softfloat/f32_div.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 float32_t f32_div( float32_t a, float32_t b )
  10 {
  11     union ui32_f32 uA;
  12     uint_fast32_t uiA;
  13     bool signA;
  14     int_fast16_t expA;
  15     uint_fast32_t sigA;
  16     union ui32_f32 uB;
  17     uint_fast32_t uiB;
  18     bool signB;
  19     int_fast16_t expB;
  20     uint_fast32_t sigB;
  21     bool signZ;
  22     struct exp16_sig32 normExpSig;
  23     int_fast16_t expZ;
  24     uint_fast32_t sigZ;
  25     uint_fast32_t uiZ;
  26     union ui32_f32 uZ;
  27
  28     uA.f = a;
  29     uiA = uA.ui;
  30     signA = signF32UI( uiA );
  31     expA = expF32UI( uiA );
  32     sigA = fracF32UI( uiA );
  33     uB.f = b;
  34     uiB = uB.ui;
  35     signB = signF32UI( uiB );
  36     expB = expF32UI( uiB );
  37     sigB = fracF32UI( uiB );
  38     signZ = signA ^ signB;
  39     if ( expA == 0xFF ) {
  40         if ( sigA ) goto propagateNaN;
  41         if ( expB == 0xFF ) {
  42             if ( sigB ) goto propagateNaN;
  43             goto invalid;
  44         }
  45         goto infinity;
  46     }
  47     if ( expB == 0xFF ) {
  48         if ( sigB ) goto propagateNaN;
  49         goto zero;
  50     }
  51     if ( ! expB ) {
  52         if ( ! sigB ) {
  53             if ( ! ( expA | sigA ) ) goto invalid;
  54             softfloat_raiseFlags( softfloat_flag_infinity );
  55             goto infinity;
  56         }
  57         normExpSig = softfloat_normSubnormalF32Sig( sigB );
  58         expB = normExpSig.exp;
  59         sigB = normExpSig.sig;
  60     }
  61     if ( ! expA ) {
  62         if ( ! sigA ) goto zero;
  63         normExpSig = softfloat_normSubnormalF32Sig( sigA );
  64         expA = normExpSig.exp;
  65         sigA = normExpSig.sig;
  66     }
  67     expZ = expA - expB + 0x7D;
  68     sigA = ( sigA | 0x00800000 )<<7;
  69     sigB = ( sigB | 0x00800000 )<<8;
  70     if ( sigB <= ( sigA + sigA ) ) {
  71         ++expZ;
  72         sigA >>= 1;
  73     }
  74     sigZ = ( (uint_fast64_t) sigA<<32 ) / sigB;
  75     if ( ! ( sigZ & 0x3F ) ) {
  76         sigZ |= ( (uint_fast64_t) sigB * sigZ != (uint_fast64_t) sigA<<32 );
  77     }
  78     return softfloat_roundPackToF32( signZ, expZ, sigZ );
  79  propagateNaN:
  80     uiZ = softfloat_propagateNaNF32UI( uiA, uiB );
  81     goto uiZ;
  82  invalid:
  83     softfloat_raiseFlags( softfloat_flag_invalid );
  84     uiZ = defaultNaNF32UI;
  85     goto uiZ;
  86  infinity:
  87     uiZ = packToF32UI( signZ, 0xFF, 0 );
  88     goto uiZ;
  89  zero:
  90     uiZ = packToF32UI( signZ, 0, 0 );
  91  uiZ:
  92     uZ.ui = uiZ;
  93     return uZ.f;
  94
  95 }
  96