xref: /OK3568_Linux_fs/kernel/arch/mips/math-emu/ieee754dp.h (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun /* SPDX-License-Identifier: GPL-2.0-only */
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun  * IEEE754 floating point
4*4882a593Smuzhiyun  * double precision internal header file
5*4882a593Smuzhiyun  */
6*4882a593Smuzhiyun /*
7*4882a593Smuzhiyun  * MIPS floating point support
8*4882a593Smuzhiyun  * Copyright (C) 1994-2000 Algorithmics Ltd.
9*4882a593Smuzhiyun  */
10*4882a593Smuzhiyun 
11*4882a593Smuzhiyun #include <linux/compiler.h>
12*4882a593Smuzhiyun 
13*4882a593Smuzhiyun #include "ieee754int.h"
14*4882a593Smuzhiyun 
15*4882a593Smuzhiyun #define assert(expr) ((void)0)
16*4882a593Smuzhiyun 
17*4882a593Smuzhiyun #define DP_EBIAS	1023
18*4882a593Smuzhiyun #define DP_EMIN		(-1022)
19*4882a593Smuzhiyun #define DP_EMAX		1023
20*4882a593Smuzhiyun #define DP_FBITS	52
21*4882a593Smuzhiyun #define DP_MBITS	52
22*4882a593Smuzhiyun 
23*4882a593Smuzhiyun #define DP_MBIT(x)	((u64)1 << (x))
24*4882a593Smuzhiyun #define DP_HIDDEN_BIT	DP_MBIT(DP_FBITS)
25*4882a593Smuzhiyun #define DP_SIGN_BIT	DP_MBIT(63)
26*4882a593Smuzhiyun 
27*4882a593Smuzhiyun #define DPSIGN(dp)	(dp.sign)
28*4882a593Smuzhiyun #define DPBEXP(dp)	(dp.bexp)
29*4882a593Smuzhiyun #define DPMANT(dp)	(dp.mant)
30*4882a593Smuzhiyun 
ieee754dp_finite(union ieee754dp x)31*4882a593Smuzhiyun static inline int ieee754dp_finite(union ieee754dp x)
32*4882a593Smuzhiyun {
33*4882a593Smuzhiyun 	return DPBEXP(x) != DP_EMAX + 1 + DP_EBIAS;
34*4882a593Smuzhiyun }
35*4882a593Smuzhiyun 
36*4882a593Smuzhiyun /* 3bit extended double precision sticky right shift */
37*4882a593Smuzhiyun #define XDPSRS(v,rs)	\
38*4882a593Smuzhiyun 	((rs > (DP_FBITS+3))?1:((v) >> (rs)) | ((v) << (64-(rs)) != 0))
39*4882a593Smuzhiyun 
40*4882a593Smuzhiyun #define XDPSRSX1() \
41*4882a593Smuzhiyun 	(xe++, (xm = (xm >> 1) | (xm & 1)))
42*4882a593Smuzhiyun 
43*4882a593Smuzhiyun #define XDPSRS1(v)	\
44*4882a593Smuzhiyun 	(((v) >> 1) | ((v) & 1))
45*4882a593Smuzhiyun 
46*4882a593Smuzhiyun /* 32bit * 32bit => 64bit unsigned integer multiplication */
47*4882a593Smuzhiyun #define DPXMULT(x, y)	((u64)(x) * (u64)y)
48*4882a593Smuzhiyun 
49*4882a593Smuzhiyun /* convert denormal to normalized with extended exponent */
50*4882a593Smuzhiyun #define DPDNORMx(m,e) \
51*4882a593Smuzhiyun 	while ((m >> DP_FBITS) == 0) { m <<= 1; e--; }
52*4882a593Smuzhiyun #define DPDNORMX	DPDNORMx(xm, xe)
53*4882a593Smuzhiyun #define DPDNORMY	DPDNORMx(ym, ye)
54*4882a593Smuzhiyun #define DPDNORMZ	DPDNORMx(zm, ze)
55*4882a593Smuzhiyun 
builddp(int s,int bx,u64 m)56*4882a593Smuzhiyun static inline union ieee754dp builddp(int s, int bx, u64 m)
57*4882a593Smuzhiyun {
58*4882a593Smuzhiyun 	union ieee754dp r;
59*4882a593Smuzhiyun 
60*4882a593Smuzhiyun 	assert((s) == 0 || (s) == 1);
61*4882a593Smuzhiyun 	assert((bx) >= DP_EMIN - 1 + DP_EBIAS
62*4882a593Smuzhiyun 	       && (bx) <= DP_EMAX + 1 + DP_EBIAS);
63*4882a593Smuzhiyun 	assert(((m) >> DP_FBITS) == 0);
64*4882a593Smuzhiyun 
65*4882a593Smuzhiyun 	r.sign = s;
66*4882a593Smuzhiyun 	r.bexp = bx;
67*4882a593Smuzhiyun 	r.mant = m;
68*4882a593Smuzhiyun 
69*4882a593Smuzhiyun 	return r;
70*4882a593Smuzhiyun }
71*4882a593Smuzhiyun 
72*4882a593Smuzhiyun extern union ieee754dp __cold ieee754dp_nanxcpt(union ieee754dp);
73*4882a593Smuzhiyun extern union ieee754dp ieee754dp_format(int, int, u64);
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