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121 lines
4.4 KiB
C
121 lines
4.4 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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int_fast32_t extF80M_to_i32_r_minMag( const extFloat80_t *aPtr, bool exact )
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{
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return extF80_to_i32_r_minMag( *aPtr, exact );
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}
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#else
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int_fast32_t extF80M_to_i32_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, raiseInexact;
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int32_t z;
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uint64_t shiftedSig;
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uint32_t absZ;
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union { uint32_t ui; int32_t i; } u;
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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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raiseInexact = exact;
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z = 0;
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} else {
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sign = signExtF80UI64( uiA64 );
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raiseInexact = false;
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if ( shiftDist < 0 ) {
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if ( sig>>32 || (shiftDist <= -31) ) goto invalid;
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shiftedSig = (uint64_t) (uint32_t) sig<<-shiftDist;
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if ( shiftedSig>>32 ) goto invalid;
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absZ = shiftedSig;
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} else {
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shiftedSig = sig;
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if ( shiftDist ) shiftedSig >>= shiftDist;
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if ( shiftedSig>>32 ) goto invalid;
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absZ = shiftedSig;
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if ( exact && shiftDist ) {
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raiseInexact = ((uint64_t) absZ<<shiftDist != sig);
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}
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}
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if ( sign ) {
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if ( 0x80000000 < absZ ) goto invalid;
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u.ui = -absZ;
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z = u.i;
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} else {
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if ( 0x80000000 <= absZ ) goto invalid;
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z = absZ;
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}
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}
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if ( raiseInexact ) softfloat_exceptionFlags |= softfloat_flag_inexact;
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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 )) ? i32_fromNaN
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: sign ? i32_fromNegOverflow : i32_fromPosOverflow;
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}
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#endif
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