Revert "[CMake] Improve the clang order-file generation workflow"

This reverts commit r259862, and attempts to fix builder CMakeCaches.

Will try this again some other time...

Conflicts:

	CMakeLists.txt
	tools/driver/CMakeLists.txt

llvm-svn: 259872

3 files changed, 6 insertions, 19 deletions

diff --git a/clang/CMakeLists.txt b/clang/CMakeLists.txt
index bdd0ec91240..ca2305e3069 100644
--- a/clang/CMakeLists.txt
+++ b/clang/CMakeLists.txt
@@ -586,24 +586,14 @@ if( CLANG_INCLUDE_DOCS )
   add_subdirectory(docs)
 endif()
 
-# this line is needed as a cleanup to ensure that any CMakeCaches with the old
-# default value get updated to the new default.
-if(CLANG_ORDER_FILE STREQUAL "")
+if(CLANG_ORDER_FILE STREQUAL "${CMAKE_CURRENT_BINARY_DIR}/clang.order")
   unset(CLANG_ORDER_FILE CACHE)
+  unset(CLANG_ORDER_FILE)
 endif()
 
-set(CLANG_ORDER_FILE ${CMAKE_CURRENT_BINARY_DIR}/clang.order CACHE FILEPATH
+set(CLANG_ORDER_FILE "" CACHE FILEPATH
   "Order file to use when compiling clang in order to improve startup time.")
 
-file(READ ${CLANG_ORDER_FILE} order_file 20)
-if(order_file STREQUAL "")
-  file(REMOVE ${CLANG_ORDER_FILE})
-endif()
-
-if(CLANG_ORDER_FILE AND NOT EXISTS ${CLANG_ORDER_FILE})
-  file(WRITE ${CLANG_ORDER_FILE} "\n")
-endif()
-
 if (CLANG_BUILT_STANDALONE OR CMAKE_VERSION VERSION_EQUAL 3 OR
     CMAKE_VERSION VERSION_GREATER 3)
   # Generate a list of CMake library targets so that other CMake projects can
diff --git a/clang/tools/driver/CMakeLists.txt b/clang/tools/driver/CMakeLists.txt
index c6818af5ae1..ffcfbb505ae 100644
--- a/clang/tools/driver/CMakeLists.txt
+++ b/clang/tools/driver/CMakeLists.txt
@@ -87,12 +87,8 @@ if (APPLE)
   set(TOOL_INFO_BUILD_VERSION)
 endif()
 
-check_cxx_compiler_flag("-Wl,-order_file,${CLANG_ORDER_FILE}"
-  LINKER_HAS_ORDER_FILE_FLAG)
-
-if(LINKER_HAS_ORDER_FILE_FLAG AND CLANG_ORDER_FILE)
+if(CLANG_ORDER_FILE)
   target_link_libraries(clang "-Wl,-order_file,${CLANG_ORDER_FILE}")
-  set_target_properties(clang PROPERTIES LINK_DEPENDS ${CLANG_ORDER_FILE})
 endif()
 
 if(WITH_POLLY AND LINK_POLLY_INTO_TOOLS)
diff --git a/clang/utils/perf-training/CMakeLists.txt b/clang/utils/perf-training/CMakeLists.txt
index f8647a0e44f..32f7c84555b 100644
--- a/clang/utils/perf-training/CMakeLists.txt
+++ b/clang/utils/perf-training/CMakeLists.txt
@@ -55,8 +55,9 @@ if(DTRACE)
     COMMAND ${PYTHON_EXECUTABLE} ${CMAKE_CURRENT_SOURCE_DIR}/perf-helper.py clean ${CMAKE_CURRENT_BINARY_DIR} dtrace
     COMMENT "Clearing old dtrace data")
 
+
   add_custom_target(generate-order-file
-    COMMAND ${PYTHON_EXECUTABLE} ${CMAKE_CURRENT_SOURCE_DIR}/perf-helper.py gen-order-file --binary $<TARGET_FILE:clang> --output ${CLANG_ORDER_FILE} ${CMAKE_CURRENT_BINARY_DIR}
+    COMMAND ${PYTHON_EXECUTABLE} ${CMAKE_CURRENT_SOURCE_DIR}/perf-helper.py gen-order-file --binary $<TARGET_FILE:clang> --output ${CMAKE_CURRENT_BINARY_DIR}/clang.order ${CMAKE_CURRENT_BINARY_DIR}
     COMMENT "Generating order file"
     DEPENDS generate-dtrace-logs)
 endif()