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 #include "softfloat.h" 43 44 #ifdef SOFTFLOAT_FAST_INT64 45 46 void f128M_rem(const float128_t * aPtr,const float128_t * bPtr,float128_t * zPtr)47 f128M_rem( const float128_t *aPtr, const float128_t *bPtr, float128_t *zPtr ) 48 { 49 50 *zPtr = f128_rem( *aPtr, *bPtr ); 51 52 } 53 54 #else 55 56 void f128M_rem(const float128_t * aPtr,const float128_t * bPtr,float128_t * zPtr)57 f128M_rem( const float128_t *aPtr, const float128_t *bPtr, float128_t *zPtr ) 58 { 59 const uint32_t *aWPtr, *bWPtr; 60 uint32_t *zWPtr, uiA96; 61 int32_t expA, expB; 62 uint32_t x[4], rem1[5], *remPtr; 63 bool signRem; 64 int32_t expDiff; 65 uint32_t q, recip32; 66 uint64_t q64; 67 uint32_t rem2[5], *altRemPtr, *newRemPtr, wordMeanRem; 68 69 /*------------------------------------------------------------------------ 70 *------------------------------------------------------------------------*/ 71 aWPtr = (const uint32_t *) aPtr; 72 bWPtr = (const uint32_t *) bPtr; 73 zWPtr = (uint32_t *) zPtr; 74 /*------------------------------------------------------------------------ 75 *------------------------------------------------------------------------*/ 76 uiA96 = aWPtr[indexWordHi( 4 )]; 77 expA = expF128UI96( uiA96 ); 78 expB = expF128UI96( bWPtr[indexWordHi( 4 )] ); 79 /*------------------------------------------------------------------------ 80 *------------------------------------------------------------------------*/ 81 if ( (expA == 0x7FFF) || (expB == 0x7FFF) ) { 82 if ( softfloat_tryPropagateNaNF128M( aWPtr, bWPtr, zWPtr ) ) return; 83 if ( expA == 0x7FFF ) goto invalid; 84 goto copyA; 85 } 86 /*------------------------------------------------------------------------ 87 *------------------------------------------------------------------------*/ 88 if ( expA < expB - 1 ) goto copyA; 89 /*------------------------------------------------------------------------ 90 *------------------------------------------------------------------------*/ 91 expB = softfloat_shiftNormSigF128M( bWPtr, 13, x ); 92 if ( expB == -128 ) goto invalid; 93 remPtr = &rem1[indexMultiwordLo( 5, 4 )]; 94 expA = softfloat_shiftNormSigF128M( aWPtr, 13, remPtr ); 95 if ( expA == -128 ) goto copyA; 96 signRem = signF128UI96( uiA96 ); 97 /*------------------------------------------------------------------------ 98 *------------------------------------------------------------------------*/ 99 expDiff = expA - expB; 100 if ( expDiff < 1 ) { 101 if ( expDiff < -1 ) goto copyA; 102 if ( expDiff ) { 103 --expB; 104 softfloat_add128M( x, x, x ); 105 q = 0; 106 } else { 107 q = (softfloat_compare128M( x, remPtr ) <= 0); 108 if ( q ) softfloat_sub128M( remPtr, x, remPtr ); 109 } 110 } else { 111 recip32 = 112 softfloat_approxRecip32_1( 113 ((uint64_t) x[indexWord( 4, 3 )]<<32 | x[indexWord( 4, 2 )]) 114 >>30 115 ); 116 expDiff -= 30; 117 for (;;) { 118 q64 = (uint64_t) remPtr[indexWordHi( 4 )] * recip32; 119 if ( expDiff < 0 ) break; 120 q = (q64 + 0x80000000)>>32; 121 softfloat_remStep128MBy32( remPtr, 29, x, q, remPtr ); 122 if ( remPtr[indexWordHi( 4 )] & 0x80000000 ) { 123 softfloat_add128M( remPtr, x, remPtr ); 124 } 125 expDiff -= 29; 126 } 127 /*-------------------------------------------------------------------- 128 | (`expDiff' cannot be less than -29 here.) 129 *--------------------------------------------------------------------*/ 130 q = (uint32_t) (q64>>32)>>(~expDiff & 31); 131 softfloat_remStep128MBy32( remPtr, expDiff + 30, x, q, remPtr ); 132 if ( remPtr[indexWordHi( 4 )] & 0x80000000 ) { 133 altRemPtr = &rem2[indexMultiwordLo( 5, 4 )]; 134 softfloat_add128M( remPtr, x, altRemPtr ); 135 goto selectRem; 136 } 137 } 138 /*------------------------------------------------------------------------ 139 *------------------------------------------------------------------------*/ 140 altRemPtr = &rem2[indexMultiwordLo( 5, 4 )]; 141 do { 142 ++q; 143 newRemPtr = altRemPtr; 144 softfloat_sub128M( remPtr, x, newRemPtr ); 145 altRemPtr = remPtr; 146 remPtr = newRemPtr; 147 } while ( ! (remPtr[indexWordHi( 4 )] & 0x80000000) ); 148 selectRem: 149 softfloat_add128M( remPtr, altRemPtr, x ); 150 wordMeanRem = x[indexWordHi( 4 )]; 151 if ( 152 (wordMeanRem & 0x80000000) 153 || (! wordMeanRem && (q & 1) && ! x[indexWord( 4, 0 )] 154 && ! (x[indexWord( 4, 2 )] | x[indexWord( 4, 1 )])) 155 ) { 156 remPtr = altRemPtr; 157 } 158 if ( remPtr[indexWordHi( 4 )] & 0x80000000 ) { 159 signRem = ! signRem; 160 softfloat_negX128M( remPtr ); 161 } 162 remPtr -= indexMultiwordLo( 5, 4 ); 163 remPtr[indexWordHi( 5 )] = 0; 164 softfloat_normRoundPackMToF128M( signRem, expB + 18, remPtr, zWPtr ); 165 return; 166 /*------------------------------------------------------------------------ 167 *------------------------------------------------------------------------*/ 168 invalid: 169 softfloat_invalidF128M( zWPtr ); 170 return; 171 /*------------------------------------------------------------------------ 172 *------------------------------------------------------------------------*/ 173 copyA: 174 zWPtr[indexWordHi( 4 )] = uiA96; 175 zWPtr[indexWord( 4, 2 )] = aWPtr[indexWord( 4, 2 )]; 176 zWPtr[indexWord( 4, 1 )] = aWPtr[indexWord( 4, 1 )]; 177 zWPtr[indexWord( 4, 0 )] = aWPtr[indexWord( 4, 0 )]; 178 179 } 180 181 #endif 182 183