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 float32_t f32_mul( float32_t a, float32_t b ) 45 { 46 union ui32_f32 uA; 47 uint_fast32_t uiA; 48 bool signA; 49 int_fast16_t expA; 50 uint_fast32_t sigA; 51 union ui32_f32 uB; 52 uint_fast32_t uiB; 53 bool signB; 54 int_fast16_t expB; 55 uint_fast32_t sigB; 56 bool signZ; 57 uint_fast32_t magBits; 58 struct exp16_sig32 normExpSig; 59 int_fast16_t expZ; 60 uint_fast32_t sigZ, uiZ; 61 union ui32_f32 uZ; 62 63 uA.f = a; 64 uiA = uA.ui; 65 signA = signF32UI( uiA ); 66 expA = expF32UI( uiA ); 67 sigA = fracF32UI( uiA ); 68 uB.f = b; 69 uiB = uB.ui; 70 signB = signF32UI( uiB ); 71 expB = expF32UI( uiB ); 72 sigB = fracF32UI( uiB ); 73 signZ = signA ^ signB; 74 if ( expA == 0xFF ) { 75 if ( sigA || ((expB == 0xFF) && sigB) ) goto propagateNaN; 76 magBits = expB | sigB; 77 goto infArg; 78 } 79 if ( expB == 0xFF ) { 80 if ( sigB ) goto propagateNaN; 81 magBits = expA | sigA; 82 goto infArg; 83 } 84 if ( ! expA ) { 85 if ( ! sigA ) goto zero; 86 normExpSig = softfloat_normSubnormalF32Sig( sigA ); 87 expA = normExpSig.exp; 88 sigA = normExpSig.sig; 89 } 90 if ( ! expB ) { 91 if ( ! sigB ) goto zero; 92 normExpSig = softfloat_normSubnormalF32Sig( sigB ); 93 expB = normExpSig.exp; 94 sigB = normExpSig.sig; 95 } 96 expZ = expA + expB - 0x7F; 97 sigA = (sigA | 0x00800000)<<7; 98 sigB = (sigB | 0x00800000)<<8; 99 sigZ = softfloat_shortShiftRightJam64( (uint_fast64_t) sigA * sigB, 32 ); 100 if ( sigZ < 0x40000000 ) { 101 --expZ; 102 sigZ <<= 1; 103 } 104 return softfloat_roundPackToF32( signZ, expZ, sigZ ); 105 propagateNaN: 106 uiZ = softfloat_propagateNaNF32UI( uiA, uiB ); 107 goto uiZ; 108 infArg: 109 if ( ! magBits ) { 110 softfloat_raiseFlags( softfloat_flag_invalid ); 111 uiZ = defaultNaNF32UI; 112 } else { 113 uiZ = packToF32UI( signZ, 0xFF, 0 ); 114 } 115 goto uiZ; 116 zero: 117 uiZ = packToF32UI( signZ, 0, 0 ); 118 uiZ: 119 uZ.ui = uiZ; 120 return uZ.f; 121 122 } 123 124