1 // SPDX-License-Identifier: BSD-3-Clause 2 3 /*============================================================================ 4 5 This C source file is part of the SoftFloat IEEE Floating-Point Arithmetic 6 Package, Release 3a, by John R. Hauser. 7 8 Copyright 2011, 2012, 2013, 2014 The Regents of the University of California. 9 All rights reserved. 10 11 Redistribution and use in source and binary forms, with or without 12 modification, are permitted provided that the following conditions are met: 13 14 1. Redistributions of source code must retain the above copyright notice, 15 this list of conditions, and the following disclaimer. 16 17 2. Redistributions in binary form must reproduce the above copyright notice, 18 this list of conditions, and the following disclaimer in the documentation 19 and/or other materials provided with the distribution. 20 21 3. Neither the name of the University nor the names of its contributors may 22 be used to endorse or promote products derived from this software without 23 specific prior written permission. 24 25 THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS "AS IS", AND ANY 26 EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED 27 WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE, ARE 28 DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE FOR ANY 29 DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES 30 (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 31 LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND 32 ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 33 (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS 34 SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 35 36 =============================================================================*/ 37 38 #include <stdbool.h> 39 #include <stdint.h> 40 #include "platform.h" 41 #include "internals.h" 42 #include "specialize.h" 43 #include "softfloat.h" 44 45 void softfloat_addF128M(const uint32_t * aWPtr,const uint32_t * bWPtr,uint32_t * zWPtr,bool negateB)46 softfloat_addF128M( 47 const uint32_t *aWPtr, 48 const uint32_t *bWPtr, 49 uint32_t *zWPtr, 50 bool negateB 51 ) 52 { 53 uint32_t uiA96; 54 int32_t expA; 55 uint32_t uiB96; 56 int32_t expB; 57 uint32_t uiZ96; 58 bool signZ, signB; 59 const uint32_t *tempPtr; 60 uint32_t sig96A, sig96B; 61 int32_t expDiff; 62 uint_fast8_t 63 (*addCarryMRoutinePtr)( 64 uint_fast8_t, 65 const uint32_t *, 66 const uint32_t *, 67 uint_fast8_t, 68 uint32_t * 69 ); 70 uint32_t extSigZ[5], wordSigZ; 71 uint_fast8_t carry; 72 void (*roundPackRoutinePtr)( bool, int32_t, uint32_t *, uint32_t * ); 73 74 /*------------------------------------------------------------------------ 75 *------------------------------------------------------------------------*/ 76 uiA96 = aWPtr[indexWordHi( 4 )]; 77 expA = expF128UI96( uiA96 ); 78 uiB96 = bWPtr[indexWordHi( 4 )]; 79 expB = expF128UI96( uiB96 ); 80 /*------------------------------------------------------------------------ 81 *------------------------------------------------------------------------*/ 82 if ( (expA == 0x7FFF) || (expB == 0x7FFF) ) { 83 if ( softfloat_tryPropagateNaNF128M( aWPtr, bWPtr, zWPtr ) ) return; 84 uiZ96 = uiA96; 85 if ( expB == 0x7FFF ) { 86 uiZ96 = uiB96 ^ packToF128UI96( negateB, 0, 0 ); 87 if ( (expA == 0x7FFF) && (uiZ96 != uiA96) ) { 88 softfloat_invalidF128M( zWPtr ); 89 return; 90 } 91 } 92 zWPtr[indexWordHi( 4 )] = uiZ96; 93 zWPtr[indexWord( 4, 2 )] = 0; 94 zWPtr[indexWord( 4, 1 )] = 0; 95 zWPtr[indexWord( 4, 0 )] = 0; 96 return; 97 } 98 /*------------------------------------------------------------------------ 