Files
clang-p2996/libc/cmake/modules/LLVMLibCHeaderRules.cmake
Joseph Huber 2a65d0388c [libc] Add support for creating wrapper headers for offloading in clang
This is an alternate approach to the patches proposed in D153897 and
D153794. Rather than exporting a single header that can be included on
the GPU in all circumstances, this patch chooses to instead generate a
separate set of headers that only provides the declarations. This can
then be used by external tooling to set up what's on the GPU. This
leaves room for header hacks for offloading languages without needing to
worry about the `libc` implementation.

Currently this generates a set of headers that only contain the
declarations. These will then be installed to a new clang resource
directory called `llvm_libc_wrappers/` which will house the shim code.
We can then automaticlaly include this from `clang` when offloading to
wrap around the headers while specifying what's on the GPU.

Reviewed By: jdoerfert, JonChesterfield

Differential Revision: https://reviews.llvm.org/D154036
2023-07-07 16:02:33 -05:00

175 lines
5.6 KiB
CMake

# A rule for self contained header file targets.
# This rule merely copies the header file from the current source directory to
# the current binary directory.
# Usage:
# add_header(
# <target name>
# HDR <header file>
# )
function(add_header target_name)
cmake_parse_arguments(
"ADD_HEADER"
"" # No optional arguments
"HDR" # Single value arguments
"DEPENDS"
${ARGN}
)
if(NOT ADD_HEADER_HDR)
message(FATAL_ERROR "'add_header' rules requires the HDR argument specifying a headef file.")
endif()
set(absolute_path ${CMAKE_CURRENT_SOURCE_DIR}/${ADD_HEADER_HDR})
file(RELATIVE_PATH relative_path ${LIBC_INCLUDE_SOURCE_DIR} ${absolute_path})
set(dest_file ${LIBC_INCLUDE_DIR}/${relative_path})
set(src_file ${CMAKE_CURRENT_SOURCE_DIR}/${ADD_HEADER_HDR})
add_custom_command(
OUTPUT ${dest_file}
COMMAND ${CMAKE_COMMAND} -E copy_if_different ${src_file} ${dest_file}
DEPENDS ${src_file}
)
get_fq_target_name(${target_name} fq_target_name)
add_custom_target(
${fq_target_name}
DEPENDS ${dest_file}
)
if(ADD_HEADER_DEPENDS)
get_fq_deps_list(fq_deps_list ${ADD_HEADER_DEPENDS})
# Dependencies of a add_header target can only be another add_header target
# or an add_gen_header target.
foreach(dep IN LISTS fq_deps_list)
get_target_property(header_file ${dep} HEADER_FILE_PATH)
if(NOT header_file)
message(FATAL_ERROR "Invalid dependency '${dep}' for '${fq_target_name}'.")
endif()
endforeach()
add_dependencies(
${fq_target_name} ${fq_deps_list}
)
endif()
set_target_properties(
${fq_target_name}
PROPERTIES
HEADER_FILE_PATH ${dest_file}
DEPS "${fq_deps_list}"
)
endfunction(add_header)
# A rule for generated header file targets.
# Usage:
# add_gen_header(
# <target name>
# DEF_FILE <.h.def file>
# GEN_HDR <generated header file name>
# PARAMS <list of name=value pairs>
# DATA_FILES <list input data files>
# )
function(add_gen_header target_name)
cmake_parse_arguments(
"ADD_GEN_HDR"
"PUBLIC" # No optional arguments
"DEF_FILE;GEN_HDR" # Single value arguments
"PARAMS;DATA_FILES;DEPENDS" # Multi value arguments
${ARGN}
)
