New P6 OpCodes: UD2


UD2 -- 0F 0B, 0F B9 -- Undefined Opcode - 2


                                                              UD2
Flags:                                       Undefined Opcode - 2
+-+-+-+-+-+-+-+-+-+                       +----------+----------+
|O|D|I|T|S|Z|A|P|C|                       | 00001111 | 00001011 |
+-+-+-+-+-+-+-+-+-+                       +----------+----------+
| | | | | | | | | |                       |    0F    |    0B    |
+-+-+-+-+-+-+-+-+-+                       +----------+----------+
                                          | 00001111 | 10111001 |
                                          +----------+----------+
                                          |    0F    |    B9    |
                                          +----------+----------+

Operation:

UD2 {
  #UD;
}

Description:

Specifying either opcode 0F 0B, or 0F B9 in an instruction stream will cause an undefined opcode to occur. These two opcodes are unique, in that they will always be available. For applications wishing to intentionally generate an undefined opcode exception, for the purposes of instruction set extensions, they should use either of these defined opcodes.

Example:

    db  0fh,00bh
    db  0fh,0b9h

Flags affected:

None.

Exceptions:

#UD


Get description of        [AAM]        [AAD]        [UMOV]       [LOADALL]
New P6 OpCodes            [CMOV]       [FCMOV]      [FCOMI]      [RDPMC]
                          [INT01]      [SALC]

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