#.rst: # FindOpenMP # ---------- # # Finds OpenMP support # # This module can be used to detect OpenMP support in a compiler. If # the compiler supports OpenMP, the flags required to compile with # OpenMP support are returned in variables for the different languages. # The variables may be empty if the compiler does not need a special # flag to support OpenMP. # # The following variables are set: # # :: # # OpenMP_C_FLAGS - flags to add to the C compiler for OpenMP support # OpenMP_CXX_FLAGS - flags to add to the CXX compiler for OpenMP support # OpenMP_Fortran_FLAGS - flags to add to the Fortran compiler for OpenMP support # OPENMP_FOUND - true if openmp is detected # # # # Supported compilers can be found at # http://openmp.org/wp/openmp-compilers/ #============================================================================= # Copyright 2009 Kitware, Inc. # Copyright 2008-2009 André Rigland Brodtkorb # Copyright 2012 Rolf Eike Beer # Copyright 2014 Nicolas Bock # # Distributed under the OSI-approved BSD License (the "License"); # see accompanying file Copyright.txt for details. # # This software is distributed WITHOUT ANY WARRANTY; without even the # implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. # See the License for more information. #============================================================================= # (To distribute this file outside of CMake, substitute the full # License text for the above reference.) set(_OPENMP_REQUIRED_VARS) set(CMAKE_REQUIRED_QUIET_SAVE ${CMAKE_REQUIRED_QUIET}) set(CMAKE_REQUIRED_QUIET ${OpenMP_FIND_QUIETLY}) function(_OPENMP_FLAG_CANDIDATES LANG) set(OpenMP_FLAG_CANDIDATES #Empty, if compiler automatically accepts openmp " " #GNU "-fopenmp" #Microsoft Visual Studio "/openmp" #Intel windows "-Qopenmp" #PathScale, Intel "-openmp" #Sun "-xopenmp" #HP "+Oopenmp" #IBM XL C/c++ "-qsmp" #Portland Group, MIPSpro "-mp" ) set(OMP_FLAG_GNU "-fopenmp") set(OMP_FLAG_HP "+Oopenmp") if(WIN32) set(OMP_FLAG_Intel "-Qopenmp") elseif(CMAKE_${LANG}_COMPILER_ID STREQUAL "Intel" AND "${CMAKE_${LANG}_COMPILER_VERSION}" VERSION_LESS "15.0.0.20140528") set(OMP_FLAG_Intel "-openmp") else() set(OMP_FLAG_Intel "-qopenmp") endif() set(OMP_FLAG_MIPSpro "-mp") set(OMP_FLAG_MSVC "/openmp") set(OMP_FLAG_PathScale "-openmp") set(OMP_FLAG_PGI "-mp") set(OMP_FLAG_SunPro "-xopenmp") set(OMP_FLAG_XL "-qsmp") set(OMP_FLAG_Cray " ") # Move the flag that matches the compiler to the head of the list, # this is faster and doesn't clutter the output that much. If that # flag doesn't work we will still try all. if(OMP_FLAG_${CMAKE_${LANG}_COMPILER_ID}) list(REMOVE_ITEM OpenMP_FLAG_CANDIDATES "${OMP_FLAG_${CMAKE_${LANG}_COMPILER_ID}}") list(INSERT OpenMP_FLAG_CANDIDATES 0 "${OMP_FLAG_${CMAKE_${LANG}_COMPILER_ID}}") endif() set(OpenMP_${LANG}_FLAG_CANDIDATES "${OpenMP_FLAG_CANDIDATES}" PARENT_SCOPE) endfunction() # sample openmp source code to test set(OpenMP_C_TEST_SOURCE " #include int main() { #ifdef _OPENMP return 0; #else breaks_on_purpose #endif } ") # same in Fortran set(OpenMP_Fortran_TEST_SOURCE " program test use omp_lib integer :: n n = omp_get_num_threads() end program test " ) # check c compiler if(CMAKE_C_COMPILER_LOADED) # if these are set then do not try to find them again, # by avoiding any try_compiles for the flags if(OpenMP_C_FLAGS) unset(OpenMP_C_FLAG_CANDIDATES) else() _OPENMP_FLAG_CANDIDATES("C") include(${CMAKE_CURRENT_LIST_DIR}/CheckCSourceCompiles.cmake) endif() foreach(FLAG