| |
| /*============================================================================ |
| |
| This C source file is part of the SoftFloat IEEE Floating-Point Arithmetic |
| Package, Release 3, by John R. Hauser. |
| |
| Copyright 2011, 2012, 2013, 2014 The Regents of the University of California |
| (Regents). All Rights Reserved. Redistribution and use in source and binary |
| forms, with or without modification, are permitted provided that the following |
| conditions are met: |
| |
| Redistributions of source code must retain the above copyright notice, |
| this list of conditions, and the following two paragraphs of disclaimer. |
| Redistributions in binary form must reproduce the above copyright notice, |
| this list of conditions, and the following two paragraphs of disclaimer in the |
| documentation and/or other materials provided with the distribution. Neither |
| the name of the Regents nor the names of its contributors may be used to |
| endorse or promote products derived from this software without specific prior |
| written permission. |
| |
| IN NO EVENT SHALL REGENTS BE LIABLE TO ANY PARTY FOR DIRECT, INDIRECT, |
| SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES, INCLUDING LOST PROFITS, ARISING |
| OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF REGENTS HAS |
| BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| |
| REGENTS SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING, BUT NOT LIMITED |
| TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR |
| PURPOSE. THE SOFTWARE AND ACCOMPANYING DOCUMENTATION, IF ANY, PROVIDED |
| HEREUNDER IS PROVIDED "AS IS". REGENTS HAS NO OBLIGATION TO PROVIDE |
| MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS. |
| |
| =============================================================================*/ |
| |
| #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; |
| |
| } |
| |