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
|
%{
#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
#include <getopt.h>
size_t line_number = 1;
extern int yylex();
extern int yyparse();
extern FILE *yyin;
void yyerror(const char *s);
%}
%union {
int i_val;
float f_val;
char *s_val;
char *symbol;
}
%token <i_val> T_INTEGER
%token <f_val> T_FLOAT
%token <s_val> T_STRING
%token <symbol> T_LABEL
%token <symbol> T_INSTRUCTION
%token T_ENDL
%token T_COMMA
%token T_IMMEDIATE
%%
asm:
statements
;
statements:
statements statement
| statement
;
statement:
instruction_one_param_symbol T_ENDL
| instruction_one_param_immediate T_ENDL
| instruction_two_param_symbols T_ENDL
| instruction_symbol_immediate T_ENDL
| instruction_immediate_symbol T_ENDL
| T_ENDL
;
instruction_one_param_symbol:
T_INSTRUCTION T_LABEL {
printf("Found instruction %s(%s)\n", $1, $2);
};
instruction_one_param_immediate:
T_INSTRUCTION T_IMMEDIATE T_INTEGER {
printf("Found instruction %s(%d)\n", $1, $3);
};
instruction_two_param_symbols:
T_INSTRUCTION T_LABEL T_COMMA T_LABEL {
printf("Found instruction %s(%s, %s)\n", $1, $2, $4);
};
instruction_symbol_immediate:
T_INSTRUCTION T_LABEL T_COMMA T_IMMEDIATE T_INTEGER {
printf("Found instruction %s(%s, %d)\n", $1, $2, $5);
}
instruction_immediate_symbol:
T_INSTRUCTION T_IMMEDIATE T_INTEGER T_COMMA T_LABEL {
printf("Found instruction %s(%d, %s)\n", $1, $3, $5);
}
%%
void yyerror(const char *s) {
printf("Parser Error: %lu: %s\n", line_number, s);
}
int main(int argc, char *argv[]) {
FILE *input = stdin;
int j = 0;
while (j != -1) {
j = getopt(argc, argv, "o:");
switch (j) {
case 'o':
input = fopen(optarg, "r");
if (input == NULL) {
perror(argv[0]);
return -1;
}
break;
default:
break;
}
}
yyin = input;
yyparse();
}
|
