PageRenderTime 37ms CodeModel.GetById 18ms app.highlight 15ms RepoModel.GetById 1ms app.codeStats 0ms

/arch/mips/math-emu/ieee754.h

http://github.com/mirrors/linux
C Header | 311 lines | 219 code | 43 blank | 49 comment | 2 complexity | 90c58130301471a728a9beec1a1a61e4 MD5 | raw file
  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
 22union 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
 32union 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*/
 45int ieee754sp_class(union ieee754sp x);
 46
 47union ieee754sp ieee754sp_abs(union ieee754sp x);
 48union ieee754sp ieee754sp_neg(union ieee754sp x);
 49
 50union ieee754sp ieee754sp_add(union ieee754sp x, union ieee754sp y);
 51union ieee754sp ieee754sp_sub(union ieee754sp x, union ieee754sp y);
 52union ieee754sp ieee754sp_mul(union ieee754sp x, union ieee754sp y);
 53union ieee754sp ieee754sp_div(union ieee754sp x, union ieee754sp y);
 54
 55union ieee754sp ieee754sp_fint(int x);
 56union ieee754sp ieee754sp_flong(s64 x);
 57union ieee754sp ieee754sp_fdp(union ieee754dp x);
 58union ieee754sp ieee754sp_rint(union ieee754sp x);
 59
 60int ieee754sp_tint(union ieee754sp x);
 61s64 ieee754sp_tlong(union ieee754sp x);
 62
 63int ieee754sp_cmp(union ieee754sp x, union ieee754sp y, int cop, int sig);
 64
 65union ieee754sp ieee754sp_sqrt(union ieee754sp x);
 66
 67union ieee754sp ieee754sp_maddf(union ieee754sp z, union ieee754sp x,
 68				union ieee754sp y);
 69union ieee754sp ieee754sp_msubf(union ieee754sp z, union ieee754sp x,
 70				union ieee754sp y);
 71union ieee754sp ieee754sp_madd(union ieee754sp z, union ieee754sp x,
 72				union ieee754sp y);
 73union ieee754sp ieee754sp_msub(union ieee754sp z, union ieee754sp x,
 74				union ieee754sp y);
 75union ieee754sp ieee754sp_nmadd(union ieee754sp z, union ieee754sp x,
 76				union ieee754sp y);
 77union ieee754sp ieee754sp_nmsub(union ieee754sp z, union ieee754sp x,
 78				union ieee754sp y);
 79int ieee754sp_2008class(union ieee754sp x);
 80union ieee754sp ieee754sp_fmin(union ieee754sp x, union ieee754sp y);
 81union ieee754sp ieee754sp_fmina(union ieee754sp x, union ieee754sp y);
 82union ieee754sp ieee754sp_fmax(union ieee754sp x, union ieee754sp y);
 83union ieee754sp ieee754sp_fmaxa(union ieee754sp x, union ieee754sp y);
 84
 85/*
 86 * double precision (often aka double)
 87*/
 88int ieee754dp_class(union ieee754dp x);
 89
 90union ieee754dp ieee754dp_add(union ieee754dp x, union ieee754dp y);
 91union ieee754dp ieee754dp_sub(union ieee754dp x, union ieee754dp y);
 92union ieee754dp ieee754dp_mul(union ieee754dp x, union ieee754dp y);
 93union ieee754dp ieee754dp_div(union ieee754dp x, union ieee754dp y);
 94
 95union ieee754dp ieee754dp_abs(union ieee754dp x);
 96union ieee754dp ieee754dp_neg(union ieee754dp x);
 97
 98union ieee754dp ieee754dp_fint(int x);
 99union ieee754dp ieee754dp_flong(s64 x);
100union ieee754dp ieee754dp_fsp(union ieee754sp x);
101union ieee754dp ieee754dp_rint(union ieee754dp x);
102
103int ieee754dp_tint(union ieee754dp x);
104s64 ieee754dp_tlong(union ieee754dp x);
105
106int ieee754dp_cmp(union ieee754dp x, union ieee754dp y, int cop, int sig);
107
108union ieee754dp ieee754dp_sqrt(union ieee754dp x);
109
110union ieee754dp ieee754dp_maddf(union ieee754dp z, union ieee754dp x,
111				union ieee754dp y);
112union ieee754dp ieee754dp_msubf(union ieee754dp z, union ieee754dp x,
113				union ieee754dp y);
114union ieee754dp ieee754dp_madd(union ieee754dp z, union ieee754dp x,
115				union ieee754dp y);
116union ieee754dp ieee754dp_msub(union ieee754dp z, union ieee754dp x,
117				union ieee754dp y);
118union ieee754dp ieee754dp_nmadd(union ieee754dp z, union ieee754dp x,
119				union ieee754dp y);
120union ieee754dp ieee754dp_nmsub(union ieee754dp z, union ieee754dp x,
121				union ieee754dp y);
122int ieee754dp_2008class(union ieee754dp x);
123union ieee754dp ieee754dp_fmin(union ieee754dp x, union ieee754dp y);
124union ieee754dp ieee754dp_fmina(union ieee754dp x, union ieee754dp y);
125union ieee754dp ieee754dp_fmax(union ieee754dp x, union ieee754dp y);
126union ieee754dp ieee754dp_fmaxa(union ieee754dp x, union ieee754dp y);
127
128
129/* 5 types of floating point number
130*/
131enum {
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 */
157struct _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 *)(&current->thread.fpu.fcr31))
171
172static inline unsigned int ieee754_getrm(void)
173{
174	return (ieee754_csr.rm);
175}
176
177static inline unsigned int ieee754_setrm(unsigned int rm)
178{
179	return (ieee754_csr.rm = rm);
180}
181
182/*
183 * get current exceptions
184 */
185static inline unsigned int ieee754_getcx(void)
186{
187	return (ieee754_csr.cx);
188}
189
190/* test for current exception condition
191 */
192static inline int ieee754_cxtest(unsigned int n)
193{
194	return (ieee754_csr.cx & n);
195}
196
197/*
198 * get sticky exceptions
199 */
200static inline unsigned int ieee754_getsx(void)
201{
202	return (ieee754_csr.sx);
203}
204
205/* clear sticky conditions
206*/
207static inline unsigned int ieee754_clrsx(void)
208{
209	return (ieee754_csr.sx = 0);
210}
211
212/* test for sticky exception condition
213 */
214static inline int ieee754_sxtest(unsigned int n)
215{
216	return (ieee754_csr.sx & n);
217}
218
219/* debugging */
220union ieee754sp ieee754sp_dump(char *s, union ieee754sp x);
221union 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
242extern const union ieee754dp __ieee754dp_spcvals[];
243extern 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 */
277static inline int ieee754si_indef(void)
278{
279	return ieee754_csr.nan2008 ? 0 : INT_MAX;
280}
281
282static inline s64 ieee754di_indef(void)
283{
284	return ieee754_csr.nan2008 ? 0 : S64_MAX;
285}
286
287/*
288 * Overflow integer value
289 */
290static inline int ieee754si_overflow(int xs)
291{
292	return ieee754_csr.nan2008 && xs ? INT_MIN : INT_MAX;
293}
294
295static 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 */