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gerrit-public.fairphone.software / kernel / msm-4.9 / 694f6ea0a4e2edd69c1278d4fba77c670276b416 / . / arch / mips / math-emu / sp_fmin.c
blob: c982647df39a20f5bfacf00dd8a55389d1440bea [file] [log] [blame]
Markos Chandras4e9561b2015-08-13 09:56:35 +0200[diff] [blame]1/*
2 * IEEE754 floating point arithmetic
3 * single precision: MIN{,A}.f
4 * MIN : Scalar Floating-Point Minimum
5 * MINA: Scalar Floating-Point argument with Minimum Absolute Value
6 *
7 * MIN.S : FPR[fd] = minNum(FPR[fs],FPR[ft])
8 * MINA.S: FPR[fd] = maxNumMag(FPR[fs],FPR[ft])
9 *
10 * MIPS floating point support
11 * Copyright (C) 2015 Imagination Technologies, Ltd.
12 * Author: Markos Chandras <markos.chandras@imgtec.com>
13 *
14 * This program is free software; you can distribute it and/or modify it
15 * under the terms of the GNU General Public License as published by the
16 * Free Software Foundation; version 2 of the License.
17 */
18
19#include "ieee754sp.h"
20
21union ieee754sp ieee754sp_fmin(union ieee754sp x, union ieee754sp y)
22{
23 COMPXSP;
24 COMPYSP;
25
26 EXPLODEXSP;
27 EXPLODEYSP;
28
29 FLUSHXSP;
30 FLUSHYSP;
31
32 ieee754_clearcx();
33
34 switch (CLPAIR(xc, yc)) {
35 case CLPAIR(IEEE754_CLASS_QNAN, IEEE754_CLASS_SNAN):
36 case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_SNAN):
37 case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_SNAN):
38 case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_SNAN):
39 case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_SNAN):
40 return ieee754sp_nanxcpt(y);
41
42 case CLPAIR(IEEE754_CLASS_SNAN, IEEE754_CLASS_SNAN):
43 case CLPAIR(IEEE754_CLASS_SNAN, IEEE754_CLASS_QNAN):
44 case CLPAIR(IEEE754_CLASS_SNAN, IEEE754_CLASS_ZERO):
45 case CLPAIR(IEEE754_CLASS_SNAN, IEEE754_CLASS_NORM):
46 case CLPAIR(IEEE754_CLASS_SNAN, IEEE754_CLASS_DNORM):
47 case CLPAIR(IEEE754_CLASS_SNAN, IEEE754_CLASS_INF):
48 return ieee754sp_nanxcpt(x);
49
Aleksandar Markovicb2341492017-07-27 18:08:48 +0200[diff] [blame]50 /*
51 * Quiet NaN handling
52 */
53
54 /*
55 * The case of both inputs quiet NaNs
56 */
57 case CLPAIR(IEEE754_CLASS_QNAN, IEEE754_CLASS_QNAN):
58 return x;
59
60 /*
61 * The cases of exactly one input quiet NaN (numbers
62 * are here preferred as returned values to NaNs)
63 */
Markos Chandras4e9561b2015-08-13 09:56:35 +0200[diff] [blame]64 case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_QNAN):
65 case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_QNAN):
66 case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_QNAN):
67 case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_QNAN):
68 return x;
69
Markos Chandras4e9561b2015-08-13 09:56:35 +0200[diff] [blame]70 case CLPAIR(IEEE754_CLASS_QNAN, IEEE754_CLASS_ZERO):
71 case CLPAIR(IEEE754_CLASS_QNAN, IEEE754_CLASS_NORM):
72 case CLPAIR(IEEE754_CLASS_QNAN, IEEE754_CLASS_DNORM):
73 case CLPAIR(IEEE754_CLASS_QNAN, IEEE754_CLASS_INF):
74 return y;
75
76 /*
77 * Infinity and zero handling
78 */
79 case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_ZERO):
80 case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_NORM):
81 case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_DNORM):
82 case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_ZERO):
83 case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_ZERO):
84 return xs ? x : y;
85
86 case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_INF):
87 case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_INF):
88 case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_INF):
89 case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_INF):
90 case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_NORM):
91 case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_DNORM):
92 return ys ? y : x;
93
94 case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_ZERO):
Aleksandar Markovic694f6ea2017-07-27 18:08:49 +0200[diff] [blame^]95 return ieee754sp_zero(xs | ys);
Markos Chandras4e9561b2015-08-13 09:56:35 +0200[diff] [blame]96
97 case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_DNORM):
98 SPDNORMX;
99
100 case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_DNORM):
