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FDIV            Divide real                          Exceptions: I D Z O U P
FDIVP           Divide real and pop                  C3 C2 C1 C0: ? ? * ?

FDIV [[destination,] source]
FDIVP [destination, ST]

        Logic   ; FDIV source                   ; FDIV and FDIVP
                ST . ST / source                ST(1) . ST(1) / ST
                                                pop ST

                ; FDIV dest, source             ; FDIVP dest, ST
                ST(dest) . ST(dest) / ST(src)   ST(dest) . ST(dest) / ST
                                                pop ST

    FDIV/FDIVP divide the destination operand by the source operand and
    leave the quotient in the destination operand.

    The one-operand form of FDIV divides ST by a (single or double real)
    memory operand and leaves the result in ST.
    The two-operand form of FDIV divides two register operands (one of
    these must be ST) and stores the result in the destination register.
    FDIVP works like the two-operand FDIV but requires ST to be the
    source operand; it also pops the stack.
    The no-operand forms FDIV and FDIVP equal 'FDIVP ST(1), ST'.


    Opcode      Format
    D8 /6       FDIV m32
    DC /6       FDIV m64
    D8 F0 + i   FDIV ST,ST(i)
    DC F8 + i   FDIV ST(i),ST
    DE F8 + i   FDIVP ST(i),ST
    DE F9       FDIV
    DE F9       FDIVP


    Timing
    Variations/
    operand       8087         287        387      486     Pentium
    fdiv reg    193-203      193-203     88-91     73      39      FX
    fdiv m32   (215-225)+EA  215-225      89       73      39      FX
    fdiv m64   (220-230)+EA  220-230      94       73      39      FX
    fdivp       197-207      197-207      91       73      39      FX