latex and latexmk generate some auxiliary files while compiling, which will be edited rarely. So it might be convenient to ignore them when switching buffers (ivy-switch-buffer) or finding files (counsel-find-file), which can be achieved by setting ivy-ignore-buffers and counsel-find-file-ignore-regexp, respectively.

(setq ivy-ignore-tex-aux-suffix '(".aux" ".bbl" ".fls" ".blg" ".nav" ".snm" ".fdb_latexmk" ".run.xml" "-blx.bib" ".toc" ".synctex.gz" ".out"))
(dolist (tex-aux-suffix ivy-ignore-tex-aux-suffix)
  (add-to-list 'ivy-ignore-buffers (concat "\\" tex-aux-suffix))
  (setq counsel-find-file-ignore-regexp (concat "\\(" tex-aux-suffix "$\\)\\|" counsel-find-file-ignore-regexp)))

We can execute the command ivy-toggle-ignore (C-c C-a by default) if we don’t want to hide the ignored buffers or files temporarily.