hw/i386.reference/appd.htm

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   4 <TITLE>80386 Programmer's Reference Manual -- Appendix D</TITLE>
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  14 <H1>Appendix D -- Condition Codes</H1>
  15
  16 <EM>
  17 <H3>Note</H3>
  18   The terms "above" and "below" refer to the relation between two
  19   unsigned values (neither SF nor OF is tested). The terms "greater" and
  20   "less" refer to the relation between two signed values (SF and OF are
  21   tested).
  22 </EM>
  23
  24 <H3>Definition of Conditions</H3>
  25
  26 (For conditional instructions Jcond, and SETcond)
  27
  28 <PRE>
  29                                        Instruction  Condition
  30 Mnemonic  Meaning                      Subcode      Tested
  31
  32 O         Overflow                     0000         OF = 1
  33
  34 NO        No overflow                  0001         OF = 0
  35
  36 B         Below
  37 NAE       Neither above nor equal      0010         CF = 1
  38
  39 NB        Not below
  40 AE       Above or equal                0011         CF = 0
  41
  42 E         Equal
  43 Z         Zero                         0100         ZF = 1
  44
  45 NE        Not equal
  46 NZ        Not zero                     0101         ZF = 0
  47
  48 BE        Below or equal
  49 NA        Not above                    0110         (CF or ZF) = 1
  50
  51 NBE       Neither below nor equal
  52 NA        Above                        0111         (CF or ZF) = 0
  53
  54 S         Sign                         1000         SF = 1
  55
  56 NS        No sign                      1001         SF = 0
  57
  58 P         Parity
  59 PE        Parity even                  1010         PF = 1
  60
  61 NP        No parity
  62 PO        Parity odd                   1011         PF = 0
  63
  64 L         Less
  65 NGE       Neither greater nor equal    1100         (SF xor OF) = 1
  66
  67 NL        Not less
  68 GE        Greater or equal             1101         (SF xor OF) = 0
  69
  70 LE        Less or equal
  71 NG        Not greater                  1110         ((SF xor OF) or ZF) = 1
  72
  73 NLE       Neither less nor equal
  74 G         Greater                      1111         ((SF xor OF) or ZF) = 0
  75 </PRE>
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