softfloat/bits32/softfloat.c

161 Packs the sign `zSign', exponent `zExp', and significand `zSig' into a
166 will have an integer portion equal to 1, the `zExp' input should be 1 less
171 INLINE float32 packFloat32( flag zSign, int16 zExp, bits32 zSig )
174     return ( ( (bits32) zSign )<<31 ) + ( ( (bits32) zExp )<<23 ) + zSig;
180 Takes an abstract floating-point value having sign `zSign', exponent `zExp',
194 `zExp' must be 0; in that case, the result returned is a subnormal number,
196 normalized, `zExp' must be 1 less than the ``true'' floating-point exponent.
201 static float32 roundAndPackFloat32( flag zSign, int16 zExp, bits32 zSig )
226     if ( 0xFD <= (bits16) zExp ) {
227         if (    ( 0xFD < zExp )
228              || (    ( zExp == 0xFD )
234         if ( zExp < 0 ) {
237                 || ( zExp < -1 )
239             shift32RightJamming( zSig, - zExp, &zSig );
240             zExp = 0;
248     if ( zSig == 0 ) zExp = 0;
249     return packFloat32( zSign, zExp, zSig );
255 Takes an abstract floating-point value having sign `zSign', exponent `zExp',
259 Bit 31 of `zSig' must be zero, and `zExp' must be 1 less than the ``true''
264  normalizeRoundAndPackFloat32( flag zSign, int16 zExp, bits32 zSig )
269     return roundAndPackFloat32( zSign, zExp - shiftCount, zSig<<shiftCount );
367 Packs the sign `zSign', the exponent `zExp', and the significand formed by
370 positions, the three fields `zSign', `zExp', and `zSig0' are simply added
374 the `zExp' input should be 1 less than the desired result exponent whenever
379  packFloat64( flag zSign, int16 zExp, bits32 zSig0, bits32 zSig1 )
383 			   ( ( (bits64) zExp )<<52 ) +
391 Takes an abstract floating-point value having sign `zSign', exponent `zExp',
404 significand is not normalized, `zExp' must be 0; in that case, the result
406 usual case that the input significand is normalized, `zExp' must be 1 less
413      flag zSign, int16 zExp, bits32 zSig0, bits32 zSig1, bits32 zSig2 )
434     if ( 0x7FD <= (bits16) zExp ) {
435         if (    ( 0x7FD < zExp )
436              || (    ( zExp == 0x7FD )
450         if ( zExp < 0 ) {
453                 || ( zExp < -1 )
457                 zSig0, zSig1, zSig2, - zExp, &zSig0, &zSig1, &zSig2 );
458             zExp = 0;
479         if ( ( zSig0 | zSig1 ) == 0 ) zExp = 0;
481     return packFloat64( zSign, zExp, zSig0, zSig1 );
487 Takes an abstract floating-point value having sign `zSign', exponent `zExp',
492 normalized.  In all cases, `zExp' must be 1 less than the ``true'' floating-
498      flag zSign, int16 zExp, bits32 zSig0, bits32 zSig1 )
506         zExp -= 32;
517     zExp -= shiftCount;
518     return roundAndPackFloat64( zSign, zExp, zSig0, zSig1, zSig2 );
790     int16 aExp, bExp, zExp;
813         zExp = aExp;
827         zExp = bExp;
836         zExp = aExp;
841     --zExp;
844         ++zExp;
847     return roundAndPackFloat32( zSign, zExp, zSig );
862     int16 aExp, bExp, zExp;
902     zExp = bExp;
920     zExp = aExp;
922     --zExp;
923     return normalizeRoundAndPackFloat32( zSign, zExp, zSig );
981     int16 aExp, bExp, zExp;
1017     zExp = aExp + bExp - 0x7F;
1024         --zExp;
1026     return roundAndPackFloat32( zSign, zExp, zSig0 );
1040     int16 aExp, bExp, zExp;
1078     zExp = aExp - bExp + 0x7D;
1083         ++zExp;
1095     return roundAndPackFloat32( zSign, zExp, zSig );
1197     int16 aExp, zExp;
1218     zExp = ( ( aExp - 0x7F )>>1 ) + 0x7E;
1241     return roundAndPackFloat32( 0, zExp, zSig );
1669     int16 aExp, bExp, zExp;
1693         zExp = aExp;
1708         zExp = bExp;
1721         zExp = aExp;
1726     --zExp;
1728     ++zExp;
1732     return roundAndPackFloat64( zSign, zExp, zSig0, zSig1, zSig2 );
1747     int16 aExp, bExp, zExp;
1793     zExp = bExp;
1811     zExp = aExp;
1813     --zExp;
1814     return normalizeRoundAndPackFloat64( zSign, zExp - 10, zSig0, zSig1 );
1872     int16 aExp, bExp, zExp;
1909     zExp = aExp + bExp - 0x400;
1918         ++zExp;
1920     return roundAndPackFloat64( zSign, zExp, zSig0, zSig1, zSig2 );
1934     int16 aExp, bExp, zExp;
1975     zExp = aExp - bExp + 0x3FD;
1980         ++zExp;
2000     return roundAndPackFloat64( zSign, zExp, zSig0, zSig1, zSig2 );
2120     int16 aExp, zExp;
2144     zExp = ( ( aExp - 0x3FF )>>1 ) + 0x3FE;
2175     return roundAndPackFloat64( 0, zExp, zSig0, zSig1, zSig2 );