[cmake] Some NFC changes in preparation for accomodating `Ninja Multi-Config`

[akyrtzi]

Summary

• Use MATCHES so that Ninja Multi-Config generator also satisfies the Ninja check
• Pull out a couple of values into variables, inside function(tablegen project ofn), NFC

[dexonsmith]

LGTM.

llvm/cmake/config-ix.cmake

else()
     endif()
   endif()
 endif()
 
 find_program(GOLD_EXECUTABLE NAMES ${LLVM_DEFAULT_TARGET_TRIPLE}-ld.gold ld.gold ${LLVM_DEFAULT_TARGET_TRIPLE}-ld ld DOC "The gold linker")
 set(LLVM_BINUTILS_INCDIR "" CACHE PATH
     "PATH to binutils/include containing plugin-api.h for gold plugin.")
 
-if(CMAKE_GENERATOR STREQUAL "Ninja")
+if(CMAKE_GENERATOR MATCHES "Ninja")
   execute_process(COMMAND ${CMAKE_MAKE_PROGRAM} --version
     OUTPUT_VARIABLE NINJA_VERSION
     OUTPUT_STRIP_TRAILING_WHITESPACE)
   set(NINJA_VERSION ${NINJA_VERSION} CACHE STRING "Ninja version number" FORCE)
   message(STATUS "Ninja version: ${NINJA_VERSION}")
 endif()
 
-if(CMAKE_GENERATOR STREQUAL "Ninja" AND
+if(CMAKE_GENERATOR MATCHES "Ninja" AND
     NOT "${NINJA_VERSION}" VERSION_LESS "1.9.0" AND
     CMAKE_HOST_APPLE AND CMAKE_HOST_SYSTEM_VERSION VERSION_GREATER "15.6.0")
   set(LLVM_TOUCH_STATIC_LIBRARIES ON)
 endif()
 
 if(CMAKE_HOST_APPLE AND APPLE)
   if(NOT CMAKE_XCRUN)
     find_program(CMAKE_XCRUN NAMES xcrun)

llvm/cmake/modules/HandleLLVMOptions.cmake

 set(LLVM_ENABLE_LTO OFF CACHE STRING "Build LLVM with LTO. May be specified as Thin or Full to use a particular kind of LTO")
 string(TOUPPER "${LLVM_ENABLE_LTO}" uppercase_LLVM_ENABLE_LTO)
 
 # Ninja Job Pool support
 # The following only works with the Ninja generator in CMake >= 3.0.
 set(LLVM_PARALLEL_COMPILE_JOBS "" CACHE STRING
   "Define the maximum number of concurrent compilation jobs (Ninja only).")
 if(LLVM_PARALLEL_COMPILE_JOBS)
-  if(NOT CMAKE_GENERATOR STREQUAL "Ninja")
+  if(NOT CMAKE_GENERATOR MATCHES "Ninja")
     message(WARNING "Job pooling is only available with Ninja generators.")
   else()
     set_property(GLOBAL APPEND PROPERTY JOB_POOLS compile_job_pool=${LLVM_PARALLEL_COMPILE_JOBS})
     set(CMAKE_JOB_POOL_COMPILE compile_job_pool)
   endif()
 endif()
 
 set(LLVM_PARALLEL_LINK_JOBS "" CACHE STRING
   "Define the maximum number of concurrent link jobs (Ninja only).")
-if(CMAKE_GENERATOR STREQUAL "Ninja")
+if(CMAKE_GENERATOR MATCHES "Ninja")
   if(NOT LLVM_PARALLEL_LINK_JOBS AND uppercase_LLVM_ENABLE_LTO STREQUAL "THIN")
     message(STATUS "ThinLTO provides its own parallel linking - limiting parallel link jobs to 2.")
     set(LLVM_PARALLEL_LINK_JOBS "2")
   endif()
   if(LLVM_PARALLEL_LINK_JOBS)
     set_property(GLOBAL APPEND PROPERTY JOB_POOLS link_job_pool=${LLVM_PARALLEL_LINK_JOBS})
     set(CMAKE_JOB_POOL_LINK link_job_pool)
   endif()

 endif()
 
 add_definitions( -D__STDC_CONSTANT_MACROS )
 add_definitions( -D__STDC_FORMAT_MACROS )
 add_definitions( -D__STDC_LIMIT_MACROS )
 
 # clang and gcc don't default-print colored diagnostics when invoked from Ninja.
 if (UNIX AND
-    CMAKE_GENERATOR STREQUAL "Ninja" AND
+    CMAKE_GENERATOR MATCHES "Ninja" AND
     (CMAKE_CXX_COMPILER_ID MATCHES "Clang" OR
      (CMAKE_CXX_COMPILER_ID STREQUAL "GNU" AND
       NOT (CMAKE_CXX_COMPILER_VERSION VERSION_LESS 4.9))))
   append("-fdiagnostics-color" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
 endif()
 
