------------------------------------------------------------------------
-- check whether, in an assignment to a local variable, the local variable
-- is needed in a previous assignment (to a table). If so, save original
-- local value in a safe place and use this safe copy in the previous
-- assignment.
-- * used in assignment()
------------------------------------------------------------------------

function luaY:check_conflict(ls, lh, v)
  local fs = ls.fs
  local extra = fs.freereg  -- eventual position to save local variable
  local conflict = false
  while lh do
    if lh.v.k == "VINDEXED" then
      if lh.v.info == v.info then  -- conflict?
        conflict = true
        lh.v.info = extra  -- previous assignment will use safe copy
      end
      if lh.v.aux == v.info then  -- conflict?
        conflict = true
        lh.v.aux = extra  -- previous assignment will use safe copy
      end
    end
    lh = lh.prev
  end
  if conflict then
    luaK:codeABC(fs, "OP_MOVE", fs.freereg, v.info, 0)  -- make copy
    luaK:reserveregs(fs, 1)
  end
end