101 SPDNORMY;
102 break;
103
104 case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_NORM):
105 SPDNORMX;
106 }
107
108 /* Finally get to do some computation */
109
110 assert(xm & SP_HIDDEN_BIT);
111 assert(ym & SP_HIDDEN_BIT);
112
113 /* Compare signs */
114 if (xs > ys)
115 return x;
116 else if (xs < ys)
117 return y;
118
119 /* Compare exponent */
120 if (xe > ye)
121 return y;
122 else if (xe < ye)
123 return x;
124
125 /* Compare mantissa */
126 if (xm <= ym)
127 return x;
128 return y;
129}
130
131union ieee754sp ieee754sp_fmina(union ieee754sp x, union ieee754sp y)
132{
133 COMPXSP;
134 COMPYSP;
135
136 EXPLODEXSP;
137 EXPLODEYSP;
138
139 FLUSHXSP;
140 FLUSHYSP;
141
142 ieee754_clearcx();
143
144 switch (CLPAIR(xc, yc)) {
145 case CLPAIR(IEEE754_CLASS_QNAN, IEEE754_CLASS_SNAN):
146 case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_SNAN):
147 case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_SNAN):
148 case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_SNAN):
149 case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_SNAN):
150 return ieee754sp_nanxcpt(y);
151
152 case CLPAIR(IEEE754_CLASS_SNAN, IEEE754_CLASS_SNAN):
153 case CLPAIR(IEEE754_CLASS_SNAN, IEEE754_CLASS_QNAN):
154 case CLPAIR(IEEE754_CLASS_SNAN, IEEE754_CLASS_ZERO):
155 case CLPAIR(IEEE754_CLASS_SNAN, IEEE754_CLASS_NORM):
156 case CLPAIR(IEEE754_CLASS_SNAN, IEEE754_CLASS_DNORM):
157 case CLPAIR(IEEE754_CLASS_SNAN, IEEE754_CLASS_INF):
158 return ieee754sp_nanxcpt(x);
159
Aleksandar Markovicb2341492017-07-27 18:08:48 +0200[diff] [blame]160 /*
161 * Quiet NaN handling
162 */
163
164 /*
165 * The case of both inputs quiet NaNs
166 */
167 case CLPAIR(IEEE754_CLASS_QNAN, IEEE754_CLASS_QNAN):
168 return x;
169
170 /*
171 * The cases of exactly one input quiet NaN (numbers
172 * are here preferred as returned values to NaNs)
173 */
Markos Chandras4e9561b2015-08-13 09:56:35 +0200[diff] [blame]174 case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_QNAN):
175 case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_QNAN):
176 case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_QNAN):
177 case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_QNAN):
178 return x;
179
Markos Chandras4e9561b2015-08-13 09:56:35 +0200[diff] [blame]180 case CLPAIR(IEEE754_CLASS_QNAN, IEEE754_CLASS_ZERO):
181 case CLPAIR(IEEE754_CLASS_QNAN, IEEE754_CLASS_NORM):
182 case CLPAIR(IEEE754_CLASS_QNAN, IEEE754_CLASS_DNORM):
183 case CLPAIR(IEEE754_CLASS_QNAN, IEEE754_CLASS_INF):
184 return y;
185
186 /*
187 * Infinity and zero handling
188 */
189 case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_ZERO):
190 case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_NORM):
191 case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_DNORM):
192 case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_ZERO):
193 case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_ZERO):
194 return x;
195
196 case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_INF):
197 case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_INF):
198 case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_INF):
199 case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_INF):
200 case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_NORM):
201 case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_DNORM):
202 return y;
203
204 case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_ZERO):
Aleksandar Markovic694f6ea2017-07-27 18:08:49 +0200[diff] [blame^]205 return ieee754sp_zero(xs | ys);
Markos Chandras4e9561b2015-08-13 09:56:35 +0200[diff] [blame]206
207 case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_DNORM):
208 SPDNORMX;
209
210 case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_DNORM):
211 SPDNORMY;
212 break;
213
214 case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_NORM):
215 SPDNORMX;
216 }
217
218 /* Finally get to do some computation */
219
220 assert(xm & SP_HIDDEN_BIT);
221 assert(ym & SP_HIDDEN_BIT);
222
223 /* Compare exponent */
224 if (xe > ye)
225 return y;
226 else if (xe < ye)
227 return x;
228
229 /* Compare mantissa */
230 if (xm <= ym)
231 return x;
232 return y;
233}