softfloat/f32_to_ui64_r_minMag.c

   1
   2 #include <stdbool.h>
   3 #include <stdint.h>
   4 #include "platform.h"
   5 #include "internals.h"
   6 #include "softfloat.h"
   7
   8 uint_fast64_t f32_to_ui64_r_minMag( float32_t a, bool exact )
   9 {
  10     union ui32_f32 uA;
  11     uint_fast32_t uiA;
  12     int_fast16_t exp;
  13     uint_fast32_t sig;
  14     int_fast16_t shiftCount;
  15     uint_fast64_t sig64, z;
  16
  17     uA.f = a;
  18     uiA = uA.ui;
  19     exp = expF32UI( uiA );
  20     sig = fracF32UI( uiA );
  21     if ( exp < 0x7F ) {
  22         if ( exact && ( exp | sig ) ) {
  23             softfloat_exceptionFlags |= softfloat_flag_inexact;
  24         }
  25         return 0;
  26     }
  27     if ( signF32UI( uiA ) ) goto invalid;
  28     shiftCount = 0xBE - exp;
  29     if ( shiftCount < 0 ) goto invalid;
  30     sig |= 0x00800000;
  31     sig64 = (uint_fast64_t) sig<<40;
  32     z = sig64>>shiftCount;
  33     shiftCount = 40 - shiftCount;
  34     if (
  35         exact && ( shiftCount < 0 ) && (uint32_t) ( sig<<( shiftCount & 31 ) )
  36     ) {
  37         softfloat_exceptionFlags |= softfloat_flag_inexact;
  38     }
  39     return z;
  40  invalid:
  41     softfloat_raiseFlags( softfloat_flag_invalid );
  42     return UINT64_C( 0xFFFFFFFFFFFFFFFF );
  43
  44 }
  45