Files
clang-p2996/flang-rt/CMakeLists.txt
Michael Kruse b55f7512a7 [Flang] LLVM_ENABLE_RUNTIMES=flang-rt (#110217)
Extract Flang's runtime library to use the LLVM_ENABLE_RUNTIME
mechanism. It will only become active when
`LLVM_ENABLE_RUNTIMES=flang-rt` is used, which also changes the
`FLANG_INCLUDE_RUNTIME` to `OFF` so the old runtime build rules do not
conflict. This also means that unless `LLVM_ENABLE_RUNTIMES=flang-rt` is
passed, nothing changes with the current build process.

Motivation:
* Consistency with LLVM's other runtime libraries (compiler-rt, libc,
libcxx, openmp offload, ...)
* Allows compiling the runtime for multiple targets at once using the
LLVM_RUNTIME_TARGETS configuration options
* Installs the runtime into the compiler's per-target resource directory
so it can be automatically found even when cross-compiling

Also see RFC discussion at
https://discourse.llvm.org/t/rfc-use-llvm-enable-runtimes-for-flangs-runtime/80826
2025-02-16 15:39:52 +01:00

262 lines
9.4 KiB
CMake

#===-- CMakeLists.txt ------------------------------------------------------===#
#
# Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
# See https://llvm.org/LICENSE.txt for license information.
# SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
#
#===------------------------------------------------------------------------===#
#
# Build instructions for the flang-rt library. This is file is intended to be
# included using the LLVM_ENABLE_RUNTIMES mechanism.
#
#===------------------------------------------------------------------------===#
if (NOT LLVM_RUNTIMES_BUILD)
message(FATAL_ERROR "Use this CMakeLists.txt from LLVM's runtimes build system.
Example:
cmake <llvm-project>/runtimes -DLLVM_ENABLE_RUNTIMES=flang-rt
")
endif ()
set(LLVM_SUBPROJECT_TITLE "Flang-RT")
set(FLANG_RT_SOURCE_DIR "${CMAKE_CURRENT_SOURCE_DIR}")
set(FLANG_RT_BINARY_DIR "${CMAKE_CURRENT_BINARY_DIR}")
set(FLANG_SOURCE_DIR "${CMAKE_CURRENT_SOURCE_DIR}/../flang")
# CMake 3.24 is the first version of CMake that directly recognizes Flang.
# LLVM's requirement is only CMake 3.20, teach CMake 3.20-3.23 how to use Flang.
if (CMAKE_VERSION VERSION_LESS "3.24")
cmake_path(GET CMAKE_Fortran_COMPILER STEM _Fortran_COMPILER_STEM)
if (_Fortran_COMPILER_STEM STREQUAL "flang-new" OR _Fortran_COMPILER_STEM STREQUAL "flang")
include(CMakeForceCompiler)
CMAKE_FORCE_Fortran_COMPILER("${CMAKE_Fortran_COMPILER}" "LLVMFlang")
set(CMAKE_Fortran_COMPILER_ID "LLVMFlang")
set(CMAKE_Fortran_COMPILER_VERSION "${LLVM_VERSION_MAJOR}.${LLVM_VERSION_MINOR}")
set(CMAKE_Fortran_SUBMODULE_SEP "-")
set(CMAKE_Fortran_SUBMODULE_EXT ".mod")
set(CMAKE_Fortran_PREPROCESS_SOURCE
"<CMAKE_Fortran_COMPILER> -cpp <DEFINES> <INCLUDES> <FLAGS> -E <SOURCE> > <PREPROCESSED_SOURCE>")
set(CMAKE_Fortran_FORMAT_FIXED_FLAG "-ffixed-form")
set(CMAKE_Fortran_FORMAT_FREE_FLAG "-ffree-form")
set(CMAKE_Fortran_MODDIR_FLAG "-module-dir")
set(CMAKE_Fortran_COMPILE_OPTIONS_PREPROCESS_ON "-cpp")
set(CMAKE_Fortran_COMPILE_OPTIONS_PREPROCESS_OFF "-nocpp")
set(CMAKE_Fortran_POSTPROCESS_FLAG "-ffixed-line-length-72")
set(CMAKE_Fortran_COMPILE_OPTIONS_TARGET "--target=")
set(CMAKE_Fortran_LINKER_WRAPPER_FLAG "-Wl,")
set(CMAKE_Fortran_LINKER_WRAPPER_FLAG_SEP ",")
endif ()
endif ()
enable_language(Fortran)
list(APPEND CMAKE_MODULE_PATH
"${FLANG_RT_SOURCE_DIR}/cmake/modules"
"${FLANG_SOURCE_DIR}/cmake/modules"
)
include(AddFlangRT)
include(GetToolchainDirs)
include(FlangCommon)
include(HandleCompilerRT)
include(ExtendPath)