99 *------------------------------------------------------------------------*/ 100 signZ = signF128UI96( uiA96 ); 101 signB = signF128UI96( uiB96 ) ^ negateB; 102 negateB = (signZ != signB); 103 if ( (uint32_t) (uiA96<<1) < (uint32_t) (uiB96<<1) ) { 104 signZ = signB; 105 expA = expB; 106 expB = expF128UI96( uiA96 ); 107 tempPtr = aWPtr; 108 aWPtr = bWPtr; 109 bWPtr = tempPtr; 110 uiA96 = uiB96; 111 uiB96 = bWPtr[indexWordHi( 4 )]; 112 } 113 sig96A = fracF128UI96( uiA96 ); 114 sig96B = fracF128UI96( uiB96 ); 115 if ( expA ) { 116 --expA; 117 sig96A |= 0x00010000; 118 if ( expB ) { 119 --expB; 120 sig96B |= 0x00010000; 121 } 122 } 123 /*------------------------------------------------------------------------ 124 *------------------------------------------------------------------------*/ 125 addCarryMRoutinePtr = 126 negateB ? softfloat_addComplCarryM : softfloat_addCarryM; 127 expDiff = expA - expB; 128 if ( expDiff ) { 129 /*-------------------------------------------------------------------- 130 *--------------------------------------------------------------------*/ 131 extSigZ[indexWordHi( 5 )] = sig96B; 132 extSigZ[indexWord( 5, 3 )] = bWPtr[indexWord( 4, 2 )]; 133 extSigZ[indexWord( 5, 2 )] = bWPtr[indexWord( 4, 1 )]; 134 extSigZ[indexWord( 5, 1 )] = bWPtr[indexWord( 4, 0 )]; 135 extSigZ[indexWord( 5, 0 )] = 0; 136 softfloat_shiftRightJam160M( extSigZ, expDiff, extSigZ ); 137 sig96B = extSigZ[indexWordHi( 5 )]; 138 carry = 0; 139 if ( negateB ) { 140 sig96B = ~sig96B; 141 wordSigZ = extSigZ[indexWordLo( 5 )]; 142 extSigZ[indexWordLo( 5 )] = -wordSigZ; 143 carry = ! wordSigZ; 144 } 145 carry = 146 (*addCarryMRoutinePtr)( 147 3, 148 &aWPtr[indexMultiwordLo( 4, 3 )], 149 &extSigZ[indexMultiword( 5, 3, 1 )], 150 carry, 151 &extSigZ[indexMultiword( 5, 3, 1 )] 152 ); 153 wordSigZ = sig96A + sig96B + carry; 154 } else { 155 /*-------------------------------------------------------------------- 156 *--------------------------------------------------------------------*/ 157 extSigZ[indexWordLo( 5 )] = 0; 158 carry = 159 (*addCarryMRoutinePtr)( 160 3, 161 &aWPtr[indexMultiwordLo( 4, 3 )], 162 &bWPtr[indexMultiwordLo( 4, 3 )], 163 negateB, 164 &extSigZ[indexMultiword( 5, 3, 1 )] 165 ); 166 if ( negateB ) { 167 wordSigZ = sig96A + ~sig96B + carry; 168 if ( wordSigZ & 0x80000000 ) { 169 signZ = ! signZ; 170 carry = 171 softfloat_addComplCarry96M( 172 &bWPtr[indexMultiwordLo( 4, 3 )], 173 &aWPtr[indexMultiwordLo( 4, 3 )], 174 1, 175 &extSigZ[indexMultiword( 5, 3, 1 )] 176 ); 177 wordSigZ = sig96B + ~sig96A + carry; 178 } else { 179 if ( 180 ! wordSigZ && ! extSigZ[indexWord( 5, 3 )] 181 && ! ( extSigZ[indexWord( 5, 2 )] 182 | extSigZ[indexWord( 5, 1 )] 183 | extSigZ[indexWord( 5, 0 )] 184 ) 185 ) { 186 signZ = (softfloat_roundingMode == softfloat_round_min); 187 zWPtr[indexWordHi( 4 )] = packToF128UI96( signZ, 0, 0 ); 188 zWPtr[indexWord( 4, 2 )] = 0; 189 zWPtr[indexWord( 4, 1 )] = 0; 190 zWPtr[indexWord( 4, 0 )] = 0; 191 return; 192 } 193 } 194 } else { 195 wordSigZ = sig96A + sig96B + carry; 196 } 197 } 198 extSigZ[indexWordHi( 5 )] = wordSigZ; 199 /*------------------------------------------------------------------------ 200 *------------------------------------------------------------------------*/ 201 roundPackRoutinePtr = softfloat_normRoundPackMToF128M; 202 if ( 0x00010000 <= wordSigZ ) { 203 if ( 0x00020000 <= wordSigZ ) { 204 ++expA; 205 softfloat_shortShiftRightJam160M( extSigZ, 1, extSigZ ); 206 } 207 roundPackRoutinePtr = softfloat_roundPackMToF128M; 208 } 209 (*roundPackRoutinePtr)( signZ, expA, extSigZ, zWPtr ); 210 211 } 212 213