Rev 535 | Rev 563 | Go to most recent revision | Details | Compare with Previous | Last modification | View Log | RSS feed
| Rev | Author | Line No. | Line |
|---|---|---|---|
| 535 | cejka | 1 | |
| 2 | /* |
||
| 3 | * Copyright (C) 2005 Josef Cejka |
||
| 4 | * All rights reserved. |
||
| 5 | * |
||
| 6 | * Redistribution and use in source and binary forms, with or without |
||
| 7 | * modification, are permitted provided that the following conditions |
||
| 8 | * are met: |
||
| 9 | * |
||
| 10 | * - Redistributions of source code must retain the above copyright |
||
| 11 | * notice, this list of conditions and the following disclaimer. |
||
| 12 | * - Redistributions in binary form must reproduce the above copyright |
||
| 13 | * notice, this list of conditions and the following disclaimer in the |
||
| 14 | * documentation and/or other materials provided with the distribution. |
||
| 15 | * - The name of the author may not be used to endorse or promote products |
||
| 16 | * derived from this software without specific prior written permission. |
||
| 17 | * |
||
| 18 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR |
||
| 19 | * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
||
| 20 | * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. |
||
| 21 | * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, |
||
| 22 | * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
||
| 23 | * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
||
| 24 | * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
||
| 25 | * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
||
| 26 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF |
||
| 27 | * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
||
| 28 | */ |
||
| 29 | |||
| 30 | #include<softfloat.h> |
||
| 31 | |||
| 542 | cejka | 32 | |
| 33 | float __addsf3(float a, float b) |
||
| 34 | { |
||
| 35 | float32 fa, fb; |
||
| 36 | a.f=a; |
||
| 37 | b.f=b; |
||
| 38 | if (a.parts.sign!=b.parts.sign) return subFloat32(a,b).f; |
||
| 39 | return addFloat32(a,b).f; |
||
| 40 | }; |
||
| 41 | |||
| 42 | float __subsf3(float a, float b) |
||
| 43 | { |
||
| 44 | float32 fa, fb; |
||
| 45 | a.f=a; |
||
| 46 | b.f=b; |
||
| 47 | if (a.parts.sign!=b.parts.sign) return addFloat32(a,b).f; |
||
| 48 | return subFloat32(a,b).f; |
||
| 49 | }; |
||
| 50 | |||
| 51 | float __negsf2(float a) |
||
| 52 | { |
||
| 53 | float32 fa; |
||
| 54 | fa.f=a; |
||
| 55 | fa.parts.sign=!fa.parts.sign; |
||
| 56 | return fa.f; |
||
| 57 | }; |
||
| 58 | |||
| 59 | double __negdf2(double a) |
||
| 60 | { |
||
| 61 | float64 fa; |
||
| 62 | fa.f=a; |
||
| 63 | fa.parts.sign=!fa.parts.sign; |
||
| 64 | return fa.f; |
||
| 65 | }; |
||
| 66 | |||
| 67 | float32 addFloat32(float32 a, float32 b) |
||
| 68 | { |
||
| 69 | __u32 expdiff; |
||
| 70 | __u32 exp1,exp2,mant1,mant2; |
||
| 71 | |||
| 72 | expdiff=a.parts.exp - b.parts.exp; |
||
| 73 | if (expdiff<0) { |
||
| 74 | if (isFloat32NaN(a)) { |
||
| 75 | //TODO: fix it |
||
| 76 | return a; |
||
| 77 | }; |
||
| 78 | |||
| 79 | mant1=b.parts.mantisa; |
||
| 80 | exp1=b.parts.exp; |
||
| 81 | mant2=a.parts.mantisa; |
||
| 82 | exp2=a.parts.exp; |
||
| 83 | expdiff*=-1; |
||
| 84 | } else { |
||
| 85 | if (isFloat32NaN(b)) { |
||
| 86 | //TODO: fix it |
||
| 87 | return b; |
||
| 88 | }; |
||
| 89 | mant1=a.parts.mantisa; |
||
| 90 | exp1=a.parts.exp; |
||
| 91 | mant2=b.parts.mantisa; |
||
| 92 | exp2=b.parts.exp; |
||
| 93 | }; |
||
| 94 | |||
| 95 | // create some space for rounding |
||
| 96 | mant1<<=6; |
||
| 97 | mant2<<=6; |
||
| 98 | |||
| 99 | if (exp1!=0) { |
||
| 100 | mant1|=0x20000000; //add hidden bit |
||
| 101 | }; |
||
| 102 | |||
| 103 | if (exp2==0) { |
||
| 104 | --expdiff; |
||
| 105 | } else { |
||
| 106 | mant2|=0x20000000; //hidden bit |
||
| 107 | }; |
||
| 108 | |||
| 109 | |||
| 110 | if (expdiff>24) { |
||
| 111 | goto done; |
||
| 112 | }; |
||
| 113 | |||
| 114 | mant2>>=expdiff; |
||
| 115 | mant1+=mant2; |
||
| 116 | done: |
||
| 117 | //TODO: round mant1 |
||
| 118 | a.parts.exp=exp1; |
||
| 119 | a.parts.mantisa=mant1>>6; |
||
| 120 | return a; |
||
| 121 | }; |
||
| 122 | |||
| 123 | float32 subFloat32(float32 a, float32 b) |
||
| 124 | { |
||
| 125 | |||
| 126 | |||
| 127 | }; |
||
| 128 | |||
| 129 | inline int isFloat32NaN(float32 f) |
||
| 130 | { /* NaN : exp = 0xff and nonzero mantisa */ |
||
| 131 | float32 fa; |
||
| 132 | fa.f=f; |
||
| 133 | return ((fa.parts.exp==0xFF)&&(fa.parts.mantisa)); |
||
| 134 | }; |
||
| 135 | |||
| 136 | inline int isFloat32SigNaN(float32 f) |
||
| 137 | { /* SigNaN : exp = 0xff mantisa = 1xxxxx..x (binary), where at least one x is nonzero */ |
||
| 138 | float32 fa; |
||
| 139 | fa.f=f; |
||
| 140 | return ((fa.parts.exp==0xFF)&&(fa.parts.mantisa>0x400000)); |
||
| 141 | }; |
||
| 142 |