1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3    NetWinder Floating Point Emulator
4    (c) Rebel.COM, 1998,1999
5
6    Direct questions, comments to Scott Bambrough <scottb@netwinder.org>
7
8*/
9
10#include "fpa11.h"
11#include "softfloat.h"
12#include "fpopcode.h"
13
14union float64_components {
15	float64 f64;
16	unsigned int i[2];
17};
18
19float64 float64_exp(float64 Fm);
20float64 float64_ln(float64 Fm);
21float64 float64_sin(float64 rFm);
22float64 float64_cos(float64 rFm);
23float64 float64_arcsin(float64 rFm);
24float64 float64_arctan(float64 rFm);
25float64 float64_log(float64 rFm);
26float64 float64_tan(float64 rFm);
27float64 float64_arccos(float64 rFm);
28float64 float64_pow(float64 rFn, float64 rFm);
29float64 float64_pol(float64 rFn, float64 rFm);
30
31static float64 float64_rsf(struct roundingData *roundData, float64 rFn, float64 rFm)
32{
33	return float64_sub(roundData, rFm, rFn);
34}
35
36static float64 float64_rdv(struct roundingData *roundData, float64 rFn, float64 rFm)
37{
38	return float64_div(roundData, rFm, rFn);
39}
40
41static float64 (*const dyadic_double[16])(struct roundingData*, float64 rFn, float64 rFm) = {
42	[ADF_CODE >> 20] = float64_add,
43	[MUF_CODE >> 20] = float64_mul,
44	[SUF_CODE >> 20] = float64_sub,
45	[RSF_CODE >> 20] = float64_rsf,
46	[DVF_CODE >> 20] = float64_div,
47	[RDF_CODE >> 20] = float64_rdv,
48	[RMF_CODE >> 20] = float64_rem,
49
50	/* strictly, these opcodes should not be implemented */
51	[FML_CODE >> 20] = float64_mul,
52	[FDV_CODE >> 20] = float64_div,
53	[FRD_CODE >> 20] = float64_rdv,
54};
55
56static float64 float64_mvf(struct roundingData *roundData,float64 rFm)
57{
58	return rFm;
59}
60
61static float64 float64_mnf(struct roundingData *roundData,float64 rFm)
62{
63	union float64_components u;
64
65	u.f64 = rFm;
66#ifdef __ARMEB__
67	u.i[0] ^= 0x80000000;
68#else
69	u.i[1] ^= 0x80000000;
70#endif
71
72	return u.f64;
73}
74
75static float64 float64_abs(struct roundingData *roundData,float64 rFm)
76{
77	union float64_components u;
78
79	u.f64 = rFm;
80#ifdef __ARMEB__
81	u.i[0] &= 0x7fffffff;
82#else
83	u.i[1] &= 0x7fffffff;
84#endif
85
86	return u.f64;
87}
88
89static float64 (*const monadic_double[16])(struct roundingData *, float64 rFm) = {
90	[MVF_CODE >> 20] = float64_mvf,
91	[MNF_CODE >> 20] = float64_mnf,
92	[ABS_CODE >> 20] = float64_abs,
93	[RND_CODE >> 20] = float64_round_to_int,
94	[URD_CODE >> 20] = float64_round_to_int,
95	[SQT_CODE >> 20] = float64_sqrt,
96	[NRM_CODE >> 20] = float64_mvf,
97};
98
99unsigned int DoubleCPDO(struct roundingData *roundData, const unsigned int opcode, FPREG * rFd)
100{
101	FPA11 *fpa11 = GET_FPA11();
102	float64 rFm;
103	unsigned int Fm, opc_mask_shift;
104
105	Fm = getFm(opcode);
106	if (CONSTANT_FM(opcode)) {
107		rFm = getDoubleConstant(Fm);
108	} else {
109		switch (fpa11->fType[Fm]) {
110		case typeSingle:
111			rFm = float32_to_float64(fpa11->fpreg[Fm].fSingle);
112			break;
113
114		case typeDouble:
115			rFm = fpa11->fpreg[Fm].fDouble;
116			break;
117
118		default:
119			return 0;
120		}
121	}
122
123	opc_mask_shift = (opcode & MASK_ARITHMETIC_OPCODE) >> 20;
124	if (!MONADIC_INSTRUCTION(opcode)) {
125		unsigned int Fn = getFn(opcode);
126		float64 rFn;
127
128		switch (fpa11->fType[Fn]) {
129		case typeSingle:
130			rFn = float32_to_float64(fpa11->fpreg[Fn].fSingle);
131			break;
132
133		case typeDouble:
134			rFn = fpa11->fpreg[Fn].fDouble;
135			break;
136
137		default:
138			return 0;
139		}
140
141		if (dyadic_double[opc_mask_shift]) {
142			rFd->fDouble = dyadic_double[opc_mask_shift](roundData, rFn, rFm);
143		} else {
144			return 0;
145		}
146	} else {
147		if (monadic_double[opc_mask_shift]) {
148			rFd->fDouble = monadic_double[opc_mask_shift](roundData, rFm);
149		} else {
150			return 0;
151		}
152	}
153
154	return 1;
155}
156