Add benchmark

* add benchmark option
* updated changelog
* added benchmark info to readme
* add bench folder to format.py

bench/CMakeLists.txt

@@ -0,0 +1,50 @@
+# This project is licensed under the MIT license. For more information see the
+# LICENSE file.
+
+if (UNIX AND NOT APPLE)
+  execute_process(COMMAND ${CMAKE_CXX_COMPILER}
+                  -fuse-ld=gold -Wl,--version
+                  ERROR_QUIET OUTPUT_VARIABLE ld_version)
+  if ("${ld_version}" MATCHES "GNU gold")
+    message(STATUS "Found Gold linker, use faster linker")
+    set(CMAKE_EXE_LINKER_FLAGS
+        "${CMAKE_EXE_LINKER_FLAGS} -fuse-ld=gold")
+    set(CMAKE_SHARED_LINKER_FLAGS
+        "${CMAKE_SHARED_LINKER_FLAGS} -fuse-ld=gold ")
+  endif()
+endif()
+
+# ------------------------------------------------------------------------------
+
+include(FetchContent)
+
+FetchContent_Declare(
+  nanobench
+  GIT_REPOSITORY https://github.com/martinus/nanobench.git
+  GIT_TAG v4.3.11
+  GIT_SHALLOW TRUE
+)
+
+FetchContent_MakeAvailable(nanobench)
+
+# ------------------------------------------------------------------------------
+
+file(GLOB_RECURSE MADDY_BENCHMARK_FILES
+  ${CMAKE_CURRENT_SOURCE_DIR}/main.cpp
+)
+
+# ------------------------------------------------------------------------------
+
+add_executable(
+  maddy_benchmark
+    ${MADDY_BENCHMARK_FILES}
+    ${CMAKE_CURRENT_SOURCE_DIR}/main.cpp
+)
+target_include_directories(maddy_benchmark PUBLIC
+  ${CMAKE_CURRENT_SOURCE_DIR}
+)
+target_link_libraries(maddy_benchmark maddy nanobench::nanobench)
+set_target_properties(maddy_benchmark PROPERTIES
+  CMAKE_CXX_FLAGS
+  "${CMAKE_CXX_FLAGS} -O2 -Wall -Wno-ignored-qualifiers -Wpedantic -Wextra -Wno-deprecated -fno-exceptions -fno-rtti"
+)