1 2 /*============================================================================ 3 4 This C source file is part of the SoftFloat IEEE Floating-Point Arithmetic 5 Package, Release 3a, 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 float64_t f64_mul( float64_t a, float64_t b ) 45 { 46 union ui64_f64 uA; 47 uint_fast64_t uiA; 48 bool signA; 49 int_fast16_t expA; 50 uint_fast64_t sigA; 51 union ui64_f64 uB; 52 uint_fast64_t uiB; 53 bool signB; 54 int_fast16_t expB; 55 uint_fast64_t sigB; 56 bool signZ; 57 uint_fast64_t magBits; 58 struct exp16_sig64 normExpSig; 59 int_fast16_t expZ; 60 #ifdef SOFTFLOAT_FAST_INT64 61 struct uint128 sig128Z; 62 #else 63 uint32_t sig128Z[4]; 64 #endif 65 uint_fast64_t sigZ, uiZ; 66 union ui64_f64 uZ; 67 68 /*------------------------------------------------------------------------ 69 *------------------------------------------------------------------------*/ 70 uA.f = a; 71 uiA = uA.ui; 72 signA = signF64UI( uiA ); 73 expA = expF64UI( uiA ); 74 sigA = fracF64UI( uiA ); 75 uB.f = b; 76 uiB = uB.ui; 77 signB = signF64UI( uiB ); 78 expB = expF64UI( uiB ); 79 sigB = fracF64UI( uiB ); 80 signZ = signA ^ signB; 81 /*------------------------------------------------------------------------ 82 *------------------------------------------------------------------------*/ 83 if ( expA == 0x7FF ) { 84 if ( sigA || ((expB == 0x7FF) && sigB) ) goto propagateNaN; 85 magBits = expB | sigB; 86 goto infArg; 87 } 88 if ( expB == 0x7FF ) { 89 if ( sigB ) goto propagateNaN; 90 magBits = expA | sigA; 91 goto infArg; 92 } 93 /*------------------------------------------------------------------------ 94 *------------------------------------------------------------------------*/ 95 if ( ! expA ) { 96 if ( ! sigA ) goto zero; 97 normExpSig = softfloat_normSubnormalF64Sig( sigA ); 98 expA = normExpSig.exp; 99 sigA = normExpSig.sig; 100 } 101 if ( ! expB ) { 102 if ( ! sigB ) goto zero; 103 normExpSig = softfloat_normSubnormalF64Sig( sigB ); 104 expB = normExpSig.exp; 105 sigB = normExpSig.sig; 106 } 107 /*------------------------------------------------------------------------ 108 *------------------------------------------------------------------------*/ 109 expZ = expA + expB - 0x3FF; 110 sigA = (sigA | UINT64_C( 0x0010000000000000 ))<<10; 111 sigB = (sigB | UINT64_C( 0x0010000000000000 ))<<11; 112 #ifdef SOFTFLOAT_FAST_INT64 113 sig128Z = softfloat_mul64To128( sigA, sigB ); 114 sigZ = sig128Z.v64 | (sig128Z.v0 != 0); 115 #else 116 softfloat_mul64To128M( sigA, sigB, sig128Z ); 117 sigZ = 118 (uint64_t) sig128Z[indexWord( 4, 3 )]<<32 | sig128Z[indexWord( 4, 2 )]; 119 if ( sig128Z[indexWord( 4, 1 )] || sig128Z[indexWord( 4, 0 )] ) sigZ |= 1; 120 #endif 121 if ( sigZ < UINT64_C( 0x4000000000000000 ) ) { 122 --expZ; 123 sigZ <<= 1; 124 } 125 return softfloat_roundPackToF64( signZ, expZ, sigZ ); 126 /*------------------------------------------------------------------------ 127 *------------------------------------------------------------------------*/ 128 propagateNaN: 129 uiZ = softfloat_propagateNaNF64UI( uiA, uiB ); 130 goto uiZ; 131 /*------------------------------------------------------------------------ 132 *------------------------------------------------------------------------*/ 133 infArg: 134 if ( ! magBits ) { 135 softfloat_raiseFlags( softfloat_flag_invalid ); 136 uiZ = defaultNaNF64UI; 137 } else { 138 uiZ = packToF64UI( signZ, 0x7FF, 0 ); 139 } 140 goto uiZ; 141 /*------------------------------------------------------------------------ 142 *------------------------------------------------------------------------*/ 143 zero: 144 uiZ = packToF64UI( signZ, 0, 0 ); 145 uiZ: 146 uZ.ui = uiZ; 147 return uZ.f; 148 149 } 150 151