Access the |COMMON-LISP|::|TYPE| field of a call-gate-descriptorbits bit structure.
(call-gate-descriptorbits->type x) → type
Function:
(defun call-gate-descriptorbits->type$inline (x) (declare (xargs :guard (call-gate-descriptorbits-p x))) (mbe :logic (let ((x (call-gate-descriptorbits-fix x))) (part-select x :low 40 :width 4)) :exec (the (unsigned-byte 4) (logand (the (unsigned-byte 4) 15) (the (unsigned-byte 88) (ash (the (unsigned-byte 128) x) -40))))))
Theorem:
(defthm 4bits-p-of-call-gate-descriptorbits->type (b* ((type (call-gate-descriptorbits->type$inline x))) (4bits-p type)) :rule-classes :rewrite)
Theorem:
(defthm call-gate-descriptorbits->type$inline-of-call-gate-descriptorbits-fix-x (equal (call-gate-descriptorbits->type$inline (call-gate-descriptorbits-fix x)) (call-gate-descriptorbits->type$inline x)))
Theorem:
(defthm call-gate-descriptorbits->type$inline-call-gate-descriptorbits-equiv-congruence-on-x (implies (call-gate-descriptorbits-equiv x x-equiv) (equal (call-gate-descriptorbits->type$inline x) (call-gate-descriptorbits->type$inline x-equiv))) :rule-classes :congruence)
Theorem:
(defthm call-gate-descriptorbits->type-of-call-gate-descriptorbits (equal (call-gate-descriptorbits->type (call-gate-descriptorbits offset15-0 selector res1 type s dpl p offset31-16 offset63-32 res2 all-zeroes? res3)) (4bits-fix type)))
Theorem:
(defthm call-gate-descriptorbits->type-of-write-with-mask (implies (and (fty::bitstruct-read-over-write-hyps x call-gate-descriptorbits-equiv-under-mask) (call-gate-descriptorbits-equiv-under-mask x y fty::mask) (equal (logand (lognot fty::mask) 16492674416640) 0)) (equal (call-gate-descriptorbits->type x) (call-gate-descriptorbits->type y))))