i386/i386.reference/SLDT.htm

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   4 <TITLE>80386 Programmer's Reference Manual -- Opcode SLDT</TITLE>
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   8 Chapter 17 -- 80386 Instruction Set</A><BR>
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  13 <P>
  14 <H1>SLDT -- Store Local Descriptor Table Register</H1>
  15
  16 <PRE>
  17 Opcode      Instruction   Clocks      Description
  18
  19 0F  00 /0   SLDT r/m16    pm=2/2      Store LDTR to EA word
  20 </PRE>
  21
  22 <H2>Operation</H2>
  23
  24 <PRE>
  25 r/m16 := LDTR;
  26 </PRE>
  27
  28 <H2>Description</H2>
  29
  30 SLDT stores the Local Descriptor Table Register (LDTR) in the two-byte
  31 register or memory location indicated by the effective address operand.
  32 This register is a selector that points into the Global Descriptor Table.
  33 <P>
  34 SLDT is used only in operating system software. It is not used in
  35 application programs.
  36
  37 <H2>Flags Affected</H2>
  38
  39 None
  40
  41 <H2>Protected Mode Exceptions</H2>
  42
  43 #GP(0) if the result is in a nonwritable segment; #GP(0) for an illegal
  44 memory operand effective address in the CS, DS, ES, FS, or GS segments;
  45 #SS(0) for an illegal address in the SS segment; #PF(fault-code) for a page
  46 fault
  47
  48 <H2>Real Address Mode Exceptions</H2>
  49
  50 Interrupt 6; SLDT is not recognized in Real Address Mode
  51
  52 <H2>Virtual 8086 Mode Exceptions</H2>
  53
  54 Same exceptions as in Real Address Mode; #PF(fault-code) for a page fault
  55
  56 <H2>Notes</H2>
  57
  58 The operand-size attribute has no effect on the operation of the
  59 instruction.
  60
  61
  62 <P>
  63 <HR>
  64 <P>
  65 <B>up:</B> <A HREF="c17.htm">
  66 Chapter 17 -- 80386 Instruction Set</A><BR>
  67 <B>prev:</B><A HREF="SHRD.htm"> SHRD Double Precision Shift Right</A><BR>
  68 <B>next:</B><A HREF="SMSW.htm"> SMSW Store Machine Status Word</A>
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