############################
# Build Mode Introspection #
############################
# Determine whether we are in the runtimes/runtimes-bins directory of a
# bootstrap build.
set(LLVM_TREE_AVAILABLE OFF)
if (LLVM_LIBRARY_OUTPUT_INTDIR AND LLVM_RUNTIME_OUTPUT_INTDIR AND PACKAGE_VERSION)
set(LLVM_TREE_AVAILABLE ON)
endif()
# Path to LLVM development tools (FileCheck, llvm-lit, not, ...)
set(LLVM_TOOLS_DIR "${LLVM_BINARY_DIR}/bin")
# Determine build and install paths.
# The build path is absolute, but the install dir is relative, CMake's install
# command has to apply CMAKE_INSTALL_PREFIX itself.
get_toolchain_library_subdir(toolchain_lib_subdir)
if (LLVM_TREE_AVAILABLE)
# In a bootstrap build emit the libraries into a default search path in the
# build directory of the just-built compiler. This allows using the
# just-built compiler without specifying paths to runtime libraries.
#
# Despite Clang in the name, get_clang_resource_dir does not depend on Clang
# being added to the build. Flang uses the same resource dir as clang.
include(GetClangResourceDir)
get_clang_resource_dir(FLANG_RT_OUTPUT_RESOURCE_DIR PREFIX "${LLVM_LIBRARY_OUTPUT_INTDIR}/..")
get_clang_resource_dir(FLANG_RT_INSTALL_RESOURCE_PATH)
extend_path(FLANG_RT_OUTPUT_RESOURCE_LIB_DIR "${FLANG_RT_OUTPUT_RESOURCE_DIR}" "${toolchain_lib_subdir}")
else ()
# In a standalone runtimes build, do not write into LLVM_BINARY_DIR. It may be
# read-only and/or shared by multiple runtimes with different build
# configurations (e.g. Debug/Release). Use the runtime's own lib dir like any
# non-toolchain library.
# For the install prefix, still use the resource dir assuming that Flang will
# be installed there using the same prefix. This is to not have a difference
# between bootstrap and standalone runtimes builds.
set(FLANG_RT_OUTPUT_RESOURCE_DIR "${CMAKE_CURRENT_BINARY_DIR}")
set(FLANG_RT_INSTALL_RESOURCE_PATH "lib${LLVM_LIBDIR_SUFFIX}/clang/${LLVM_VERSION_MAJOR}")
extend_path(FLANG_RT_OUTPUT_RESOURCE_LIB_DIR "${FLANG_RT_OUTPUT_RESOURCE_DIR}" "lib${LLVM_LIBDIR_SUFFIX}")
endif ()
extend_path(FLANG_RT_INSTALL_RESOURCE_LIB_PATH "${FLANG_RT_INSTALL_RESOURCE_PATH}" "${toolchain_lib_subdir}")
cmake_path(NORMAL_PATH FLANG_RT_OUTPUT_RESOURCE_DIR)
cmake_path(NORMAL_PATH FLANG_RT_INSTALL_RESOURCE_PATH)
cmake_path(NORMAL_PATH FLANG_RT_OUTPUT_RESOURCE_LIB_DIR)
cmake_path(NORMAL_PATH FLANG_RT_INSTALL_RESOURCE_LIB_PATH)
#################
# Build Options #
#################
# Important: flang-rt user options must be prefixed with "FLANG_RT_". Variables
# with this prefix will be forwarded in bootstrap builds.
option(FLANG_RT_INCLUDE_TESTS "Generate build targets for the flang-rt unit and regression-tests." "${LLVM_INCLUDE_TESTS}")
set(FLANG_RT_EXPERIMENTAL_OFFLOAD_SUPPORT "" CACHE STRING "Compile Flang-RT with GPU support (CUDA or OpenMP)")
set_property(CACHE FLANG_RT_EXPERIMENTAL_OFFLOAD_SUPPORT PROPERTY STRINGS
""
CUDA
OpenMP
)
if (NOT FLANG_RT_EXPERIMENTAL_OFFLOAD_SUPPORT)
# Support for GPUs disabled
elseif (FLANG_RT_EXPERIMENTAL_OFFLOAD_SUPPORT STREQUAL "CUDA")
# Support for CUDA
set(FLANG_RT_LIBCUDACXX_PATH "" CACHE PATH "Path to libcu++ package installation")
option(FLANG_RT_CUDA_RUNTIME_PTX_WITHOUT_GLOBAL_VARS "Do not compile global variables' definitions when producing PTX library" OFF)
elseif (FLANG_RT_EXPERIMENTAL_OFFLOAD_SUPPORT STREQUAL "OpenMP")
# Support for OpenMP offloading
set(FLANG_RT_DEVICE_ARCHITECTURES "all" CACHE STRING
"List of OpenMP device architectures to be used to compile the Fortran runtime (e.g. 'gfx1103;sm_90')"
)
if (FLANG_RT_DEVICE_ARCHITECTURES STREQUAL "all")
