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 
14 floatx80 floatx80_exp(floatx80 Fm);
15 floatx80 floatx80_ln(floatx80 Fm);
16 floatx80 floatx80_sin(floatx80 rFm);
17 floatx80 floatx80_cos(floatx80 rFm);
18 floatx80 floatx80_arcsin(floatx80 rFm);
19 floatx80 floatx80_arctan(floatx80 rFm);
20 floatx80 floatx80_log(floatx80 rFm);
21 floatx80 floatx80_tan(floatx80 rFm);
22 floatx80 floatx80_arccos(floatx80 rFm);
23 floatx80 floatx80_pow(floatx80 rFn, floatx80 rFm);
24 floatx80 floatx80_pol(floatx80 rFn, floatx80 rFm);
25 
floatx80_rsf(struct roundingData * roundData,floatx80 rFn,floatx80 rFm)26 static floatx80 floatx80_rsf(struct roundingData *roundData, floatx80 rFn, floatx80 rFm)
27 {
28 	return floatx80_sub(roundData, rFm, rFn);
29 }
30 
floatx80_rdv(struct roundingData * roundData,floatx80 rFn,floatx80 rFm)31 static floatx80 floatx80_rdv(struct roundingData *roundData, floatx80 rFn, floatx80 rFm)
32 {
33 	return floatx80_div(roundData, rFm, rFn);
34 }
35 
36 static floatx80 (*const dyadic_extended[16])(struct roundingData*, floatx80 rFn, floatx80 rFm) = {
37 	[ADF_CODE >> 20] = floatx80_add,
38 	[MUF_CODE >> 20] = floatx80_mul,
39 	[SUF_CODE >> 20] = floatx80_sub,
40 	[RSF_CODE >> 20] = floatx80_rsf,
41 	[DVF_CODE >> 20] = floatx80_div,
42 	[RDF_CODE >> 20] = floatx80_rdv,
43 	[RMF_CODE >> 20] = floatx80_rem,
44 
45 	/* strictly, these opcodes should not be implemented */
46 	[FML_CODE >> 20] = floatx80_mul,
47 	[FDV_CODE >> 20] = floatx80_div,
48 	[FRD_CODE >> 20] = floatx80_rdv,
49 };
50 
floatx80_mvf(struct roundingData * roundData,floatx80 rFm)51 static floatx80 floatx80_mvf(struct roundingData *roundData, floatx80 rFm)
52 {
53 	return rFm;
54 }
55 
floatx80_mnf(struct roundingData * roundData,floatx80 rFm)56 static floatx80 floatx80_mnf(struct roundingData *roundData, floatx80 rFm)
57 {
58 	rFm.high ^= 0x8000;
59 	return rFm;
60 }
61 
floatx80_abs(struct roundingData * roundData,floatx80 rFm)62 static floatx80 floatx80_abs(struct roundingData *roundData, floatx80 rFm)
63 {
64 	rFm.high &= 0x7fff;
65 	return rFm;
66 }
67 
68 static floatx80 (*const monadic_extended[16])(struct roundingData*, floatx80 rFm) = {
69 	[MVF_CODE >> 20] = floatx80_mvf,
70 	[MNF_CODE >> 20] = floatx80_mnf,
71 	[ABS_CODE >> 20] = floatx80_abs,
72 	[RND_CODE >> 20] = floatx80_round_to_int,
73 	[URD_CODE >> 20] = floatx80_round_to_int,
74 	[SQT_CODE >> 20] = floatx80_sqrt,
75 	[NRM_CODE >> 20] = floatx80_mvf,
76 };
77 
ExtendedCPDO(struct roundingData * roundData,const unsigned int opcode,FPREG * rFd)78 unsigned int ExtendedCPDO(struct roundingData *roundData, const unsigned int opcode, FPREG * rFd)
79 {
80 	FPA11 *fpa11 = GET_FPA11();
81 	floatx80 rFm;
82 	unsigned int Fm, opc_mask_shift;
83 
84 	Fm = getFm(opcode);
85 	if (CONSTANT_FM(opcode)) {
86 		rFm = getExtendedConstant(Fm);
87 	} else {
88 		switch (fpa11->fType[Fm]) {
89 		case typeSingle:
90 			rFm = float32_to_floatx80(fpa11->fpreg[Fm].fSingle);
91 			break;
92 
93 		case typeDouble:
94 			rFm = float64_to_floatx80(fpa11->fpreg[Fm].fDouble);
95 			break;
96 
97 		case typeExtended:
98 			rFm = fpa11->fpreg[Fm].fExtended;
99 			break;
100 
101 		default:
102 			return 0;
103 		}
104 	}
105 
106 	opc_mask_shift = (opcode & MASK_ARITHMETIC_OPCODE) >> 20;
107 	if (!MONADIC_INSTRUCTION(opcode)) {
108 		unsigned int Fn = getFn(opcode);
109 		floatx80 rFn;
110 
111 		switch (fpa11->fType[Fn]) {
112 		case typeSingle:
113 			rFn = float32_to_floatx80(fpa11->fpreg[Fn].fSingle);
114 			break;
115 
116 		case typeDouble:
117 			rFn = float64_to_floatx80(fpa11->fpreg[Fn].fDouble);
118 			break;
119 
120 		case typeExtended:
121 			rFn = fpa11->fpreg[Fn].fExtended;
122 			break;
123 
124 		default:
125 			return 0;
126 		}
127 
128 		if (dyadic_extended[opc_mask_shift]) {
129 			rFd->fExtended = dyadic_extended[opc_mask_shift](roundData, rFn, rFm);
130 		} else {
131 			return 0;
132 		}
133 	} else {
134 		if (monadic_extended[opc_mask_shift]) {
135 			rFd->fExtended = monadic_extended[opc_mask_shift](roundData, rFm);
136 		} else {
137 			return 0;
138 		}
139 	}
140 
141 	return 1;
142 }
143