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69 lines
2.6 KiB
C
69 lines
2.6 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 3c, 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 <stdint.h>
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#include "platform.h"
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#include "internals.h"
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#include "softfloat.h"
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float128_t ui64_to_f128( uint64_t a )
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{
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uint_fast64_t uiZ64, uiZ0;
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int_fast8_t shiftDist;
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struct uint128 zSig;
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union ui128_f128 uZ;
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if ( ! a ) {
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uiZ64 = 0;
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uiZ0 = 0;
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} else {
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shiftDist = softfloat_countLeadingZeros64( a ) + 49;
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if ( 64 <= shiftDist ) {
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zSig.v64 = a<<(shiftDist - 64);
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zSig.v0 = 0;
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} else {
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zSig = softfloat_shortShiftLeft128( 0, a, shiftDist );
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}
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uiZ64 = packToF128UI64( 0, 0x406E - shiftDist, zSig.v64 );
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uiZ0 = zSig.v0;
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}
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uZ.ui.v64 = uiZ64;
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uZ.ui.v0 = uiZ0;
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return uZ.f;
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}
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