# TODO: support auto detection on the build system.
set(all_amdgpu_architectures
"gfx700;gfx701;gfx801;gfx803;gfx900;gfx902;gfx906"
"gfx908;gfx90a;gfx90c;gfx940;gfx1010;gfx1030"
"gfx1031;gfx1032;gfx1033;gfx1034;gfx1035;gfx1036"
"gfx1100;gfx1101;gfx1102;gfx1103;gfx1150;gfx1151"
"gfx1152;gfx1153")
set(all_nvptx_architectures
"sm_35;sm_37;sm_50;sm_52;sm_53;sm_60;sm_61;sm_62"
"sm_70;sm_72;sm_75;sm_80;sm_86;sm_89;sm_90")
set(all_gpu_architectures
"${all_amdgpu_architectures};${all_nvptx_architectures}")
set(FLANG_RT_DEVICE_ARCHITECTURES ${all_gpu_architectures})
endif()
list(REMOVE_DUPLICATES FLANG_RT_DEVICE_ARCHITECTURES)
else ()
message(FATAL_ERROR "Invalid value '${FLANG_RT_EXPERIMENTAL_OFFLOAD_SUPPORT}' for FLANG_RT_EXPERIMENTAL_OFFLOAD_SUPPORT; must be empty, 'CUDA', or 'OpenMP'")
endif ()
option(FLANG_RT_INCLUDE_CUF "Build the CUDA Fortran runtime (libflang_rt.cuda.a)" OFF)
if (FLANG_RT_INCLUDE_CUF)
find_package(CUDAToolkit REQUIRED)
endif()
########################
# System Introspection #
########################
include(CheckCXXSymbolExists)
include(CheckCXXSourceCompiles)
check_cxx_symbol_exists(strerror_r string.h HAVE_STRERROR_R)
# Can't use symbol exists here as the function is overloaded in C++
check_cxx_source_compiles(
"#include <string.h>
int main() {
char buf[4096];
return strerror_s(buf, 4096, 0);
}
"
HAVE_DECL_STRERROR_S)
# Search for clang_rt.builtins library. Need in addition to msvcrt.
if (WIN32)
find_compiler_rt_library(builtins FLANG_RT_BUILTINS_LIBRARY)
endif ()
# Check whether the compiler can undefine a macro using the "-U" flag.
# Aternatively, we could use
# CMAKE_CXX_COMPILER_FRONTEND_VARIANT STREQUAL "GNU"
# but some older versions of CMake don't define it for GCC itself.
check_cxx_compiler_flag("-UTESTFLAG" FLANG_RT_SUPPORTS_UNDEFINE_FLAG)
# Check whether -fno-lto is supported.
check_cxx_compiler_flag(-fno-lto FLANG_RT_HAS_FNO_LTO_FLAG)
# function checks
find_package(Backtrace)
set(HAVE_BACKTRACE ${Backtrace_FOUND})
set(BACKTRACE_HEADER ${Backtrace_HEADER})
#####################
# Build Preparation #
#####################
if (FLANG_RT_EXPERIMENTAL_OFFLOAD_SUPPORT AND FLANG_RT_INCLUDE_TESTS)
# If Fortran runtime is built as CUDA library, the linking
# of targets that link flang-rt must be done
# with CUDA_RESOLVE_DEVICE_SYMBOLS.
# CUDA language must be enabled for CUDA_RESOLVE_DEVICE_SYMBOLS
# to take effect.
enable_language(CUDA)
endif()
# C++17 is required for flang-rt; user or other runtimes may override this.
# GTest included later also requires C++17.
set(CMAKE_CXX_STANDARD 17 CACHE STRING "C++ standard to conform to")
set(CMAKE_CXX_STANDARD_REQUIRED YES)
configure_file(cmake/config.h.cmake.in config.h)
# The bootstrap build will create a phony target with the same as the top-level
# directory ("flang-rt") and delegate it to the runtimes build dir.
# AddFlangRT will add all non-EXCLUDE_FROM_ALL targets to it.
add_custom_target(flang-rt)
###################
# Build Artifacts #
###################
add_subdirectory(lib)
if (LLVM_INCLUDE_EXAMPLES)
add_subdirectory(examples)
endif ()
if (FLANG_RT_INCLUDE_TESTS)
add_subdirectory(unittests)
add_subdirectory(test)
else ()
add_custom_target(check-flang-rt)
endif()