1 2 /*============================================================================ 3 4 This C source file is part of the SoftFloat IEEE Floating-Point Arithmetic 5 Package, Release 3e, by John R. Hauser. 6 7 Copyright 2011, 2012, 2013, 2014 The Regents of the University of California. 8 All rights reserved. 9 10 Redistribution and use in source and binary forms, with or without 11 modification, are permitted provided that the following conditions are met: 12 13 1. Redistributions of source code must retain the above copyright notice, 14 this list of conditions, and the following disclaimer. 15 16 2. Redistributions in binary form must reproduce the above copyright notice, 17 this list of conditions, and the following disclaimer in the documentation 18 and/or other materials provided with the distribution. 19 20 3. Neither the name of the University nor the names of its contributors may 21 be used to endorse or promote products derived from this software without 22 specific prior written permission. 23 24 THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS "AS IS", AND ANY 25 EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED 26 WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE, ARE 27 DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE FOR ANY 28 DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES 29 (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 30 LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND 31 ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 32 (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS 33 SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 34 35 =============================================================================*/ 36 37 #include <stdbool.h> 38 #include <stdint.h> 39 #include "platform.h" 40 #include "internals.h" 41 #include "specialize.h" 42 43 float128_t softfloat_addMagsF128(uint_fast64_t uiA64,uint_fast64_t uiA0,uint_fast64_t uiB64,uint_fast64_t uiB0,bool signZ)44 softfloat_addMagsF128( 45 uint_fast64_t uiA64, 46 uint_fast64_t uiA0, 47 uint_fast64_t uiB64, 48 uint_fast64_t uiB0, 49 bool signZ 50 ) 51 { 52 int_fast32_t expA; 53 struct uint128 sigA; 54 int_fast32_t expB; 55 struct uint128 sigB; 56 int_fast32_t expDiff; 57 struct uint128 uiZ, sigZ; 58 int_fast32_t expZ; 59 uint_fast64_t sigZExtra; 60 struct uint128_extra sig128Extra; 61 union ui128_f128 uZ; 62 63 expA = expF128UI64( uiA64 ); 64 sigA.v64 = fracF128UI64( uiA64 ); 65 sigA.v0 = uiA0; 66 expB = expF128UI64( uiB64 ); 67 sigB.v64 = fracF128UI64( uiB64 ); 68 sigB.v0 = uiB0; 69 expDiff = expA - expB; 70 if ( ! expDiff ) { 71 if ( expA == 0x7FFF ) { 72 if ( sigA.v64 | sigA.v0 | sigB.v64 | sigB.v0 ) goto propagateNaN; 73 uiZ.v64 = uiA64; 74 uiZ.v0 = uiA0; 75 goto uiZ; 76 } 77 sigZ = softfloat_add128( sigA.v64, sigA.v0, sigB.v64, sigB.v0 ); 78 if ( ! expA ) { 79 uiZ.v64 = packToF128UI64( signZ, 0, sigZ.v64 ); 80 uiZ.v0 = sigZ.v0; 81 goto uiZ; 82 } 83 expZ = expA; 84 sigZ.v64 |= UINT64_C( 0x0002000000000000 ); 85 sigZExtra = 0; 86 goto shiftRight1; 87 } 88 if ( expDiff < 0 ) { 89 if ( expB == 0x7FFF ) { 90 if ( sigB.v64 | sigB.v0 ) goto propagateNaN; 91 uiZ.v64 = packToF128UI64( signZ, 0x7FFF, 0 ); 92 uiZ.v0 = 0; 93 goto uiZ; 94 } 95 expZ = expB; 96 if ( expA ) { 97 sigA.v64 |= UINT64_C( 0x0001000000000000 ); 98 } else { 99 ++expDiff; 100 sigZExtra = 0; 101 if ( ! expDiff ) goto newlyAligned; 102 } 103 sig128Extra = 104 softfloat_shiftRightJam128Extra( sigA.v64, sigA.v0, 0, -expDiff ); 105 sigA = sig128Extra.v; 106 sigZExtra = sig128Extra.extra; 107 } else { 108 if ( expA == 0x7FFF ) { 109 if ( sigA.v64 | sigA.v0 ) goto propagateNaN; 110 uiZ.v64 = uiA64; 111 uiZ.v0 = uiA0; 112 goto uiZ; 113 } 114 expZ = expA; 115 if ( expB ) { 116 sigB.v64 |= UINT64_C( 0x0001000000000000 ); 117 } else { 118 --expDiff; 119 sigZExtra = 0; 120 if ( ! expDiff ) goto newlyAligned; 121 } 122 sig128Extra = 123 softfloat_shiftRightJam128Extra( sigB.v64, sigB.v0, 0, expDiff ); 124 sigB = sig128Extra.v; 125 sigZExtra = sig128Extra.extra; 126 } 127 newlyAligned: 128 sigZ = 129 softfloat_add128( 130 sigA.v64 | UINT64_C( 0x0001000000000000 ), 131 sigA.v0, 132 sigB.v64, 133 sigB.v0 134 ); 135 --expZ; 136 if ( sigZ.v64 < UINT64_C( 0x0002000000000000 ) ) goto roundAndPack; 137 ++expZ; 138 shiftRight1: 139 sig128Extra = 140 softfloat_shortShiftRightJam128Extra( 141 sigZ.v64, sigZ.v0, sigZExtra, 1 ); 142 sigZ = sig128Extra.v; 143 sigZExtra = sig128Extra.extra; 144 roundAndPack: 145 return 146 softfloat_roundPackToF128( signZ, expZ, sigZ.v64, sigZ.v0, sigZExtra ); 147 propagateNaN: 148 uiZ = softfloat_propagateNaNF128UI( uiA64, uiA0, uiB64, uiB0 ); 149 uiZ: 150 uZ.ui = uiZ; 151 return uZ.f; 152 153 } 154 155