Fixing function for truth-idx bit structures.
(truth-idx-fix x) → fty::fixed
Function:
(defun truth-idx-fix (x) (declare (xargs :guard (truth-idx-p x))) (let ((__function__ 'truth-idx-fix)) (declare (ignorable __function__)) (mbe :logic (loghead 16 x) :exec x)))
Theorem:
(defthm truth-idx-p-of-truth-idx-fix (b* ((fty::fixed (truth-idx-fix x))) (truth-idx-p fty::fixed)) :rule-classes :rewrite)
Theorem:
(defthm truth-idx-fix-when-truth-idx-p (implies (truth-idx-p x) (equal (truth-idx-fix x) x)))
Function:
(defun truth-idx-equiv$inline (acl2::x acl2::y) (declare (xargs :guard (and (truth-idx-p acl2::x) (truth-idx-p acl2::y)))) (equal (truth-idx-fix acl2::x) (truth-idx-fix acl2::y)))
Theorem:
(defthm truth-idx-equiv-is-an-equivalence (and (booleanp (truth-idx-equiv x y)) (truth-idx-equiv x x) (implies (truth-idx-equiv x y) (truth-idx-equiv y x)) (implies (and (truth-idx-equiv x y) (truth-idx-equiv y z)) (truth-idx-equiv x z))) :rule-classes (:equivalence))
Theorem:
(defthm truth-idx-equiv-implies-equal-truth-idx-fix-1 (implies (truth-idx-equiv acl2::x x-equiv) (equal (truth-idx-fix acl2::x) (truth-idx-fix x-equiv))) :rule-classes (:congruence))
Theorem:
(defthm truth-idx-fix-under-truth-idx-equiv (truth-idx-equiv (truth-idx-fix acl2::x) acl2::x) :rule-classes (:rewrite :rewrite-quoted-constant))
Theorem:
(defthm truth-idx-fix-of-truth-idx-fix-x (equal (truth-idx-fix (truth-idx-fix x)) (truth-idx-fix x)))
Theorem:
(defthm truth-idx-fix-truth-idx-equiv-congruence-on-x (implies (truth-idx-equiv x x-equiv) (equal (truth-idx-fix x) (truth-idx-fix x-equiv))) :rule-classes :congruence)