benchmark/CMakeLists.txt
Eric 207b9c7aec
Improve State packing: put important members on first cache line. (#527)
* Improve State packing: put important members on first cache line.

This patch does a few different things to ensure commonly accessed
data is on the first cache line of the `State` object.

First, it moves the `error_occurred_` member to reside after
the `started_` and `finished_` bools, since there was internal
padding there that was unused.

Second, it moves `batch_leftover_` and `max_iterations` further up
in the struct declaration. These variables are used in the calculation
of `iterations()` which users might call within the loop. Therefore
it's more important they exist on the first cache line.

Finally, this patch turns the bool members into bitfields. Although
this shouldn't have much of an effect currently, because padding is
still needed between the last bool and the first size_t, it should
help in future changes that require more "bool like" members.

* Remove bitfield change for now

* Move bools (and their padding) to end of "first cache line" vars.

I think it makes the most sense to move the padding required
following the group of bools to the end of the variables we want
on the first cache line.

This also means that the `total_iterations_` variable, which is the
most accessed, has the same address as the State object.

* Fix static assertion after moving bools
2018-02-14 13:44:41 -07:00

221 lines
8.8 KiB
CMake

cmake_minimum_required (VERSION 2.8.12)
project (benchmark)
foreach(p
CMP0054 # CMake 3.1
CMP0056 # export EXE_LINKER_FLAGS to try_run
CMP0057 # Support no if() IN_LIST operator
)
if(POLICY ${p})
cmake_policy(SET ${p} NEW)
endif()
endforeach()
option(BENCHMARK_ENABLE_TESTING "Enable testing of the benchmark library." ON)
option(BENCHMARK_ENABLE_EXCEPTIONS "Enable the use of exceptions in the benchmark library." ON)
option(BENCHMARK_ENABLE_LTO "Enable link time optimisation of the benchmark library." OFF)
option(BENCHMARK_USE_LIBCXX "Build and test using libc++ as the standard library." OFF)
option(BENCHMARK_BUILD_32_BITS "Build a 32 bit version of the library." OFF)
option(BENCHMARK_ENABLE_INSTALL "Enable installation of benchmark. (Projects embedding benchmark may want to turn this OFF.)" ON)
# Allow unmet dependencies to be met using CMake's ExternalProject mechanics, which
# may require downloading the source code.
option(BENCHMARK_DOWNLOAD_DEPENDENCIES "Allow the downloading and in-tree building of unmet dependencies" OFF)
# This option can be used to disable building and running unit tests which depend on gtest
# in cases where it is not possible to build or find a valid version of gtest.
option(BENCHMARK_ENABLE_GTEST_TESTS "Enable building the unit tests which depend on gtest" ON)
# Make sure we can import out CMake functions
list(APPEND CMAKE_MODULE_PATH "${CMAKE_CURRENT_SOURCE_DIR}/cmake/Modules")
list(APPEND CMAKE_MODULE_PATH "${CMAKE_CURRENT_SOURCE_DIR}/cmake")
# Read the git tags to determine the project version
include(GetGitVersion)
get_git_version(GIT_VERSION)
# Tell the user what versions we are using
string(REGEX MATCH "[0-9]+\\.[0-9]+\\.[0-9]+" VERSION ${GIT_VERSION})
message("-- Version: ${VERSION}")
# The version of the libraries
set(GENERIC_LIB_VERSION ${VERSION})
string(SUBSTRING ${VERSION} 0 1 GENERIC_LIB_SOVERSION)
