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
extF80_mul(extFloat80_t a,extFloat80_t b)44 extFloat80_t extF80_mul( extFloat80_t a, extFloat80_t b )
45 {
46 union { struct extFloat80M s; extFloat80_t f; } uA;
47 uint_fast16_t uiA64;
48 uint_fast64_t uiA0;
49 bool signA;
50 int_fast32_t expA;
51 uint_fast64_t sigA;
52 union { struct extFloat80M s; extFloat80_t f; } uB;
53 uint_fast16_t uiB64;
54 uint_fast64_t uiB0;
55 bool signB;
56 int_fast32_t expB;
57 uint_fast64_t sigB;
58 bool signZ;
59 uint_fast64_t magBits;
60 struct exp32_sig64 normExpSig;
61 int_fast32_t expZ;
62 struct uint128 sig128Z, uiZ;
63 uint_fast16_t uiZ64;
64 uint_fast64_t uiZ0;
65 union { struct extFloat80M s; extFloat80_t f; } uZ;
66
67 /*------------------------------------------------------------------------
68 *------------------------------------------------------------------------*/
69 uA.f = a;
70 uiA64 = uA.s.signExp;
71 uiA0 = uA.s.signif;
72 signA = signExtF80UI64( uiA64 );
73 expA = expExtF80UI64( uiA64 );
74 sigA = uiA0;
75 uB.f = b;
76 uiB64 = uB.s.signExp;
77 uiB0 = uB.s.signif;
78 signB = signExtF80UI64( uiB64 );
79 expB = expExtF80UI64( uiB64 );
80 sigB = uiB0;
81 signZ = signA ^ signB;
82 /*------------------------------------------------------------------------
83 *------------------------------------------------------------------------*/
84 if ( expA == 0x7FFF ) {
85 if (
86 (sigA & UINT64_C( 0x7FFFFFFFFFFFFFFF ))
87 || ((expB == 0x7FFF) && (sigB & UINT64_C( 0x7FFFFFFFFFFFFFFF )))
88 ) {
89 goto propagateNaN;
90 }
91 magBits = expB | sigB;
92 goto infArg;
93 }
94 if ( expB == 0x7FFF ) {
95 if ( sigB & UINT64_C( 0x7FFFFFFFFFFFFFFF ) ) goto propagateNaN;
96 magBits = expA | sigA;
97 goto infArg;
98 }
99 /*------------------------------------------------------------------------
100 *------------------------------------------------------------------------*/
101 if ( ! expA ) expA = 1;
102 if ( ! (sigA & UINT64_C( 0x8000000000000000 )) ) {
103 if ( ! sigA ) goto zero;
104 normExpSig = softfloat_normSubnormalExtF80Sig( sigA );
105 expA += normExpSig.exp;
106 sigA = normExpSig.sig;
107 }
108 if ( ! expB ) expB = 1;
109 if ( ! (sigB & UINT64_C( 0x8000000000000000 )) ) {
110 if ( ! sigB ) goto zero;
111 normExpSig = softfloat_normSubnormalExtF80Sig( sigB );
112 expB += normExpSig.exp;
113 sigB = normExpSig.sig;
114 }
115 /*------------------------------------------------------------------------
116 *------------------------------------------------------------------------*/
117 expZ = expA + expB - 0x3FFE;
118 sig128Z = softfloat_mul64To128( sigA, sigB );
119 if ( sig128Z.v64 < UINT64_C( 0x8000000000000000 ) ) {
120 --expZ;
121 sig128Z =
122 softfloat_add128(
123 sig128Z.v64, sig128Z.v0, sig128Z.v64, sig128Z.v0 );
124 }
125 return
126 softfloat_roundPackToExtF80(
127 signZ, expZ, sig128Z.v64, sig128Z.v0, extF80_roundingPrecision );
128 /*------------------------------------------------------------------------
129 *------------------------------------------------------------------------*/
130 propagateNaN:
131 uiZ = softfloat_propagateNaNExtF80UI( uiA64, uiA0, uiB64, uiB0 );
132 uiZ64 = uiZ.v64;
133 uiZ0 = uiZ.v0;
134 goto uiZ;
135 /*------------------------------------------------------------------------
136 *------------------------------------------------------------------------*/
137 infArg:
138 if ( ! magBits ) {
139 softfloat_raiseFlags( softfloat_flag_invalid );
140 uiZ64 = defaultNaNExtF80UI64;
141 uiZ0 = defaultNaNExtF80UI0;
142 } else {
143 uiZ64 = packToExtF80UI64( signZ, 0x7FFF );
144 uiZ0 = UINT64_C( 0x8000000000000000 );
145 }
146 goto uiZ;
147 /*------------------------------------------------------------------------
148 *------------------------------------------------------------------------*/
149 zero:
150 uiZ64 = packToExtF80UI64( signZ, 0 );
151 uiZ0 = 0;
152 uiZ:
153 uZ.s.signExp = uiZ64;
154 uZ.s.signif = uiZ0;
155 return uZ.f;
156
157 }
158
159