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  • only in /asuswrt-rt-n18u-9.0.0.4.380.2695/release/src-rt-6.x.4708/linux/linux-2.6.36/arch/arm/nwfpe/
1/*
2    NetWinder Floating Point Emulator
3    (c) Rebel.COM, 1998,1999
4
5    Direct questions, comments to Scott Bambrough <scottb@netwinder.org>
6
7    This program is free software; you can redistribute it and/or modify
8    it under the terms of the GNU General Public License as published by
9    the Free Software Foundation; either version 2 of the License, or
10    (at your option) any later version.
11
12    This program is distributed in the hope that it will be useful,
13    but WITHOUT ANY WARRANTY; without even the implied warranty of
14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15    GNU General Public License for more details.
16
17    You should have received a copy of the GNU General Public License
18    along with this program; if not, write to the Free Software
19    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
20*/
21
22#include "fpa11.h"
23#include "softfloat.h"
24#include "fpopcode.h"
25
26union float64_components {
27	float64 f64;
28	unsigned int i[2];
29};
30
31float64 float64_exp(float64 Fm);
32float64 float64_ln(float64 Fm);
33float64 float64_sin(float64 rFm);
34float64 float64_cos(float64 rFm);
35float64 float64_arcsin(float64 rFm);
36float64 float64_arctan(float64 rFm);
37float64 float64_log(float64 rFm);
38float64 float64_tan(float64 rFm);
39float64 float64_arccos(float64 rFm);
40float64 float64_pow(float64 rFn, float64 rFm);
41float64 float64_pol(float64 rFn, float64 rFm);
42
43static float64 float64_rsf(struct roundingData *roundData, float64 rFn, float64 rFm)
44{
45	return float64_sub(roundData, rFm, rFn);
46}
47
48static float64 float64_rdv(struct roundingData *roundData, float64 rFn, float64 rFm)
49{
50	return float64_div(roundData, rFm, rFn);
51}
52
53static float64 (*const dyadic_double[16])(struct roundingData*, float64 rFn, float64 rFm) = {
54	[ADF_CODE >> 20] = float64_add,
55	[MUF_CODE >> 20] = float64_mul,
56	[SUF_CODE >> 20] = float64_sub,
57	[RSF_CODE >> 20] = float64_rsf,
58	[DVF_CODE >> 20] = float64_div,
59	[RDF_CODE >> 20] = float64_rdv,
60	[RMF_CODE >> 20] = float64_rem,
61
62	/* strictly, these opcodes should not be implemented */
63	[FML_CODE >> 20] = float64_mul,
64	[FDV_CODE >> 20] = float64_div,
65	[FRD_CODE >> 20] = float64_rdv,
66};
67
68static float64 float64_mvf(struct roundingData *roundData,float64 rFm)
69{
70	return rFm;
71}
72
73static float64 float64_mnf(struct roundingData *roundData,float64 rFm)
74{
75	union float64_components u;
76
77	u.f64 = rFm;
78#ifdef __ARMEB__
79	u.i[0] ^= 0x80000000;
80#else
81	u.i[1] ^= 0x80000000;
82#endif
83
84	return u.f64;
85}
86
87static float64 float64_abs(struct roundingData *roundData,float64 rFm)
88{
89	union float64_components u;
90
91	u.f64 = rFm;
92#ifdef __ARMEB__
93	u.i[0] &= 0x7fffffff;
94#else
95	u.i[1] &= 0x7fffffff;
96#endif
97
98	return u.f64;
99}
100
101static float64 (*const monadic_double[16])(struct roundingData *, float64 rFm) = {
102	[MVF_CODE >> 20] = float64_mvf,
103	[MNF_CODE >> 20] = float64_mnf,
104	[ABS_CODE >> 20] = float64_abs,
105	[RND_CODE >> 20] = float64_round_to_int,
106	[URD_CODE >> 20] = float64_round_to_int,
107	[SQT_CODE >> 20] = float64_sqrt,
108	[NRM_CODE >> 20] = float64_mvf,
109};
110
111unsigned int DoubleCPDO(struct roundingData *roundData, const unsigned int opcode, FPREG * rFd)
112{
113	FPA11 *fpa11 = GET_FPA11();
114	float64 rFm;
115	unsigned int Fm, opc_mask_shift;
116
117	Fm = getFm(opcode);
118	if (CONSTANT_FM(opcode)) {
119		rFm = getDoubleConstant(Fm);
120	} else {
121		switch (fpa11->fType[Fm]) {
122		case typeSingle:
123			rFm = float32_to_float64(fpa11->fpreg[Fm].fSingle);
124			break;
125
126		case typeDouble:
127			rFm = fpa11->fpreg[Fm].fDouble;
128			break;
129
130		default:
131			return 0;
132		}
133	}
134
135	opc_mask_shift = (opcode & MASK_ARITHMETIC_OPCODE) >> 20;
136	if (!MONADIC_INSTRUCTION(opcode)) {
137		unsigned int Fn = getFn(opcode);
138		float64 rFn;
139
140		switch (fpa11->fType[Fn]) {
141		case typeSingle:
142			rFn = float32_to_float64(fpa11->fpreg[Fn].fSingle);
143			break;
144
145		case typeDouble:
146			rFn = fpa11->fpreg[Fn].fDouble;
147			break;
148
149		default:
150			return 0;
151		}
152
153		if (dyadic_double[opc_mask_shift]) {
154			rFd->fDouble = dyadic_double[opc_mask_shift](roundData, rFn, rFm);
155		} else {
156			return 0;
157		}
158	} else {
159		if (monadic_double[opc_mask_shift]) {
160			rFd->fDouble = monadic_double[opc_mask_shift](roundData, rFm);
161		} else {
162			return 0;
163		}
164	}
165
166	return 1;
167}
168