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Diffstat (limited to 'Modules/FindMPI.cmake')
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diff --git a/Modules/FindMPI.cmake b/Modules/FindMPI.cmake new file mode 100644 index 000000000..ae50ca7b9 --- /dev/null +++ b/Modules/FindMPI.cmake @@ -0,0 +1,631 @@ +# - Find a Message Passing Interface (MPI) implementation +# The Message Passing Interface (MPI) is a library used to write +# high-performance distributed-memory parallel applications, and +# is typically deployed on a cluster. MPI is a standard interface +# (defined by the MPI forum) for which many implementations are +# available. All of them have somewhat different include paths, +# libraries to link against, etc., and this module tries to smooth +# out those differences. +# +# === Variables === +# +# This module will set the following variables per language in your project, +# where <lang> is one of C, CXX, or Fortran: +# MPI_<lang>_FOUND TRUE if FindMPI found MPI flags for <lang> +# MPI_<lang>_COMPILER MPI Compiler wrapper for <lang> +# MPI_<lang>_COMPILE_FLAGS Compilation flags for MPI programs +# MPI_<lang>_INCLUDE_PATH Include path(s) for MPI header +# MPI_<lang>_LINK_FLAGS Linking flags for MPI programs +# MPI_<lang>_LIBRARIES All libraries to link MPI programs against +# Additionally, FindMPI sets the following variables for running MPI +# programs from the command line: +# MPIEXEC Executable for running MPI programs +# MPIEXEC_NUMPROC_FLAG Flag to pass to MPIEXEC before giving +# it the number of processors to run on +# MPIEXEC_PREFLAGS Flags to pass to MPIEXEC directly +# before the executable to run. +# MPIEXEC_POSTFLAGS Flags to pass to MPIEXEC after other flags +# === Usage === +# +# To use this module, simply call FindMPI from a CMakeLists.txt file, or +# run find_package(MPI), then run CMake. If you are happy with the auto- +# detected configuration for your language, then you're done. If not, you +# have two options: +# 1. Set MPI_<lang>_COMPILER to the MPI wrapper (mpicc, etc.) of your +# choice and reconfigure. FindMPI will attempt to determine all the +# necessary variables using THAT compiler's compile and link flags. +# 2. If this fails, or if your MPI implementation does not come with +# a compiler wrapper, then set both MPI_<lang>_LIBRARIES and +# MPI_<lang>_INCLUDE_PATH. You may also set any other variables +# listed above, but these two are required. This will circumvent +# autodetection entirely. +# When configuration is successful, MPI_<lang>_COMPILER will be set to the +# compiler wrapper for <lang>, if it was found. MPI_<lang>_FOUND and other +# variables above will be set if any MPI implementation was found for <lang>, +# regardless of whether a compiler was found. +# +# When using MPIEXEC to execute MPI applications, you should typically use +# all of the MPIEXEC flags as follows: +# ${MPIEXEC} ${MPIEXEC_NUMPROC_FLAG} PROCS +# ${MPIEXEC_PREFLAGS} EXECUTABLE ${MPIEXEC_POSTFLAGS} ARGS +# where PROCS is the number of processors on which to execute the program, +# EXECUTABLE is the MPI program, and ARGS are the arguments to pass to the +# MPI program. +# +# === Backward Compatibility === +# +# For backward compatibility with older versions of FindMPI, these +# variables are set, but deprecated: +# MPI_FOUND MPI_COMPILER MPI_LIBRARY +# MPI_COMPILE_FLAGS MPI_INCLUDE_PATH MPI_EXTRA_LIBRARY +# MPI_LINK_FLAGS MPI_LIBRARIES +# In