add flagcx as submodule and build it during cmake

Author: mikethegoblin

.gitmodules

@@ -129,3 +129,7 @@
 	path = third_party/openvino
 	url = https://github.com/openvinotoolkit/openvino.git
 	ignore = dirty
+[submodule "third_party/flagcx"]
+	path = third_party/flagcx
+	url = https://github.com/FlagOpen/FlagCX.git
+	ignore = dirty

CMakeLists.txt

@@ -541,7 +541,7 @@ endif()
 
 if(WITH_FLAGCX)
   add_definitions("-DPADDLE_WITH_FLAGCX")
-  include(flagcx)
+  # include(flagcx)
 endif()
 
 if(WITH_HETERPS AND WITH_PSLIB)

cmake/external/flagcx.cmake

@@ -0,0 +1,50 @@
+set(CMAKE_FIND_DEBUG_MODE ON)
+# flagcx.cmake
+if(NOT WITH_FLAGCX)
+  return()
+endif()
+
+set(FLAGCX_SOURCE_DIR "${PADDLE_SOURCE_DIR}/third_party/flagcx")
+set(FLAGCX_BINARY_DIR "${PADDLE_SOURCE_DIR}/build/third_party/flagcx")
+# set(FLAGCX_INCLUDE_DIR "${THIRD_PARTY_PATH}/flagcx/flagcx/include")
+set(FLAGCX_LIB_DIR "${PADDLE_SOURCE_DIR}/build/third_party/flagcx/build/lib")
+
+message(STATUS "Copying third-party source to build directory")
+execute_process(
+    COMMAND ${CMAKE_COMMAND} -E remove_directory ${FLAGCX_BINARY_DIR}
+    COMMAND ${CMAKE_COMMAND} -E copy_directory ${FLAGCX_SOURCE_DIR} ${FLAGCX_BINARY_DIR}
+    RESULT_VARIABLE COPY_RESULT
+)
+
+if(NOT COPY_RESULT EQUAL 0)
+    message(FATAL_ERROR "Failed to copy third-party source to build directory")
+endif()
+
+# Create a custom target to build the third-party library
+message(STATUS "Building third-party library with its Makefile")
+execute_process(
+    COMMAND make 
+    WORKING_DIRECTORY ${FLAGCX_BINARY_DIR}
+    RESULT_VARIABLE BUILD_RESULT
+)
+
+if(NOT BUILD_RESULT EQUAL 0)
+    message(FATAL_ERROR "Failed to build third-party library")
+endif()
+
+# set(FLAGCX_ROOT
+#       $ENV{FLAGCX_ROOT}
+#       CACHE PATH "FLAGCX_ROOT")
+#   message(STATUS "FLAGCX_ROOT is ${FLAGCX_ROOT}")
+  generate_dummy_static_lib(LIB_NAME "flagcx" GENERATOR "flagcx.cmake")
+  find_path(
+    FLAGCX_INCLUDE_DIR flagcx.h
+    PATHS ${FLAGCX_SOURCE_DIR}/flagcx/include
+    NO_DEFAULT_PATH)
+  message(STATUS "FLAGCX_INCLUDE_DIR is ${FLAGCX_INCLUDE_DIR}")
+  include_directories(SYSTEM ${FLAGCX_INCLUDE_DIR})
+  set(FLAGCX_LIB
+      "${FLAGCX_LIB_DIR}/libflagcx.so"
+      CACHE FILEPATH "flagcx library." FORCE)
+  target_link_libraries(flagcx ${FLAGCX_LIB})
+  message(STATUS "FLAGCX_LIB is ${FLAGCX_LIB}")

cmake/flagcx.cmake

@@ -469,6 +469,10 @@ if(WITH_TESTING OR WITH_DISTRIBUTE)
   include(external/gtest) # download, build, install gtest
   list(APPEND third_party_deps extern_gtest)
 endif()
+if (WITH_FLAGCX)
+  include(external/flagcx)
+  list(APPEND third_party_deps flagcx)
+endif()
 
 if(WITH_ONNXRUNTIME)
   include(external/onnxruntime