CMake/Modules/FindOpenMP.cmake

193 lines
5.8 KiB
CMake

#.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_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 <Andre.Brodtkorb@ifi.uio.no>
# Copyright 2012 Rolf Eike Beer <eike@sf-mail.de>
#
# 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 <omp.h>
int main() {
#ifdef _OPENMP
return 0;
#else
breaks_on_purpose
#endif
}
")
# 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()
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()