# Copyright (c) 2016 Hartmut Kaiser
#
# SPDX-License-Identifier: BSL-1.0
# Distributed under the Boost Software License, Version 1.0. (See accompanying
# file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)

# Locate the Vc template library. Vc can be found at
# https://github.com/VcDevel/Vc
#
# This file is meant to be copied into projects that want to use Vc. It will
# search for VcConfig.cmake, which ships with Vc and will provide up-to-date
# buildsystem changes. Thus there should not be any need to update FindVc.cmake
# again after you integrated it into your project.
#
# This module defines the following variables: Vc_FOUND Vc_INCLUDE_DIR
# Vc_LIBRARIES Vc_DEFINITIONS Vc_COMPILE_FLAGS Vc_ARCHITECTURE_FLAGS
# Vc_ALL_FLAGS (the union of the above three variables) Vc_VERSION_MAJOR
# Vc_VERSION_MINOR Vc_VERSION_PATCH Vc_VERSION Vc_VERSION_STRING Vc_INSTALL_DIR
# Vc_LIB_DIR Vc_CMAKE_MODULES_DIR
#
# The following two variables are set according to the compiler used. Feel free
# to use them to skip whole compilation units. Vc_SSE_INTRINSICS_BROKEN
# Vc_AVX_INTRINSICS_BROKEN

if(("${HPX_WITH_DATAPAR_BACKEND}" STREQUAL "VC") AND NOT TARGET Vc::vc)
  find_package(Vc ${Vc_FIND_VERSION} QUIET)

  if(NOT Vc_FOUND)
    if(NOT Vc_VERSION_STRING)
      # didn't find any version of Vc
      hpx_error(
        "Vc was not found while datapar support was requested. Set Vc_DIR to the installation path of Vc"
      )
    elseif(${Vc_VERSION_STRING} VERSION_LESS "1.70.0")
      # didn't find current version of Vc
      hpx_error(
        "The Vc was found for requested datapar support was too old. Set Vc_DIR to the installation path of Vc (V1.70.0 is required)"
      )
    endif()
  endif()

  if(Vc_VERSION_STRING AND (NOT ${Vc_VERSION_STRING} VERSION_LESS "1.70.0"))
    # found Vc V2
    if(NOT Vc_INCLUDE_DIR)
      hpx_error(
        "Vc was not found while datapar support was requested. Set Vc_DIR to the installation path of Vc"
      )
    endif()
    set(HPX_WITH_DATAPAR_VC_NO_LIBRARY On)
  endif()

  add_library(Vc::vc INTERFACE IMPORTED)
  target_include_directories(Vc::vc SYSTEM INTERFACE ${Vc_INCLUDE_DIR})

  if(NOT HPX_WITH_DATAPAR_VC_NO_LIBRARY)
    target_link_libraries(Vc::vc INTERFACE ${Vc_LIBRARIES})
    target_link_directories(Vc::vc INTERFACE ${Vc_LIB_DIR})
  endif()

  foreach(_flag ${Vc_DEFINITIONS})
    # remove leading '-D'
    string(STRIP ${_flag} _flag)
    string(FIND ${_flag} "-D" _flagpos)
    if(${_flagpos} EQUAL 0)
      string(SUBSTRING ${_flag} 2 -1 _flag)
    endif()

    target_compile_definitions(Vc::vc INTERFACE ${_flag})
  endforeach()

  include(HPX_AddDefinitions)

  # do not include Vc build flags for MSVC builds as this breaks building the
  # core HPX libraries itself
  if(NOT MSVC)
    target_compile_options(
      Vc::vc INTERFACE ${Vc_COMPILE_FLAGS} ${Vc_ARCHITECTURE_FLAGS}
    )
  else()
    hpx_add_config_cond_define(_SILENCE_ALL_CXX17_DEPRECATION_WARNINGS)
    hpx_add_config_cond_define(_SILENCE_ALL_CXX20_DEPRECATION_WARNINGS)
  endif()

  hpx_info("Found Vc (vectorization):" ${Vc_INCLUDE_DIR} "- version:"
           ${Vc_VERSION_STRING}
  )
endif()