# Import our CMake modules
include(CheckCXXCompilerFlag)
include(AddCXXCompilerFlag)
include(CXXFeatureCheck)
if (BENCHMARK_BUILD_32_BITS)
add_required_cxx_compiler_flag(-m32)
endif()
if ("${CMAKE_CXX_COMPILER_ID}" STREQUAL "MSVC")
# Turn compiler warnings up to 11
string(REGEX REPLACE "[-/]W[1-4]" "" CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS}")
set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} /W4")
add_definitions(-D_CRT_SECURE_NO_WARNINGS)
if (NOT BENCHMARK_ENABLE_EXCEPTIONS)
add_cxx_compiler_flag(-EHs-)
add_cxx_compiler_flag(-EHa-)
endif()
# Link time optimisation
if (BENCHMARK_ENABLE_LTO)
set(CMAKE_CXX_FLAGS_RELEASE "${CMAKE_CXX_FLAGS_RELEASE} /GL")
set(CMAKE_STATIC_LINKER_FLAGS_RELEASE "${CMAKE_STATIC_LINKER_FLAGS_RELEASE} /LTCG")
set(CMAKE_SHARED_LINKER_FLAGS_RELEASE "${CMAKE_SHARED_LINKER_FLAGS_RELEASE} /LTCG")
set(CMAKE_EXE_LINKER_FLAGS_RELEASE "${CMAKE_EXE_LINKER_FLAGS_RELEASE} /LTCG")
set(CMAKE_CXX_FLAGS_RELWITHDEBINFO "${CMAKE_CXX_FLAGS_RELWITHDEBINFO} /GL")
string(REGEX REPLACE "[-/]INCREMENTAL" "/INCREMENTAL:NO" CMAKE_STATIC_LINKER_FLAGS_RELWITHDEBINFO "${CMAKE_STATIC_LINKER_FLAGS_RELWITHDEBINFO}")
set(CMAKE_STATIC_LINKER_FLAGS_RELWITHDEBINFO "${CMAKE_STATIC_LINKER_FLAGS_RELWITHDEBINFO} /LTCG")
string(REGEX REPLACE "[-/]INCREMENTAL" "/INCREMENTAL:NO" CMAKE_SHARED_LINKER_FLAGS_RELWITHDEBINFO "${CMAKE_SHARED_LINKER_FLAGS_RELWITHDEBINFO}")
set(CMAKE_SHARED_LINKER_FLAGS_RELWITHDEBINFO "${CMAKE_SHARED_LINKER_FLAGS_RELWITHDEBINFO} /LTCG")
string(REGEX REPLACE "[-/]INCREMENTAL" "/INCREMENTAL:NO" CMAKE_EXE_LINKER_FLAGS_RELWITHDEBINFO "${CMAKE_EXE_LINKER_FLAGS_RELWITHDEBINFO}")
set(CMAKE_EXE_LINKER_FLAGS_RELWITHDEBINFO "${CMAKE_EXE_LINKER_FLAGS_RELWITHDEBINFO} /LTCG")
set(CMAKE_CXX_FLAGS_MINSIZEREL "${CMAKE_CXX_FLAGS_MINSIZEREL} /GL")
set(CMAKE_STATIC_LINKER_FLAGS_MINSIZEREL "${CMAKE_STATIC_LINKER_FLAGS_MINSIZEREL} /LTCG")
set(CMAKE_SHARED_LINKER_FLAGS_MINSIZEREL "${CMAKE_SHARED_LINKER_FLAGS_MINSIZEREL} /LTCG")
set(CMAKE_EXE_LINKER_FLAGS_MINSIZEREL "${CMAKE_EXE_LINKER_FLAGS_MINSIZEREL} /LTCG")
endif()
else()
# Try and enable C++11. Don't use C++14 because it doesn't work in some
# configurations.
add_cxx_compiler_flag(-std=c++11)
if (NOT HAVE_CXX_FLAG_STD_CXX11)
add_cxx_compiler_flag(-std=c++0x)
endif()
# Turn compiler warnings up to 11
add_cxx_compiler_flag(-Wall)
add_cxx_compiler_flag(-Wextra)
add_cxx_compiler_flag(-Wshadow)
add_cxx_compiler_flag(-Werror RELEASE)
add_cxx_compiler_flag(-Werror RELWITHDEBINFO)
add_cxx_compiler_flag(-Werror MINSIZEREL)
add_cxx_compiler_flag(-pedantic)
add_cxx_compiler_flag(-pedantic-errors)
add_cxx_compiler_flag(-Wshorten-64-to-32)
add_cxx_compiler_flag(-Wfloat-equal)
add_cxx_compiler_flag(-fstrict-aliasing)
if (NOT BENCHMARK_ENABLE_EXCEPTIONS)
add_cxx_compiler_flag(-fno-exceptions)
endif()
if (HAVE_CXX_FLAG_FSTRICT_ALIASING)
if (NOT CMAKE_CXX_COMPILER_ID STREQUAL "Intel") #ICC17u2: Many false positives for Wstrict-aliasing
add_cxx_compiler_flag(-Wstrict-aliasing)
endif()
endif()
# ICC17u2: overloaded virtual function "benchmark::Fixture::SetUp" is only partially overridden
# (because of deprecated overload)
add_cxx_compiler_flag(-wd654)
add_cxx_compiler_flag(-Wthread-safety)
if (HAVE_CXX_FLAG_WTHREAD_SAFETY)
cxx_feature_check(THREAD_SAFETY_ATTRIBUTES)
endif()
# GCC doesn't report invalid -Wno-warning flags, so check the positive
# version, and if it exists add the negative.
check_cxx_warning_flag(-Winvalid-offsetof)
