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• Sbyte256

Sbyte256-fix

Fixer for sbyte256.

Signature

(sbyte256-fix x) → fixed-x

Arguments

x — Guard (sbyte256p x).

Returns

fixed-x — Type (sbyte256p fixed-x).

Definitions and Theorems

Function: sbyte256-fix

(defun sbyte256-fix (x)
  (declare (xargs :guard (sbyte256p x)))
  (mbe :logic (if (sbyte256p x) x 0)
       :exec x))

Theorem: sbyte256p-of-sbyte256-fix

(defthm sbyte256p-of-sbyte256-fix
  (b* ((fixed-x (sbyte256-fix x)))
    (sbyte256p fixed-x))
  :rule-classes :rewrite)

Theorem: sbyte256-fix-when-sbyte256p

(defthm sbyte256-fix-when-sbyte256p
  (implies (sbyte256p x)
           (equal (sbyte256-fix x) x)))