# Returns the current achitecture name in a variable
#
# Usage:
#   get_swift_host_arch(result_var_name)
#
# If the current architecture is supported by Swift, sets ${result_var_name}
# with the sanitized host architecture name derived from CMAKE_SYSTEM_PROCESSOR.
function(get_swift_host_arch result_var_name)
  if("${CMAKE_SYSTEM_PROCESSOR}" STREQUAL "x86_64")
    set("${result_var_name}" "x86_64" PARENT_SCOPE)
  elseif ("${CMAKE_SYSTEM_PROCESSOR}" MATCHES "AArch64|aarch64|arm64|ARM64")
    if(CMAKE_SYSTEM_NAME MATCHES Darwin)
      set("${result_var_name}" "arm64" PARENT_SCOPE)
    else()
      set("${result_var_name}" "aarch64" PARENT_SCOPE)
    endif()
  elseif("${CMAKE_SYSTEM_PROCESSOR}" STREQUAL "ppc64")
    set("${result_var_name}" "powerpc64" PARENT_SCOPE)
  elseif("${CMAKE_SYSTEM_PROCESSOR}" STREQUAL "ppc64le")
    set("${result_var_name}" "powerpc64le" PARENT_SCOPE)
  elseif("${CMAKE_SYSTEM_PROCESSOR}" STREQUAL "s390x")
    set("${result_var_name}" "s390x" PARENT_SCOPE)
  elseif("${CMAKE_SYSTEM_PROCESSOR}" STREQUAL "armv6l")
    set("${result_var_name}" "armv6" PARENT_SCOPE)
  elseif("${CMAKE_SYSTEM_PROCESSOR}" STREQUAL "armv7-a")
    set("${result_var_name}" "armv7" PARENT_SCOPE)
  elseif("${CMAKE_SYSTEM_PROCESSOR}" STREQUAL "armv7l")
    set("${result_var_name}" "armv7" PARENT_SCOPE)
  elseif("${CMAKE_SYSTEM_PROCESSOR}" STREQUAL "AMD64")
    set("${result_var_name}" "x86_64" PARENT_SCOPE)
  elseif("${CMAKE_SYSTEM_PROCESSOR}" STREQUAL "IA64")
    set("${result_var_name}" "itanium" PARENT_SCOPE)
  elseif("${CMAKE_SYSTEM_PROCESSOR}" STREQUAL "x86")
    set("${result_var_name}" "i686" PARENT_SCOPE)
  elseif("${CMAKE_SYSTEM_PROCESSOR}" STREQUAL "i686")
    set("${result_var_name}" "i686" PARENT_SCOPE)
  else()
    message(FATAL_ERROR "Unrecognized architecture on host system: ${CMAKE_SYSTEM_PROCESSOR}")
  endif()
endfunction()