(stack-slot nil :type (or null index))
(label (sb!assem:gen-label) :type sb!assem:label)
(duplicate nil :type (member t nil)))
(defstruct (byte-block-info
(stack-slot nil :type (or null index))
(label (sb!assem:gen-label) :type sb!assem:label)
(duplicate nil :type (member t nil)))
(defstruct (byte-block-info