[mlir][pdll] Add new tablegen helper NFC

Command line option injected by tablegen rule cannot be respected by
PDLL here, so add new helper function that is copy of original without
any additional flags injected. This avoids compilation failure when
compiler warnings are disabled.

Kept it as a mechanical copy.

Fixes #55716

mlir/cmake/modules/AddMLIR.cmake

@@ -9,7 +9,7 @@ function(mlir_tablegen ofn)
   tablegen(MLIR ${ARGV})
   set(TABLEGEN_OUTPUT ${TABLEGEN_OUTPUT} ${CMAKE_CURRENT_BINARY_DIR}/${ofn}
       PARENT_SCOPE)
-      
+
   # Get the current set of include paths for this td file.
   cmake_parse_arguments(ARG "" "" "DEPENDS;EXTRA_INCLUDES" ${ARGN})
   get_directory_property(tblgen_includes INCLUDE_DIRECTORIES)
@@ -37,11 +37,104 @@ endfunction()
 # allows for generating a clean compile_commands on each configure.
 file(REMOVE ${CMAKE_BINARY_DIR}/pdll_compile_commands.yml)
 
+# Declare a helper function/copy of tablegen rule for using tablegen without
+# additional tblgen specific flags when invoking PDLL generator.
+function(_pdll_tablegen project ofn)
+  cmake_parse_arguments(ARG "" "" "DEPENDS;EXTRA_INCLUDES" ${ARGN})
+  # 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 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
+      -o ${ofn_rel}
+      -d ${ofn_rel}.d
+      WORKING_DIRECTORY ${CMAKE_BINARY_DIR}
+      DEPFILE ${CMAKE_CURRENT_BINARY_DIR}/${ofn}.d
+      )
+    set(local_tds)
+    set(global_tds)
+  else()
+    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}
+      )
+  endif()
+
+  if (IS_ABSOLUTE ${LLVM_TARGET_DEFINITIONS})
+    set(LLVM_TARGET_DEFINITIONS_ABSOLUTE ${LLVM_TARGET_DEFINITIONS})
+  else()
+    set(LLVM_TARGET_DEFINITIONS_ABSOLUTE
+      ${CMAKE_CURRENT_SOURCE_DIR}/${LLVM_TARGET_DEFINITIONS})
+  endif()
+
+  if (CMAKE_GENERATOR MATCHES "Visual Studio")
+    # Visual Studio has problems with llvm-tblgen's native --write-if-changed
+    # behavior. Since it doesn't do restat optimizations anyway, just don't
+    # pass --write-if-changed there.
+    set(tblgen_change_flag)
+  else()
+    set(tblgen_change_flag "--write-if-changed")
+  endif()
+
+  # We need both _TABLEGEN_TARGET and _TABLEGEN_EXE in the  DEPENDS list
+  # (both the target and the file) to have .inc files rebuilt on
+  # a tablegen change, as cmake does not propagate file-level dependencies
+  # of custom targets. See the following ticket for more information:
+  # 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(APPEND tblgen_includes ${ARG_EXTRA_INCLUDES})
+  # Filter out empty items before prepending each entry with -I
+  list(REMOVE_ITEM tblgen_includes "")
+  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 ${tablegen_exe} ${ARG_UNPARSED_ARGUMENTS} -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 ${ARG_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})
+
+  set(TABLEGEN_OUTPUT ${TABLEGEN_OUTPUT} ${CMAKE_CURRENT_BINARY_DIR}/${ofn} PARENT_SCOPE)
+  set_source_files_properties(${CMAKE_CURRENT_BINARY_DIR}/${ofn} PROPERTIES
+    GENERATED 1)
+endfunction()
+
 # Declare a PDLL library in the current directory.
 function(add_mlir_pdll_library target inputFile ofn)
   set(LLVM_TARGET_DEFINITIONS ${inputFile})
 
-  tablegen(MLIR_PDLL ${ofn} -x=cpp ${ARGN})
+  _pdll_tablegen(MLIR_PDLL ${ofn} -x=cpp ${ARGN})
   set(TABLEGEN_OUTPUT ${TABLEGEN_OUTPUT} ${CMAKE_CURRENT_BINARY_DIR}/${ofn}
       PARENT_SCOPE)