impc:ir:compiler:pointer-ref   scheme

(define impc:ir:compiler:pointer-ref
  (lambda (ast types)
    (let* ((os (make-string 0))
           (index-str (impc:ir:compiler (caddr ast) types))
           (idx (impc:ir:gname))
           (var-str (impc:ir:compiler (cadr ast) types))
           (var (impc:ir:gname))
           (ttype (impc:ir:get-type-from-str (cadr var)))
           (tt '()))
      ;; type tests
      (if (not (impc:ir:pointer? ttype))
          (impc:compiler:print-bad-type-error-with-ast (cadr var) "array must take a pointer to an array" ast))
      (if (not (impc:ir:fixed-point? (impc:ir:get-type-from-str (cadr idx))))
          (impc:compiler:print-bad-type-error-with-ast (cadr idx) "index must be an integer" ast))
      (emit index-str os)
      (emit var-str os)
      (emit "; pointer ref\n" os)
      (if (not (impc:ir:pointer? ttype)) ;; must be an array if we're not a pointer
          (emit (string-append (impc:ir:gname "val" (impc:ir:get-type-str (caddr ttype))) " = extractvalue "
                               (cadr var) " " (car var) ", " (car idx) "\n") os)
          (begin (emit (string-append (impc:ir:gname "val" (cadr var)) " = getelementptr "
                                      (impc:ir:pointer-- (cadr var)) ", " (cadr var) " " (car var) ", " (cadr idx) " " (car idx) "\n") os)
                 (set! tt (impc:ir:get-type-str (impc:ir:pointer-- (impc:ir:get-type-from-str (cadr var)))))))
      (if (impc:ir:pointer? ttype)
          (emit (string-append (impc:ir:gname "val" tt) " = load " tt ", " tt "* "
                               (car (impc:ir:gname 1)) "\n") os))
      (impc:ir:strip-space os))))