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| author | Simon Pilgrim <llvm-dev@redking.me.uk> | 2019-10-01 13:39:43 +0000 |
|---|---|---|
| committer | Simon Pilgrim <llvm-dev@redking.me.uk> | 2019-10-01 13:39:43 +0000 |
| commit | 9eb2bd6b8d6d31cee53f4f89dd9189da721ed4a8 (patch) | |
| tree | a822243583ece7fc0348c7bb75066dd685d2c234 /llvm/cmake | |
| parent | e4e305e5eea536fb9d9dc64f612b164822d4bf34 (diff) | |
| download | bcm5719-llvm-9eb2bd6b8d6d31cee53f4f89dd9189da721ed4a8.tar.gz bcm5719-llvm-9eb2bd6b8d6d31cee53f4f89dd9189da721ed4a8.zip | |
Revert rL349624 : Let TableGen write output only if it changed, instead of doing so in cmake, attempt 2
Differential Revision: https://reviews.llvm.org/D55842
-----------------
As discussed on PR43385 this is causing Visual Studio msbuilds to perpetually rebuild all tablegen generated files
llvm-svn: 373338
Diffstat (limited to 'llvm/cmake')
| -rw-r--r-- | llvm/cmake/modules/TableGen.cmake | 20 |
1 files changed, 16 insertions, 4 deletions
diff --git a/llvm/cmake/modules/TableGen.cmake b/llvm/cmake/modules/TableGen.cmake index ca9357e295e..71dfebb12b4 100644 --- a/llvm/cmake/modules/TableGen.cmake +++ b/llvm/cmake/modules/TableGen.cmake @@ -23,7 +23,7 @@ function(tablegen project ofn) file(RELATIVE_PATH ofn_rel ${CMAKE_BINARY_DIR} ${CMAKE_CURRENT_BINARY_DIR}/${ofn}) set(additional_cmdline - -o ${ofn_rel} + -o ${ofn_rel}.tmp -d ${ofn_rel}.d WORKING_DIRECTORY ${CMAKE_BINARY_DIR} DEPFILE ${CMAKE_CURRENT_BINARY_DIR}/${ofn}.d @@ -34,7 +34,7 @@ function(tablegen project ofn) file(GLOB local_tds "*.td") file(GLOB_RECURSE global_tds "${LLVM_MAIN_INCLUDE_DIR}/llvm/*.td") set(additional_cmdline - -o ${CMAKE_CURRENT_BINARY_DIR}/${ofn} + -o ${CMAKE_CURRENT_BINARY_DIR}/${ofn}.tmp ) endif() @@ -67,7 +67,8 @@ function(tablegen project ofn) # dependency twice in the result file when # ("${${project}_TABLEGEN_TARGET}" STREQUAL "${${project}_TABLEGEN_EXE}") # but lets us having smaller and cleaner code here. - add_custom_command(OUTPUT ${CMAKE_CURRENT_BINARY_DIR}/${ofn} + add_custom_command(OUTPUT ${CMAKE_CURRENT_BINARY_DIR}/${ofn}.tmp + # Generate tablegen output in a temporary file. COMMAND ${${project}_TABLEGEN_EXE} ${ARGN} -I ${CMAKE_CURRENT_SOURCE_DIR} ${LLVM_TABLEGEN_FLAGS} ${LLVM_TARGET_DEFINITIONS_ABSOLUTE} @@ -80,9 +81,20 @@ function(tablegen project ofn) ${LLVM_TARGET_DEFINITIONS_ABSOLUTE} COMMENT "Building ${ofn}..." ) + add_custom_command(OUTPUT ${CMAKE_CURRENT_BINARY_DIR}/${ofn} + # Only update the real output file if there are any differences. + # This prevents recompilation of all the files depending on it if there + # aren't any. + COMMAND ${CMAKE_COMMAND} -E copy_if_different + ${CMAKE_CURRENT_BINARY_DIR}/${ofn}.tmp + ${CMAKE_CURRENT_BINARY_DIR}/${ofn} + DEPENDS ${CMAKE_CURRENT_BINARY_DIR}/${ofn}.tmp + COMMENT "Updating ${ofn}..." + ) # `make clean' must remove all those generated files: - set_property(DIRECTORY APPEND PROPERTY ADDITIONAL_MAKE_CLEAN_FILES ${ofn}) + set_property(DIRECTORY APPEND + PROPERTY ADDITIONAL_MAKE_CLEAN_FILES ${ofn}.tmp ${ofn}) set(TABLEGEN_OUTPUT ${TABLEGEN_OUTPUT} ${CMAKE_CURRENT_BINARY_DIR}/${ofn} PARENT_SCOPE) set_source_files_properties(${CMAKE_CURRENT_BINARY_DIR}/${ofn} PROPERTIES |
