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_div(const float128_t * aPtr,const float128_t * bPtr,float128_t * zPtr)47 f128M_div( const float128_t *aPtr, const float128_t *bPtr, float128_t *zPtr ) 48 { 49 50 *zPtr = f128_div( *aPtr, *bPtr ); 51 52 } 53 54 #else 55 56 void f128M_div(const float128_t * aPtr,const float128_t * bPtr,float128_t * zPtr)57 f128M_div( const float128_t *aPtr, const float128_t *bPtr, float128_t *zPtr ) 58 { 59 const uint32_t *aWPtr, *bWPtr; 60 uint32_t *zWPtr, uiA96; 61 bool signA; 62 int32_t expA; 63 uint32_t uiB96; 64 bool signB; 65 int32_t expB; 66 bool signZ; 67 uint32_t y[5], sigB[4]; 68 int32_t expZ; 69 uint32_t recip32; 70 int ix; 71 uint64_t q64; 72 uint32_t q, qs[3], uiZ96; 73 74 /*------------------------------------------------------------------------ 75 *------------------------------------------------------------------------*/ 76 aWPtr = (const uint32_t *) aPtr; 77 bWPtr = (const uint32_t *) bPtr; 78 zWPtr = (uint32_t *) zPtr; 79 /*------------------------------------------------------------------------ 80 *------------------------------------------------------------------------*/ 81 uiA96 = aWPtr[indexWordHi( 4 )]; 82 signA = signF128UI96( uiA96 ); 83 expA = expF128UI96( uiA96 ); 84 uiB96 = bWPtr[indexWordHi( 4 )]; 85 signB = signF128UI96( uiB96 ); 86 expB = expF128UI96( uiB96 ); 87 signZ = signA ^ signB; 88 /*------------------------------------------------------------------------ 89 *------------------------------------------------------------------------*/ 90 if ( (expA == 0x7FFF) || (expB == 0x7FFF) ) { 91 if ( softfloat_tryPropagateNaNF128M( aWPtr, bWPtr, zWPtr ) ) return; 92 if ( expA == 0x7FFF ) { 93 if ( expB == 0x7FFF ) goto invalid; 94 goto infinity; 95 } 96 goto zero; 97 } 98 /*------------------------------------------------------------------------ 99 *------------------------------------------------------------------------*/ 100 expA = softfloat_shiftNormSigF128M( aWPtr, 13, y ); 101 expB = softfloat_shiftNormSigF128M( bWPtr, 13, sigB ); 102 if ( expA == -128 ) { 103 if ( expB == -128 ) goto invalid; 104 goto zero; 105 } 106 if ( expB == -128 ) { 107 softfloat_raiseFlags( softfloat_flag_infinite ); 108 goto infinity; 109 } 110 /*------------------------------------------------------------------------ 111 *------------------------------------------------------------------------*/ 112 expZ = expA - expB + 0x3FFE; 113 if ( softfloat_compare128M( y, sigB ) < 0 ) { 114 --expZ; 115 softfloat_add128M( y, y, y ); 116 } 117 recip32 = 118 softfloat_approxRecip32_1( 119 ((uint64_t) sigB[indexWord( 4, 3 )]<<32 | sigB[indexWord( 4, 2 )]) 120 >>30 121 ); 122 ix = 3; 123 for (;;) { 124 q64 = (uint64_t) y[indexWordHi( 4 )] * recip32; 125 q = (q64 + 0x80000000)>>32; 126 --ix; 127 if ( ix < 0 ) break; 128 softfloat_remStep128MBy32( y, 29, sigB, q, y ); 129 if ( y[indexWordHi( 4 )] & 0x80000000 ) { 130 --q; 131 softfloat_add128M( y, sigB, y ); 132 } 133 qs[ix] = q; 134 } 135 /*------------------------------------------------------------------------ 136 *------------------------------------------------------------------------*/ 137 if ( ((q + 1) & 7) < 2 ) { 138 softfloat_remStep128MBy32( y, 29, sigB, q, y ); 139 if ( y[indexWordHi( 4 )] & 0x80000000 ) { 140 --q; 141 softfloat_add128M( y, sigB, y ); 142 } else if ( softfloat_compare128M( sigB, y ) <= 0 ) { 143 ++q; 144 softfloat_sub128M( y, sigB, y ); 145 } 146 if ( 147 y[indexWordLo( 4 )] || y[indexWord( 4, 1 )] 148 || (y[indexWord( 4, 2 )] | y[indexWord( 4, 3 )]) 149 ) { 150 q |= 1; 151 } 152 } 153 /*------------------------------------------------------------------------ 154 *------------------------------------------------------------------------*/ 155 q64 = (uint64_t) q<<28; 156 y[indexWord( 5, 0 )] = q64; 157 q64 = ((uint64_t) qs[0]<<25) + (q64>>32); 158 y[indexWord( 5, 1 )] = q64; 159 q64 = ((uint64_t) qs[1]<<22) + (q64>>32); 160 y[indexWord( 5, 2 )] = q64; 161 q64 = ((uint64_t) qs[2]<<19) + (q64>>32); 162 y[indexWord( 5, 3 )] = q64; 163 y[indexWord( 5, 4 )] = q64>>32; 164 softfloat_roundPackMToF128M( signZ, expZ, y, zWPtr ); 165 return; 166 /*------------------------------------------------------------------------ 167 *------------------------------------------------------------------------*/ 168 invalid: 169 softfloat_invalidF128M( zWPtr ); 170 return; 171 /*------------------------------------------------------------------------ 172 *------------------------------------------------------------------------*/ 173 infinity: 174 uiZ96 = packToF128UI96( signZ, 0x7FFF, 0 ); 175 goto uiZ96; 176 zero: 177 uiZ96 = packToF128UI96( signZ, 0, 0 ); 178 uiZ96: 179 zWPtr[indexWordHi( 4 )] = uiZ96; 180 zWPtr[indexWord( 4, 2 )] = 0; 181 zWPtr[indexWord( 4, 1 )] = 0; 182 zWPtr[indexWord( 4, 0 )] = 0; 183 184 } 185 186 #endif 187 188