1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3 * MIPS floating point support
4 * Copyright (C) 1994-2000 Algorithmics Ltd.
5 *
6 * Nov 7, 2000
7 * Modification to allow integration with Linux kernel
8 *
9 * Kevin D. Kissell, kevink@mips.com and Carsten Langgard, carstenl@mips.com
10 * Copyright (C) 2000 MIPS Technologies, Inc. All rights reserved.
11 */
12 #ifndef __ARCH_MIPS_MATH_EMU_IEEE754_H
13 #define __ARCH_MIPS_MATH_EMU_IEEE754_H
14
15 #include <linux/compiler.h>
16 #include <asm/byteorder.h>
17 #include <linux/kernel.h>
18 #include <linux/types.h>
19 #include <linux/sched.h>
20 #include <asm/bitfield.h>
21
22 union ieee754dp {
23 struct {
24 __BITFIELD_FIELD(unsigned int sign:1,
25 __BITFIELD_FIELD(unsigned int bexp:11,
26 __BITFIELD_FIELD(u64 mant:52,
27 ;)))
28 };
29 u64 bits;
30 };
31
32 union ieee754sp {
33 struct {
34 __BITFIELD_FIELD(unsigned sign:1,
35 __BITFIELD_FIELD(unsigned bexp:8,
36 __BITFIELD_FIELD(unsigned mant:23,
37 ;)))
38 };
39 u32 bits;
40 };
41
42 /*
43 * single precision (often aka float)
44 */
45 int ieee754sp_class(union ieee754sp x);
46
47 union ieee754sp ieee754sp_abs(union ieee754sp x);
48 union ieee754sp ieee754sp_neg(union ieee754sp x);
49
50 union ieee754sp ieee754sp_add(union ieee754sp x, union ieee754sp y);
51 union ieee754sp ieee754sp_sub(union ieee754sp x, union ieee754sp y);
52 union ieee754sp ieee754sp_mul(union ieee754sp x, union ieee754sp y);
53 union ieee754sp ieee754sp_div(union ieee754sp x, union ieee754sp y);
54
55 union ieee754sp ieee754sp_fint(int x);
56 union ieee754sp ieee754sp_flong(s64 x);
57 union ieee754sp ieee754sp_fdp(union ieee754dp x);
58 union ieee754sp ieee754sp_rint(union ieee754sp x);
59
60 int ieee754sp_tint(union ieee754sp x);
61 s64 ieee754sp_tlong(union ieee754sp x);
62
63 int ieee754sp_cmp(union ieee754sp x, union ieee754sp y, int cop, int sig);
64
65 union ieee754sp ieee754sp_sqrt(union ieee754sp x);
66
67 union ieee754sp ieee754sp_maddf(union ieee754sp z, union ieee754sp x,
68 union ieee754sp y);
69 union ieee754sp ieee754sp_msubf(union ieee754sp z, union ieee754sp x,
70 union ieee754sp y);
71 int ieee754sp_2008class(union ieee754sp x);
72 union ieee754sp ieee754sp_fmin(union ieee754sp x, union ieee754sp y);
73 union ieee754sp ieee754sp_fmina(union ieee754sp x, union ieee754sp y);
74 union ieee754sp ieee754sp_fmax(union ieee754sp x, union ieee754sp y);
75 union ieee754sp ieee754sp_fmaxa(union ieee754sp x, union ieee754sp y);
76
77 /*
78 * double precision (often aka double)
79 */
80 int ieee754dp_class(union ieee754dp x);
81
82 union ieee754dp ieee754dp_add(union ieee754dp x, union ieee754dp y);
83 union ieee754dp ieee754dp_sub(union ieee754dp x, union ieee754dp y);
84 union ieee754dp ieee754dp_mul(union ieee754dp x, union ieee754dp y);
85 union ieee754dp ieee754dp_div(union ieee754dp x, union ieee754dp y);
86
87 union ieee754dp ieee754dp_abs(union ieee754dp x);
88 union ieee754dp ieee754dp_neg(union ieee754dp x);
89
90 union ieee754dp ieee754dp_fint(int x);
91 union ieee754dp ieee754dp_flong(s64 x);
92 union ieee754dp ieee754dp_fsp(union ieee754sp x);
93 union ieee754dp ieee754dp_rint(union ieee754dp x);
94
95 int ieee754dp_tint(union ieee754dp x);
96 s64 ieee754dp_tlong(union ieee754dp x);
97
98 int ieee754dp_cmp(union ieee754dp x, union ieee754dp y, int cop, int sig);
99
100 union ieee754dp ieee754dp_sqrt(union ieee754dp x);
101
102 union ieee754dp ieee754dp_maddf(union ieee754dp z, union ieee754dp x,
103 union ieee754dp y);