if (HAVE_CXX_FLAG_WINVALID_OFFSETOF)
add_cxx_compiler_flag(-Wno-invalid-offsetof)
endif()
# On most UNIX like platforms g++ and clang++ define _GNU_SOURCE as a
# predefined macro, which turns on all of the wonderful libc extensions.
# However g++ doesn't do this in Cygwin so we have to define it ourselfs
# since we depend on GNU/POSIX/BSD extensions.
if (CYGWIN)
add_definitions(-D_GNU_SOURCE=1)
endif()
# Link time optimisation
if (BENCHMARK_ENABLE_LTO)
add_cxx_compiler_flag(-flto)
if ("${CMAKE_C_COMPILER_ID}" STREQUAL "GNU")
find_program(GCC_AR gcc-ar)
if (GCC_AR)
set(CMAKE_AR ${GCC_AR})
endif()
find_program(GCC_RANLIB gcc-ranlib)
if (GCC_RANLIB)
set(CMAKE_RANLIB ${GCC_RANLIB})
endif()
elseif("${CMAKE_C_COMPILER_ID}" STREQUAL "Clang")
include(llvm-toolchain)
endif()
endif()
# Coverage build type
set(BENCHMARK_CXX_FLAGS_COVERAGE "${CMAKE_CXX_FLAGS_DEBUG}"
CACHE STRING "Flags used by the C++ compiler during coverage builds."
FORCE)
set(BENCHMARK_EXE_LINKER_FLAGS_COVERAGE "${CMAKE_EXE_LINKER_FLAGS_DEBUG}"
CACHE STRING "Flags used for linking binaries during coverage builds."
FORCE)
set(BENCHMARK_SHARED_LINKER_FLAGS_COVERAGE "${CMAKE_SHARED_LINKER_FLAGS_DEBUG}"
CACHE STRING "Flags used by the shared libraries linker during coverage builds."
FORCE)
mark_as_advanced(
BENCHMARK_CXX_FLAGS_COVERAGE
BENCHMARK_EXE_LINKER_FLAGS_COVERAGE
BENCHMARK_SHARED_LINKER_FLAGS_COVERAGE)
set(CMAKE_BUILD_TYPE "${CMAKE_BUILD_TYPE}" CACHE STRING
"Choose the type of build, options are: None Debug Release RelWithDebInfo MinSizeRel Coverage.")
add_cxx_compiler_flag(--coverage COVERAGE)
endif()
if (BENCHMARK_USE_LIBCXX)
if ("${CMAKE_CXX_COMPILER_ID}" STREQUAL "Clang")
add_cxx_compiler_flag(-stdlib=libc++)
elseif ("${CMAKE_CXX_COMPILER_ID}" STREQUAL "GNU" OR
"${CMAKE_CXX_COMPILER_ID}" STREQUAL "Intel")
add_cxx_compiler_flag(-nostdinc++)
message("libc++ header path must be manually specified using CMAKE_CXX_FLAGS")
# Adding -nodefaultlibs directly to CMAKE_<TYPE>_LINKER_FLAGS will break
# configuration checks such as 'find_package(Threads)'
list(APPEND BENCHMARK_CXX_LINKER_FLAGS -nodefaultlibs)
# -lc++ cannot be added directly to CMAKE_<TYPE>_LINKER_FLAGS because
# linker flags appear before all linker inputs and -lc++ must appear after.
list(APPEND BENCHMARK_CXX_LIBRARIES c++)
else()
message(FATAL "-DBENCHMARK_USE_LIBCXX:BOOL=ON is not supported for compiler")
endif()
endif(BENCHMARK_USE_LIBCXX)
# C++ feature checks
# Determine the correct regular expression engine to use
cxx_feature_check(STD_REGEX)
cxx_feature_check(GNU_POSIX_REGEX)
cxx_feature_check(POSIX_REGEX)
if(NOT HAVE_STD_REGEX AND NOT HAVE_GNU_POSIX_REGEX AND NOT HAVE_POSIX_REGEX)
message(FATAL_ERROR "Failed to determine the source files for the regular expression backend")
endif()
if (NOT BENCHMARK_ENABLE_EXCEPTIONS AND HAVE_STD_REGEX
AND NOT HAVE_GNU_POSIX_REGEX AND NOT HAVE_POSIX_REGEX)
message(WARNING "Using std::regex with exceptions disabled is not fully supported")
endif()
cxx_feature_check(STEADY_CLOCK)
# Ensure we have pthreads
find_package(Threads REQUIRED)
# Set up directories
include_directories(${PROJECT_SOURCE_DIR}/include)
# Build the targets
add_subdirectory(src)
if (BENCHMARK_ENABLE_TESTING)
enable_testing()
if (BENCHMARK_ENABLE_GTEST_TESTS)
include(HandleGTest)
endif()
add_subdirectory(test)
endif()