new projects, please use the MPI_<lang>_XXX equivalents. + +#============================================================================= +# Copyright 2001-2011 Kitware, Inc. +# Copyright 2010-2011 Todd Gamblin tgamblin@llnl.gov +# Copyright 2001-2009 Dave Partyka +# +# Distributed under the OSI-approved BSD License (the "License"); +# see accompanying file Copyright.txt for details. +# +# This software is distributed WITHOUT ANY WARRANTY; without even the +# implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. +# See the License for more information. +#============================================================================= +# (To distribute this file outside of CMake, substitute the full +# License text for the above reference.) + +# include this to handle the QUIETLY and REQUIRED arguments +include(${CMAKE_CURRENT_LIST_DIR}/FindPackageHandleStandardArgs.cmake) +include(GetPrerequisites) + +# +# This part detects MPI compilers, attempting to wade through the mess of compiler names in +# a sensible way. +# +# The compilers are detected in this order: +# +# 1. Try to find the most generic availble MPI compiler, as this is usually set up by +# cluster admins. e.g., if plain old mpicc is available, we'll use it and assume it's +# the right compiler. +# +# 2. If a generic mpicc is NOT found, then we attempt to find one that matches +# CMAKE_<lang>_COMPILER_ID. e.g. if you are using XL compilers, we'll try to find mpixlc +# and company, but not mpiicc. This hopefully prevents toolchain mismatches. +# +# If you want to force a particular MPI compiler other than what we autodetect (e.g. if you +# want to compile regular stuff with GNU and parallel stuff with Intel), you can always set +# your favorite MPI_<lang>_COMPILER explicitly and this stuff will be ignored. +# + +# Start out with the generic MPI compiler names, as these are most commonly used. +set(_MPI_C_COMPILER_NAMES mpicc mpcc mpicc_r mpcc_r) +set(_MPI_CXX_COMPILER_NAMES mpicxx mpiCC mpcxx mpCC mpic++ mpc++ + mpicxx_r mpiCC_r mpcxx_r mpCC_r mpic++_r mpc++_r) +set(_MPI_Fortran_COMPILER_NAMES mpif95 mpif95_r mpf95 mpf95_r + mpif90 mpif90_r mpf90 mpf90_r + mpif77 mpif77_r mpf77 mpf77_r) + +# GNU compiler names +set(_MPI_GNU_C_COMPILER_NAMES mpigcc mpgcc mpigcc_r mpgcc_r) +set(_MPI_GNU_CXX_COMPILER_NAMES mpig++ mpg++ mpig++_r mpg++_r) +set(_MPI_GNU_Fortran_COMPILER_NAMES mpigfortran mpgfortran mpigfortran_r mpgfortran_r + mpig77 mpig77_r mpg77 mpg77_r) + +# Intel MPI compiler names +set(_MPI_Intel_C_COMPILER_NAMES mpiicc) +set(_MPI_Intel_CXX_COMPILER_NAMES mpiicpc mpiicxx mpiic++ mpiiCC) +set(_MPI_Intel_Fortran_COMPILER_NAMES mpiifort mpiif95 mpiif90 mpiif77) + +# PGI compiler names +set(_MPI_PGI_C_COMPILER_NAMES mpipgcc mppgcc) +set(_MPI_PGI_CXX_COMPILER_NAMES mpipgCC mppgCC) +set(_MPI_PGI_Fortran_COMPILER_NAMES mpipgf95 mpipgf90 mppgf95 mppgf90 mpipgf77 mppgf77) + +# XLC MPI Compiler names +set(_MPI_XL_C_COMPILER_NAMES mpxlc mpxlc_r mpixlc mpixlc_r) +set(_MPI_XL_CXX_COMPILER_NAMES mpixlcxx mpixlC mpixlc++ mpxlcxx mpxlc++ mpixlc++ mpxlCC + mpixlcxx_r mpixlC_r mpixlc++_r mpxlcxx_r mpxlc++_r mpixlc++_r mpxlCC_r) +set(_MPI_XL_Fortran_COMPILER_NAMES mpixlf95 mpixlf95_r mpxlf95 mpxlf95_r + mpixlf90 mpixlf90_r mpxlf90 mpxlf90_r + mpixlf77 mpixlf77_r mpxlf77 mpxlf77_r + mpixlf mpixlf_r mpxlf mpxlf_r) + +# append vendor-specific compilers to the list if we either don't know the compiler id, +# or if we know it