get_fq_target_name(${target_name} fq_target_name)
if(NOT LLVM_LIBC_FULL_BUILD)
# We don't want to use generated headers if we are doing a non-full-build.
add_custom_target(${fq_target_name})
return()
endif()
if(NOT ADD_GEN_HDR_DEF_FILE)
message(FATAL_ERROR "`add_gen_hdr` rule requires DEF_FILE to be specified.")
endif()
if(NOT ADD_GEN_HDR_GEN_HDR)
message(FATAL_ERROR "`add_gen_hdr` rule requires GEN_HDR to be specified.")
endif()
set(absolute_path ${CMAKE_CURRENT_SOURCE_DIR}/${ADD_GEN_HDR_GEN_HDR})
file(RELATIVE_PATH relative_path ${LIBC_INCLUDE_SOURCE_DIR} ${absolute_path})
set(out_file ${LIBC_INCLUDE_DIR}/${relative_path})
set(in_file ${CMAKE_CURRENT_SOURCE_DIR}/${ADD_GEN_HDR_DEF_FILE})
set(fq_data_files "")
if(ADD_GEN_HDR_DATA_FILES)
foreach(data_file IN LISTS ADD_GEN_HDR_DATA_FILES)
list(APPEND fq_data_files "${CMAKE_CURRENT_SOURCE_DIR}/${data_file}")
endforeach(data_file)
endif()
set(replacement_params "")
if(ADD_GEN_HDR_PARAMS)
list(APPEND replacement_params "--args" ${ADD_GEN_HDR_PARAMS})
endif()
set(gen_hdr_script "${LIBC_BUILD_SCRIPTS_DIR}/gen_hdr.py")
file(GLOB td_includes ${LIBC_SOURCE_DIR}/spec/*.td)
set(ENTRYPOINT_NAME_LIST_ARG ${TARGET_ENTRYPOINT_NAME_LIST})
list(TRANSFORM ENTRYPOINT_NAME_LIST_ARG PREPEND "--e=")
if(LIBC_HDRGEN_EXE)
set(hdrgen_exe ${LIBC_HDRGEN_EXE})
else()
set(hdrgen_exe ${LIBC_TABLEGEN_EXE})
set(hdrgen_deps "${LIBC_TABLEGEN_EXE};${LIBC_TABLEGEN_TARGET}")
endif()
add_custom_command(
OUTPUT ${out_file}
COMMAND ${hdrgen_exe} -o ${out_file} --header ${ADD_GEN_HDR_GEN_HDR}
--def ${in_file} ${replacement_params} -I ${LIBC_SOURCE_DIR}
${ENTRYPOINT_NAME_LIST_ARG}
${LIBC_SOURCE_DIR}/config/${LIBC_TARGET_OS}/api.td
WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}
DEPENDS ${in_file} ${fq_data_files} ${td_includes}
${LIBC_SOURCE_DIR}/config/${LIBC_TARGET_OS}/api.td
${hdrgen_deps}
)
if(LIBC_TARGET_ARCHITECTURE_IS_GPU)
file(MAKE_DIRECTORY ${LIBC_INCLUDE_DIR}/llvm-libc-decls)
set(decl_out_file ${LIBC_INCLUDE_DIR}/llvm-libc-decls/${relative_path})
add_custom_command(
OUTPUT ${decl_out_file}
COMMAND ${hdrgen_exe} -o ${decl_out_file}
--header ${ADD_GEN_HDR_GEN_HDR} --def ${in_file} --export-decls
${replacement_params} -I ${LIBC_SOURCE_DIR} ${ENTRYPOINT_NAME_LIST_ARG}
${LIBC_SOURCE_DIR}/config/${LIBC_TARGET_OS}/api.td
WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}
DEPENDS ${in_file} ${fq_data_files} ${td_includes}
${LIBC_SOURCE_DIR}/config/${LIBC_TARGET_OS}/api.td
${hdrgen_deps}
)
endif()
if(ADD_GEN_HDR_DEPENDS)
get_fq_deps_list(fq_deps_list ${ADD_GEN_HDR_DEPENDS})
# Dependencies of a add_header target can only be another add_gen_header target
# or an add_header target.
foreach(dep IN LISTS fq_deps_list)
get_target_property(header_file ${dep} HEADER_FILE_PATH)
if(NOT header_file)
message(FATAL_ERROR "Invalid dependency '${dep}' for '${fq_target_name}'.")
endif()
endforeach()
endif()
add_custom_target(
${fq_target_name}
DEPENDS ${out_file} ${fq_deps_list} ${decl_out_file}
)
set_target_properties(
${fq_target_name}
PROPERTIES
HEADER_FILE_PATH ${out_file}
DECLS_FILE_PATH "${decl_out_file}"
DEPS "${fq_deps_list}"
)
endfunction(add_gen_header)