Access the |X86ISA|::|UNKNOWNBITS| field of a call-gate-descriptor-attributesbits bit structure.
(call-gate-descriptor-attributesbits->unknownbits x) → unknownbits
Function:
(defun call-gate-descriptor-attributesbits->unknownbits$inline (x) (declare (xargs :guard (call-gate-descriptor-attributesbits-p x))) (mbe :logic (let ((x (call-gate-descriptor-attributesbits-fix x))) (part-select x :low 8 :width 8)) :exec (the (unsigned-byte 8) (logand (the (unsigned-byte 8) 255) (the (unsigned-byte 8) (ash (the (unsigned-byte 16) x) -8))))))
Theorem:
(defthm 8bits-p-of-call-gate-descriptor-attributesbits->unknownbits (b* ((unknownbits (call-gate-descriptor-attributesbits->unknownbits$inline x))) (8bits-p unknownbits)) :rule-classes :rewrite)
Theorem:
(defthm call-gate-descriptor-attributesbits->unknownbits$inline-of-call-gate-descriptor-attributesbits-fix-x (equal (call-gate-descriptor-attributesbits->unknownbits$inline (call-gate-descriptor-attributesbits-fix x)) (call-gate-descriptor-attributesbits->unknownbits$inline x)))
Theorem:
(defthm call-gate-descriptor-attributesbits->unknownbits$inline-call-gate-descriptor-attributesbits-equiv-congruence-on-x (implies (call-gate-descriptor-attributesbits-equiv x x-equiv) (equal (call-gate-descriptor-attributesbits->unknownbits$inline x) (call-gate-descriptor-attributesbits->unknownbits$inline x-equiv))) :rule-classes :congruence)
Theorem:
(defthm call-gate-descriptor-attributesbits->unknownbits-of-call-gate-descriptor-attributesbits (equal (call-gate-descriptor-attributesbits->unknownbits (call-gate-descriptor-attributesbits type s dpl p unknownbits)) (8bits-fix unknownbits)))
Theorem:
(defthm call-gate-descriptor-attributesbits->unknownbits-of-write-with-mask (implies (and (fty::bitstruct-read-over-write-hyps x call-gate-descriptor-attributesbits-equiv-under-mask) (call-gate-descriptor-attributesbits-equiv-under-mask x y fty::mask) (equal (logand (lognot fty::mask) 65280) 0)) (equal (call-gate-descriptor-attributesbits->unknownbits x) (call-gate-descriptor-attributesbits->unknownbits y))))