softfloat/i64_to_f32.c

   1
   2 #include <stdbool.h>
   3 #include <stdint.h>
   4 #include "platform.h"
   5 #include "primitives.h"
   6 #include "internals.h"
   7 #include "softfloat.h"
   8
   9 float32_t i64_to_f32( int_fast64_t a )
  10 {
  11     bool sign;
  12     uint_fast64_t absA;
  13     int shiftCount;
  14     union ui32_f32 u;
  15     uint_fast32_t sig;
  16
  17     sign = ( a < 0 );
  18     absA = sign ? - (uint_fast64_t) a : a;
  19     shiftCount = softfloat_countLeadingZeros64( absA ) - 40;
  20     if ( 0 <= shiftCount ) {
  21         u.ui =
  22             a ? packToF32UI(
  23                     sign, 0x95 - shiftCount, (uint_fast32_t) absA<<shiftCount )
  24                 : 0;
  25         return u.f;
  26     } else {
  27         shiftCount += 7;
  28         sig =
  29             ( shiftCount < 0 )
  30                 ? softfloat_shortShift64RightJam( absA, - shiftCount )
  31                 : (uint_fast32_t) absA<<shiftCount;
  32         return softfloat_roundPackToF32( sign, 0x9C - shiftCount, sig );
  33     }
  34
  35 }
  36