104 union ieee754dp ieee754dp_msubf(union ieee754dp z, union ieee754dp x,
105 union ieee754dp y);
106 int ieee754dp_2008class(union ieee754dp x);
107 union ieee754dp ieee754dp_fmin(union ieee754dp x, union ieee754dp y);
108 union ieee754dp ieee754dp_fmina(union ieee754dp x, union ieee754dp y);
109 union ieee754dp ieee754dp_fmax(union ieee754dp x, union ieee754dp y);
110 union ieee754dp ieee754dp_fmaxa(union ieee754dp x, union ieee754dp y);
111
112
113 /* 5 types of floating point number
114 */
115 enum {
116 IEEE754_CLASS_NORM = 0x00,
117 IEEE754_CLASS_ZERO = 0x01,
118 IEEE754_CLASS_DNORM = 0x02,
119 IEEE754_CLASS_INF = 0x03,
120 IEEE754_CLASS_SNAN = 0x04,
121 IEEE754_CLASS_QNAN = 0x05,
122 };
123
124 /* exception numbers */
125 #define IEEE754_INEXACT 0x01
126 #define IEEE754_UNDERFLOW 0x02
127 #define IEEE754_OVERFLOW 0x04
128 #define IEEE754_ZERO_DIVIDE 0x08
129 #define IEEE754_INVALID_OPERATION 0x10
130
131 /* cmp operators
132 */
133 #define IEEE754_CLT 0x01
134 #define IEEE754_CEQ 0x02
135 #define IEEE754_CGT 0x04
136 #define IEEE754_CUN 0x08
137
138 /*
139 * The control status register
140 */
141 struct _ieee754_csr {
142 __BITFIELD_FIELD(unsigned fcc:7, /* condition[7:1] */
143 __BITFIELD_FIELD(unsigned nod:1, /* set 1 for no denormals */
144 __BITFIELD_FIELD(unsigned c:1, /* condition[0] */
145 __BITFIELD_FIELD(unsigned pad0:3,
146 __BITFIELD_FIELD(unsigned abs2008:1, /* IEEE 754-2008 ABS/NEG.fmt */
147 __BITFIELD_FIELD(unsigned nan2008:1, /* IEEE 754-2008 NaN mode */
148 __BITFIELD_FIELD(unsigned cx:6, /* exceptions this operation */
149 __BITFIELD_FIELD(unsigned mx:5, /* exception enable mask */
150 __BITFIELD_FIELD(unsigned sx:5, /* exceptions total */
151 __BITFIELD_FIELD(unsigned rm:2, /* current rounding mode */
152 ;))))))))))
153 };
154 #define ieee754_csr (*(struct _ieee754_csr *)(¤t->thread.fpu.fcr31))
155
ieee754_getrm(void)156 static inline unsigned int ieee754_getrm(void)
157 {
158 return (ieee754_csr.rm);
159 }
160
ieee754_setrm(unsigned int rm)161 static inline unsigned int ieee754_setrm(unsigned int rm)
162 {
163 return (ieee754_csr.rm = rm);
164 }
165
166 /*
167 * get current exceptions
168 */
ieee754_getcx(void)169 static inline unsigned int ieee754_getcx(void)
170 {
171 return (ieee754_csr.cx);
172 }
173
174 /* test for current exception condition
175 */
ieee754_cxtest(unsigned int n)176 static inline int ieee754_cxtest(unsigned int n)
177 {
178 return (ieee754_csr.cx & n);
179 }
180
181 /*
182 * get sticky exceptions
183 */
ieee754_getsx(void)184 static inline unsigned int ieee754_getsx(void)
185 {
186 return (ieee754_csr.sx);
187 }
188
189 /* clear sticky conditions
190 */
ieee754_clrsx(void)191 static inline unsigned int ieee754_clrsx(void)
192 {
193 return (ieee754_csr.sx = 0);
194 }
195
196 /* test for sticky exception condition
197 */
ieee754_sxtest(unsigned int n)198 static inline int ieee754_sxtest(unsigned int n)
199 {
200 return (ieee754_csr.sx & n);
201 }
202
203 /* debugging */
204 union ieee754sp ieee754sp_dump(char *s, union ieee754sp x);
205 union ieee754dp ieee754dp_dump(char *s, union ieee754dp x);
206
207 #define IEEE754_SPCVAL_PZERO 0 /* +0.0 */
208 #define IEEE754_SPCVAL_NZERO 1 /* -0.0 */
209 #define IEEE754_SPCVAL_PONE 2 /* +1.0 */
210 #define IEEE754_SPCVAL_NONE 3 /* -1.0 */
211 #define IEEE754_SPCVAL_PTEN 4 /* +10.0 */
212 #define IEEE754_SPCVAL_NTEN 5 /* -10.0 */
213 #define IEEE754_SPCVAL_PINFINITY 6 /* +inf */
214 #define IEEE754_SPCVAL_NINFINITY 7 /* -inf */
