blob: 61c86f692b652476ef2529daf823132df7fc9449 (
plain)
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
|
CALL_ASM = """@{return_address}
D=A
@SP
A=M
M=D
@LCL
D=M
@SP
AM=M+1
M=D
@ARG
D=M
@SP
AM=M+1
M=D
@THIS
D=M
@SP
AM=M+1
M=D
@THAT
D=M
@SP
AM=M+1
M=D
@SP
MD=M+1
@LCL
M=D
@{arg_lcl_offset}
D=D-A
@ARG
M=D
@{function_label}
0;JMP
({return_address})
"""
FUNCTION_ASM = "({function_label})\n"
# repeated (n-1) times for function with n arguments
INIT_ONE_VAR_ASM = """@SP
AM=M+1
M=0
"""
# concatenated only when function has arguments
INIT_VARS_ASM = """@SP
A=M
M=0
{init_vars}@SP
M=M+1
"""
RETURN_ASM = """@LCL
D=M
@5
A=D-A
D=M
@{tmp}
M=D
@SP
A=M-1
D=M
@ARG
A=M
M=D
@ARG
D=M+1
@SP
M=D
@LCL
AM=M-1
D=M
@THAT
M=D
@LCL
AM=M-1
D=M
@THIS
M=D
@LCL
AM=M-1
D=M
@ARG
M=D
@LCL
AM=M-1
D=M
@LCL
M=D
@{tmp}
A=M
0;JMP
"""
ret_idx = {}
def translate_function(action, function, n, prog, verbose=False):
global ret_idx
try:
n = int(n)
except ValueError:
exit_on_error(f"Syntax error: not an integer: {n}", EXIT_CODE_SYNTAX_ERROR)
asm = f"// {action} {function} {n}\n" if verbose else ""
if action == "call":
if prog not in ret_idx:
ret_idx[prog] = 0
else:
ret_idx[prog] += 1
asm += CALL_ASM.format(
return_address=f"{prog}$ret.{ret_idx[prog]}",
arg_lcl_offset=(5 + n),
function_label=f"{function}",
)
else:
asm += FUNCTION_ASM.format(function_label=f"{function}")
if n > 0:
# function has arguments
asm += INIT_VARS_ASM.format(init_vars=INIT_ONE_VAR_ASM * (n - 1))
return asm
def translate_return(verbose=False):
asm = "// return\n" if verbose else ""
asm += RETURN_ASM.format(tmp="R13")
return asm
|
