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 union ieee754sp ieee754sp_madd(union ieee754sp z, union ieee754sp x,
72 union ieee754sp y);
73 union ieee754sp ieee754sp_msub(union ieee754sp z, union ieee754sp x,
74 union ieee754sp y);
75 union ieee754sp ieee754sp_nmadd(union ieee754sp z, union ieee754sp x,
76 union ieee754sp y);
77 union ieee754sp ieee754sp_nmsub(union ieee754sp z, union ieee754sp x,
78 union ieee754sp y);
79 int ieee754sp_2008class(union ieee754sp x);
80 union ieee754sp ieee754sp_fmin(union ieee754sp x, union ieee754sp y);
81 union ieee754sp ieee754sp_fmina(union ieee754sp x, union ieee754sp y);
82 union ieee754sp ieee754sp_fmax(union ieee754sp x, union ieee754sp y);
83 union ieee754sp ieee754sp_fmaxa(union ieee754sp x, union ieee754sp y);
84
85 /*
86 * double precision (often aka double)
87 */
88 int ieee754dp_class(union ieee754dp x);
89
90 union ieee754dp ieee754dp_add(union ieee754dp x, union ieee754dp y);
91 union ieee754dp ieee754dp_sub(union ieee754dp x, union ieee754dp y);
92 union ieee754dp ieee754dp_mul(union ieee754dp x, union ieee754dp y);
93 union ieee754dp ieee754dp_div(union ieee754dp x, union ieee754dp y);
94
95 union ieee754dp ieee754dp_abs(union ieee754dp x);
96 union ieee754dp ieee754dp_neg(union ieee754dp x);
97
98 union ieee754dp ieee754dp_fint(int x);
99 union ieee754dp ieee754dp_flong(s64 x);
100 union ieee754dp ieee754dp_fsp(union ieee754sp x);
101 union ieee754dp ieee754dp_rint(union ieee754dp x);
102
103 int ieee754dp_tint(union ieee754dp x);
104 s64 ieee754dp_tlong(union ieee754dp x);
105
106 int ieee754dp_cmp(union ieee754dp x, union ieee754dp y, int cop, int sig);
107
108 union ieee754dp ieee754dp_sqrt(union ieee754dp x);
109
110 union ieee754dp ieee754dp_maddf(union ieee754dp z, union ieee754dp x,
111 union ieee754dp y);
112 union ieee754dp ieee754dp_msubf(union ieee754dp z, union ieee754dp x,
113 union ieee754dp y);
114 union ieee754dp ieee754dp_madd(union ieee754dp z, union ieee754dp x,
115 union ieee754dp y);
116 union ieee754dp ieee754dp_msub(union ieee754dp z, union ieee754dp x,
117 union ieee754dp y);
118 union ieee754dp ieee754dp_nmadd(union ieee754dp z, union ieee754dp x,
119 union ieee754dp y);
120 union ieee754dp ieee754dp_nmsub(union ieee754dp z, union ieee754dp x,
121 union ieee754dp y);
122 int ieee754dp_2008class(union ieee754dp x);
123 union ieee754dp ieee754dp_fmin(union ieee754dp x, union ieee754dp y);
124 union ieee754dp ieee754dp_fmina(union ieee754dp x, union ieee754dp y);
125 union ieee754dp ieee754dp_fmax(union ieee754dp x, union ieee754dp y);
126 union ieee754dp ieee754dp_fmaxa(union ieee754dp x, union ieee754dp y);
127
128
129 /* 5 types of floating point number
130 */
131 enum {
132 IEEE754_CLASS_NORM = 0x00,
133 IEEE754_CLASS_ZERO = 0x01,
134 IEEE754_CLASS_DNORM = 0x02,
135 IEEE754_CLASS_INF = 0x03,
136 IEEE754_CLASS_SNAN = 0x04,
137 IEEE754_CLASS_QNAN = 0x05,
138 };
139
140 /* exception numbers */
141 #define IEEE754_INEXACT 0x01
142 #define IEEE754_UNDERFLOW 0x02
143 #define IEEE754_OVERFLOW 0x04
