cmake_minimum_required(VERSION 3.18 FATAL_ERROR)
project(c10 CXX)

set(CMAKE_CXX_STANDARD 17 CACHE STRING "The C++ standard whose features are requested to build this target.")
set(CMAKE_EXPORT_COMPILE_COMMANDS ON)

# Main build file for the C10 library.
#
# Note that the C10 library should maintain minimal dependencies - especially,
# it should not depend on any library that is implementation specific or
# backend specific. It should in particular NOT be dependent on any generated
# protobuf header files, because protobuf header files will transitively force
# one to link against a specific protobuf version.

if(BUILD_LIBTORCHLESS)
  find_library(C10_LIB c10 PATHS $ENV{LIBTORCH_LIB_PATH} NO_DEFAULT_PATH)
else()
  set(C10_LIB c10)
endif()

  # ---[ Configure macro file.
  set(C10_USE_GFLAGS ${USE_GFLAGS}) # used in cmake_macros.h.in
  set(C10_USE_GLOG ${USE_GLOG}) # used in cmake_macros.h.in
  set(C10_BUILD_SHARED_LIBS ${BUILD_SHARED_LIBS}) # used in cmake_macros.h.in
  set(C10_USE_NUMA ${USE_NUMA})
  set(C10_USE_MSVC_STATIC_RUNTIME ${CAFFE2_USE_MSVC_STATIC_RUNTIME})
  set(C10_USE_ROCM_KERNEL_ASSERT ${USE_ROCM_KERNEL_ASSERT})
  configure_file(
      ${CMAKE_CURRENT_LIST_DIR}/macros/cmake_macros.h.in
      ${CMAKE_BINARY_DIR}/c10/macros/cmake_macros.h)

  # Note: if you want to add ANY dependency to the c10 library, make sure you
  # check with the core PyTorch developers as the dependency will be
  # transitively passed on to all libraries dependent on PyTorch.
  file(GLOB C10_SRCS
          *.cpp
          core/*.cpp
          core/impl/*.cpp
          mobile/*.cpp
          macros/*.cpp
          util/*.cpp
        )
  file(GLOB C10_HEADERS
          *.h
          core/*.h
          core/impl/*.h
          mobile/*.h
          macros/*.h
          util/*.h
        )
if(NOT BUILD_LIBTORCHLESS)
  add_library(c10 ${C10_SRCS} ${C10_HEADERS})
  target_compile_options_if_supported(c10 "-Wdeprecated")
  if(HAVE_SOVERSION)
    set_target_properties(c10 PROPERTIES
        VERSION ${TORCH_VERSION} SOVERSION ${TORCH_SOVERSION})
  endif()
  # If building shared library, set dllimport/dllexport proper.
  target_compile_options(c10 PRIVATE "-DC10_BUILD_MAIN_LIB")
  # Enable hidden visibility if compiler supports it.
  if(${COMPILER_SUPPORTS_HIDDEN_VISIBILITY})
    target_compile_options(c10 PRIVATE "-fvisibility=hidden")
  endif()

  option(C10_USE_IWYU "Use include-what-you-use to clean up header inclusion" OFF)
  if(C10_USE_IWYU)
    find_program(iwyu NAMES include-what-you-use)
    if(iwyu)
      set(iwyu_cmd
          "include-what-you-use"
          "-Xiwyu"
          "--transitive_includes_only"
          "-Xiwyu"
          "--no_fwd_decls"
          "-Xiwyu"
          "--prefix_header_includes=keep"
          "-Xiwyu"
          "--mapping_file=${CMAKE_CURRENT_LIST_DIR}/../tools/iwyu/all.imp"
        )
      set_property(TARGET c10 PROPERTY CXX_INCLUDE_WHAT_YOU_USE ${iwyu_cmd})
    endif()
  endif()

  if(WERROR)
    target_compile_options_if_supported(c10 PRIVATE "-Werror=sign-compare")
    target_compile_options_if_supported(c10 PRIVATE "-Werror=shadow")
  endif()

  # ---[ Dependency of c10
  if(C10_USE_GFLAGS)
    target_link_libraries(c10 PUBLIC gflags)
  endif()

  if(C10_USE_GLOG)
    target_link_libraries(c10 PUBLIC glog::glog)
  endif()
  target_link_libraries(c10 PRIVATE fmt::fmt-header-only)
  target_link_libraries(c10 PRIVATE nlohmann)

  if(C10_USE_NUMA)
    message(STATUS "NUMA paths:")
    message(STATUS ${Numa_INCLUDE_DIR})
    message(STATUS ${Numa_LIBRARIES})
    target_include_directories(c10 PRIVATE ${Numa_INCLUDE_DIR})
    target_link_libraries(c10 PRIVATE ${Numa_LIBRARIES})
  else()
    message(STATUS "don't use NUMA")
  endif()

  if(NOT CMAKE_SYSTEM_PROCESSOR MATCHES "s390x" AND NOT CMAKE_SYSTEM_PROCESSOR MATCHES "ppc64le")
    target_link_libraries(c10 PRIVATE cpuinfo)
  endif()

  find_package(Backtrace)
  if(Backtrace_FOUND)
    target_include_directories(c10 PRIVATE ${Backtrace_INCLUDE_DIRS})
    target_link_libraries(c10 PRIVATE ${Backtrace_LIBRARIES})
    target_compile_definitions(c10 PRIVATE SUPPORTS_BACKTRACE=1)
  else()
    target_compile_definitions(c10 PRIVATE SUPPORTS_BACKTRACE=0)
  endif()

  if(USE_MIMALLOC)
    target_link_libraries(c10 PRIVATE "mimalloc-static")
    add_dependencies(c10 mimalloc-static)
  endif()

  if(LINUX)
    target_link_libraries(c10 PRIVATE Threads::Threads)
  endif()

  if(ANDROID)
    target_link_libraries(c10 PRIVATE log)
  endif()

  target_include_directories(
      c10 PUBLIC
      $<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}/../>
      $<BUILD_INTERFACE:${CMAKE_BINARY_DIR}>
      $<INSTALL_INTERFACE:include>)
endif()

add_subdirectory(test)
add_subdirectory(benchmark)

if(USE_CUDA)
  add_subdirectory(cuda)
endif()

if(USE_ROCM)
  # NB: This directory is generated by the HIPIFY script; it's
  # not checked in
  add_subdirectory(hip)
endif()

if(USE_XPU)
  add_subdirectory(xpu)
endif()

if(NOT BUILD_LIBTORCHLESS)
  # ---[ Installation
  # Note: for now, we will put all export path into one single Caffe2Targets group
  # to deal with the cmake deployment need. Inside the Caffe2Targets set, the
  # individual libraries like libc10.so and libcaffe2.so are still self-contained.
  install(TARGETS c10 EXPORT Caffe2Targets DESTINATION lib)
endif()

install(DIRECTORY ${CMAKE_CURRENT_LIST_DIR}
        DESTINATION include
        FILES_MATCHING PATTERN "*.h")
install(FILES ${CMAKE_BINARY_DIR}/c10/macros/cmake_macros.h
        DESTINATION include/c10/macros)

if(MSVC AND C10_BUILD_SHARED_LIBS)
  install(FILES $<TARGET_PDB_FILE:c10> DESTINATION lib OPTIONAL)
endif()