 # lld doesn't print colored diagnostics when invoked from Ninja
-if (UNIX AND CMAKE_GENERATOR STREQUAL "Ninja")
+if (UNIX AND CMAKE_GENERATOR MATCHES "Ninja")
   include(LLVMCheckLinkerFlag)
   llvm_check_linker_flag(CXX "-Wl,--color-diagnostics" LINKER_SUPPORTS_COLOR_DIAGNOSTICS)
   append_if(LINKER_SUPPORTS_COLOR_DIAGNOSTICS "-Wl,--color-diagnostics"
     CMAKE_EXE_LINKER_FLAGS CMAKE_MODULE_LINKER_FLAGS CMAKE_SHARED_LINKER_FLAGS)
 endif()
 
 # Add flags for add_dead_strip().
 # FIXME: With MSVS, consider compiling with /Gy and linking with /OPT:REF?

llvm/cmake/modules/TableGen.cmake

 # LLVM_TARGET_DEFINITIONS must contain the name of the .td file to process,
 # while LLVM_TARGET_DEPENDS may contain additional file dependencies.
 # Extra parameters for `tblgen' may come after `ofn' parameter.
 # Adds the name of the generated file to TABLEGEN_OUTPUT.
 
 function(tablegen project ofn)
   # Validate calling context.
   if(NOT ${project}_TABLEGEN_EXE)
     message(FATAL_ERROR "${project}_TABLEGEN_EXE not set")
   endif()
 
   # Use depfile instead of globbing arbitrary *.td(s) for Ninja.
-  if(CMAKE_GENERATOR STREQUAL "Ninja")
+  if(CMAKE_GENERATOR MATCHES "Ninja")
     # Make output path relative to build.ninja, assuming located on
     # ${CMAKE_BINARY_DIR}.
     # CMake emits build targets as relative paths but Ninja doesn't identify
     # absolute path (in *.d) as relative path (in build.ninja)
     # Note that tblgen is executed on ${CMAKE_BINARY_DIR} as working directory.
     file(RELATIVE_PATH ofn_rel
       ${CMAKE_BINARY_DIR} ${CMAKE_CURRENT_BINARY_DIR}/${ofn})
     set(additional_cmdline
function(tablegen project ofn)
   # https://cmake.org/Bug/view.php?id=15858
   # The dependency on both, the target and the file, produces the same
   # dependency twice in the result file when
   # ("${${project}_TABLEGEN_TARGET}" STREQUAL "${${project}_TABLEGEN_EXE}")
   # but lets us having smaller and cleaner code here.
   get_directory_property(tblgen_includes INCLUDE_DIRECTORIES)
   list(TRANSFORM tblgen_includes PREPEND -I)
 
+  set(tablegen_exe ${${project}_TABLEGEN_EXE})
+  set(tablegen_depends ${${project}_TABLEGEN_TARGET} ${tablegen_exe})
+
   add_custom_command(OUTPUT ${CMAKE_CURRENT_BINARY_DIR}/${ofn}
-    COMMAND ${${project}_TABLEGEN_EXE} ${ARGN} -I ${CMAKE_CURRENT_SOURCE_DIR}
+    COMMAND ${tablegen_exe} ${ARGN} -I ${CMAKE_CURRENT_SOURCE_DIR}
     ${tblgen_includes}
     ${LLVM_TABLEGEN_FLAGS}
     ${LLVM_TARGET_DEFINITIONS_ABSOLUTE}
     ${tblgen_change_flag}
     ${additional_cmdline}
     # The file in LLVM_TARGET_DEFINITIONS may be not in the current
     # directory and local_tds may not contain it, so we must
     # explicitly list it here:
-    DEPENDS ${${project}_TABLEGEN_TARGET} ${${project}_TABLEGEN_EXE}
+    DEPENDS ${tablegen_depends}
       ${local_tds} ${global_tds}
     ${LLVM_TARGET_DEFINITIONS_ABSOLUTE}
     ${LLVM_TARGET_DEPENDS}
     COMMENT "Building ${ofn}..."
     )
 
   # `make clean' must remove all those generated files:
   set_property(DIRECTORY APPEND PROPERTY ADDITIONAL_MAKE_CLEAN_FILES ${ofn})
function(add_public_tablegen_target target)
   set(LLVM_COMMON_DEPENDS ${LLVM_COMMON_DEPENDS} ${target} PARENT_SCOPE)
 endfunction()
 
 macro(add_tablegen target project)
   set(${target}_OLD_LLVM_LINK_COMPONENTS ${LLVM_LINK_COMPONENTS})
   set(LLVM_LINK_COMPONENTS ${LLVM_LINK_COMPONENTS} TableGen)
 
   # CMake doesn't let compilation units depend on their dependent libraries on some generators.
-  if(NOT CMAKE_GENERATOR STREQUAL "Ninja" AND NOT XCODE)
+  if(NOT CMAKE_GENERATOR MATCHES "Ninja" AND NOT XCODE)
     # FIXME: It leaks to user, callee of add_tablegen.
     set(LLVM_ENABLE_OBJLIB ON)
   endif()
 
   add_llvm_executable(${target} DISABLE_LLVM_LINK_LLVM_DYLIB ${ARGN})
   set(LLVM_LINK_COMPONENTS ${${target}_OLD_LLVM_LINK_COMPONENTS})
 
   set(${project}_TABLEGEN "${target}" CACHE