		Search-engine friendly clone of the ACL2 documentation.

Two-byte-opcodes

X86-movbe-op/en-rm

MOVBE: Move data after swapping bytes.

Signature
(x86-movbe-op/en-rm proc-mode start-rip temp-rip prefixes rex-byte opcode modr/m sib x86) → x86
Returns: x86 — Type (x86p x86), given (x86p x86).

This is the variant that moves from memory to register.

Definitions and Theorems

Function: x86-movbe-op/en-rm

(defun x86-movbe-op/en-rm
       (proc-mode start-rip temp-rip
                  prefixes rex-byte opcode modr/m sib x86)
 (declare (xargs :stobjs (x86)))
 (declare (type (integer 0 4) proc-mode)
          (type (signed-byte 48) start-rip)
          (type (signed-byte 48) temp-rip)
          (type (unsigned-byte 52) prefixes)
          (type (unsigned-byte 8) rex-byte)
          (type (unsigned-byte 8) opcode)
          (type (unsigned-byte 8) modr/m)
          (type (unsigned-byte 8) sib))
 (declare (ignorable proc-mode start-rip temp-rip
                     prefixes rex-byte opcode modr/m sib))
 (declare (xargs :guard (and (prefixes-p prefixes)
                             (modr/m-p modr/m)
                             (sib-p sib)
                             (rip-guard-okp proc-mode temp-rip))))
 (let ((__function__ 'x86-movbe-op/en-rm))
  (declare (ignorable __function__))
  (b* ((?ctx 'x86-movbe-op/en-rm)
       (?r/m (the (unsigned-byte 3)
                  (modr/m->r/m modr/m)))
       (?mod (the (unsigned-byte 2)
                  (modr/m->mod modr/m)))
       (?reg (the (unsigned-byte 3)
                  (modr/m->reg modr/m))))
   (b*
    ((p2 (the (unsigned-byte 8)
              (prefixes->seg prefixes)))
     (p4? (equal 103 (prefixes->adr prefixes)))
     ((the (integer 2 8) operand-size)
      (select-operand-size proc-mode nil
                           rex-byte nil prefixes nil nil nil x86))
     (seg-reg
         (select-segment-register proc-mode p2 p4? mod r/m sib x86))
     ((mv flg operand
          (the (unsigned-byte 3) increment-rip-by)
          ?addr x86)
      (x86-operand-from-modr/m-and-sib-bytes
           proc-mode
           0 operand-size t nil seg-reg p4?
           temp-rip rex-byte r/m mod sib 0 x86))
     ((when flg)
      (!!ms-fresh :x86-operand-from-modr/m-and-sib-bytes flg))
     ((mv flg temp-rip)
      (add-to-*ip proc-mode
                  temp-rip increment-rip-by x86))
     ((when flg)
      (!!ms-fresh :rip-increment-error flg))
     (badlength? (check-instruction-length start-rip temp-rip 0))
     ((when badlength?)
      (!!fault-fresh :gp 0
                     :instruction-length badlength?))
     (result (movbe-reverse-bytes operand operand-size))
     (x86 (!rgfi-size operand-size (reg-index reg rex-byte 2)
                      result rex-byte x86))
     (x86 (write-*ip proc-mode temp-rip x86)))
    x86))))

Theorem: x86p-of-x86-movbe-op/en-rm

(defthm x86p-of-x86-movbe-op/en-rm
 (implies
   (x86p x86)
   (b*
     ((x86 (x86-movbe-op/en-rm proc-mode start-rip temp-rip prefixes
                               rex-byte opcode modr/m sib x86)))
     (x86p x86)))
 :rule-classes :rewrite)