matches the regular compiler. +foreach (lang C CXX Fortran) + foreach (id GNU Intel PGI XL) + if (NOT CMAKE_${lang}_COMPILER_ID OR "${CMAKE_${lang}_COMPILER_ID}" STREQUAL "${id}") + list(APPEND _MPI_${lang}_COMPILER_NAMES ${_MPI_${id}_${lang}_COMPILER_NAMES}) + endif() + unset(_MPI_${id}_${lang}_COMPILER_NAMES) # clean up the namespace here + endforeach() +endforeach() + + +# Names to try for MPI exec +set(_MPI_EXEC_NAMES mpiexec mpirun lamexec srun) + +# Grab the path to MPI from the registry if we're on windows. +set(_MPI_PREFIX_PATH) +if(WIN32) + list(APPEND _MPI_PREFIX_PATH "[HKEY_LOCAL_MACHINE\\SOFTWARE\\MPICH\\SMPD;binary]/..") + list(APPEND _MPI_PREFIX_PATH "[HKEY_LOCAL_MACHINE\\SOFTWARE\\MPICH2;Path]") + list(APPEND _MPI_PREFIX_PATH "$ENV{ProgramW6432}/MPICH2/") +endif() + +# Build a list of prefixes to search for MPI. +foreach(SystemPrefixDir ${CMAKE_SYSTEM_PREFIX_PATH}) + foreach(MpiPackageDir ${_MPI_PREFIX_PATH}) + if(EXISTS ${SystemPrefixDir}/${MpiPackageDir}) + list(APPEND _MPI_PREFIX_PATH "${SystemPrefixDir}/${MpiPackageDir}") + endif() + endforeach() +endforeach() + + +# +# interrogate_mpi_compiler(lang try_libs) +# +# Attempts to extract compiler and linker args from an MPI compiler. The arguments set +# by this function are: +# +# MPI_<lang>_INCLUDE_PATH MPI_<lang>_LINK_FLAGS MPI_<lang>_FOUND +# MPI_<lang>_COMPILE_FLAGS MPI_<lang>_LIBRARIES +# +# MPI_<lang>_COMPILER must be set beforehand to the absolute path to an MPI compiler for +# <lang>. Additionally, MPI_<lang>_INCLUDE_PATH and MPI_<lang>_LIBRARIES may be set +# to skip autodetection. +# +# If try_libs is TRUE, this will also attempt to find plain MPI libraries in the usual +# way. In general, this is not as effective as interrogating the compilers, as it +# ignores language-specific flags and libraries. However, some MPI implementations +# (Windows implementations) do not have compiler wrappers, so this approach must be used. +# +function (interrogate_mpi_compiler lang try_libs) + # MPI_${lang}_NO_INTERROGATE will be set to a compiler name when the *regular* compiler was + # discovered to be the MPI compiler. This happens on machines like the Cray XE6 that use + # modules to set cc, CC, and ftn to the MPI compilers. If the user force-sets another MPI + # compiler, MPI_${lang}_COMPILER won't be equal to MPI_${lang}_NO_INTERROGATE, and we'll + # inspect that compiler anew. This allows users to set new compilers w/o rm'ing cache. + string(COMPARE NOTEQUAL "${MPI_${lang}_NO_INTERROGATE}" "${MPI_${lang}_COMPILER}" interrogate) + + # If MPI is set already in the cache, don't bother with interrogating the compiler. + if (interrogate AND ((NOT MPI_${lang}_INCLUDE_PATH) OR (NOT MPI_${lang}_LIBRARIES))) + if (MPI_${lang}_COMPILER) + # Check whether the -showme:compile option works. This indicates that we have either OpenMPI + # or a newer version of LAM-MPI, and implies that -showme:link will also work. + execute_process( + COMMAND ${MPI_${lang}_COMPILER} -showme:compile + OUTPUT_VARIABLE MPI_COMPILE_CMDLINE OUTPUT_STRIP_TRAILING_WHITESPACE + ERROR_VARIABLE MPI_COMPILE_CMDLINE ERROR_STRIP_TRAILING_WHITESPACE + RESULT_VARIABLE MPI_COMPILER_RETURN) + + if (MPI_COMPILER_RETURN EQUAL 0) + # If we appear to have -showme:compile, then we should + # also have -showme:link. Try it. + execute_process( + COMMAND ${MPI_${lang}_COMPILER} -showme:link + OUTPUT_VARIABLE MPI_LINK_CMDLINE OUTPUT_STRIP_TRAILING_WHITESPACE + ERROR_VARIABLE MPI_LINK_CMDLINE ERROR_STRIP_TRAILING_WHITESPACE + RESULT_VARIABLE MPI_COMPILER_RETURN) + + if (MPI_COMPILER_RETURN EQUAL 0) + # We probably have -showme:incdirs and -showme:libdirs as well, + # so grab that while we're at it. + execute_process( + COMMAND ${MPI_${lang}_COMPILER} -showme:incdirs + OUTPUT_VARIABLE MPI_INCDIRS OUTPUT_STRIP_TRAILING_WHITESPACE + ERROR_VARIABLE MPI_INCDIRS ERROR_STRIP_TRAILING_WHITESPACE) + + execute_process( + COMMAND ${MPI_${lang}_COMPILER} -showme:libdirs + OUTPUT_VARIABLE MPI_LIBDIRS OUTPUT_STRIP_TRAILING_WHITESPACE + ERROR_VARIABLE MPI_LIBDIRS ERROR_STRIP_TRAILING_WHITESPACE) + + else() + # reset things here if something went wrong. + set(MPI_COMPILE_CMDLINE) + set(MPI_LINK_CMDLINE) + endif() + endif () + + # Older versions of LAM-MPI have "-showme". Try to find that. + if (NOT MPI_COMPILER_RETURN EQUAL 0) + execute_process( + COMMAND ${MPI_${lang}_COMPILER} -showme + OUTPUT_VARIABLE MPI_COMPILE_CMDLINE OUTPUT_STRIP_TRAILING_WHITESPACE + ERROR_VARIABLE MPI_COMPILE_CMDLINE ERROR_STRIP_TRAILING_WHITESPACE + RESULT_VARIABLE MPI_COMPILER_RETURN) + endif() + + # MVAPICH uses -compile-info and -link-info. Try them. + if (NOT MPI_COMPILER_RETURN EQUAL 0) + execute_process( + COMMAND ${MPI_${lang}_COMPILER} -compile-info + OUTPUT_VARIABLE MPI_COMPILE_CMDLINE OUTPUT_STRIP_TRAILING_WHITESPACE + ERROR_VARIABLE MPI_COMPILE_CMDLINE ERROR_STRIP_TRAILING_WHITESPACE + RESULT_VARIABLE MPI_COMPILER_RETURN) + + # If we have compile-info, also have link-info. + if (MPI_COMPILER_RETURN EQUAL 0) + execute_process( + COMMAND ${MPI_${lang}_COMPILER} -link-info + OUTPUT_VARIABLE MPI_LINK_CMDLINE OUTPUT_STRIP_TRAILING_WHITESPACE + ERROR_VARIABLE MPI_LINK_CMDLINE ERROR_STRIP_TRAILING_WHITESPACE + RESULT_VARIABLE MPI_COMPILER_RETURN) + endif() + + # make sure we got compile and link. Reset vars if something's wrong. + if (NOT MPI_COMPILER_RETURN EQUAL 0) + set(MPI_COMPILE_CMDLINE) + set(MPI_LINK_CMDLINE) + endif() + endif() + + # MPICH just uses "-show". Try it. + if (NOT MPI_COMPILER_RETURN EQUAL 0) + execute_process( + COMMAND ${MPI_${lang}_COMPILER} -show + OUTPUT_VARIABLE MPI_COMPILE_CMDLINE OUTPUT_STRIP_TRAILING_WHITESPACE + ERROR_VARIABLE MPI_COMPILE_CMDLINE ERROR_STRIP_TRAILING_WHITESPACE + RESULT_VARIABLE MPI_COMPILER_RETURN) + endif() + + if (MPI_COMPILER_RETURN EQUAL 0) + # We have our command lines, but we might need to copy MPI_COMPILE_CMDLINE + # into MPI_LINK_CMDLINE, if we didn't find the link line. + if (NOT MPI_LINK_CMDLINE) + set(MPI_LINK_CMDLINE ${MPI_COMPILE_CMDLINE}) + endif() + else() + message(STATUS "Unable to determine MPI from MPI driver ${MPI_${lang}_COMPILER}") + set(MPI_COMPILE_CMDLINE) + set(MPI_LINK_CMDLINE) + endif() + + # Here, we're done with the interrogation part, and we'll try to extract args we care + # about from what we learned from the compiler wrapper scripts. + + # If interrogation came back with something, extract our variable from the MPI command line + if (MPI_COMPILE_CMDLINE OR MPI_LINK_CMDLINE) + # Extract compile flags from the compile command line. + string(REGEX MATCHALL "(^| )-[Df]([^\" ]+|\"[^\"]+\")" MPI_ALL_COMPILE_FLAGS "${MPI_COMPILE_CMDLINE}") + set(MPI_COMPILE_FLAGS_WORK) + + foreach(FLAG ${MPI_ALL_COMPILE_FLAGS}) + if (MPI_COMPILE_FLAGS_WORK) + set(MPI_COMPILE_FLAGS_WORK "${MPI_COMPILE_FLAGS_WORK} ${FLAG}") + else() + set(MPI_COMPILE_FLAGS_WORK ${FLAG}) + endif() + endforeach() + + # Extract include paths from compile command line + string(REGEX MATCHALL "(^| )-I([^\" ]+|\"[^\"]+\")" MPI_ALL_INCLUDE_PATHS "${MPI_COMPILE_CMDLINE}") + foreach(IPATH ${MPI_ALL_INCLUDE_PATHS}) + string(REGEX REPLACE "^ ?