-
Notifications
You must be signed in to change notification settings - Fork 2
/
objectcode.py
180 lines (164 loc) · 6.48 KB
/
objectcode.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
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
import re
regs = [
't1', 't2', 't3', 't4', 't5', 't6', 't7', 't8', 't9', 's0', 's1', 's2',
's3', 's4', 's5', 's6', 's7'
]
table = {}
reg_ok = {}
variables = []
def Load_Var(Inter):
global variables
temp_re = '(temp\d+)'
for line in Inter:
temps = re.findall(temp_re, ' '.join(line))
variables += temps
def Load_Inter(filename):
lines = []
for line in open(filename, 'r', encoding='utf-8'):
line = line.replace('\r', '').replace('\n', '')
if line == '':
continue
lines.append(line.split(' '))
return lines
def Get_R(string):
try:
variables.remove(string)
except:
pass
if string in table:
return '$' + table[string] #如果已经存在寄存器分配，那么直接返回寄存器
else:
keys = []
for key in table: #已经分配寄存器的变量key
keys.append(key)
for key in keys: #当遇到未分配寄存器的变量时，清空之前所有分配的临时变量的映射关系！！！
if 'temp' in key and key not in variables: #
reg_ok[table[key]] = 1
del table[key]
for reg in regs: #对于所有寄存器
if reg_ok[reg] == 1: #如果寄存器可用
table[string] = reg #将可用寄存器分配给该变量，映射关系存到table中
reg_ok[reg] = 0 #寄存器reg设置为已用
return '$' + reg
def translate(line):
if line[0] == 'LABEL':
return line[1] + ':'
if line[1] == ':=':
if len(line) == 3:
if line[-1][0] == '#':
return '\tli %s,%s' % (Get_R(line[0]), line[-1].replace(
'#', ''))
else:
return '\tmove %s,%s' % (Get_R(line[0]), Get_R(line[2]))
if len(line) == 5:
if line[3] == '+':
if line[-1][0] == '#':
return '\taddi %s,%s,%s' % (Get_R(line[0]), Get_R(line[2]),
line[-1].replace('#', ''))
else:
return '\tadd %s,%s,%s' % (Get_R(line[0]), Get_R(line[2]),
Get_R(line[-1]))
elif line[3] == '-':
if line[-1][0] == '#':
return '\taddi %s,%s,-%s' % (Get_R(line[0]), Get_R(
line[2]), line[-1].replace('#', ''))
else:
return '\tsub %s,%s,%s' % (Get_R(line[0]), Get_R(line[2]),
Get_R(line[-1]))
elif line[3] == '*':
return '\tmul %s,%s,%s' % (Get_R(line[0]), Get_R(line[2]),
Get_R(line[-1]))
elif line[3] == '/':
return '\tdiv %s,%s\n\tmflo %s' % (Get_R(
line[2]), Get_R(line[-1]), Get_R(line[0]))
elif line[3] == '<':
return '\tslt %s,%s,%s' % (Get_R(line[0]), Get_R(line[2]),
Get_R(line[-1]))
elif line[3] == '>':
return '\tslt %s,%s,%s' % (Get_R(line[0]), Get_R(line[-1]),
Get_R(line[2]))
if line[2] == 'CALL':
if line[3] == 'read' or line[3] == 'print':
return '\taddi $sp,$sp,-4\n\tsw $ra,0($sp)\n\tjal %s\n\tlw $ra,0($sp)\n\tmove %s,$v0\n\taddi $sp,$sp,4' % (
line[-1], Get_R(line[0]))
else:
return '\taddi $sp,$sp,-24\n\tsw $t0,0($sp)\n\tsw $ra,4($sp)\n\tsw $t1,8($sp)\n\tsw $t2,12($sp)\n\tsw $t3,16($sp)\n\tsw $t4,20($sp)\n\tjal %s\n\tlw $a0,0($sp)\n\tlw $ra,4($sp)\n\tlw $t1,8($sp)\n\tlw $t2,12($sp)\n\tlw $t3,16($sp)\n\tlw $t4,20($sp)\n\taddi $sp,$sp,24\n\tmove %s $v0' % (
line[-1], Get_R(line[0]))
if line[0] == 'GOTO':
return '\tj %s' % line[1]
if line[0] == 'RETURN':
return '\tmove $v0,%s\n\tjr $ra' % Get_R(line[1])
if line[0] == 'IF':
if line[2] == '==':
return '\tbeq %s,%s,%s' % (Get_R(line[1]), Get_R(line[3]),
line[-1])
if line[2] == '!=':
return '\tbne %s,%s,%s' % (Get_R(line[1]), Get_R(line[3]),
line[-1])
if line[2] == '>':
return '\tbgt %s,%s,%s' % (Get_R(line[1]), Get_R(line[3]),
line[-1])
if line[2] == '<':
return '\tblt %s,%s,%s' % (Get_R(line[1]), Get_R(line[3]),
line[-1])
if line[2] == '>=':
return '\tbge %s,%s,%s' % (Get_R(line[1]), Get_R(line[3]),
line[-1])
if line[2] == '<=':
return '\tble %s,%s,%s' % (Get_R(line[1]), Get_R(line[3]),
line[-1])
if line[0] == 'FUNCTION':
return '%s:' % line[1]
if line[0] == 'CALL':
if line[-1] == 'read' or line[-1] == 'print':
return '\taddi $sp,$sp,-4\n\tsw $ra,0($sp)\n\tjal %s\n\tlw $ra,0($sp)\n\taddi $sp,$sp,4' % (
line[-1])
else:
return '\taddi $sp,$sp,-24\n\tsw $t0,0($sp)\n\tsw $ra,4($sp)\n\tsw $t1,8($sp)\n\tsw $t2,12($sp)\n\tsw $t3,16($sp)\n\tsw $t4,20($sp)\n\tjal %s\n\tlw $a0,0($sp)\n\tlw $ra,4($sp)\n\tlw $t1,8($sp)\n\tlw $t2,12($sp)\n\tlw $t3,16($sp)\n\tlw $t4,20($sp)\n\taddi $sp,$sp,24\n\tmove %s $v0' % (
line[-1], Get_R(line[0]))
if line[0] == 'ARG':
return '\tmove $t0,$a0\n\tmove $a0,%s' % Get_R(line[-1])
if line[0] == 'PARAM':
table[line[-1]] = 'a0'
return ''
def write_to_txt(Obj):
f = open('result.asm', 'w')
template = '''
.data
_prompt: .asciiz "Enter an integer:"
_ret: .asciiz "\\n"
.globl main
.text
read:
li $v0,4
la $a0,_prompt
syscall
li $v0,5
syscall
jr $ra
print:
li $v0,1
syscall
li $v0,4
la $a0,_ret
syscall
move $v0,$0
jr $ra
'''
f.write(template)
for line in Obj:
f.write(line + '\n')
f.close()
def parser():
for reg in regs:
reg_ok[reg] = 1 # 初始化，所有寄存器都可用
Inter = Load_Inter('./innerCode.txt') # 读取中间代码
Load_Var(Inter) # 第一遍扫描，记录所有变量
Obj = []
for line in Inter:
obj_line = translate(line) # 翻译中间代码成MIPS汇编
if obj_line == '':
continue
Obj.append(obj_line)
write_to_txt(Obj)
parser()