-
Notifications
You must be signed in to change notification settings - Fork 262
/
instruction.py
126 lines (99 loc) · 2.77 KB
/
instruction.py
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
import dataclasses
from enum import Enum, auto
from typing import Optional
OFFSET_BITS = 16
N_FLAGS = 15
class Register(Enum):
AP = 0
FP = auto()
class BytecodeElement:
@property
def size(self):
raise NotImplementedError
@dataclasses.dataclass
class BytecodeData(BytecodeElement):
data: int
@property
def size(self):
return 1
@dataclasses.dataclass
class Instruction(BytecodeElement):
# Offsets. In the range [-2**15, 2*15) = [-2**(OFFSET_BITS-1), 2**(OFFSET_BITS-1)).
off0: int
off1: int
off2: int
# Immediate.
imm: Optional[int]
# Flags for operands.
dst_register: Register
op0_register: Register
class Op1Addr(Enum):
# op1 = [pc + 1].
IMM = 0
# op1 = [ap + off2].
AP = auto()
# op1 = [fp + off2].
FP = auto()
# op1 = [op0].
OP0 = auto()
op1_addr: Op1Addr
class Res(Enum):
# res = operand_1.
OP1 = 0
# res = operand_0 + operand_1.
ADD = auto()
# res = operand_0 * operand_1.
MUL = auto()
# res is not constrained.
UNCONSTRAINED = auto()
res: Res
# Flags for register update.
class PcUpdate(Enum):
# Next pc: pc + op_size.
REGULAR = 0
# Next pc: res (jmp abs).
JUMP = auto()
# Next pc: pc + res (jmp rel).
JUMP_REL = auto()
# Next pc: jnz_addr (jnz), where jnz_addr is a complex expression, representing the jnz
# logic.
JNZ = auto()
pc_update: PcUpdate
class ApUpdate(Enum):
# Next ap: ap.
REGULAR = 0
# Next ap: ap + [pc + 1].
ADD = auto()
# Next ap: ap + 1.
ADD1 = auto()
# Next ap: ap + 2.
ADD2 = auto()
ap_update: ApUpdate
class FpUpdate(Enum):
# Next fp: fp.
REGULAR = 0
# Next fp: ap + 2.
AP_PLUS2 = auto()
# Next fp: operand_dst.
DST = auto()
fp_update: FpUpdate
# Flags for opcodes.
class Opcode(Enum):
NOP = 0
ASSERT_EQ = auto()
CALL = auto()
RET = auto()
opcode: Opcode
@property
def size(self):
return 2 if self.imm is not None else 1
def decode_instruction_values(encoded_instruction):
"""
Returns a tuple (flags, off0, off1, off2) according to the given encoded instruction.
"""
assert 0 <= encoded_instruction < 2 ** (3 * OFFSET_BITS + N_FLAGS), "Unsupported instruction."
off0 = encoded_instruction & (2 ** OFFSET_BITS - 1)
off1 = (encoded_instruction >> OFFSET_BITS) & (2 ** OFFSET_BITS - 1)
off2 = (encoded_instruction >> (2 * OFFSET_BITS)) & (2 ** OFFSET_BITS - 1)
flags_val = encoded_instruction >> (3 * OFFSET_BITS)
return flags_val, off0, off1, off2