don't re-generate header file if content doesn't change (#25130)

* don't re-generate header file if content doesn't change. test=develop

* add copy_if_different function. test=develop

.gitignore

@@ -10,6 +10,7 @@ paddle/fluid/op_use_default_grad_maker_PR.spec
 build/
 build_doc/
 *.user
+*.tmp
 
 .vscode
 .idea

CMakeLists.txt

@@ -30,7 +30,7 @@ option(WITH_GPU         "Compile PaddlePaddle with NVIDIA GPU"          ${CUDA_F
 
 # cmake 3.12, 3.13, 3.14 will append gcc link options to nvcc, and nvcc doesn't recognize them.
 if(WITH_GPU AND (${CMAKE_VERSION} VERSION_GREATER_EQUAL 3.12) AND (${CMAKE_VERSION} VERSION_LESS 3.15))
-    message(FATAL_ERROR "cmake ${CMAKE_VERSION} is not supported when WITH_GPU=ON because of bug https://tinyurl.com/ydbb9m7n. "
+    message(FATAL_ERROR "cmake ${CMAKE_VERSION} is not supported when WITH_GPU=ON because of bug https://cmake.org/pipermail/cmake/2018-September/068195.html. "
        "You can use cmake 3.16 (recommended), 3.10, 3.11, 3.15 or 3.17. Please refer to the install document: https://cmake.org/install/")
 endif()
 

cmake/generic.cmake

@@ -820,3 +820,19 @@ function(brpc_library TARGET_NAME)
   cc_library("${TARGET_NAME}_proto" SRCS "${brpc_proto_srcs}")
   cc_library("${TARGET_NAME}" SRCS "${brpc_library_SRCS}" DEPS "${TARGET_NAME}_proto" "${brpc_library_DEPS}")
 endfunction()
+
+# copy_if_different from src_file to dst_file before barrier_target.
+function(copy_if_different src_file dst_file barrier_target)
+  # this is a dummy target, should always be run to update ${pybind_file_final}
+  add_custom_target(before_${barrier_target} ALL
+      DEPENDS before_${barrier_target}_custom_command
+  )
+  add_dependencies(${barrier_target} before_${barrier_target})
+
+  add_custom_command(
+      OUTPUT before_${barrier_target}_custom_command
+      COMMAND ${CMAKE_COMMAND} -E copy_if_different ${src_file} ${dst_file}
+      COMMENT "copy_if_different ${dst_file}"
+      VERBATIM
+  )
+endfunction()

paddle/fluid/framework/ir/CMakeLists.txt

-set(pass_file ${PADDLE_BINARY_DIR}/paddle/fluid/inference/api/paddle_inference_pass.h)
+set(pass_file ${PADDLE_BINARY_DIR}/paddle/fluid/inference/api/paddle_inference_pass.h.tmp)
+set(pass_file_final ${PADDLE_BINARY_DIR}/paddle/fluid/inference/api/paddle_inference_pass.h)
 file(WRITE ${pass_file} "// Generated by the paddle/fluid/framework/ir/CMakeLists.txt.  DO NOT EDIT!\n\n")
 file(APPEND ${pass_file} "\#pragma once\n")
 file(APPEND ${pass_file} "\#include \"paddle/fluid/framework/ir/pass.h\"\n")
 
+copy_if_different(${pass_file} ${pass_file_final} extern_glog)
+
 add_subdirectory(fuse_optimizer_ops_pass)
 add_subdirectory(memory_optimize_pass)
 add_subdirectory(multi_devices_graph_pass)

paddle/fluid/inference/analysis/ir_passes/CMakeLists.txt

@@ -7,7 +7,7 @@ if (WITH_GPU AND TENSORRT_FOUND)
           subgraph_util tensorrt_subgraph_pass
           CACHE INTERNAL "")
 
