91 lines
3.4 KiB
C
91 lines
3.4 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 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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float32_t bf16_to_f32( bfloat16_t a )
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{
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union ui16_bf16 uA;
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uint_fast16_t uiA;
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bool sign;
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int_fast16_t exp;
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uint_fast16_t frac;
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struct commonNaN commonNaN;
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uint_fast32_t uiZ;
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struct exp8_sig16 normExpSig;
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union ui32_f32 uZ;
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/*------------------------------------------------------------------------
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*------------------------------------------------------------------------*/
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uA.f = a;
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uiA = uA.ui;
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sign = signBF16UI( uiA );
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exp = expBF16UI( uiA );
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frac = fracBF16UI( uiA );
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/*------------------------------------------------------------------------
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*------------------------------------------------------------------------*/
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// NaN or Inf
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if ( exp == 0xFF ) {
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if ( frac ) {
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softfloat_bf16UIToCommonNaN( uiA, &commonNaN );
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uiZ = softfloat_commonNaNToF32UI( &commonNaN );
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} else {
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uiZ = packToF32UI( sign, 0xFF, 0 );
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}
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goto uiZ;
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}
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/*------------------------------------------------------------------------
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*------------------------------------------------------------------------*/
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// packToF32UI simply packs bitfields without any numerical change
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// which means it can be used directly for any BF16 to f32 conversions which
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// does not require bits manipulation
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// (that is everything where the 16-bit are just padded right with 16 zeros, including
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// subnormal numbers)
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uiZ = packToF32UI( sign, exp, ((uint_fast32_t) frac) <<16 );
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uiZ:
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uZ.ui = uiZ;
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return uZ.f;
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}
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