#lang racket

(provide uncover-locals)

(define (uncover-locals p)
  (match p
    [`(program ,data ,c0-blocks)
     `(program ,(append data (cons `locals (uncover-locals-blocks c0-blocks))) c0-blocks)]))

(define (uncover-locals-blocks c0-blocks)
  (if (empty? c0-blocks)
    `()
    (append (uncover-locals-block (car c0-blocks)) (uncover-locals-blocks (cdr c0-blocks)))))

(define (uncover-locals-block c0-block)
  (match c0-block
   [`(,label . ,tail) (uncover-locals-tail tail)]))

(define (uncover-locals-tail c0-tail)
  (match c0-tail
    [`(return ,exp) `()]
    [`(seq (assign ,var ,exp) ,next) (cons var (uncover-locals-tail next))]))