1/* SPDX-License-Identifier: GPL-2.0-only */
2/*
3 * IEEE754 floating point
4 * double precision internal header file
5 */
6/*
7 * MIPS floating point support
8 * Copyright (C) 1994-2000 Algorithmics Ltd.
9 */
10
11#include <linux/compiler.h>
12
13#include "ieee754int.h"
14
15#define assert(expr) ((void)0)
16
17#define DP_EBIAS 1023
18#define DP_EMIN (-1022)
19#define DP_EMAX 1023
20#define DP_FBITS 52
21#define DP_MBITS 52
22
23#define DP_MBIT(x) ((u64)1 << (x))
24#define DP_HIDDEN_BIT DP_MBIT(DP_FBITS)
25#define DP_SIGN_BIT DP_MBIT(63)
26
27#define DPSIGN(dp) (dp.sign)
28#define DPBEXP(dp) (dp.bexp)
29#define DPMANT(dp) (dp.mant)
30
31static inline int ieee754dp_finite(union ieee754dp x)
32{
33 return DPBEXP(x) != DP_EMAX + 1 + DP_EBIAS;
34}
35
36/* 3bit extended double precision sticky right shift */
37#define XDPSRS(v,rs) \
38 ((rs > (DP_FBITS+3))?1:((v) >> (rs)) | ((v) << (64-(rs)) != 0))
39
40#define XDPSRSX1() \
41 (xe++, (xm = (xm >> 1) | (xm & 1)))
42
43#define XDPSRS1(v) \
44 (((v) >> 1) | ((v) & 1))
45
46/* 32bit * 32bit => 64bit unsigned integer multiplication */
47#define DPXMULT(x, y) ((u64)(x) * (u64)y)
48
49/* convert denormal to normalized with extended exponent */
50#define DPDNORMx(m,e) \
51 while ((m >> DP_FBITS) == 0) { m <<= 1; e--; }
52#define DPDNORMX DPDNORMx(xm, xe)
53#define DPDNORMY DPDNORMx(ym, ye)
54#define DPDNORMZ DPDNORMx(zm, ze)
55
56static inline union ieee754dp builddp(int s, int bx, u64 m)
57{
58 union ieee754dp r;
59
60 assert((s) == 0 || (s) == 1);
61 assert((bx) >= DP_EMIN - 1 + DP_EBIAS
62 && (bx) <= DP_EMAX + 1 + DP_EBIAS);
63 assert(((m) >> DP_FBITS) == 0);
64
65 r.sign = s;
66 r.bexp = bx;
67 r.mant = m;
68
69 return r;
70}
71
72extern union ieee754dp __cold ieee754dp_nanxcpt(union ieee754dp);
73extern union ieee754dp ieee754dp_format(int, int, u64);
74

source code of linux/arch/mips/math-emu/ieee754dp.h