ttl       ieee format equivalent float to integer (ieffpi)
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* (c) copyright 1981 by motorla inc. *
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*    ieffpi - ieee format equivalent float to integer     *
*                                                         *
*      input:  d7 = ieee format number                    *
*      output: d7 = fixed point longword integer          *
*                            (2's complement)             *
*                                                         *
*  condition codes:                                       *
*             n - set if result is negative               *
*             z - set if result is zero                   *
*             v - set if result overflowed integer        *
*                 representation or input was a nan       *
*                 (not-a-number)                          *
*             c - undefined                               *
*             x - undefined                               *
*                                                         *
*     registers are transparent over this routine         *
*                                                         *
*              stack used:    54 bytes                    *
*                                                         *
*  the range provided with 2's complement longword binary *
*  is:   -2,147,483,649 < value < +2,147,483,648          *
*                                                         *
*  notes:                                                 *
*   1) since ieee single precision format holds 24 bits   *
*      of precision which is less than the 31 bits of     *
*      longword binary integer arithmetic, results of     *
*      over 24 bit integer magnitude will be imprecise    *
*      and have low-end zeroes.                           *
*   2) if the input argument is too large to be contained *
*      in the longword fixed point binary format, the     *
*      largest possible magnitude value is returned with  *
*      the "v" bit set in the condition code register.    *
*   3) if a nan (not-a-number) is the input argument,     *
*      it will be returned as is with the "v" bit set.    *
*   4) since the "v" bit is set for two possible          *
*      conditions (overflow or nan) they can be separated *
*      by testing the significand (bits 0 thru 22).  if   *
*      these bits are all ones, then the value probably   *
*      was an overflow.  any other pattern indicates the  *
*      input argument was nan.                            *
*                                                         *
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         page
         xdef      ieffpi    entry point
 
        xref      ffpfpi    fast floating point float to integer
        xref      ffpfieee  ffp conversion of ieee to ffp format
        xref      iefsop    ieee single operand convert internal routine
        xref      ffpcpyrt  copyright notice
 
ieffpi  idnt      1,1  ieee format equivalent float to integer
 
        section    9
 
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* ieee float to integer *
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ieffpi   bsr       iefsop    convert to fast floating point or reject nan
         bra.s     iefnrm    +0 normalized value, denormalized value or zero
*                                       +2 argument infinity
 
* infinity - convert to ffp format's largest magnitude
         bsr       ffpfieee  ffp's conversion will force to highest possible
 
* normalized value, denormalized or zero
iefnrm   bsr       ffpfpi    convert from fast floating point to integer
         movem.l   (sp)+,d3-d6 reload callers registers
         add.l     #4,sp     skip original argument
         rts                 return to caller with integer in d7 and ccr set
 
         end