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One-byte-opcodes

X86-pop-general-register

POP: 58+rw/rd

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

Op/En: O

58+rw/rd r16/r32/r64

Note that 58+rd r32 is N.E. in the 64-bit mode and that 58+rd r64 is N.E. in 32-bit mode.

POP does not have a separate instruction semantic function, unlike other opcodes like ADD, SUB, etc. The decoding is coupled with the execution in this case.

Definitions and Theorems

Function: x86-pop-general-register

(defun x86-pop-general-register
       (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-pop-general-register))
  (declare (ignorable __function__))
  (b* ((?ctx 'x86-pop-general-register))
    (b*
      (((the (integer 1 8) operand-size)
        (select-operand-size proc-mode
                             nil rex-byte nil prefixes t t nil x86))
       (rsp (read-*sp proc-mode x86))
       ((mv flg new-rsp)
        (add-to-*sp proc-mode rsp operand-size x86))
       ((when flg)
        (!!fault-fresh :ss 0 :pop flg))
       ((mv flg0 val x86)
        (rme-size-opt proc-mode operand-size rsp
                      2 :r (alignment-checking-enabled-p x86)
                      x86
                      :mem-ptr? nil
                      :check-canonicity t))
       ((when flg0)
        (!!ms-fresh :rme-size-opt flg))
       (reg (logand opcode 7))
       (badlength? (check-instruction-length start-rip temp-rip 0))
       ((when badlength?)
        (!!fault-fresh :gp 0
                       :instruction-length badlength?))
       (x86 (write-*sp proc-mode new-rsp x86))
       (x86 (!rgfi-size operand-size (reg-index reg rex-byte 0)
                        val rex-byte x86))
       (x86 (write-*ip proc-mode temp-rip x86)))
      x86))))

Theorem: x86p-of-x86-pop-general-register

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