func! s:get_visual_selection_list() abort
  let [lnum1, col1] = getpos("'<")[1:2]
  let [lnum2, col2] = getpos("'>")[1:2]
  let lines = getline(lnum1, lnum2)
  let lines[-1] = lines[-1][: col2 - (&selection ==? 'inclusive' ? 1 : 2)]
  let lines[0] = lines[0][col1 - 1:]
  return lines
endf

func! s:get_visual_selection_searchpattern() abort
  let lines = s:get_visual_selection_list()
  let lines = map(lines, 'escape(v:val, ''/\'')')
  " Join with a _literal_ \n to make a valid search pattern.
  return join(lines, '\n')
endf

" Read last visual-selection into command line
cnoremap <c-r><c-v> <c-r>=join(<sid>get_visual_selection_list(), " ")<CR>
inoremap <c-r><c-v> <c-r>=join(<sid>get_visual_selection_list(), " ")<CR>

xnoremap * <esc>ms/\V<c-r>=<sid>get_visual_selection_searchpattern()<CR><CR>
nnoremap <silent> *  ms:<c-u>let @/='\V\<'.escape(expand('<cword>'), '/\').'\>'<Bar>call histadd('/',@/)<CR>
nnoremap <silent> g* ms:<c-u>let @/='\V' . escape(expand('<cword>'), '/\')     <Bar>call histadd('/',@/)<CR>

" Use the setting of mark trick for backward search as well.
nnoremap <silent> #  ms#<CR>
nnoremap <silent> g# msg#<CR>