-I" "" IPATH ${IPATH}) + string(REGEX REPLACE "//" "/" IPATH ${IPATH}) + list(APPEND MPI_INCLUDE_PATH_WORK ${IPATH}) + endforeach() + + # try using showme:incdirs if extracting didn't work. + if (NOT MPI_INCLUDE_PATH_WORK) + set(MPI_INCLUDE_PATH_WORK ${MPI_INCDIRS}) + separate_arguments(MPI_INCLUDE_PATH_WORK) + endif() + + # If all else fails, just search for mpi.h in the normal include paths. + if (NOT MPI_INCLUDE_PATH_WORK) + set(MPI_HEADER_PATH "MPI_HEADER_PATH-NOTFOUND" CACHE FILEPATH "Cleared" FORCE) + find_path(MPI_HEADER_PATH mpi.h + HINTS ${_MPI_BASE_DIR} ${_MPI_PREFIX_PATH} + PATH_SUFFIXES include) + set(MPI_INCLUDE_PATH_WORK ${MPI_HEADER_PATH}) + endif() + + # Extract linker paths from the link command line + string(REGEX MATCHALL "(^| |-Wl,)-L([^\" ]+|\"[^\"]+\")" MPI_ALL_LINK_PATHS "${MPI_LINK_CMDLINE}") + set(MPI_LINK_PATH) + foreach(LPATH ${MPI_ALL_LINK_PATHS}) + string(REGEX REPLACE "^(| |-Wl,)-L" "" LPATH ${LPATH}) + string(REGEX REPLACE "//" "/" LPATH ${LPATH}) + list(APPEND MPI_LINK_PATH ${LPATH}) + endforeach() + + # try using showme:libdirs if extracting didn't work. + if (NOT MPI_LINK_PATH) + set(MPI_LINK_PATH ${MPI_LIBDIRS}) + separate_arguments(MPI_LINK_PATH) + endif() + + # Extract linker flags from the link command line + string(REGEX MATCHALL "(^| )-Wl,([^\" ]+|\"[^\"]+\")" MPI_ALL_LINK_FLAGS "${MPI_LINK_CMDLINE}") + set(MPI_LINK_FLAGS_WORK) + foreach(FLAG ${MPI_ALL_LINK_FLAGS}) + if (MPI_LINK_FLAGS_WORK) + set(MPI_LINK_FLAGS_WORK "${MPI_LINK_FLAGS_WORK} ${FLAG}") + else() + set(MPI_LINK_FLAGS_WORK ${FLAG}) + endif() + endforeach() + + # Extract the set of libraries to link against from the link command + # line + string(REGEX MATCHALL "(^| )-l([^\" ]+|\"[^\"]+\")" MPI_LIBNAMES "${MPI_LINK_CMDLINE}") + # add the compiler implicit directories because some compilers + # such as the intel compiler have libraries that show up + # in the showme list that can only be found in the implicit + # link directories of the compiler. Do this for C++ and C + # compilers if the implicit link directories are defined. + if (DEFINED CMAKE_CXX_IMPLICIT_LINK_DIRECTORIES) + set(MPI_LINK_PATH + "${MPI_LINK_PATH};${CMAKE_CXX_IMPLICIT_LINK_DIRECTORIES}") + endif () + + if (DEFINED CMAKE_C_IMPLICIT_LINK_DIRECTORIES) + set(MPI_LINK_PATH + "${MPI_LINK_PATH};${CMAKE_C_IMPLICIT_LINK_DIRECTORIES}") + endif () + + # Determine full path names for all of the libraries that one needs + # to link against in an MPI program + foreach(LIB ${MPI_LIBNAMES}) + string(REGEX REPLACE "^ ?-l" "" LIB ${LIB}) + # MPI_LIB is cached by find_library, but we don't want that. Clear it first. + set(MPI_LIB "MPI_LIB-NOTFOUND" CACHE FILEPATH "Cleared" FORCE) + find_library(MPI_LIB NAMES ${LIB} HINTS ${MPI_LINK_PATH}) + + if (MPI_LIB) + list(APPEND MPI_LIBRARIES_WORK ${MPI_LIB}) + elseif (NOT MPI_FIND_QUIETLY) + message(WARNING "Unable to find MPI library ${LIB}") + endif() + endforeach() + + # Sanity check MPI_LIBRARIES to make sure there are enough libraries + list(LENGTH MPI_LIBRARIES_WORK MPI_NUMLIBS) + list(LENGTH MPI_LIBNAMES MPI_NUMLIBS_EXPECTED) + if (NOT MPI_NUMLIBS EQUAL MPI_NUMLIBS_EXPECTED) + set(MPI_LIBRARIES_WORK "MPI_${lang}_LIBRARIES-NOTFOUND") + endif() + endif() + + elseif(try_libs) + # If