215 #define IEEE754_SPCVAL_INDEF_LEG 8 /* legacy quiet NaN */
216 #define IEEE754_SPCVAL_INDEF_2008 9 /* IEEE 754-2008 quiet NaN */
217 #define IEEE754_SPCVAL_PMAX 10 /* +max norm */
218 #define IEEE754_SPCVAL_NMAX 11 /* -max norm */
219 #define IEEE754_SPCVAL_PMIN 12 /* +min norm */
220 #define IEEE754_SPCVAL_NMIN 13 /* -min norm */
221 #define IEEE754_SPCVAL_PMIND 14 /* +min denorm */
222 #define IEEE754_SPCVAL_NMIND 15 /* -min denorm */
223 #define IEEE754_SPCVAL_P1E31 16 /* + 1.0e31 */
224 #define IEEE754_SPCVAL_P1E63 17 /* + 1.0e63 */
225
226 extern const union ieee754dp __ieee754dp_spcvals[];
227 extern const union ieee754sp __ieee754sp_spcvals[];
228 #define ieee754dp_spcvals ((const union ieee754dp *)__ieee754dp_spcvals)
229 #define ieee754sp_spcvals ((const union ieee754sp *)__ieee754sp_spcvals)
230
231 /*
232 * Return infinity with given sign
233 */
234 #define ieee754dp_inf(sn) (ieee754dp_spcvals[IEEE754_SPCVAL_PINFINITY+(sn)])
235 #define ieee754dp_zero(sn) (ieee754dp_spcvals[IEEE754_SPCVAL_PZERO+(sn)])
236 #define ieee754dp_one(sn) (ieee754dp_spcvals[IEEE754_SPCVAL_PONE+(sn)])
237 #define ieee754dp_ten(sn) (ieee754dp_spcvals[IEEE754_SPCVAL_PTEN+(sn)])
238 #define ieee754dp_indef() (ieee754dp_spcvals[IEEE754_SPCVAL_INDEF_LEG + \
239 ieee754_csr.nan2008])
240 #define ieee754dp_max(sn) (ieee754dp_spcvals[IEEE754_SPCVAL_PMAX+(sn)])
241 #define ieee754dp_min(sn) (ieee754dp_spcvals[IEEE754_SPCVAL_PMIN+(sn)])
242 #define ieee754dp_mind(sn) (ieee754dp_spcvals[IEEE754_SPCVAL_PMIND+(sn)])
243 #define ieee754dp_1e31() (ieee754dp_spcvals[IEEE754_SPCVAL_P1E31])
244 #define ieee754dp_1e63() (ieee754dp_spcvals[IEEE754_SPCVAL_P1E63])
245
246 #define ieee754sp_inf(sn) (ieee754sp_spcvals[IEEE754_SPCVAL_PINFINITY+(sn)])
247 #define ieee754sp_zero(sn) (ieee754sp_spcvals[IEEE754_SPCVAL_PZERO+(sn)])
248 #define ieee754sp_one(sn) (ieee754sp_spcvals[IEEE754_SPCVAL_PONE+(sn)])
249 #define ieee754sp_ten(sn) (ieee754sp_spcvals[IEEE754_SPCVAL_PTEN+(sn)])
250 #define ieee754sp_indef() (ieee754sp_spcvals[IEEE754_SPCVAL_INDEF_LEG + \
251 ieee754_csr.nan2008])
252 #define ieee754sp_max(sn) (ieee754sp_spcvals[IEEE754_SPCVAL_PMAX+(sn)])
253 #define ieee754sp_min(sn) (ieee754sp_spcvals[IEEE754_SPCVAL_PMIN+(sn)])
254 #define ieee754sp_mind(sn) (ieee754sp_spcvals[IEEE754_SPCVAL_PMIND+(sn)])
255 #define ieee754sp_1e31() (ieee754sp_spcvals[IEEE754_SPCVAL_P1E31])
256 #define ieee754sp_1e63() (ieee754sp_spcvals[IEEE754_SPCVAL_P1E63])
257
258 /*
259 * Indefinite integer value
260 */
ieee754si_indef(void)261 static inline int ieee754si_indef(void)
262 {
263 return ieee754_csr.nan2008 ? 0 : INT_MAX;
264 }
265
ieee754di_indef(void)266 static inline s64 ieee754di_indef(void)
267 {
268 return ieee754_csr.nan2008 ? 0 : S64_MAX;
269 }
270
271 /*
272 * Overflow integer value
273 */
ieee754si_overflow(int xs)274 static inline int ieee754si_overflow(int xs)
275 {
276 return ieee754_csr.nan2008 && xs ? INT_MIN : INT_MAX;
277 }
278
ieee754di_overflow(int xs)279 static inline s64 ieee754di_overflow(int xs)
280 {
281 return ieee754_csr.nan2008 && xs ? S64_MIN : S64_MAX;
282 }
283
284 /* result types for xctx.rt */
285 #define IEEE754_RT_SP 0
286 #define IEEE754_RT_DP 1
287 #define IEEE754_RT_XP 2
288 #define IEEE754_RT_SI 3
289 #define IEEE754_RT_DI 4
290
291 /* compat */
292 #define ieee754dp_fix(x) ieee754dp_tint(x)
293 #define ieee754sp_fix(x) ieee754sp_tint(x)
294
295 #endif /* __ARCH_MIPS_MATH_EMU_IEEE754_H */
296