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Diffstat (limited to 'source/s_addExtF80M.c')
| -rw-r--r-- | source/s_addExtF80M.c | 183 |
1 files changed, 183 insertions, 0 deletions
diff --git a/source/s_addExtF80M.c b/source/s_addExtF80M.c new file mode 100644 index 0000000..f396a7a --- /dev/null +++ b/source/s_addExtF80M.c @@ -0,0 +1,183 @@ + +/*============================================================================ + +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" + +void + softfloat_addExtF80M( + const struct extFloat80M *aSPtr, + const struct extFloat80M *bSPtr, + struct extFloat80M *zSPtr, + bool negateB + ) +{ + uint32_t uiA64; + int32_t expA; + uint32_t uiB64; + int32_t expB; + uint32_t uiZ64; + bool signZ, signB; + const struct extFloat80M *tempSPtr; + uint64_t sigZ, sigB; + void + (*roundPackRoutinePtr)( + bool, int32_t, uint32_t *, uint_fast8_t, struct extFloat80M * ); + int32_t expDiff; + uint32_t extSigX[3], sigZExtra; + + /*------------------------------------------------------------------------ + *------------------------------------------------------------------------*/ + uiA64 = aSPtr->signExp; + expA = expExtF80UI64( uiA64 ); + uiB64 = bSPtr->signExp; + expB = expExtF80UI64( uiB64 ); + /*------------------------------------------------------------------------ + *------------------------------------------------------------------------*/ + if ( (expA == 0x7FFF) || (expB == 0x7FFF) ) { + if ( softfloat_tryPropagateNaNExtF80M( aSPtr, bSPtr, zSPtr ) ) return; + uiZ64 = uiA64; + if ( expB == 0x7FFF ) { + uiZ64 = uiB64 ^ packToExtF80UI64( negateB, 0 ); + if ( (expA == 0x7FFF) && (uiZ64 != uiA64) ) { + softfloat_invalidExtF80M( zSPtr ); + return; + } + } + zSPtr->signExp = uiZ64; + zSPtr->signif = UINT64_C( 0x8000000000000000 ); + return; + } + /*------------------------------------------------------------------------ + *------------------------------------------------------------------------*/ + signZ = signExtF80UI64( uiA64 ); + signB = signExtF80UI64( uiB64 ) ^ negateB; + negateB = (signZ != signB); + if ( expA < expB ) { + signZ = signB; + expA = expB; + expB = expExtF80UI64( uiA64 ); + tempSPtr = aSPtr; + aSPtr = bSPtr; + bSPtr = tempSPtr; + } + if ( ! expB ) { + expB = 1; + if ( ! expA ) expA = 1; + } + sigZ = aSPtr->signif; + sigB = bSPtr->signif; + /*------------------------------------------------------------------------ + *------------------------------------------------------------------------*/ + roundPackRoutinePtr = softfloat_roundPackMToExtF80M; + expDiff = expA - expB; + if ( expDiff ) { + /*-------------------------------------------------------------------- + *--------------------------------------------------------------------*/ + extSigX[indexWord( 3, 2 )] = sigB>>32; + extSigX[indexWord( 3, 1 )] = sigB; + extSigX[indexWord( 3, 0 )] = 0; + softfloat_shiftRightJam96M( extSigX, expDiff, extSigX ); + sigB = + (uint64_t) extSigX[indexWord( 3, 2 )]<<32 + | extSigX[indexWord( 3, 1 )]; + if ( negateB ) { + sigZ -= sigB; + sigZExtra = extSigX[indexWordLo( 3 )]; + if ( sigZExtra ) { + --sigZ; + sigZExtra = -sigZExtra; + } + if ( ! (sigZ & UINT64_C( 0x8000000000000000 )) ) { + if ( sigZ & UINT64_C( 0x4000000000000000 ) ) { + --expA; + sigZ = sigZ<<1 | sigZExtra>>31; + sigZExtra <<= 1; + } else { + roundPackRoutinePtr = softfloat_normRoundPackMToExtF80M; + } + } + } else { + sigZ += sigB; + if ( sigZ & UINT64_C( 0x8000000000000000 ) ) goto sigZ; + sigZExtra = (uint32_t) sigZ<<31 | (extSigX[indexWordLo( 3 )] != 0); + goto completeNormAfterAdd; + } + } else { + /*-------------------------------------------------------------------- + *--------------------------------------------------------------------*/ + sigZExtra = 0; + if ( negateB ) { + if ( sigZ < sigB ) { + signZ = ! signZ; + sigZ = sigB - sigZ; + } else { + sigZ -= sigB; + if ( ! sigZ ) { + signZ = (softfloat_roundingMode == softfloat_round_min); + zSPtr->signExp = packToExtF80UI64( signZ, 0 ); + zSPtr->signif = 0; + return; + } + } + roundPackRoutinePtr = softfloat_normRoundPackMToExtF80M; + } else { + sigZ += sigB; + if ( sigZ < sigB ) { + sigZExtra = (uint32_t) sigZ<<31; + completeNormAfterAdd: + ++expA; + sigZ = UINT64_C( 0x8000000000000000 ) | sigZ>>1; + } else { + if ( ! (sigZ & UINT64_C( 0x8000000000000000 )) ) { + roundPackRoutinePtr = softfloat_normRoundPackMToExtF80M; + } + } + } + } + extSigX[indexWord( 3, 0 )] = sigZExtra; + sigZ: + extSigX[indexWord( 3, 2 )] = sigZ>>32; + extSigX[indexWord( 3, 1 )] = sigZ; + /*------------------------------------------------------------------------ + *------------------------------------------------------------------------*/ + roundPack: + (*roundPackRoutinePtr)( + signZ, expA, extSigX, extF80_roundingPrecision, zSPtr ); + +} + |