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Diffstat (limited to 'source/s_addMagsF64.c')
-rw-r--r-- | source/s_addMagsF64.c | 108 |
1 files changed, 108 insertions, 0 deletions
diff --git a/source/s_addMagsF64.c b/source/s_addMagsF64.c new file mode 100644 index 0000000..93a7b11 --- /dev/null +++ b/source/s_addMagsF64.c @@ -0,0 +1,108 @@ + +/*============================================================================ + +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" + +float64_t + softfloat_addMagsF64( uint_fast64_t uiA, uint_fast64_t uiB, bool signZ ) +{ + int_fast16_t expA; + uint_fast64_t sigA; + int_fast16_t expB; + uint_fast64_t sigB; + int_fast16_t expDiff; + uint_fast64_t uiZ; + int_fast16_t expZ; + uint_fast64_t sigZ; + union ui64_f64 uZ; + + expA = expF64UI( uiA ); + sigA = fracF64UI( uiA ); + expB = expF64UI( uiB ); + sigB = fracF64UI( uiB ); + expDiff = expA - expB; + sigA <<= 9; + sigB <<= 9; + if ( ! expDiff ) { + if ( expA == 0x7FF ) { + if ( sigA | sigB ) goto propagateNaN; + uiZ = uiA; + goto uiZ; + } + if ( ! expA ) { + uiZ = + packToF64UI( + signZ, 0, (uiA + uiB) & UINT64_C( 0x7FFFFFFFFFFFFFFF ) ); + goto uiZ; + } + expZ = expA; + sigZ = UINT64_C( 0x4000000000000000 ) + sigA + sigB; + } else { + if ( expDiff < 0 ) { + if ( expB == 0x7FF ) { + if ( sigB ) goto propagateNaN; + uiZ = packToF64UI( signZ, 0x7FF, 0 ); + goto uiZ; + } + expZ = expB; + sigA += expA ? UINT64_C( 0x2000000000000000 ) : sigA; + sigA = softfloat_shiftRightJam64( sigA, -expDiff ); + } else { + if ( expA == 0x7FF ) { + if ( sigA ) goto propagateNaN; + uiZ = uiA; + goto uiZ; + } + expZ = expA; + sigB += expB ? UINT64_C( 0x2000000000000000 ) : sigB; + sigB = softfloat_shiftRightJam64( sigB, expDiff ); + } + sigZ = UINT64_C( 0x2000000000000000 ) + sigA + sigB; + if ( sigZ < UINT64_C( 0x4000000000000000 ) ) { + --expZ; + sigZ <<= 1; + } + } + return softfloat_roundPackToF64( signZ, expZ, sigZ ); + propagateNaN: + uiZ = softfloat_propagateNaNF64UI( uiA, uiB ); + uiZ: + uZ.ui = uiZ; + return uZ.f; + +} + |