softfloat/f128_classify.c

   1
   2 #include <stdbool.h>
   3 #include <stdint.h>
   4 #include "platform.h"
   5 #include "internals.h"
   6 #include "specialize.h"
   7 #include "softfloat.h"
   8
   9 uint_fast16_t f128_classify( float128_t a )
  10 {
  11     union ui128_f128 uA;
  12     uint_fast64_t uiA64, uiA0;
  13
  14     uA.f = a;
  15     uiA64 = uA.ui.v64;
  16     uiA0  = uA.ui.v0;
  17
  18     uint_fast16_t infOrNaN = expF128UI64( uiA64 ) == 0x7FFF;
  19     uint_fast16_t subnormalOrZero = expF128UI64( uiA64 ) == 0;
  20     bool sign = signF128UI64( uiA64 );
  21     bool fracZero = fracF128UI64( uiA64 ) == 0 && uiA0 == 0;
  22     bool isNaN = isNaNF128UI( uiA64, uiA0 );
  23     bool isSNaN = softfloat_isSigNaNF128UI( uiA64, uiA0 );
  24
  25     return
  26         (  sign && infOrNaN && fracZero )          << 0 |
  27         (  sign && !infOrNaN && !subnormalOrZero ) << 1 |
  28         (  sign && subnormalOrZero && !fracZero )  << 2 |
  29         (  sign && subnormalOrZero && fracZero )   << 3 |
  30         ( !sign && infOrNaN && fracZero )          << 7 |
  31         ( !sign && !infOrNaN && !subnormalOrZero ) << 6 |
  32         ( !sign && subnormalOrZero && !fracZero )  << 5 |
  33         ( !sign && subnormalOrZero && fracZero )   << 4 |
  34         ( isNaN &&  isSNaN )                       << 8 |
  35         ( isNaN && !isSNaN )                       << 9;
  36 }
  37