-  set(pass_file ${PADDLE_BINARY_DIR}/paddle/fluid/inference/api/paddle_inference_pass.h)
+  set(pass_file ${PADDLE_BINARY_DIR}/paddle/fluid/inference/api/paddle_inference_pass.h.tmp)
   file(APPEND ${pass_file} "USE_PASS(tensorrt_subgraph_pass);\n")
   set(INFER_IR_PASSES ${INFER_IR_PASSES} tensorrt_subgraph_pass CACHE INTERNAL "")
 endif()
@@ -15,7 +15,7 @@ endif()
 if (WITH_LITE) 
   cc_library(lite_subgraph_pass SRCS lite_subgraph_pass.cc DEPS ${analysis_deps} subgraph_util lite_op_teller)
   set(analysis_deps ${analysis_deps} subgraph_util lite_subgraph_pass CACHE INTERNAL "")
-  set(pass_file ${PADDLE_BINARY_DIR}/paddle/fluid/inference/api/paddle_inference_pass.h)
+  set(pass_file ${PADDLE_BINARY_DIR}/paddle/fluid/inference/api/paddle_inference_pass.h.tmp)
   file(APPEND ${pass_file} "USE_PASS(lite_subgraph_pass);\n")
   set(INFER_IR_PASSES ${INFER_IR_PASSES} lite_subgraph_pass CACHE INTERNAL "")
   cc_test(lite_subgraph_pass_tester SRCS lite_subgraph_pass_tester.cc DEPS lite_subgraph_pass gtest glog)

paddle/fluid/operators/CMakeLists.txt

@@ -3,8 +3,11 @@ include(operators)
 # clean cache and pybind_file content first when rebuild
 unset(GLOB_OP_LIB CACHE)
 unset(OP_LIBRARY CACHE)
-set(pybind_file ${PADDLE_BINARY_DIR}/paddle/fluid/pybind/pybind.h CACHE INTERNAL "pybind.h file")
-file(WRITE ${pybind_file} "// Generated by the paddle/fluid/operator/CMakeLists.txt.  DO NOT EDIT!\n\n")
+set(pybind_file ${PADDLE_BINARY_DIR}/paddle/fluid/pybind/pybind.h.tmp CACHE INTERNAL "pybind.h file")
+set(pybind_file_final ${PADDLE_BINARY_DIR}/paddle/fluid/pybind/pybind.h)
+file(WRITE ${pybind_file} "// Generated by the paddle/fluid/operators/CMakeLists.txt.  DO NOT EDIT!\n\n")
+
+copy_if_different(${pybind_file} ${pybind_file_final} operator)
 
 add_subdirectory(math)
 add_subdirectory(controlflow)

paddle/fluid/operators/jit/CMakeLists.txt

 
-set(jit_file ${PADDLE_BINARY_DIR}/paddle/fluid/operators/jit/kernels.h)
+set(jit_file ${PADDLE_BINARY_DIR}/paddle/fluid/operators/jit/kernels.h.tmp)
+set(jit_file_final ${PADDLE_BINARY_DIR}/paddle/fluid/operators/jit/kernels.h)
 file(WRITE  ${jit_file} "// Generated by the paddle/fluid/operators/jit/CMakeLists.txt.  DO NOT EDIT!\n\n")
 file(APPEND ${jit_file} "\#pragma once\n")
 file(APPEND ${jit_file} "\#include \"paddle/fluid/operators/jit/helper.h\"\n")
@@ -11,6 +12,8 @@ file(GLOB jit_kernel_cc_srcs RELATIVE "${CMAKE_CURRENT_SOURCE_DIR}" "*.cc")
 list(REMOVE_ITEM jit_kernel_cc_srcs test.cc benchmark.cc)
 cc_library(jit_kernel_base SRCS ${jit_kernel_cc_srcs} DEPS ${JIT_KERNEL_DEPS})
 
+copy_if_different(${jit_file} ${jit_file_final} jit_kernel_base)
+
 # refer must go first
 add_subdirectory(refer)
 add_subdirectory(more)

paddle/fluid/pybind/CMakeLists.txt

@@ -66,23 +66,34 @@ if(WITH_PYTHON)
   get_property (os_dependency_modules GLOBAL PROPERTY OS_DEPENDENCY_MODULES)
   target_link_libraries(op_function_generator ${os_dependency_modules})
 