we didn't have an MPI compiler script to interrogate, attempt to find everything + # with plain old find functions. This is nasty because MPI implementations have LOTS of + # different library names, so this section isn't going to be very generic. We need to + # make sure it works for MS MPI, though, since there are no compiler wrappers for that. + find_path(MPI_HEADER_PATH mpi.h + HINTS ${_MPI_BASE_DIR} ${_MPI_PREFIX_PATH} + PATH_SUFFIXES include Inc) + set(MPI_INCLUDE_PATH_WORK ${MPI_HEADER_PATH}) + + # Decide between 32-bit and 64-bit libraries for Microsoft's MPI + if("${CMAKE_SIZEOF_VOID_P}" EQUAL 8) + set(MS_MPI_ARCH_DIR amd64) + else() + set(MS_MPI_ARCH_DIR i386) + endif() + + set(MPI_LIB "MPI_LIB-NOTFOUND" CACHE FILEPATH "Cleared" FORCE) + find_library(MPI_LIB + NAMES mpi mpich mpich2 msmpi + HINTS ${_MPI_BASE_DIR} ${_MPI_PREFIX_PATH} + PATH_SUFFIXES lib lib/${MS_MPI_ARCH_DIR} Lib Lib/${MS_MPI_ARCH_DIR}) + set(MPI_LIBRARIES_WORK ${MPI_LIB}) + + # Right now, we only know about the extra libs for C++. + # We could add Fortran here (as there is usually libfmpich, etc.), but + # this really only has to work with MS MPI on Windows. + # Assume that other MPI's are covered by the compiler wrappers. + if (${lang} STREQUAL CXX) + set(MPI_LIB "MPI_LIB-NOTFOUND" CACHE FILEPATH "Cleared" FORCE) + find_library(MPI_LIB + NAMES mpi++ mpicxx cxx mpi_cxx + HINTS ${_MPI_BASE_DIR} ${_MPI_PREFIX_PATH} + PATH_SUFFIXES lib) + if (MPI_LIBRARIES_WORK AND MPI_LIB) + list(APPEND MPI_LIBRARIES_WORK ${MPI_LIB}) + endif() + endif() + + if (NOT MPI_LIBRARIES_WORK) + set(MPI_LIBRARIES_WORK "MPI_${lang}_LIBRARIES-NOTFOUND") + endif() + endif() + + # If we found MPI, set up all of the appropriate cache entries + set(MPI_${lang}_COMPILE_FLAGS ${MPI_COMPILE_FLAGS_WORK} CACHE STRING "MPI ${lang} compilation flags" FORCE) + set(MPI_${lang}_INCLUDE_PATH ${MPI_INCLUDE_PATH_WORK} CACHE STRING "MPI ${lang} include path" FORCE) + set(MPI_${lang}_LINK_FLAGS ${MPI_LINK_FLAGS_WORK} CACHE STRING "MPI ${lang} linking flags" FORCE) + set(MPI_${lang}_LIBRARIES ${MPI_LIBRARIES_WORK} CACHE STRING "MPI ${lang} libraries to link against" FORCE) + mark_as_advanced(MPI_${lang}_COMPILE_FLAGS MPI_${lang}_INCLUDE_PATH MPI_${lang}_LINK_FLAGS MPI_${lang}_LIBRARIES) + + # clear out our temporary lib/header detectionv variable here. + set(MPI_LIB "MPI_LIB-NOTFOUND" CACHE INTERNAL "Scratch variable for MPI lib detection" FORCE) + set(MPI_HEADER_PATH "MPI_HEADER_PATH-NOTFOUND" CACHE INTERNAL "Scratch variable for MPI header detection" FORCE) + endif() + + # finally set a found variable for each MPI language + if (MPI_${lang}_INCLUDE_PATH AND MPI_${lang}_LIBRARIES) + set(MPI_${lang}_FOUND TRUE PARENT_SCOPE) + else() + set(MPI_${lang}_FOUND FALSE PARENT_SCOPE) + endif() +endfunction() + + +# This function attempts to compile with the regular compiler, to see if MPI programs +# work with it. This is a last ditch attempt after we've tried interrogating mpicc and +# friends, and after we've tried to find generic libraries. Works on machines like +# Cray XE6, where the modules environment changes what MPI version cc, CC, and ftn use. +function(try_regular_compiler lang success) + set(scratch_directory ${CMAKE_CURRENT_BINARY_DIR}${CMAKE_FILES_DIRECTORY}) + if (${lang} STREQUAL Fortran) + set(test_file ${scratch_directory}/cmake_mpi_test.f90) + file(WRITE ${test_file} + "program hello\n" + "include 'mpif.h'\n" + "integer