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Two-byte-opcodes

X86-movsx

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

Definitions and Theorems

Function: x86-movsx

(defun x86-movsx (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-movsx))
  (declare (ignorable __function__))
  (b* ((?ctx 'x86-movsx)
       (?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 (prefixes->seg prefixes))
     (p4? (equal 103 (prefixes->adr prefixes)))
     (seg-reg
         (select-segment-register proc-mode p2 p4? mod r/m sib x86))
     (reg/mem-size (if (equal opcode 190) 1 2))
     (inst-ac? t)
     ((mv flg0 reg/mem
          (the (unsigned-byte 3) increment-rip-by)
          (the (signed-byte 64) ?addr)
          x86)
      (x86-operand-from-modr/m-and-sib-bytes
           proc-mode
           0 reg/mem-size inst-ac? nil seg-reg p4?
           temp-rip rex-byte r/m mod sib 0 x86))
     ((when flg0)
      (!!ms-fresh :x86-operand-from-modr/m-and-sib-bytes flg0))
     ((mv flg (the (signed-byte 48) temp-rip))
      (add-to-*ip proc-mode
                  temp-rip increment-rip-by x86))
     ((when flg)
      (!!ms-fresh :rip-increment-error temp-rip))
     (badlength? (check-instruction-length start-rip temp-rip 0))
     ((when badlength?)
      (!!fault-fresh :gp 0
                     :instruction-length badlength?))
     (register-size
        (select-operand-size proc-mode nil
                             rex-byte nil prefixes nil nil nil x86))
     (reg/mem
      (case reg/mem-size
       (1 (mbe :logic (part-select (n08-to-i08 reg/mem)
                                   :low 0
                                   :width (ash register-size 3))
               :exec (logand (1- (ash 1
                                      (the (integer 8 64)
                                           (ash register-size 3))))
                             (n08-to-i08 reg/mem))))
       (2
        (case register-size
         (2 reg/mem)
         (otherwise
           (mbe :logic (part-select (n16-to-i16 reg/mem)
                                    :low 0
                                    :width (ash register-size 3))
                :exec (logand (1- (ash 1
                                       (the (integer 8 64)
                                            (ash register-size 3))))
                              (n16-to-i16 reg/mem))))))))
     (x86 (!rgfi-size register-size (reg-index reg rex-byte 2)
                      reg/mem rex-byte x86))
     (x86 (write-*ip proc-mode temp-rip x86)))
    x86))))

Theorem: x86p-of-x86-movsx

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