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