Eyck Jentzsch
dcaf5467e8
(http://www.jhauser.us/arithmetic/SoftFloat.html) with RISCV specialization and cmake build
109 lines
4.1 KiB
C
109 lines
4.1 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, 2015, 2016 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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#ifdef SOFTFLOAT_FAST_INT64
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uint_fast64_t extF80M_to_ui64_r_minMag( const extFloat80_t *aPtr, bool exact )
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{
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return extF80_to_ui64_r_minMag( *aPtr, exact );
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}
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#else
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uint_fast64_t extF80M_to_ui64_r_minMag( const extFloat80_t *aPtr, bool exact )
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{
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const struct extFloat80M *aSPtr;
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uint_fast16_t uiA64;
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int32_t exp;
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uint64_t sig;
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int32_t shiftDist;
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bool sign;
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uint64_t z;
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/*------------------------------------------------------------------------
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*------------------------------------------------------------------------*/
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aSPtr = (const struct extFloat80M *) aPtr;
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uiA64 = aSPtr->signExp;
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exp = expExtF80UI64( uiA64 );
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sig = aSPtr->signif;
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/*------------------------------------------------------------------------
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*------------------------------------------------------------------------*/
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if ( ! sig && (exp != 0x7FFF) ) return 0;
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shiftDist = 0x403E - exp;
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if ( 64 <= shiftDist ) {
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if ( exact ) softfloat_exceptionFlags |= softfloat_flag_inexact;
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return 0;
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}
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/*------------------------------------------------------------------------
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*------------------------------------------------------------------------*/
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sign = signExtF80UI64( uiA64 );
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if ( shiftDist < 0 ) {
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if ( sign || (shiftDist <= -63) ) goto invalid;
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shiftDist = -shiftDist;
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z = sig<<shiftDist;
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if ( z>>shiftDist != sig ) goto invalid;
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} else {
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z = sig;
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if ( shiftDist ) z >>= shiftDist;
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if ( sign && z ) goto invalid;
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if ( exact && shiftDist && (z<<shiftDist != sig) ) {
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softfloat_exceptionFlags |= softfloat_flag_inexact;
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}
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}
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return z;
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/*------------------------------------------------------------------------
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*------------------------------------------------------------------------*/
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invalid:
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softfloat_raiseFlags( softfloat_flag_invalid );
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return
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(exp == 0x7FFF) && (sig & UINT64_C( 0x7FFFFFFFFFFFFFFF ))
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? ui64_fromNaN
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: sign ? ui64_fromNegOverflow : ui64_fromPosOverflow;
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}
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#endif
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