		Search-engine friendly clone of the ACL2 documentation.

Rflag-specifications

Add-af-spec32

Signature
(add-af-spec32 dst src) → *

Definitions and Theorems

Function: add-af-spec32$inline

(defun add-af-spec32$inline (dst src)
  (declare (type (unsigned-byte 32) dst)
           (type (unsigned-byte 32) src))
  (b* (((the (unsigned-byte 4) dst-3-0)
        (mbe :logic (part-select dst :low 0 :width 4)
             :exec (logand 15 dst)))
       ((the (unsigned-byte 4) src-3-0)
        (mbe :logic (part-select src :low 0 :width 4)
             :exec (logand 15 src)))
       (add (the (unsigned-byte 5)
                 (+ (the (unsigned-byte 4) dst-3-0)
                    (the (unsigned-byte 4) src-3-0))))
       (af (the (unsigned-byte 1)
                (bool->bit (< 15 add)))))
    af))

Theorem: n01p-add-af-spec32

(defthm n01p-add-af-spec32
 (unsigned-byte-p 1 (add-af-spec32 dst src))
 :rule-classes
 (:rewrite
  (:type-prescription
      :corollary (natp (add-af-spec32 dst src))
      :hints
      (("Goal" :in-theory '(unsigned-byte-p integer-range-p natp))))
  (:linear
   :corollary (and (<= 0 (add-af-spec32 dst src))
                   (< (add-af-spec32 dst src) 2))
   :hints
   (("Goal"
        :in-theory '(unsigned-byte-p integer-range-p (:e expt)))))))