144 #define IEEE754_ZERO_DIVIDE 0x08
145 #define IEEE754_INVALID_OPERATION 0x10
146
147 /* cmp operators
148 */
149 #define IEEE754_CLT 0x01
150 #define IEEE754_CEQ 0x02
151 #define IEEE754_CGT 0x04
152 #define IEEE754_CUN 0x08
153
154 /*
155 * The control status register
156 */
157 struct _ieee754_csr {
158 __BITFIELD_FIELD(unsigned fcc:7, /* condition[7:1] */
159 __BITFIELD_FIELD(unsigned nod:1, /* set 1 for no denormals */
160 __BITFIELD_FIELD(unsigned c:1, /* condition[0] */
161 __BITFIELD_FIELD(unsigned pad0:3,
162 __BITFIELD_FIELD(unsigned abs2008:1, /* IEEE 754-2008 ABS/NEG.fmt */
163 __BITFIELD_FIELD(unsigned nan2008:1, /* IEEE 754-2008 NaN mode */
164 __BITFIELD_FIELD(unsigned cx:6, /* exceptions this operation */
165 __BITFIELD_FIELD(unsigned mx:5, /* exception enable mask */
166 __BITFIELD_FIELD(unsigned sx:5, /* exceptions total */
167 __BITFIELD_FIELD(unsigned rm:2, /* current rounding mode */
168 ;))))))))))
169 };
170 #define ieee754_csr (*(struct _ieee754_csr *)(¤t->thread.fpu.fcr31))
171
ieee754_getrm(void)172 static inline unsigned int ieee754_getrm(void)
173 {
174 return (ieee754_csr.rm);
175 }
176
ieee754_setrm(unsigned int rm)177 static inline unsigned int ieee754_setrm(unsigned int rm)
178 {
179 return (ieee754_csr.rm = rm);
180 }
181
182 /*
183 * get current exceptions
184 */
ieee754_getcx(void)185 static inline unsigned int ieee754_getcx(void)
186 {
187 return (ieee754_csr.cx);
188 }
189
190 /* test for current exception condition
191 */
ieee754_cxtest(unsigned int n)192 static inline int ieee754_cxtest(unsigned int n)
193 {
194 return (ieee754_csr.cx & n);
195 }
196
197 /*
198 * get sticky exceptions
199 */
ieee754_getsx(void)200 static inline unsigned int ieee754_getsx(void)
201 {
202 return (ieee754_csr.sx);
203 }
204
205 /* clear sticky conditions
206 */
ieee754_clrsx(void)207 static inline unsigned int ieee754_clrsx(void)
208 {
209 return (ieee754_csr.sx = 0);
210 }
211
212 /* test for sticky exception condition
213 */
ieee754_sxtest(unsigned int n)214 static inline int ieee754_sxtest(unsigned int n)
215 {
216 return (ieee754_csr.sx & n);
217 }
218
219 /* debugging */
220 union ieee754sp ieee754sp_dump(char *s, union ieee754sp x);
221 union ieee754dp ieee754dp_dump(char *s, union ieee754dp x);
222
223 #define IEEE754_SPCVAL_PZERO 0 /* +0.0 */
224 #define IEEE754_SPCVAL_NZERO 1 /* -0.0 */
225 #define IEEE754_SPCVAL_PONE 2 /* +1.0 */
226 #define IEEE754_SPCVAL_NONE 3 /* -1.0 */
227 #define IEEE754_SPCVAL_PTEN 4 /* +10.0 */
228 #define IEEE754_SPCVAL_NTEN 5 /* -10.0 */
229 #define IEEE754_SPCVAL_PINFINITY 6 /* +inf */
230 #define IEEE754_SPCVAL_NINFINITY 7 /* -inf */
231 #define IEEE754_SPCVAL_INDEF_LEG 8 /* legacy quiet NaN */
232 #define IEEE754_SPCVAL_INDEF_2008 9 /* IEEE 754-2008 quiet NaN */
233 #define IEEE754_SPCVAL_PMAX 10 /* +max norm */
234 #define IEEE754_SPCVAL_NMAX 11 /* -max norm */
235 #define IEEE754_SPCVAL_PMIN 12 /* +min norm */
236 #define IEEE754_SPCVAL_NMIN 13 /* -min norm */
237 #define IEEE754_SPCVAL_PMIND 14 /* +min denorm */
