Reland: [Offload] Don't check in generated files (llvm#141982) (llvm#2572)

Author: ronlieb

offload/CMakeLists.txt

@@ -447,6 +447,8 @@ if(OFFLOAD_ENABLE_EMISSARY_APIS)
     DESTINATION ${LIBOMP_HEADERS_INSTALL_PATH})
 endif()
 
+add_subdirectory(tools/offload-tblgen)
+
 # Build offloading plugins and device RTLs if they are available.
 add_subdirectory(plugins-nextgen)
 
@@ -457,7 +459,6 @@ add_subdirectory(DeviceRTL)
 add_subdirectory(libomptarget)
 
 # FIXME: Re-enable once OMPT design allows
-# add_subdirectory(tools/offload-tblgen)
 # add_subdirectory(liboffload)
 
 # Add tests.

offload/include/Shared/OffloadErrcodes.inc

@@ -1,27 +1,40 @@
-# The OffloadGenerate target is used to regenerate the generated files in the
-# include directory. These files are checked in with the rest of the source,
-# therefore it is only needed when making changes to the API.
+# We want to clang-format the generated files if possible, since OffloadAPI.h is
+# the main public header for liboffload. Generate them in a temporary location,
+# then clang-format and copy them to the proper location. If clang-format is
+# missing just copy them.
+# Ideally we'd just clang-format them in place and avoid the copy but cmake
+# gets confused about the same path being a byproduct of two custom commands.
 
-find_program(CLANG_FORMAT clang-format PATHS ${LLVM_TOOLS_BINARY_DIR} NO_DEFAULT_PATH)
-if (CLANG_FORMAT)
-    set(LLVM_TARGET_DEFINITIONS ${CMAKE_CURRENT_SOURCE_DIR}/OffloadAPI.td)
+set(LLVM_TARGET_DEFINITIONS ${CMAKE_CURRENT_SOURCE_DIR}/OffloadAPI.td)
+set(files_to_copy "")
+file(MAKE_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR}/generated)
 
-    tablegen(OFFLOAD OffloadAPI.h -gen-api)
-    tablegen(OFFLOAD OffloadEntryPoints.inc -gen-entry-points)
-    tablegen(OFFLOAD OffloadFuncs.inc -gen-func-names)
-    tablegen(OFFLOAD OffloadImplFuncDecls.inc -gen-impl-func-decls)
-    tablegen(OFFLOAD OffloadPrint.hpp -gen-print-header)
-    tablegen(OFFLOAD OffloadErrcodes.inc -gen-errcodes)
+macro(offload_tablegen file)
+    tablegen(OFFLOAD generated/${file}.gen ${ARGN})
+    list(APPEND files_to_copy ${file})
+endmacro()
 
