i386/i386.reference/INC.htm

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   4 <TITLE>80386 Programmer's Reference Manual -- Opcode INC</TITLE>
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   8 Chapter 17 -- 80386 Instruction Set</A><BR>
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  13 <P>
  14 <H1>INC -- Increment by 1</H1>
  15
  16 <PRE>
  17 Opcode      Instruction        Clocks      Description
  18
  19 FE  /0      INC r/m8                       Increment r/m byte by 1
  20 FF  /0      INC r/m16                      Increment r/m word by 1
  21 FF  /6      INC r/m32                      Increment r/m dword by 1
  22 40 + rw     INC r16                        Increment word register by 1
  23 40 + rd     INC r32                        Increment dword register by 1
  24 </PRE>
  25
  26 <H2>Operation</H2>
  27
  28 <PRE>
  29 DEST := DEST + 1;
  30 </PRE>
  31
  32 <H2>Description</H2>
  33
  34 INC adds 1 to the operand. It does not change the carry flag. To affect
  35 the carry flag, use the
  36 <A HREF="ADD.htm">ADD</A> instruction with a second operand of 1.
  37
  38 <H2>Flags Affected</H2>
  39
  40 OF, SF, ZF, AF, and PF as described in <A HREF="appc.htm">Appendix C</A>
  41
  42 <H2>Protected Mode Exceptions</H2>
  43
  44 #GP(0) if the operand is in a nonwritable segment; #GP(0) for an illegal
  45 memory operand effective address in the CS, DS, ES, FS, or GS
  46 segments; #SS(0) for an illegal address in the SS segment; #PF(fault-code)
  47 for a page fault
  48
  49 <H2>Real Address Mode Exceptions</H2>
  50
  51 Interrupt 13 if any part of the operand would lie outside of the effective
  52 address space from 0 to 0FFFFH
  53
  54 <H2>Virtual 8086 Mode Exceptions</H2>
  55
  56 Same exceptions as in Real Address Mode; #PF(fault-code) for a page
  57 fault
  58
  59
  60 <P>
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  63 <B>up:</B> <A HREF="c17.htm">
  64 Chapter 17 -- 80386 Instruction Set</A><BR>
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  66 <B>next:</B><A HREF="INS.htm"> INS/INSB/INSW/INSD Input from Port to String</A>
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