bits bits bits

;; for floats, sb-kernel:single-float-bits, sb-kernel:make-single-float 
;; etc.

(eval-when (:compile-toplevel :load-toplevel :execute)
  (defun mkstr (&rest args)
    (format nil "~{~a~}" args))
  (defun mksymb (&rest args)
    (intern (apply #'mkstr args))))

(defmacro signed-unsigned-convertors (size)
  `(progn
     (defun ,(mksymb 'sb size '-> 'ub size) (sb)
       (declare (optimize (debug 0) (safety 0) (speed 3))
                (type (integer ,(- (expt 2 (1- size))) ,(1- (expt 2 (1- size)))) sb))
       (if (< sb 0)
           (ldb (byte ,size 0) sb)
           sb))
     (defun ,(mksymb 'ub size '-> 'sb size) (sb)
       (declare (optimize (debug 0) (safety 0) (speed 3))
                (type (mod ,(expt 2 size)) sb))
       (if (logbitp (1- ,size) sb)
           (- (1+ (logxor (1- (expt 2 ,size)) sb)))
           sb))))

(signed-unsigned-convertors 8)
(signed-unsigned-convertors 16)
(signed-unsigned-convertors 32)
;;(signed-unsigned-convertors 64)