1 /*
2 * IEEE754 floating point
3 * double precision internal header file
4 */
5 /*
6 * MIPS floating point support
7 * Copyright (C) 1994-2000 Algorithmics Ltd.
8 *
9 * This program is free software; you can distribute it and/or modify it
10 * under the terms of the GNU General Public License (Version 2) as
11 * published by the Free Software Foundation.
12 *
13 * This program is distributed in the hope it will be useful, but WITHOUT
14 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
15 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
16 * for more details.
17 *
18 * You should have received a copy of the GNU General Public License along
19 * with this program; if not, write to the Free Software Foundation, Inc.,
20 * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
21 */
22
23 #include <linux/compiler.h>
24
25 #include "ieee754int.h"
26
27 #define assert(expr) ((void)0)
28
29 #define SP_EBIAS 127
30 #define SP_EMIN (-126)
31 #define SP_EMAX 127
32 #define SP_FBITS 23
33 #define SP_MBITS 23
34
35 #define SP_MBIT(x) ((u32)1 << (x))
36 #define SP_HIDDEN_BIT SP_MBIT(SP_FBITS)
37 #define SP_SIGN_BIT SP_MBIT(31)
38
39 #define SPSIGN(sp) (sp.sign)
40 #define SPBEXP(sp) (sp.bexp)
41 #define SPMANT(sp) (sp.mant)
42
ieee754sp_finite(union ieee754sp x)43 static inline int ieee754sp_finite(union ieee754sp x)
44 {
45 return SPBEXP(x) != SP_EMAX + 1 + SP_EBIAS;
46 }
47
48 /* 64 bit right shift with rounding */
49 #define XSPSRS64(v, rs) \
50 (((rs) >= 64) ? ((v) != 0) : ((v) >> (rs)) | ((v) << (64-(rs)) != 0))
51
52 /* 3bit extended single precision sticky right shift */
53 #define XSPSRS(v, rs) \
54 ((rs > (SP_FBITS+3))?1:((v) >> (rs)) | ((v) << (32-(rs)) != 0))
55
56 #define XSPSRS1(m) \
57 ((m >> 1) | (m & 1))
58
59 #define SPXSRSX1() \
60 (xe++, (xm = XSPSRS1(xm)))
61
62 #define SPXSRSY1() \
63 (ye++, (ym = XSPSRS1(ym)))
64
65 /* convert denormal to normalized with extended exponent */
66 #define SPDNORMx(m,e) \
67 while ((m >> SP_FBITS) == 0) { m <<= 1; e--; }
68 #define SPDNORMX SPDNORMx(xm, xe)
69 #define SPDNORMY SPDNORMx(ym, ye)
70 #define SPDNORMZ SPDNORMx(zm, ze)
71
buildsp(int s,int bx,unsigned int m)72 static inline union ieee754sp buildsp(int s, int bx, unsigned int m)
73 {
74 union ieee754sp r;
75
76 assert((s) == 0 || (s) == 1);
77 assert((bx) >= SP_EMIN - 1 + SP_EBIAS
78 && (bx) <= SP_EMAX + 1 + SP_EBIAS);
79 assert(((m) >> SP_FBITS) == 0);
80
81 r.sign = s;
82 r.bexp = bx;
83 r.mant = m;
84
85 return r;
86 }
87
88 extern union ieee754sp __cold ieee754sp_nanxcpt(union ieee754sp);
89 extern union ieee754sp ieee754sp_format(int, int, unsigned);
90