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#include <stdbool.h>
#include <stdint.h>
#include "platform.h"
#include "primitives.h"
#include "internals.h"
#include "softfloat.h"
float32_t
softfloat_roundPackToF32( bool sign, int_fast16_t exp, uint_fast32_t sig )
{
int roundingMode;
bool roundNearestEven;
int roundIncrement, roundBits;
bool isTiny;
uint_fast32_t uiZ;
union ui32_f32 uZ;
roundingMode = softfloat_roundingMode;
roundNearestEven = ( roundingMode == softfloat_round_nearest_even );
roundIncrement = 0x40;
if (
! roundNearestEven
&& ( roundingMode != softfloat_round_nearest_maxMag )
) {
roundIncrement =
( roundingMode == softfloat_round_minMag )
|| ( roundingMode
== ( sign ? softfloat_round_max : softfloat_round_min ) )
? 0
: 0x7F;
}
roundBits = sig & 0x7F;
if ( 0xFD <= (uint16_t) exp ) {
if ( exp < 0 ) {
isTiny =
( softfloat_detectTininess
== softfloat_tininess_beforeRounding )
|| ( exp < -1 )
|| ( sig + roundIncrement < 0x80000000 );
sig = softfloat_shift32RightJam( sig, - exp );
exp = 0;
roundBits = sig & 0x7F;
if ( isTiny && roundBits ) {
softfloat_raiseFlags( softfloat_flag_underflow );
}
} else if (
( 0xFD < exp ) || ( 0x80000000 <= sig + roundIncrement )
) {
softfloat_raiseFlags(
softfloat_flag_overflow | softfloat_flag_inexact );
uiZ = packToF32UI( sign, 0xFF, 0 ) - ! roundIncrement;
goto uiZ;
}
}
if ( roundBits ) softfloat_exceptionFlags |= softfloat_flag_inexact;
sig = ( sig + roundIncrement )>>7;
sig &= ~ ( ! ( roundBits ^ 0x40 ) & roundNearestEven );
uiZ = packToF32UI( sign, sig ? exp : 0, sig );
uiZ:
uZ.ui = uiZ;
return uZ.f;
}
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