MOVSX             Move With Sign-Extend (386)        Flags: O D I T S Z A P C

MOVSX destination, source

           Logic:        destination .  sign extend(source)

     This instruction copies a source operand to a destination operand and
     extends its sign. This is particularly useful to preserve signs when
     copying from 8-bit register to a 16-bit one, or a 16-bit register to a
     32-bit one.

     MOVSX is only valid in the 386.

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   Operands                   Clocks   Transfers  Bytes  Example
   MOVSX register, register   3 (386)   1 or 2      3    MOVSX EAX,CX
   MOVSX register, memory     6 (386)   1 or 2      5    MOVSX EAX,MEMLOC
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