c-indent-line-or-region is an interactive compiled Lisp function in `cc-cmds.el'.

(c-indent-line-or-region &optional ARG REGION)

Indent active region, current line, or block starting on this line.
In Transient Mark mode, when the region is active, reindent the region.
Otherwise, with a prefix argument, rigidly reindent the expression
starting on the current line.
Otherwise reindent just the current line.