Add openmp

Signed-off-by: Alexey Shvetsov <alexxy@gentoo.org>

diff --git a/CMakeLists.txt b/CMakeLists.txt
index fa4843274476e45bbb2c4f827fa4e17908766fa7..4d77447fcde763da612279f583ccf54935a93207 100644 (file)
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -18,6 +18,7 @@ set(CMAKE_RUNTIME_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR}/bin)
 # user explicitly sets what they want to get, and then need to provide a suffix
 # to match.
 option(GMX_DOUBLE "Use double precision" OFF)
+option(GMX_OPENMP "Enable OpenMP-based multithreading" ON)
 set(GMX_SUFFIX "" CACHE STRING "Suffix for the GROMACS installation to use (empty for default)")
 
 # This does not allow for a non-suffixed double-precision libgromacs, but
@@ -31,6 +32,7 @@ endif()
 find_package(GROMACS 2016 REQUIRED)
 gromacs_check_double(GMX_DOUBLE)
 gromacs_check_compiler(CXX)
+include(gmxManageOpenMP)
 
 add_definitions(${GROMACS_DEFINITIONS})
 
@@ -42,4 +44,12 @@ if (CMAKE_GENERATOR MATCHES "Visual Studio")
     set(CMAKE_C_FLAGS_DEBUG ${CMAKE_C_FLAGS_DEBUG} CACHE STRING "" FORCE)
 endif()
 
+if(NOT GMX_OPENMP)
+    #Unset all OpenMP flags in case OpenMP was disabled either by the user
+    #or because it was only partially detected (e.g. only for C but not C++ compiler)
+    unset(OpenMP_C_FLAGS CACHE)
+    unset(OpenMP_CXX_FLAGS CACHE)
+endif()
+
+
 add_subdirectory(src)

diff --git a/cmake/gmxManageOpenMP.cmake b/cmake/gmxManageOpenMP.cmake
new file mode 100644 (file)
index 0000000..4aad27a
--- /dev/null
+++ b/cmake/gmxManageOpenMP.cmake
@@ -0,0 +1,75 @@
+#
+# This file is part of the GROMACS molecular simulation package.
+#
+# Copyright (c) 2012,2013,2014,2015, by the GROMACS development team, led by
+# Mark Abraham, David van der Spoel, Berk Hess, and Erik Lindahl,
+# and including many others, as listed in the AUTHORS file in the
+# top-level source directory and at http://www.gromacs.org.
+#
+# GROMACS is free software; you can redistribute it and/or
+# modify it under the terms of the GNU Lesser General Public License
+# as published by the Free Software Foundation; either version 2.1
+# of the License, or (at your option) any later version.
+#
+# GROMACS is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+# Lesser General Public License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public
+# License along with GROMACS; if not, see
+# http://www.gnu.org/licenses, or write to the Free Software Foundation,
+# Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA.
+#
+# If you want to redistribute modifications to GROMACS, please
+# consider that scientific software is very special. Version
+# control is crucial - bugs must be traceable. We will be happy to
+# consider code for inclusion in the official distribution, but
+# derived work must not be called official GROMACS. Details are found
+# in the README & COPYING files - if they are missing, get the
+# official version at http://www.gromacs.org.
+#
+# To help us fund GROMACS development, we humbly ask that you cite
+# the research papers on the package. Check out http://www.gromacs.org.
+
+# Manage the OpenMP setup. This wrapper file checks for some known-bad compiler
+# versions before trying to detect OpenMP with the standard find-package-module,
+# and then does some additional tests for flags afterwards.
+
+if(GMX_OPENMP)
+    if(CMAKE_C_COMPILER_ID MATCHES "Cray" AND CMAKE_VERSION VERSION_LESS 3)
+        message(STATUS "OpenMP multithreading is not detected correctly for the Cray compiler with CMake before version 3.0 (see http://public.kitware.com/Bug/view.php?id=14567)")
+        set(GMX_OPENMP OFF CACHE BOOL
+            "OpenMP multithreading is not detected correctly for the Cray compiler with CMake before version 3.0 (see http://public.kitware.com/Bug/view.php?id=14567)" FORCE)
+    else()
+        # We should do OpenMP detection if we get here
+        # OpenMP check must come before other CFLAGS!
+        find_package(OpenMP)
+        if(OPENMP_FOUND)
+            # CMake on Windows doesn't support linker flags passed to target_link_libraries
+            # (i.e. it treats /openmp as \openmp library file). Also, no OpenMP linker flags are needed.
+            if(NOT (WIN32 AND NOT MINGW))
+                if(CMAKE_COMPILER_IS_GNUCC AND GMX_PREFER_STATIC_OPENMP AND NOT APPLE)
+                    set(OpenMP_LINKER_FLAGS "-Wl,-static -lgomp -lrt -Wl,-Bdynamic -lpthread")
+                    set(OpenMP_SHARED_LINKER_FLAGS "")
+                else()
+                    # Only set a linker flag if the user didn't set them manually
+                    if(NOT DEFINED OpenMP_LINKER_FLAGS)
+                        set(OpenMP_LINKER_FLAGS "${OpenMP_C_FLAGS}")
+                    endif()
+                    if(NOT DEFINED OpenMP_SHARED_LINKER_FLAGS)
+                        set(OpenMP_SHARED_LINKER_FLAGS "${OpenMP_C_FLAGS}")
+                    endif()
+                endif()
+            endif()
+            if(MINGW)
+                #GCC Bug 48659
+                set(OpenMP_C_FLAGS "${OpenMP_C_FLAGS} -mstackrealign")
+            endif()
+        else()
+            message(WARNING
+                    "The compiler you are using does not support OpenMP parallelism. This might hurt your performance a lot, in particular with GPUs. Try using a more recent version, or a different compiler. For now, we are proceeding by turning off OpenMP.")
+            set(GMX_OPENMP OFF CACHE STRING "Whether GROMACS will use OpenMP parallelism." FORCE)
+        endif()
+    endif()
+endif()

diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index 29794d0aac60d40cdac927fd75febdce33586dc3..825fde8b8aac7292de32315949847923fa37e118 100644 (file)
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -3,5 +3,5 @@ include_directories(
         ${GROMACS_INCLUDE_DIRS}
         ${CMAKE_SOURCE_DIR}/include)
 set_target_properties(domains PROPERTIES
-                      COMPILE_FLAGS "${GROMACS_CXX_FLAGS}")
+       COMPILE_FLAGS "${GROMACS_CXX_FLAGS} ${OpenMP_C_FLAGS}")
 target_link_libraries(domains ${GROMACS_LIBRARIES})