CMake: add DART_USE_SYSTEM_GOOGLEBENCHMARK (#1904)

CMakeLists.txt

@@ -99,6 +99,7 @@ dart_option(DART_FAST_DEBUG "Add -O1 option for DEBUG mode build" OFF)
 dart_option(DART_FORCE_COLORED_OUTPUT
   "Always produce ANSI-colored output (GNU/Clang only)." OFF)
 dart_option(DART_USE_SYSTEM_IMGUI "Use system ImGui" OFF)
+dart_option(DART_USE_SYSTEM_GOOGLEBENCHMARK "Use system GoogleBenchmark" OFF)
 dart_option(DART_USE_SYSTEM_GOOGLETEST "Use system GoogleTest" OFF)
 
 #===============================================================================
@@ -259,7 +260,7 @@ if(MSVC)
 
 elseif(CMAKE_COMPILER_IS_GNUCXX)
 
-  # There is a known bug in GCC 12.1 and above that leads to spurious 
+  # There is a known bug in GCC 12.1 and above that leads to spurious
   # -Wmaybe-uninitialized warnings from gcc/x86_64-linux-gnu/12/include/avxintrin.h and
   # -Warray-bounds warnings from gcc/x86_64-linux-gnu/12/include/avx512fintrin.h.
   # The bug is tracked here: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105593

tests/benchmark/CMakeLists.txt

@@ -28,14 +28,18 @@
 #   ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 #   POSSIBILITY OF SUCH DAMAGE.
 
-include(FetchContent)
-FetchContent_Declare(
-  benchmark
-  GIT_REPOSITORY https://github.com/google/benchmark.git
-  GIT_TAG v1.8.3
-)
-set(BENCHMARK_ENABLE_TESTING OFF CACHE BOOL "" FORCE)
-FetchContent_MakeAvailable(benchmark)
+if(DART_USE_SYSTEM_GOOGLEBENCHMARK)
+  find_package(benchmark REQUIRED)
+else()
+  include(FetchContent)
+  FetchContent_Declare(
+    benchmark
+    GIT_REPOSITORY https://github.com/google/benchmark.git
+    GIT_TAG v1.8.3
+  )
+  set(BENCHMARK_ENABLE_TESTING OFF CACHE BOOL "" FORCE)
+  FetchContent_MakeAvailable(benchmark)
+endif()
 
 add_subdirectory(unit)
 add_subdirectory(integration)