-    set(FILES_TO_COPY "OffloadAPI.h;OffloadEntryPoints.inc;OffloadFuncs.inc;OffloadImplFuncDecls.inc;OffloadPrint.hpp")
-    set(GEN_DIR ${CMAKE_CURRENT_SOURCE_DIR}/../include/generated)
-    add_public_tablegen_target(OffloadGenerate)
-    add_custom_command(TARGET OffloadGenerate POST_BUILD COMMAND ${CLANG_FORMAT}
-        -i ${TABLEGEN_OUTPUT})
-    add_custom_command(TARGET OffloadGenerate POST_BUILD COMMAND ${CMAKE_COMMAND}
-        -E copy_if_different ${FILES_TO_COPY} ${GEN_DIR})
-    add_custom_command(TARGET OffloadGenerate POST_BUILD COMMAND ${CMAKE_COMMAND}
-        -E copy_if_different OffloadErrcodes.inc "${LIBOMPTARGET_INCLUDE_DIR}/Shared/OffloadErrcodes.inc")
+offload_tablegen(OffloadAPI.h -gen-api)
+offload_tablegen(OffloadEntryPoints.inc -gen-entry-points)
+offload_tablegen(OffloadFuncs.inc -gen-func-names)
+offload_tablegen(OffloadImplFuncDecls.inc -gen-impl-func-decls)
+offload_tablegen(OffloadPrint.hpp -gen-print-header)
+
+add_public_tablegen_target(OffloadGenerate)
+
+add_custom_target(OffloadAPI DEPENDS OffloadGenerate)
+find_program(clang_format clang-format PATHS ${LLVM_TOOLS_BINARY_DIR} NO_DEFAULT_PATH)
+if (clang_format)
+    foreach(file IN LISTS files_to_copy)
+      add_custom_command(
+          OUTPUT ${file}
+          COMMAND ${clang_format} -i generated/${file}.gen
+          COMMAND ${CMAKE_COMMAND} -E copy_if_different generated/${file}.gen ${CMAKE_CURRENT_BINARY_DIR}/${file}
+          DEPENDS generated/${file}.gen
+      )
+      add_custom_target(OffloadAPI.${file} DEPENDS ${file})
+      add_dependencies(OffloadAPI OffloadAPI.${file})
+    endforeach()
 else()
     message(WARNING "clang-format not found, the generated Offload API headers will not be formatted")
     foreach(file IN LISTS files_to_copy)

offload/liboffload/API/CMakeLists.txt

@@ -8,6 +8,10 @@ add_llvm_library(
   LINK_COMPONENTS
   FrontendOpenMP
   Support
+
+  DEPENDS
+  OffloadAPI
+  PluginErrcodes
   )
 
 foreach(plugin IN LISTS LIBOMPTARGET_PLUGINS_TO_BUILD)
@@ -19,11 +23,13 @@ if(LIBOMP_HAVE_VERSION_SCRIPT_FLAG)
 endif()
 
 target_include_directories(LLVMOffload PUBLIC
+                            ${CMAKE_CURRENT_BINARY_DIR}/API
                             ${CMAKE_CURRENT_BINARY_DIR}/../include
                             ${CMAKE_CURRENT_SOURCE_DIR}/include
-                            ${CMAKE_CURRENT_SOURCE_DIR}/include/generated
                             ${CMAKE_CURRENT_SOURCE_DIR}/../include
-                            ${CMAKE_CURRENT_SOURCE_DIR}/../plugins-nextgen/common/include)
+                            ${CMAKE_CURRENT_SOURCE_DIR}/../plugins-nextgen/common/include
+                            ${CMAKE_CURRENT_BINARY_DIR}/../plugins-nextgen/common/include
+                            )
 
 target_compile_options(LLVMOffload PRIVATE ${offload_compile_flags})
 target_link_options(LLVMOffload PRIVATE ${offload_link_flags})
@@ -39,5 +45,5 @@ set_target_properties(LLVMOffload PROPERTIES
                       BUILD_RPATH "$ORIGIN:${CMAKE_CURRENT_BINARY_DIR}/..")
 install(TARGETS LLVMOffload LIBRARY COMPONENT LLVMOffload DESTINATION "${OFFLOAD_INSTALL_LIBDIR}")
 
-install(FILES ${CMAKE_CURRENT_SOURCE_DIR}/include/generated/OffloadAPI.h DESTINATION ${CMAKE_INSTALL_PREFIX}/include/offload)
-install(FILES ${CMAKE_CURRENT_SOURCE_DIR}/include/generated/OffloadPrint.hpp DESTINATION ${CMAKE_INSTALL_PREFIX}/include/offload)
+install(FILES ${CMAKE_CURRENT_BINARY_DIR}/API/OffloadAPI.h DESTINATION ${CMAKE_INSTALL_PREFIX}/include/offload)
+install(FILES ${CMAKE_CURRENT_BINARY_DIR}/API/OffloadPrint.hpp DESTINATION ${CMAKE_INSTALL_PREFIX}/include/offload)