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156 lines
5.9 KiB
C
156 lines
5.9 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 3, by John R. Hauser.
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Copyright 2011, 2012, 2013, 2014 The Regents of the University of California
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(Regents). All Rights Reserved. Redistribution and use in source and binary
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forms, with or without modification, are permitted provided that the following
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conditions are met:
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Redistributions of source code must retain the above copyright notice,
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this list of conditions, and the following two paragraphs of disclaimer.
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Redistributions in binary form must reproduce the above copyright notice,
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this list of conditions, and the following two paragraphs of disclaimer in the
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documentation and/or other materials provided with the distribution. Neither
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the name of the Regents nor the names of its contributors may be used to
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endorse or promote products derived from this software without specific prior
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written permission.
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IN NO EVENT SHALL REGENTS BE LIABLE TO ANY PARTY FOR DIRECT, INDIRECT,
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SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES, INCLUDING LOST PROFITS, ARISING
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OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF REGENTS HAS
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BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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REGENTS SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING, BUT NOT LIMITED
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TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
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PURPOSE. THE SOFTWARE AND ACCOMPANYING DOCUMENTATION, IF ANY, PROVIDED
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HEREUNDER IS PROVIDED "AS IS". REGENTS HAS NO OBLIGATION TO PROVIDE
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MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
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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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extFloat80_t extF80_mul( extFloat80_t a, extFloat80_t b )
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{
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union { struct extFloat80M s; extFloat80_t f; } uA;
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uint_fast16_t uiA64;
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uint_fast64_t uiA0;
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bool signA;
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int_fast32_t expA;
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uint_fast64_t sigA;
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union { struct extFloat80M s; extFloat80_t f; } uB;
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uint_fast16_t uiB64;
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uint_fast64_t uiB0;
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bool signB;
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int_fast32_t expB;
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uint_fast64_t sigB;
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bool signZ;
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uint_fast64_t magBits;
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struct exp32_sig64 normExpSig;
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int_fast32_t expZ;
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struct uint128 sig128Z, uiZ;
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uint_fast16_t uiZ64;
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uint_fast64_t uiZ0;
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union { struct extFloat80M s; extFloat80_t f; } uZ;
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/*------------------------------------------------------------------------
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*------------------------------------------------------------------------*/
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uA.f = a;
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uiA64 = uA.s.signExp;
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uiA0 = uA.s.signif;
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signA = signExtF80UI64( uiA64 );
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expA = expExtF80UI64( uiA64 );
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sigA = uiA0;
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uB.f = b;
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uiB64 = uB.s.signExp;
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uiB0 = uB.s.signif;
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signB = signExtF80UI64( uiB64 );
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expB = expExtF80UI64( uiB64 );
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sigB = uiB0;
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signZ = signA ^ signB;
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/*------------------------------------------------------------------------
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*------------------------------------------------------------------------*/
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if ( expA == 0x7FFF ) {
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if (
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(sigA & UINT64_C( 0x7FFFFFFFFFFFFFFF ))
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|| ((expB == 0x7FFF) && (sigB & UINT64_C( 0x7FFFFFFFFFFFFFFF )))
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) {
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goto propagateNaN;
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}
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magBits = expB | sigB;
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goto infArg;
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}
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if ( expB == 0x7FFF ) {
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if ( sigB & UINT64_C( 0x7FFFFFFFFFFFFFFF ) ) goto propagateNaN;
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magBits = expA | sigA;
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goto infArg;
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}
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/*------------------------------------------------------------------------
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*------------------------------------------------------------------------*/
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if ( ! expA ) expA = 1;
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if ( ! (sigA & UINT64_C( 0x8000000000000000 )) ) {
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if ( ! sigA ) goto zero;
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normExpSig = softfloat_normSubnormalExtF80Sig( sigA );
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expA += normExpSig.exp;
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sigA = normExpSig.sig;
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}
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if ( ! expB ) expB = 1;
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if ( ! (sigB & UINT64_C( 0x8000000000000000 )) ) {
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if ( ! sigB ) goto zero;
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normExpSig = softfloat_normSubnormalExtF80Sig( sigB );
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expB += normExpSig.exp;
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sigB = normExpSig.sig;
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}
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/*------------------------------------------------------------------------
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*------------------------------------------------------------------------*/
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expZ = expA + expB - 0x3FFE;
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sig128Z = softfloat_mul64To128( sigA, sigB );
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if ( sig128Z.v64 < UINT64_C( 0x8000000000000000 ) ) {
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--expZ;
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sig128Z =
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softfloat_add128(
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sig128Z.v64, sig128Z.v0, sig128Z.v64, sig128Z.v0 );
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}
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return
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softfloat_roundPackToExtF80(
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signZ, expZ, sig128Z.v64, sig128Z.v0, extF80_roundingPrecision );
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/*------------------------------------------------------------------------
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*------------------------------------------------------------------------*/
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propagateNaN:
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uiZ = softfloat_propagateNaNExtF80UI( uiA64, uiA0, uiB64, uiB0 );
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uiZ64 = uiZ.v64;
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uiZ0 = uiZ.v0;
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goto uiZ;
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/*------------------------------------------------------------------------
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*------------------------------------------------------------------------*/
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infArg:
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if ( ! magBits ) {
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softfloat_raiseFlags( softfloat_flag_invalid );
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uiZ64 = defaultNaNExtF80UI64;
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uiZ0 = defaultNaNExtF80UI0;
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} else {
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uiZ64 = packToExtF80UI64( signZ, 0x7FFF );
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uiZ0 = UINT64_C( 0x8000000000000000 );
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}
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goto uiZ;
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/*------------------------------------------------------------------------
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*------------------------------------------------------------------------*/
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zero:
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uiZ64 = packToExtF80UI64( signZ, 0 );
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uiZ0 = 0;
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uiZ:
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uZ.s.signExp = uiZ64;
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uZ.s.signif = uiZ0;
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return uZ.f;
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}
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