		Search-engine friendly clone of the ACL2 documentation.

One-byte-opcodes

X86-cmc/clc/stc/cld/std

Signature
(x86-cmc/clc/stc/cld/std 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-cmc/clc/stc/cld/std

(defun x86-cmc/clc/stc/cld/std
       (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-cmc/clc/stc/cld/std))
  (declare (ignorable __function__))
  (b* ((?ctx 'x86-cmc/clc/stc/cld/std))
    (b*
     ((x86 (case opcode
             (245 (let* ((cf (the (unsigned-byte 1) (flgi :cf x86)))
                         (not-cf (if (equal cf 1) 0 1)))
                    (!flgi :cf not-cf x86)))
             (248 (!flgi :cf 0 x86))
             (249 (!flgi :cf 1 x86))
             (252 (!flgi :df 0 x86))
             (otherwise (!flgi :df 1 x86))))
      (x86 (write-*ip proc-mode temp-rip x86)))
     x86))))

Theorem: x86p-of-x86-cmc/clc/stc/cld/std

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