cmake_minimum_required(VERSION 3.12)

if(POLICY CMP0068)
  cmake_policy(SET CMP0068 NEW)
  set(CMAKE_BUILD_WITH_INSTALL_NAME_DIR ON)
endif()

if(POLICY CMP0075)
  cmake_policy(SET CMP0075 NEW)
endif()

if(POLICY CMP0077)
  cmake_policy(SET CMP0077 NEW)
endif()

#-------------------------------------------------------------------------------
# Options and settings
#-------------------------------------------------------------------------------

option(NPCOMP_ENABLE_IREE "Enables the IREE backend (must configure location via IREE_DIR)." OFF)
option(NPCOMP_ENABLE_REFJIT "Enables the reference JIT backend." ON)
option(NPCOMP_BUILD_NPCOMP_DYLIB "Enables shared build of NPCOMP dylib (depends on LLVM/MLIR dylib support)" ON)
set(NPCOMP_IREE_BUILDDIR "../iree-build" CACHE STRING "If building IREE, then setting this elects to build from a source directory (versus installed package)")
set(NPCOMP_ENABLE_PYTORCH "OPTIONAL" CACHE STRING "Enables the PyTorch frontend (OFF, OPTIONAL, REQUIRED)")

# Turn on -gsplit-dwarf if requested in debug builds.
if (NPCOMP_USE_SPLIT_DWARF AND
    ((CMAKE_BUILD_TYPE STREQUAL "Debug") OR
     (CMAKE_BUILD_TYPE STREQUAL "RelWithDebInfo")))
  # Limit to clang and gcc so far. Add compilers supporting this option.
  if (CMAKE_CXX_COMPILER_ID MATCHES "Clang" OR
      CMAKE_CXX_COMPILER_ID STREQUAL "GNU")
    add_compile_options(-gsplit-dwarf)
  endif()
endif()

#-------------------------------------------------------------------------------
# MSVC defaults
#-------------------------------------------------------------------------------

if(MSVC)
    add_compile_options(
        $<$<CONFIG:>:/MD>
        $<$<CONFIG:Debug>:/MD>
        $<$<CONFIG:Release>:/MD>
    )
endif()

if( CMAKE_SOURCE_DIR STREQUAL CMAKE_CURRENT_SOURCE_DIR )
  # If we are not building as a part of LLVM, build NPCOMP as a standalone
  # project, using LLVM as an external library.

  #-------------------------------------------------------------------------------
  # Project setup and globals
  #-------------------------------------------------------------------------------

  project(npcomp LANGUAGES CXX C)
  set(CMAKE_C_STANDARD 11)
  set(CMAKE_CXX_STANDARD 14)

  #-------------------------------------------------------------------------------
  # MLIR/LLVM Configuration
  #-------------------------------------------------------------------------------

  find_package(MLIR REQUIRED CONFIG)
  message(STATUS "Using MLIRConfig.cmake in: ${MLIR_DIR}")
  message(STATUS "Using LLVMConfig.cmake in: ${LLVM_DIR}")

  #set(LLVM_RUNTIME_OUTPUT_INTDIR ${CMAKE_BINARY_DIR}/bin)
  set(LLVM_LIBRARY_OUTPUT_INTDIR ${CMAKE_BINARY_DIR}/lib)

  # Define the default arguments to use with 'lit', and an option for the user to
  # override.
  set(LIT_ARGS_DEFAULT "-sv")
  if (MSVC_IDE OR XCODE)
    set(LIT_ARGS_DEFAULT "${LIT_ARGS_DEFAULT} --no-progress-bar")
  endif()
  set(LLVM_LIT_ARGS "${LIT_ARGS_DEFAULT}" CACHE STRING "Default options for lit")

  list(APPEND CMAKE_MODULE_PATH "${MLIR_CMAKE_DIR}")
  list(APPEND CMAKE_MODULE_PATH "${LLVM_CMAKE_DIR}")
  include(TableGen)
  include(AddLLVM)
  include(AddMLIR)
  include(HandleLLVMOptions)

  set(NPCOMP_BUILT_STANDALONE 1)
  set(BACKEND_PACKAGE_STRING "LLVM ${LLVM_PACKAGE_VERSION}")
else()
  # Otherwise, we are building as a part of LLVM, and we need to set up some
  # variables and includes.

  set(MLIR_MAIN_SRC_DIR ${LLVM_MAIN_SRC_DIR}/../mlir/include ) # --src-root
  set(MLIR_INCLUDE_DIR ${LLVM_MAIN_SRC_DIR}/../mlir/include ) # --includedir
  set(MLIR_TABLEGEN_OUTPUT_DIR ${CMAKE_BINARY_DIR}/tools/mlir/include)
  set(MLIR_TABLEGEN_EXE $<TARGET_FILE:mlir-tblgen>)
  include_directories(SYSTEM ${MLIR_INCLUDE_DIR})
  include_directories(SYSTEM ${MLIR_TABLEGEN_OUTPUT_DIR})

  set(BACKEND_PACKAGE_STRING "${PACKAGE_STRING}")
endif()

list(APPEND CMAKE_MODULE_PATH "${CMAKE_CURRENT_SOURCE_DIR}/cmake/modules")
include(AddNPCOMP)
include(NpcompDetectPythonEnv)
include(ConfigurePyTorch)
include_directories(${LLVM_INCLUDE_DIRS})
include_directories(${MLIR_INCLUDE_DIRS})
include_directories(${CMAKE_CURRENT_SOURCE_DIR}/include)
include_directories(${CMAKE_CURRENT_BINARY_DIR}/include)
link_directories(${LLVM_BUILD_LIBRARY_DIR})
add_definitions(${LLVM_DEFINITIONS})
set(NPCOMP_TABLEGEN_ARGS "")

