1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
|
/*
Copyright 2021-2023 Gabriel Jensen.
This file is part of Luma.
Luma is free software: you can redistribute it
and/or modify it under the terms of the GNU
Affero General Public License as published by
the Free Software Foundation, either version 3
of the License, or (at your option) any later
version.
Luma is distributed in the hope that it will be
useful, but WITHOUT ANY WARRANTY; without even
the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Affero General Public License for more details.
You should have received a copy of the GNU
Affero General Public License along with Luma.
If not, see <https://www.gnu.org/licenses/>.
*/
use crate::shifter::Shifter;
use crate::state::State;
impl State {
#[must_use]
pub fn shifter_value(&self, shifter: Shifter) -> (u32, bool) {
use Shifter::*;
let c = self.read_cpsr() & 0b00100000000000000000000000000000 != 0x0;
let (value, carry) = match shifter {
Immediate(imm, rot) => {
let result = (imm as u32).rotate_right(rot as u32);
let c = if rot == 0x0 { c } else { result & 0b10000000000000000000000000000000 != 0x0 };
(result, c)
},
ArithmeticShiftRightImmediate(rm, imm) => {
let rm_value = self.read_register(rm);
let result = (rm_value as i32).wrapping_shr(imm as u32) as u32;
let c = false; // TODO
(result, c)
},
ArithmeticShiftRightRegister(rm, rs) => {
let rm_value = self.read_register(rm);
let rs_value = self.read_register(rs);
let result = (rm_value as i32).wrapping_shr(rs_value) as u32;
let c = false; // TODO
(result, c)
},
LogicalShiftLeftImmediate(rm, imm) => {
let rm_value = self.read_register(rm);
let result = rm_value.wrapping_shl(imm as u32);
let c = false; // TODO
(result, c)
},
LogicalShiftLeftRegister(rm, rs) => {
let rm_value = self.read_register(rm);
let rs_value = self.read_register(rs);
let result = rm_value.wrapping_shl(rs_value);
let c = false; // TODO
(result, c)
},
LogicalShiftRightImmediate(rm, imm) => {
let rm_value = self.read_register(rm);
let result = rm_value.wrapping_shr(imm as u32);
let c = false; // TODO
(result, c)
},
LogicalShiftRightRegister(rm, rs) => {
let rm_value = self.read_register(rm);
let rs_value = self.read_register(rs);
let result = rm_value.wrapping_shr(rs_value);
let c = false; // TODO
(result, c)
},
RotateRightImmediate(rm, imm) => {
let rm_value = self.read_register(rm);
let result = rm_value.rotate_right(imm as u32);
let c = false; // TODO
(result, c)
},
RotateRightRegister(rm, rs) => {
let rm_value = self.read_register(rm);
let rs_value = self.read_register(rs);
let result = rm_value.rotate_right(rs_value);
let c = false; // TODO
(result, c)
},
RotateRightExtend(rm) => {
let rm_value = self.read_register(rm);
let result = 0x0_u32; // TODO
let c = rm_value & 0b00000000000000000000000000000001 != 0x0;
(result, c)
},
};
return (value, carry);
}
}
|
