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
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
|
// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
using System;
using System.Diagnostics;
namespace ILCompiler.DependencyAnalysis.ARM
{
public struct ARMEmitter
{
public ARMEmitter(NodeFactory factory, bool relocsOnly)
{
Builder = new ObjectDataBuilder(factory, relocsOnly);
TargetRegister = new TargetRegisterMap(factory.Target.OperatingSystem);
}
public ObjectDataBuilder Builder;
public TargetRegisterMap TargetRegister;
// check the value length
private static bool IsBitNumOverflow(int value, byte numBits)
{
return (value >> numBits) != 0;
}
private static bool IsLowReg(Register reg)
{
return !IsBitNumOverflow((int)reg, 3);
}
private static bool IsValidReg(Register reg)
{
return !IsBitNumOverflow((int)reg, 4);
}
// mov reg, immediate
// reg range: [0..7]
// immediage range: [0..255]
public void EmitMOV(Register reg, int immediate)
{
Debug.Assert(IsLowReg(reg) && !IsBitNumOverflow(immediate, 8));
Builder.EmitShort((short)(0x2000 + ((byte)reg << 8) + immediate));
}
// cmp reg, immediate
// reg range: [0..7]
// immediage range: [0..255]
public void EmitCMP(Register reg, int immediate)
{
Debug.Assert(IsLowReg(reg) && !IsBitNumOverflow(immediate, 8));
Builder.EmitShort((short)(0x2800 + ((byte)reg << 8) + immediate));
}
// add reg, immediate
// reg range: [0..7]
// immediage range: [0..255]
public void EmitADD(Register reg, int immediate)
{
Debug.Assert(IsLowReg(reg) && !IsBitNumOverflow(immediate, 8));
Builder.EmitShort((short)(0x3000 + ((byte)reg << 8) + immediate));
}
// sub reg, immediate
// reg range: [0..7]
// immediage range: [0..255]
public void EmitSUB(Register reg, int immediate)
{
Debug.Assert(IsLowReg(reg) && !IsBitNumOverflow(immediate, 8));
Builder.EmitShort((short)(0x3800 + ((byte)reg << 8) + immediate));
}
// nop
public void EmitNOP()
{
Builder.EmitByte(0x00);
Builder.EmitByte(0xbf);
}
// __debugbreak
public void EmitDebugBreak()
{
Builder.EmitByte(0xde);
Builder.EmitByte(0xfe);
}
// push reg
// reg range: [0..12, LR]
public void EmitPUSH(Register reg)
{
Debug.Assert(reg >= Register.R0 && (reg <= Register.R12 || reg == TargetRegister.LR));
Builder.EmitByte(0x4d);
Builder.EmitByte(0xf8);
Builder.EmitShort((short)(0x0d04 + ((byte)reg << 12)));
}
// pop reg
// reg range: [0..12, LR, PC]
public void EmitPOP(Register reg)
{
Debug.Assert(IsValidReg(reg) && reg != TargetRegister.SP);
Builder.EmitByte(0x5d);
Builder.EmitByte(0xf8);
Builder.EmitShort((short)(0x0b04 + ((byte)reg << 12)));
}
// mov reg, reg
// reg range: [0..PC]
public void EmitMOV(Register destination, Register source)
{
Debug.Assert(IsValidReg(destination) && IsValidReg(source));
Builder.EmitShort((short)(0x4600 + (((byte)destination & 0x8) << 4) + (((byte)source & 0x8) << 3) + (((byte)source & 0x7) << 3) + ((byte)destination & 0x7)));
}
// ldr reg, [reg]
// reg range: [0..7]
public void EmitLDR(Register destination, Register source)
{
Debug.Assert(IsLowReg(destination) && IsLowReg(source));
Builder.EmitShort((short)(0x6800 + (((byte)source & 0x7) << 3) + ((byte)destination & 0x7)));
}
// ldr.w reg, [reg, #offset]
// reg range: [0..PC]
// offset range: [-255..4095]
public void EmitLDR(Register destination, Register source, int offset)
{
Debug.Assert(IsValidReg(destination) && IsValidReg(source));
Debug.Assert(offset >= -255 && offset <= 4095);
if (offset >= 0)
{
Builder.EmitShort((short)(0xf8d0 + ((byte)(source))));
Builder.EmitShort((short)(offset + (((byte)destination) << 12)));
}
else
{
Builder.EmitShort((short)(0xf850 + ((byte)(source))));
Builder.EmitShort((short)(-offset + (((byte)destination) << 12) + (((byte)12) << 8)));
}
}
// movw reg, [reloc] & 0x0000FFFF
// movt reg, [reloc] & 0xFFFF0000
// reg range: [0..12, LR]
public void EmitMOV(Register destination, ISymbolNode symbol)
{
Debug.Assert(destination >= Register.R0 && (destination <= Register.R12 || destination == TargetRegister.LR));
Builder.EmitReloc(symbol, RelocType.IMAGE_REL_BASED_THUMB_MOV32);
Builder.EmitShort(unchecked((short)0xf240));
Builder.EmitShort((short)((byte)destination << 8));
Builder.EmitShort(unchecked((short)0xf2c0));
Builder.EmitShort((short)((byte)destination << 8));
}
// b.w symbol
public void EmitJMP(ISymbolNode symbol)
{
Debug.Assert(!symbol.RepresentsIndirectionCell);
Builder.EmitReloc(symbol, RelocType.IMAGE_REL_BASED_THUMB_BRANCH24);
Builder.EmitByte(0);
Builder.EmitByte(0xF0);
Builder.EmitByte(0);
Builder.EmitByte(0xB8);
}
// bx reg
// reg range: [0..PC]
public void EmitJMP(Register destination)
{
Debug.Assert(IsValidReg(destination));
Builder.EmitShort((short)(0x4700 + ((byte)destination << 3)));
}
// bx lr
public void EmitRET()
{
EmitJMP(TargetRegister.LR);
}
// bne #offset
// offset range: [-256..254]
public void EmitBNE(int immediate)
{
Debug.Assert(immediate >= -256 && immediate <= 254);
// considering the pipeline with PC
immediate -= 4;
Builder.EmitByte((byte)(immediate >> 1));
Builder.EmitByte(0xD1);
}
// beq #offset
// offset range: [-256..254]
public void EmitBEQ(int immediate)
{
Debug.Assert(immediate >= -256 && immediate <= 254);
// considering the pipeline with PC
immediate -= 4;
Builder.EmitByte((byte)(immediate >> 1));
Builder.EmitByte(0xD0);
}
// bne label(+4): ret(2) + next(2)
// bx lr
// label: ...
public void EmitRETIfEqual()
{
EmitBNE(4);
EmitRET();
}
}
}
|