+  set(impl_file ${CMAKE_SOURCE_DIR}/paddle/fluid/pybind/op_function_impl.h)
+  set(tmp_impl_file ${impl_file}.tmp)
+
   if(WIN32)
-    add_custom_target(op_function_cmd 
+    add_custom_command(TARGET op_function_generator
+          POST_BUILD
           COMMAND "${CMAKE_BINARY_DIR}/paddle/fluid/pybind/${CMAKE_BUILD_TYPE}/op_function_generator"
-              "${CMAKE_SOURCE_DIR}/paddle/fluid/pybind/op_function_impl.h") 
-    add_dependencies(op_function_cmd op_function_generator)
+              "${tmp_impl_file}"
+          COMMAND ${CMAKE_COMMAND} -E copy_if_different ${tmp_impl_file} ${impl_file}
+          COMMENT "copy_if_different ${impl_file}"
+          VERBATIM
+    )
+
     if(${CBLAS_PROVIDER} STREQUAL MKLML)
-      add_custom_command(TARGET op_function_generator POST_BUILD
+      add_custom_command(TARGET op_function_generator
+            PRE_BUILD
             COMMAND ${CMAKE_COMMAND} -E copy ${MKLML_SHARED_LIB} ${CMAKE_CURRENT_BINARY_DIR}/${CMAKE_BUILD_TYPE}
             COMMAND ${CMAKE_COMMAND} -E copy ${MKLML_SHARED_IOMP_LIB} ${CMAKE_CURRENT_BINARY_DIR}/${CMAKE_BUILD_TYPE}
           )
     else(${CBLAS_PROVIDER} STREQUAL EXTERN_OPENBLAS)
-      add_custom_command(TARGET op_function_generator POST_BUILD 
+      add_custom_command(TARGET op_function_generator
+            PRE_BUILD
             COMMAND ${CMAKE_COMMAND} -E copy ${OPENBLAS_SHARED_LIB} ${CMAKE_CURRENT_BINARY_DIR}/${CMAKE_BUILD_TYPE}
           )
     endif()
     if(WITH_MKLDNN)
-      add_custom_command(TARGET op_function_generator POST_BUILD 
+      add_custom_command(TARGET op_function_generator
+          PRE_BUILD
           COMMAND ${CMAKE_COMMAND} -E copy ${MKLDNN_SHARED_LIB} ${CMAKE_CURRENT_BINARY_DIR}/${CMAKE_BUILD_TYPE}
           )
     endif()
@@ -91,19 +102,25 @@ if(WITH_PYTHON)
     # copy these *.so to current directory and append current directory to
     # LD_LIBRARY_PATH. This is different with Windows platformm, which search 
     # *.dll in current directory automatically.
-    add_custom_target(op_function_cmd 
+    add_custom_command(TARGET op_function_generator
+          POST_BUILD
           COMMAND ${CMAKE_COMMAND} -E env "LD_LIBRARY_PATH=$ENV{LD_LIBRARY_PATH}:."
               "${CMAKE_CURRENT_BINARY_DIR}/op_function_generator"
-              "${CMAKE_SOURCE_DIR}/paddle/fluid/pybind/op_function_impl.h") 
-    add_dependencies(op_function_cmd op_function_generator)
+              "${tmp_impl_file}"
+          COMMAND ${CMAKE_COMMAND} -E copy_if_different ${tmp_impl_file} ${impl_file}
+          COMMENT "copy_if_different ${impl_file}"
+          VERBATIM
+    )
     if(WITH_MKL)
-      add_custom_command(TARGET op_function_generator POST_BUILD 
+      add_custom_command(TARGET op_function_generator
+            PRE_BUILD
             COMMAND ${CMAKE_COMMAND} -E copy ${MKLML_SHARED_LIB} ${CMAKE_CURRENT_BINARY_DIR}
             COMMAND ${CMAKE_COMMAND} -E copy ${MKLML_SHARED_IOMP_LIB} ${CMAKE_CURRENT_BINARY_DIR}
             )
     endif(WITH_MKL)
     if(WITH_MKLDNN)
-      add_custom_command(TARGET op_function_generator POST_BUILD 
+      add_custom_command(TARGET op_function_generator
+          PRE_BUILD
           COMMAND ${CMAKE_COMMAND} -E copy ${MKLDNN_SHARED_LIB} ${CMAKE_CURRENT_BINARY_DIR}
           )
     endif(WITH_MKLDNN)
@@ -126,5 +143,5 @@ if(WITH_PYTHON)
 
   get_property (os_dependency_modules GLOBAL PROPERTY OS_DEPENDENCY_MODULES)
   target_link_libraries(paddle_pybind ${os_dependency_modules})
-  add_dependencies(paddle_pybind op_function_cmd)
+  add_dependencies(paddle_pybind op_function_generator)
 endif(WITH_PYTHON)