perf: allow to provide libbenchmark for tests

This patch allows to provide the bundled libbenchmark for the
performance tests from the parent project to use non-Debug build or
whatsoever.

Needed for tarantool/tarantool#10778

Co-authored-by: Sergey Bronnikov <[email protected]>

Author: 2 people

perf/CMakeLists.txt

@@ -5,13 +5,20 @@ if (CMAKE_BUILD_TYPE STREQUAL "Debug")
     return()
 endif()
 
-find_package(benchmark QUIET)
-if (NOT ${benchmark_FOUND})
-    message(AUTHOR_WARNING "Google Benchmark submodule not found")
-    return()
+# Handle a case when BENCHMARK_LIBRARIES, BENCHMARK_INCLUDE_DIRS
+# and benchmark_FOUND are defined in the parent project, like in
+# the Tarantool, that uses the bundled Benchmark library.
+if (NOT benchmark_FOUND)
+    find_package(benchmark QUIET)
+    if (NOT benchmark_FOUND)
+        message(AUTHOR_WARNING "Google Benchmark library not found")
+        return()
+    endif()
+    set(BENCHMARK_LIBRARIES benchmark::benchmark)
 endif()
 
 include_directories("${PROJECT_SOURCE_DIR}")
 
 add_executable(small.perftest small.cc)
-target_link_libraries(small.perftest small benchmark::benchmark)
+target_link_libraries(small.perftest small ${BENCHMARK_LIBRARIES})
+target_include_directories(small.perftest PUBLIC ${BENCHMARK_INCLUDE_DIRS})