ierror\n" + "call MPI_INIT(ierror)\n" + "call MPI_FINALIZE(ierror)\n" + "end\n") + else() + if (${lang} STREQUAL CXX) + set(test_file ${scratch_directory}/cmake_mpi_test.cpp) + else() + set(test_file ${scratch_directory}/cmake_mpi_test.c) + endif() + file(WRITE ${test_file} + "#include <mpi.h>\n" + "int main(int argc, char **argv) {\n" + " MPI_Init(&argc, &argv);\n" + " MPI_Finalize();\n" + "}\n") + endif() + try_compile(compiler_has_mpi ${scratch_directory} ${test_file}) + if (compiler_has_mpi) + set(MPI_${lang}_NO_INTERROGATE ${CMAKE_${lang}_COMPILER} CACHE STRING "Whether to interrogate MPI ${lang} compiler" FORCE) + set(MPI_${lang}_COMPILER ${CMAKE_${lang}_COMPILER} CACHE STRING "MPI ${lang} compiler" FORCE) + set(MPI_${lang}_COMPILE_FLAGS "" CACHE STRING "MPI ${lang} compilation flags" FORCE) + set(MPI_${lang}_INCLUDE_PATH "" CACHE STRING "MPI ${lang} include path" FORCE) + set(MPI_${lang}_LINK_FLAGS "" CACHE STRING "MPI ${lang} linking flags" FORCE) + set(MPI_${lang}_LIBRARIES "" CACHE STRING "MPI ${lang} libraries to link against" FORCE) + endif() + set(${success} ${compiler_has_mpi} PARENT_SCOPE) + unset(compiler_has_mpi CACHE) +endfunction() + +# End definitions, commence real work here. + +# Most mpi distros have some form of mpiexec which gives us something we can reliably look for. +find_program(MPIEXEC + NAMES ${_MPI_EXEC_NAMES} + PATHS ${_MPI_PREFIX_PATH} + PATH_SUFFIXES bin + DOC "Executable for running MPI programs.") + +# call get_filename_component twice to remove mpiexec and the directory it exists in (typically bin). +# This gives us a fairly reliable base directory to search for /bin /lib and /include from. +get_filename_component(_MPI_BASE_DIR "${MPIEXEC}" PATH) +get_filename_component(_MPI_BASE_DIR "${_MPI_BASE_DIR}" PATH) + +set(MPIEXEC_NUMPROC_FLAG "-np" CACHE STRING "Flag used by MPI to specify the number of processes for MPIEXEC; the next option will be the number of processes.") +set(MPIEXEC_PREFLAGS "" CACHE STRING "These flags will be directly before the executable that is being run by MPIEXEC.") +set(MPIEXEC_POSTFLAGS "" CACHE STRING "These flags will come after all flags given to MPIEXEC.") +set(MPIEXEC_MAX_NUMPROCS "2" CACHE STRING "Maximum number of processors available to run MPI applications.") +mark_as_advanced(MPIEXEC MPIEXEC_NUMPROC_FLAG MPIEXEC_PREFLAGS MPIEXEC_POSTFLAGS MPIEXEC_MAX_NUMPROCS) + + +#============================================================================= +# Backward compatibility input hacks. Propagate the FindMPI hints to C and +# CXX if the respective new versions are not defined. Translate the old +# MPI_LIBRARY and MPI_EXTRA_LIBRARY to respective MPI_${lang}_LIBRARIES. +# +# Once we find the new variables, we translate them back into their old +# equivalents below. +foreach (lang C CXX) + # Old input variables. + set(_MPI_OLD_INPUT_VARS COMPILER COMPILE_FLAGS INCLUDE_PATH LINK_FLAGS) + + # Set new vars based on their old equivalents, if the new versions are not already set. + foreach (var ${_MPI_OLD_INPUT_VARS}) + if (NOT MPI_${lang}_${var} AND MPI_${var}) + set(MPI_${lang}_${var} "${MPI_${var}}") + endif() + endforeach() + + # Special handling for MPI_LIBRARY and MPI_EXTRA_LIBRARY, which we nixed in the + # new FindMPI. These need to be merged into MPI_<lang>_LIBRARIES + if (NOT MPI_${lang}_LIBRARIES AND (MPI_LIBRARY OR MPI_EXTRA_LIBRARY)) + set(MPI_${lang}_LIBRARIES ${MPI_LIBRARY} ${MPI_EXTRA_LIBRARY}) + endif() +endforeach() +#============================================================================= + + +# This loop finds the compilers and sends them off for interrogation. +foreach (lang C CXX Fortran) + if (CMAKE_${lang}_COMPILER_WORKS) + # If the user supplies a compiler *name* instead of an absolute path, assume that we need to find THAT compiler. + if (MPI_${lang}_COMPILER) + is_file_executable(MPI_${lang}_COMPILER MPI_COMPILER_IS_EXECUTABLE) + if (NOT MPI_COMPILER_IS_EXECUTABLE) + # Get rid of our default list of names and just search for the name the user wants. + set(_MPI_${lang}_COMPILER_NAMES ${MPI_${lang}_COMPILER}) + set(MPI_${lang}_COMPILER "MPI_${lang}_COMPILER-NOTFOUND" CACHE FILEPATH "Cleared" FORCE) + # If the user specifies a compiler, we don't want to try to search libraries either. + set(try_libs FALSE) + endif() + else() + set(try_libs TRUE) + endif() + + find_program(MPI_${lang}_COMPILER + NAMES ${_MPI_${lang}_COMPILER_NAMES} + PATHS "${MPI_HOME}/bin" "$ENV{MPI_HOME}/bin" ${_MPI_PREFIX_PATH}) + interrogate_mpi_compiler(${lang} ${try_libs}) + mark_as_advanced(MPI_${lang}_COMPILER) + + # last ditch try -- if nothing works so far, just try running the regular compiler and + # see if we can create an MPI executable. + set(regular_compiler_worked 0) + if (NOT MPI_${lang}_LIBRARIES OR NOT MPI_${lang}_INCLUDE_PATH) + try_regular_compiler(${lang} regular_compiler_worked) + endif() + + if (regular_compiler_worked) + find_package_handle_standard_args(MPI_${lang} DEFAULT_MSG MPI_${lang}_COMPILER) + else() + find_package_handle_standard_args(MPI_${lang} DEFAULT_MSG MPI_${lang}_LIBRARIES MPI_${lang}_INCLUDE_PATH) + endif() + endif() +endforeach() + + +#============================================================================= +# More backward compatibility stuff +# +# Bare MPI sans ${lang} vars are set to CXX then C, depending on what was found. +# This mimics the behavior of the old language-oblivious FindMPI. +set(_MPI_OLD_VARS FOUND COMPILER INCLUDE_PATH COMPILE_FLAGS LINK_FLAGS LIBRARIES) +if (MPI_CXX_FOUND) + foreach (var ${_MPI_OLD_VARS}) + set(MPI_${var} ${MPI_CXX_${var}}) + endforeach() +elseif (MPI_C_FOUND) + foreach (var ${_MPI_OLD_VARS}) + set(MPI_${var} ${MPI_C_${var}}) + endforeach() +else() + # Note that we might still have found Fortran, but you'll need to use MPI_Fortran_FOUND + set(MPI_FOUND FALSE) +endif() + +# Chop MPI_LIBRARIES into the old-style MPI_LIBRARY and MPI_EXTRA_LIBRARY, and set them in cache. +if (MPI_LIBRARIES) + list(GET MPI_LIBRARIES 0 MPI_LIBRARY_WORK) + set(MPI_LIBRARY ${MPI_LIBRARY_WORK} CACHE FILEPATH "MPI library to link against" FORCE) +else() + set(MPI_LIBRARY "MPI_LIBRARY-NOTFOUND" CACHE FILEPATH "MPI library to link against" FORCE) +endif() + +list(LENGTH MPI_LIBRARIES MPI_NUMLIBS) +if (MPI_NUMLIBS GREATER 1) + set(MPI_EXTRA_LIBRARY_WORK ${MPI_LIBRARIES}) + list(REMOVE_AT MPI_EXTRA_LIBRARY_WORK 0) + set(MPI_EXTRA_LIBRARY ${MPI_EXTRA_LIBRARY_WORK} CACHE STRING "Extra MPI libraries to link against" FORCE) +else() + set(MPI_EXTRA_LIBRARY "MPI_EXTRA_LIBRARY-NOTFOUND" CACHE STRING "Extra MPI libraries to link against" FORCE) +endif() +#============================================================================= + +# unset these vars to cleanup namespace +unset(_MPI_OLD_VARS) +unset(_MPI_PREFIX_PATH) +unset(_MPI_BASE_DIR) +foreach (lang C CXX Fortran) + unset(_MPI_${lang}_COMPILER_NAMES) +endforeach() |