Basic equivalence relation for vl-sigma structures.
Function:
(defun vl-sigma-equiv$inline (acl2::x acl2::y) (declare (xargs :guard (and (vl-sigma-p acl2::x) (vl-sigma-p acl2::y)))) (equal (vl-sigma-fix acl2::x) (vl-sigma-fix acl2::y)))
Theorem:
(defthm vl-sigma-equiv-is-an-equivalence (and (booleanp (vl-sigma-equiv x y)) (vl-sigma-equiv x x) (implies (vl-sigma-equiv x y) (vl-sigma-equiv y x)) (implies (and (vl-sigma-equiv x y) (vl-sigma-equiv y z)) (vl-sigma-equiv x z))) :rule-classes (:equivalence))
Theorem:
(defthm vl-sigma-equiv-implies-equal-vl-sigma-fix-1 (implies (vl-sigma-equiv acl2::x x-equiv) (equal (vl-sigma-fix acl2::x) (vl-sigma-fix x-equiv))) :rule-classes (:congruence))
Theorem:
(defthm vl-sigma-fix-under-vl-sigma-equiv (vl-sigma-equiv (vl-sigma-fix acl2::x) acl2::x) :rule-classes (:rewrite :rewrite-quoted-constant))
Theorem:
(defthm equal-of-vl-sigma-fix-1-forward-to-vl-sigma-equiv (implies (equal (vl-sigma-fix acl2::x) acl2::y) (vl-sigma-equiv acl2::x acl2::y)) :rule-classes :forward-chaining)
Theorem:
(defthm equal-of-vl-sigma-fix-2-forward-to-vl-sigma-equiv (implies (equal acl2::x (vl-sigma-fix acl2::y)) (vl-sigma-equiv acl2::x acl2::y)) :rule-classes :forward-chaining)
Theorem:
(defthm vl-sigma-equiv-of-vl-sigma-fix-1-forward (implies (vl-sigma-equiv (vl-sigma-fix acl2::x) acl2::y) (vl-sigma-equiv acl2::x acl2::y)) :rule-classes :forward-chaining)
Theorem:
(defthm vl-sigma-equiv-of-vl-sigma-fix-2-forward (implies (vl-sigma-equiv acl2::x (vl-sigma-fix acl2::y)) (vl-sigma-equiv acl2::x acl2::y)) :rule-classes :forward-chaining)