Statistics
| Branch: | Revision:

root / target-arm / nwfpe / fpopcode.c @ 5fafdf24

History | View | Annotate | Download (4.1 kB)

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
#include "fpsr.h"
26
//#include "fpmodule.h"
27
//#include "fpmodule.inl"
28

    
29
const floatx80 floatx80Constant[] = {
30
  { 0x0000000000000000ULL, 0x0000},        /* extended 0.0 */
31
  { 0x8000000000000000ULL, 0x3fff},        /* extended 1.0 */
32
  { 0x8000000000000000ULL, 0x4000},        /* extended 2.0 */
33
  { 0xc000000000000000ULL, 0x4000},        /* extended 3.0 */
34
  { 0x8000000000000000ULL, 0x4001},        /* extended 4.0 */
35
  { 0xa000000000000000ULL, 0x4001},        /* extended 5.0 */
36
  { 0x8000000000000000ULL, 0x3ffe},        /* extended 0.5 */
37
  { 0xa000000000000000ULL, 0x4002}        /* extended 10.0 */
38
}; 
39

    
40
const float64 float64Constant[] = {
41
  0x0000000000000000ULL,                /* double 0.0 */
42
  0x3ff0000000000000ULL,                /* double 1.0 */
43
  0x4000000000000000ULL,                /* double 2.0 */
44
  0x4008000000000000ULL,                /* double 3.0 */
45
  0x4010000000000000ULL,                /* double 4.0 */
46
  0x4014000000000000ULL,                /* double 5.0 */
47
  0x3fe0000000000000ULL,                /* double 0.5 */
48
  0x4024000000000000ULL                        /* double 10.0 */
49
}; 
50

    
51
const float32 float32Constant[] = {
52
  0x00000000,                                /* single 0.0 */
53
  0x3f800000,                                /* single 1.0 */
54
  0x40000000,                                /* single 2.0 */
55
  0x40400000,                                /* single 3.0 */
56
  0x40800000,                                /* single 4.0 */
57
  0x40a00000,                                /* single 5.0 */
58
  0x3f000000,                                /* single 0.5 */
59
  0x41200000                                /* single 10.0 */
60
}; 
61

    
62
unsigned int getTransferLength(const unsigned int opcode)
63
{
64
  unsigned int nRc;
65
 
66
  switch (opcode & MASK_TRANSFER_LENGTH)
67
  {
68
    case 0x00000000: nRc = 1; break; /* single precision */
69
    case 0x00008000: nRc = 2; break; /* double precision */
70
    case 0x00400000: nRc = 3; break; /* extended precision */
71
    default: nRc = 0;
72
  }
73
 
74
  return(nRc);
75
}
76

    
77
unsigned int getRegisterCount(const unsigned int opcode)
78
{
79
  unsigned int nRc;
80
 
81
  switch (opcode & MASK_REGISTER_COUNT)
82
  {
83
    case 0x00000000: nRc = 4; break;
84
    case 0x00008000: nRc = 1; break;
85
    case 0x00400000: nRc = 2; break;
86
    case 0x00408000: nRc = 3; break;
87
    default: nRc = 0;
88
  }
89
 
90
  return(nRc);
91
}
92

    
93
unsigned int getRoundingPrecision(const unsigned int opcode)
94
{
95
  unsigned int nRc;
96
 
97
  switch (opcode & MASK_ROUNDING_PRECISION)
98
  {
99
    case 0x00000000: nRc = 1; break;
100
    case 0x00000080: nRc = 2; break;
101
    case 0x00080000: nRc = 3; break;
102
    default: nRc = 0;
103
  }
104
 
105
  return(nRc);
106
}
107

    
108
unsigned int getDestinationSize(const unsigned int opcode)
109
{
110
  unsigned int nRc;
111
 
112
  switch (opcode & MASK_DESTINATION_SIZE)
113
  {
114
    case 0x00000000: nRc = typeSingle; break;
115
    case 0x00000080: nRc = typeDouble; break;
116
    case 0x00080000: nRc = typeExtended; break;
117
    default: nRc = typeNone;
118
  }
119
 
120
  return(nRc);
121
}
122

    
123
/* condition code lookup table
124
 index into the table is test code: EQ, NE, ... LT, GT, AL, NV
125
 bit position in short is condition code: NZCV */
126
static const unsigned short aCC[16] = {
127
    0xF0F0, // EQ == Z set
128
    0x0F0F, // NE
129
    0xCCCC, // CS == C set
130
    0x3333, // CC
131
    0xFF00, // MI == N set
132
    0x00FF, // PL
133
    0xAAAA, // VS == V set
134
    0x5555, // VC
135
    0x0C0C, // HI == C set && Z clear
136
    0xF3F3, // LS == C clear || Z set
137
    0xAA55, // GE == (N==V)
138
    0x55AA, // LT == (N!=V)
139
    0x0A05, // GT == (!Z && (N==V))
140
    0xF5FA, // LE == (Z || (N!=V))
141
    0xFFFF, // AL always
142
    0 // NV
143
};
144

    
145
unsigned int checkCondition(const unsigned int opcode, const unsigned int ccodes)
146
{
147
  return (aCC[opcode>>28] >> (ccodes>>28)) & 1;
148
}