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Diffstat (limited to 'softfloat/f128_mul.c')
-rw-r--r-- | softfloat/f128_mul.c | 163 |
1 files changed, 163 insertions, 0 deletions
diff --git a/softfloat/f128_mul.c b/softfloat/f128_mul.c new file mode 100644 index 0000000..1871613 --- /dev/null +++ b/softfloat/f128_mul.c @@ -0,0 +1,163 @@ + +/*============================================================================ + +This C source file is part of the SoftFloat IEEE Floating-Point Arithmetic +Package, Release 3d, by John R. Hauser. + +Copyright 2011, 2012, 2013, 2014 The Regents of the University of California. +All rights reserved. + +Redistribution and use in source and binary forms, with or without +modification, are permitted provided that the following conditions are met: + + 1. Redistributions of source code must retain the above copyright notice, + this list of conditions, and the following disclaimer. + + 2. Redistributions in binary form must reproduce the above copyright notice, + this list of conditions, and the following disclaimer in the documentation + and/or other materials provided with the distribution. + + 3. Neither the name of the University nor the names of its contributors may + be used to endorse or promote products derived from this software without + specific prior written permission. + +THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS "AS IS", AND ANY +EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED +WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE, ARE +DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE FOR ANY +DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES +(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; +LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND +ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS +SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + +=============================================================================*/ + +#include <stdbool.h> +#include <stdint.h> +#include "platform.h" +#include "internals.h" +#include "specialize.h" +#include "softfloat.h" + +float128_t f128_mul( float128_t a, float128_t b ) +{ + union ui128_f128 uA; + uint_fast64_t uiA64, uiA0; + bool signA; + int_fast32_t expA; + struct uint128 sigA; + union ui128_f128 uB; + uint_fast64_t uiB64, uiB0; + bool signB; + int_fast32_t expB; + struct uint128 sigB; + bool signZ; + uint_fast64_t magBits; + struct exp32_sig128 normExpSig; + int_fast32_t expZ; + uint64_t sig256Z[4]; + uint_fast64_t sigZExtra; + struct uint128 sigZ; + struct uint128_extra sig128Extra; + struct uint128 uiZ; + union ui128_f128 uZ; + + /*------------------------------------------------------------------------ + *------------------------------------------------------------------------*/ + uA.f = a; + uiA64 = uA.ui.v64; + uiA0 = uA.ui.v0; + signA = signF128UI64( uiA64 ); + expA = expF128UI64( uiA64 ); + sigA.v64 = fracF128UI64( uiA64 ); + sigA.v0 = uiA0; + uB.f = b; + uiB64 = uB.ui.v64; + uiB0 = uB.ui.v0; + signB = signF128UI64( uiB64 ); + expB = expF128UI64( uiB64 ); + sigB.v64 = fracF128UI64( uiB64 ); + sigB.v0 = uiB0; + signZ = signA ^ signB; + /*------------------------------------------------------------------------ + *------------------------------------------------------------------------*/ + if ( expA == 0x7FFF ) { + if ( + (sigA.v64 | sigA.v0) || ((expB == 0x7FFF) && (sigB.v64 | sigB.v0)) + ) { + goto propagateNaN; + } + magBits = expB | sigB.v64 | sigB.v0; + goto infArg; + } + if ( expB == 0x7FFF ) { + if ( sigB.v64 | sigB.v0 ) goto propagateNaN; + magBits = expA | sigA.v64 | sigA.v0; + goto infArg; + } + /*------------------------------------------------------------------------ + *------------------------------------------------------------------------*/ + if ( ! expA ) { + if ( ! (sigA.v64 | sigA.v0) ) goto zero; + normExpSig = softfloat_normSubnormalF128Sig( sigA.v64, sigA.v0 ); + expA = normExpSig.exp; + sigA = normExpSig.sig; + } + if ( ! expB ) { + if ( ! (sigB.v64 | sigB.v0) ) goto zero; + normExpSig = softfloat_normSubnormalF128Sig( sigB.v64, sigB.v0 ); + expB = normExpSig.exp; + sigB = normExpSig.sig; + } + /*------------------------------------------------------------------------ + *------------------------------------------------------------------------*/ + expZ = expA + expB - 0x4000; + sigA.v64 |= UINT64_C( 0x0001000000000000 ); + sigB = softfloat_shortShiftLeft128( sigB.v64, sigB.v0, 16 ); + softfloat_mul128To256M( sigA.v64, sigA.v0, sigB.v64, sigB.v0, sig256Z ); + sigZExtra = sig256Z[indexWord( 4, 1 )] | (sig256Z[indexWord( 4, 0 )] != 0); + sigZ = + softfloat_add128( + sig256Z[indexWord( 4, 3 )], sig256Z[indexWord( 4, 2 )], + sigA.v64, sigA.v0 + ); + if ( UINT64_C( 0x0002000000000000 ) <= sigZ.v64 ) { + ++expZ; + sig128Extra = + softfloat_shortShiftRightJam128Extra( + sigZ.v64, sigZ.v0, sigZExtra, 1 ); + sigZ = sig128Extra.v; + sigZExtra = sig128Extra.extra; + } + return + softfloat_roundPackToF128( signZ, expZ, sigZ.v64, sigZ.v0, sigZExtra ); + /*------------------------------------------------------------------------ + *------------------------------------------------------------------------*/ + propagateNaN: + uiZ = softfloat_propagateNaNF128UI( uiA64, uiA0, uiB64, uiB0 ); + goto uiZ; + /*------------------------------------------------------------------------ + *------------------------------------------------------------------------*/ + infArg: + if ( ! magBits ) { + softfloat_raiseFlags( softfloat_flag_invalid ); + uiZ.v64 = defaultNaNF128UI64; + uiZ.v0 = defaultNaNF128UI0; + goto uiZ; + } + uiZ.v64 = packToF128UI64( signZ, 0x7FFF, 0 ); + goto uiZ0; + /*------------------------------------------------------------------------ + *------------------------------------------------------------------------*/ + zero: + uiZ.v64 = packToF128UI64( signZ, 0, 0 ); + uiZ0: + uiZ.v0 = 0; + uiZ: + uZ.ui = uiZ; + return uZ.f; + +} + |