2 /*============================================================================
4 This C source file is part of the SoftFloat IEEE Floating-Point Arithmetic
5 Package, Release 3d, by John R. Hauser.
7 Copyright 2011, 2012, 2013, 2014 The Regents of the University of California.
10 Redistribution and use in source and binary forms, with or without
11 modification, are permitted provided that the following conditions are met:
13 1. Redistributions of source code must retain the above copyright notice,
14 this list of conditions, and the following disclaimer.
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.
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.
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.
35 =============================================================================*/
40 #include "internals.h"
41 #include "specialize.h"
42 #include "softfloat.h"
44 float128_t
f128_div( float128_t a
, float128_t b
)
47 uint_fast64_t uiA64
, uiA0
;
52 uint_fast64_t uiB64
, uiB0
;
57 struct exp32_sig128 normExpSig
;
60 uint_fast32_t recip32
;
66 uint_fast64_t sigZExtra
;
67 struct uint128 sigZ
, uiZ
;
70 /*------------------------------------------------------------------------
71 *------------------------------------------------------------------------*/
75 signA
= signF128UI64( uiA64
);
76 expA
= expF128UI64( uiA64
);
77 sigA
.v64
= fracF128UI64( uiA64
);
82 signB
= signF128UI64( uiB64
);
83 expB
= expF128UI64( uiB64
);
84 sigB
.v64
= fracF128UI64( uiB64
);
86 signZ
= signA
^ signB
;
87 /*------------------------------------------------------------------------
88 *------------------------------------------------------------------------*/
89 if ( expA
== 0x7FFF ) {
90 if ( sigA
.v64
| sigA
.v0
) goto propagateNaN
;
91 if ( expB
== 0x7FFF ) {
92 if ( sigB
.v64
| sigB
.v0
) goto propagateNaN
;
97 if ( expB
== 0x7FFF ) {
98 if ( sigB
.v64
| sigB
.v0
) goto propagateNaN
;
101 /*------------------------------------------------------------------------
102 *------------------------------------------------------------------------*/
104 if ( ! (sigB
.v64
| sigB
.v0
) ) {
105 if ( ! (expA
| sigA
.v64
| sigA
.v0
) ) goto invalid
;
106 softfloat_raiseFlags( softfloat_flag_infinite
);
109 normExpSig
= softfloat_normSubnormalF128Sig( sigB
.v64
, sigB
.v0
);
110 expB
= normExpSig
.exp
;
111 sigB
= normExpSig
.sig
;
114 if ( ! (sigA
.v64
| sigA
.v0
) ) goto zero
;
115 normExpSig
= softfloat_normSubnormalF128Sig( sigA
.v64
, sigA
.v0
);
116 expA
= normExpSig
.exp
;
117 sigA
= normExpSig
.sig
;
119 /*------------------------------------------------------------------------
120 *------------------------------------------------------------------------*/
121 expZ
= expA
- expB
+ 0x3FFE;
122 sigA
.v64
|= UINT64_C( 0x0001000000000000 );
123 sigB
.v64
|= UINT64_C( 0x0001000000000000 );
125 if ( softfloat_lt128( sigA
.v64
, sigA
.v0
, sigB
.v64
, sigB
.v0
) ) {
127 rem
= softfloat_add128( sigA
.v64
, sigA
.v0
, sigA
.v64
, sigA
.v0
);
129 recip32
= softfloat_approxRecip32_1( sigB
.v64
>>17 );
132 q64
= (uint_fast64_t) (uint32_t) (rem
.v64
>>19) * recip32
;
133 q
= (q64
+ 0x80000000)>>32;
136 rem
= softfloat_shortShiftLeft128( rem
.v64
, rem
.v0
, 29 );
137 term
= softfloat_mul128By32( sigB
.v64
, sigB
.v0
, q
);
138 rem
= softfloat_sub128( rem
.v64
, rem
.v0
, term
.v64
, term
.v0
);
139 if ( rem
.v64
& UINT64_C( 0x8000000000000000 ) ) {
141 rem
= softfloat_add128( rem
.v64
, rem
.v0
, sigB
.v64
, sigB
.v0
);
145 /*------------------------------------------------------------------------
146 *------------------------------------------------------------------------*/
147 if ( ((q
+ 1) & 7) < 2 ) {
148 rem
= softfloat_shortShiftLeft128( rem
.v64
, rem
.v0
, 29 );
149 term
= softfloat_mul128By32( sigB
.v64
, sigB
.v0
, q
);
150 rem
= softfloat_sub128( rem
.v64
, rem
.v0
, term
.v64
, term
.v0
);
151 if ( rem
.v64
& UINT64_C( 0x8000000000000000 ) ) {
153 rem
= softfloat_add128( rem
.v64
, rem
.v0
, sigB
.v64
, sigB
.v0
);
154 } else if ( softfloat_le128( sigB
.v64
, sigB
.v0
, rem
.v64
, rem
.v0
) ) {
156 rem
= softfloat_sub128( rem
.v64
, rem
.v0
, sigB
.v64
, sigB
.v0
);
158 if ( rem
.v64
| rem
.v0
) q
|= 1;
160 /*------------------------------------------------------------------------
161 *------------------------------------------------------------------------*/
162 sigZExtra
= (uint64_t) ((uint_fast64_t) q
<<60);
163 term
= softfloat_shortShiftLeft128( 0, qs
[1], 54 );
166 (uint_fast64_t) qs
[2]<<19, ((uint_fast64_t) qs
[0]<<25) + (q
>>4),
170 softfloat_roundPackToF128( signZ
, expZ
, sigZ
.v64
, sigZ
.v0
, sigZExtra
);
171 /*------------------------------------------------------------------------
172 *------------------------------------------------------------------------*/
174 uiZ
= softfloat_propagateNaNF128UI( uiA64
, uiA0
, uiB64
, uiB0
);
176 /*------------------------------------------------------------------------
177 *------------------------------------------------------------------------*/
179 softfloat_raiseFlags( softfloat_flag_invalid
);
180 uiZ
.v64
= defaultNaNF128UI64
;
181 uiZ
.v0
= defaultNaNF128UI0
;
183 /*------------------------------------------------------------------------
184 *------------------------------------------------------------------------*/
186 uiZ
.v64
= packToF128UI64( signZ
, 0x7FFF, 0 );
188 /*------------------------------------------------------------------------
189 *------------------------------------------------------------------------*/
191 uiZ
.v64
= packToF128UI64( signZ
, 0, 0 );