238 #define IEEE754_SPCVAL_NMIND 15 /* -min denorm */
239 #define IEEE754_SPCVAL_P1E31 16 /* + 1.0e31 */
240 #define IEEE754_SPCVAL_P1E63 17 /* + 1.0e63 */
241
242 extern const union ieee754dp __ieee754dp_spcvals[];
243 extern const union ieee754sp __ieee754sp_spcvals[];
244 #define ieee754dp_spcvals ((const union ieee754dp *)__ieee754dp_spcvals)
245 #define ieee754sp_spcvals ((const union ieee754sp *)__ieee754sp_spcvals)
246
247 /*
248 * Return infinity with given sign
249 */
250 #define ieee754dp_inf(sn) (ieee754dp_spcvals[IEEE754_SPCVAL_PINFINITY+(sn)])
251 #define ieee754dp_zero(sn) (ieee754dp_spcvals[IEEE754_SPCVAL_PZERO+(sn)])
252 #define ieee754dp_one(sn) (ieee754dp_spcvals[IEEE754_SPCVAL_PONE+(sn)])
253 #define ieee754dp_ten(sn) (ieee754dp_spcvals[IEEE754_SPCVAL_PTEN+(sn)])
254 #define ieee754dp_indef() (ieee754dp_spcvals[IEEE754_SPCVAL_INDEF_LEG + \
255 ieee754_csr.nan2008])
256 #define ieee754dp_max(sn) (ieee754dp_spcvals[IEEE754_SPCVAL_PMAX+(sn)])
257 #define ieee754dp_min(sn) (ieee754dp_spcvals[IEEE754_SPCVAL_PMIN+(sn)])
258 #define ieee754dp_mind(sn) (ieee754dp_spcvals[IEEE754_SPCVAL_PMIND+(sn)])
259 #define ieee754dp_1e31() (ieee754dp_spcvals[IEEE754_SPCVAL_P1E31])
260 #define ieee754dp_1e63() (ieee754dp_spcvals[IEEE754_SPCVAL_P1E63])
261
262 #define ieee754sp_inf(sn) (ieee754sp_spcvals[IEEE754_SPCVAL_PINFINITY+(sn)])
263 #define ieee754sp_zero(sn) (ieee754sp_spcvals[IEEE754_SPCVAL_PZERO+(sn)])
264 #define ieee754sp_one(sn) (ieee754sp_spcvals[IEEE754_SPCVAL_PONE+(sn)])
265 #define ieee754sp_ten(sn) (ieee754sp_spcvals[IEEE754_SPCVAL_PTEN+(sn)])
266 #define ieee754sp_indef() (ieee754sp_spcvals[IEEE754_SPCVAL_INDEF_LEG + \
267 ieee754_csr.nan2008])
268 #define ieee754sp_max(sn) (ieee754sp_spcvals[IEEE754_SPCVAL_PMAX+(sn)])
269 #define ieee754sp_min(sn) (ieee754sp_spcvals[IEEE754_SPCVAL_PMIN+(sn)])
270 #define ieee754sp_mind(sn) (ieee754sp_spcvals[IEEE754_SPCVAL_PMIND+(sn)])
271 #define ieee754sp_1e31() (ieee754sp_spcvals[IEEE754_SPCVAL_P1E31])
272 #define ieee754sp_1e63() (ieee754sp_spcvals[IEEE754_SPCVAL_P1E63])
273
274 /*
275 * Indefinite integer value
276 */
ieee754si_indef(void)277 static inline int ieee754si_indef(void)
278 {
279 return ieee754_csr.nan2008 ? 0 : INT_MAX;
280 }
281
ieee754di_indef(void)282 static inline s64 ieee754di_indef(void)
283 {
284 return ieee754_csr.nan2008 ? 0 : S64_MAX;
285 }
286
287 /*
288 * Overflow integer value
289 */
ieee754si_overflow(int xs)290 static inline int ieee754si_overflow(int xs)
291 {
292 return ieee754_csr.nan2008 && xs ? INT_MIN : INT_MAX;
293 }
294
ieee754di_overflow(int xs)295 static inline s64 ieee754di_overflow(int xs)
296 {
297 return ieee754_csr.nan2008 && xs ? S64_MIN : S64_MAX;
298 }
299
300 /* result types for xctx.rt */
301 #define IEEE754_RT_SP 0
302 #define IEEE754_RT_DP 1
303 #define IEEE754_RT_XP 2
304 #define IEEE754_RT_SI 3
305 #define IEEE754_RT_DI 4
306
307 /* compat */
308 #define ieee754dp_fix(x) ieee754dp_tint(x)
309 #define ieee754sp_fix(x) ieee754sp_tint(x)
310
311 #endif /* __ARCH_MIPS_MATH_EMU_IEEE754_H */
312