+/*============================================================================
+
+This C source file is part of the SoftFloat IEEE Floating-Point Arithmetic
+Package, Release 3d, by John R. Hauser.
+
+Copyright 2011, 2012, 2013, 2014, 2017 The Regents of the University of
+California. All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:
+
+ 1. Redistributions of source code must retain the above copyright notice,
+ this list of conditions, and the following disclaimer.
+
+ 2. Redistributions in binary form must reproduce the above copyright notice,
+ this list of conditions, and the following disclaimer in the documentation
+ and/or other materials provided with the distribution.
+
+ 3. Neither the name of the University nor the names of its contributors may
+ be used to endorse or promote products derived from this software without
+ specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS "AS IS", AND ANY
+EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE, ARE
+DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE FOR ANY
+DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+=============================================================================*/
+
#include <stdbool.h>
#include <stdint.h>
#include "platform.h"
#include "specialize.h"
#include "softfloat.h"
-float32_t f32_roundToInt( float32_t a, int_fast8_t roundingMode, bool exact )
+float32_t f32_roundToInt( float32_t a, uint_fast8_t roundingMode, bool exact )
{
union ui32_f32 uA;
uint_fast32_t uiA;
- int_fast16_t expA;
- uint_fast32_t uiZ;
- bool signA;
- uint_fast32_t lastBitMask, roundBitsMask;
+ int_fast16_t exp;
+ uint_fast32_t uiZ, lastBitMask, roundBitsMask;
union ui32_f32 uZ;
+ /*------------------------------------------------------------------------
+ *------------------------------------------------------------------------*/
uA.f = a;
uiA = uA.ui;
- expA = expF32UI( uiA );
- if ( 0x96 <= expA ) {
- if ( ( expA == 0xFF ) && fracF32UI( uiA ) ) {
- uiZ = softfloat_propagateNaNF32UI( uiA, 0 );
- goto uiZ;
- }
- return a;
- }
- if ( expA <= 0x7E ) {
- if ( ! (uint32_t) ( uiA<<1 ) ) return a;
+ exp = expF32UI( uiA );
+ /*------------------------------------------------------------------------
+ *------------------------------------------------------------------------*/
+ if ( exp <= 0x7E ) {
+ if ( ! (uint32_t) (uiA<<1) ) return a;
if ( exact ) softfloat_exceptionFlags |= softfloat_flag_inexact;
- signA = signF32UI( uiA );
+ uiZ = uiA & packToF32UI( 1, 0, 0 );
switch ( roundingMode ) {
- case softfloat_round_nearest_even:
- if ( ( expA == 0x7E ) && fracF32UI( uiA ) ) {
- uiZ = packToF32UI( signA, 0x7F, 0 );
- goto uiZ;
- }
+ case softfloat_round_near_even:
+ if ( ! fracF32UI( uiA ) ) break;
+ case softfloat_round_near_maxMag:
+ if ( exp == 0x7E ) uiZ |= packToF32UI( 0, 0x7F, 0 );
break;
case softfloat_round_min:
- uiZ = signA ? 0xBF800000 : 0;
- goto uiZ;
+ if ( uiZ ) uiZ = packToF32UI( 1, 0x7F, 0 );
+ break;
case softfloat_round_max:
- uiZ = signA ? 0x80000000 : 0x3F800000;
- goto uiZ;
- case softfloat_round_nearest_maxMag:
- if ( expA == 0x7E ) {
- uiZ = packToF32UI( signA, 0x7F, 0 );
- goto uiZ;
- }
+ if ( ! uiZ ) uiZ = packToF32UI( 0, 0x7F, 0 );
break;
}
- uiZ = packToF32UI( signA, 0, 0 );
goto uiZ;
}
- lastBitMask = (uint_fast32_t) 1<<( 0x96 - expA );
- roundBitsMask = lastBitMask - 1;
+ /*------------------------------------------------------------------------
+ *------------------------------------------------------------------------*/
+ if ( 0x96 <= exp ) {
+ if ( (exp == 0xFF) && fracF32UI( uiA ) ) {
+ uiZ = softfloat_propagateNaNF32UI( uiA, 0 );
+ goto uiZ;
+ }
+ return a;
+ }
+ /*------------------------------------------------------------------------
+ *------------------------------------------------------------------------*/
uiZ = uiA;
- if ( roundingMode == softfloat_round_nearest_maxMag ) {
+ lastBitMask = (uint_fast32_t) 1<<(0x96 - exp);
+ roundBitsMask = lastBitMask - 1;
+ if ( roundingMode == softfloat_round_near_maxMag ) {
uiZ += lastBitMask>>1;
- } else if ( roundingMode == softfloat_round_nearest_even ) {
+ } else if ( roundingMode == softfloat_round_near_even ) {
uiZ += lastBitMask>>1;
- if ( ! ( uiZ & roundBitsMask ) ) uiZ &= ~ lastBitMask;
- } else if ( roundingMode != softfloat_round_minMag ) {
- if ( signF32UI( uiZ ) ^ ( roundingMode == softfloat_round_max ) ) {
- uiZ += roundBitsMask;
- }
+ if ( ! (uiZ & roundBitsMask) ) uiZ &= ~lastBitMask;
+ } else if (
+ roundingMode
+ == (signF32UI( uiZ ) ? softfloat_round_min : softfloat_round_max)
+ ) {
+ uiZ += roundBitsMask;
}
- uiZ &= ~ roundBitsMask;
- if ( exact && ( uiZ != uiA ) ) {
+ uiZ &= ~roundBitsMask;
+ if ( exact && (uiZ != uiA) ) {
softfloat_exceptionFlags |= softfloat_flag_inexact;
}
uiZ:
projects / riscv-isa-sim.git / blobdiff