xref: /qemu/linux-user/arm/nwfpe/fpopcode.c (revision 72ac97cd)
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, see <http://www.gnu.org/licenses/>.
19 */
20 
21 #include "fpa11.h"
22 #include "fpu/softfloat.h"
23 #include "fpopcode.h"
24 #include "fpsr.h"
25 //#include "fpmodule.h"
26 //#include "fpmodule.inl"
27 
28 const floatx80 floatx80Constant[] = {
29   { 0x0000000000000000ULL, 0x0000},	/* extended 0.0 */
30   { 0x8000000000000000ULL, 0x3fff},	/* extended 1.0 */
31   { 0x8000000000000000ULL, 0x4000},	/* extended 2.0 */
32   { 0xc000000000000000ULL, 0x4000},	/* extended 3.0 */
33   { 0x8000000000000000ULL, 0x4001},	/* extended 4.0 */
34   { 0xa000000000000000ULL, 0x4001},	/* extended 5.0 */
35   { 0x8000000000000000ULL, 0x3ffe},	/* extended 0.5 */
36   { 0xa000000000000000ULL, 0x4002}	/* extended 10.0 */
37 };
38 
39 const float64 float64Constant[] = {
40   const_float64(0x0000000000000000ULL),		/* double 0.0 */
41   const_float64(0x3ff0000000000000ULL),		/* double 1.0 */
42   const_float64(0x4000000000000000ULL),		/* double 2.0 */
43   const_float64(0x4008000000000000ULL),		/* double 3.0 */
44   const_float64(0x4010000000000000ULL),		/* double 4.0 */
45   const_float64(0x4014000000000000ULL),		/* double 5.0 */
46   const_float64(0x3fe0000000000000ULL),		/* double 0.5 */
47   const_float64(0x4024000000000000ULL)			/* double 10.0 */
48 };
49 
50 const float32 float32Constant[] = {
51   const_float32(0x00000000),				/* single 0.0 */
52   const_float32(0x3f800000),				/* single 1.0 */
53   const_float32(0x40000000),				/* single 2.0 */
54   const_float32(0x40400000),				/* single 3.0 */
55   const_float32(0x40800000),				/* single 4.0 */
56   const_float32(0x40a00000),				/* single 5.0 */
57   const_float32(0x3f000000),				/* single 0.5 */
58   const_float32(0x41200000)				/* single 10.0 */
59 };
60 
61 unsigned int getRegisterCount(const unsigned int opcode)
62 {
63   unsigned int nRc;
64 
65   switch (opcode & MASK_REGISTER_COUNT)
66   {
67     case 0x00000000: nRc = 4; break;
68     case 0x00008000: nRc = 1; break;
69     case 0x00400000: nRc = 2; break;
70     case 0x00408000: nRc = 3; break;
71     default: nRc = 0;
72   }
73 
74   return(nRc);
75 }
76 
77 unsigned int getDestinationSize(const unsigned int opcode)
78 {
79   unsigned int nRc;
80 
81   switch (opcode & MASK_DESTINATION_SIZE)
82   {
83     case 0x00000000: nRc = typeSingle; break;
84     case 0x00000080: nRc = typeDouble; break;
85     case 0x00080000: nRc = typeExtended; break;
86     default: nRc = typeNone;
87   }
88 
89   return(nRc);
90 }
91 
92 /* condition code lookup table
93  index into the table is test code: EQ, NE, ... LT, GT, AL, NV
94  bit position in short is condition code: NZCV */
95 static const unsigned short aCC[16] = {
96     0xF0F0, // EQ == Z set
97     0x0F0F, // NE
98     0xCCCC, // CS == C set
99     0x3333, // CC
100     0xFF00, // MI == N set
101     0x00FF, // PL
102     0xAAAA, // VS == V set
103     0x5555, // VC
104     0x0C0C, // HI == C set && Z clear
105     0xF3F3, // LS == C clear || Z set
106     0xAA55, // GE == (N==V)
107     0x55AA, // LT == (N!=V)
108     0x0A05, // GT == (!Z && (N==V))
109     0xF5FA, // LE == (Z || (N!=V))
110     0xFFFF, // AL always
111     0 // NV
112 };
113