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Evex-byte1

Evex-byte1->r

Access the |ACL2|::|R| field of a evex-byte1 bit structure.

Signature
(evex-byte1->r byte1) → r
Arguments: byte1 — Guard (evex-byte1-p byte1).
Returns: r — Type (bitp r).

Definitions and Theorems

Function: evex-byte1->r$inline

(defun evex-byte1->r$inline (byte1)
  (declare (xargs :guard (evex-byte1-p byte1)))
  (mbe :logic
       (let ((byte1 (evex-byte1-fix byte1)))
         (part-select byte1 :low 7 :width 1))
       :exec (the (unsigned-byte 1)
                  (logand (the (unsigned-byte 1) 1)
                          (the (unsigned-byte 1)
                               (ash (the (unsigned-byte 8) byte1)
                                    -7))))))

Theorem: bitp-of-evex-byte1->r

(defthm bitp-of-evex-byte1->r
  (b* ((r (evex-byte1->r$inline byte1)))
    (bitp r))
  :rule-classes :rewrite)

Theorem: evex-byte1->r$inline-of-evex-byte1-fix-byte1

(defthm evex-byte1->r$inline-of-evex-byte1-fix-byte1
  (equal (evex-byte1->r$inline (evex-byte1-fix byte1))
         (evex-byte1->r$inline byte1)))

Theorem: evex-byte1->r$inline-evex-byte1-equiv-congruence-on-byte1

(defthm evex-byte1->r$inline-evex-byte1-equiv-congruence-on-byte1
  (implies (evex-byte1-equiv byte1 byte1-equiv)
           (equal (evex-byte1->r$inline byte1)
                  (evex-byte1->r$inline byte1-equiv)))
  :rule-classes :congruence)

Theorem: evex-byte1->r-of-evex-byte1

(defthm evex-byte1->r-of-evex-byte1
  (equal (evex-byte1->r (evex-byte1 mmm res r-prime b x r))
         (bfix r)))

Theorem: evex-byte1->r-of-write-with-mask

(defthm evex-byte1->r-of-write-with-mask
  (implies (and (fty::bitstruct-read-over-write-hyps
                     byte1 evex-byte1-equiv-under-mask)
                (evex-byte1-equiv-under-mask byte1 y fty::mask)
                (equal (logand (lognot fty::mask) 128)
                       0))
           (equal (evex-byte1->r byte1)
                  (evex-byte1->r y))))