Eyck Jentzsch
dcaf5467e8
(http://www.jhauser.us/arithmetic/SoftFloat.html) with RISCV specialization and cmake build
85 lines
3.8 KiB
C
85 lines
3.8 KiB
C
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/*============================================================================
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This C source file is part of the SoftFloat IEEE Floating-Point Arithmetic
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Package, Release 3e, by John R. Hauser.
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Copyright 2011, 2012, 2013, 2014, 2018 The Regents of the University of
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California. All rights reserved.
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Redistribution and use in source and binary forms, with or without
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modification, are permitted provided that the following conditions are met:
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1. Redistributions of source code must retain the above copyright notice,
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this list of conditions, and the following disclaimer.
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2. Redistributions in binary form must reproduce the above copyright notice,
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this list of conditions, and the following disclaimer in the documentation
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and/or other materials provided with the distribution.
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3. Neither the name of the University nor the names of its contributors may
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be used to endorse or promote products derived from this software without
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specific prior written permission.
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THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS "AS IS", AND ANY
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EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
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WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE, ARE
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DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE FOR ANY
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DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
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(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
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LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
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ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
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SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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=============================================================================*/
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#include <stdbool.h>
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#include <stdint.h>
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#include "platform.h"
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#include "internals.h"
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#include "specialize.h"
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#include "softfloat.h"
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/*----------------------------------------------------------------------------
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| Interpreting 'uiA' and 'uiB' as the bit patterns of two 32-bit floating-
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| point values, at least one of which is a NaN, returns the bit pattern of
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| the combined NaN result. If either 'uiA' or 'uiB' has the pattern of a
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| signaling NaN, the invalid exception is raised.
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*----------------------------------------------------------------------------*/
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uint_fast32_t
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softfloat_propagateNaNF32UI( uint_fast32_t uiA, uint_fast32_t uiB )
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{
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bool isSigNaNA, isSigNaNB;
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uint_fast32_t uiNonsigA, uiNonsigB, uiMagA, uiMagB;
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/*------------------------------------------------------------------------
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*------------------------------------------------------------------------*/
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isSigNaNA = softfloat_isSigNaNF32UI( uiA );
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isSigNaNB = softfloat_isSigNaNF32UI( uiB );
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/*------------------------------------------------------------------------
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| Make NaNs non-signaling.
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*------------------------------------------------------------------------*/
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uiNonsigA = uiA | 0x00400000;
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uiNonsigB = uiB | 0x00400000;
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/*------------------------------------------------------------------------
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*------------------------------------------------------------------------*/
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if ( isSigNaNA | isSigNaNB ) {
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softfloat_raiseFlags( softfloat_flag_invalid );
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if ( isSigNaNA ) {
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if ( isSigNaNB ) goto returnLargerMag;
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return isNaNF32UI( uiB ) ? uiNonsigB : uiNonsigA;
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} else {
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return isNaNF32UI( uiA ) ? uiNonsigA : uiNonsigB;
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}
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}
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returnLargerMag:
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uiMagA = uiA & 0x7FFFFFFF;
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uiMagB = uiB & 0x7FFFFFFF;
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if ( uiMagA < uiMagB ) return uiNonsigB;
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if ( uiMagB < uiMagA ) return uiNonsigA;
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return (uiNonsigA < uiNonsigB) ? uiNonsigA : uiNonsigB;
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}
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