i386/i386.reference/LAHF.htm

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   4 <TITLE>80386 Programmer's Reference Manual -- Opcode LAHF</TITLE>
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   7 <B>up:</B> <A HREF="c17.htm">
   8 Chapter 17 -- 80386 Instruction Set</A><BR>
   9 <B>prev:</B><A HREF="JMP.htm"> JMP Jump</A><BR>
  10 <B>next:</B><A HREF="LAR.htm"> LAR Load Access Rights Byte</A>
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  13 <P>
  14 <H1>LAHF -- Load Flags into AH Register</H1>
  15
  16 <PRE>
  17 Opcode  Instruction   Clocks   Description
  18
  19 9F      LAHF          2        Load: AH := flags SF ZF xx AF xx PF xx CF
  20 </PRE>
  21
  22 <H2>Operation</H2>
  23
  24 <PRE>
  25 AH := SF:ZF:xx:AF:xx:PF:xx:CF;
  26 </PRE>
  27
  28 <H2>Description</H2>
  29
  30 LAHF transfers the low byte of the flags word to AH. The bits, from
  31 MSB to LSB, are sign, zero, indeterminate, auxiliary, carry,
  32 indeterminate, parity, indeterminate, and carry.
  33
  34 <H2>Flags Affected</H2>
  35
  36 None
  37
  38 <H2>Protected Mode Exceptions</H2>
  39
  40 None
  41
  42 <H2>Real Address Mode Exceptions</H2>
  43
  44 None
  45
  46 <H2>Virtual 8086 Mode Exceptions</H2>
  47
  48 None
  49
  50
  51 <P>
  52 <HR>
  53 <P>
  54 <B>up:</B> <A HREF="c17.htm">
  55 Chapter 17 -- 80386 Instruction Set</A><BR>
  56 <B>prev:</B><A HREF="JMP.htm"> JMP Jump</A><BR>
  57 <B>next:</B><A HREF="LAR.htm"> LAR Load Access Rights Byte</A>
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