUDA_NVCC_FLAGS "${CUDA_NVCC_FLAGS};--use_fast_math;-ftz=true;-O4;-Xptxas -O4")
 
-#        list(APPEND CUDA_NVCC_FLAGS "-gencode=arch=compute_13,code=sm_13")
-        list(APPEND CUDA_NVCC_FLAGS "-gencode=arch=compute_20,code=sm_20")
-        list(APPEND CUDA_NVCC_FLAGS "-gencode=arch=compute_20,code=sm_21")
+        if (${CUDA_VERSION} LESS 7.0) 
+                list(APPEND CUDA_NVCC_FLAGS "-gencode=arch=compute_13,code=sm_13")
+        endif()
+        if (${CUDA_VERSION} LESS 8.5) 
+                list(APPEND CUDA_NVCC_FLAGS "-gencode=arch=compute_20,code=[sm_20,sm_21]")
+	endif()	
         list(APPEND CUDA_NVCC_FLAGS "-gencode=arch=compute_30,code=sm_30")
         list(APPEND CUDA_NVCC_FLAGS "-gencode=arch=compute_35,code=sm_35")
-        list(APPEND CUDA_NVCC_FLAGS "-gencode=arch=compute_52,code=sm_52")
+        if (NOT (${CUDA_VERSION} LESS 7.5)) 
+                list(APPEND CUDA_NVCC_FLAGS "-gencode=arch=compute_52,code=sm_52")
+	endif()
+        if (NOT (${CUDA_VERSION} LESS 8.0)) 
+		list(APPEND CUDA_NVCC_FLAGS "-gencode=arch=compute_60,code=[sm_60,sm_61]")
+	endif()
         add_definitions(-DWITH_CUDA)
         set (BIOEM_CUDA_STATUS "Found")
 endif()
@@ -160,6 +168,7 @@ message(STATUS "CUDA: ${BIOEM_CUDA_STATUS}")
 message(STATUS "OpenMP: ${BIOEM_OPENMP_STATUS}")
 message(STATUS "MPI: ${BIOEM_MPI_STATUS}")
 
+
 if (PRINT_CMAKE_VARIABLES)
         get_cmake_property(_variableNames VARIABLES)
         foreach (_variableName ${_variableNames})