#-------------------------------------------------------------------------------
# Optional feature selection
#-------------------------------------------------------------------------------

if(NPCOMP_ENABLE_REFJIT)
  add_compile_definitions(NPCOMP_ENABLE_REFJIT)
  message(STATUS "Reference JIT backend enabled")
endif()

#-------------------------------------------------------------------------------
# IREE configuration
#-------------------------------------------------------------------------------

if(NPCOMP_ENABLE_IREE)
  add_compile_definitions(NPCOMP_ENABLE_IREE)
  string(APPEND NPCOMP_TABLEGEN_ARGS "-DNPCOMP_ENABLE_IREE")
  if(NPCOMP_IREE_BUILDDIR)
    message(STATUS "Depending on IREE build: ${NPCOMP_IREE_BUILDDIR}")
    set(IREE_DIR "${NPCOMP_IREE_BUILDDIR}")
    set(IREE_FOUND 1)
  else()
    find_package(IREE REQUIRED CONFIG)
  endif()

  # This is temporary until IREE properly supports installation. We splice
  # the various files into where we want them.
  function(symlink_iree src dst)
    set(full_src_path "${IREE_DIR}/${src}")
    get_filename_component(full_src_path "${full_src_path}" ABSOLUTE)
    set(full_dst_path "${CMAKE_CURRENT_BINARY_DIR}/${dst}")
    get_filename_component(dst_dir ${full_dst_path} PATH)
    file(MAKE_DIRECTORY "${dst_dir}")
    execute_process(
      COMMAND
      ${CMAKE_COMMAND} -E create_symlink "${full_src_path}" "${full_dst_path}"
      RESULT_VARIABLE result
    )
    if(NOT ${result} EQUAL 0)
      message(FATAL_ERROR "Could not symlink iree file: ${full_src_path} -> ${full_dst_path}")
    endif()
  endfunction()
  symlink_iree(iree/tools/iree-translate python/npcomp/compiler/generic/backend/iree-translate)
  symlink_iree(bindings/python/pyiree/rt python/pyiree/rt)
endif()

#-------------------------------------------------------------------------------
# Python Configuration
#-------------------------------------------------------------------------------

set(NPCOMP_PYTHON_BINDINGS_VERSION_LOCKED 1 CACHE BOOL
       "Links to specific python libraries, resolving all symbols.")
find_package(Python3 COMPONENTS Interpreter Development REQUIRED)
message(STATUS "Found python include dirs: ${Python3_INCLUDE_DIRS}")
message(STATUS "Found python libraries: ${Python3_LIBRARIES}")

#-------------------------------------------------------------------------------
# Pytorch Configuration
#-------------------------------------------------------------------------------

NpcompFindPyTorch(${NPCOMP_ENABLE_PYTORCH})

#-------------------------------------------------------------------------------
# Pybind11 Configuration
#-------------------------------------------------------------------------------

npcomp_detect_pybind11_install()
find_package(pybind11 2.6 CONFIG REQUIRED)
set(pybind11_INCLUDE_DIR ${pybind11_INCLUDE_DIR})
message(STATUS "Found pybind11 v${pybind11_VERSION}: ${pybind11_INCLUDE_DIR}")
message(STATUS "Python prefix = '${PYTHON_MODULE_PREFIX}', "
               "suffix = '${PYTHON_MODULE_SUFFIX}', "
               "extension = '${PYTHON_MODULE_EXTENSION}")

#-------------------------------------------------------------------------------
# Directory setup
#-------------------------------------------------------------------------------

set(MLIR_NPCOMP_SOURCE_DIR ${CMAKE_CURRENT_SOURCE_DIR})
set(MLIR_NPCOMP_BINARY_DIR ${CMAKE_CURRENT_BINARY_DIR})

add_custom_target(check-npcomp)
add_custom_target(check-npcomp-all)
add_dependencies(check-npcomp-all check-npcomp)

add_subdirectory(include/npcomp)
add_subdirectory(lib)
add_subdirectory(python)
add_subdirectory(test)

# Tools needs to come late to ensure that NPCOMP_ALL_LIBS is populated.
# Generally things after this point may depend on NPCOMP_ALL_LIBS or libNPCOMP.so.
add_subdirectory(tools)

if(${TORCH_FOUND})
  add_subdirectory(frontends/pytorch)
else()
  message("Skipping pytorch frontend, because PyTorch not found!")
endif()