IN LISTS OpenMP_C_FLAG_CANDIDATES) set(SAFE_CMAKE_REQUIRED_FLAGS "${CMAKE_REQUIRED_FLAGS}") set(CMAKE_REQUIRED_FLAGS "${FLAG}") unset(OpenMP_FLAG_DETECTED CACHE) if(NOT CMAKE_REQUIRED_QUIET) message(STATUS "Try OpenMP C flag = [${FLAG}]") endif() check_c_source_compiles("${OpenMP_C_TEST_SOURCE}" OpenMP_FLAG_DETECTED) set(CMAKE_REQUIRED_FLAGS "${SAFE_CMAKE_REQUIRED_FLAGS}") if(OpenMP_FLAG_DETECTED) set(OpenMP_C_FLAGS_INTERNAL "${FLAG}") break() endif() endforeach() set(OpenMP_C_FLAGS "${OpenMP_C_FLAGS_INTERNAL}" CACHE STRING "C compiler flags for OpenMP parallization") list(APPEND _OPENMP_REQUIRED_VARS OpenMP_C_FLAGS) unset(OpenMP_C_FLAG_CANDIDATES) endif() # check cxx compiler if(CMAKE_CXX_COMPILER_LOADED) # if these are set then do not try to find them again, # by avoiding any try_compiles for the flags if(OpenMP_CXX_FLAGS) unset(OpenMP_CXX_FLAG_CANDIDATES) else() _OPENMP_FLAG_CANDIDATES("CXX") include(${CMAKE_CURRENT_LIST_DIR}/CheckCXXSourceCompiles.cmake) # use the same source for CXX as C for now set(OpenMP_CXX_TEST_SOURCE ${OpenMP_C_TEST_SOURCE}) endif() foreach(FLAG IN LISTS OpenMP_CXX_FLAG_CANDIDATES) set(SAFE_CMAKE_REQUIRED_FLAGS "${CMAKE_REQUIRED_FLAGS}") set(CMAKE_REQUIRED_FLAGS "${FLAG}") unset(OpenMP_FLAG_DETECTED CACHE) if(NOT CMAKE_REQUIRED_QUIET) message(STATUS "Try OpenMP CXX flag = [${FLAG}]") endif() check_cxx_source_compiles("${OpenMP_CXX_TEST_SOURCE}" OpenMP_FLAG_DETECTED) set(CMAKE_REQUIRED_FLAGS "${SAFE_CMAKE_REQUIRED_FLAGS}") if(OpenMP_FLAG_DETECTED) set(OpenMP_CXX_FLAGS_INTERNAL "${FLAG}") break() endif() endforeach() set(OpenMP_CXX_FLAGS "${OpenMP_CXX_FLAGS_INTERNAL}" CACHE STRING "C++ compiler flags for OpenMP parallization") list(APPEND _OPENMP_REQUIRED_VARS OpenMP_CXX_FLAGS) unset(OpenMP_CXX_FLAG_CANDIDATES) unset(OpenMP_CXX_TEST_SOURCE) endif() # check Fortran compiler if(CMAKE_Fortran_COMPILER_LOADED) # if these are set then do not try to find them again, # by avoiding any try_compiles for the flags if(OpenMP_Fortran_FLAGS) unset(OpenMP_Fortran_FLAG_CANDIDATES) else() _OPENMP_FLAG_CANDIDATES("Fortran") include(${CMAKE_CURRENT_LIST_DIR}/CheckFortranSourceCompiles.cmake) endif() foreach(FLAG IN LISTS OpenMP_Fortran_FLAG_CANDIDATES) set(SAFE_CMAKE_REQUIRED_FLAGS "${CMAKE_REQUIRED_FLAGS}") set(CMAKE_REQUIRED_FLAGS "${FLAG}") unset(OpenMP_FLAG_DETECTED CACHE) if(NOT CMAKE_REQUIRED_QUIET) message(STATUS "Try OpenMP Fortran flag = [${FLAG}]") endif() check_fortran_source_compiles("${OpenMP_Fortran_TEST_SOURCE}" OpenMP_FLAG_DETECTED) set(CMAKE_REQUIRED_FLAGS "${SAFE_CMAKE_REQUIRED_FLAGS}") if(OpenMP_FLAG_DETECTED) set(OpenMP_Fortran_FLAGS_INTERNAL "${FLAG}") break() endif() endforeach() set(OpenMP_Fortran_FLAGS "${OpenMP_Fortran_FLAGS_INTERNAL}" CACHE STRING "Fortran compiler flags for OpenMP parallization") list(APPEND _OPENMP_REQUIRED_VARS OpenMP_Fortran_FLAGS) unset(OpenMP_Fortran_FLAG_CANDIDATES) unset(OpenMP_Fortran_TEST_SOURCE) endif() set(CMAKE_REQUIRED_QUIET ${CMAKE_REQUIRED_QUIET_SAVE}) if(_OPENMP_REQUIRED_VARS) include(${CMAKE_CURRENT_LIST_DIR}/FindPackageHandleStandardArgs.cmake) find_package_handle_standard_args(OpenMP REQUIRED_VARS ${_OPENMP_REQUIRED_VARS}) mark_as_advanced(${_OPENMP_REQUIRED_VARS}) unset(_OPENMP_REQUIRED_VARS) else() message(SEND_ERROR "FindOpenMP requires C or CXX language to be enabled") endif()